Prediction Error Analysis of Finite-Control-Set Model Predictive Current Control for IPMSMs

Abstract

Finite-control-set model predictive current control (FCS-MPCC) has been widely investigated in the field of motor control. When the discrete motor prediction model is not obtained accurately, prediction error often occurs, which can result in improper determinations of optimal voltage vectors and can further affect the control performance of motor systems. However, papers evaluating the motor control performance employing FCS-MPCC rarely consider prediction error and its utilization to weaken the influence of inaccurate prediction model. This paper investigates in depth the prediction error caused by three influencing factors from the perspective of model accuracy-discretization method, prediction stepsize, and parameter mismatch. Firstly, the evaluation index, prediction error, is defined and its formulas considering the above three factors are derived based on interior permanent magnet synchronous motor (IPMSM). Then, the theoretical analysis of prediction error is provided. Finally, experimental results of an IPMSM drive system are presented to verify and complement the theoretical analysis. Both the theoretical analysis and experimental results fully elaborate the prediction error, which can offer practical guidelines for the evaluation and improvement of motor control performance, especially for FCS-MPCC in IPMSM applications.

A Super-Twisting Sliding-Mode Stator Flux Observer for Sensorless Direct Torque and Flux Control of IPMSM

“…To observe the rotor position of IPMSMs easily, the active flux is proposed to transform IPMSMs into virtual nonsalient-pole machines. The d-q axis active flux equation in reference [17] is given as: Transforming (1) to an x-y reference frame and combining the relationship between load angle and torque [31], the voltage equation is found as:…”

“…Interior permanent magnet synchronous motor (IPMSM) has been utilized in wide industrial fields because of its advantages like high torque density, fast response, and low torque ripple [1][2][3]. Direct torque control (DTC) is one of the most popular strategies for ac machines for its fast torque response and strong robustness [4,5].…”

“…RS is the resistance, Ldq are the stator inductances, ωe is the rotor electrical angular velocity, ψf is the rotor flux linkage, δ is the load angle, θe is the rotor electrical position, and θs is the stator flux angle. Transforming (1) to an x-y reference frame and combining the relationship between load angle and torque [31], the voltage equation is found as:…”

Enhancing surface‐mounted permanent magnet synchronous motor drives in steady and transient states through improved MPCC method

“…Although there exist many studies focusing on overcoming these drawbacks, these issues are still open case research. 2,3 In the last decade, great effort is made regarding the model predictive control (MPC) method as an efficient alternative to replace the DTC method. The principles behind MPC on electrical drives are based on the future behavior prediction on control variables corresponding to each one of feasible voltage space vectors (VSVs) where the ones that lead to the best behavior is selected through the cost function.…”

Performance Degradation of Surface PMSMs with Demagnetization Defect under Predictive Current Control

“…Since predictive control is based on a system model, its performance strongly depends on the model parameter accuracy [13][14][15][16], and for PMSMs especially on the rotor flux [17]. High temperatures and currents, operating under strong field-weakening conditions, mechanical stresses, magnet cracks and mechanical imperfections may cause (partial) demagnetization [18][19][20][21].…”