Research On Permanent Magnet Synchronous Generator With Rectifier Load Electromagnetic And Thermal Properties

Because the high speed permanent magnet synchronous generator has advantages ofsimple structure, small volume, light weight, high power factor, high efficiency, large overloadcapacity and so on, the motor has been applied widely. Recently, with the development ofHVDC system, the main generator of large-scale power stations can run with rectifier load, asa result of the thermal load of high speed permanent magnet synchronous generator can beimpromed,and the service life and the reliability of the motor are affected directly. So thestudy on the heating and cooling issues of the high speed permanent magnet synchronousgenerator have important significance to the safe operation of the motor and designoptimization.In this paper, a1000kW,6450r/min high-speed permanent magnet synchronous generatorhas been an example to study the electromagnetic properties, loss change and the temperaturedistribution of high-speed permanent magnet synchronous generator under differentconditions.Firstly, by using the electromagnetic simulation software ANSOFT to simulate andcalculate the electromagnetic of the high speed permanent magnet synchronous generator withrectifier load to get the magnetic field distribution, air gap magnetic density, voltage andcurrent of the motor when the genetors run in the steady state operation. Secondly, the loss ofeach part of the motor is calculated, and the loss value of motor is compared and analyzedwhen the motor is under rectifier load and resistive load. The results show that iron loss andthe permanent magnet loss have been increased significantly when the motor is under rectifierload. Finally, the water cooling is selectied because of its special application occasions. Thenthe3D modeling software SOLIDWORK has been used to establish sixth model of the motor.The method of from the outside to cut layered has been used to split the motor with GAMBITto ensure the mesh quality and improve the accuracy of the calculation. The distribution oftemperature field of high speed permanent magnet synchronous generator is calculated by thesoftware of FLUENT to obtain the temperature value of the different part of the motor. Thehighest temperature is160.1℃which appeared in the winding, the temperature of the teeth of the stator and the permanent magnet are higher. By comparing the results, the temperature ofthe motor with rectifier load is higher2℃to15℃than the motor with resistive load.