Application Of The Frequency Of Control Technology In Intelligent Electric Actuators Based On DSP

With the development of the industry, important status of the electric actuator gradually appears in the industry scene control, but the traditional intelligent electric actuator uses AC motor combine with gear cluster and worm,because of motor speed is constant, only can depend on gear cluster change speed, but the implementing agency once leaves the factory the gear cluster then to be unable to change, so regardless of in the normal operation condition or under the emergency, the valve on/off the speed all not to be possible to change. In addition, when motor direct starting will generate great starting current, having impact to the motor, reducing the life of motor, when the motor shutdown is unable to slowdown inadvance, resulting the action of shutoff impact to the machine part.This paper analyzes the research situation and future development of the electric actuator home and abroad, aim at the shortcomings of the original electric actuator only can run in low speed, through the strong fine-tuning to amend the tiny deviation, proposing intelligent electric actuator meet with a various of valves, using technology of digital frequency, technology of single-chip,micro-electronics technology, developing the integration of implementing agencies, drive units, regulation of control unit as the intelligent electric actuator. In this paper, the design of the intelligent electric actuator includes control part, drive unit, signal detection part. The control part includes controlling chip of DSP, frequency control module, intelligent power module, rectifier module,switching of input and output channels, fault detection circuit;drive unit includes drive motor and mechanical transmission unit; detection part includes voltage, current, temperature detection. Combining laboratory self-developed MMB (micro-message-bus) system, using the method of the direct torque control to controlling frequency,and configuration online, achieving the frequency control of actuator motor, achieving the motor launch flexible and smooth operation, avoiding the system impact to the valve.The entire system is debugged configuration application in laboratory. Through the practice, the results show that the intelligent electric actuator is reasonable and effective. Appling the techniques of variable frequency to the intelligent electric actuator, the system uses the integration of machinery design, the circuits of the system is designed. The test's result shows that the design is reasonable and effective.