Accurate Torque Control of IPM Machines for ISG Hybrid Vehicle Applications

Ricardo/Chery have been involving in developing ISG (Integrated Starter/Generator) hybrid technologies. The objective of this paper is to summarize our experience in achieving accurate torque control of an IPM machine (Interior Permanent Synchronous Machine) for mild ISG hybrid vehicle applications. This paper focus on presenting the issues including IPM machine development, IPM dq-axis inductance detection method and theoretical background, MTPA (Maximum Torque Per Ampere) control for IPM, flux-weakening control strategy and test results analysis. The proposed torque control has been proved in test with less than 3% torque control inaccuracy.