Debugging method and device for magnetic valve type controllable shunt reactor

Abstract

The invention relates to a debugging method and device for a magnetic valve type controllable shunt reactor, and belongs to the technical field of power systems. According to the method, the trigger pulse frequency during normal operation of the magnetic valve type controllable shunt reactor is adjusted, and the number of trigger pulses is reduced under the condition that the trigger angle of the thyristor is not changed, so that the trigger pulses subjected to frequency reduction can reduce the magnitude of direct-current exciting current in the magnetic valve type controllable shunt reactor, and the frequency of the direct-current exciting current in the magnetic valve type controllable shunt reactor is reduced. And the change trend of the magnitude of the three-phase current can be accurately reflected. According to the method, the trigger pulse in normal operation is subjected to frequency division processing, so that the problem that the phase of the reactor is incorrect when the reactor is electrified and debugged for the first time can be effectively solved, tripping or damage of the reactor caused by the phase can be avoided, field installation and debugging personnel are helped to carry out troubleshooting, and the debugging efficiency of the magnetic valve type controllable shunt reactor complete equipment is improved.

Description

Technical Field

[0001] The invention relates to a debugging method and a device for a magnetic valve type controllable shunt reactor, belonging to the technical field of power systems. Background Art

[0002] The magnetically controlled reactor uses DC excitation to saturate the core. Due to the existence of the core magnetic valve structure, the increase in DC excitation will not cause the entire core to enter a saturated state, thereby achieving smooth regulation of the reactance value. At present, magnetically controlled reactors are widely used in reactive power compensation in power systems. They can dynamically adjust according to the reactive power required in the system, improve power utilization, and increase system power factor.

[0003] The magnetically controlled reactors currently used in practical applications are three-phase, and each phase is controlled separately. When powered on for the first time, due to the large number of links involved in the wiring of the power distribution system, abnormal phase problems may sometimes be encountered. These problems are mainly caused by negative phase sequence, inconsistency between the controller phase sequence and the reactor phase sequence, and incorrect reactor wiring. At this time, the controller will not be able to correctly trigger the reactor of the corresponding phase when calculating the trigger angle of each phase, which will cause the reactor current to be large or the three-phase imbalance to occur, and may even cause tripping in severe cases. Summary of the invention

[0004] The object of the present invention is to provide a debugging method and device for a magnetic valve type controllable shunt reactor, so as to solve the problem of tripping caused by three-phase imbalance existing in the first power-on process.

[0005] In order to solve the above technical problems, the present invention provides a debugging method for a magnetic valve type controllable shunt reactor, and the debugging method comprises the following steps:

[0006] When the magnetic valve type controllable shunt reactor is powered on and debugged for the first time, the trigger pulse during normal operation of the reactor is used as a reference. The trigger pulse is frequency-reduced according to the set ratio without changing the pulse trigger angle. The adjusted trigger pulse is used to generate a PWM wave to control the thyristor to debug the magnetically controlled reactor.

[0007] The present invention adjusts the trigger pulse frequency of the magnetic valve type controllable shunt reactor during normal operation, reduces the number of trigger pulses without changing the thyristor trigger angle, so that the trigger pulse after frequency reduction can not only reduce the magnitude of the DC excitation current in the magnetic valve type controllable shunt reactor, but also accurately reflect the change trend of the three-phase current magnitude. The present invention divides the trigger pulse frequency during normal operation, which can effectively solve the problem of incorrect phase when the magnetic control reactor is powered on for the first time, avoids the tripping or damage of the reactor, helps on-site installation and commissioning personnel to conduct fault detection, and improves the commissioning efficiency of the complete set of magnetic control reactors.

[0008] Furthermore, the setting ratio is set according to the current required by the magnetic valve type controllable shunt reactor. The smaller the setting ratio, the smaller the current.

[0009] A debugging device for a magnetic valve type controllable shunt reactor comprises a frequency division coefficient register, a duty cycle register, a counter and a data comparator. The frequency division coefficient register, the counter and the data comparator are used to generate a trigger pulse when the magnetic valve type controllable shunt reactor is in normal operation. The duty cycle register is used to adjust the trigger angle of the generated trigger pulse of the magnetic valve type controllable shunt reactor. The frequency division coefficient register is also used to reduce the frequency of the trigger pulse according to a set ratio based on the trigger pulse when the reactor is in normal operation without changing the pulse trigger angle when the magnetic valve type controllable shunt reactor is powered on for the first time for debugging. The adjusted trigger pulse is used to generate a PWM wave to control a thyristor to debug the magnetic valve type controllable shunt reactor.

[0010] The present invention adjusts the trigger pulse frequency of the magnetic valve type controllable shunt reactor during normal operation, reduces the number of trigger pulses without changing the thyristor trigger angle, so that the trigger pulse after frequency reduction can not only reduce the magnitude of the DC excitation current in the magnetic valve type controllable shunt reactor, but also accurately reflect the change trend of the three-phase current magnitude. The present invention divides the trigger pulse frequency during normal operation, which can effectively solve the problem of incorrect phase when the magnetic control reactor is powered on for the first time, avoids the tripping or damage of the reactor, helps on-site installation and commissioning personnel to conduct fault detection, and improves the commissioning efficiency of the complete set of magnetic control reactors.

[0011] Furthermore, the frequency division coefficient register uses the clock as a reference and performs frequency reduction processing on the trigger pulse according to a set ratio.

[0012] Furthermore, the setting ratio is set according to the current required by the magnetic valve type controllable shunt reactor. The smaller the setting ratio, the smaller the current.

[0013] Based on the clock and adjusted according to the set ratio, it can accurately reflect the changing trend of the three-phase current and reduce the problems caused by phase sequence imbalance. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a principle diagram of the frequency division control triggering thyristor of the magnetic valve type controllable shunt reactor of the present invention. DETAILED DESCRIPTION

[0015] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0016] Embodiment of the debugging device of magnetically controlled reactor

[0017] The reactance value of the magnetic valve controllable shunt reactor at the first power-on is adjusted by the DC excitation current in its control circuit, which is determined by the special structure of the magnetic valve controllable shunt reactor itself. When the DC excitation current is 0, the magnetic valve controllable shunt reactor can be regarded as an equivalent no-load transformer, and the equivalent impedance of the working winding is very large. As the DC excitation current of the magnetic valve controllable shunt reactor gradually increases, the smooth output of reactive capacity is achieved. When the rated reactive capacity is reached, the current flowing through the reactor reaches the rated output. In the normally operated equipment, the DC excitation size in each phase control circuit changes with the load in the line. If the phase sequence is wrong, the DC excitation current will not be able to correctly adjust the reactance value in each phase line, resulting in unbalanced load of the three-phase reactor line, unbalanced three-phase voltage, and excessive current in a certain phase reactor.

[0018] Therefore, when powered on for the first time, the DC excitation current value can be reduced to avoid a large change in the reactance value of the magnetic valve controllable shunt reactor. At this time, even if there is an abnormal phase sequence problem, the equivalent impedance of the reactance value working winding is large, which will not cause excessive current in the reactor and three-phase imbalance in the line. The size of the DC excitation current in the reactor is determined by the trigger angle of the two thyristors in the magnetic control box. In essence, it is a unidirectional full-wave rectifier circuit composed of two thyristors. In order not to change the thyristor trigger angle under normal circumstances, the DC excitation current is reduced by frequency reduction, that is, frequency division control.

[0019] The present invention includes a frequency division coefficient register, a duty cycle register, a counter and a data comparator. The frequency division coefficient register, the counter and the data comparator are used to generate a trigger pulse when the magnetically controlled reactor is in normal operation. The duty cycle register is used to adjust the trigger angle of the generated trigger pulse when the magnetically controlled reactor is in normal operation. The frequency division coefficient register is used to reduce the frequency of the trigger pulse according to a set ratio when the magnetic valve type controllable parallel reactor is powered on for the first time without changing the pulse trigger angle, based on the trigger pulse when the reactor is in normal operation. The adjusted trigger pulse is used to generate a PWM wave to control the thyristor to debug the magnetically controlled reactor. The implementation principle of the device is as follows: Figure 1 As shown, the following is explained with reference to specific examples.

[0020] Frequency division control refers to the use of the frequency division coefficient register to generate trigger pulses of different frequencies while keeping the trigger angle unchanged. During the first power-on debugging, the frequency division coefficient register is used to set the proportional coefficient to reduce the number of trigger pulses. Compared with the normal trigger pulse, the trigger pulse after frequency division can effectively reduce the DC excitation size but does not change its change trend. In this way, even if the phase sequence is wrong, the current flowing through the maximum current phase in the magnetically controlled reactor will not be too high to cause damage or tripping due to three-phase imbalance. The use of the trigger pulse after frequency division can accurately reflect the change trend of the three-phase current size. After the first power-on debugging is completed, the normal operation of the magnetic valve type controllable shunt reactor can be realized by simply changing the proportional coefficient to the normal number of pulse outputs.

[0021] When the device is powered on for the first time for debugging, the trigger pulse of the magnetic valve type controllable shunt reactor during normal operation is used as a reference, and the trigger pulse is down-converted according to the set ratio using the clock frequency division register, and the adjusted trigger pulse is used to generate a PWM wave to control the thyristor to debug the magnetic valve type controllable shunt reactor. The set ratio is set according to the current required by the magnetic valve type controllable shunt reactor. The smaller the set ratio, the smaller the current. This embodiment adds a set value to distinguish different divided pulses. It is set to 0 under normal circumstances, and the controller outputs a normal number of trigger pulses. When debugging, the set value can be greater than 1, for example, when it is 2, the controller outputs 1 / 3 of the number of trigger pulses. The on-site commissioning personnel set the frequency division ratio constant during the first power-on commissioning. Smaller changes in the DC excitation current can correctly reflect the trend of the three-phase current size of the reactor, and will not cause tripping and other problems under abnormal phase conditions, making it convenient for personnel to troubleshoot. After debugging is correct, the frequency division constant is changed to the normal operating parameters, and the magnetic valve controllable shunt reactor can be used normally, greatly improving the commissioning efficiency of the complete set of magnetic valve controllable shunt reactors.

[0022] Embodiment of the debugging method of magnetic valve type controllable shunt reactor

[0023] When the magnetic valve type controllable shunt reactor is powered on for the first time for debugging, the present invention uses the trigger pulse of the magnetic valve type controllable shunt reactor during normal operation as a reference, and performs frequency reduction processing on the trigger pulse according to a set ratio without changing the pulse trigger angle, and uses the pulse after frequency reduction to trigger the thyristor to debug the magnetic valve type controllable shunt reactor. The specific implementation of the debugging method has been described in detail in the embodiment of the debugging device of the magnetic control reactor, and will not be repeated here.

Claims

1. A method for debugging a magnetic valve type controllable shunt reactor, characterized in that: The method comprises the following steps: When the magnetic valve type controllable shunt reactor is powered on and debugged for the first time, the trigger pulse during normal operation of the reactor is used as a reference. The trigger pulse is frequency-reduced according to the set ratio without changing the pulse trigger angle. The adjusted trigger pulse is used to generate a PWM wave to control the thyristor to debug the magnetically controlled reactor.

2. The debugging method of the magnetic valve type controllable shunt reactor according to claim 1 is characterized in that: The setting ratio is set according to the current required by the magnetic valve type controllable shunt reactor. The smaller the setting ratio, the smaller the current.

3. A debugging device for a magnetic valve type controllable shunt reactor, comprising a frequency division coefficient register, a duty cycle register, a counter and a data comparator, wherein the frequency division coefficient register, the counter and the data comparator are used to generate a trigger pulse when the magnetic control reactor is in normal operation, and the duty cycle register is used to adjust the trigger angle of the generated trigger pulse of the magnetic control reactor, characterized in that: The frequency division coefficient register is also used when the magnetic valve type controllable shunt reactor is powered on for the first time for debugging. Under the premise of not changing the pulse trigger angle, the trigger pulse during normal operation of the reactor is used as a reference, the trigger pulse is frequency-reduced according to the set ratio, and the adjusted trigger pulse is used to generate a PWM wave to control the thyristor to debug the magnetically controlled reactor.

4. The debugging device of the magnetic valve type controllable shunt reactor according to claim 3 is characterized in that: The frequency division coefficient register uses the clock as a reference and performs frequency reduction processing on the trigger pulse according to a set ratio.

5. The debugging device of the magnetic valve type controllable shunt reactor according to claim 3 is characterized in that: The setting ratio is set according to the current required by the magnetic valve type controllable shunt reactor. The smaller the setting ratio, the smaller the current.

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