A Multi Level Inverter (MLI) based Shunt Active Power Filter(APF) is considered in this paper. Single MLI-APF is used as both Interfacing converter that processes and connects generated PV power to grid and also for improvement of power Quality of the Whole system. As Majority of the Renewable systems comprises at least two converters for these tasks, the proposed system may be treated as simple and economical in meeting the same objectives. Use of MLIs reduces stress on power electronic

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... because they can be made to operate at low voltages compared to the conventional two level converters. The output voltage provided by MLIs has small voltage steps, that results in good power quality and low-harmonic components. Peak detection method of control strategy is employed in MLI-APF for power quality improvement. P&O algorithm is used for achieving Maximum Power Point Tracking of the PV generator. The proposed system is simulated using MATLAB/SIMULINK and tested for power quality improvement under the maximum Power Point Tracking of PV generator. established to 1) control the converter dc-link voltage to extract the maximum power from the PV system, 2) generate the reference current for the MLI-APF to compensate the harmonics and regulate the power factor of the system. RELATED WORK: The main objective of the SAPF is Generation of reference currents for which many strategies are available in literature. The mostly used instantaneous p-q theory can provide an instantaneous and accurate reference compensating current [4,5] but suffers from the requirement of reference frame transformation from a-b-c axes to d-q axis. The Synchronous Reference Frame (SRF) strategy [6] only computes the sinusoidal fundamental components of the load currents; the reactive power compensation and a zero neutral current thus cannot be achieved if the load imbalance at the fundamental frequency occurs. A phase-locked loop (PLL) per each phase must be used. Grady et al. [16] have presented a survey of active power line conditioning methodologies with a list of the advantages and limitations of each one. Cavallini and Montanari [17] have proposed the unity power factor strategy known as classic strategy in which conditions the line currents to fit the voltage waveform, provides line current RMS values always lower than those obtained by keeping the instantaneous real power equal to its mean value. Chang and Shree [18] have proposed a simple and efficient compensation strategy that is suitable for three-phase shunt active power filters without reference-frame transformation requirement. In addition to these there are several other techniques such as extraction of load current RMS component [7] , indirect current control [8] , algorithm based on the real component of fundamental load current (I cosF) [9] etc.,