This paper presents the three topologies of three-phase four-wire DStatcom for reduction of harmonics, reactive power compensation, increasing power factor, which occur due to a nonlinear load, environment problem and polluted grid. The performances of the above topologies have been compared for the magnitude of source current, power factor improvement, DC-link voltage regulation, and total harmonic distortion. This paper presents a novel work for the new young scientist /industrialist who working in the improvement of power quality in the grid. This paper helps to provide the application, designing constraints of shunt active filter in many fields. The First topology which is used in this paper is the three-phase four-wire four-pole voltage source converter based DStatcom. The second is the three-phase four-wire with three-leg voltage source converter based DStatcom with T-connected transformer and the third topology is the three H-bridge voltage source converter based DStatcom. The T-connected transformer in the second topology has been used to reduce the rating for voltage source converter. Synchronous reference frame theory based controller has been proposed to the generation of the reference current. Reference current generated from the synchronous frame theory is processed to hysteresis current controller loop which produces switching pulses for VSC based DStatcom. All these topologies have been implemented in MATLAB /Simulink platform by using different types of loading conditions such as resistive and power electronics load.