● Techno-fix News ●  
2014-08-18 07:50:45

Design Novel Fuzzy Logic Controller of IPMSM(interior permanent magnet synchronous motor) for Electric Vehicles

University of Science and Technology, Wuhan 43074, Hubei Province, China

The permanent magnets of the interior permanent magnet synchronous motor (IPMSM) are buried in the rotor core.
Due to this kind of geometry, IPMSM has a robust mechanical structure, a low effective air gap, and a rotor saliency. These features allow the IPMSM could run both in constant torque region with greater torque output capability and constant power region with wider speed range. Wide speed range is strongly required in many industry applications such as electric vehicle, spindle drives and so on. In a permanent magnet motor, it is not possible to control directly the magnet flux. The air-gap flux, however, is weakened by the demagnetizing current in the direct axis; this control method is called flux-weakening.
All previous studies based the control algorithm for the IPMSM drive system on accurate parameter model.
However, generally, all of the parameters of the IPMSM are varied as the temperature change. Furthermore, due to the core saturation, the inductances varied depending on the
load condition and current phase . 

The advantages of the proposed FLC have been researched through experiment tests. The complete hardware drive system has been implemented by DSP TMS28335 for a prototype 50 kW motor. The test motor and the prototype EV are with same manufacturer.

 As compared to the conventional FLC, the novel FLC has a faster speed response characteristic in the full operation region. The experiments show that the novel FLC can provide a better torque output capacity in the constant torque region, simultaneously, it can extend the operating speed limit in the constant power region. Moreover, the novel FLC reduced the copper lose because of the current adjuster. The superiority and the effectiveness of the proposed scheme have been proved by the experiments results.