Studies On Energy-closed AC Asynchronous Electrical Dynamometer System

The gearbox, one kind of transmission machines is a pivotal facility of automobile and engineering machine, and it is widely used. It directly affects the performance of dynamics, economy and reliability of automobile and engineering machine. Recently, with the development of the automobile industry, the request of performance test of gearbox is increasingly higher. Aiming at the performance test of gearbox, this paper studies on the energy-closed AC asynchronous electrical dynamometer and its control system. Based on the detailed analysis of operating principle of this system, this paper deeply researches the operating state of dynamometer, its mathematic model, the basic theory of vector control, the design of hardware, the strategy of control and its implementation of software. And the development of the control system of the electrical dynamometer is also completed.The operating principle and the relations among the main torques of electrical dynamometer system (EDS) are discussed, then the running state and conditions of the system function are analyzed. Based on the theory of vector control theory of AC asynchronous motor, this paper discusses the detail principle of vector controlled variable speed system. The different model and motion equations of electrical dynamometer are constructed through coordinate transformation. The torque and flux decoupling control are realized, As a result, the dynamic response performance of dynamometer system is guaranteed. Through the analysis of dynamic control process, a speed and torque closed-loop control strategy is proposed that adopts the fuzzy control as the core, and the corresponding structure design and implementation are discussed. Then the conception of road test emulation on chassiss dynamometer is introduced, and the emulation of the road resistance is also studied, At last, the road test in lab is performed and the experimented results show that the efficiency of the performance test of gearbox.In the part of the hardware design of control system, the paper analyzes the principle of composing and its basic structure, gives the detailed circuit of the input signal detection, the output of control signal and the system safeguard which takes industry control computer as the core, the detection and process circuit such as torque, rotating speed, current, voltage signal as the base, and takes the inverters as...