CN103680881B - A kind of adjustable transformer and rank difference pressure regulation method thereof - Google Patents

Abstract

A voltage regulating transformer of the present invention includes a main transformer body and a series transformer body; the main transformer body includes a main transformer common coil and a main transformer series coil connected in series with the incoming line end, and is connected with the main transformer common coil and the main transformer The main transformer voltage regulating coil with electromagnetic coupling of serial coils; the series transformer body includes a series transformer primary coil and a serial transformer secondary coil electromagnetically coupled to each other; the series transformer primary coil is connected in series with the main transformer voltage regulating coil, The secondary coil of the series transformer on the series coil of the transformer is connected with the outlet terminal. The level difference voltage regulating method of the voltage regulating transformer of the present invention comprises the following steps, the step of changing the transmission voltage in the secondary coil of the series transformer by adjusting the number of connected turns of the main transformer series coil; by adjusting the connected turns of the main transformer voltage regulating coil The step of changing the induced voltage in the secondary coil of the series transformer; the step of changing the outlet voltage of the voltage regulating transformer by adjusting the induction voltage and/or the transmission voltage; wherein the outlet voltage is equal to the algebraic sum of the transmission voltage and the induction voltage.

Description

A voltage-regulating transformer and its step-difference voltage-regulating method

technical field

The invention relates to the technical field of transformer voltage regulation, in particular to a voltage regulation transformer and a level difference voltage regulation method thereof.

Background technique

In the prior art, the voltage regulation series of special transformers used in metallurgy and other industrial production is limited by the load voltage and current of the tap changer, the voltage regulation range is small, the flexibility is poor, and it cannot meet the needs of users; at the same time, due to the existing technology Due to the limitation of the structure of the voltage regulation method of the special transformer, the main transformer and the voltage regulation transformer are arranged in one oil tank. Therefore, with the increase of the capacity and voltage regulation range, the volume and weight also increase greatly, which brings great difficulties to transportation, installation and maintenance. Big inconvenience.

Contents of the invention

In order to solve the problems in the prior art, the present invention provides a voltage regulating transformer, which separates the voltage regulating transformer from the rectifying transformer, and has a unique structure and compact volume.

The present invention also has a corresponding step-difference pressure regulation method, with flexible pressure regulation methods and a large pressure regulation range.

The present invention is achieved through the following technical solutions:

A voltage regulating transformer, including a main transformer body and a series transformer body; the main transformer body includes a main transformer common coil and a main transformer series coil connected in series with an incoming line end, and a main transformer common coil and a main transformer coil The main transformer voltage regulating coil with electromagnetic coupling of series coils; the series transformer body includes a series transformer primary coil and a serial transformer secondary coil that are electromagnetically coupled to each other; the series transformer primary coil is connected in series with the main transformer voltage regulating coil, The secondary coil of the series transformer on the series coil is connected with the outlet terminal.

Preferably, the series coil of the main transformer is connected and disconnected through an off-excitation tap changer, and the series coil of the main transformer is connected to the secondary coil of the series transformer through an auto-coupling voltage regulation through an off-excitation tap changer.

Furthermore, the series coil of the main transformer is connected in series with the corresponding phases of the secondary coil of the series transformer through three single-phase off-excitation tap-changers.

Preferably, the voltage regulating coil of the main transformer is connected and disconnected by an on-load tap changer provided with a polarity selection switch.

Furthermore, the voltage regulating coil of the main transformer is connected in series with the primary coil of the series transformer through a three-phase on-load tap changer.

Preferably, both the main transformer body and the series transformer body adopt a three-phase three-column body structure, and are arranged in the same oil tank.

The present invention is based on the level difference voltage regulating method of the voltage regulating transformer described in the present invention, comprising the following steps, the step of changing the transmission voltage in the secondary coil of the series transformer by adjusting the number of connected turns of the series coil of the main transformer; The step of changing the induced voltage in the secondary coil of the series transformer by connecting the number of turns of the voltage regulating coil; the step of changing the voltage at the outlet terminal of the voltage regulating transformer by adjusting the induced voltage and/or the transmission voltage; wherein the voltage at the outlet terminal is equal to the difference between the transmission voltage and the induced voltage Algebraic sum.

Preferably, the maximum number of gear adjustment stages of the step-difference voltage regulation is equal to the product of the gear stages of the series coil of the main transformer and the gear stages of the main transformer voltage regulating coil.

Preferably, the number of connected turns of the series coil of the main transformer is adjusted by gear selection of the off-excitation tap changer.

Preferably, the number of connected turns of the voltage regulating coil of the main transformer is adjusted by gear selection of the on-load tap changer.

Compared with the prior art, the present invention has the following beneficial technical effects:

The voltage regulating transformer of the present invention generates an induced voltage on the main transformer voltage regulating coil through the electromagnetic coupling relationship between the main transformer voltage regulating coil, the main transformer common coil and the main transformer series coil, and taps the main transformer voltage regulating coil. Connecting and disconnecting adjusts the loading voltage on the primary coil of the series transformer, and adjusts the induced voltage on the secondary coil of the serial transformer through the electromagnetic coupling relationship between the primary coil of the serial transformer and the secondary coil of the serial transformer; through the common coil of the main transformer and the The self-coupling voltage regulation method of the series coil of the main transformer adjusts the transmission voltage directly transmitted to the secondary coil of the series transformer, thereby comprehensively realizing the control and adjustment of the output terminal voltage. The structure is unique, the operation is simple, and the voltage regulation range is large. It also ensures the constant output current at the outlet end, improves the stability of the product, and greatly reduces the loss of the transformer.

Further, by selecting the voltage regulation mode and switch configuration and then matching the corresponding lead wire structure, the user's requirements for voltage regulation and tapping of the product are met; thus, the voltage regulation transformer is separated from the rectifier transformer, so that a single voltage regulation transformer can cooperate with The use of multiple rectifier transformers not only reduces the volume and weight of a single rectifier transformer, ensures transportation, but also reduces consumption of materials for users, and reduces production costs for current and future transformation or replacement of equipment.

The step-difference voltage regulation method of the voltage regulation transformer described in the present invention is carried out by apportioning the regulation of the outlet terminal voltage to two voltage regulation links, and using the turns connected with the series coil of the main transformer and the voltage regulation coil of the main transformer respectively. Removal and coordination adjustment, the adjustment through the series coil of the main transformer is coarse adjustment, and the adjustment through the voltage regulating coil of the main transformer is fine adjustment, so that the gear series of the voltage regulation is the product of the series of the gear positions of the two voltage regulating links, which is equivalent to Compared with the prior art, the step-difference pressure regulation with a wider range and more stages is realized.

Further, through the selection of the main transformer series coil and the main transformer voltage regulating coil voltage regulating switch, the safety and stability of the circuit when a large current flows through the main transformer series coil is ensured, and the continuous power supply can be realized in the main transformer voltage regulating coil. Adjustment of outgoing terminal voltage under load operation

Description of drawings

Fig. 1 is a winding connection diagram of the voltage regulating transformer of the present invention.

In the figure: Ⅰ is the body of the main transformer, Ⅱ is the body of the series transformer, A, B, and C are the three-phase incoming terminals, a, b, and c are the three-phase outgoing terminals, and Am, Bm, and Cm are the main transformer and voltage regulating coils am, bm, and cm are the input terminals of the primary coil of the series transformer, k1-k3 are the polarity selection switches, G1-G3 are the common coils of the main transformer, C1-C3 are the series coils of the main transformer, and T1-T3 are the main Transformer and voltage regulator coils, H1-H3 are primary coils for series transformers, and L1-L3 are secondary coils for serial transformers.

detailed description

The present invention will be further described in detail below in conjunction with specific examples, which are explanations of the present invention rather than limitations.

A voltage regulating transformer of the present invention, as shown in Figure 1, includes a main transformer body and a series transformer body; the main transformer body includes main transformer series coils C1, C2, C3, main transformer common coils G1, G2, G3 and Main transformer voltage regulating coils T1, T2, T3; series transformer body includes series transformer primary coils H1, H2, H3 and series transformer secondary coils L1, L2, L3.

In this preferred embodiment, as shown in Figure 1, the incoming line terminals A, B, and C are respectively connected in series with the C1, C2, and C3 coils, and the C1, C2, and C3 coils are respectively connected in series with the G1, G2, and G3 coils and passed through three The single-phase non-excitation tap-changer is connected with L1, L2, L3 coils to form an auto-coupling voltage regulation connection; Coupling relationship, T1, T2, T3 coils are connected in series with H1, H2, H3 coils respectively through a three-phase on-load tap-changer, H1, H2, H3 coils and L1, L2, L3 coils are respectively electromagnetic coupling relationship, L1, The L2 and L3 coils are respectively connected to the outlet terminals a, b and c. The body of the main transformer and the body of the series transformer both adopt a three-phase three-column body structure and are arranged in the same oil tank.

In this preferred embodiment based on the voltage regulating transformer and its level difference voltage regulating method of the present invention, it includes the following steps, changing the transmission voltage in L1, L2, L3 coils by adjusting the access turns of C1, C2, C3 coils The steps; the steps of changing the induced voltages in the L1, L2, and L3 coils by adjusting the number of turns of the T1, T2, and T3 coils; the steps of changing the voltage at the outlet terminal of the voltage regulating transformer by adjusting the induced voltage and/or the transmission voltage; wherein the outlet terminal The voltage is equal to the algebraic sum of the transmitted voltage and the induced voltage.

Wherein, the maximum adjustment stages of the gear positions of the step difference voltage regulation is equal to the product of the gear stages of the C1, C2, C3 coils and the gear stages of the T1, T2, T3 coils. In this preferred embodiment, the access and removal of coil turns of C1, C2, and C3 are adjusted by off-excitation tap-changer; the access and removal of coil turns of T1, T2, and T3 are adjusted by on-load tap-changer adjust.

Specifically, as shown in Figure 1, both the main transformer body I and the series transformer body II adopt a three-phase three-column body structure. The self-coupling off-excitation voltage regulation part, as shown in Figure 1, uses a 5-level linear voltage regulation as the coarse adjustment, and because the current on the input side is relatively large, so three single-phase off-excitation tap-changers are selected to ensure a large current output to meet the demand. The on-load voltage regulation part, as shown in Figure 1, uses a total of 35 levels of positive and negative voltage regulation as fine adjustment. Since the capacity of the series transformer body can be designed to be small, H1, H2, and H3 in the series transformer body Coils, and the currents of T1, T2, and T3 coils in the main transformer body are also small, so a three-phase on-load tap-changer can be selected.

When working, the T1, T2, and T3 coils on the main transformer respectively supply power to the H1, H2, and H3 coils connected in series, and the L1, L2, and L3 coils that are electromagnetically coupled to the H1, H2, and H3 coils respectively induce the The induced voltage is a part of the voltage at the outlet terminal, and the algebraic sum of the transmission voltage directly output from the C1, C2, C3 coils and G1, G2, G3 coils to the L1, L2, and L3 coils respectively is the actual output voltage at the outlet terminal, so The output voltage at the outlet end can be adjusted stably in a wide range, and the on-load uninterruptible power level difference adjustment of the voltage can be realized in each gear of the off-excitation tap changer.

When a constant AC voltage is applied to the C1, C2, C3 coils and G1, G2, G3 coils in the main transformer body from the incoming line end, different C1, C2, C3 coil taps are selected through three off-excitation tap changers. Then a variable transmission voltage is directly output through the L1, L2, L3 coils connected with the off-excitation tap changer, and the output direct transmission voltage is a part of the output terminal voltage.

When a constant AC voltage is applied to the C1, C2, C3 coils and G1, G2, G3 coils in the main transformer body from the incoming line end, since the T1, T2, T3 coils in the main transformer body are connected in series with the corresponding The C1, C2, C3 coils and G1, G2, G3 coils are electromagnetically coupled, and the T1, T2, T3 coils will generate an induced output voltage. Connected to the switch to adjust, the output voltage level difference can be evenly changed. At the same time, coils H1, H2, and H3 are connected in series with coils T1, T2, and T3 respectively, so the output voltage is also the input voltage of coils H1, H2, and H3, and the level difference can also be changed evenly. The L1, L2, and L3 coils in the series converter body are electromagnetically coupled with the H1, H2, and H3 coils respectively, and the output terminals of the L1, L2, and L3 coils will also generate induced output voltages, and the level difference can also be uniformly changed. The induced voltage at this output is another part of the voltage at the outgoing terminals.

The direct output transmission voltage and the output induced voltage are connected in series, and the algebraic sum of the two is the actual output voltage at the outlet. The number of voltage regulation stages is the product of the number of gears of the off-excitation tap-changer and the number of gears of the on-load tap-changer. Level 175 obtained by accumulating files. When a constant voltage is applied to the input side of the voltage regulating transformer, the output voltage and power of the output side can change uniformly and smoothly in a wide range; and in each gear of the off-excitation tap changer, it can realize 35 levels of on-load uninterruptible power supply differential pressure change. Moreover, the output current at the output terminal of the transformer output side remains constant.

Claims (8)

1. an adjustable transformer, it is characterised in that include main transformer device body and string becomes device body；Described main transformer device body includes the main transformer common winding with end of incoming cables series winding and main transformer series coil, with the main transformer voltage regulation coil of main transformer common winding and main transformer series coil electromagnetic coupled；Described string change device body includes the string change primary winding of mutual electromagnetic coupling and becomes secondary coil with string；String becomes primary winding and connects with main transformer voltage regulation coil, is connected on the change secondary coil of the string on main transformer series coil and is connected with leading-out terminal；

Described main transformer series coil is accessed by off circuit tap changer and excises, and main transformer series coil becomes secondary coil self-coupling by off circuit tap changer with string and is connected；

Described main transformer voltage regulation coil becomes primary winding by a three-phase load ratio bridging switch with string and connects.

2. a kind of adjustable transformer according to claim 1, it is characterised in that described main transformer series coil becomes the corresponding of secondary coil with string respectively by three single-phase excitation-free tapping switchs and is in series.

3. a kind of adjustable transformer according to claim 1, it is characterised in that described main transformer voltage regulation coil adopts the load ratio bridging switch being provided with polar selecting switch to access and excision.

4. a kind of adjustable transformer according to claim 1, it is characterised in that described main transformer device body and string become device body and all adopt three-phase three-limb machine body structure, and are arranged in same fuel tank.

5. the rank difference pressure regulation method based on adjustable transformer described in claim 1, it is characterised in that comprise the steps,

The step transmitting voltage in string change secondary coil by regulating the access number of turn of main transformer series coil to change；The step of induced voltage in string change secondary coil is changed by regulating the access number of turn of main transformer voltage regulation coil；By regulating induced voltage and/or the step of transmission voltage change adjustable transformer outlet voltage；Wherein outlet voltage is equal to the algebraical sum of transmission voltage with induced voltage.

6. the rank difference pressure regulation method of a kind of adjustable transformer according to claim 5, it is characterised in that the gear maximal regulated progression of rank difference pressure regulation is long-pending with the gear progression of main transformer voltage regulation coil equal to the gear progression of main transformer series coil.

7. the rank difference pressure regulation method of a kind of adjustable transformer according to claim 5, it is characterised in that the access number of turn of main transformer series coil is regulated by off circuit tap changer gear selecting.

8. the rank difference pressure regulation method of a kind of adjustable transformer according to claim 5, it is characterised in that the access number of turn of main transformer voltage regulation coil is regulated by load ratio bridging switch gear selecting.