In order to enhance the transient performance of aircraft high voltage DC(HVDC)generation system with wound rotor synchronous machine(WRSM)under a wide speed range,the nonlinear PI multi-loop control strategy is propo...In order to enhance the transient performance of aircraft high voltage DC(HVDC)generation system with wound rotor synchronous machine(WRSM)under a wide speed range,the nonlinear PI multi-loop control strategy is proposed in this paper.Traditional voltage control method is hard to achieve the dynamic performance requirements of the HVDC generation system under a wide speed range,so the nonlinear PI parameter adjustment,load current feedback and speed feedback are added to the voltage and excitation current double loop control.The transfer function of the HVDC generation system is derived,and the relationship between speed,load current and PI parameters is obtained.The PI parameters corresponding to the load at certain speed are used to shorten the adjusting time when the load suddenly changes.The dynamic responses in transient processes are analyzed by experiment.The results illustrate that the WRSM HVDC generator system with this method has better dynamic performance.展开更多
This study proposes a novel asymmetric rotor pole design for wound field synchronous machines(WFSMs),which can achieve high saliency ratio and also low torque ripple.The key point is the optimal design of the asymmetr...This study proposes a novel asymmetric rotor pole design for wound field synchronous machines(WFSMs),which can achieve high saliency ratio and also low torque ripple.The key point is the optimal design of the asymmetric rotor pole with the inverse-cosine-shaped(ICS)plus reverse 3rd harmonic shaping.The asymmetric rotor pole can help to improve the average output torque by enhancing the saliency ratio.The reverse 3rd harmonic shaping on the rotor pole surface is mainly used to reduce the torque ripple.To certify the effectivity of the proposed design,three-phase 54-slot/6-pole 4.7kW WFSMs with uniform air gap and with non-uniform air gap shaped by the ICS plus optimum reverse 3rd harmonic are utilized as the basic model and referenced model for comparison.For the referenced model,the optimum amplitude of reverse 3rd harmonic is preferred as 1/6.Finally,all electromagnetic characteristics of the investigated machines are predicted by the finite-element method(FEM).The highest saliency ratio and comparatively low torque ripple have been verified.展开更多
In this paper,a new dual-stator brushless doubly-fed induction machine with a staggered dual cage rotor is proposed,with emphasis on the general interconnection rule of the conductor bars for the staggered dual cage r...In this paper,a new dual-stator brushless doubly-fed induction machine with a staggered dual cage rotor is proposed,with emphasis on the general interconnection rule of the conductor bars for the staggered dual cage rotor.Since the squirrel cage rotor offers the merits of robustness,reliable structure,high slot filling factor,and low rotor resistance comparing to the wound rotor,it is introduced to the dual-stator brushless doubly-fed induction machine to solve the problems of high copper loss and unreliable rotor structure for the dual-stator brushless doubly-fed induction machine with a wound rotor.The originality of this article is to investigate the interconnection rule of conductor bars between the inner and outer cages.The constraint condition that is supposed to be satisfied is deduced by using the rotating magneto-motive force theory,based on which diverse slot/pole combinations are investigated.The performance comparison between the existing and proposed machines is conducted.Finally,a prototype is designed and fabricated.The experimental results verify the effectiveness of the proposed topology.展开更多
The brushless doubly-fed machine(BDFM)has been widely used due to its advantages of robustness,reliable operation,ease of maintenance,adjustable power factor,small converter capacity and low cost.BDFM is attractive fo...The brushless doubly-fed machine(BDFM)has been widely used due to its advantages of robustness,reliable operation,ease of maintenance,adjustable power factor,small converter capacity and low cost.BDFM is attractive for use in many applications such as variable frequency speed regulation systems and variable speed constant frequency generation systems.Hence,there is a rapidly growing interest in design and control of BDFM.In this paper,the origin and development of BDFM are reviewed,the structural characteristics of BDFM are discussed at length,the principles of operation and design are analyzed,and the different control methods used for BDFM are overviewed and compared in detail.Finally,challenges and opportunities of BDFM are concluded.展开更多
基金supported by funded by"Ye Qisun"Joint Foundation Project supported by the State Key Program of National Natural Science Foundation of China under Award U2141223.
文摘In order to enhance the transient performance of aircraft high voltage DC(HVDC)generation system with wound rotor synchronous machine(WRSM)under a wide speed range,the nonlinear PI multi-loop control strategy is proposed in this paper.Traditional voltage control method is hard to achieve the dynamic performance requirements of the HVDC generation system under a wide speed range,so the nonlinear PI parameter adjustment,load current feedback and speed feedback are added to the voltage and excitation current double loop control.The transfer function of the HVDC generation system is derived,and the relationship between speed,load current and PI parameters is obtained.The PI parameters corresponding to the load at certain speed are used to shorten the adjusting time when the load suddenly changes.The dynamic responses in transient processes are analyzed by experiment.The results illustrate that the WRSM HVDC generator system with this method has better dynamic performance.
文摘This study proposes a novel asymmetric rotor pole design for wound field synchronous machines(WFSMs),which can achieve high saliency ratio and also low torque ripple.The key point is the optimal design of the asymmetric rotor pole with the inverse-cosine-shaped(ICS)plus reverse 3rd harmonic shaping.The asymmetric rotor pole can help to improve the average output torque by enhancing the saliency ratio.The reverse 3rd harmonic shaping on the rotor pole surface is mainly used to reduce the torque ripple.To certify the effectivity of the proposed design,three-phase 54-slot/6-pole 4.7kW WFSMs with uniform air gap and with non-uniform air gap shaped by the ICS plus optimum reverse 3rd harmonic are utilized as the basic model and referenced model for comparison.For the referenced model,the optimum amplitude of reverse 3rd harmonic is preferred as 1/6.Finally,all electromagnetic characteristics of the investigated machines are predicted by the finite-element method(FEM).The highest saliency ratio and comparatively low torque ripple have been verified.
基金supported by the National Natural Science Foundation of China (Grant No.61973073)。
文摘In this paper,a new dual-stator brushless doubly-fed induction machine with a staggered dual cage rotor is proposed,with emphasis on the general interconnection rule of the conductor bars for the staggered dual cage rotor.Since the squirrel cage rotor offers the merits of robustness,reliable structure,high slot filling factor,and low rotor resistance comparing to the wound rotor,it is introduced to the dual-stator brushless doubly-fed induction machine to solve the problems of high copper loss and unreliable rotor structure for the dual-stator brushless doubly-fed induction machine with a wound rotor.The originality of this article is to investigate the interconnection rule of conductor bars between the inner and outer cages.The constraint condition that is supposed to be satisfied is deduced by using the rotating magneto-motive force theory,based on which diverse slot/pole combinations are investigated.The performance comparison between the existing and proposed machines is conducted.Finally,a prototype is designed and fabricated.The experimental results verify the effectiveness of the proposed topology.
基金National Natural Science Foundation of China(51537007)PhD Start-up Fund of Natural Science Foundation of Liaoning Province,China(20141072).
文摘The brushless doubly-fed machine(BDFM)has been widely used due to its advantages of robustness,reliable operation,ease of maintenance,adjustable power factor,small converter capacity and low cost.BDFM is attractive for use in many applications such as variable frequency speed regulation systems and variable speed constant frequency generation systems.Hence,there is a rapidly growing interest in design and control of BDFM.In this paper,the origin and development of BDFM are reviewed,the structural characteristics of BDFM are discussed at length,the principles of operation and design are analyzed,and the different control methods used for BDFM are overviewed and compared in detail.Finally,challenges and opportunities of BDFM are concluded.