| The electric valve speed controller is a key part of the electric valve actuator. The author consults a lot of information and lucubrates the controller, and then develops a new generation of intelligent electric valve speed controller based on much work. The kind of electric valve speed controller with the cnr~ of microcontroller possses not only the functions of a normal instrument, such as testing, controlling and regulating, but also more intelligence which helps realize the control without contact, the real-time display of all parameters, the diagnosis of fault and the failure protection. Following the principles of safety, reliability, advancement and conveniences, this article makes an over-all design of which the whole control system ( controller with micro-processor and alternating-current power electronic switch) is developed. Besides, this article adopts a series of software-and-hardware measures of protection so as to improve the anti- interference ability of the system. The final result of the experiment indicates that the whole system works accurately and credibility, realizing the expected object. |