Torque Superposition Compensation Fault-Tolerant Control for Dual Three-Phase PMSM with an Inverter Single-Leg Open-Circuit Fault

Abstract

Dual three-phase permanent-magnet synchronous motors (PMSM) have wide applications in electric vehicles due to advantages such as excellent control performance and outstanding fault tolerance capability. However, present fault-tolerant control of inverter single-leg open-circuit faults cannot make full use of each phase winding of the motor, which limits the torque-production capability. This paper proposes a torque superposition compensation (TSC) control which can minimize the stator copper losses while increasing the torque-production capability. The phase winding originally connected to the faulty inverter leg is then linked to the DC-link mid-point. Thus, the winding in the faulty phase can be utilized to generate an additional torque. The symmetric dual three-phase windings torque model and the asymmetric five-phase windings compensation torque model for Ud/2 voltage level are constructed according to the torque superposition, respectively. Then, the three-subplane decomposition transformation matrix for the post-fault dual three-phase PMSM is derived, and the decoupling model in the d-q subplane is constructed, which achieves the optimal enhancement of the torque-production capability. The simulation results verify the effectiveness of the proposed TSC fault-tolerant control.

Identification of Parameters and States in PMSMs

“…A straightforward technique called scalar control offers good speed control but subpar torque management. More sophisticated techniques that offer accurate speed and torque control include vector control and field-oriented control [12]. Field-oriented control depends on the principle of changing the positioning of the motor's magnetic field, whereas vector control is focused on the principles of decoupling the torque and flux components of the motor.…”

PMSM Field-Oriented Control with Independent Speed and Flux Controllers for Continuous Operation under Open-Circuit Fault at Light Load Conditions

“…Discussed in [14] is an open-circuit fault tolerance control of dual three-phase PMSM. The torque superposition compensation control (TSC) was proposed to increase the capability of torque production and reduce copper losses.…”