Supercapacitors Fast Ageing Control in Residential Microgrid Based Photovoltaic/Fuel Cell/Electric Vehicle Charging Station

Abstract

The demand for microgrids and their applications in buildings, industries and for very specific applications is increasing over time. Most of these microgrids are dependent on renewable energy sources, which brings along problems of intermittent energy production. To maintain the balance of the grid, normally storage devices are used. Supercapacitors (SCs) are emerging as one of the potential solutions to solve the issue of intermittent energy production by renewable sources because of their high-power densities and rapid charge/discharge capability. In other terms, SCs can charge, and discharge rather quickly as compared to traditional lithium-batteries. This usage makes it interesting for optimizing decentralized energy generation-based PV systems operations. In this paper, the authors propose the supercapacitors fast ageing control in residential microgrid, including electric vehicle charging station based Photovoltaic-Fuel Cell system. Supercapacitors fast ageing control concept focuses on keeping the electrical parameters of the SCs around the optimal operation points by smoothing the power fluctuations in the system. The used SCs model is essentially based on the intermittent current waveforms along with variable temperature conditions. It enables us to describe the degradation of the supercapacitor’s parameters based on the effects of the temperature and the DC-current undulation. To maintain the electrical parameters of SCs around the optimal operation points, the authors propose a new control based on maintaining the SCs resistance at a minimal level and its capacitance at a maximal level by adjusting the SCs current control according to the optimal operating points tracking. The results validate the effectiveness of the approach, this is important because controlling the fast degradation of capacitance optimizes the lifetime of SCs system. Future research may explore scalability to large microgrids and integration with diverse renewable energy systems.