Key Technology Research On Variable-speed Pump-control-motor Governing System

Variable-speed pump-control-motor governing technology can promote system efficiency and realize energy-saving as compared with traditional hydraulic governing technology, and gradually get people's attention and is widely used. At the same time, there are also some problems in variable-speed pump-control-motor governing technology, such as low speed stiffness, weak anti load interference ability, weak position tracking ability, etc. The above problems are analyzed and the related solutions are researched in order to promote the technology and enlarge its application scope.Basic form and characteristics of the traditional hydraulic governing circuit and the traditional energy-saving hydraulic circuit are introduced, and the research status at home and abroad of frequency hydraulic technology has been elaborated. The theory analysis about the problems in variable-speed pump-control-motor governing system has been carried out. And the open-loop speed loss compensation method and the closed-loop PID control method are proposed for system speed loss and motor angular displacement control. Simulation model of the system is established in AMESim. The simulation analysis under constant load, variable load and variable speed are carried out in order to testify the compensation method, and the simulation analysis under open-loop control and closed-loop PID control are carried out in order to validate the control effect of motor angular displacement. The measurement and control systems of speed loss compensation and motor angular displacement control based on virtual instrument technology are established, and data acquisition module, data analysis and processing module and data output module are elaborated. The measurement and control systems are applied to the variable-speed pump-control-motor governing system. Then the related experiments of speed loss compensation are carried out under constant load, variable load and variable speed, and the related experiments of motor angular displacement control are carried out under open-loop control and closed-loop PID control.The results of simulation analysis and experiments show that the speed loss compensation method can well realize the speed loss compensation under constant load, variable load and variable speed, and the effect of closed-loop PID control of motor angular displacement is significantly better than that of open-loop control. Figure [86] table [7] reference [58]...