Study On The Key Technique In Design Of Permanent Magnet Synchronous Motor For Metro

The thesis is devoted to exploiting study on the key technique in design of permanent magnet synchronous motor (PMSM) for metro. Three parts are included as follows:At first, the leakage coefficient of PMSM is accurately calculated by three-dimension finite element method (FEM). The leakage coefficient of PMSM is analyzed with factors change such as rotor structure, permanent magnet size, air-gap length and magnetic bridge size, and summarized the rule of leakage coefficient with structural parameter change. Which is useful for the rotor structure choice of PMSM for metro, as well as the leakage coefficient selection in electromagnetic calculation.ANSOFT is used to calculate the reactance parameters of PMSM in the second part. On the basis of the reactance parameters calculations of many permanent magnet synchronous motors, the change law and influencing factor of the reactance parameters with different rotor structure are analyzed, and the rule of the reactance parameters of PMSM is given. Which is good for selecting appropriate rotor structure, as well as enhancing the characteristics of motor.At last, the research work of PMSM for metro is carried out. The influence of motor type to the thermal load and the effective material peak-value power density is analyzed, and the dimensions of the motor are selected. The influence of different rotor structure to the reluctance torque is analyzed, and given the selection principle of the rotor structure. The influence of air-gap length to the permanent magnet quantity and the togging torque is analyzed, and given the select principle of air-gap length. The requirement for leakage reactance on stator of PMSM supplied by voltage type inverter is analyzed, and some parameters are selected, such as electromagnetic load, slots shape of stator and so on. The common method of enhancing the efficiency is given, such as decreasing the iron loss, copper loss and machine loss. Given some cautions on how to decrease the noise and vibration. From above all, a PMSM for metro isdesigned by field-circuit coupled method, and then the motor is analyzed and calculated by ANSOFT.