oa Design Of Shunt Active Power Filter For 3X5 Matrix Converters To Eliminate Harmonic Distortion In Input Current

The matrix converters are silicon based converters without bulky and expensive DC link capacitors other than its counterpart voltage source inverter (VSI) converters as an ideal voltage source and feed to ideal current source. Power electronic converters are a typical source of harmonic currents and during each switching cycle, the matrix converters produce unwanted harmonics and this will inject back to the AC mains. This harmonic current effect the overall operations of an AC supply. The main approach to the mitigation of this power quality problem is providing a filter in input side of the converter. Conventionally, passive filters with LC component were the choice for the elimination of harmonics and to improve power factor. These passive filters have the disadvantages such as large size, series and parallel resonance and fixed compensation. Active filters avoid the disadvantages of passive filters by using a switch mode power electronic converter to supply harmonic currents equal to those in the load currents. Active power filters can compensate both harmonic and reactive power simultaneously. In design of an active filter for matrix converter, a high displacement angle of input line current may compensated by matrix converter itself setting as reference for the input current a lagging displacement angle. It makes the reduced voltage transfer ratio for the system. So the control of the impedance interaction between the input filter and the voltage converter is mandatory. This paper propose a shunt active power filter for a 3x5 matrix converters to eliminate harmonic currents and to compensate reactive power for linear and non-linear loads. The paper presents the various design aspects of shunt active power filter for a 3x5 matrix converter. The control logic is made by using p-q theory and calculated the reference currents in order to compensate zero, harmonic and reactive currents (Fig. 1). To validate the proposed filter design, matlab simulation tests are conducted and results are presented. Simulations are carried out for the RL load and analysed the output with and without filter. These results shows less harmonic distortion in input current as well as reduced total harmonic distortion by using a simple active filter in input side. This proposed methodology has good results as compared with the conventional input filter. Fig. 2 presents simulation results of 3x5 matrix converter without any input filter. 80% of total harmonic distortion (THD) is reduced after accommodating an active input filter in to the same system (Fig.3).