Abstract:In this paper

the engineering approximate methods of maximum torque per ample control (MTPAC) in a kind of interior permanent magnet synchronous motor (IPMSM) with high saliency were studied to improve the real time performance and control precision.According to the mathematical model of IPMSM in d-q axises

the distribution of d/q axis current under MTPAC was derived via extremum principle. For the correspondence between the d /q axis components of stator current and the eletromagnetic torque

a new polynomial fitting arithmetic that could divide curves automatically was proposed. Several quadratic curves were connected to approximate the whole relation curves under MTPAC. Less amount of calculation and higher accuracy were leaded to by the arithmetic than that of using single high order polynomial.Both the flowchart and the simulation results in Matlab were given.The results showed that this method was simple and feasible. In some degree

it had an instructive and directive significance to actual object practice.