Asymmetric dual winding three-phase PMSM for fault tolerance of overheat in electric braking system of autonomous vehicle

Abstract

In this paper, an asymmetric dual winding three-phase permanent magnet synchronous motor (PMSM) is proposed for enhancing the fault-tolerance of overheat in autonomous vehicles. A conventional dual winding three-phase motor is divided into two three-phase windings, one for the master part and one for the slave part. It is advantageous to have a redundant system by combining two electric control units (ECU) with one motor instead of two motors. However, when the motor is burned out due to excessive overload driving beyond the motor design value, there is a possibility that no operation can be performed even though there are two ECUs. The proposed dual winding three-phase asymmetric motors are designed differently in the master and slave windings so that the simultaneous burnout of master and slave can be avoided. The coil temperature rise according to the asymmetrical winding design of the motor is estimated by the thermal equivalent circuit method. Also, optimal design for proposed model is conducted using the radial basis function (RBF) and the experimental design method. The optimized proposed asymmetric dual winding three-phase PMSM is applied to the design of motor for electric brake systems of an autonomous vehicle and is verified its usefulness.