Design And Verification Of IGCT Gate Drive State And Parameter Detection Circuit

Integrated Gate Commutated Thyristor(IGCT)with advantages of low loss,high reliability,high current-carrying capability,and versatile application scenarios,has been widely used.However,during practical operation,faults such as overvoltage and overcurrent may occur,which can result in damage to the IGCT or even the complete failure of the power system.Therefore,it is necessary to detect the voltage and current in the operating state of the IGCT using a gate drive unit in order to identify faults and take timely actions.In this thesis,the gate driver state,voltage,and current parameter detection circuit of the IGCT are investigated through simulations and experiments.The main research contents are as follows,Firstly,the IGCT detection scheme is determined.Analyzing the composition and operation principle of the IGCT gate driver,as well as the principle of gate driver state detection based on voltage and current parameters,the overall detection scheme of the IGCT is determined.Secondly,Design and verification of the IGCT gate driver state detection circuit.The driver state signal and internal/external voltage detection circuits are designed.Circuit simulations and analyses are conducted by PSpice and Multisim.The voltage detection circuit board and voltage controller are designed and implemented by Altium Designer 21.Voltage isolation protection is achieved using diode clamping.Experimental results show that the designed voltage detection circuit can measure the gate-cathode voltage,driver supply voltage,turn-off capacitor charging voltage,and IGCT anode voltage of a 4.5 kV reverse blocking IGCT driver.A voltage acquisition scheme based on FPGA+AD7606 is designed,and voltage signals are displayed based on ADC.Finally,Design and verification of the IGCT current parameter detection circuit.Based on the requirements of detecting the gate turn-off pulse current of the IGCT,the technical specifications are determined.A physical PCB Rogowski coil is designed,and the electrical parameters of the PCB Rogowski coil are obtained by COMSOL and a vector signal analyzer.Active integration circuits are simulated and analyzed in PSpice,and the OPA2333 is chosen as the integration chip.An integration circuit board is designed,and experimental tests are conducted to determine the scaling factor of the PCB Rogowski coil.The current parameter detection circuits for both the PCB Rogowski coil and the commercial Rogowski coil are tested.The results show that the designed PCB Rogowski coil can achieve performance comparable to the commercial Rogowski coil,meeting the technical requirements.The research findings provide valuable references for the detection of IGCT driver circuits.