Study on the over-current protection method of the large power inverter with IGCTs

Large power three-level voltage source inverters with IGCTs are widely used in medium and large power drive systems now and have prospective future. Measures should be carefully taken to protect the inverter when over-current occurs due to every reason, especially that due to short circuit in the load or in the inverter itself. The short circuit process of the inverter with IGCTs is analyzed. With software simulation and experiment, the influence of some circuit parameters on the short circuit process is investigated. Then the schematic diagram of the inverter with over-current protection function is designed. System experiments show the inverter has excellent performance.