Robust current control for PMSMs using sliding mode control with uncertainties estimation

Robust Speed Control for Permanent Magnet Synchronous Motors Using a Generalized Predictive Controller With a High-Order Terminal Sliding-Mode Observer

“…According to the analysis above, it should be noted that the PMSM usually faces unmodeled, time varying, external disturbances because of the influence of the operating conditions. Therefore, for a high-speed control performance of the PMSM, all the parameter uncertainties and unknown external disturbances must be considered in the controller design [28].…”

“…According to (28), the mechanical angular velocity ω m and the system disturbances f are defined as state variables. The extended state space equation of the sliding-mode observer can be expressed as follows:…”

“…Combining the above equations with (28), and ( 29), we can write the equation for the derivative of the observation error as:…”

“…In [27], a soft-switching sliding-mode observer with a flexible boundary layer was designed using a sinusoidal saturation function to reduce chattering phenomenon. In [28], an adaptive rate was combined with a sliding-mode compensation structure to avoid using a high control gain in the entire control procedure, and the effect of system uncertainties was avoided by estimating the real system uncertainties on-line. In [25], a high-order sliding-mode control compensation approach was proposed to reduce the influence of unmeasured parameters and eliminate chattering.…”