Comparative Analysis of Multiple-pulse VSC-Based STATCOM’s for Voltage-Dip Mitigation

This paper includes the performance of a Flexible Alternating Current Transmission Systems (FACTS) device, namely, STATic synchronous COMpensator (STATCOM) based on 6, 12, 24 and 48-pulse Voltage Source Converter (VSC), for the mitigation of voltage-dip caused by the starting of a high power induction motor. The different configuration of the STATCOM’s implemented improves the voltage profile feeding to a high power induction motor at starting by injecting a controllable current to the supply line having an acceptable limit of harmonics as per the standards of IEEE. The capability of the STATCOM’s to compensate the reactive power to the system when the voltage dip occurs due to starting of high power induction motor load is described. The 48-pulse VSC employed in the STATCOM injects an almost sinusoidal current of variable magnitude, in quadrature with the line voltage, thereby emulating an inductive or a capacitive reactance at the point of connection with the line and introduces a very less amount of harmonics in to the system. Author has developed all the multiple-pulse VSCbased STATCOM’s and implemented it into a power-system consists a high power induction motor in MATLAB/Simulink environment to show the voltage-dip mitigation capability. The harmonic contents to be introduced by the different configurations of the STATCOM’s are also shown by the author.