The Control Strategy Of The Flexible Inverter And It's Simulation Based On Matlab/Simulink

The development and using of the Renewable energy is increasingly concerned by people all over the world, Inverter technology is key to use the renewable green energy such as the solar energy, the wind energy, the biological energy,what's more, inverter is the core of inverter power supply which is widely used in electrical power system, industry, transportation, bank, military, aviation, national defense and so on. Therefore the research of inverter control algorithm has the very vital significance.There are many interference factors to the inverter, such as load perturbations or nonlinear loads, the bridge dead-band control,the fluctuation of the DC voltage and so on.Therefore the harmonic pollution of output voltage is high, the load adaptability is low, the distortion of the output voltage is serious, the stationary precision is low. Each algorithm common used now has it's advantage and disadvantages, specially,it's difficult to have fast dynamic response speed and high stationary accuracy. The control algorithm studied in this article can do it well.The single-phase entire-bridge inverter's electric circuit model and the mathematical model is established in this article, the output voltage influencing factor is discussed,then a kind of compound control algorithm is studied which combine the digital PID control and the repetitive control.The algorithm has many advantages such as the output voltage distortion is small, the anti-jamming ability is strong, the dynamic response is quick, the stationary precision is high, the system stability and reliability is superiorThe algorithm is simulated and analyzed on matlab/Simulink, at last the simulation result is given to confirm the control algorithm's superiority from the theory and the simulation angle. Four control algorithms are compared:the voltage PID feedback control algorithm, the voltage and inductive current double closed loop PID feedback control algorithm, the voltage and capacitive current double closed loop PID feedback control algorithm, the compound control algorithm combining the voltage and capacitive current double closed loop PID feedback control with the repetitive control algorithm.Simulations validate the result that the compound control algorithm has many advantages such as the output voltage distortion is small, the Anti-jamming ability and load adaptiveness is strong, the dynamic response is quick, the stationary precision is high, the system stability and reliability is superior.