The Study And Design On Electric Actuator Driving Power Supply Based On VF Speed Regulation Technique

Variable frequency(VF) driving power supply as an important part of electric actuator, which has high fault rate because of frequently on-off in operation. Space vector control as an advanced control strategy of VF speed regulation technology can effectively resolve it. Its main concept is to transform the model of AC motor to DC motor via coordinate transformation, and further to decompose the stator current into two DC parts of oriented the rotor direction of the magnetic field and achieve an effect of DC motor control. With the supervisor's research project (The localization research and system integration of the imports SIPOS electronic actuator), we designed a electric actuator driving power supply system based on space vector pulse width modulation (SVPWM) control technique and improve the power performance, reduce the fault rate.The major contribution of this paper is summarized as follows:( 1 ) Introduce the development of electric actuator and VF speed regulation technique at home and abroad. Many control algorithms as equivalent PWM, SPWM, current tracking PWM and direct torque control PWM are compared. And it is analyzed advantages and disadvantages in this paper.(2) Using the converter vector control algorithm based on SVPWM and the singlechip SAF-C161PI-LM improved the quality of the PWM wave. The algorithm of SVPWM that is adopted by the system implements speed regulation by control of magnitude and phase of space flux linkage and can generate less harmonics of inverter output current, reduce ripple torque, and increase availability of voltage.(3) It is designed the hardware circuit of this power supply system, including main circuit topology of AC-DC-AC VF system, Electro magnetic Interference (EMI) filter circuit, Insulated-gate Bipolar Transistor (IGBT) gate driving circuit, high frequency transformer, switching power supply module, power supply monitoring, overcurrent detection and overvoltage detection etc. It is greatly improved the protection of the motor.(4) It is simulated and analyzed SVPWM vector control algorithm of this VF speed regulation system combined basic principle of vector control and hardware design and PSIM simulation software. It is presented simulation waveform, validated correctness and applicability of system theory, and provided guidance of making the sample. It is written system software program based on theory analysis.(5) Through a series experiment of the sample, inverter control strategy, VF speed regulation, and Field tests achieved trouble-free operation from march 2008 to now , that proved highly reliability of the power system.