Reduction of torque and flux ripples in direct torque control for three‐level open‐end winding PMSM drive

Abstract

The direct torque control (DTC) of permanent magnet synchronous motor (PMSM) drives is a noticeable practice in industrial applications due to its quick dynamic performance. However, due to the presence of hysteresis controllers and inaccurate switching tables especially for the multilevel fed DTC drives are facing higher ripples in torque and flux response. An improved DTC for three-level open-end winding PMSM drive is proposed in this article and features reduction of flux and torque ripples. The torque and flux performances of the PMSM are directly controlled by the calculated reference voltage vector in the stationary reference frame. The voltage vector tables are proposed based on the length of the voltage space vectors and the actual voltage vector nearer to the calculated reference voltage vector is selected so that the minimum ripples exist in flux and torque responses. The steady-state and dynamic conditions of the proposed DTC method are verified in the real-time experiment and also compared with the conventional DTC as well as the recently developed control methods.

THD Reduction for Permanent Magnet Synchronous Motor Using Simulated Annealing

“…A DTC-PMSM with fuzzy comparator for PMSM in low speed applications is stated in [1][2][3][4][5] to minimize the variation in flux and torque. Speed, flux and torque variables in the stationary reference frame are controlled by the optimum control theory.…”

Development of enhanced direct torque control for surface‐mounted permanent magnet synchronous motor drive operation

“…Here, it should be noticed that the calculation process of reference stator flux vector ($$\Psi _s^*$$) is independent of stator inductance parameter (unlike existing DTC [18]). Finally, in the process of reference VV generation, the reference stator flux vector ($$\Psi _s^*$$) is applied without any parameter dependency.…”

“…Finally, in the process of reference VV generation, the reference stator flux vector ($$\Psi _s^*$$) is applied without any parameter dependency. This results in robust control of S‐PMSM drive in parameter uncertainty condition, and provides optimal flux and torque response with less ripples when compared with existing DTC [18].…”

“…This results in poor steady state response (high ripples in torque and flux), along with rise in inverter switching frequency. Whereas, in [18] (Section 4), DTC performs through reference VV generation (). In (), the substituted reference stator flux vector ($$\Psi _s^*$$) calculations are motor parameter dependent ().…”

Unified coordinated control strategy for two parallel inverters TPOW-PMSM system

“…The voltage vector distribution of the two parallel inverters is equal to that of the three-level inverters, and there is no neutral voltage fluctuation problem [5]. As a new kind of topology, its application in various fields has been explored by many scholars [6,7]. However, as a new structure that has the function of a fault-tolerant topology, where its three-phase current can be controlled separately, a TPOW-PMSM driven by two parallel inverters has not been studies a great deal in the EV research field.…”