This thesis deals primarily with the simulation and analysis of shunt active power filters (APF) on a three-phase power distribution system possessing a harmonic generating load. The shunt active power filters are analyzed based on effective total harmonic distortion (THD) levels and response to changing dynamics. These results are derived from the simulation of a pulse-width modulation (PWM) controlled voltage source inverter (VSI) with a capacitor connected to the DC side of the VSI. The primary difference between individual simulations is the particular control law implemented in the shunt APF.