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Interior Permanent Magnet Synchronous Motor (IPMSM) is widely used in Electric Vehicle (EV) applications. In EV, the electric motor is characterized by high power density, high speed, and light weight. The high-speed, high-power density, fault tolerance capability of the IPMSM make it a suitable candidate for such an EV system. The performance improvement of IPMSM during design is highly desirable. With the application of soft magnetic alloy material Hiperco 50A in place of traditional steel material, the performance of the IPMSM can be greatly improved. Compared to the steel material, the Hiperco 50A provides high power density, low core loss and improved efficiency. With this focus, this paper investigates the application of soft magnetic alloy material (Hiperco 50A) in 150 kW power IPMSM.

Numerical simulation of lithium-ion batteries (LIB) has become extremely vital in the understanding of thermal behaviour of LIBs to develop active and passive battery thermal management systems. The LIB is popular in consumer electronics. Beyond consumer electronics, the LIB is also growing in popularity for the automotive applications such as hybrid electric vehicles (HEVs) and battery electric vehicles (BEVs) due to its high energy density, high voltage, and low self-discharge rate. High amount of heat generally gets developed during charge and discharge of LIB based on the c-rate at which it is being discharged or charged. Hence, there should be a mechanism to understand the thermal behaviour of these cells. Thus, in this paper a numerical procedure has been developed to model electrochemical-thermal behaviour of commercially available 21700 Li-ion cells. NewmanP2D approach is used to arrive at electrochemistry performance of Li-ion cell and pack.

This paper presents the design of Interior Permanent Magnet Synchronous motor (IPMSM) using Soft Magnetic Composite (SMC) material for Electric Vehicle (EV) applications. In EV, the electric motor is characterized by high power density, high torque, low weight and cost efficient. The high torque, high power to weight ratio and high mechanical strength Synchronous Motor along with the SMC structures will make it suitable candidate for such an EV application. With this focus the new SMC material Somaloy 3P is proposed as a motor core material. The SMC material is made up of iron powder particle coated with an electrically insulated layer which gives a unique 3D flux property. This material provides low eddy current losses because of high material resistance. The benefits of Somaloy 3P material for design of electric motor are compact, high performance, weight reduction and cost efficient.

Electric motor whine is one of the main noise sources of hybrid and electric vehicles. This paper describes a comprehensive analytical and experimental investigation of permanent magnetic electric motor NVH designs focusing on the contribution from torque ripple (TR) and radial forces (RF). A design-of-experiment method is adopted to design and build candidate motors with (i) high TR and high RF; (ii) high TR and low RF; (iii) low TR and high RF and (iv) low TR and low RF. Four prototype motors are built and tested on motor fixtures to measure dynamic stator forces in radial, tangential and axial directions, track dominant motor orders, and estimate motor Operational Deflection Shapes (ODS). Finite-element based electromagnetic and NVH analyses are performed and correlated to test data. Both tests and analyses confirm reducing TR and RF improves motor NVH performance at dominant pole pass orders.

Battery Electric Vehicles (BEVs) are becoming more competitive day by day to achieve maximum peak power and energy requirement. This poses challenges to the design of Thermal Interface Material (TIM) which maintains the cell temperature and ensure retention of cell and prevent electrolyte leak under different crash loads. TIM can be in the form of adhesives, gels, gap fillers. In this paper, TIM is considered as structural, and requires design balance with respect to thermal and mechanical requirements. Improving structural strength of TIM will have negative impact on its thermal conductivity; hence due care needs to be taken to determine optimal strength that meets both structural and thermal performance. During various crash conditions, due to large inertial force of cell and module assembly, TIM is undertaking significant loads on tensile and shear directions. LS-DYNA® is used as simulation solver for performing crash loading conditions and evaluate structural integrity of TIM.

Pulse Width Modulation or PWM has been widely used in traction motor control for electric propulsion systems. The associated switching noise has become one of the major NVH concerns of electric vehicles (EVs). This paper presents a multi-disciplinary study to analyze and validate current ripple induced switching noise for EV applications. First, the root cause of the switching noise is identified as high frequency ripple components superimposed on the sinusoidal three-phase current waveforms, due to PWM switching. Measured phase currents correlate well with predictions based on an analytical method. Next, the realistic ripple currents are utilized to predict the electro-magnetic dynamic forces at both the motor pole pass orders and the switching frequency plus its harmonics. Special care is taken to ensure sufficient time step resolution to capture the ripple forces at varying motor speeds.

Electric motor noise mitigation is a challenge in electric vehicles (EVs) due to the lack of engine masking noise. The design of the electric motor mounting configuration to the motor housing has significant impacts on the radiated noise of the drive unit. The stator can be bolted or interference-fit with the housing. A bolted stator creates motor whine and vibration excited by the motor torque ripple at certain torsional resonance frequencies. A stator with interference fit configuration stiffens the motor housing and pushes resonances to a higher frequency range, where masking noise levels are higher at faster vehicle speeds. However, this comes with additional cost and manufacturing process and may impact motor efficiency due to high stress on stators. In this paper, a thin sheet metal NVH ring is developed as a tunable stiffness device between the stator and the motor housing. It is pre-compressed and provides additional torsional rigidity to mitigate torsional excitations.