Intelligent Variable Frequency Electric Actuators

Electric actuator is a very important equipment in valve control, which plays an important roles in pipe net of liquid control, such as water, gas (stream) etc. Electric actuator which is powered by electric energy and uses motor to control the opening percent of valve, have been used comprehensively in industry due to the excellence suach as highly precision, the adjustable output torque, the variable control method, the intellectualized adjustment and managerment etc.A prototype of Electric Actuator with Smart Frequency Conversion Control, which realizes the smart control of valve and the networks communication based on CAN bus, is designed and developed.SVPWM is adopted to realize the motor with frequency conversion control. In this paper the digital calculate principle and arithmetic based on DSP is introduced particularly. The main circuit loop adopted IPM as inversion part, the main loop circuit of inversion based on IPM is discussed particulary and the circuit parameter is reasearched. The power loss simulation analysis of IPM, which uses the working condition of IPM as simulation parameter, is used to confirm the safety operating area. The real-time, open loop speed modulation motor control is realized in 5～100Hz by experiment test.The low power consumption design, which achievees the requir of using battery by the experiment and circuit optimize, is based on TI's ultralow-power microcontroller--MSP430F1232.The interface of field bus is designed based on CAN Bus standard. By using extension of CAN controller interface, the CAN bus link of data link layer and physic layer is realized and the assign method of CAN bus identifier is defined simply.