ISSN E 2409-2770
ISSN P 2521-2419

Reliability Improvement of Micro-Inverter through AC-Ripples Voltage Compensator


Vol. 7, Issue 08, PP. 274-281, August 2020


Keywords: Micro inverter, Reliability, Active Power Decoupling APD, PV system, AC Ripples

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In this paper the resiliency improvement of micro inverter is considered. Its life degrades mainly due to failure of DC link capacitor. The inherent 100 Hz ripples from inverter stage causes excess heat in capacitor. Consequently, the electrolyte dries out quickly and its lifespan decreases. The objective of this paper is to mitigate such AC harmonics on DC link capacitor. A compensator or active power decoupling circuit, APD, is designed in PSIM. The APD circuit is a combination of film capacitor, H-bridge and control circuit. Second frequency AC ripples are converted into DC by actively controlling the capacitor. In this manner AC harmonics are mitigated at the DC link capacitor. Firstly, a benchmark micro inverter is designed and simulated without using APD circuit.  Secondly, active power decoupling is used by designing APD circuit. The simulation results show that there is a decrease in AC ripples from 9.4% to 3.2% by using series voltage compensator as compared to passive power decoupling i.e. only a bulk capacitor. The capacitor life is increased up to 19 years and hence of micro-inverter. The total harmonics distortion (THD) analysis shows that by using active power decoupling, system injects 2.7% THD as compared to passive decoupling which is 1.69%. which is still in bellow the IEEE standard of allowable 5% THD.

  1. Siraj Ud Din,, Department of Electrical Energy System Engineering, US-Pakistan Center for Advanced Studies in Energy, University of Engineering and Technology Peshawar, Pakistan.

Siraj ud Din Reliability Improvement of Micro-Inverter through AC-Ripples Voltage Compensator International Journal of Engineering Works Vol. 7 Issue 08 PP. 274-281 August 2020

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