Retrofitting of Existing Solar Power Condition Unit as Reactive Power Compensator

Domestic solar PV system involving roof-top solar PV plant, with in-house inverter and battery-pack, is very common in rural and urban areas. A power conditioning unit (PCU) is commonly used as heart of the solar PV plant system, housing DC-DC converter for maximum power point tracking and DC-AC converter as inverter to drive the domestic AC loads. This paper proposes to retrofit the existing power conditioning unit supplied from solar PV and battery energy storage system (BESS), to supply reactive power to the grid for compensation. An experimental setup consisting of 540 W solar PV module with 24 V, 42 Ahr battery supported PCU has been reconfigured as reactive power compensator in a single-phase 230 V grid, loaded with multiple induction motors, drawing the reactive power. The PCU is able to inject maximum 1 kVAr reactive power into the grid. The solar PV under this condition continues to charge the BESS with small $2.5 \%$ of real power to support the system losses. This combination can maximizes utilization of solar PV plants. The MATLAB simulation is employed to verify the performance of the proposed system under various availability combination of input sources. An experimental setup is used to retrofit the 1.0 kVA PCU as reactive power compensator.