Research And Design Of Stand Alone Wind Solar Hybrid Power System

Comprehensive utilization of renewable energy plays an important role in society and economy sustainable development and environment protection. Wind and solar energy have a good complementary in resource conditions and technology applications as two widely applied energy. Wind solar hybrid power system may make up some shortcomings of low reliability and high cost in wind power system and solar power system individually, and it has a wide application field which can be applied in communication relay station, city lightning engineering and so on. So research on wind solar hybrid power system has important theoretical signification and utility value. The main contents are summarized as below:The structure characteristics and operation principle of wind solar hybrid power system are analyzed. Work characteristics of the key components and their important functions playing in system are expatiated in detail. It makes a theoretical foundation for proposing control strategies and design of hardware and software for wind solar hybrid power system.Maximum power point tracking and their circuit realizing method are studied, the double input DC-DC converter is adopted to realize wind and solar energy can input synchronously and to realize maximum power point tracking control of two energy, the control strategies of maximum power point tracking which adopts perturb & observe algorithm is given; Boost/Buck DC chopper combined with three states charge method is used to realize charge and discharge control of storage battery, its circuit and control are simple and easy to realize; Six battery energy allocation model are proposed according to DC bus voltage judge method.According to system control strategies, hardware circuit of wind solar hybrid power system is designed preliminarily including sampling circuit, charge and discharge control circuit, drive circuit, protection circuit and power supply circuit; and system software flowcharts are given including system main program, storage battery charge and discharge control subprogram, solar power system subprogram, wind power system, perturb & observe Algorithms subprogram.The mathematical model of the solar cell, wind turbine generator and storage battery are established and simulated in MATLAB/SIMULINK, the simulation results show that solar cell has strong nonlinear; At last the simulation of storage battery charge and discharge system based on fuzzy-PID control is studied, the simulation results show this control method can improve effectively system dynamic performance.