Research On Generation Mode And Control System For Urban Rail Doubly-fed Linear Motor

With the development of the urban rail transit system, the linear motor be selected as the drive motor because it have the advantages of small turning radius, smooth motion, good climbing ability and having a broad prospect. The primary and secondary of Doubly-fed linear motor(DFLM) are filling with three-phase windings and electrical can be fed to the stator or rotor in a specific condition. So it has important significance in studying DFLM urban rail transit system. This article is simulation researched on the generation modes of the urban rail transit system and the control strategy of DFLM.Firstly, the basic structure features, operation principle of DFLM are analyzed. according to the basic principle of electrical machine, the DFLM’s mathematical model based on three-phase abc coordinate system is established. The mathematical model based on dq two-phase rotating coordinate system under the condition of constant power is driver. The energy flow of system in different conditions that is analyzed and described the working principle of a four-quadrant converter in detail.Secondly, the formulation of dynamic mathematical model of the DFLM is derived and the simulation model of power system in MATLAB/Simulink is established under the control method of secondary current orientation. According to the speed-control theory of DFLM, the flow of energy of working state including sub-synchronous electric operation, sub-synchronous feedback operation, super-synchronous electric operation, sub-synchronous feedback operation are simulated and verified that system energy flow relationship.Finally, taken the bilateral control of stator current oriented vector and analyzed the control principle of primary current oriented. The simulation model of power system in MATLAB is established under that. At the same time, simulation of the above four working state. Because the synchronous speed of DFLM will change with the stator current frequency therefore, it must control to the stator frequency. Also simulation of the above four working state and compare with the state of fixed frequency. The paper validation of the urban rail transit vehicles that operation between the two stations. The power in the rotor to meet all requirements for electrical equipment.