Design On Phase-controlled System Of Fiber-controlled Module Vacuum Circuit Breaker

Vacuum circuit breaker uses vacuum as the insulation and extinguishing arc medium, which has many advantages, such as high reliability, no explosion danger, small volume, light weight, long life, no harm to the environment and simple maintenance. Therefore, it has been using widely since applied in electrical power system. But long vacuum gap has saturating effect and is hard to make, so it only widely used in the field of voltage level below110 kV. In order to apply vacuum circuit breaker in higher voltage level field, we tried to series up several breakers. Multi-breaker vacuum circuit breaker made use of the excellent medium recovery characteristics of short vacuum gap to achieve higher withstand voltage level. Firstly, the paper introduced the structure of fiber-controlled module vacuum circuit breaker.Phase-controlled circuit breaker open or close at expected phase of voltage and current to eliminate the electromagnetic effects of inrush current and over-voltage which arouse by switching process in order to enhance the breaking capacity of circuit breaker. Firstly, the paper analyzed the effective methods that raise the reliability of circuit breaker, secondly, introduced the advantages and study meanings of phase-controlled technology, and then introduced the principles and open/close processes of phase-controlled circuit breaker, all of which provided the theoretical basis for designing the phase-controlled system.Phase-controlled system of fiber-controlled module vacuum circuit breaker consists of module controller and phase controller. The two controllers communicate by fiber, which eliminates the transmission distortion caused by electromagnetic interference essentially. The module controller takes Mega16 as core processor with assembling displacement, voltage and temperature sensors. The module controller not only sends status messages to the phase controller, but also receives the open/close command from it. The phase controller takes TMS320LF2407A as core processor that realizes the functions of adjusting signal, forecasting best phase and giving open/close command.The experiment results show that the accuracy of phase-control system within lms meets the designing command. The EMC tests show that the module controller installed in electrical power system has good reliability and capacity of resisting disturbance.