Unified direct-flux vector control of induction motor self-commissioning drive with analysis of parameter detuning effects

This paper analyses the detuning effects of machine electrical parameters on the performance of unified direct flux vector control (UDFVC) of induction motor drives. Drive self-commissioning is discussed as a way to estimate parameters for better control performance and accurate torque estimation. The potential of the unification of direct flux and current vector control has been recognized for both synchronous and asynchronous AC motor drives in the literature. This control operates in (d_s, q_s) stator flux coordinates with the stator flux being directly controlled by the d_s axis voltage vector component. Machine torque is controlled using a current controller in q_s-axis. Results for the effects of parameter mismatch on control performance are given. In this work, the detuning problem is overcome by drive self-commissioning which estimates machine parameters at start up through special tests at standstill.