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The Microgrid is a combination of the distributed generation (DG) systems that deliver power to its local networks. The DG system constitutes non-conventional sources such as wind turbine, fuel cell, battery, and Solar. By connecting microgrid to the non-linear loads, it generates harmonic current into the system, which disturbs the sinusoidal waveform and power factor. The power quality compensator is used for improvement of the reliability and efficiency of the system. In this paper, first power quality issues are analyzed by connecting loads. As the system is connected to load it disturbs the sinusoidal waveform by introducing harmonics. To reduce these harmonics, passive filters are used. But due to the certain drawbacks such as complication in design and huge size of filter shunt active power filter (SAPF) is introduced in this system. These SAPF is controlled by an instantaneous power theory, which works as on line power quality analyzer and limits THD according to the IEEE 519-1992 standard. Depending on the power requirement of the nonlinear load, the proposed control for SAPF allows balanced line with near sinusoidal current and also maintains unity power factor. The presented model is simulated in the Matlab/ simpower environment and results are validated.

Due to environmental conditions, the wind power generation is fluctuating in nature. This affects the electrical network interconnected with these systems. When the wind power generators are connected to the nonlinear loads, there is distortion in the waveform. These distortions should be within limits according to national and international guidelines framed for power quality. This paper presents a mitigation technique with a shunt active filter, which reduces harmonic distortion to the permitted limit. Sine pulse width modulation (SPWM) control scheme is used to control shunt active filter. This technique eliminates harmonic distortion and maintains unity power factor. The simulation for proposed method is carried out using MATLAB/SIMULINK and results are validated.

This paper proposes a new pulse width modulation (PWM) technique to overcome the low performance of a conventional pulse width modulation control strategy for an active filter. In this design, the desired output voltage is achieved by comparing the desired reference waveform (modulating signal) with a high-frequency triangular ‘carrier waveform’. By this scheme, the voltage source inverter can be controlled by the sine pulse width modulation technique (SPWM) with the DC voltage amplitude and finally the total harmonic distortion (THD) can be reduced to the limit of IEEE harmonic standard. The performance of the SPWM technique and the harmonic limit is analyzed using Matlab-Simulink toolbox