Research on Circuit Breaker Trip Current Detection and Calibration Technology Based on DSP
Abstract:
In order to verify the overcurrent protection and short-circuit protection functions of the circuit breaker and accurately grasp its working state, a set of circuit breaker calibration device based on DSP and the latest control technology of power electronics is developed. The DSP was used to calculate the test parameters and control the SPWM. The test current was generated by the inverter composed of IGBTs. Through the AC sampling algorithm, the power factor of the load was calculated according to the sampling voltage and current, so that the initial value of the phase angle of the test current waveform can be accurately controlled, which effectively guaranteed the current accuracy of the electromagnetic trip test of the circuit breaker. A special PC operation software and database were designed, which can complete the test parameters setting, test process guidance, voltage and current waveform display and storage, circuit breaker action time display, historical data query and other functions. The real-time acquisition and precise control of the test current waveform are realized, and a reliable detection means is provided for the working reliability of the circuit breaker.
