Ramp-Rate Limiting Inverter Control Using Predicted Irradiance

Reliability is the most important aspect of solar PV performance. There are several components in solar PV systems, but the inverter is the most crucial component that is vulnerable to failure. Among the factors affecting the reliability, the ramp rate of solar PV power is one of the factors that can be controlled using the control strategy. This paper demonstrates an enhanced control strategy using the irradiance prediction and rate of irradiance change. In this control strategy, the output voltage and current from the PV panel are fed into a physics-based model of the PV panel to calculate the irradiance. The calculated irradiance is compared with a data-driven model trained using realtime measurements. This prediction allows us to improve inverter performance by reducing the ramp rate by up to 70%. The proposed method improves life expectancy by reducing stress on the inverter. Simulation results are included to show the effectiveness of this approach.