Study Of The Technologies Of Synchronization Control On The Switching Capacitors While Realize VAR Compensation

Today it usually use shut capacitor to carry on the compensation of reactive power in power-supply network, and in the compensation process switching capacitors is unavoidable. The traditional way of switching capacitor is usually random, which is easy to produce inrush current and overvoltage. Lead high current and overvoltage will damage the switch and electrical equipments. Comparing with traditional method, adopting synchronization-switching technique to switch capacitor can effectively inhibit the inrush current and overvoltage that caused by switching capacitor. The development of micro-technology, power electrics technology, permanent magnet material, especially the invention of Permanent Magnet Actuator (PMA) provides advantageous conditions to implementation of the synchronization-switching technique. By far, the studies and applications about PMA are virtually forced on the vacuum circuit breaker of medium and high voltage services. However, less work has been done on low voltage permanent magnetic contactor. Consequently, this paper taking low voltage permanent magnetic contactor as the research objects, make in-depth research on the key technology of using permanent magnetic contactor to synchronous switch capacitor.Firstly, the finite element software ANSYS was used to create the model of PMA. And the working principle of PMA has been analyzed from the point of electromagnet. Then, the switching capacitor model was simulated by Matlab/Simulink. The result of simulation shows that using adopting synchronization-switching technique to switch capacitor to inhibit the inrush current and overvoltage is practicable. The synchronization control strategy of permanent magnetic contactor was provided on above foundation.Secondly, taking permanent magnetic contactor HFE12-C for example, the main factors influencing the contactor's actuating time were analyzed. There include control voltage, environmental temperature and so on. To the above influencing factors, the experimental research of HFE12-C has been carried out to survey the contactor actuating time that in different control voltage and environmental temperature. The test result provides the data of building the contactor time predictable model.Finally, for the non-linearity mapping relation among control voltage, environmental temperature and contactor actuating time, BP Neural Networks were proposed to forecast the contactor actuating time. The BP Neural Network model with LM Algorithm was established. This article takes the HFE12-C actuating time as the primary data sample to train the network and get the threshold and weights. Then, test samples were used to inspect the Network. The experimental results indicate that the BP Neural Networks designed in this paper is efficacious. Predicted error about the training samples is in the range of ±0.1ms. Meanwhile the max of predicted error about the testing samples is 0.12ms. The results made a base for materializing synchronization control of the permanent magnetic contactor.