The Application And Research Of Freestanding Photovoltaic Power System In Energy Efficient Building

Because the situation of lacking primary energy resource and its accompanying energy insecurity are becoming more and more serious, proper exploitation of solar energy has been assigned increasing significance. Building Integrated Photo-Voltage (BIPV) technology brought out a new concept that building produce energy, which has become a dominant trend for photovoltaic technology in terms of its tech-superiority currently. Freestanding photovoltaic system is an important research field of BIPV technology.Based on the bulks of reference on photovoltaic industry's development home and abroad, along with fundamental components and basic principle of photovoltaic power system, the principle of conversion from solar energy to electricity, output characteristic of solar cell, and the work principle and way of lead-acid battery that is an important component of solar power system were discussed. How to design installation capacity of solar cell array and battery was also further addressed. Based on this discussion, a method of controlling on charge and discharge for battery used in photovoltaic power system with a freestanding power supply was put forward, and an intelligent controller whose core was a single ship computer named p89c58x2 produced by Philips was invented. The controller has the ability to acquire data and had perfect man-machine conversation interfaces. It also has asynchronous communication interface according with both RS232 and RS485 protocol. According to the battery's voltage, the controller is able to adjust systematic input produced by photovoltaic array, systematic output offered to load automatically, start and stop of standby power supply, in order to ensure the photovoltaic power system can always run steadily.Taking a special project of applying a photovoltaic power system with a freestanding power supply in an energy efficient building as an example, a method of designing freestanding photovoltaic power system was given, and the issue that how to ascertain the radian of photovoltaic array were discussed in particular. The real-time operating test showed systematic stable operation under control of devised controller and satisfactory effects. Based on analyzing on the data acquired by the controller, some proposals for systematic optimization were given, serving as beneficial reference to similar system's design.