混合式高压直流断路器分断过程电磁瞬态建模和测试

HVDC circuit breaker is the core equipment of the DC grid. It is required to cut off large currents of tens to thousands of amperes within a few milliseconds. The strong electromagnetic disturbance during the breaking process may cause interference, which will in return influence IGBTs and the proper work of the secondary equipment. Due to the lack of standards for electromagnetic driver tests, the theoretical analysis and testing are combined to analyze the electromagnetic transient process. After that, a test is firstly carried out in the laboratory to verify the actual collector emitter (V_CE) and gate drive (V_GE) in a 500kV hybrid DC circuit breaker with a maximum breaking current of 25kA, and the tests signals were further analyzed in both time and frequency domains to extract accurate interference characteristics. The results indicate that the interference characteristics of V_CE/V_GE during the breaking process is similar to the surge test and damped oscillation wave, while the power interference characteristics are closer to the damped oscillation waves. Therefore, these two kinds of anti-electromagnetic interference capabilities should be considered in design and test.