Study On The Main Circuit Topology And Control Method Of The Series Voltage Transients Compensator Device

With the development of science and technology, the power electronic technology iswidely applied to industrial production and people’s life. Various power electronic devicesemerge as the times require, and are widely used in power systems. This makes the loadstructure produced very big change in the power system, from the previous simple linear loadto now the nonlinear, impact load. Their running and start-stop in the electronic power systemwill bring different interferences to the grid, and make the grid to produce various powerquality problems. Due to the continuous development of science, industrial production beginsto develop to digitization, automation, integration. Sensitive electrical equipment based on thecomputer, microprocessor in widely used in power system, and their requirement of powerquality is very high. Therefore, how to provide high quality electric power, and at the sametime don’t interfere the grid become what the electric power workers concern.In all power quality problems, voltage transient is one of the most important powerquality problems. In the voltage transient problem, voltage sag accounts for a big part. Nowmany scholars put forward various series voltage transient compensator devives to improvethe power quality, such as DVR, UPQC, UPS, DySC etc. Most of these series voltagetransient compensator devices have injection transformer and storage capacitor, this makes thedevice volume big, and because of the limited capacity of the storage capacitor, thecompensator devices compensate for a limited time. This article puts forward a noveltransformer-less series voltage transient compensator without rectifier and energy storagecapacitors based on the series voltage transient compensators in the laboratory. Firstly, thecircuit structure of the new topology is given. The new topology doesn’t have recitifier, sothat the device has smaller volume. At the same time the new topology control strategy isidentified, and the dynamic design of the load voltage waveform tracking control closed loop,bus voltage balance control closed loop, and bus voltage amplitude control closed loop ismade. Then the system hardware design and software design is given on the basis oftheoretical anaysis. Then the simulation platform is built and the study of the simulation ismade. Finally, the system experimental platform is built on the basis of theory analysis andsimulation, and some experimental results are given. The results show that the theoreticalanalysis is correct, and the experimental platform can operate normally.