This paper presents a new open-ended winding induction motor (OEWIM) based dual-motor differential fourwheel drive (D4WD) for the electric vehicle (EV). Constant speed operation through cruise control is achieved using direct torque control (DTC) algorithm. The redundant vectors are used in the switching vector selection of the DTC algorithm to achieve balanced battery currents. Fault-tolerant operation of the drive is demonstrated, where the EV will work with full torque even if one of the inverters in rear motor drive or front motor drive or both fail. The dynamic model of the proposed drive is presented. The proposed drive and fault-tolerant operation (FTO) is verified through simulation as per the FTP-75 driving cycle. An experimental prototype of the proposed drive is developed, and the above algorithms are verified experimentally as per the FTP-75 and HFET driving cycles. Both the simulation as well as the experimental results are presented, and these results agree with the theoretical observations. Stable operation of EV for the entire test cycle under normal operation, as well as inverter fault conditions, is demonstrated.

This work sets forth a design paradigm for a permanent-magnet synchronous machine (PMSM) architecture that employs rotational asymmetry to obtain an improved constant power speed range performance and increased torque density. A population-based multi-objective optimization design approach is used to design the new machine topology and compare it to a conventional symmetrical surface mounted PMSM. Results obtained demonstrate that improved performance is attainable with the asymmetrical design. Validation of the results is carried out by means of three dimensional finite element analyses.

Fractional-slot concentrated-winding (FSCW) permanent magnet synchronous machines (PMSMs) have several advantages when compared to other conventional topologies. Design of these motors often rely on the designer's experience, or numerical methods which are time inefficient. This makes them unsuitable for multi-objective optimization design procedure in which a huge design space is adopted, and which have been shown to be effective in finding optimum machine designs. This work introduces a generic multi-objective optimization design framework for a surface mounted (SM) FSCW-PMSM based on a general analytical model that considers various machine aspects such as its geometry, winding configuration, losses, iron temporal flux density levels and drive control. The design procedure is demonstrated to design a surface-mounted (SM) FSCW-PMSM motor with a wide constant power speed range of 5:1. Validation is carried out using Finite Element Analysis (FEA) with good agreement in results. INDEX TERMS Fractional-slot, permanent magnet synchronous machines, concentrated winding, multiobjective optimization design, motor optimization design, FSCW-PMSM.

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For high power electric vehicles (EVs), the drive propulsion based on induction motors are emerging as economical alternatives. Compared to conventional induction motors, the open-end winding induction motor (OEWIM) requires only half the DC bus voltage for the given torque. The EV power train based on dual two-level voltage source inverter (VSI) fed OEWIM with isolated dc sources is used in this research. For uniform state-of-charge (SoC) distribution, the power flow from each isolated source needs to be controlled. A two-stage model predictive direct torque control (MPDTC) scheme is proposed to balance the SoC of batteries by proper selection of the VSI voltage vectors. The proposed MPDTC scheme is free from weighting factor tuning and uses a ranking method to predict the optimal voltage vectors. The superiority of the proposed controller in terms of battery SoC balancing is demonstrated. The performance of the the proposed MPDTC EV drive is verified for the FTP75 and HFET driving cycles under different operating conditions, both by simulation and hardware experimental tests.