A Efficient Photovoltaic System With P&O-Based Maximum Power Point Tracking

In recent years, energy shortages and environment pollution have constrained sustainable development of human society. Search for new energy has been one of human facing pressing issues. Solar energy, as a new energy production, has been concerned more and more for its pollution-free, unlimited, and maintenance of simple measures. According to the requirements of developing photovoltaic power generation system, which is one of solar energy's important research areas, a efficient photovoltaic system with P&O-based Maximum Power Point Tracking (MPPT) was proposed in this thesis.At first, with overview of the development of modern photovoltaic power generation system, the research target and design objectives of the controller were presented. According to the features of small power PV system, such as small output power of solar cells, low system cost, and high requirement of conversion efficiency, analog circuit design is used to implement the controller. Analog IC controller features simple structure, small size of silicon, and simple application.Based on the design target of chip system, the system architecture of the controller was proposed.Then, after completing the system architecture, some key modules like analog multiplier, analog differentiator, reference voltage, current sense module, and oscillator were designed and simulated in 1.5um BCD technology. In particular, the linearity and input range of multiplier, and the stability and settling time of differentiator are all optimized for system requirement.The controller chip was completed based on the system architecture and circuit modules. Some typical characteristics of system were simulated and analyzed. The system simulation results showed all specifications of the controller were successfully achieved.