The current era is an era of rapid economic development, and various technologies have emerged as the times require. Although my country's high-voltage electrical equipment is becoming more and more perfect, because in actual work, high-voltage electrical equipment will generate a large amount of current during work. Therefore, may be affected by the external environment

There will be inevitable failures. Therefore, it is necessary for technicians to apply automatic control and electrical debugging technology to high-voltage electrical equipment under reasonable circumstances, so as to promote the normal operation of high-voltage electrical equipment.

1. The principle of direct start control. The principle of direct start-up control of high-voltage motor is mainly manifested in the combination of direct start-up of vacuum contactor and comprehensive protection controller. The high-voltage motor generates current in use and leakage state, and enters comprehensive protection control through zero-sequence electric TA and electric TA sampling circuit The integrated circuit protector can detect and analyze the running state of the motor. If there is a fault such as leakage or lack of equality, the action of the vacuum connector of the actuator will cut off the running power of the motor and upload the fault. At the same time, an audible and visual alarm is displayed. When the fault is not eliminated, lock the program of the comprehensive protection controller so that it cannot enter the normal working state.

2. The control principle of frequency conversion start. In the past, the voltage structure used for variable frequency start of high-voltage motors was high-low-high, or a three-level superposition structure. Based on GBT high-power insulated gate bipolar tubes, the high-voltage inverter directly connected the power supply of the high-voltage motor. manipulation. At this stage, the high-power and high-voltage grade GBT insulating bipolar transistor switching tube has been successfully developed, the current structure is replaced by the AC-DC core transformer structure, and the three-phase high-voltage alternating current is rectified into a high-voltage through a high-current high-voltage rectifier diode. The direct current is triggered by the fast insulating bipolar high-voltage switch tube GBT to generate a three-phase AC high-voltage pulse power supply, which is a variable frequency power supply. The reactor is filtered to become a three-phase sine wave alternating current (he variable frequency), which is supplied to the daily operation of the high-voltage alternating current motor.

   The computer control center in the frequency conversion controls the opening and closing of the fast insulated gate bipolar high-voltage switch tube IGBT. Through the internal program of the computer and the peripheral electronic circuit, the high-voltage alternating current frequency and voltage amplitude are controlled, and the high-voltage alternating current motor can be Realize soft start, speed regulation and soft stop. The controllable range of voltage output frequency is 0-400H. When the high-voltage AC motor enters the soft stop state, the internal program of the computer controls and triggers the pulses that are turned on, so that the high-voltage filter capacitor discharges current, controls the GBT, and releases the stored electricity. When the discharge is completed, the high-voltage indicator light goes out to prevent the circuit from causing an accident.