Qualitative approach to electromechanical energy conversion: Reinventing the art of design in adjustable speed drives

In recent years, considerable research efforts have been devoted to the development of power electronics for enhanced control of electric drives. Traditional analysis and control of a drive is often based on a generalized system model, wherein a relationship between the average torque and phase current is established analytically. However effects of the applied control scheme on the resultant radial force components and geometrical distribution of forces are not provided by these models. This paper presents a novel field reconstruction approach towards the accurate modeling of the drive which includes an analytical expression describing the electromagnetic behavior of the machine. This is an ideal technique for the numerical analysis and performance evaluation of an electric drive from an electromagnetic perspective. Since finite element analysis (FEA) only needs to be performed once, the cost and time involved in generating the desired results are dramatically reduced This paper uses a 3-phase PMSM to illustrate the proof of principle. However the concept can be extended to any machine type with a known geometry.