A Study on the Reduction of 120 Hz Ripple Voltage Effect and Current Distortion Rate by the Compensation of Reactive Power on Single-phase Photovoltaic Systems

The RL load can be connected to the grid side of a photovoltaic (PV) power generation system. When the RL load is active, the power factor of the grid decreases owing to the reactive component of the current. The reduction in the power factor can be solved by generating a reactive current using the DC-AC inverter. However, compensating for the reactive current increases the 120 Hz ripple voltage component that occurs in the DC-Link. The increase in the 120 Hz ripple voltage follows the compensation of the reactive component, and increases the distortion rate of the grid current, thereby degrading the overall performance of the PV power generation system. This study proposes a power factor reduction compensation scheme that occurs when driving a RL load in a single-phase photovoltaic system. Moreover, a grid current distortion reduction scheme is proposed to reduce the effect of 120 Hz ripple voltage component. The validity of the proposed scheme is investigated through simulations and experiments.