V Jayalakshmi, M.Kalavathy
Abstract: The Static Synchronous Compensators (STATCOMs) have been recognized as the most effective solution for dynamic reactive power compensation, voltage stability enhancement and sub synchronous resonance damping purposes in the electric power systems. The STATCOMs in the distribution utilities (DSTATCOMs) are increasingly investigated for dynamic reactive power compensation and power quality improvement in the distribution utilities.This paper presents an investigation of seven-Level Cascaded H - bridge (CHB) Inverter as Distribution Static Compensator (DSTATCOM) in Power System (PS) for compensation of reactive power and harmonics. The advantages of CHB inverter are low harmonic distortion, reduced number of switches and suppression of switching losses. The DST ATCOM helps to improve the power factor and eliminate the Total Harmonics Distortion (THD) drawn from a Non-Liner Diode Rectifier Load (NLDRL). Finally a level shifted PWM (LSPWM) and phase shifted PWM (PSPWM) techniques are adopted to investigate the performance of CHB Inverter. The results are obtained through Matlab / Simulink software package.
Keywords: DSTATCOM, Level shifted Pulse width, Modulation LSPWM, Phase shifted Pulse width modulation PSPWM, Proportional-Integral PI control, CRB multilevel inverter, D-Q reference frame theory