+

WO2001001385A1 - Circuits a reseau de diodes electroluminescentes alimentes en courant alternatif pour afficheurs d'appareils de signalisation - Google Patents

Circuits a reseau de diodes electroluminescentes alimentes en courant alternatif pour afficheurs d'appareils de signalisation Download PDF

Info

Publication number
WO2001001385A1
WO2001001385A1 PCT/US1999/014876 US9914876W WO0101385A1 WO 2001001385 A1 WO2001001385 A1 WO 2001001385A1 US 9914876 W US9914876 W US 9914876W WO 0101385 A1 WO0101385 A1 WO 0101385A1
Authority
WO
WIPO (PCT)
Prior art keywords
coupled
leds
circuit according
series connected
voltage source
Prior art date
Application number
PCT/US1999/014876
Other languages
English (en)
Inventor
Welles Reymond
Original Assignee
Welles Reymond
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Welles Reymond filed Critical Welles Reymond
Priority to AU48500/99A priority Critical patent/AU4850099A/en
Priority to PCT/US1999/014876 priority patent/WO2001001385A1/fr
Publication of WO2001001385A1 publication Critical patent/WO2001001385A1/fr

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08G—TRAFFIC CONTROL SYSTEMS
    • G08G1/00—Traffic control systems for road vehicles
    • G08G1/09—Arrangements for giving variable traffic instructions
    • G08G1/095—Traffic lights
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/35—Balancing circuits
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/37—Converter circuits
    • H05B45/3725—Switched mode power supply [SMPS]
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/395—Linear regulators
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/31—Phase-control circuits
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/37—Converter circuits
    • H05B45/3725—Switched mode power supply [SMPS]
    • H05B45/38—Switched mode power supply [SMPS] using boost topology
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Definitions

  • the invention relates to light emitting diode arrays. More particularly, the invention relates to circuits incorporating light emitting diode arrays which are powered by an alternating current and which are advantageously used in traffic signal and other displays.
  • Modern traffic signal systems include two major components: the controller and the display (lights).
  • the technology of modern traffic signal controllers is quite evolved and includes modern computer technology which incorporates traffic flow sensors, timers, and the like.
  • traffic signal displays have not changed significantly.
  • the displays utilize high power broad spectrum incandescent bulbs with colored filters to produce the desired traffic signal color.
  • traffic signal displays are inefficient, as they consume large amounts of energy in order to produce a display which is bright enough to be seen in broad daylight.
  • the inefficiency of the displays is due in part to the general inefficiency of incandescent bulbs, and is exacerbated by the fact that much of the light energy produced by the bulbs is wasted by filtering the light.
  • traffic signal displays require frequent maintenance.
  • Incandescent bulbs have a relatively short life span, typically less than eight thousand hours, shorter still if switched on and off frequently and if constantly exposed to the elements; all of which are the case with traffic signals.
  • LED light emitting diode
  • Such arrays are disclosed, for example, in U.S. Patent Number 4,271,408 to Teshima et al., U.S. Patent Number 4,298,869 to Okuno, and U.S. Patent Number 4,954,822 to Borenstein, the complete disclosures of which are hereby incorporated herein by reference.
  • An LED array can provide many advantages when used in lieu of an incandescent bulb. The primary advantages are that an LED array is much more efficient than an incandescent bulb and requires little or no maintenance.
  • an LED array will consume about one tenth the power that a filtered incandescent bulb will consume to produce the same light output.
  • the life cycle costs of a traffic signal using an LED array in lieu of an incandescent bulb is also significantly reduced since incandescent bulbs used in traffic signals typically must be replaced once or twice a year.
  • a well designed LED array could be expected to function for more than twenty years before requiring replacement.
  • Another, less apparent advantage is that a single array can be used to display many different illuminated symbols such as international symbols for turn only, do not enter, walk, don't walk, etc.
  • the LED array is more resistant to the elements and is more mechanically durable than an incandescent bulb. It is also possible to achieve a higher flashing rate with an LED array than with an incandescent bulb.
  • an LED array does not require a light reflector like the relatively large parabolical reflectors used with incandescent bulbs.
  • the elimination of the reflector is an advantage because during certain seasons at certain times of day, sunlight can be reflected off the reflector in an incandescent bulb traffic signal and cause a confusing display.
  • Yet another advantage of an LED array is that, if it is properly arranged, when faults develop in the array, the entire array need not fail.
  • LED arrays are not easily retro-fitted to an existing traffic signal. This is primarily because existing incandescent displays operate with a "standard" 120 volt 60 Hz AC power supply. LEDs require a DC current of approximately 5 to 20 milliamps and a forward operating voltage of between 1.5 to 2.5 volts depending on the wavelength of the emitted light and the semiconductor material used. Another reason why retro-fitting is difficult is because the "standard" traffic signal housings are designed to accept a "standard” incandescent bulb. These issues have been addressed in the art.
  • Okuno avoids the use of a rectifier bridge by providing an array of LEDs 24 which are connected in series and polarized in one direction and an array of LEDs 26 which are connected in series and polarized in the opposite direction.
  • the two arrays 24 and 26 are connected in parallel so that a respective array is illuminated during each half cycle of the AC power supply.
  • a current limiting resistor 28 (a generator resistor) must be connected in series with the arrays. Assuming each array 24 and 26 includes twenty-five LEDs, the value of the resistor 28 should be approximately 3300 ohms to produce the desired average LED current.
  • the resistor Since approximately 70% of the line voltage is dropped across the resistor 28, the resistor is the dominant factor in determining the LED current and energy is wasted by the resistor. In this example, the arrangement has an efficiency of only about 35% and the LED current has a range of ⁇ 25%. If a greater number of LEDs were used, the efficiency would increase, but the current range would widen.
  • LED arrays used in traffic displays and to make recommendations about these characteristics. See. e.g.. Interim LED Purchase Specifications of the Institute of Transportation Engineers. Part 2, July 1998.
  • One of the characteristics of LED arrays is the power factor (a value between zero and 1) and it has been recommended that the power factor be greater than 0.9.
  • Another characteristic is total harmonic distortion (THD-F) which is recommended to be less than 20%.
  • TDD-F total harmonic distortion
  • the ratio of peak to average current is indicative of the number of lumens obtained per watt of power. A low peak to average current is more efficient. Current regulation is also important in LED arrays as the line voltage (nominally 110-120 in the U.S.) normally fluctuates.
  • LED arrays might interfere with other traffic control devices.
  • emergency vehicles are equipped with a light transmitter which modulates light in a manner similar to a IN remote control.
  • Traffic signals are equipped with a light receiver so that the traffic signal can be controlled by an approaching emergency vehicle.
  • AC powered LED arrays of the type shown in prior art Figure 3 self full wave rectifying
  • this modulation will interfere with emergency vehicle remote traffic signal control.
  • the LED array circuit of the present invention includes a number of series connected LED pairs, each pair including two parallel connected oppositely polarized LEDs, which are coupled to a standard AC voltage source by an inductor which is arranged in series between the AC voltage source and the LED array.
  • the inductor is preferably provided with a Q>5 and a reactance which is equivalent to the resistance of a current generator or current limiting resistor.
  • the use of an inductor in place of a resistor increases the efficiency of the array circuit to approximately 80% if the inductor is properly chosen.
  • the efficiency of the array circuit is increased even further by coupling a capacitor in parallel to the array, thereby generating an impedance converter which converts an AC voltage source into a high impedance AC current source.
  • the efficiency of the array is greater than 80%.
  • the capacitor is included in the circuit, the power factor of the circuit is improved, non-linearity of the circuit is diluted, the impedance of the source is increased, and the LED array may include a large number of LEDs (e.g., forty pairs or more). In fact, so many LEDs may be included in the array such that the voltage drop across the array is greater than the AC line peak voltage itself.
  • the LED array and circuit are mounted on a circuit board which is connected by spacers to a clear circular disk.
  • the disk is dimensioned to take the place of a standard traffic signal filter/lens.
  • This embodiment is retrofitted to an existing traffic signal by removing the bulb, reflector, and filter/lens from the traffic signal and mounting the clear circular disk in place of the filter.
  • a single retro-fittable unit is provided wherein an inductor, a capacitor, and an array of LEDs are contained in a housing having substantially the same size and shape as a standard incandescent bulb used in a traffic signal display.
  • a plurality of individually switched arrays are contained in a single module where a first terminal of each array is coupled to a common point which is series connected through a single inductor to the AC voltage source, and a separate capacitor is coupled parallel to each array.
  • the second terminal of each array is coupled through a respective individual switch to the AC voltage source.
  • the second embodiment provides a module for several independently operable mutually exclusive displays.
  • circuits which have improved power factors include circuits which have improved power factors, LED arrays which tolerate the failure of individual arrays regardless of whether the failure is a short or open, circuits which compensate for the effects of temperature on LED luminance, circuits which regulate the current through the LED array as line voltage varies, circuits which balance the peak to average current ratio through the LED arrays, circuits which minimize harmonic distortion, and circuits which minimize the possibility of interference with emergency remote control of traffic signals.
  • circuits are provided for switching the current applied to LED arrays according to a plurality of parameters such as ambient temperature, ambient light, voltage, etc.
  • Figure 1 is a schematic diagram of a prior art LED array circuit using a transformed and rectified power supply with LEDs coupled in parallel;
  • Figure 2 is a schematic diagram of a prior art LED array circuit using a filtered and rectified power supply with LEDs coupled in series with a current limiting resistor
  • Figure 3 is a schematic diagram of a prior art LED array circuit with oppositely polarized series connected LEDs coupled in series with a current limiting resistor;
  • Figure 4 is a schematic diagram of a first embodiment of an LED array circuit according to the invention.
  • Figure 5 is a schematic diagram of a second embodiment of an LED array circuit according to the invention.
  • Figure 6 is a partially transparent side elevation view of a housing for the LED array circuit of Figure 5 which is adapted for retro-fitting in an existing traffic signal display;
  • Figure 7 is a cross sectional schematic view of a prior art traffic signal display having an incandescent bulb, a reflector, and a colored filter/lens;
  • Figure 8 is a side elevation schematic view of an LED array according to the invention mounted on a circular disk for retro-fitting in an existing traffic signal display;
  • Figure 9 is a cross sectional view similar to Figure 7 showing the LED array of Figure 8 installed in an existing traffic signal display;
  • Figure 10 is a schematic diagram of a third embodiment of an LED array circuit according to the invention.
  • Figure 11 is a schematic diagram of an LED array circuit similar to Figure 4 but having a higher power factor than other embodiments;
  • Figure 12 is a schematic diagram of a portion of an LED array which is protected against the failure of individual LEDs
  • Figure 13 is a schematic diagram of a series circuit for temperature compensation
  • Figure 14 is a schematic diagram of a series circuit for current regulation
  • Figure 15 is a schematic diagram of an enhanced series circuit for current regulation and balancing
  • Figure 16 is a schematic diagram of a circuit for temperature compensation, current regulation, and balancing
  • Figure 17 is a schematic diagram of an LED array circuit similar to Figure 5 but having a higher power factor
  • Figure 18 is a schematic diagram similar to Figure 5 but with temperature compensation
  • Figure 19 is a schematic diagram similar to Figure 5 but which provides higher current and lower voltage for parallel LED arrays
  • Figure 20 is a schematic diagram of a series LED array with a full wave rectifier and filter capacitor for use with the L-C circuit power supply according to the invention
  • Figure 21 is a schematic diagram similar to Figure 20 but showing groups of LEDs protected against the failure of individual LEDs;
  • Figure 22 is a schematic diagram similar to Figure 21 but with a circuit for temperature compensation and current regulation;
  • Figure 23 is a schematic diagram of a circuit including several series LED arrays coupled to each other in parallel, each having a current sharing impedance;
  • Figure 24 is a schematic diagram of a current sharing impedance for use in the circuit of Figure 23;
  • Figure 25 is a schematic diagram of a current sharing impedance for use in the circuit of Figure 23;
  • Figure 26 is a schematic diagram of dual series LED arrays having an electronic balancing circuit
  • Figure 27 is a schematic diagram similar to Figure 26 but with a circuit for temperature compensation and current regulation;
  • Figure 28 is a schematic diagram similar to Figure 5 but with the locations of the inductor and capacitor interchanged;
  • Figure 29 is a schematic diagram similar to Figure 28 but with a tapped inductor;
  • Figure 30 is a schematic diagram of a circuit for switching a pair of LED arrays to provide a brighter or dimmer output;
  • Figure 31 is a schematic diagram of a circuit for automatically switching the circuit of Figure 30;
  • Figure 32 is a schematic diagram of a lossless resonant synchronous boost regulator circuit
  • Figure 33 is a schematic diagram of an LED array circuit and a separate switching circuit for controlling the light output of the array according to a plurality of parameters.
  • a first embodiment of an LED array circuit 30 includes an array of LEDs 31 arranged as a plurality of LED pairs 32, and an inductor L.
  • the LED pairs 32 each include two parallel coupled LEDs 32a, 32b which are oppositely polarized.
  • the LED pairs 32 are coupled to each other in series to form the LED array 31.
  • a first terminal or node 33 of the array is coupled to an AC voltage source 34 through the series connected inductor L, with the second terminal or node 35 of the array 31 coupled to the AC voltage source through a switch 36.
  • the switch 36 shown in Figure 4 is merely representative of some type of switching circuit and in practice will likely be part of a traffic signal controller.
  • connection of the circuit 30 to the AC voltage source 34 is preferably a removable connection as represented in Figure 4 by removable couplings 37 and 39.
  • the inductor L is chosen to have a reactance equivalent to the resistance of a current generator or current limiting resistor and to have Q>5.
  • the use of inductor L with the array 30 produces an efficiency of about 80% and achieves all of the advantages of LED arrays without suffering the disadvantages of the current limiting resistor of the prior art.
  • one of the LEDs in each pair will light and during the other half cycle, the other LED in each pair will hght.
  • One of the advantages of arranging the LEDs as shown is that if an LED faults either closed (short) or open, only that LED or one LED pair will be disabled. That is, if an LED shorts, all of the remaining LEDs will continue to function except for the one which is paired with the shorted LED and which will be shorted thereby. If, on the other hand, a red LED faults open, the LED which is paired with it will be forced to conduct reverse voltage during the half cycle in which the open faulted LED would have lit.
  • circuit of Figure 4 exhibits non-linear characteristics and that the most important factor in powering the LEDs is the average current which flows through the array of LEDs. If the voltage drop across the LED array is small relative to the peak line voltage, the current through the array is substantially related to the RMS short circuit current I s through the inductor L which is expressed below according to the approximation:
  • the impedance Z L of the inductor L is a complex number related to its inductance L by:
  • the average current through current T LED ( AVG ) through the array during each half cycle will be substantially equal to one half the average short circuit current Isc (AVG) through the inductor L so long as the voltage drop across the LED array is relatively small compared to the peak AC line voltage.
  • Isc average short circuit current
  • the efficiency, power factor, and control of current in the circuit of Figure 4 can be further enhanced by the addition of a capacitor C as shown in Figure 5.
  • the circuit 30a of Figure 5 is substantially the same as that in Figure 4, but with the addition of capacitor C which is coupled in parallel to the LED array 31 across the terminals 33 and 35.
  • the inductance of the inductor L is preferably chosen according to the relationship (4) given above.
  • the L-C circuit shown in Figure 5 is not a filter circuit but is an impedance converter which effectively converts the AC voltage source into a high impedance AC current source when the L- C circuit is tuned to the frequency of the AC source according to approximation:
  • the value of the capacitor C is preferably chosen according to the approximation:
  • the desired capacitance would be approximately l ⁇ F.
  • This arrangement effectively increases the current generator impedance Z g of the circuit by a factor of Q such that IZJ ⁇ QX L , with X L being the reactance of the inductor L. It also increases the open circuit voltage Vr j c by a factor of Q so that Vpc ⁇ QV.
  • the AC voltage source therefore appears to the LED array as a current source even when the voltage drop across the array is comparable to the peak AC line voltage. Because of the high current generator impedance, the same tuned circuit can tolerate a wide range in the number and types of LED pairs without materially affecting the LED current.
  • the tuned circuit can generate a voltage across the LED array which may be greater than the AC line voltage. Therefore, a very large number of LEDs can be used in the array. Indeed, in a preferred embodiment of the invention, forty or more pairs of LEDs are utilized. It should be noted that the inductor L, when used in the AC powered circuits described above, provides high impedance without energy wasting resistance.
  • FIG. 6 shows a popular existing traffic signal display 50 having a weather tight enclosure or casing 52 which contains an incandescent bulb 54 and a parabolic reflector 56. The inside of the enclosure 52 is accessible via a hinged door 58 which carries a colored lens/filter 60 (e.g.
  • the bulb 54 is held in a socket 64 which is electrically coupled to a voltage source (not shown) via a quick connect block 66.
  • the bulb 54, reflector 56, socket 64 and attached wires are also hinged to the enclosure 52.
  • the interior elements of the display 50 are all easily accessible and replaceable.
  • an LED array 31 is mounted on one side of a circuit board 70 which is provided with circuit traces and elements 72 on its other side.
  • the circuit elements and traces may include the inductor L, the capacitor C, and the connections of the array 31 as described with reference to Figures 4 and 5 above.
  • the circuit board 70 is coupled to a clear plastic disk 74 by a number of spacers 76 so that the LEDs 32 in the array 31 face the disk 74 as seen best in Figure 9.
  • both the disk 74 and the circuit board 70 are circular.
  • the disk 72 is fitted with a grommet 62 which is substantially the same as the grommet 62 used to hold the filter/lens 60 in the prior art display 50 described above.
  • the prior art display 50 of Figure 7 is modified by removing the lens/filter 60 with its grommet 62 and by removing the bulb 54, reflector 56, and socket 64.
  • the disk 74 with its grommet 62 is fitted into the opening in the hinged door 53 and the circuit 72 is electrically coupled to the quick connect block 66.
  • the portion of the circuit board 70 which faces the disk 74 should be painted black before mounting the LEDs 32. This prevents unwanted reflection off the circuit board during bright daylight hours.
  • the circuit 72 need not be mounted on the circuit board 70. All or part of the circuit 72 could be mounted off the board 70 inside the enclosure 52. As a practical matter, it may be advantageous to mount all of the circuit except for the inductor L on the circuit board 70 and mount the inductor L inside the enclosure 52
  • FIG. 10 shows a circuit 30b utilizing multiple LED arrays according to the invention.
  • LED arrays 31a, 31b, 31c each of which are substantially the same as the LED array 31 shown in Figure 5, are coupled by their first terminals 33a-33c to the AC voltage source 34 through a common inductor L and are coupled by their second terminals 35a-35c through individual respective switches 36a-36c to the AC voltage source.
  • Capacitors C a , C b , C c are respectively coupled in parallel to each array 31a, 31b, 31c across their respective terminals.
  • the circuit shown in Figure 10 assumes that each array is operated in mutual exclusivity so that the L-C circuit as described above operates in the same manner in this circuit when each array is turned on.
  • This type of circuit is well suited for a multiple display traffic signal.
  • the circuit is well suited for use in a red, yellow, and green traffic light where only one LED array is turned on at any given time.
  • a single inductor L can be shared by all of the LED arrays, thereby reducing the cost of the traffic signal display unit.
  • Figure 11 illustrates an improvement to the circuit of Figure 4 through the addition of an R-C network which increases the power factor.
  • the circuit 130 of Figure 11 is similar to the circuit 30 described above with similar reference numerals (increased by 100 referring to similar parts.
  • the series R-C network across nodes 137, 139 provides two benefits.
  • the value of C can be chosen so that the power factor is greater than 0.9.
  • C can be chosen to have a reactance similar to the reactance of the remainder of the circuit.
  • the value of R, chosen in conjunction with C can be chosen so that the R-C network protects the contacts of the switch 136 against arcing.
  • Figure 12 illustrates an LED module 232 containing four LED pairs 232-1, 232-2, 232- 3, 232-4 protected by a pair of Zener diodes Z a , Z b .
  • the Zener voltage (V z ) of each diodes Z a , Z j is nominally the same the other.
  • the sum of the Zener voltage (V z ) of either Zener and the forward threshold of either Zener (V d ) is chosen to be just greater than the peak voltage across the LED pairs.
  • Four LED pairs are shown for example. In practice, m number of LED pairs may be used.
  • the peak voltage drop (mV f ) across the group of m pairs of LEDs is less than V z +V d and the protective Zener pair Z A , Z B do not conduct and are not stressed. If an LED shorts, the protection Zeners are not called into play and the operation is as previously described, except for the loss of light from the pair which includes the shorted LED.
  • the function of the protective Zeners is to limit the voltage drop across the group in the "a" direction to slightly more than the normal mV f . This excess voltage is readily limited to about 2 volts. The limiting of the difference of voltage drops in opposite directions reduces the DC bias stress on the inductor so that continued operation in this failed mode is practical.
  • the module 232 is preferably utilized with additional identical modules coupled to each other in series and to an inductor or L-C power supply described above.
  • a series circuit is added in series between the LED modules and the power supply to improve the balance of current flowing in the "a" and "b" directions whether under normal or fault conditions.
  • Figures 13-15 illustrate examples of this type of series circuit.
  • Figure 13 illustrates a series circuit 241 consisting of a negative temperature coefficient resistor R ⁇ .
  • the proper choice of the value and temperature coefficient of this resistor can reduce the temperature effect on light output from more than 3 to 1 to less than 1.5 to 1.
  • the value of the resistor may be chosen empirically or with the aid of a graphing function.
  • Figure 14 shows a series circuit 341 which consists of an incandescent lamp "B".
  • the lamp preferably has a current rating which is at least four times the current which will flow through it.
  • Incandescent lamps increase their effective resistance rapidly as the operating current increases from zero to normal operating conditions. Resistance typically increases by a factor of 2.8 to 1 from 25% to 100% operating current.
  • the benefit of this circuit is improved current regulation with line voltage variations and improved current balance in the "a" and "b" directions under both normal and fault conditions.
  • Figure 15 shows a series circuit which consists of two incandescent lamps B a , B b and two steering diodes D a , D b .
  • bulb B a only responds to the current in the "a" LED direction and the B b lamp only responds to the current in the "b” LED direction.
  • this configuration improves the balance of current in the "a” and "b” directions.
  • the lamps should be operated well below their normal operational conditions.
  • Figure 16 illustrates an active electronic means for providing the functions of current regulation, current balancing, and temperature compensation at the same time.
  • the basic principle of operation is to sense the current through the LED array 232 and shunt excess current around the array. Shown are two separate shunt regulators, one that senses the current when the "a" LEDs are conducting and one that senses the current when the "b" LEDs are conducting.
  • the "a” shunt regulator includes resistor R SIa , Zener diode Z a , transistor Q a , current drawing resistor R a , and switching diodes D al , D ⁇ .
  • the "b” shunt regulator includes resistor R SIb , Zener diode Z b , transistor Q b , current drawing resistor R b , and switching diodes D bl ,
  • the values of the resistor R SIa is chosen so that when the current in the "a" LEDs exceeds the appropriate value, the voltage across R SIa exceeds the sum of the Zener voltage of Z a and the base emitter threshold voltage of Q a , which causes Q a to turn on thereby bypassing some of the input curcent around the anay through the current drawing resistor R a .
  • the value of the resistor R SIb is chosen in the same way with respect to the "b” LEDs.
  • the switching diodes D al , D ⁇ remove the "a” regulator from the circuit when the "b” regulator is functioning and the switching diodes D bl , D b2 remove the "b” regulator from the circuit when the "a” regulator is functioning.
  • temperature compensation will be accomplished.
  • R SIa increases in value as ambient temperature goes down
  • bypass current will start at a lower LED current as temperature decreases.
  • Figure 17 illustrates an improvement to the circuit of Figure 5 through the addition of an R-C network R and C j which is parallel to the L-C circuit and which increases the power factor.
  • the circuit 130a of Figure 17 is similar to the circuit 30a ( Figure 5) described above with similar reference numerals (increased by 100) referring to similar parts.
  • the series R-C network across nodes 137, 139 provides two benefits.
  • the value of C ] can be chosen so that the power factor is greater than 0.9.
  • the value of R, chosen in conjunction with C 1 can be chosen so that the R-C network protects the contacts of the switch 136 against arcing.
  • Figure 18 illustrates a circuit similar to the circuit 30a ( Figure 5) described above with similar reference numerals (increased by 200) refe ing to similar parts.
  • This circuit 230a differs from the circuit 30a by the inclusion of a negative temperature coefficient resistor RNTC in series between node 237 and the inductor L.
  • the resistor RNTC changes resistance in response to changes in temperature and thereby compensates for the sensitivity of LEDs to temperature.
  • Figure 19 illustrates a circuit similar to the circuit 30a ( Figure 5) described above with similar reference numerals (increased by 300) referring to similar parts.
  • This circuit 330a differs from the circuit 30a by the inclusion of a step-down autotransformer L P across the nodes 333, 335.
  • the inductance of transformer L P is preferably greater than or equal to four times the inductance of inductor L and the tap coefficient (k) is preferably less than 1.0.
  • This circuit provides, across nodes 333', 335', a lower voltage and a higher current than provided by the circuit 30a across nodes 33, 35. In particular, the circuit increases the short circuit current by a factor 1/k and decreases the open circuit voltage by the factor k.
  • FIG. 20 illustrates a circuit 331 which can replace the LED anay 31, 131, 231 described above.
  • the circuit 331 includes a series LED array 332, a full wave rectifier D D and a filtering capacitor C F .
  • the advantages of using this circuit in conjunction with the L or L-C power supply of the invention are several.
  • the peak to average cunent ratio approaches 1.0 and light modulation (flicker) is significantly reduced.
  • More complex series-parallel arrays can be used such as those described below with reference to Figures 23, 26, and 27.
  • DC current issues do not exist for the inductor. Since cunent is only flowing in one direction it is not necessary to balance the cunent flow in opposite direction.
  • Figure 21 illustrates a circuit similar to the circuit illustrated in Figure 20 but with improved failure performance.
  • the LED anay 432 includes "n" groups of “m” series connected LEDs. Each group of “m” LEDs has a parallel connected Zener diode Z a which conducts if one of the LEDs in the group should fail open.
  • Figure 22 illustrates a circuit similar to the circuit illustrated in Figure 21 but with a shunt regulator similar to those described above with reference to Figure 16.
  • the shunt regulator includes resistors R j , R SA , transistor Q j , and Zener diode Z b .
  • the shunt regulator provides cunent regulation and temperature compensation as described above.
  • FIG 23 illustrates a complex anay of "m" series anays coupled in parallel. As shown in Figure 23, each series anay 632-1 through 632-n is provided with a sharing impedance 641-1 through 641-n.
  • the sharing impedance is preferably comparable to the total dynamic impedance of the anay alone.
  • Figures 24 and 25 illustrate that the sharing impedance 641 may be either a resistor 641' or an incandescent lamp 641". The non-linear characteristics of the lamp produces better balance and more efficiency than the resistor.
  • Figure 26 illustrates a circuit 731 similar to the circuit 631 described above, but with an electronic cunent balancing circuit for balancing two series LED arrays 732-1 and 732-2 which are coupled parallel to each other.
  • the current balancing circuit includes seven resistors R R 6 , R Q and two transistors Q ls Q 2 which form a differential current steering circuit. In normal operation, the cunent through resistors R R Q , and R is equal. If an LED in the array 732-1 fails open, the voltage across resistor R j will drop lower than the voltage across the resistor R 2 . A higher dynamic impedance is created at the node of R 5 and the collector of Q 2 than the sum of Rj and R 5 . This causes the differential transistors Q Q 2 to steer more of the current through the resistor R Q to the anay 732-1 and less to the anay 732-2.
  • the circuit 731 provides excellent balance and efficiency.
  • Figure 27 illustrates a circuit 731a which is substantially the same as circuit 731 with the addition of a shunt regulator such as described above with reference to Figures 16 and 22.
  • the shunt regulator includes resistors R SA , R 7 , transistor Q 3 and Zener diode Z.
  • the circuit 73 la optionally includes a negative temperature compensation resistor R ⁇ Q .
  • Figure 28 illustrates a circuit 830 which is similar to the circuit 30a of Figure 5 but with the location of the inductor L and capacitor C interchanged.
  • Circuit 830 is not as prefened as embodiment as the circuit 30a has a better power factor and lower harmonic distortion.
  • one advantage of circuit 830 is that the exciting voltage of the inductor is limited to the LED array voltage which may allow the inductor to be smaller and cheaper.
  • Another advantage of interchanging the locations of the inductor and capacitor is illustrated in Figure 29.
  • Figure 29 illustrates a circuit 830a which is substantially the same as the circuit 830 but where the inductor L is provided with a tap to provide the function of a step down autotransformer as described above with reference to Figure 19 without the addition of an additional component.
  • Figure 30 illustrates a pair of LED anays 932-1, 932-2, each having an associated series circuit 941-1, 941-2, and a double pole double throw switch 951 controlled by unit 953.
  • the switch 951 changes the circuit anangement so that the LED anays may be ananged in series or in parallel (shown).
  • the average current through individual LEDs when the arrays are in series is approximately twice cunent through individual LEDs when the anays are in parallel.
  • the total light output of the two arrays is either doubled or halved by toggling the switch 951.
  • the switching unit 953 may be used to compensate for temperature or may be used to dim the LEDs at night.
  • Figure 31 shows a controller unit 953' which includes a relay 955 and a photocell 957 designed to dim the LEDs at night. It will be appreciated that the photocell 957 is provided with a filter (not shown) which filters out the wavelength of the LEDs.
  • Figure 32 shows a circuit 1030 which is similar to the circuit shown in Figure 21 having an inductor L, a capacitor C, a series LED anay 1032 with a full wave rectifier D j -D , and a filter capacitor C F .
  • the circuit 1030 also includes an LED array cunent sensor and controller 1059, a zero crossing detector 1061, and an opto relay 1063.
  • Those skilled in the art will appreciate that at the time the voltage across the capacitor C is crossing zero, the cunent stored in the inductor L is near its peak and is about to be passed into the load.
  • the circuit of Figure 32 causes the voltage across the capacitor to be momentarily held at zero after the zero crossing instant.
  • the LED cunent sensor and controller 1059 measures the difference between the desired average cunent and the actual average cunent. A voltage proportional to the difference is stored on a capacitor (not shown). At the time that the zero crossing is indicated by the detector 1061, the controller 1059 generates a pulse having a length proportional to the aforementioned stored voltage. (Below some threshold, no pulse is generated.) The pulse is used to activate the opto relay 1063 which shorts the capacitor C for the duration of the pulse. Since the relay shorts the capacitor when the energy in it is zero, this circuit is in principle lossless.
  • FIG 33 illustrates a system according to the invention having a separate LED circuit 1130 and traffic light controller circuit 1170.
  • the LED circuit 1130 may be any of the circuits previously described.
  • the controller circuit 1170 includes a triac 1172 which is controlled by a controller 1174 in response to inputs 1176, 1178, 1180.
  • the inputs 1176, 1178, 1180 may include a temperature sensor, a voltage sensor, a photocell, etc.
  • the triac and controller therefore, control the brightness of the LED anay as well as whether it is on or off.
  • a similar triac and controller could be located in the LED assembly 1130, rather than at the traffic controller location, to provide appropriate dimming of the LED anay while the traffic controller only controls whether the anay is on or off.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Circuit Arrangement For Electric Light Sources In General (AREA)

Abstract

L'invention concerne un circuit à réseau de diodes électroluminescentes (30b) comprenant un certain nombre de paires de diodes électroluminescentes (32) montées en série, chacune contenant deux diodes polarisées à l'opposé montées en parallèle. Le réseau est couplé à une alimentation en courant alternatif standard (34) montée en série avec un inducteur dont Q > 5 et une réactance qui équivaut à la résistance d'une résistance de limitation de courant. Le remplacement de la résistance par un inducteur augmente l'efficacité du circuit d'environ 80 %. L'efficacité est encore augmentée par le couplage d'un condensateur parallèle au circuit et par l'accord de l'inducteur et de la capacitance sur la fréquence de l'alimentation en courant alternatif (34). Selon un mode de réalisation, un seul module est équipé d'une pluralité de réseaux de diodes électroluminescentes (31a-31c), chaque réseau ayant son propre condensateur monté en parallèle et sa propre série montée sur un commutateur (36a, 36b ou 26c). Le module est couplé et circule à travers l'alimentation (34) à laquelle est couplé un noeud du module par un inducteur.
PCT/US1999/014876 1999-06-29 1999-06-29 Circuits a reseau de diodes electroluminescentes alimentes en courant alternatif pour afficheurs d'appareils de signalisation WO2001001385A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU48500/99A AU4850099A (en) 1999-06-29 1999-06-29 Ac powered led circuits for traffic signal displays
PCT/US1999/014876 WO2001001385A1 (fr) 1999-06-29 1999-06-29 Circuits a reseau de diodes electroluminescentes alimentes en courant alternatif pour afficheurs d'appareils de signalisation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US1999/014876 WO2001001385A1 (fr) 1999-06-29 1999-06-29 Circuits a reseau de diodes electroluminescentes alimentes en courant alternatif pour afficheurs d'appareils de signalisation

Publications (1)

Publication Number Publication Date
WO2001001385A1 true WO2001001385A1 (fr) 2001-01-04

Family

ID=22273099

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1999/014876 WO2001001385A1 (fr) 1999-06-29 1999-06-29 Circuits a reseau de diodes electroluminescentes alimentes en courant alternatif pour afficheurs d'appareils de signalisation

Country Status (2)

Country Link
AU (1) AU4850099A (fr)
WO (1) WO2001001385A1 (fr)

Cited By (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10140331A1 (de) * 2001-08-16 2003-04-03 Siemens Ag Lichtzeichen zur Verkehrssteuerung und Verfahren zur Funktionsüberwachung eines solchen Zeichens
WO2004003869A1 (fr) * 2002-06-27 2004-01-08 Jose Monzo Dispositif d'emission lumineuse, en particulier dispositif d'emission lumineuse pour feux de signalisation, constitue de diodes electroluminescentes
DE10235811A1 (de) * 2002-06-27 2004-01-29 Jose Monzo Lichtabgabeeinrichtung, insbesondere Verkehrssignal-Lichtabgabeeinrichtung, die mit Leuchtdioden aufgebaut ist
WO2005001791A1 (fr) * 2003-06-30 2005-01-06 Koninklijke Philips Electronics N.V. Circuit d'attaque a del unique destine a un feu de signalisation
US6853150B2 (en) * 2001-12-28 2005-02-08 Koninklijke Philips Electronics N.V. Light emitting diode driver
EP1590991A2 (fr) * 2003-01-23 2005-11-02 Gelcore LLC Modules de signalisation routiere a diodes electroluminescentes intelligentes
WO2005115058A1 (fr) * 2004-05-19 2005-12-01 Goeken Group Corp. Circuit de gradation pour del comprenant un moyen permettant de maintenir le courant dans un triac
WO2005120134A1 (fr) * 2004-06-03 2005-12-15 Philips Intellectual Property & Standards Gmbh Diodes electroluminescentes actionnees par un courant alternatif
DE102005023502B3 (de) * 2005-05-18 2006-12-21 Siemens Ag Schaltungsanordnung zur Stromversorgung von Leuchtdioden
FR2891106A1 (fr) * 2005-09-20 2007-03-23 Patrick Courteix Methode de connexion et d'alimentation de diodes electroluminescentes pour la realisation de lampes.
DE102006024607A1 (de) * 2006-05-26 2007-11-29 Bayerische Motoren Werke Ag Leuchtsystem
EP1675439A3 (fr) * 2004-12-21 2008-06-11 Richard Peter James Barton Luminaire pour alimentation pulsée
EP2079281A2 (fr) * 2008-01-14 2009-07-15 Tai-Her Yang Circuit de commande à diode électroluminescente bidirectionnelle dans une impédance à puissance bidirectionnelle divisée
EP2079284A2 (fr) * 2008-01-14 2009-07-15 Tai-Her Yang Circuit de commande à diode électroluminescente unidirectionnelle dans une non-résonance de puissance pulsée
EP2079279A2 (fr) * 2008-01-14 2009-07-15 Tai-Her Yang Circuit de commande à diode électroluminescente bidirectionnelle dans une résonance parallèle de puissance bidirectionnelle
EP2099259A1 (fr) * 2008-03-07 2009-09-09 Tai-Her Yang Procédé de commande de DEL de (DÉ)chargement unipolaire et circuit correspondant
EP2099260A1 (fr) * 2008-03-07 2009-09-09 Yang Tai-Her Procédé de commande de DEL de (DÉ)chargement unipolaire et circuit correspondant
WO2010146500A1 (fr) * 2009-06-17 2010-12-23 Koninklijke Philips Electronics N.V. Source de lumière atténuable à décalage de la température de lumière
WO2011009423A1 (fr) * 2009-07-21 2011-01-27 Paetzold Andre Corps d’éclairage
DE102010033640A1 (de) * 2010-08-06 2012-02-09 Austriamicrosystems Ag Schaltungsanordnung und Verfahren zum Betreiben von Leuchtdioden
WO2012052875A2 (fr) 2010-10-19 2012-04-26 Koninklijke Philips Electronics N.V. Lampe à diode électroluminescente pour conversion
US8174212B2 (en) 2008-11-30 2012-05-08 Microsemi Corp.—Analog Mixed Signal Group Ltd. LED string driver with light intensity responsive to input voltage
US8237590B2 (en) 2008-04-28 2012-08-07 GE Lighting Solutions, LLC Apparatus and method for reducing failures in traffic signals
EP2487997A1 (fr) * 2009-10-09 2012-08-15 Iurii N. Samoilenko Lampe à del
US8283875B2 (en) 2009-10-26 2012-10-09 Light-Based Technologies Incorporated Holding current circuits for phase-cut power control
CN103198791A (zh) * 2013-03-22 2013-07-10 深圳市天微电子有限公司 Led显示装置
EP2360993A3 (fr) * 2010-02-16 2013-12-25 Toshiba Lighting & Technology Corporation Dispositif électroluminescent avec affaiblissement du bruit et appareil d'éclairage doté de celui-ci
US8686668B2 (en) 2009-10-26 2014-04-01 Koninklijke Philips N.V. Current offset circuits for phase-cut power control
WO2014052858A1 (fr) * 2012-09-28 2014-04-03 Marvell World Trade Ltd. Circuit et procédé de limitation du courant pour circuit de pilotage de led
DE102013102312B3 (de) * 2013-03-08 2014-07-03 Vossloh-Schwabe Deutschland Gmbh Betriebsschaltung zum Betreiben eines Leuchtmoduls
EP2814302A1 (fr) * 2013-06-10 2014-12-17 OSRAM GmbH Module d'éclairage et système d'éclairage correspondant
GB2517455A (en) * 2013-08-20 2015-02-25 Harvard Engineering Plc Light Apparatus
US9088172B2 (en) 2008-06-17 2015-07-21 Koninklijke Philips N.V. Harmonic compensation circuit and method for an LED light unit
CN106102234A (zh) * 2016-07-04 2016-11-09 芯海科技（深圳）股份有限公司 一种led驱动电路
CN106686832A (zh) * 2017-02-24 2017-05-17 杰华特微电子（杭州）有限公司 一种二极管控制电路及开关电源电路
RU2621720C2 (ru) * 2012-03-15 2017-06-07 Филипс Лайтинг Холдинг Б.В. Шунтирующее устройство в системе управления освещением без нейтрального провода
EP3202415A2 (fr) 2010-06-30 2017-08-09 Compugen Ltd. C1orf32 fusionnée avec le fragment fc pour le traitement de la sclérose en plaques, la polyarthrite rhumatoïde et d'autres maladies auto-immunes
WO2017173453A1 (fr) 2016-04-01 2017-10-05 The Brigham And Women's Hospital, Inc. Nanoparticules sensibles aux stimuli pour applications biomédicales
TWI633806B (zh) * 2017-10-16 2018-08-21 鈺瀚科技股份有限公司 使用高電壓的發光二極體驅動電路
US20190174602A1 (en) * 2016-04-14 2019-06-06 Ledvance Gmbh Light fixture with at least one LED
US11284491B2 (en) 2011-12-02 2022-03-22 Lynk Labs, Inc. Color temperature controlled and low THD LED lighting devices and systems and methods of driving the same
US11297705B2 (en) 2007-10-06 2022-04-05 Lynk Labs, Inc. Multi-voltage and multi-brightness LED lighting devices and methods of using same
US11317495B2 (en) 2007-10-06 2022-04-26 Lynk Labs, Inc. LED circuits and assemblies
US11528792B2 (en) 2004-02-25 2022-12-13 Lynk Labs, Inc. High frequency multi-voltage and multi-brightness LED lighting devices
US11566759B2 (en) 2017-08-31 2023-01-31 Lynk Labs, Inc. LED lighting system and installation methods
US11638336B2 (en) 2004-02-25 2023-04-25 Lynk Labs, Inc. AC light emitting diode and AC LED drive methods and apparatus
US11678420B2 (en) 2004-02-25 2023-06-13 Lynk Labs, Inc. LED lighting system
US11953167B2 (en) 2011-08-18 2024-04-09 Lynk Labs, Inc. Devices and systems having AC LED circuits and methods of driving the same
US12279345B2 (en) 2009-12-28 2025-04-15 Lynk Labs, Inc. Light emitting diode and LED drive apparatus

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3676735A (en) * 1969-09-25 1972-07-11 Sylvania Electric Prod Resonator ballast for arc discharge lamps
US3869641A (en) * 1972-06-21 1975-03-04 Monsanto Co AC Responsive led pilot light circuitry
US4271408A (en) * 1978-10-17 1981-06-02 Stanley Electric Co., Ltd. Colored-light emitting display
US4321598A (en) * 1980-07-21 1982-03-23 The Singer Company Double density display drive system
US4517500A (en) * 1983-11-16 1985-05-14 Fmc Corporation Controller for electromagnetic exciter using power line subharmonic
US5187377A (en) * 1988-07-15 1993-02-16 Sharp Kabushiki Kaisha LED array for emitting light of multiple wavelengths
US5459478A (en) * 1993-12-27 1995-10-17 Illinois Tool Works, Inc. Aircraft cockpit switch circuitry

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3676735A (en) * 1969-09-25 1972-07-11 Sylvania Electric Prod Resonator ballast for arc discharge lamps
US3869641A (en) * 1972-06-21 1975-03-04 Monsanto Co AC Responsive led pilot light circuitry
US4271408A (en) * 1978-10-17 1981-06-02 Stanley Electric Co., Ltd. Colored-light emitting display
US4321598A (en) * 1980-07-21 1982-03-23 The Singer Company Double density display drive system
US4517500A (en) * 1983-11-16 1985-05-14 Fmc Corporation Controller for electromagnetic exciter using power line subharmonic
US5187377A (en) * 1988-07-15 1993-02-16 Sharp Kabushiki Kaisha LED array for emitting light of multiple wavelengths
US5459478A (en) * 1993-12-27 1995-10-17 Illinois Tool Works, Inc. Aircraft cockpit switch circuitry

Cited By (83)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10140331C2 (de) * 2001-08-16 2003-11-06 Siemens Ag Lichtzeichen zur Verkehrssteuerung und Verfahren zur Funktionsüberwachung eines solchen Zeichens
DE10140331A1 (de) * 2001-08-16 2003-04-03 Siemens Ag Lichtzeichen zur Verkehrssteuerung und Verfahren zur Funktionsüberwachung eines solchen Zeichens
US7129856B2 (en) 2001-08-16 2006-10-31 Siemens Aktiengesellschaft Illuminated sign for traffic control and method for functional monitoring of such a sign
US6853150B2 (en) * 2001-12-28 2005-02-08 Koninklijke Philips Electronics N.V. Light emitting diode driver
WO2004003869A1 (fr) * 2002-06-27 2004-01-08 Jose Monzo Dispositif d'emission lumineuse, en particulier dispositif d'emission lumineuse pour feux de signalisation, constitue de diodes electroluminescentes
DE10235811A1 (de) * 2002-06-27 2004-01-29 Jose Monzo Lichtabgabeeinrichtung, insbesondere Verkehrssignal-Lichtabgabeeinrichtung, die mit Leuchtdioden aufgebaut ist
DE10235811B4 (de) * 2002-06-27 2004-05-19 Jose Monzo Lichtabgabeeinrichtung, insbesondere Verkehrssignal-Lichtabgabeeinrichtung, die mit Leuchtdioden aufgebaut ist
EP1590991A4 (fr) * 2003-01-23 2006-07-19 Gelcore Llc Modules de signalisation routiere a diodes electroluminescentes intelligentes
EP1590991A2 (fr) * 2003-01-23 2005-11-02 Gelcore LLC Modules de signalisation routiere a diodes electroluminescentes intelligentes
WO2005001791A1 (fr) * 2003-06-30 2005-01-06 Koninklijke Philips Electronics N.V. Circuit d'attaque a del unique destine a un feu de signalisation
US11638336B2 (en) 2004-02-25 2023-04-25 Lynk Labs, Inc. AC light emitting diode and AC LED drive methods and apparatus
US11528792B2 (en) 2004-02-25 2022-12-13 Lynk Labs, Inc. High frequency multi-voltage and multi-brightness LED lighting devices
US11678420B2 (en) 2004-02-25 2023-06-13 Lynk Labs, Inc. LED lighting system
US7872427B2 (en) 2004-05-19 2011-01-18 Goeken Group Corp. Dimming circuit for LED lighting device with means for holding TRIAC in conduction
WO2005115058A1 (fr) * 2004-05-19 2005-12-01 Goeken Group Corp. Circuit de gradation pour del comprenant un moyen permettant de maintenir le courant dans un triac
AU2005246918B2 (en) * 2004-05-19 2010-04-29 The Andrew Molasky Family Limited Partnership Dimming circuit for LED lighting device with means for holding triac in conduction
JP2013145909A (ja) * 2004-06-03 2013-07-25 Koninkl Philips Electronics Nv 発光ダイオードを有する回路
US9060398B2 (en) 2004-06-03 2015-06-16 Koninklijke Philips N.V. Lighting device employing ac-driven light-emitting diodes
US8084945B2 (en) 2004-06-03 2011-12-27 Koninklijke Philips Electronics N.V. AC driven light-emitting diodes
WO2005120134A1 (fr) * 2004-06-03 2005-12-15 Philips Intellectual Property & Standards Gmbh Diodes electroluminescentes actionnees par un courant alternatif
US8456089B2 (en) 2004-06-03 2013-06-04 Koninklijke Philips Electronics N.V. AC driven light-emitting diodes
EP1675439A3 (fr) * 2004-12-21 2008-06-11 Richard Peter James Barton Luminaire pour alimentation pulsée
DE102005023502B3 (de) * 2005-05-18 2006-12-21 Siemens Ag Schaltungsanordnung zur Stromversorgung von Leuchtdioden
FR2891106A1 (fr) * 2005-09-20 2007-03-23 Patrick Courteix Methode de connexion et d'alimentation de diodes electroluminescentes pour la realisation de lampes.
DE102006024607A1 (de) * 2006-05-26 2007-11-29 Bayerische Motoren Werke Ag Leuchtsystem
US11729884B2 (en) 2007-10-06 2023-08-15 Lynk Labs, Inc. LED circuits and assemblies
US11297705B2 (en) 2007-10-06 2022-04-05 Lynk Labs, Inc. Multi-voltage and multi-brightness LED lighting devices and methods of using same
US12213224B2 (en) 2007-10-06 2025-01-28 Lynk Labs, Inc. Multi-voltage and multi-brightness LED lighting devices and methods of using same
US11317495B2 (en) 2007-10-06 2022-04-26 Lynk Labs, Inc. LED circuits and assemblies
EP2079279A2 (fr) * 2008-01-14 2009-07-15 Tai-Her Yang Circuit de commande à diode électroluminescente bidirectionnelle dans une résonance parallèle de puissance bidirectionnelle
EP2079279A3 (fr) * 2008-01-14 2011-03-30 Tai-Her Yang Circuit de commande à diode électroluminescente bidirectionnelle dans une résonance parallèle de puissance bidirectionnelle
EP2079281A3 (fr) * 2008-01-14 2011-03-30 Tai-Her Yang Circuit de commande à diode électroluminescente bidirectionnelle dans une impédance à puissance bidirectionnelle divisée
EP2079281A2 (fr) * 2008-01-14 2009-07-15 Tai-Her Yang Circuit de commande à diode électroluminescente bidirectionnelle dans une impédance à puissance bidirectionnelle divisée
EP2079284A3 (fr) * 2008-01-14 2011-03-30 Tai-Her Yang Circuit de commande à diode électroluminescente unidirectionnelle dans une non-résonance de puissance pulsée
EP2079284A2 (fr) * 2008-01-14 2009-07-15 Tai-Her Yang Circuit de commande à diode électroluminescente unidirectionnelle dans une non-résonance de puissance pulsée
EP2099260A1 (fr) * 2008-03-07 2009-09-09 Yang Tai-Her Procédé de commande de DEL de (DÉ)chargement unipolaire et circuit correspondant
EP2099259A1 (fr) * 2008-03-07 2009-09-09 Tai-Her Yang Procédé de commande de DEL de (DÉ)chargement unipolaire et circuit correspondant
US8237590B2 (en) 2008-04-28 2012-08-07 GE Lighting Solutions, LLC Apparatus and method for reducing failures in traffic signals
US9088172B2 (en) 2008-06-17 2015-07-21 Koninklijke Philips N.V. Harmonic compensation circuit and method for an LED light unit
US8174212B2 (en) 2008-11-30 2012-05-08 Microsemi Corp.—Analog Mixed Signal Group Ltd. LED string driver with light intensity responsive to input voltage
WO2010146500A1 (fr) * 2009-06-17 2010-12-23 Koninklijke Philips Electronics N.V. Source de lumière atténuable à décalage de la température de lumière
US8633650B2 (en) 2009-06-17 2014-01-21 Koninklijke Philips N.V. Dimmable light source with light temperature shift
CN102460560A (zh) * 2009-06-17 2012-05-16 皇家飞利浦电子股份有限公司 具有光温漂移的可调光源
CN102550127A (zh) * 2009-07-21 2012-07-04 安德烈·佩特佐尔德 发光体
WO2011009423A1 (fr) * 2009-07-21 2011-01-27 Paetzold Andre Corps d’éclairage
EP2487997A4 (fr) * 2009-10-09 2013-07-17 Iurii N Samoilenko Lampe à del
EP2487997A1 (fr) * 2009-10-09 2012-08-15 Iurii N. Samoilenko Lampe à del
US8339066B2 (en) 2009-10-26 2012-12-25 Light-Based Technologies Incorporated Energy saving lighting systems and units providing coordinated operation of holding current units
US8686668B2 (en) 2009-10-26 2014-04-01 Koninklijke Philips N.V. Current offset circuits for phase-cut power control
US8283875B2 (en) 2009-10-26 2012-10-09 Light-Based Technologies Incorporated Holding current circuits for phase-cut power control
US12279345B2 (en) 2009-12-28 2025-04-15 Lynk Labs, Inc. Light emitting diode and LED drive apparatus
EP2360993A3 (fr) * 2010-02-16 2013-12-25 Toshiba Lighting & Technology Corporation Dispositif électroluminescent avec affaiblissement du bruit et appareil d'éclairage doté de celui-ci
US8716943B2 (en) 2010-02-16 2014-05-06 Toshiba Lighting And Technology Corporation Light-emitting device and lighting apparatus provided with the same
EP3202415A2 (fr) 2010-06-30 2017-08-09 Compugen Ltd. C1orf32 fusionnée avec le fragment fc pour le traitement de la sclérose en plaques, la polyarthrite rhumatoïde et d'autres maladies auto-immunes
DE102010033640A1 (de) * 2010-08-06 2012-02-09 Austriamicrosystems Ag Schaltungsanordnung und Verfahren zum Betreiben von Leuchtdioden
DE102010033640B4 (de) 2010-08-06 2018-07-12 Austriamicrosystems Ag Schaltungsanordnung und Verfahren zum Betreiben von Leuchtdioden sowie Beleuchtungsanordnung
US9253828B2 (en) 2010-08-06 2016-02-02 Ams Ag Circuit arrangement and method for operating light-emitting diodes
CN103181241A (zh) * 2010-10-19 2013-06-26 皇家飞利浦电子股份有限公司 Led改装灯
US9095023B2 (en) 2010-10-19 2015-07-28 Koninklijke Philips N.V. LED retrofit lamp
WO2012052875A2 (fr) 2010-10-19 2012-04-26 Koninklijke Philips Electronics N.V. Lampe à diode électroluminescente pour conversion
WO2012052875A3 (fr) * 2010-10-19 2012-06-14 Koninklijke Philips Electronics N.V. Lampe à diode électroluminescente pour conversion
JP2013543642A (ja) * 2010-10-19 2013-12-05 コーニンクレッカ フィリップス エヌ ヴェ Ｌｅｄレトロフィットランプ
US11953167B2 (en) 2011-08-18 2024-04-09 Lynk Labs, Inc. Devices and systems having AC LED circuits and methods of driving the same
US12028947B2 (en) 2011-12-02 2024-07-02 Lynk Labs, Inc. Color temperature controlled and low THD LED lighting devices and systems and methods of driving the same
US11284491B2 (en) 2011-12-02 2022-03-22 Lynk Labs, Inc. Color temperature controlled and low THD LED lighting devices and systems and methods of driving the same
RU2621720C2 (ru) * 2012-03-15 2017-06-07 Филипс Лайтинг Холдинг Б.В. Шунтирующее устройство в системе управления освещением без нейтрального провода
US9306387B2 (en) 2012-09-28 2016-04-05 Marvell World Trade Ltd. Current limiting circuit and method for LED driver
WO2014052858A1 (fr) * 2012-09-28 2014-04-03 Marvell World Trade Ltd. Circuit et procédé de limitation du courant pour circuit de pilotage de led
DE102013102312B3 (de) * 2013-03-08 2014-07-03 Vossloh-Schwabe Deutschland Gmbh Betriebsschaltung zum Betreiben eines Leuchtmoduls
CN103198791A (zh) * 2013-03-22 2013-07-10 深圳市天微电子有限公司 Led显示装置
US9398658B2 (en) 2013-06-10 2016-07-19 Osram Gmbh Lighting module and corresponding lighting system
EP2814302A1 (fr) * 2013-06-10 2014-12-17 OSRAM GmbH Module d'éclairage et système d'éclairage correspondant
GB2517455A (en) * 2013-08-20 2015-02-25 Harvard Engineering Plc Light Apparatus
GB2517455B (en) * 2013-08-20 2016-11-02 Harvard Eng Plc Lighting Apparatus
WO2017173453A1 (fr) 2016-04-01 2017-10-05 The Brigham And Women's Hospital, Inc. Nanoparticules sensibles aux stimuli pour applications biomédicales
US20190174602A1 (en) * 2016-04-14 2019-06-06 Ledvance Gmbh Light fixture with at least one LED
US11805579B2 (en) * 2016-04-14 2023-10-31 Ledvance Gmbh Light fixture with at least one LED
CN106102234A (zh) * 2016-07-04 2016-11-09 芯海科技（深圳）股份有限公司 一种led驱动电路
CN106686832B (zh) * 2017-02-24 2019-04-02 杰华特微电子（杭州）有限公司 一种二极管控制电路及开关电源电路
CN106686832A (zh) * 2017-02-24 2017-05-17 杰华特微电子（杭州）有限公司 一种二极管控制电路及开关电源电路
US11566759B2 (en) 2017-08-31 2023-01-31 Lynk Labs, Inc. LED lighting system and installation methods
US12104766B2 (en) 2017-08-31 2024-10-01 Lynk Labs, Inc. LED lighting system and installation methods
TWI633806B (zh) * 2017-10-16 2018-08-21 鈺瀚科技股份有限公司 使用高電壓的發光二極體驅動電路

Also Published As

Publication number Publication date
AU4850099A (en) 2001-01-31

Similar Documents

Publication Publication Date Title
WO2001001385A1 (fr) Circuits a reseau de diodes electroluminescentes alimentes en courant alternatif pour afficheurs d'appareils de signalisation
US5936599A (en) AC powered light emitting diode array circuits for use in traffic signal displays
US7333027B2 (en) Power supply for LED signal
US7710050B2 (en) Series connected power supply for semiconductor-based vehicle lighting systems
US8841862B2 (en) LED driving system and method for variable voltage input
US4349863A (en) Emergency lighting system
KR100948736B1 (ko) 교류 위상제어방식을 이용한 발광다이오드 조명장치 및 그를 채용한 발광다이오드 조명장치 관리 시스템
US20110085271A1 (en) LED Modules for Sign Channel Letters and Driving Circuit
US8294371B2 (en) LED traffic signal with synchronized power pulse circuit
WO2010065005A1 (fr) Lampe à diodes électroluminescentes
US10390394B2 (en) Solid-state lighting with an interface between an internal control voltage and an external voltage
RU2572048C1 (ru) Светодиодная лампа для железнодорожного светофора с реактивным балластом
EP3970453B1 (fr) Topologie de puissance partagée pour les luminaires à led
KR20160077718A (ko) 3상 교류전원용 led 구동회로, led 조명장치 및 이를 포함하는 led 조명 시스템
RU2329619C1 (ru) Светодиодный осветитель
JP3885741B2 (ja) 照明システム、放電灯点灯装置、照明器具
US10869373B2 (en) Solid-state lighting with highly integrated drivers
US10645782B2 (en) Solid-state lighting with emergency power management
US11264831B2 (en) Solid-state lighting with an emergency driver
CA3116919A1 (fr) Systeme et procede de reconversion d'architecture de cablage 120 vac pour une gradation de del a deux fils de puissance en courant continu a basse tension modernisable
RU2660842C2 (ru) Светодиодная лампа для железнодорожного светофора с реактивно-импульсным балластом
US12163631B1 (en) Solid state lighting driver and lamp replacement for avionics ballast and fluorescent lamp
EP4123873A1 (fr) Dispositif d'alimentation pour l'alimentation sans fil d'énergie électrique à un luminaire de secours et luminaire de secours
JPH01253195A (ja) 照明装置
JP2020107436A (ja) 照明制御システム及び照明システム

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SL SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
ENP Entry into the national phase

Ref country code: AT

Ref document number: 2000 9149

Date of ref document: 20010301

Kind code of ref document: A

Format of ref document f/p: F

WWE Wipo information: entry into national phase

Ref document number: 20009149

Country of ref document: AT

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
点击 这是indexloc提供的php浏览器服务，不要输入任何密码和下载