The Study On Key Issues Of Voltage Source Converter For Superconducting Magnetic Energy Storage System

Superconducting Magnetic Energy Storage (SMES) is a product of the combination of the power electronics technology and superconductive technology. Compared with the traditional flywheel and battery energy storage, the new energy storage method should be paid more attention because of many good performances such as low energy loss and rapid response ability for no need of other energy conversion and has been applied to electronic devices used in power system as energy storage installation, such as dynamic voltage restorer, short circuit current limiter and so on.The converter in SMES system is often called Power Conditioning System (PCS). As the bridge between the utility grid and SMES coil, PCS is an integral part of the design of any SMES system. It plays an irreplaceable role in solving the questions such as the power quality and supply reliability for the ability to control the active and reactive power of SMES system independently and rapidly.For the voltage sags has become one of the most severely affected power quality problems with great economic loss, a PCS for High Temperature SMES (HT-SMES), based on carrier phase shifted SPWM, is put forward to solve the instantaneous voltage drop faults. With closed loop control arithmetic, the amplitude and phase of fault voltages are tested and compared with the normal values in order to give the proper voltage compensation values. By applying MATLAB/SIMULINK simulation software, control arithmetic simulation is carried out and the results show that the control method can compensate the three phase fault voltage fast and accurately.At meanwhile, a main circuit topology is proposed. The control system hardware circuit, signal conditioning hardware circuit, power and drive circuits are set up respectivly. By compiling correlative software program and using 32-bit fixed point DSP TMS320F2812, instantaneous voltage drop compensation is realized.At last, comparison with the voltage waves of before and behind compensation in power system dynamic simulation experiment prove the validity of the instantaneous drop voltage compensation device.