Torque Control of a Highly-Saturated IPMSM Drive Using the Flux Linkage Control Scheme and an Augmented-State-Feedback Controller

Torque control performance is essential in propulsion control systems, especially in automotive applications. Together with torque maximization, it becomes a desirable feature to ensure efficient operation of the drive system. At high power density, the phenomenon of self and cross-saturation occurs in the controlled machine, revealing torque and performance deterioration if not considered. Hence, this article proposes a novel approach for torque control of an interior permanent magnet synchronous motor (IPMSM) based on an augmented state-feedback controller (ASFC) with flux-linkage control. The proposed approach, in contrast to classical PI-based current control systems, allows for simplification of the plant’s mathematical description. As a result, a stationary, linear controller may be designed. The mathematical model of the assumed machine (Toyota Prius 4rd generation) is provided with a torque maximization approach. The ASFC structure and synthesis procedure are discussed in detail. The experimental results indicate excellent torque tracking performance and wide torque control bandwidth of the proposed ASFC.