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

© The Institution of Engineering and Technology
Received 27/12/2019, Accepted 30/03/2020, Revised 02/03/2020, Published 31/03/2020

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.

Inspec keywords: photovoltaic power systems; power factor; invertors; power system harmonics; power harmonic filters; leakage currents; electric current control; electromagnetic interference; power supply quality; power grids; active filters; harmonic distortion

Other keywords: solar energy conversion system; current alleviation; stray capacitance; control strategy; power quality amelioration; two-stage grid-connected solar PV array system; harmonic compensation controller; solar irradiation; PQ; nonlinear load; power quality improvement; solar photovoltaic array; leakage current suppression feature; unity power factor operation; presented harmonic compensating strategy; injected grid currents; current 300.0 mA; generalised integrator-based control algorithm; potential safety issues; total harmonic distortion; unbalancing factor

Subjects: Electromagnetic compatibility and interference; Other power apparatus and electric machines; Power supply quality and harmonics; Control of electric power systems; Power convertors and power supplies to apparatus; Current control; Solar power stations and photovoltaic power systems

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