Deadbeat control based on a multipurpose disturbance observer for permanent magnet synchronous motors

Abstract

Robustness against parameter mismatches and position-sensorless operation are two important research topics for permanent magnet synchronous motor (PMSM) drives. In this paper, a sliding mode disturbance observer (SMDO) is proposed to achieve either of two functions for different application environments: 1) if a position sensor is equipped, accurate current regulation can be achieved by deadbeat predictive current control (DBPC) despite mismatched motor parameters; 2) if the position sensor is not equipped but with a good estimation of motor parameters, the observer can serve as a back electromotive force (EMF) estimator. On this basis, the rotor position can be extracted for positionsensorless control. Usually, low-pass filter is required to suppress high frequency noises in conventional sliding mode observer. This inevitably leads to phase delay in the estimation, which cannot be directly used for disturbance compensation. While in the proposed method, a complex coefficient filter is inherently embedded, which can provide accurate estimation without phase or magnitude error. Experimental results obtained from a 2.4 kW PMSM drive platform indicate that high performance current control can be achieved with good robustness for position sensor based operation. And, rotor position can be accurately estimated with good steady and dynamic performance for position-sensorless operation.

Current-Controller-Free Self-Commissioning Scheme for Deadbeat Predictive Control in Parametric Uncertain SPMSM

“…The switching frequency of MPC is not fixed [4], [6], and large harmonic ripples may occur. By contrast, the output voltage of DBPC is synthesized by a modulator with fixed switching frequency, thus the torque ripples are smaller [7], [8]. So it is favorable to adopt DBPC in applications that with requirements of low torque ripples.…”

“…On one hand, analysis of the influence of parameter mismatch on DBPC has been conducted in [5], [7] and [8]. One accepted conclusion is that the Ld and Lq mismatches will cause current steady state error (CSSE) or even make the DBPC unstable.…”

Predictive Current Trajectory Control for PMSM at Voltage Limit

“…Different observation methods are used to improve the robustness, e.g. extend kalman filter (EKF) [22], sliding-mode observer (SMO) [23], extended states observer (ESO) [24]. Moving horizon estimator (MHE) is a new method compared with the methods mentioned above.…”

Online Current Loop Tuning for Permanent Magnet Synchronous Servo Motor Drives with Deadbeat Current Control

“…The discretized PI controller directly designed in the z-domain has been proposed in [3,4]; however, limited improvement in the current loop bandwidth was achieved and current overshoots were persistent. To eliminate the influences of the time delay, schemes based on the predictive current control [5][6][7][8][9][10][11] and deadbeat current control [12][13][14][15][16][17] have been proposed. The predictive current controller generates the optimal voltage vector by minimizing a specific cost function.…”

“…However, the effect caused by the parameter mismatch can be treated as a disturbance to the current controller. To compensate for this disturbance, the compensation voltage, which was obtained through the disturbance observer in [12,17] and through adaptive control in [25], is added to the current loop. Despite their effectiveness, the schemes in [17,25] involve a complex design procedure to achieve satisfactory performance.…”