KR101719561B1 - Controlling apparatus for power regulator - Google Patents

Abstract

The present invention relates to a power regulator control apparatus.
According to the power regulator control apparatus of the present invention, there is provided a power regulator control apparatus comprising: a control board for controlling an operation of a power regulator; a transformer for transforming an AC input voltage supplied to the power regulator and supplying the AC input voltage to the control board; An SCR voltage controller for controlling the magnitude of the AC output voltage of the regulator, a current converter for detecting a current flowing at a lower end of the power regulator and supplying the detected current to the control board, A switch for switching a terminal connected to the transformer according to the AC input voltage and a switch controller for sensing a magnitude of the AC input voltage and controlling a position of the changeover switch in accordance with the sensed AC input voltage, .
As described above, according to the present invention, even if the user does not need to adjust the changeover switch, the voltage input to the control board can be kept constant by automatically switching the primary terminal of the transformer, The reliability of the SCR power controller can be improved. In addition, by detecting the load current and shutting off the AC power with the gate signal interception, it is possible to respond promptly from the point of time when an accidental short circuit occurs.

Description

[0001] CONTROLLING APPARATUS FOR POWER REGULATOR [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power regulator control device, and more particularly, to a power regulator control device that includes a pre-voltage function for maintaining a constant voltage input to a control board without operating a 220V / 440V changeover switch and a function for protecting the power regulator from an over- And a control device.

Preheating to raise the temperature on the weld before welding and post heat to reheat the metal in order to further improve the hardness of the metal after welding is necessary to prevent the rapid rise of the welded portion of the structure. A ceramic case heater composed of a heat wire which generates heat by a current to preheat and postheat to a desired temperature according to the object to be welded, and a power conversion device for controlling the temperature of the heater.

The SCR power regulator controls the phase of the input AC voltage with SCR so that the output voltage can be continuously output from 0 [V] to almost the input voltage level. It is equipment used more than 90% in preheating and post heat treatment of heat treatment (structure, shipbuilding, ocean, nuclear power, chemical, plant).

However, since the input AC voltage is 220 [V] or 440 [V] depending on the industrial work environment, even if the input voltage is changed using the 220V / 440V conversion switch according to the input voltage size, To 16 [V]. If the operator does not adjust the 220V / 440V selection switch according to the input AC voltage, the input voltage of the control board is too low to cause the control board to operate normally, or conversely, the input voltage of the control board doubles, There are many cases of destruction and reliability is degraded.

On the other hand, when the short circuit or short circuit is short, the protective device is insufficient and the base material is broken or the SCR power controller is broken. Current SCR voltage controller for domestic heat treatment is equipped with Earth Leakage Breaker (ELB) to operate safeguard device in case of short circuit or short circuit, but there is a safety problem because the response speed is too slow. In addition, even if an isolation transformer is used, there is a problem that the price and the price increase with volume and weight, and the important advantage of the SCR power controller disappears.

The technology underlying the present invention is disclosed in Japanese Patent Registration No. 10-1429246 (published on Apr. 19, 2014).

SUMMARY OF THE INVENTION The present invention is directed to a power regulator controller including a pre-voltage function for maintaining a constant voltage input to a control board without operating a 220V / 440V changeover switch and a function for protecting the power regulator from an overcurrent .

According to an aspect of the present invention, there is provided a power regulator controller including a control board for controlling operation of a power regulator, a transformer for transforming an AC input voltage supplied to the power regulator and supplying the AC input voltage to the control board, An SCR voltage controller for controlling an AC input voltage to control the magnitude of an AC output voltage of the power regulator, a current converter for detecting a current flowing at a lower end of the power regulator and supplying the current to the control board, A changeover switch for switching a terminal connected to the transformer according to the alternating input voltage, and a switch for detecting the magnitude of the alternating input voltage and for controlling the changeover switch according to the sensed alternating input voltage, A switch controller for controlling the position of It should.

The switch controller includes a rectifier for rectifying the AC input voltage to a DC voltage through a diode rectifier, a distributor for reducing the rectified DC voltage at a constant rate, a detector for detecting a peak value of the distributed voltage, A voltage determination unit for comparing the peak value with a pre-stored reference voltage to determine the magnitude of the AC input voltage, and a controller for controlling the position of the AC input switching switch connected to the transformer according to the determination result.

The control unit may include a first relay driving circuit and a relay.

An overcurrent controller connected to both ends of the current converter for detecting an overcurrent generated at the lower end and for interrupting the gate signal of the control board when the overcurrent is detected and for interrupting the supply of the ac input voltage by operating the earth- .

The overcurrent controller includes a converter for converting the load current detected by the current converter into a voltage value, an overcurrent judging unit for comparing the converted voltage value with a pre-stored set value to determine whether an overcurrent is generated in the load stage, And a blocking unit for blocking the gate signal of the control board and activating the earth leakage breaker to cut off the AC input power when it is determined that an overcurrent has occurred at the lower end.

Wherein the conversion unit comprises: a resistor having a first end connected to the current converter, a second end connected to the current converter and ground, and an input terminal connected to the first end of the resistor, And may include buffers to be connected.

The overcurrent determining unit may include a bi-direction over-current detector having an input terminal connected to an output terminal of the converting unit, a negative direction overcurrent detector having an input terminal connected to the output terminal of the converting unit, and an input terminal connected to the output terminals of the bi- And an AND gate circuit connected to the input terminal of the blocking unit and an output terminal connected to the input terminal of the blocking unit.

The blocking unit includes a D flip-flop having an input terminal coupled to the overcurrent determining unit, a preset circuit coupled to a preset terminal of the D flip-flop, a first output terminal of the D flip- And a second relay driving circuit having an input terminal connected to the second output terminal of the D flip flop and an output terminal connected to the earth leakage breaker, .

As described above, according to the present invention, even if the user does not need to adjust the changeover switch, the voltage input to the control board can be kept constant by automatically switching the primary terminal of the transformer, The reliability of the SCR power controller can be improved. In addition, by detecting the load current and shutting off the AC power with the gate signal interception, it is possible to respond promptly from the point of time when an accidental short circuit occurs.

1 is a configuration diagram of a power regulator control apparatus according to an embodiment of the present invention.
2 is a configuration diagram of a switch controller according to an embodiment of the present invention.
3 is a graph showing output waveforms of respective components of the switch controller according to the embodiment of the present invention.
4A and 4B are graphs showing experimental results when an AC input voltage of 220 V is supplied.
4C and 4D are graphs showing experimental results when an AC input voltage of 440 V is supplied.
5 is a configuration diagram of an overcurrent controller according to an embodiment of the present invention.
6 is a simulation waveform of an overcurrent controller according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

A configuration of a power regulator control apparatus according to an embodiment of the present invention will be described with reference to FIG. 1 is a configuration diagram of a power regulator control apparatus according to an embodiment of the present invention.

First, the power regulator control device includes a control board 100, a transformer 200, an SCR voltage controller 300, a current converter 400, an earth leakage breaker 500, a changeover switch 600 and a switch controller 700 And may further include an overcurrent controller 800.

Specifically, the control board 100 controls the operation of the power regulator. At this time, the control board 100 operates by receiving the AC input voltage transformed from the transformer 200, transmits and receives gate signals or currents from the SCR voltage controller 300 and the current converter 400, and controls the operation of the power regulator do.

Next, the transformer 200 converts the magnitude of the AC input voltage supplied from the input terminal, and supplies the transformed AC input voltage to the control board 100. At this time, the magnitude of the AC input voltage input to the transformer 200 includes at least one of 440 V and 220 V, and the AC input voltage may be converted to 16 V and supplied to the control board 100.

Next, the SCR voltage controller 300 controls the magnitude of the output of the power regulator. At this time, silicon controlled rectifier (SCR) refers to a silicon controlled rectifier and is also referred to as a thyristor.

 Specifically, the SCR voltage controller 300 receives the gate signal from the control board 100 and controls the phase of the AC input voltage to control the voltage supplied to the lower end of the power regulator. As shown in FIG. 1, the SCR voltage controller 300 may be configured by connecting two thyristors in parallel, wherein the two thyristors are connected in parallel with each other, reversing the directions of the cathodes and the anodes. The cathode and the gate of each thyristor are connected to the control board 100.

Next, the current transformer (400, CT, Current Transformer) detects the load current and transfers the detected load current to the control board (100). At this time, the detected load current is used to control the power regulator by determining whether the control board 100 generates an over current or a short circuit current.

Also, the current converter 400 can supply the detected current to the overcurrent controller 800, and the detected current is used to determine whether or not an overcurrent of the lower stage is generated.

Next, the earth leakage breaker 500 cuts off the AC input power at the time of occurrence of the overcurrent and the short-circuit current at the lower end. In addition, the electric leakage circuit breaker 500 controls the electric power supplied to the lower stage by shutting off the AC input power when the power of more than the reference value is supplied to the lower stage.

Next, the changeover switch 600 is connected to the input terminal of the transformer 200 according to the magnitude of the AC input voltage. As shown in FIG. 1, the changeover switch 600 is connected to the 440V terminal of the transformer 200 when the AC input voltage is 440V, and to the 220V terminal of the transformer 200 when the AC input voltage is 220V. The changeover switch 600 may be selected by a user to be connected to the transformer 200.

Next, the switch controller 700 senses the magnitude of the AC input voltage, and then controls the position of the changeover switch 600 according to the sensed AC input voltage. At this time, the switch controller 700 is connected between the input terminal of the power regulator and the changeover switch 600.

Hereinafter, the configuration of the switch controller 700 according to the embodiment of the present invention will be described in detail with reference to FIG. 2 through FIG. 4D. FIG. 2 is a configuration diagram of a switch controller according to an embodiment of the present invention, and FIG. 3 is a graph illustrating output waveforms of respective configurations of a switch controller according to an embodiment of the present invention.

First, the switch controller 700 includes a rectifier 710, a distributor 720, a detector 730, a voltage determiner 740, and a controller 750.

Specifically, the rectifier 710 converts the input AC input voltage into a DC voltage. At this time, the rectifying unit 710 may use a diode rectifying circuit, and the diode rectifying circuit may include at least one of a half-wave rectifying circuit, a full-wave rectifying circuit, and a bridge rectifying circuit.

For example, when rectifying the AC input voltage using the bridge rectifier circuit, a waveform of the type shown in FIG. 3A appears. That is, when the AC input power of 220 V is supplied, the rectifying unit 710 rectifies the AC input power in the form of a radio wave having the maximum value of 311 V, and when the AC input power of 440 V is supplied, The AC input power is rectified in the form of a wave having the maximum value.

Next, the distributing unit 720 reduces the DC voltage received from the rectifying unit 710 at a constant rate. At this time, the distributor 720 can reduce the DC voltage supplied from the rectifier 710 by using a voltage divider, and the voltage divider includes a circuit in which two resistors are connected in series.

For example, assuming that the magnitude of the rectified DC voltage is reduced by a ratio of 1/150 by using a voltage divider, a waveform as shown in FIG. 3B is output. That is, the distribution unit 720 is supplied with a 220V AC input power, and when the AC power is rectified in the form of a 311V radio wave, it appears as a 2.1 V-sized radio wave. When a 440 V AC input power is supplied, Rectify the AC input power.

Next, the detection unit 730 receives the DC voltage reduced in a predetermined ratio from the distribution unit 720, and detects the peak value of the supplied DC voltage. At this time, the detector 730 may use a peak detector including an amplifier, and the peak detector detects and outputs the maximum value of the inputted AC voltage.

For example, when the peak value of the divided voltage is detected using the peak detector, the output voltage appears in the form of (C) in FIG. That is, when the AC input voltage of 220 V is applied and the voltage of the distributor 720 is reduced to 1/150, the detector 730 detects the peak value of 2.1 V as in the waveform of the left waveform of FIG. . When the AC input voltage of 440 V is applied and the voltage divider 720 reduces the voltage by 1/150 times, the detector 730 detects the peak of 4.2 V as shown in the waveform of the right waveform of FIG. Value.

Next, the voltage determination unit 740 determines the magnitude of the AC input voltage. Specifically, the voltage determining unit 740 compares the peak value received from the detecting unit 730 with the pre-stored reference voltage to determine the magnitude of the AC input voltage, and transmits the determination result to the controller 750. At this time, the voltage determination unit 740 can determine the magnitude of the AC input voltage using the comparator circuit.

For example, assume that a comparator with a reference voltage of 3V and an output voltage of 0V and 5V is used to determine the magnitude of the ac input voltage. At this time, if the detected peak value is 2.1V, the peak value is lower than 3V, which is the reference voltage, so that the voltage determination unit 740 outputs 0V as the left waveform shown in (D) of FIG. Conversely, if the detected peak value is 4.2V, the peak value is higher than 3V, which is the reference voltage, so that the voltage determination unit 740 outputs 5V as shown in the right waveform shown in FIG. Then, the voltage determination unit 740 determines that the AC input voltage is 220V when the output of the comparator is 0V, and determines that the AC input voltage is 440V when the output is 5V.

Next, the control unit 750 controls the position of the changeover switch 600 according to the determination result of the voltage determination unit 740. [ At this time, the control unit 750 can use the relay driving circuit and the relay, and the relay driving circuit operates the relay according to the determination result of the voltage determination unit 740.

For example, assuming that the position of the changeover switch 600 is controlled by using a relay and a relay drive circuit, when the AC input voltage is determined to be 220 V, the controller 750 drives the relay, . Conversely, when the AC input voltage is determined to be 440 V, the control unit 750 drives the relay to place the switch at the 440 V terminal of the transformer 200.

FIGS. 4A and 4B are graphs showing experimental results when an AC input voltage of 220 V is supplied, and FIGS. 4C and 4D are graphs showing experimental results when an AC input voltage of 440 V is supplied.

First, as shown in FIG. 4A, the output waveform of the distribution unit 720 is slightly different from that of the positive half period and the negative half period voltage, but the detection unit 730 Is maintained at about 2V which is the maximum value of the output waveform of the distributor 720. [ As shown in FIG. 4B, since the output of the detecting unit 730 is about 2V and is lower than the reference voltage of 3V, the voltage determining unit 740 outputs 5V.

As shown in FIG. 4C, the output waveform of the distributor 720 has a positive half period and a negative half period voltage magnitude which are almost equal to each other, The output of the comparator 730 is maintained at about 4V which is the peak value of the voltage divider output waveform. As shown in FIG. 4D, since the output of the detector 730 is about 4V, which is higher than the reference voltage of 3V, the voltage determining unit 740 outputs 0V.

The overcurrent controller 800 is connected to the current transformer 400, the SCR voltage controller 300, the control board 100 and the earth leakage breaker 500. The overcurrent controller 800 detects the overcurrent generated at the lower stage, The gate signal of the control board 100 is cut off and the earth leakage breaker 500 is operated.

Hereinafter, a configuration of an overcurrent controller 800 according to an embodiment of the present invention will be described with reference to FIG. 5 is a configuration diagram of an overcurrent controller according to an embodiment of the present invention.

First, the overcurrent controller 800 includes a conversion unit 810, an overcurrent determination unit 820, and a cutoff unit 830.

Specifically, the converting unit 810 converts the detected load current through the current converter 400 into a voltage. According to an embodiment of the present invention, the converting unit 810 includes a resistor whose first end is connected to the current transformer 400 and whose second end is connected to the current transformer 400 and the ground, And a buffer connected to an input terminal of the overcurrent judging unit 820. The converting unit 810 converts the detected current through the current transformer 400 into a voltage through a resistor, And supplies the voltage output through the buffer to the overcurrent judging unit 820. [0053]

Next, the overcurrent determining unit 820 compares the pre-stored set value with the magnitude of the load current to determine whether an overcurrent flows at the load end, and transmits the determination result to the shutting unit 830. Specifically, the overcurrent determining unit 820 compares the load current in the positive (+) direction and the load current in the negative (-) direction with pre-stored set values. If at least one of the load currents in the both directions and the load current in the negative direction is greater than the previously stored set value, it is determined that an overcurrent occurs in the lower part of the load.

According to an embodiment of the present invention, the overcurrent determining unit 820 includes a bi-directional overcurrent detector having an input terminal connected to the output terminal of the transforming unit 810, a negative direction overcurrent detector having an input terminal connected to the output terminal of the converting unit 810, And an AND gate circuit having an input terminal connected to the output terminals of the bi-directional overcurrent detector and the negative direction overcurrent detector and an output terminal connected to the input terminal of the blocking portion 830.

Here, the bi-directional overcurrent detector compares the pre-stored set value with the load current when the load current is bi-directional, and the negative over-current detector compares the pre-stored set point and the load current when the load current is negative. For example, if the limit output voltage of the overcurrent detector is 5V, the comparator outputs a voltage of 0V when the load current is higher than the preset value, and a voltage of 5V when the load current is lower.

Then, the outputs of the respective detectors are input to the AND gate circuit, and when at least one of the outputs of the detectors is 0 [V], the output of the AND gate becomes a 0 state, that is, 0 [V]. When the output of each detector is 5 [V], the output of the AND gate becomes '1', that is, 5 [V].

Next, the blocking unit 830 cuts off the AC input power when it is determined that an overcurrent occurs at the lower end. Specifically, when it is determined that an overcurrent has occurred at the lower end, the blocking unit 830 blocks the gate signal transmitted from the control board 100 to prevent the signal from being transmitted to the SCR voltage controller 300, (500) to cut off the supply of the AC input voltage.

On the other hand, when it is determined that the overcurrent does not occur at the lower end, the blocking unit 830 transmits the gate signal to the SCR voltage controller 300 without interrupting the gate signal transmitted from the control board 100, ) Is not operated but the AC input voltage is supplied.

According to an embodiment of the present invention, the blocking unit 830 includes a D flip-flop (D flip-flop) to which an input terminal is connected to the overcurrent determining unit 820, a preset circuit connected to a preset terminal of the D flip- A gate signal interrupting circuit having an input terminal connected to the gate terminal of the control board and an output terminal connected to the SCR voltage controller 300, an input terminal connected to the second output terminal of the D flip- And a relay driving circuit connected to the output terminal.

Here, the D flip-flop receives the output of the overcurrent judging unit 820, and the output of the overcurrent judging unit 820 becomes '0' when an overcurrent occurs and becomes '1' when an overcurrent does not occur. For example, assuming that the limit output voltage is 5V, 0 [V] is output in the '0' state and 5 [V] is output in the '1' state.

The gate signal cutoff circuit may be configured as an AND gate circuit and receives the gate signal of the control board and the output signal of the D flip-flop to determine whether to block the gate signal. That is, when at least one of the gate signal of the control board 100 and the output of the D flip-flop is '0', the gate signal cutoff circuit transmits '0' to the SCR voltage controller 300 as an output, .

Then, the relay driving circuit controls the earth leakage breaker 500 using the output signal of the D flip-flop and the relay, and the preset circuit initializes the over-current state and the '0' state of the D flip-flop.

Hereinafter, a simulation result of the overcurrent controller 800 according to the embodiment of the present invention will be described with reference to FIG. 6 is a simulation waveform of an overcurrent controller according to an embodiment of the present invention.

As shown in FIG. 6, at about 0.035 second, an overcurrent is generated at a load current in both directions higher than the pre-stored set value, and the gate signal is cut off. In order to reset the overcurrent state to the steady state at 0.08 second, the preset circuit generates the initialization signal in order to initialize the output of the D flip-flop, and it can be seen that the shutoff gate signal is normally output.

According to the embodiment of the present invention, even if the user does not adjust the changeover switch, the voltage input to the control board can be kept constant by automatically switching the transformer primary terminal, The reliability of the SCR power controller can be improved by eliminating the cause of the destruction. In addition, by detecting the load current and shutting off the AC power with the gate signal interception, it is possible to respond promptly from the point of time when an accidental short circuit occurs.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100: control board 200: transformer
300: SCR voltage controller 400: current converter
500: Earth leakage breaker 600: Changeover switch
700: Switch controller 710: Rectifier
720: distribution part 730: detection part
740: voltage determination unit 750:
800: overcurrent controller 810:
820: Overcurrent judging unit 830:

Claims (8)

A control board for controlling operation of the power regulator,
A transformer for transforming an AC input voltage supplied to the power regulator and supplying the transformed voltage to the control board,
An SCR voltage controller for controlling the magnitude of the AC output voltage of the power regulator by controlling the AC input voltage,
A current converter for detecting a current flowing at a lower end of the power regulator and supplying the detected current to the control board,
An earth leakage breaker for interrupting the AC input voltage when an overcurrent is generated at the lower end,
A changeover switch for switching a terminal connected to the transformer according to the AC input voltage,
A switch controller sensing the magnitude of the AC input voltage and controlling the position of the changeover switch in accordance with the sensed AC input voltage,
An overcurrent controller connected to both ends of the current converter for detecting an overcurrent generated at the lower end and for interrupting the gate signal of the control board when the overcurrent is detected and for interrupting the supply of the ac input voltage by operating the earth- ≪ / RTI &
The switch controller includes:
A rectifying unit for rectifying the AC input voltage to a DC voltage through a diode rectifier,
A distribution unit for reducing the rectified DC voltage at a constant rate,
A detector for detecting a peak value of the divided voltage,
A voltage determination unit for comparing the detected peak value with a pre-stored reference voltage to determine the magnitude of the AC input voltage, and
And a controller for controlling the position of the AC input switch connected to the transformer according to the determination result,
The overcurrent controller includes:
A converter for converting the load current detected by the current converter into a voltage value,
An overcurrent judging unit for comparing the converted voltage value with a pre-stored set value to judge whether an overcurrent is generated in the lower stage, and
And a shutoff unit for shutting off the gate signal of the control board and activating the earth leakage breaker to cut off the AC input power when it is determined that an overcurrent has occurred at the lower end. delete The method according to claim 1,
Wherein,
A first relay driving circuit and a relay. delete delete The method according to claim 1,
Wherein,
A resistor having a first end connected to the current transformer and a second end connected to the current transformer and ground,
And a buffer having an input terminal connected to a first end of the resistor and an output terminal connected to an input terminal of the overcurrent judging unit, The method according to claim 1,
The overcurrent judging unit judges,
A bi-directional overcurrent detector to which an input terminal is connected to an output terminal of the converting unit,
A negative direction overcurrent detector to which an input terminal is connected to an output terminal of the conversion unit, and
And an AND gate circuit having an input terminal connected to the output terminals of the bi-direction over-current detector and the negative direction over-current detector, and an output terminal connected to the input terminal of the blocking portion. The method according to claim 1,
The cut-
A D flip-flop having an input terminal connected to the overcurrent judging unit,
A preset circuit connected to a preset terminal of the D flip-flop,
A gate signal blocking circuit having an input terminal connected to the first output terminal of the D flip flop and a gate signal terminal of the control board and an output terminal connected to the SCR voltage controller,
And a second relay driving circuit having an input terminal connected to a second output terminal of the D flip-flop, and an output terminal connected to the earth leakage breaker.

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