Static VAR compensator and active power generator using photovoltaic inverter for industrial application.

Abstract

The work involves the design and construction of a active power filter (APF) for VAR compensation and unity power factor correction. The approach taken can be summarized as follows. A thorough study of inverter topologies suitable for VAR compensation and unity power factor correction using photovoltaic (PV) was carried out. Several possible topologies are investigated, namely the shunt active power filter, series active power filter and hybrid active power filter. The hybrid active power filter type inverter was selected. The merit of this topology is its cost-effectiveness and improved performance. The particular important contribution is the proposition of a new variation of hybrid active power filter topology. The topology is unique because it effectively filters harmonic currents of low and high frequencies to obtain sinusoidal source current and unity power factor. Furthermore, it simultaneously supplies the power from the PV array to the load. Another contribution is the use of extension p-q theorem to estimate the compensation current reference. Using this theorem, the resulting equations for the current reference is simpler. This will lead to more efficient implementation using digital method. A system modeling and simulation of this topology is performed using MATLAB/Simulink. Then the construction of a 500 VA inverter system based on the preliminary design and simulation was carried out. These include selection a suitable processor (and specifying its tasks), design of the hardware components such as sensors, signal electronics, drivers and power circuit. Several tests to validate the performance of the APF in actual environment were carried out. The tests include “burning-in� the APF with nonlinear load over long period. The prototype was found to be working well under the specified test conditions.