The Study On Driver System For Low Floor LRVs

Nowadays, Low floor vehicles is the research focus in the field of rail system. Drive system is the core system and technical difficulties of low-floor light rail vehicles (LF LRV), which is directly related to the vehicle’s traction and guiding. In this thesis, the new technology of electric vehicle motor is used for the research on the independent wheel set of the low floor light rail vehicle. The main research is as follows:Firstly, this paper presents a topological structure that used for low floor vehicles drive system through the structure characteristics and work principle analysis of traditional wheel set steering and the reference of the body suspension driving structure of CRH5. According to the independent wheel set drive system structure of low floor vehicles and combined with new technology of electric vehicle drive system of anti-directional-dual-rotor motor, the new structure of counter rotating motor drive system that used for low floor vehicles had been carried out. Finally, this paper analyzed the structure and the advantage of hub motor drive system that used for low floor vehicles.Secondly, this paper had made a research of the hub motor drive scheme for low-floor LRV. Through the analysis of the specific drive mode of hub motor, chosen the direct drive hub motor as the vehicle driving motor. According to the actual situation of marshalling vehicles and running resistance, the calculation of traction motor power and speed have been finished. The estimate of the basic parameters of the motor could be finished by combining with the installation space and the design principles and requirements of the motor. Through the analysis of the electromagnetic properties of the hub motor, the concentrated fractional slot winding scheme and polar groove fitting optimization scheme had been defined.And then, this paper completed the design and optimization analysis of electromagnetic Scheme of hub motor. Through the RMxprt module of ANSOFT, designed the 2D finite element model, analyzed the 32 pole 36 slot model of air gap magnetic field and the output torque. Through the comparative analysis, got the torque and current of different size of air gap. Finished the the selection of air gap by observing the effect of gas gap to magnetic field and output torque.Finally, this paper analyzed the output torque and three-phase current response curve under the different armature parameters, permanent magnet size and combination scheme of pole slot. Through analyze the influence on the cogging torque of different pole and slot combination and slot opening degree, this paper have made the corresponding optimization to the design scheme of hub motor, and finally the cogging torque of motor was controlled in about 5N-m. Compared with the rated output torque, it accounted for only 0.38%. In determining the final parameters of hub motor, finished the computational analysis of the response characteristics of the motor through the establishment of two-dimensional simulation model of motor, the results prove the rationality of the motor design.