Leakage current alleviation in solar energy conversion system enabling power quality improvement

Abstract

This work presents a generalised integrator-based control algorithm for power quality (PQ) amelioration of the grid in the presence of non-linear load enabling leakage current suppression feature. Owing to the presence of stray capacitance between solar photovoltaic (PV) array and the ground, the variation in common-mode voltage across stray capacitance leads to potential safety issues, electromagnetic interference, and distortion into the injected grid currents. Furthermore, the PQ of the grid is highly deteriorated under the existence of non-linear loads. To solve the aforementioned issues, the harmonic compensation controller is presented herein to ensure the unity power factor operation, harmonic compensation, leakage current suppression using the grid-connected solar PV array system. Simulated results show the effectiveness of the control strategy under various operating scenario. In contrast to the state-of-the-art techniques, the grid currents are attained sinusoidal and balanced even in the presence of unbalanced non-linear load. Furthermore, the leakage current is suppressed within 300 mA as per the VDE-00126-01 standard. The comparative performance explicitly validates the effectiveness of the presented harmonic compensating strategy over the conventional schemes. Test results manifest the response of the solar PV array system for various operating conditions and follows the revised IEEE-519–2014 sand VDE-00126-01 standards.