With the developing of the global economic, energy and pollution problem is becoming increasingly acute. As the renewable energy resources which are inexhaustible and definitely clean, solar power is being paid more and more attention by lots of countries. The stand-alone photovoltaic system is considered properly to provide the power to the people who live far away from the city. In this paper, the development situation and the application prospect are discussed, and the whole stand-alone photovoltaic system is designed.In this paper, the basic principle of stand-alone photovoltaic system is introduced. And the characteristic and difference with the methods of maximum power point tracking is researched. As is known, all kinds of things stand around our house such as trees and wire pole. Solar array shaded by those tall things is not unusual. Under this condition, the traditional methods of MPPT control are no longer efficient. To solve this problem, the MPPT methods based on improved Particle Swarm Optimization Algorithm is designed. Through the simulation and practice, it is demonstrated that new methods of MPPT can improve the velocity and efficiency of the system.Based on the analysis of Lead acid battery and super capacitor, a control principle of hybrid energy storage system is brought up. As is proved thought the practice, new principle reduces the cycle number of Lead acid battery, and extends its life.In this paper, structure of PV system, controlling flow of MPPT, controlling block of hybrid energy storage system is designed, and DC module, signal acquisition module, driving circuit and protecting circuit is designed. At last, the experimental waveforms are given. |