Control Method Research And Thermal Analysis Of Electromagnetic Continuously Variable Transmission

As a novel Electric Continuously Variable Transmission, the Electromagnetic Continuously Variable Transmission ( EMCVT ) not only works as a CVT with wide ratio range, but also allows the engine power to be split with an electro-mechanism type in a hybrid vehicle. On the premise of meeting the power requirements, the power flow and brake energy can be controlled to significantly improve vehicle fuel consumption and reduce emissions. In this dissertation, the EMCVT which is independent intellectual property is taken as the study object.The main research work is carried out as follows:Firstly, on the basis of the mathematical model of EMCVT, the basic principle of how the EMCVT optimizes the operation of engine and works as a CVT was studied. The improved direct torque control method based on RBF network used on the SRM module was simulated. For the relative position and speed detection between inner rotor and outer rotor of DRM module, the sensorless control method based on the theory of sliding-mode observer of DRM module is analyzed and simulated.Secondly, the finite element model of EMCVT for temperature field simulation was established. The equivalent thermal model of stator winding and rotor winding is presented to simplify the calculation. The effective thermal conductivity ?e ffof inner and outer air-gap is introduced to solve the complex heat exchanges. ?e ffis the thermal conductivity that a stationary fluid should have to transfer the same amount of heat as the moving air in the air-gap. Then, the stator temperature field and the global temperature field under natural cooling conditions of EMCVT were simulated by FEM software, the temperature distribution of EMCVT and temperature rise scope of each part were discussed.Then, the research on the cooling system of the EMCVT prototype is performed. According to the simulation conditions, EMCVT temperature field with a cooling system was simulated to verify the cooling effect. The influences of the various parameters for temperature field was discussed based on the simulation, such as EMCVT bed-plate material, fan speed, cooling bar height, the cooling oil temperature and cooling channel diameter. The results of simulation provides a reference for choosing the parameters of EMCVT. Lastly, the feasibility of sensorless control method used on DRM module was proved by ACSM1 controller. Then, some preliminary experiments was done to test the no-load characteristic of DRM module.