No abstract

No abstract

Widely used permanent magnet synchronous machines (PMSMs) often show a significant inductance variation near and above the rated current values due to saturation. When the inductances are no longer constant, the model equations have to be modified. This paper proposes new, extended equations, which are as similar as possible to the linearized equations, to make the conversion of existing control schemes to the new approach as easy as possible. In addition, methods to measure the inductances needed for the new PMSM equations are explained together with an efficient implementation of the inductances.

Usually, electrical propulsion vehicles are driven by highly dynamic drive controls. To make this possible, it is important to know electrical parameters such as inductances, flux and stator resistance as exactly as possible. In particular, the ohmic stator resistance Rs changes during operation due to temperature changes. Therefore, it is not possible to achieve a high precision over a wide operating temperature range with an offline measurement of Rs. In this paper, a new identification method for stator resistance is presented and compared to a known method. While the conventional method only works properly at certain operating points, the new method does not have this limitation.Index Terms-adjustable speed drive, control of drive, drive, electrical drive, electrical machine, permanent magnet motor, variable speed drive