Research On Dual Power Switching Strategy Based On SSTS And DVR Coordinated Control

With the rapid development of industrial technology,the important load represented by petrochemical and iron and steel enterprises has put forwardhigher requirements for power supply reliability.At present,two power supply modes are mainly used to ensure the uninterrupted power supply of this kind of load.Therefore,the automatic switching device of power supply has been widely used,including the preparation of self switching device and the fast cutting device.The quick cut device is developed on the basis of the self throw device,and its performance is better than that of the automatic switching device.However,the starting signal of the fast cut device is the external signal,and the start-up time is restricted by the outside,which may not start at the first time after the main power failure.In addition,the switching time of the fast cutting device is affected by the phase difference between the residual voltage and the voltage of the standby power supply,and the switching time is too long when the phase difference is large,and it can not meet the demand for the rapid recovery of the important load.In order to meet the power supply requirements of important load,the shortcomings of the power automatic switching device are studied.The main contents are summarized as follows:First,the solid-state switch is used to replace the traditional mechanical switch to shorten the switching time of the power supply.The zero crossing switching simulation model of solid state transfer switch is built in Simulink,and RLC series is used as an example to simulate.The results show that the switching time under zero crossing switching mode is within 10 ms,and the switching time is much less than that of traditional mechanical switches.The related literature shows that when the load side induction motor is switched on,the switching power will produce a large impact current,resulting in the failure of the relay protection device resulting in the power failure of the important load.On this basis,dynamic voltage restorer is added to compensate the switching point voltage and suppress the impact current during the switching process.Simulation results show that the proposed method can achieve fast switching and suppress impulse current effectively.At the end of this paper,the simulation experiment platform is built,and the circuit of each part of the system is designed under the existing condition of the laboratory.The single phase experimental prototype is built,and the DSP2812 programming is completed.The reliability of the coordinated control to guarantee the important load and the non interruption power supply is verified.