Photovoltaic (PV) energy generation techniques have received significant attention since they utilize the abundance of solar energy and can be easily scaled up. Thanks to the extensive research and development of PV energy generation technologies, various scales of PV energy generation systems have been deployed for many practical applications such as PV power stations, solar-powered vehicles, and solar-powered heating and lighting appliances.

A PV system is organized as a series connection of PV modules where each module consists of a number of series-parallel connected PV cells. PV systems are subject to receive the partial shading effect and PV cell faults, which are serious obstacles to utilize PV systems effectively since they may result in a significant degradation in the PV system output power. PV cell faults decrease the efficiency of PV systems and even shorten the PV system life span. The maximum power point of PV cell varies by both solar irradiance and temperature. The maximum output power of a PV cell rises as increase in solar irradiance level and/or decrease in temperature.

A reconfigurable PV module architecture with integrated switches in a string-inverter PV system solves this partial shading problem cost-effectively. Each integrated switch consists of three programmable switches to facilitate the PV panel reconfiguration. This architecture is able to locate faulty PV cells dynamically. We also research PV module reconfiguration control algorithms to adaptively produce near-optimal reconfigurations of PV module array so as to maximize the PV system output power under partial shading as well as fault detection and tolerance algorithms that bypass the faulty PV cells. The design of computer-controlled programmable switches can be applicable to large-scale PV systems.

Related Papers

[C-14-06] Jaemin Kim, Yanzhi Wang, Massoud Pedram and Naehyuck Chang, "Fast Photovoltaic Array Reconfiguration for Partial Solar Powered Vehicles," to appear in IEEE/ACM International Symposium on Low Power Electronics and Design (ISLPED), 2014.

[C-13-05] Yanzhi Wang, Xue Lin, Massoud Pedram, Jaemin Kim and Naehyuck Chang, "Capital Cost-Aware Design and Partial Shading-Aware Architecture Optimization of a Reconfigurable Photovoltaic System," in Proceedings of Design Automation and Test in Europe (DATE), pp. 909-912, Grenoble, France, 2013.

[C-12-11] Yanzhi Wang, Xue Lin, Naehyuck Chang and Massoud Pedram, "Dynamic Reconfiguration of Photovoltaic Energy Harvesting System in Hybrid Electric Vehicles," in IEEE/ACM International Symposium on Low Power Electronics and Design (ISLPED), 109-114, 2012. 

[C-12-08] Xue Lin, Yanzhi Wang, Siyu Yue, Donghwa Shin, Naehyuck Chang and Massoud Pedram, "Near-Optimal, Dynamic Module Reconfiguration in a Photovoltaic System to Combat Partial Shading Effects," in Proceedings of the Design Automation Conference (DAC), pp. 516-521, San Francisco, CA, USA, 2012.