MODELING AND SIMULATION OF A THREE （建模与仿真的三个）.pdf

Armenian Journal of Physics, 2009, vol. 2, issue 4, pp. 307-316 MODELING AND SIMULATION OF A THREE-PHASE INVERTER WITH RECTIFIER-TYPE NONLINEAR LOADS 1 2 Jawad Faiz and Ghazanfar Shahgholian 1 School of Electrical and Computer Engineering, Faculty of Engineering, University of Tehran, Iran Phone: +9821 Fax: +9821 E-mail: jfaiz@ut.ac.ir 2 Department of Electrical Engineering, Islamic Azad University, Najafabad Branch, Najafabad, Isfahan, Iran Received 2 September, 2009 Abstract Nonlinear loads generate harmonic currents and voltages in power systems. This paper investigates the effect of inverter output multiple-filter with nonlinear loads on the inverter input current and load voltage. To verify the proposed filter, various simulation results using Matlab/Simulink are presented under nonlinear loads. 1. Introduction In recent years, there has been a considerable increase in the use of uninterruptible power supply (UPS) to provide a low output voltage distortion, fast dynamic response, high reliability and continuous power supply systems especially for sensitive and critical loads, which cannot afford have unexpected power failure. Critical loads such as computer systems, hospitals and air line reservation systems need UPS [1]. Low total harmonic distortion (THD) and high efficiency are commonly required in high power applications, such as three-phase inverter systems. Nonlinear loads and non-sinusoidal currents can cause more voltage drops on the supply network impedance r