The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform

Feng Jiang - One of the best experts on this subject based on the ideXlab platform.

  • Enhanced Generalized Vector Control Strategy for Torque Ripple Mitigation of IPM-Type Brushless DC Motors
    IEEE Transactions on Power Electronics, 2019
    Co-Authors: Jin Wang, Libing Zhou, Xicai Liu, Feng Jiang
    Abstract:

    Optimal currents with appropriate harmonic components injected into the motor windings can effectively mitigate torque ripple for interior permanent magnet (IPM) type brushless dc motors (BLDCMs). However, existing approaches may fail to accurately inject the optimal currents into motors due to the limited current loop bandwidth. This paper proposes a simple enhanced generalized vector Control strategy to mitigate the torque ripple for IPM-type BLDCMs. With the proposed vector Control strategy, the Control Block Diagram for IPM-type BLDCMs is as simple as that with traditional vector Control for sinusoidal permanent magnet synchronous motors. First, an electromechanical energy conversion voltage (EECV), considering the effects of the non-sinusoidal back-EMF and the rotor salience property, is proposed in αβ -axis. Then, a novel coordinate frame is constructed with the proposed EECV, which is based on the arbitrary reference frame theory. As a result, the currents of IPM-type BLDCMs can be decomposed into two constant components, one being linked to the torque and the other one to the flux linkage. Thus, the bandwidth of current loop with simple proportional integral regulator can be equivalently expanded in the proposed coordinate frame. Finally, comprehensive experiments are conducted in different operation conditions to validate the effectiveness of the proposed vector Control strategy.

Qianggang Wang - One of the best experts on this subject based on the ideXlab platform.

  • Decoupling Control for DC Electric Spring-Based Unbalanced Voltage Suppression in a Bipolar DC Distribution System
    IEEE Transactions on Industrial Electronics, 1
    Co-Authors: Jianquan Liao, Niancheng Zhou, Yuansheng Huang, Qianggang Wang
    Abstract:

    The use of bipolar direct current (dc) distribution systems introduces the possibility of unbalanced voltage (current). This situation increases the voltage deviations and power losses at each node owing to the presence of a neutral line current. This article proposes a method that mitigates the unbalanced voltage caused by constant power loads (CPLs) by dc electric springs (DC–ESs). A linearized model is used in the small-signal analysis of CPLs. On this basis, the coupling relationship between positive and negative pole voltages is analyzed. After DC–ESs are introduced, the positive and negative pole voltages and DC–ES output voltages are found to be closely related, thereby increasing the complexity of the Control system. Therefore, a feedforward decoupling Control Block Diagram is introduced on the basis of the small-signal model analysis of DC–ESs in a single node of the bipolar dc system. The Control system is simplified, and different Control loops can be independently Controlled. Thus, the rapidity and anti-interference performance of the Control system are greatly enhanced. Simulation and experimental results of the unbalanced voltage suppression in the bipolar dc system are used to verify the effectiveness of the proposed scheme.

Denis Royston Towill - One of the best experts on this subject based on the ideXlab platform.

  • Identifying the causes of the bullwhip effect by exploiting Control Block Diagram manipulation with analogical reasoning
    European Journal of Operational Research, 2017
    Co-Authors: Mohamed Mohamed Naim, Virginia L. M. Spiegler, Joakim Wikner, Denis Royston Towill
    Abstract:

    Senior managers when solving problems commonly use analogical reasoning, allowing a current ‘target problem’ situation to be compared to a valid previous experienced ‘source problem’ from which a potential set of ‘candidate solutions’ may be identified. We use a single-echelon of the often-quoted Forrester (1961) production-distribution system as a case ‘target model’ of a complex production and inventory Control system that exhibits bullwhip. Initial analogical reasoning based on ‘surface similarity’ would presuppose a classic Control engineering ‘source model’ consisting of a phase-lag feedback system for which it is difficult to derive the transfer function. Simulation alone would have to be relied on to mitigate the bullwhip effect. By using z-transform Block Diagram manipulation, the model for a single-echelon, consisting of 17 difference equations with five feedback loops is shown to have exact analogy to Burns and Sivazlian’s (1978) second order system that has no feedback. Therefore, this more appropriate ‘source model’ is based on a deeper understanding of the ‘behavioural similarities’ which indicates that the bullwhip effect is not in the case of the ‘target model’ due to feedback Control but due to a first-order derivative, ‘phase advance’, term in the feed forward numerator path. Hence a more appropriate 'candidate solution' can be found via the use of a 'recovery' filter. An interdisciplinary framework for exploiting Control engineering Block Diagram manipulation, utilising analogical reasoning, in a practical setting is presented, as is an example in a contemporary supply chain setting.

Luo De-ron - One of the best experts on this subject based on the ideXlab platform.

Jin Wang - One of the best experts on this subject based on the ideXlab platform.

  • Enhanced Generalized Vector Control Strategy for Torque Ripple Mitigation of IPM-Type Brushless DC Motors
    IEEE Transactions on Power Electronics, 2019
    Co-Authors: Jin Wang, Libing Zhou, Xicai Liu, Feng Jiang
    Abstract:

    Optimal currents with appropriate harmonic components injected into the motor windings can effectively mitigate torque ripple for interior permanent magnet (IPM) type brushless dc motors (BLDCMs). However, existing approaches may fail to accurately inject the optimal currents into motors due to the limited current loop bandwidth. This paper proposes a simple enhanced generalized vector Control strategy to mitigate the torque ripple for IPM-type BLDCMs. With the proposed vector Control strategy, the Control Block Diagram for IPM-type BLDCMs is as simple as that with traditional vector Control for sinusoidal permanent magnet synchronous motors. First, an electromechanical energy conversion voltage (EECV), considering the effects of the non-sinusoidal back-EMF and the rotor salience property, is proposed in αβ -axis. Then, a novel coordinate frame is constructed with the proposed EECV, which is based on the arbitrary reference frame theory. As a result, the currents of IPM-type BLDCMs can be decomposed into two constant components, one being linked to the torque and the other one to the flux linkage. Thus, the bandwidth of current loop with simple proportional integral regulator can be equivalently expanded in the proposed coordinate frame. Finally, comprehensive experiments are conducted in different operation conditions to validate the effectiveness of the proposed vector Control strategy.