10kV Power Switching Devices And Solid State Switch

With the development of modern science and technology, the increased productivityalso brings the power quality problems. The increase of various impact and non-linear loadscaused serious pollution to the power supply system, while a variety of precisioninstruments and important industrial loads call for increasingly high demand on powerquality. Especially the voltage sags affect the normal operation of sensitive loads, resultingin huge economic losses. Therefore, improving the quality of power supply problem isimminent.The solid state switch is one kind of equipment based on custom power technology,providing economic and effective plan for improving the power quality and realizinguninterrupted power supply load. So the study on SST has the vital significance.This paper focuses on the study of10kV solid state switch. According to its workingprinciple and operating voltage requirements, the solid-state switch valve structurecomposed of anti-parallel thyristors in series is proposed, but also a series equalizing circuitand various protection circuits. In this paper, the series thyristor trigger synchronizationproblem is analyzed. Considering the cost, voltage levels, isolation and other factors, itadopts the indirect fiber trigger and carriers on the trigger system hardware design,including taking energy circuit, voltage regulator circuit, the optical signal received ortransmitted circuit and the driving circuit design. In addition, in the aspect of the voltagesag detection, a variety of voltage detection methods is discussed, focusing on the waveletanalysis and simulation to compare the advantages and disadvantages of the variousdetection methods. Finally, according to the principle of the power switch operation, twokinds of solid-state switch control strategies is proposed and completes the simulation ofadopting different switching strategies for power switching, different types of short circuitfault on the power supply side and the load side. The simulation results show that thesystem can quickly detect the voltage sags to switch the power supply and be able tocorrectly distinguish the fault location, taking the reliable action.