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Flow Field Improvement by Bowed Stator Stages in a Compressor with Different Axial Gaps Under Near Stall Condition 被引量:4
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作者 陆华伟 陈浮 +2 位作者 宋彦萍 万继林 王仲奇 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期215-222,共8页
The outlet flow fields of a low-speed repeating-stage compressor with bowed stator stages are measured with five-hole probe under the near stall condition when the rotor/stator axial gap varies. The performances of th... The outlet flow fields of a low-speed repeating-stage compressor with bowed stator stages are measured with five-hole probe under the near stall condition when the rotor/stator axial gap varies. The performances of the straight stator stages are investigated and compared to those of the bowed stator stages. The results show that using bowed stator stages could alleviate the flow separation at both upper and low corners of the suction surface and the endwalls, and decrease the losses along the flow passage as well as the outlet flow angle. As the rotor/stator axial gap decreases, although the diffusion capacity of the compressor increases obviously, the outlet flow field in the straight stator stages deteriorates quickly. By contrast, little changes occur in the bowed stator stages, indicating that as the rotor/stator axial gap decreases, improved performance is achieved in the bowed stator stages. 展开更多
关键词 COMPRESSOR bowed stator rotor/stator axial gap near stall condition corner separation
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LOW COST IMPLEMENTATION OF SPEED SENSORLESS INDUCTION MOTOR CONTROL USING STATOR FLUX ORIENTATION 被引量:2
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作者 李勇 黄文新 胡育文 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第1期34-40,共7页
The control platform of the induction motor (IM) with low costs is developed by using DSP MC56F8013 with a good performance/price rtaio. The control algorithm for the speed sensorless IM is studied based on the stat... The control platform of the induction motor (IM) with low costs is developed by using DSP MC56F8013 with a good performance/price rtaio. The control algorithm for the speed sensorless IM is studied based on the stator flux orientation (SFO). The algorithm structure is simple to be implemented and cannot be influenced by motor parameters, The improved stator flux estimation is used to compensate errors caused by the low pass filter (LPF). A new speed regulator is designed to ensure the system working with the maximal torque in the transient state. The system simulation and the prototype experiment are made. Results show that the con- trol system has good dynamic and static performance. 展开更多
关键词 induction motor stator flux orientation speed sensorless control algorithm
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浅析基于车载以太网的BACK-TO-BACK电路板设计 被引量:1
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作者 刘旭 郑子健 +1 位作者 张殿明 崔根群 《汽车电器》 2018年第2期24-26,共3页
经过充分调查研究车载以太网的理论基础和国内外发展情况,以当前车辆行业市场需求为背景,对比当前车载网络技术优势和不足,设计一种用于验证车载以太网实际连通性能和真实传输速率的电路板。该方案基于恩智浦公司的TJA1100收发器芯片,... 经过充分调查研究车载以太网的理论基础和国内外发展情况,以当前车辆行业市场需求为背景,对比当前车载网络技术优势和不足,设计一种用于验证车载以太网实际连通性能和真实传输速率的电路板。该方案基于恩智浦公司的TJA1100收发器芯片,利用其可在Reserves MII模式下工作的优势,进行BACK-TO-BACK电路板硬件设计,重点围绕TJA1100进行硬件环境搭建。 展开更多
关键词 以太网 back-to-back电路板 连通性 传输速率
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短定子磁浮列车基于悬浮间隙实现测速和定位的算法仿真及应用
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作者 汤彪 朱跃欧 +2 位作者 蒋毅 乔若辉 吴定鼎 《湖南工业大学学报》 2025年第1期51-56,共6页
短定子磁浮列车测速和定位技术实现方式与传统轮轨不同,目前有多种技术实现方式,但都需要在磁浮列车上设置测速和定位设备或系统,且与悬浮控制系统相互独立,但悬浮控制系统对速度信号和位置信号又有一定的依赖性。因此,设计了一种基于... 短定子磁浮列车测速和定位技术实现方式与传统轮轨不同,目前有多种技术实现方式,但都需要在磁浮列车上设置测速和定位设备或系统,且与悬浮控制系统相互独立,但悬浮控制系统对速度信号和位置信号又有一定的依赖性。因此,设计了一种基于悬浮间隙实现测速和定位的算法,并通过仿真达到算法设计预期目的,最后通过编程将算法嵌入磁浮列车的悬浮控制系统硬件平台,实现测速和定位的算法应用,测速和定位信号完全集成于悬浮控制系统中,摆脱悬浮控制系统对外置测速定位系统的依赖,提升磁浮列车在轨道交通市场的竞争力。 展开更多
关键词 短定子磁浮列车 悬浮间隙 测速 定位 算法仿真
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Experimental Study of Stator Clocking Effects in an Axial Compressor 被引量:5
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作者 陈浮 顾忠华 +1 位作者 陆华伟 王仲奇 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第4期278-285,共8页
This paper is focused on the experimental study of the effects of stator clocking on the performance of a low-speed repeating stage axial compressor with compound-lean stators as well as the one with conventional stat... This paper is focused on the experimental study of the effects of stator clocking on the performance of a low-speed repeating stage axial compressor with compound-lean stators as well as the one with conventional stators (the baseline) for comparison. The experimental results show that as the clocking positions vary, the upstream stator wake enters the following passage at different circumferential positions, and then mixes with the local fluid in the following passage. This is the main reason for the variation of the compressor performance resulted from the stator clocking effects. The variation of the compressor performance due to the clocking effect is less pronounced for the compressor with compound-lean stators than with the baseline. At a certain clocking position, the efficiency of the compressor with compound-lean stators is increased in comparison with that of the baseline, especially on small mass flow rate conditions, e.g., 0.7% at design condition and 3.5% at near-surge condition in this case. The maximum 1.22% and the minimum 0.07% increases in efficiency on design condition are obtained through the combined effects of the stator compound-lean and the stator clocking in this case. 展开更多
关键词 compressor performance stator clocking compound-lean stator wake interaction
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THE RESONANCES OF PARAMETRIC VIBRATION WITH FORCED VIBRATION OF THE STATOR SYSTEM OF HYDROELECTRIC-GENERATOR STIMULATED BY ELECTROMAGNETISM 被引量:2
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作者 Qiu Jiajun Li Wenlan Yang Zhian 《Acta Mechanica Solida Sinica》 SCIE EI 1999年第1期63-73,共11页
The resonances of parametric vibration with forced vibration isanalyzed, the bifurca- tion equation of the system is obtained andthe singularity analysis is made. Some of the laws and phe- nomenaare revealed. The tran... The resonances of parametric vibration with forced vibration isanalyzed, the bifurca- tion equation of the system is obtained andthe singularity analysis is made. Some of the laws and phe- nomenaare revealed. The transition variety and bifurcation diagram of thephysical parameteric plane are given. the results can be used inengineering. 展开更多
关键词 hydroelectric-generator stator system stimulated by electromagnetism
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Visual study on the characteristics of liquid and droplet in a novel rotor-stator reactor 被引量:2
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作者 Yubin Wang Jun Li +3 位作者 Yang Jin Ming Chen Yan Cao Jianhong Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2643-2652,共10页
Rotor–stator reactor(RSR), an efficient mass transfer enhancer, has been applied in many fields. However,the hydrodynamic characteristics of liquid flow in RSR are still a mystery despite they are fundamental for the... Rotor–stator reactor(RSR), an efficient mass transfer enhancer, has been applied in many fields. However,the hydrodynamic characteristics of liquid flow in RSR are still a mystery despite they are fundamental for the mass transfer performance and processing capacity. In view of the above, this paper studies the liquid–liquid flow and liquid holdup in RSR under various conditions with a high-speed camera. The paper firstly demonstrates two flow patterns and liquid holdup patterns that we obtained from our experiment and then presents in succession a flow pattern and a liquid holdup criterion for the transition of film flow to filament flow and complete filling to incomplete filling. It is found that experimental parameters, including rotor–stator distance, rotational speed and volume flow rate exert great influence on the average droplet diameter and size distribution. Besides, by comparison and contrast, we also find that the experimental values match well with our previous predicted calculations of the average diameter, and the relation between the average diameter and the mean energy dissipation rate. 展开更多
关键词 Rotor–stator reactor Liquid–liquid flow pattern LIQUID HOLDUP DROPLET size distribution AVERAGE DROPLET DIAMETER
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Stator-Flux Oriented Continuous Control of Torque in Induction Motors 被引量:4
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作者 Hong-ming Xie Yi Ruan Bo-shi Chen 《Advances in Manufacturing》 2000年第1期49-53,共5页
This paper analyzes dynamic equivalent circuit of induction motor and the relationship among inner fluxes, then presents a direct stator flux oriented continuous torque control (DSFOCTC) scheme of induction motor , wh... This paper analyzes dynamic equivalent circuit of induction motor and the relationship among inner fluxes, then presents a direct stator flux oriented continuous torque control (DSFOCTC) scheme of induction motor , which uses stator current vector control instead of voltage vector control. As a combination of direct torque control (DTC) and flux oriented vector control, it achieves round stator flux and continuous dynamic torque control resulting in less torque ripple than that in DTC. It reduces the dependence on rotor parameters, and is especially insensitive to rotor resistance. Finally, an induction motor speed control system incorporating this novel scheme is given and checked by simulation. 展开更多
关键词 flux accelerate method stator flux oriented rotor flux oriented DTC
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Enhanced control of DFIG-used back-to-back PWM VSC under unbalanced grid voltage conditions 被引量:20
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作者 HU Jia-bing HE Yi-kang NIAN Heng 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1330-1339,共10页
This paper presents a unified positive-and negative-sequence dual-dq dynamic model of wind-turbine driven doubly-fed induction generator(DFIG) under unbalanced grid voltage conditions. Strategies for enhanced control ... This paper presents a unified positive-and negative-sequence dual-dq dynamic model of wind-turbine driven doubly-fed induction generator(DFIG) under unbalanced grid voltage conditions. Strategies for enhanced control and operation of a DFIG-used back-to-back(BTB) PWM voltage source converter(VSC) are proposed. The modified control design for the grid-side converter in the stationary αβ frames diminishes the amplitude of DC-link voltage ripples of twice the grid frequency,and the two proposed control targets for the rotor-side converter are alternatively achieved,which,as a result,improve the fault-ride through(FRT) capability of the DFIG based wind power generation systems during unbalanced network supply. A complete unbalanced control scheme with both grid-and rotor-side converters included is designed. Finally,simulation was carried out on a 1.5 MW wind-turbine driven DFIG system and the validity of the developed unified model and the feasibility of the proposed control strategies are all confirmed by the simulated results. 展开更多
关键词 Unbalanced grid voltage Doubly-fed induction generator (DFIG) back-to-back (BTB) Fault-ride through (FRT) Voltage source converter (VSC)
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Application of Dual-blade Stator to Low-speed Ratio Performance Improvement of Torque Converters 被引量:7
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作者 WU Guangqiang WANG Lijun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期293-300,共8页
With application of the lock-up clutch in the torque converter(TC), fuel economy is not much determined by its high-speed ratio transmission efficiency. As a benefit, more researches are focused on its low-speed rat... With application of the lock-up clutch in the torque converter(TC), fuel economy is not much determined by its high-speed ratio transmission efficiency. As a benefit, more researches are focused on its low-speed ratio performance so as to improve vehicle gradeability and launching acceleration performance. According to the results of computational fluid dynamics(CFD) analysis, hydrodynamic loss inside the stator cascade accounts for 42% of the total energy loss at stalling speed ratio. It is found that upstream flow with large impingement angle results in boundary layer separation at the leading edge, which aggregates hydrodynamic loss and decreases circular flow rate dramatically at low-speed ratio. In this paper, a dual-blade stator is proposed to suppress the boundary layer separation, which is parameterized by using the non-uniform rational B spline(NURBS) method. The mean camber line and blade profile curve are expressed by a three control points quadratic open NURBS and a cubic closed one respectively. The key design parameters included the slot width and suction side shape of the primary blade are analyzed. The most effective slot width is found to be between 4% and 8% chord length, and the boundary layer separation can be suppressed completely by decreasing distribution of momentum moment at the primary blade and adding it to the leading edge of the secondary blade. As a result, circular flow rate and impeller torque capacity is increased by 17.9% and 9.6% respectively at stalling speed ratio, meanwhile, low-speed ratio efficiency is also improved. Maximum efficiency at high-speed ratio decreases by 0.5%, which can be ignored as the work of lock-up clutch. This research focuses on using the dual-blade stator to optimize low-speed ratio performance of the TC, which is benefit to vehicle power performance. 展开更多
关键词 torque converter dual-blade stator boundary layer separation non-uniform rational B spline
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OPTIMAL DESIGN FOR STATOR OF THREE-DOF ULTRASONIC MOTOR 被引量:4
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作者 ZHAOChun-sheng LIZhi-rong HUANGWei-qing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第2期88-93,共6页
A 3-DOF ultrasonic motor with a cylinder-shaped stator and a spherical rotor is developed. The motor provides 3-DOF rotation around x, y, and z-axes implemented by two second order bending modes with orthogonality an... A 3-DOF ultrasonic motor with a cylinder-shaped stator and a spherical rotor is developed. The motor provides 3-DOF rotation around x, y, and z-axes implemented by two second order bending modes with orthogonality and one first order longitudinal mode of the stator. The three modes must satisfy some conditions. In our previous research, in order to satisfy these conditions, a parameter fitting design method is used. However, it is an experiential design method with low efficiency and costs much time, sometimes it even cannot find a desired solution. This paper puts forward an optimal design method for the stator. Based on the method, an optimization program is developed in MATLAB environment. Using the program, a new prototype of 3-DOF ultrasonic motor is designed. Its stator has diameter of 20 mm, height of 67 mm, and mass of 157 g. Experimental results show that the measured stators′ modal frequencies and modal shapes are in good consistent agreement with the results obtained by the optimal design program. 展开更多
关键词 ultrasonic motor stator optimum design
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Parameter Modeling and Kinematical Simulation for Rotor and Stator of Screw Pump 被引量:1
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作者 倪益华 吴健 过海 《Journal of Donghua University(English Edition)》 EI CAS 2013年第1期38-43,共6页
The research object used in the dissertation was screw pump, which was widely applied in engineering field. The analysis of end face profile formation was completed on its main working components, i.e., rotor and stat... The research object used in the dissertation was screw pump, which was widely applied in engineering field. The analysis of end face profile formation was completed on its main working components, i.e., rotor and stator. With the purpose of finding optimal parameters to improve the efficiency of screw pump design, the key technologies involved in the parametric modeling of rotor and stator were analyzed. The three-dimensional (3D) design software SolidWorks was used for the secondary development and parametric modeling of rotor and stator. After that the simulation models of different kinds of screw pumps were established based on the cycloid type, variation coefficient, and screw head number. Finally the COSMOSMotion was used to analyze the motion characteristics on the equidistant line of rotor, including velocity and acceleration. This design and modeling method has been used in screw pump enterprises for design and development, laying the foundation for finite element analysis and further optimization of screw pump. 展开更多
关键词 PARAMETER modeling SIMULATION ROTOR stator SCREW PUMP
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Calculation for electromagnetic torque of double-stator-permanent magnet synchronous motor 被引量:1
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作者 柴凤 朱春波 程树康 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第2期58-61,共4页
Presents the mathematic model built for double stator permanent magnet synchronous motors through a brief analysis of their future development, and the equations established for calculation of their torques, and the d... Presents the mathematic model built for double stator permanent magnet synchronous motors through a brief analysis of their future development, and the equations established for calculation of their torques, and the development of prototypes, and discusses the comparison of the motor under development with the conventional motors with the same volume, stator structure, and magnet shape, and concludes the motor under development is one of the ways to improve the performance/volume ratio of motors. 展开更多
关键词 double stator electromagnetic TORQUE SYNCHRONOUS motor
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MATCH-MODE METHOD AND ITS NUMERICAL SIMULATION FOR ROTOR-STATOR INTERACTION SOURCE MODES AND PROPAGATION MODES IN AN ANNULAR DUCT WITH MULTI-TREATMENTS 被引量:1
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作者 吕亚东 余永祥 +1 位作者 胡宗安 孙晓峰 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1999年第2期3-12,共10页
The suppressing design of the engine nacelle in an aircraft can benefit from the development of the prediction system for the sound fields in engine ducts which includes the prediction of the source generation and tha... The suppressing design of the engine nacelle in an aircraft can benefit from the development of the prediction system for the sound fields in engine ducts which includes the prediction of the source generation and that of sound propagation in ducts. First, the acoustic match mode principle between the source modes of rotor stator interaction noise and the propagation modes is presented in this paper. Second, by utilizing this principle, the theoretical prediction method for rotor stator interaction noise generation and its propagation and attenuation in an annular duct with multi treatments is developed. That means that the prediction of sound propagation and attenuation in the segmented ducts might no longer completely depend on the in duct mode measurements, and the investigation on the sound propagation and attenuation in ducts can be accomplished not only by acoustic mode measurement, but also by making use of the source prediction to determine the source modes excited by rotor stator interaction. The effects of fan speed, blade/vane numbers, axial spacing between rotor and stator on the in duct sound attenuation and generated sound power level before and after ducts (also including the sound power level of blade passing frequency and its harmonics at the inlet of ducts) have been numerically calculated by using this prediction method. The reliability of this prediction method is verified by reasonable agreement between the predicted results with measured results in references. By analyzing the results of calculating cases, some reference criteria are provided for the engineering design of the suppressing engine nacelle. 展开更多
关键词 aeroacoustics rotor stator interaction noise sound propagation in ducts match mode
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Feasibility of a New Ironless-stator Axial Flux Permanent Magnet Machine for Aircraft Electric Propulsion Application 被引量:13
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作者 Zhuoran Zhang Weiwei Geng +1 位作者 Ye Liu Chen Wang 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第1期30-38,共9页
With the development of aviation electrification,higher demands for electrical machines are put forward in aircraft electric propulsion systems.The aircraft electric propulsion requirements and propulsion motor featur... With the development of aviation electrification,higher demands for electrical machines are put forward in aircraft electric propulsion systems.The aircraft electric propulsion requirements and propulsion motor features are analyzed in this paper.Comparing with conventional PM machines,ironless stator axial flux permanent magnet(AFPM)machine topologies with Litz wire windings allow designs with higher compactness,lightness and efficiency,which are suitable for high-frequency and high-power density applications.Based on the motor requirements and constraints of aircraft electric propulsion systems,this paper investigates a high-power 1 MW multi-stack ironless stator AFPM machine,which is composed of four 250kW modular motors by stacking in axial.The design guidelines and special attentions are presented,in term of electromagnetic,thermal,and mechanical performance for the high-frequency coils and Halbach-array PM rotor.Finally,an ironless stator AFPM motor is manufactured,tested and evaluated with the consideration of cost and processing cycle.The results show that the output power is up to 53.8kW with 95%efficiency at 9000r/min at this stage.The proposed ironless stator AFPM machine with oil immersed forced cooling proves to be a favorable candidate for application in electric aircraft as propulsion motors. 展开更多
关键词 Axial flux machine electric aircraft electric propulsion ironless stator permanent magnet machine oil cooling.
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An Improved Stator Flux Observation Method of Permanent Magnet Synchronous Motor 被引量:1
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作者 Guangjing Su Hongmei Li +1 位作者 Ying Dai Zheng Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第6期90-96,共7页
The stator flux and electromagnetic torque observation is the basis of direct torque controlled permanent magnet synchronous motor( PMSM) drive system. However,the traditional stator flux observer based on voltage mod... The stator flux and electromagnetic torque observation is the basis of direct torque controlled permanent magnet synchronous motor( PMSM) drive system. However,the traditional stator flux observer based on voltage model is affected by integral initial values and integral drift,that based on current model is affected by the parameters of PMSM,so a new stator flux observation method is proposed based on an improved secondorder generalized integrator( SOGI). Compared to the stator flux observation method based on the conventional SOGI,the proposed method can not only overcome the influence of integral initial values and integral drift,but also completely eliminate the DC offset's influence. Therefore,the observation accuracy of stator flux is further improved. The simulation and experimental results both show that the proposed method has a higher stator flux and electromagnetic torque observation precision. 展开更多
关键词 permanent magnet synchronous motor direct torque control second-order generalized integrator stator flux observation electromagnetic torque observation
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GENERATOR VIBRATION FAULT DIAGNOSIS METHOD BASED ON ROTOR VIBRATION AND STATOR WINDING PARALLEL BRANCHES CIRCULATING CURRENT CHARACTERISTICS 被引量:2
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作者 Wan Shuting Li Heming +1 位作者 Li Yonggang Tang Guiji 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期592-596,共5页
Rotor vibration characteristics are first analyzed, which are that the rotor vibration of fundamental frequency will increase due to rotor winding inter-turn short circuit fault, air-gap dynamic eccentricity fault, or... Rotor vibration characteristics are first analyzed, which are that the rotor vibration of fundamental frequency will increase due to rotor winding inter-turn short circuit fault, air-gap dynamic eccentricity fault, or imbalance fault, and the vibration of the second frequency will increase when the air-gap static eccentricity fault occurs. Next, the characteristics of the stator winding parallel branches circulating current are analyzed, which are that the second harmonics circulating current will increase when the rotor winding inter-turn short circuit fault occurs, and the fundamental circulating current will increase when the air-gap eccentricity fault occurs, neither being strongly affected by the imbalance fault. Considering the differences of the rotor vibration and circulating current characteristics caused by different rotor faults, a method of generator vibration fault diagnosis, based on rotor vibration and circulating current characteristics, is developed. Finally, the rotor vibration and circulating current of a type SDF-9 generator is measured in the laboratory to verify the theoretical analysis presented above. 展开更多
关键词 Generator Fault diagnosis Rotor vibration characteristic stator winding parallel branches circulating current
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A 4H-SiC merged P–I–N Schottky with floating back-to-back diode 被引量:2
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作者 Wei-Zhong Chen Hai-Feng Qin +3 位作者 Feng Xu Li-Xiang Wang Yi Huang Zheng-Sheng Han 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期660-664,共5页
A novel 4 H-Si C merged P–I–N Schottky(MPS)with floating back-to-back diode(FBD),named FBD-MPS,is proposed and investigated by the Sentaurus technology computer-aided design(TCAD)and analytical model.The FBD feature... A novel 4 H-Si C merged P–I–N Schottky(MPS)with floating back-to-back diode(FBD),named FBD-MPS,is proposed and investigated by the Sentaurus technology computer-aided design(TCAD)and analytical model.The FBD features a trench oxide and floating P-shield,which is inserted between the P+/N-(PN)junction and Schottky junction to eliminate the shorted anode effect.The FBD is formed by the N-drift/P-shield/N-drift and it separates the PN and Schottky active region independently.The FBD reduces not only the Vturn to suppress the snapback effect but also the Von at bipolar operation.The results show that the snapback can be completely eliminated,and the maximum electric field(Emax)is shifted from the Schottky junction to the FBD in the breakdown state. 展开更多
关键词 4H-SIC merged P-I-N Schottky(MPS) snapback effect turnover voltage floating back-to-back diode(FBD)
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Squeezed Back-to-Back Correlation of D^0~0 in Relativistic Heavy-Ion Collisions 被引量:1
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作者 Ai-Geng Yang Yong Zhang +2 位作者 Luan Cheng Hao Sun Wei-Ning Zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期25-28,共4页
We investigate the squeezed back-to-back correlation(BBC) of D^0~0 in relativistic heavy-ion collisions, using the in-medium mass modification calculated with a self-energy in hot pion gas and the source space-time ... We investigate the squeezed back-to-back correlation(BBC) of D^0~0 in relativistic heavy-ion collisions, using the in-medium mass modification calculated with a self-energy in hot pion gas and the source space-time distributions provided by the viscous hydrodynamic code VISH2+1. It is found that the squeezed BBC of D^0~0 is significant in peripheral Au+Au collisions at the relativistic heavy ion collider energy. A possible way to detect the squeezed BBC in an experiment is presented. 展开更多
关键词 in Relativistic Heavy-Ion Collisions BBC Squeezed back-to-back Correlation of D~0
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Influence of Inner/Outer Stator Pole Ratio and Relative Position on Electromagnetic Performance of Partitioned Stator Switched Flux Permanent Magnet Machines 被引量:1
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作者 J.T.Shi Z.Q.Zhu 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第3期259-268,共10页
Based on the 6-pole outer stator(armature winding-stator),the influence of inner(permanent magnet-stator)/outer stator pole ratio n(n=NIS/NOS),stator relative positions and rotor pole number combinations on electromag... Based on the 6-pole outer stator(armature winding-stator),the influence of inner(permanent magnet-stator)/outer stator pole ratio n(n=NIS/NOS),stator relative positions and rotor pole number combinations on electromagnetic performance of partitioned stator switched flux permanent magnet(PM)machines(PS-SFPMMs)is investigated in this paper.Since the armature windings and PMs are located in two separated stators and PMs are stationary,PS-SFPMMs have high fault tolerance capabilities.To maximize the torque performance,the PM of inner stator pole should be aligned with outer stator pole when n is odd while the iron rib of inner stator pole should be aligned with outer stator pole when n is even.No matter what n is selected,the rotor pole number NR can be any integers except the phase number and its multiples.The analysis results indicate that the optimal NR is closed to(NIS+NOS)/2 and it is odd when n is odd while it is even when n is even.Meanwhile,symmetrical phase back-EMF waveform will be obtained when the ratio of Min(NOS,NIS)to the greatest common divisor of Min(NOS,NIS)and NR is even.Based on the optimal rotor pole numbers for 6-pole outer stator with different n and corresponding optimal relative position together with same rated copper loss,the average torque is improved by 18.4%,25.1%and 25.7%respectively in PS-SFPMMs with n equal to 2,3 and 4 when compared with PS-SFPMM with n equal to 1.The analyses are validated by experiment results of the prototype machine. 展开更多
关键词 Inner/outer stator partitioned stator permanent magnet pole ratio relative position switched flux.
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