Bing Tian

Bio: Bing Tian is an academic researcher from Norwegian University of Science and Technology. The author has contributed to research in topics: Sliding mode control & Synchronous motor. The author has an hindex of 6, co-authored 17 publications receiving 170 citations. Previous affiliations of Bing Tian include Nanjing University of Aeronautics and Astronautics & Harbin Institute of Technology.

Decoupled Modeling and Nonlinear Speed Control for Five-Phase PM Motor Under Single-Phase Open Fault

Abstract: Fault-tolerant control of a five-phase (5Ph) permanent magnet (PM) motor has been recently widely studied, however decoupled modeling under faulty conditions is discussed in less details. In this paper, decoupled model of the 5Ph PM motor under single-phase open fault is investigated and based on the proposed model field oriented control (FOC) is applied to the motor. The proposed model is based on the concept of preserving values of fundamental magnetic motive force (MMF) and back electromotive force (EMF) under single-phase open fault, the same as in healthy case, along with keeping equal torque equation at fundamental rotating space. Nevertheless, the output torque still presents some noises due to third harmonics of air-gap flux and system uncertainties, and to cope with those disturbances, sliding mode control (SMC) is proposed in the speed loop to improve the speed performance. The proposed SMC contains a PI controller and a chattering term, and thus it can be easily tuned. The decoupled model is verified by transient finite element analysis finite element analysis (FEA) and further experiment results are presented to confirm the effectiveness of the proposed control strategy.

Fault-Tolerant Control of a Five-Phase Permanent Magnet Synchronous Motor for Industry Applications

Abstract: The next big change in various industry applications is associated with power dense motors, such as permanent magnet synchronous motors (PMSMs). Utilization of multiphase PMSM can offer an additional fault-tolerant capability to their applications. Combining both advantages, this paper proposes a simple yet robust current control strategy for a five-phase PMSM under normal operation and in a case of a loss of one phase. Traditional linear current controllers successfully applied to reference tracking of a healthy motor may become less efficient during postfault operation due to additional unmodeled dynamics. This paper proposes a modified angular transformation to a special rotating frame in which the postfault permanent magnet flux linkage remains unchanged and the motor model remains decoupled. Following this, a nonlinear current control scheme based on sliding mode control is proposed, which successfully treats model inaccuracies and provides good dynamic performance and tracking accuracy. Feasibility of the proposed control strategy is experimentally validated on a laboratory scale PMSM motor with a digital signal processor/field programmable gate array based drive.

Cancellation of Torque Ripples With FOC Strategy Under Two-Phase Failures of the Five-Phase PM Motor

Abstract: This paper investigates torque ripples cancellation of a five-phase (5Ph) permanent magnet (PM) motor under open fault of two phases, where failure phases are either adjacent or nonadjacent. In recent works, torque ripples cancellation is performed at a stationary frame and postfault current solutions for constant output torque are complicated. To implement field-oriented control (FOC) and carrier-based pulse width modulation, reduced-order Clarke and Park transformations are proposed. With the coordinate transformation, a 5Ph motor model under unbalanced conditions has been decoupled. Along with this, the fundamental torque at the d-q frame also remains the same as the healthy case. However, third harmonic of winding density distribution results in torque ripples. To reduce dependence on mathematical model of torque ripples, sliding mode control is employed to calculate q -axis current reference while keeping constant the rotor speed. Decoupled models corresponding to two types of faults, which are adjacent and nonadjacent open fault, are confirmed by finite element analysis, and effectiveness of proposed torque ripples cancellation method is verified on the 5Ph drive in the laboratory.

Repetitive Control Based Phase Voltage Modulation Amendment for FOC-Based Five-Phase PMSMs Under Single-Phase Open Fault

Abstract: This article investigates the most elementary phase voltage modulation (PVM) for a more generic five-phase permanent magnet synchronous motor drive under a single-phase open fault. Most works on this topic are intended for some specific motor types, and in most cases, it assumes the inverter can still be treated as a linear switching-mode power amplifier. This article figures out that due to an oscillating neutral, the phase voltage is unable to be linearly modulated, which is to say the simplest sinusoidal pulsewidth modulation is problematic to fit a newly developed well-decoupled model under single-phase open fault. To this end, a nonlinear transform incorporating the faulty phase voltage is theoretically proposed, which alleviates the influence of oscillating neutral on PVM, and several approaches to cancel the need for phase voltage sensors are comparatively investigated. Accordingly, the PVM with repetitive control and back electromotive force compensation is put forward to fix the “faulty inverter” in practice. Plausible PVM approaches are tested experimentally, and the superiority of the proposed PVM is confirmed by experimental results.

Freewheeling Current-Based Sensorless Field-Oriented Control of Five-Phase Permanent Magnet Synchronous Motors Under Insulated Gate Bipolar Transistor Failures of a Single Phase

Abstract: Model-based sensorless field-oriented control (FOC) suffers from overparameterization and can be laborious to use for a five-phase permanent magnet synchronous motor On the other hand, insulated gate bipolar transistor (IGBT) frequently fails in an electric drive Under IGBT failure, a freewheeling current is observed, and, above all, it carries the failed phase back electromotive force information Based on this observation, this article presents the design of a brand new sensorless FOC by exploiting the freewheeling current to accommodate both IGBT and position sensor failures, which is expected to further enhance the drive's fault-tolerant capability The mathematical model of this current is first established to provide a theoretical basis and a comprehensive understanding of the presented sensorless FOC By virtue of this model, a second-order generalized integrator with a frequency-locked loop can be used as a simple and elegant way to extract position/speed estimates Experimental results are provided to validate the proposed sensorless FOC philosophy

A Review on Multiphase Drives for Automotive Traction Applications

Abstract: This article attempts to cover the most recent advancements in multiphase drives (MPDs), which are candidates for replacing three-phase drives in electric vehicle (EV) applications. Multiphase machines have distinctive features that arouse many research directions. This article reviews the recent advancements in several aspects such as topology, control, and performance to evaluate the possibility of exploiting them more in EV applications in future. The six-phase drives are extensively covered here because of their inherent structure as a dual three-phase system, which eases the production process. This article presents different topologies used in dual three-phase drives and the modulation techniques used to operate them as well as the status of using MPDs in traction applications industrially and the upcoming trends toward promoting this technology more.

Robust Design Optimization of a Five-Phase PM Hub Motor for Fault-Tolerant Operation Based on Taguchi Method

Abstract: This article investigates the efficient robust design optimization of a five-phase permanent magnet (PM) hub motor for electric vehicles. Besides the requirement of high-performance, like high torque density, low torque ripple and efficiency, fault-tolerant operation capability are also considered in the design optimization. To ensure that the motor performance is not sensitive to the variations of manufacturing tolerances, robust design optimization is employed to the investigated motor. To improve the fault tolerant capability of the motor, the motor performances under fault operation are also considered in the optimization. A Fuzzy-based sequential Taguchi robust optimization method is proposed to improve the comprehensive performance and save computing time. The proposed method is efficient because it holds the advantages of Taguchi method, fuzzy theory, and sequential optimization strategy. The motor performance is improved significantly by using the proposed method. Experimental results verify the accuracy of the model used in this study.

Fault-Tolerant Control of a Five-Phase Permanent Magnet Synchronous Motor for Industry Applications

Abstract: The next big change in various industry applications is associated with power dense motors, such as permanent magnet synchronous motors (PMSMs). Utilization of multiphase PMSM can offer an additional fault-tolerant capability to their applications. Combining both advantages, this paper proposes a simple yet robust current control strategy for a five-phase PMSM under normal operation and in a case of a loss of one phase. Traditional linear current controllers successfully applied to reference tracking of a healthy motor may become less efficient during postfault operation due to additional unmodeled dynamics. This paper proposes a modified angular transformation to a special rotating frame in which the postfault permanent magnet flux linkage remains unchanged and the motor model remains decoupled. Following this, a nonlinear current control scheme based on sliding mode control is proposed, which successfully treats model inaccuracies and provides good dynamic performance and tracking accuracy. Feasibility of the proposed control strategy is experimentally validated on a laboratory scale PMSM motor with a digital signal processor/field programmable gate array based drive.

Electrical and Electronic Technologies in More-Electric Aircraft: A Review

Abstract: This paper presents a review of the electrical and electronic technologies investigated in more-electric aircraft (MEA). In order to change the current situation of low power efficiency, serious pollution, and high operating cost in conventional aircraft, the concept of MEA is proposed. By converting some hydraulic, mechanical, and pneumatic power sources into electrical ones, the overall power efficiency is greatly increased, and more flexible power regulation is achieved. The main components in an MEA power system are electrical machines and power electronics devices. The design and control methods for electrical machines and various topologies and control strategies for power electronic converters have been widely researched. Besides, several studies are carried out regarding energy management strategies that intend to optimize the operation of MEA power distribution systems. Furthermore, it is necessary to investigate the system stability and reliability issues in an MEA, since they are directly related to the safety of passengers. In terms of machine technologies, power electronics techniques, energy management strategies, and the system stability and reliability, a review is carried out for the contributions in the literature to MEA.

Simplified Fault-Tolerant Model Predictive Control for a Five-Phase Permanent-Magnet Motor With Reduced Computation Burden

Abstract: This article proposes a fault-tolerant finite control set model predictive control for a five-phase permanent-magnet (PM) motor drive, which offers reduced computation burden and simplified control model. The virtual voltage vectors synthesized from two basic vectors are used to reduce the computation burden. Meanwhile, the steady-state performance is improved. Combining with a reduced decoupling matrix, the discrete model of the five-phase PM motor before and after fault remains unchanged. So, the reconfiguration of the control structure is minimal. Then, a control set and corresponding switching sequence are proposed, which are very suitable for the real-time system. Finally, the validity of the proposed fault-tolerant control is proved by experiments.