A novel driving method for switched reluctance motor with standard full bridge inverter

This paper proposes a new driving method for a switched reluctance motor (SRM) by using a standard full bridge. The windings in the SRM are connected in series to build a ring structure, where a controllable DC source is inserted. Based on the new structure, the theoretical analysis and calculation are made to determine the control parameters. Besides three-phase SRM, the new idea can also be applied to the SRMs with four and five phases. The new driving method is compared with the conventional method by simulation. The results show that with the new method, the ripple of torque and speed in the SRM reduces. The influence of the proposed method on the power rating and losses is then analyzed. The validation is also made to verify the application of the new method and the difference between the conventional driving method and the proposed method. The measured results match the simulated results well

Field Oriented Control of Multiphase Drives with Passive Fault-Tolerance

Multiphase machines provide continuous operation of the drive with no additional hardware in the event of one or more open-phase faults. This faulttolerant capability is highly appreciated by industry for security and economic reasons. However, the steadystate post-fault operation has only been feasible in previous works after the fault localization and control reconfiguration. Even though this is done at the software stage, the obligation to identify the faulty phases and store the modifications for every fault scenario adds further complexity. This work reveals that this software reconfiguration can be avoided if the field-oriented control (FOC) strategy is designed to satisfactorily handle pre- and post-fault situations. Experimental results confirm the capability to obtain suitable postfault operation without fault localization and control reconfiguration, thus achieving a passive/natural fault tolerance.Ministerio de Ciencia, Innovación y Universidades RTI2018-096151-B-I0

Performance Comparison of Fault-Tolerant Three-Phase Induction Motor Drives Considering Current and Voltage Limits

With the increasing demand for electric vehicles, reliability in motor drives is an issue of growing importance. Over the years, various fault-tolerant three-phase motor drive topologies have been introduced and their performances have been investigated. Evaluation of the postfault power of a fault-tolerant drive should take into account both the postfault torque and speed, which depend on both the postfault current and voltage limits. Nevertheless, the postfault motor voltage limits are usually omitted from discussion. Furthermore, current limit in induction motor drive is not as direct as that in permanent magnet motor drive, due to the presence of the flux current. In this paper, the performances of available fault-tolerant three-phase induction motor drives have been reinvestigated, taking into account the impact of not just currents, but also voltage limits for both the inverter and machine. By deriving the postfault machine voltage equations, the effects of machine parameters and operating point on the voltage limit and hence the speed limit are explained. Depending on the topology, the motor may be able to run above the rated speed to gain extra power. The analysis is verified through experiment results on a 1 kW induction machine for four different fault-tolerant drive topologies