Research And Realization Of Permanent Magnetic Vacuum Circuit Breaker Synchronous Control Technology

In this paper, aiming at the inrush current and over-voltage of the vacuum circuit breaker in closing and opening processes, which can impact the power system seriously, in order to shorten the transient process and to reduce the damage caused by the switch on-off, studying the synchronous control technology of bi-stable permanent magnetic vacuum circuit breaker.Firstly, studying principal of the bi-stable permanent magnetic actuator, determine the magnetic field and force change, and then, analysis the principal and difficult problem to realize synchronous control technology. In this paper, through build the simulation model, analysis the different load including capacitor, no-load line, no-load transformer and closing the load in different phase. Completing the synchronous controller’s hardware and software design. The hardware design of this controller contains the core of LPC2292, signal sampling and conditioning circuit, main control circuit, coil driving and self checking circuit, temperature measure circuit, communication interface circuit and so on. The design of software includes the transplantation of μC/OS-11on LPC2292, resource allocation, preparation of driver, synchronous control of closing and opening, state checking, data communication, LCD display. Finally, to the key technology of zero extraction, design FIR filter, which can elimination the noise effectively, using linear interpolation method to extract the zero moment. Analysis the factors containing control voltage, ambient temperature, pre-strike, aging and wear effecting closing and opening time, due to the complexity of the influencing factors, can’t calculation the closing and opening time using accurate mathematical model, so use artificial intelligence theory to design BP neural network to predict the closing and opening time, choose L-M algorithm to train the data achieved, can control the error below0.2ms, and achieve a great fitting result. Finally, debugging the controller, from the output waveform, can achieve the goal of zero point capture and synchronous control.