The energy utilization ratio (ER) quantifies the utilization of a Switched Reluctance Motor (SRM). Calculation of ER of an SRM can be different from other motors as it has highly nonlinear operating characteristics and uses an asymmetric bridge converter. In this paper, the concept of ER for SRMs has been explained first and then a computation methodology is presented based on the co-energy and stored energy in the magnetic system. The magnetic stored and co-energy are evaluated in ANSYS Maxwell for the static characterization of the motor. These magnetic energy quantities are computed under the dynamic operation of the SRM drive from the area under the flux linkage-current curve to compute the energy utilization. An experimental correlation is performed for validating the proposed ER computation methodology in SRM drives. Finally, the components of the energy utilization ratio are applied to determine the control objectives of a switched reluctance motor drive to improve the electromagnetic performance. Utilizing the energy utilization ratio components in the optimization of the phase turn on and turn off angles of an SRM helps to achieve a single optimization objective to improve the average torque, energy utilization and torque ripple performance, and they can be used in multi-objective optimization, as well.

Smart grids offer improved environmental performance along with increased resilience; however, they are susceptible to a wide range of cyber attacks owing to the wide communication network deployed. In this paper, two cyber attack models are proposed based on bus voltage magnitude and angle which can be realized through available cyber attacks. Simulations are performed on IEEE 9 bus test system to compute steady state voltage stability limit i.e. L index to analyse the impact of proposed cyber attack models at each bus using Siemens PSS/E and MATLAB softwares. Further, a cyber attack constant (CAC) is proposed to mislead the system state data which an attacker may utilize. The results of above work reveal that the proposed cyber attack models may initiate false corrective actions by energy management center (EMC) operator. Thus, the idea of proposed work can support the EMC operator for intelligent corrective actions during cyber attacks in the smart electric grid.

Electric motors constitute a critical component of an electric vehicle powertrain. An improved motor design can help improve the overall performance of the drivetrain of an electric vehicle making it more compact and power dense. In this article, the electromagnetic torque output of a double V-shaped traction IPMSM is maximized by geometry optimization, while considering overall material cost minimization as the second objective. A robust and flexible parametric model of the IPMSM is developed in ANSYS Maxwell 2D. Various parameters are defined in the rotor and stator geometries to perform an effective multi-objective parametric design optimization. Advanced sensitivity analysis, surrogate modeling, and optimization capabilities of ANSYS optiSlang software are leveraged in the optimization. Furthermore, a demagnetization analysis is performed to evaluate the robustness of the optimized design. At high-speed operation, a rotor core is usually subject to higher deformation due to the high centrifugal force. Thus, rotor stresses are reduced in the optimized design by shaping the flux barriers around the permanent magnets. This enables high structural integrity of the optimized design for high-speed operation along with the improved electromagnetic performance. The multi-physics design approach proposed in this article provides the capability to design and optimize an IPMSM geometry for performance and cost, which are essential objectives to achieve in an electrified powertrain development. Moreover, consideration of rotor stress at high operating speeds extends the applicability of the proposed design approach to high-power, high-speed electric propulsion applications.

This letter proposes a concept to discriminate an electrical fault from a cyber attack in the modern power system. A cyber attack factor is introduced which may mislead the bus voltage stability virtually at load buses. The proposed cyber attack models are validated by executing multiple cyber attacks at a time on Western system coordinating council (WSCC) 9 bus test power system by using Siemens PSS/E and MATLAB softwares. Further, the impact of electrical fault and cyber attack on the WSCC 9 bus test power systems voltage stability has been analysed to develop a discrimination algorithm in reference to chosen load index. Despite its simplicity, the proposed discrimination algorithm is robust, accurate and quite suitable to develop intelligent measures for mal-operations against cyber attacks in the smart electric grid.

Switched Reluctance Motors (SRMs) are a promising motor type to reduce the cost of electrified vehicle propulsion systems in the near future. This study presents the design and analysis of a 12/8 SRM for a 48 V, 30 kW Full Hybrid Electric Ve-hicle (FHEV) propulsion application. The proposed design aims to meet the performance requirements of the target Permanent Magnet Synchronous Motor (PMSM) with an SRM that does not require rare-earth permanent magnets. This work addresses the design challenges of the SRM of this application, especially in high-speed operating region. The performance of the SRM drive has been optimized for the entire torque-speed curve using a weighted single objective genetic algorithm based optimization in MATLAB/Simulink. The efficacy of the SRM design is validated through simulation studies for various operating points of the targeted application.

The benefits of utilizing Switched Reluctance Motor (SRM) drives in traction applications can be realized fully by improving the electromagnetic performance of the machine in the generating mode of operation. This is because the generating capability of an SRM drive could be utilized for regenerative braking and also for the machine to generate power for the vehicle while the engine is in operation. In this paper, a current profiling-based control strategy is proposed to reduce the torque ripple in an SRM drive in the generating mode. The reference current profile is determined using a multi-step computation method to minimize torque ripple and maximize the average torque. The reference current profile is derived based on the reference torque command by utilizing the torque–current–angle look up table. The flux linkage characteristics of the SRM are considered when deriving the phase reference current profile. Then, the performance of the proposed profiling method, analytical linear and cubic torque sharing functions (TSFs), and the average torque optimization scheme are compared using simulation results. Finally, an experimental correlation is performed to validate the efficacy of the proposed control scheme.