Analytical Model And Control Of Transverse Flux Linear Switched Reluctance Motor

Maglev traction system uses the levitation force to keep vehicle suspended to improve speed, but its control is complex; wheel-rail traction system uses wheel and rail for orientation, so its control is simple, but the large downward normal force increases the friction between wheel and rail. Half-Magnetic suspension urban rail transit vehicle can reduce the friction by changing the direction of normal force and the body of vehicle is not out of rail, so its control is not complex.The transverse flux linear switched reluctance motor(TFSLRM) is a new kind of linear motor, which has been researched in recent years. It has the advantages of linear motor and switched reluctance motor, and its flux is vertical to its motion direction. While its magnetic circuit is decoupled from electric circuit, the TFLSRM can be designed flexibly according to the demand, and has modular characteristic. TFLSRM based traction system for Half-Magnetic suspension urban rail transit vehicle has some advantages, such as no end effect, modular design and low cost.According to the magnetic circuit feature for TFLSRM, the mathematic model of the magnetic equivalent circuit is constructed. The air gap permeance in all-position range for a phase cycle is conducted. The mathematical model of the thrust force and normal force, which is not only suitable for the same pole widths of primary side and secondary side, but also for their unequal pole widths, is built. The thrust force and normal force for different pole widths of secondary side and different air gap thicknesses are analyzed by using the proposed mathematic model, and the results show that there are great influence on them when using different pole widths of secondary side or different air gap thicknesses.To realize TFLSRM based traction system for half-magnetic suspension urban rail transit vehicle, that the thrust force and normal force are controlled simultaneously to minimize their ripple is a key problem to be resolved. Based on the analysis of SRM direct torque control, a method is proposed to simultaneously control thrust and normal force of TFLSRM. Simulation results verify that the control method is reasonable and effective.In current practice, position sensors are used to obtain the location information, but the structure of position sensor is complicated and not easy to install, which not only increases the complexity of system structure, but also increases the cost and instability of the system. In this paper, the indirect position control methods for SRM are researched. Based on depth analysis of the improved flux method, the simulation model for sensorless control of TFLSRM is established by MATLAB/SIMULINK and the simulation results prove its effectiveness.At last, TFLSRM based traction system for Half-Magnetic suspension urban rail transit vehicle is still in the development stage, in order to offset the shortage of all-digital simulation platform and verify the control method, the Real-time simulation model of TFSLSRM based on the RT-LAB software platform has been built. Then, the hardware-in-loop model is established and simulation results can verify the control method.