This paper proposed a novel multi objective optimization design method for switched reluctance motor (SRM) on low speed electric vehicles (EVs). According to the indexes of low speed EV propulsion system and the large torque ripple of SRM, six objectives of geometric parameters optimization of SRM are given, which are maximum speed, accelerate time, maximum climbing gradient, energy usage ratio and torque ripple factor. The rated parameters of the driving motor are given based on the basic parameters of the low speed EVs. Based on the engineering design method, the dimension range of SRM under the rated parameter range is confirmed. The dynamic simulation model of low speed pure EVs propulsion system is built in MATLAB/Simulink based on the finite element model of SRM and the vehicle balance equation. Then a multi-objective optimization design of the geometric parameters of SRM is carried out by Taguchi-Chicken Swarm Optimization (Taguchi-CSO) algorithm. The correctness of the finite element model is verified, and the accuracy of the multi objective optimization is verified by the dynamic simulation results and the low speed EV experiment.

Instantaneous torque control and average torque control (ATC) strategies of switched reluctance machine (SRM) are comparatively investigated to select appropriate control mode for the application of SRM in electric vehicles (EVs). Three novel methods are put forward to optimise ATC for meeting the performance requirements of EVs. On‐line estimator is designed to estimate the average torque of SRM in real‐time and improve the steady‐state torque precision. Current chopping control‐angle position control hybrid crossover control is proposed to widen the adjustable speed range and improve the process smoothness of SRM in consideration of acceleration and deceleration. Turn‐on and turn‐off angles of SRM are optimised by generic algorithm to enhance driving efficiency and reduce torque ripple. At last, the three proposed control methods are validated by simulations and experiments.

Through comprehensive study for the power converters that have emerged previously for switched reluctance machine (SRM) drive system, this paper proposes an evaluation approach to determine the suitability of these converters for using in SRM-based electric vehicle (EV) drive system. This evaluation reflects the relative differences of these converters in terms of their cost as well as their capability to offer best technical performance for the drive system of EVs. From technical viewpoint, four factors are considered as follow: the converter efficiency, the converter reliability, the capability of the converter to reduce torque ripple, and to increase power productivity. A benchmark consists of number of converter characteristics is identified. The operation of the converters is analyzed to determine, in quantitative way, their fulfillments to these characteristics. Expressions for the evaluation factors are proposed in terms of the converters’ characteristics. Accordingly, the converters are relatively scored to reflect their differences in cost as well as in technical impact on the SRM drive system. The results provide useful indication for trade-off between gaining some of advantages and losing others for EV applications. In addition, they identify of potentials for optimization based on the cost and the technical performance of different SRM converters.

With the rapid development of wind power generation technology worldwide, the influence of intermittent and fluctuating characteristics of wind power generation on the microgrid and load is attracting a lot of attention along with its increasing penetration. Aimed at solving the problem that only wind speed variation is considered in the generation plan of traditional small-scale wind power generation applications, this paper presents a set of control schemes for the switched reluctance generator based small-scale wind power generation system with the integrated energy storage system. Considering the possibility of off-grid operation of small-scale wind power generation systems in the areas where the grid is weak or even uncovered, the proposed control scheme increases the consideration of dynamic changes in load and energy storage unit. To improve the utilization efficiency of small-scale wind power generation, a step control scheme is proposed combining maximum power tracking control with power balance control. The two-stage inverter is established to generate ac 110V/60Hz outputs by voltage closed-loop control in boost circuit of front stage and PI control in the inverter circuit of the second stage. Finally, the effectiveness of the proposed control schemes is verified experimentally.

To overcome the disadvantages of traditional switched reluctance machine (SRM) with moderate power/torque density and high torque ripple, this article proposes a novel double-stator SRM (DSSRM) with the inner and outer stators both adopting U-shaped segmental stator structure. By optimizing the polarity distribution of the inner and outer stator magnetic fields, the inner and outer stator magnetic fields are decoupled. Then, the relationships of torque ripple coefficient with the mechanical offset angles of the inner and outer rotor teeth are investigated. To optimize the mechanical offset angle and reduce the torque ripple of the motor, the initial design method is proposed, and five main parameters of the machine are optimized by the finite-element analysis. Then, the static magnetic characteristics and dynamic performance of this novel machine are simulated and analyzed. Finally, a 16/18/18/16 DSSRM is prototyped to validate the above simulation and theoretical analysis.

In this paper, a novel reliability assessment scheme is presented to achieve the optimal selection of control strategies for switched reluctance machine system from the perspective of reliability. To begin with, a combination model of k-out-of-n:G model and Markov model is proposed to lower the complexity and enhance the accuracy of system-level reliability assessment. As for the component-level reliability assessment, the three-dimensional coupled thermal circuit model of power converter is built to achieve the precise and fast prediction of junction temperature that is necessary for calculation of failure rate. Then the static and dynamic reliability analyses are carried out under voltage chopping control (VCC), current chopping control (CCC), and angle position control (APC) strategies, which indicates that the implementation scope of the APC strategy should be broadened. Compared with the VCC strategy, the CCC strategy is strongly recommended even if current sensors boost the extra failure rate. Besides, the increase in redundancy levels on power converter is certified as the most powerful measure for reliability enhancement of the SRM system and the most cost-effective redundancy level can also be quantitatively obtained. The experiments of fault-tolerance capability and thermal stress indirectly verify the validity of reliability analysis.