Intelligent Control Applied Research In The Current-controlled Voltage Source Inverter

Current Control Voltage-Source inverter (CC-PWM Inverter) is applied widely in many industry fields because of its excellent dynamic performance. This paper analyzes the main principle, characteristic and research development of CC-PWM inverter, establishes the mathematical model of CC-PWM inverter based on the switch function, summarizes the existed current control techniques at present, besides discusses and compares the advantage and disadvantage of them. In order to avoid the current ripple and the high switch frequency of fixed-band hysteresis current controllers, two hysteresis controllers of change hystersis-band are proposed. One is the sinusoidal-band hysteresis current controller, the other is the adaptive hysteresis current controller based on fuzzy theory. These improved hysteresis control schemes can ameliorate dynamic performance and decrease the tracking error of load currents. Experiment results verify the validity and feasibility of them and their control performances are compared at length. Then, the CC-PWM linear current control strategy is also studied in detail in this paper, and two improved self-adaptive PI controllers are brought forward on the basis of fuzzy logic control theory and fuzzy logic neural network control theory which sufficiently takes advantage of self-learning capability of neural network. They can greatly improve the dynamic performance and CC-PWM system can achieve fast system dynamic response. Simulation result shows that they are effective. At last, the three-level PWM inverter control scheme is simply analyzed and a simple SVPWM method is presented.