Voltage feedback based flux-weakening control of IPMSMs with fuzzy-PI controller

Abstract

As the traditional flux-weakening control strategies have some limitations, such as poor parameter robustness, non-ideal dynamic performance in the constant power region and so on, a new control strategy based on the formula-based feedforward control and the voltage feedback control is proposed. In this strategy, the given reference values of the flux-weakening currents are first calculated by the simplified formulas used in feedforward control, improving the processing speed of the controller by reducing the computational complexity. Then the reference value of the d axis current is compensated by the fuzzy-PI feedback controller, avoiding operating point drifts caused by the change or inaccurate of parameters in the actual. On this basis, a switching strategy is proposed to achieve a smooth switching between the constant torque and the constant power operation region. The experimental results show that the proposed control strategy has excellent performances, such as strong robustness to parameter perturbation, ideal dynamic performance in the flux-weakening region, smooth switching between the operation regions and so on.