Off-grid Wind And Solar Hybrid Generation System

With the energy crisis of fossil fuels, nuclear leak in Japan alarms to mankind.As an inexhaustible, non-polluting and clean energy, solar energy and wind energyare considered as the most effective energies to solve the energy crisis. Solar andwind energies are highly complementary, and wind and solar hybrid generation is anew energy power generation mode because it can make up for alone intermittent,unstable defects of wind or solar power, and take advantage of low cost. With thedevelopment of new energy technologies, a number of wind and solar controlproducts have been developed in the market, but they are not popular because of thecomponents of the system are very expensive and the key technologies are owned bya few people.Based on the above reasons, an off-grid wind and solar hybrid generation systembased on DSP2812is developed in this thesis. Making full use of the energy of solarpanels and wind turbines, the system is powered by solar and wind energy. Thebatteries are charged by using double perturbation method tracking the MaximumPower Point, and the battery management is realized by using temperaturecompensation function. The system is designed to work in an environment-friendlyand energy-saving power supply mode. And it can avoid some controller’s defects inthe market.The system consists of solar panels, wind turbines, charging circuit, DSPintelligent controller, batteries, push-pull inverter circuit, LED constant current drivecircuit, the auxiliary power supply circuit and data acquisition circuit. The system isprovided by solar and wind power, and a two-stage battery charging mode withtemperature compensation is used. When the night is coming, the AC incandescentand DC LED billboard are lighted. When the battery voltage reaches to theover-discharge voltage, the system sounds a warning of the electricity shortage andthe battery’s discharge circuit is cut off so as to protect the battery. The state of solarpanels, wind generators, battery components and load is acquired in real-time, inorder to achieve the intelligent controlling of the system and make the system workstably and reliably.In the hardware, the effect of the sources side inductance and Miller capacitance on the MOS driver tube is analyzed, and mitigation schemes are proposed. Based ondifferent MOS application requirement, three drive schemes are developed: IR2110isused in solar charging circuit to drive MOS transistor and shutdown circuitry isdesigned; IR2104is used in constant current PWM of driving LED billboards;TLP250is used in wind machine’s boost circuit. Algorithm of the transformer isstudied, the problems about transformer saturation are discussed, reasons of MOStransistor burning are analyzed and the protecting measures are proposed.In the software, the control flows of the wind and solar power hybrid generationsystem, the charging and discharging management strategy of the battery and theflows on PWM and SPWM by using DSP2812are explained in detail.The designed off-grid wind and solar power hybrid generation system has thefunctions of overvoltage, undervoltage, overcurrent, anti-reverse, anti-lightningprotection and so on, and it can work normally and stably.