Design And Implementation Of Electric Valve Actuator Controller

Electric valve actuator is a divice that can servo control the opening of valve, by receiving the external control commands, the divice can drive the motor and reducer transfer power to the valve. The electric valve actuator replaces the traditional pneumatic valve actuator and hydraulic valve actuator gradually, and becoming the mainstream in many fields because of its significant advantage in performance, size and usability. Nowdays, due to the demands of speed and accuracy of the valve opening, the new generation of embedded system based electric valve actuator is becoming popular, which has multi-mode communication, precise regulation performance.This thesis was focused on a formal contract project commissioned by a machinery company in Nantong entitled "a research to valve electric actuator controller ". The writer was responsible for hardware design, embedded application software design, prototype production, function debugging, actual test and calibration of the whole electric valve actuator controller.This thesis studied the valve opening measurement mechanism and technical implementation methods, the valve switch control mode, the Modbus bus technology and 4-20 mA bus technology according to technology contract.This work completed the overall system design, the detailed controller hardware and software design. The embedded real-time operating system RT-Thread was used as the underlying platform for software design, providing the reliability of overall system and support for hardware chips by hardware driver. And the multitasking program written in the application layer is completed. Finally, the prototype passed the laboratory debugging and the test of the first party, implementing all technical functions and control accuracy requirements in the contract. were completed to provide overall system reliability.There are six chapters in this thesis:Chapter Ⅰ introduces the application background and research status of electric valve actuator, raising the main research contents and targets of this thesis.Chapter Ⅱ states the design requirements, analyzed and studied the main technical barriers, presented and discussed the design scheme of the system in detail.Chapter Ⅲ introduces the hardware design and discusses the main hardware function module in detail.Chapter Ⅳ introduces the embedded real-time operating system used by the controller briefly, and introduces main modules and the design method of embedded application software in detail.Chapter Ⅴ debugged and verified the modules of the controller, analyzed the problems occurred during the debugging, and proposed solution for these problems.Chapter Ⅵ is the summary and outlook of the whole work.