Study On Control System Of Muiti-Power-Terminal Machine

Permanent magnet gear based on magnetic field modulation with high torque transmission density can be a substitute of mechanical gearbox to operate for low speed and high torque applications. When the permanent magnet gear is combined with a permanent magnet brushless machine, the whole system can be used as a motoring or generating component, for marine electric propulsion and wind power generation, etc. Generally, the combined system has two mechanical terminals, therefore, the energy can be converted between the mechanical and electrical terminals, or transmitted between the two mechanical terminals, achieving energy saving and speed adjusting. This thesis mainly focuses on how to control the multi-power-terminal machine effectively to implement the operation of low speed and high torque. Also the characteristics of the permanent magnet gear and the multi-power-terminal machine are studied to implement the transmission of the energy between mechanical and electrical terminals.In this thesis, different kinds of existing structures of the dual-mechanical-terminal machine are compared and the proposed control strategies are analyzed. Then, the topology structure and working principle of the multi-power-terminal machine are studied deeply, with the mathematical models in both the phase reference frame and the synchronous rotating reference frame being derived and verified. Furthermore, different control strategies are proposed for different operating modes and simulation models of the control systems are set up and analyzed in the Simulink environment to verify the effectiveness of the control strategies. In the end, prototype controller is designed and built, and its overall structure and key parts of the hardware and software are introduced in detail. Experiments on different operating modes have been carried out and the test results further validate the effectiveness of the proposed strategies.