Hot-spot reduction and shade loss minimization in crystalline-silicon solar panels

The use of solar energy to produce electricity through photovoltaic (PV) systems has significantly increased in the past decade due to (a) reduction in solar panel costs, (b) climate concerns, and (c) advances in power electronics for grid-tied applications. In conventional rooftop PV deployments, solar panels are connected in series with bypass diode(s) across each panel to reduce the effect of shading. Shading results in hot-spots which affect both short-term (power output reduction) and long-term performance (reliability) of a PV system. This paper presents a new technique to reduce hot-spots in shaded cells along with minimizing power dissipation in an overall PV system. The proposed topology is evaluated and compared with various existing topologies with the proposed technique showing superior performance in reducing hot-spots (by 17%) along with lower losses under shading conditions.The use of solar energy to produce electricity through photovoltaic (PV) systems has significantly increased in the past decade due to (a) reduction in solar panel costs, (b) climate concerns, and (c) advances in power electronics for grid-tied applications. In conventional rooftop PV deployments, solar panels are connected in series with bypass diode(s) across each panel to reduce the effect of shading. Shading results in hot-spots which affect both short-term (power output reduction) and long-term performance (reliability) of a PV system. This paper presents a new technique to reduce hot-spots in shaded cells along with minimizing power dissipation in an overall PV system. The proposed topology is evaluated and compared with various existing topologies with the proposed technique showing superior performance in reducing hot-spots (by 17%) along with lower losses under shading conditions.

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