JP3829529B2 - Peak cut controller - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for controlling an energization current of a monitoring circuit to be less than a set current value.
[0002]
[Prior art]
The peak cut controller prevents power outages due to the operation of the circuit breaker by automatically turning on / off the control target device or control target circuit when the current flowing through the monitoring circuit exceeds the set current. Is. The conventional return current value is fixed with respect to the current set value.
[0003]
[Problems to be solved by the invention]
In the conventional peak cut controller described above, the return current value is fixed with respect to the current setting value, so the return condition is set appropriately depending on the amount of current used by the connected control target device or control target circuit. There wasn't. For example, if the control target device or control target circuit has a large operating current, such as a large device, the energization current may exceed the set current upon return, and the “off” control state may be entered again. We must stop using equipment and other electrical equipment.
[0004]
An object of the present invention is to provide a peak cut controller that sets a return current so that an energization current of a monitoring circuit is less than a current setting value even when the control target device or the control target circuit returns.
[0005]
[Means for Solving the Problems]
The invention of claim 1 includes a current transformer 1 that detects the current flowing in the monitoring circuit, a current measuring circuit 2 that receives the signal from the current transformer 1 and measures the current flowing, and an upper limit of the current flowing in the monitoring circuit ( Hereinafter, when the current setting circuit 3 for setting the current setting circuit 3 and the control target device or the control target circuit are in a stopped or cut-off state, the current to be supplied to the monitoring circuit is kept below a certain current value or the control target device or A return current setting circuit 4 for setting a return current such that the control target circuit returns, a comparison circuit 5 for comparing an energization current value from the current measurement circuit 2 with a set current value from the current setting circuit 3, In a peak cut controller comprising a current control circuit 6 that receives a signal from the comparison circuit 5 and performs “on” and “off” control of the control target device or control target circuit, the energization current of the control target device or control target circuit The Even if the control target energizing current measuring means 7 to be determined and the control target device or control target circuit return after the “off” control by the current control circuit 6, the energizing current of the monitoring circuit does not exceed the set current value. A return current setting circuit 4 for setting a return current is provided.
[0006]
According to a second aspect of the present invention, in the peak cut controller according to the first aspect, the control target energization current measuring means 7 determines whether the control target device or the energization target circuit has a current value of a certain time before and after the operation of the current control circuit. The control object energization current measuring circuit 10 for calculating the energization current is provided.
[0007]
[Action]
According to the configuration of claim 1, when an overcurrent exceeding the set value flows through the electric circuit and returns from the “off” state by the current control unit, the control target device or the control target is controlled using the control target energization current measurement unit. By measuring the energization current of the circuit, there is an effect of setting the return current value so that the energization current of the monitoring circuit does not exceed the set current even when the control target device or the control target circuit recovers.
[0008]
According to the configuration of the second aspect, in addition to the effects of the first aspect, the energization current of the control target device or the control target circuit is calculated from the difference in the energization current of the monitoring circuit before and after the current control circuit operates. Therefore, there is an effect of omitting the arrangement of the energization current measuring device to each control target device or control target circuit.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0010]
FIG. 1 is a block diagram showing the configuration of the peak cut controller according to claim 1, and includes a current transformer 1, a current measurement circuit 2, a current setting circuit 3, a comparison circuit 5, a current control circuit 6 and the like as main components. . The monitoring electric circuit 10 connected to the overcurrent breaker including the contact points shows a single-phase three-wire type.
[0011]
The current transformer 1 detects an electric current flowing through the monitoring electric circuit 10 and outputs an alternating current. When the monitoring circuit 10 is a single-phase three-wire system, it is necessary to detect the amount of current at both ends, so two current transformers are passed through the wires at both ends, and the output waveform of the current transformer 1 is the monitoring circuit 10. It is proportional to the differential value of the current flow waveform.
[0012]
The current measurement circuit 2 is a circuit that measures a signal from the current transformer 1 as an energization current value of the monitoring circuit.
[0013]
The current setting circuit 3 is a circuit that sets an upper limit of the energization current in the monitoring electric circuit, and is set using, for example, a switch. Generally, the current value is set such that the overcurrent breaker connected to the monitoring circuit is difficult to operate.
[0014]
The comparison circuit 5 compares the signals from the current measurement circuit 2 and the current setting circuit 3, and outputs a signal corresponding to the overcurrent to the current control circuit 6 when the energization current of the monitoring circuit exceeds the current setting value. To do. In addition, after the control target device or the control target circuit is “off” controlled by the current control circuit 6, the current measurement circuit 2 and the signal from the return current setting circuit 4 are compared, and the conduction current is less than the return current value. If it continues, a signal is output to the current control circuit 6.
[0015]
The current control circuit 6 receives the signal from the comparison circuit 5 and controls the control target device or the control target circuit according to the signal. For example, when the energization current of the monitoring circuit exceeds the current set value, the plurality of control target devices or control target circuits are stopped or shut off in order according to a predetermined order. Further, when the energization current of the monitoring circuit continues to be less than the return current value, the plurality of control target devices or control target circuits are returned in accordance with a predetermined order. The control target device or the control target circuit may be a single unit.
[0016]
The control target energization current measuring means 7 measures the currents used in each connected control target device or control target circuit. For example, a current measuring unit is arranged in each control target device or control target circuit, and a method of measuring the current used by the control target device or control target circuit is taken.
[0017]
The return current setting circuit 4 sets the return current value so that the energization current of the monitoring circuit is less than the set current value even if the control target device or control target circuit in the `` OFF '' control state is returned by the current control circuit. Set. For example, if the return current value is a value obtained by subtracting the energization current value of the control target device or control target circuit received from the control target energization current measurement circuit from the set current value, the control target device or control target circuit is recovered. Also, a return current value is obtained so that the energization current of the monitoring circuit does not exceed the current set value.
[0018]
FIG. 4 is a flowchart of the peak cut controller function, and shows operation programs of the comparison circuit 5, the current control circuit 6, the control target energization current measuring means 7, and the return current setting circuit 4. Reference numeral 11 denotes a step of reading the energized current value from the current measuring circuit 2 and the current set value from the current setting circuit 3. 12 is a step for determining whether the energization current of the monitoring circuit has reached the set current, and 13 is for outputting a predetermined process so that the energization current of the monitoring circuit is less than the set current value in accordance with the amount of the energization current that has been exceeded. It is a step. 14 is a step of receiving a signal from 13 and outputting a stop or shut-off signal for the control target device or control target circuit. 15 is a step of setting a return current from the measured energization current of the control target device or control target circuit. 16 is a step for judging whether the energization current of the monitoring circuit is below the return current value, and 17 is a step for outputting the return of the controlled device or control target circuit that has been stopped or shut off. If “NO” is determined in steps 12 and 16, the process is repeated until the condition is satisfied through the route indicated by the arrow “NO”.
[0019]
With this configuration, the energization current of each control target is measured, and the energization current of the monitoring circuit does not exceed the current setting value even when the energization current of the controlled device or circuit is restored. You can get a peak cut controller to set.
[0020]
Next, a second embodiment of the present invention will be described with reference to FIG. This embodiment is different from the first embodiment in that a control target energization current measuring circuit is arranged, and the other parts are almost the same, so that the description thereof is omitted. In addition, the same number is attached | subjected about the common part as FIG.
[0021]
The control target energization current measurement circuit 10 monitors the energization current of each control target device or control target circuit connected to the branch circuit. For example, when a control target device or control target circuit having a current control circuit is stopped or shut off, the energization current of the monitoring circuit changes as shown in FIG. Assuming that the time of the stop or shut-off is T, the times before and after the time T are t1 and t2, and the average currents of the times t1 and t2 are I1 and I2, respectively, the energization current of the controlled device or circuit to be controlled I is expressed as I = I2−I1 and can be calculated.
[0022]
The return current setting circuit 4 sets the return current value so that the energization current of the monitoring circuit is less than the set current value even when the control target device or the control target circuit in the “OFF” state is returned by the current control circuit 6. Set. For example, if the return current value is a value obtained by subtracting the energization current value of the control target device or the control target circuit received from the control target energization current measurement circuit 10 from the set current value, the control target device or the control target circuit is recovered. However, the return current value that does not exceed the current setting value is obtained for the energization current of the monitoring circuit.
[0023]
FIG. 5 is a flowchart for setting the return current, which corresponds to 15 steps of the first embodiment. The other steps are almost the same, so the explanation is omitted. 18 is a step of reading the energization current of the monitoring electric circuit and averaging each at a predetermined time before and after the control target device or control target circuit is stopped or shut off. 19 obtains the difference between the energization currents of the monitoring circuit input at 18 and calculates the energization current of each control target device or control target circuit. 20 takes the difference between the current setting value and the energization current value calculated in 19, and sets the return current value so that the energization current of the monitoring circuit does not exceed the current setting value even if the control target device or control target circuit recovers To do.
[0024]
By adopting such a configuration, it is possible to calculate the energizing current of each control target device or control target circuit by diverting the energizing current value of the monitoring circuit, and to arrange the energizing current measuring device in each control target device or control target circuit. It is not necessary to take the method to do.
[0025]
【The invention's effect】
In the peak cut controller according to claim 1, the overcurrent flows in the monitoring circuit, and the return current value set when returning the control target device or the control target circuit that is controlled to be “off” is set to the current used by each control target. , And a set current value can be obtained so that the energization current of the monitoring circuit does not exceed the current set value even when the energization current of the control target device or control target circuit is restored.
[0026]
The peak cut controller according to claim 2 provides the method of arranging the energization current measuring device in each control target device or control target circuit by diverting the energization current value of the monitoring circuit in addition to the effect of claim 1. Instead, the current used by each control target device or control target circuit can be calculated.
[Brief description of the drawings]
FIG. 1 is a block diagram of a peak cut controller showing a first embodiment of the present invention.
FIG. 2 is a block diagram of a peak cut controller showing a second embodiment of the present invention.
[Fig. 3] Change in energization current of the monitoring circuit when the control target device or control target circuit is stopped or shut off. [Fig. 4] Flow chart of peak cut controller function. [Fig.

Claims (2)

A current transformer 1 that detects the current flowing through the monitoring circuit, a current measurement circuit 2 that receives the signal from the current transformer 1 and measures the current flowing, and an upper limit of the current flowing through the monitoring circuit (hereinafter referred to as a set current value). When the current setting circuit 3 and the control target device or the control target circuit are in a stopped or shut-off state, the control target device or the control target circuit is restored when the current flowing through the monitoring circuit continues below a certain current value. A return current setting circuit 4 for setting a correct return current, a comparison circuit 5 for comparing the energization current value from the current measurement circuit 2 with the set current value from the current setting circuit 3, and a signal from the comparison circuit 5 A current control circuit 6 that performs “ON” and “OFF” control of the control target device or control target circuit;
In the peak cut controller comprising: control target energization current measuring means 7 for measuring the energization current of the control target device or control target circuit; Even if the return current setting circuit 4 sets the return current so that the energization current of the monitoring circuit does not exceed the set current value,
A peak cut controller characterized by having The control target energization current measuring means 7 includes a control target energization current measurement circuit 10 that calculates an energization current of the control target device or the energization target circuit from a current value at a certain time before and after the operation of the current control circuit. The peak cut controller according to claim 1, wherein:

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