Study On PMSM Of Widen The Constant Power Adjust Speed Control Range For Electric Vehicle

With the rapid development of automobile industry, more and more cars wereproduced. The issue of air pollution is getting worse. The most direct way to solve thecurrent problem of automobile exhaust pollution is to develop new energy vehicles. As theenergy conversion tool of electric vehicle, the motor has been widely studied. Due to thehigh efficiency, low torque ripple, high power density and dynamic performance,permanent magnet synchronous motor (PMSM) has been widely used in the electricvehicle industry. However, since the limited of motor controller and motor itself, thehighest speed of traditional PMSM is greatly restricted, make the motor can’t meet thespeed acquirements of EV drive system.To solve this problem, this paper based on the mathematical model of PMSM and theconstant power adjust speed control theory, focused on the design of motor, researched aneffectively way to improve the constant power adjust speed range of PMSM. Purposed amethod to make the PMSM can satisfy the acquirements of EV. The method is increasingthe direct axis reactance and reducing the EMF during the designing step. This papermainly studied about the impact of the external characteristics when the size of permanentmagnet which inserted in the rotor changed.In the first of all, this paper focus on the PMSM used in EV, with the current ideas ofconstant power control and the mathematical model of PMSM, analyzed the influence ofthe width and the thickness of the PM on the output torque and constant power adjustspeed control range of PMSM. And then the paper simulated how the motor performancewould be influenced by V-shape permanent magnet parameters such as the placement ofthe PM, the magnetizing length of PM, and the width of magnetic bridge by using theAnsoft Maxwell2D. Comprehensive simulation data and laboratory experience to designthe most suitable motor for the project later. At last, manufacturing a prototype andmeasured the performance of the prototype under different working conditions.Experimental results indicated that the conclusion of theoretical analysis is correct. Thehighest speed of PMSM is2.9times as against rated speed.