Design and Analysis for High Performance Synchronized Inverter with PWM Power Control

Abstract

This paper presents simulation results of a high-performance single phase Sinusoidal PWM inverter compared to traditional SPWM type. The proposed inverter uses a suitable Voltage Controlled Oscillator (VCO) that to produce variable carrier frequency controlled by full rectified wave reference grid voltage. The reference grid voltage is compared with output triangular carrier wave of the VCO to generate variable frequency PWM pulses. An electronic controller is also designed to stabilize the fluctuation of the DC voltage supply that can occur in renewable energy sources such as solar or wind which is assumed to be an input to the power electronic circuit of the proposed inverter. The simulation results show reduction in the Total Harmonic Distribution (THD) when using variable carrier frequency compared with the traditional fixed carrier frequency SPWM. On the other hand, the controller show effective range of Modulation Index (MI) controlling from 0.77 to 0.89 when the DC supply voltage is varying from 350V to 300V with capability to modify the controlling range of MI. satisfactory AC output specifications are obtained from the simulation results that may lead the proposed design to be considered for practical implementations using general purpose discrete components without the need of special DSP chip.