The design of post arc current measurement system with high precision on multi-break vacuum circuit breakers

A set of post arc current measurement system with high precision on multi-break vacuum circuit breakers(VCBs) was designed, and factors affecting the precision were analyzed. The improved shunt in current measurement showed high accuracy and fast response speed, so it could satisfy the demand of the precision. Meanwhile, with the changing of structure, the problems which were caused by surface action and producing heat were availably solved. In addition, the data acquisition system with optical fiber isolation was used to connect with measurement system. The superiority of post arc current measurement system with high precision in multi-break VCBs was confirmed by simulating in Ansys Maxwell and making experiments. Built simulating model in Ansys Maxwell, and simulated the electric field and thermal field of the shunt. The current measurement system could measure post arc current effectively which was proved. This could provide an effect method to study vacuum arc in Multi-break Vacuum Circuit Breakers.