Research And Design Of Inverter In Dual-PWM Converter Controlled By Single DSP

With the globally increasing of energy consumption, energy saving technology is being one of the hot topics of the scientific research field.In modern industrial area, electrical power is mainly used for motor power supply, therefore, developing high performance motor controllers will have great significance on energy-saving, product quality and productivity improvement. Dual-PWM inverter control systems have the advantages of four quadrant running, adjustable power factor and the dual energy flow. Research and development of high performance dual-PWM inverters will not only conform to the development trend of frequency control, but also have great economic benefit and practical application value.Firstly, the development of AC adjusting speed technology and the research status of dual-PWM inverter control systems at home and abroad are analyzed. Starting with the main circuit topology of the dual-PWM system, the basic principles of the rectifier and inverter side are analyzed and the closed-loop control structure design is introduced. Secondly, on the basis of coordinate transformation, the mathematical model of asynchronous motor is established under the three phase static coordinate system and the rotating coordinate system, on this basis, asynchronous motor control strategy and its implementation of invert side are studied respectively, with emphasized studying on vector control strategy which based on the rotor flux orientation. To control the DC bus voltage better, and make it have a smaller fluctuation and faster dynamic response properties, motor power feed-forward control scheme is analyzed, and this scheme is also improved furthermore, the new dual PWM combined control scheme which based on motor power feed-forward principle is proposed. Then, under the MATLAB /Simulink circumstance, the inverter side and dual-PWM integrated control system are simulated, whose results show that the control system has good dynamic response and steady state accuracy. Furthermore, simulation is also conducted on the new dual-PWM combined control scheme which based on motor power feed-forward principle, and the simulation result is compared to the scheme without using power feed-forward principle,it shows that the new dual-PWM combined control scheme has a better effect to control the DC bus voltage.Finally, In order to get fine current tracking, voltage tracking, harmonic restraint and disturbance rejection, the AC inductance and DC capacitance of there-phase dual-PWM system are designed optimally. A TMS320F28335-based experimental platform of three-phase dual-PWM control system is presented and relative software and hardware circuit are designed.