科创中国

This paper presents an equivalent magnetic circuit model to predict the leakage effect, especially the end leakage effect, of surface-mounted permanent magnet synchronous machine (SPMSM) in rim-driven marine current power (RMCP) system. The end leakage effect is usually neglected in most conventional permanent magnet (PM) machines. However, it is significant in the electrical generator of RPCM due to the short axial length. The idealized path and analytical expressions of end leakage permeance are given in this paper. Finite Element Method (FEM) 3D/2D and experimental values are presented to validate the proposed analytical model. With no need for the time-consuming FEM-3D calculation, a correction factor base on the analytical mode is proposed to adjust the results (e.g. back-EMF, torque) of conventional design when end leakage is ignored in the calculation. The calculation results and experimental values show that the proposed analytical model is accurate to analyze the leakage effects of SPMSM in RMCP system.

Song Xu;海峰 王;国彪 顾

2014

Generator-motor frequently starts up and shuts down, changes running conditions during daily operation, which generating frequent changing temperature and thermal stress. This working characteristic goes against safety reliability of generator-motor. As the temperature and thermal stress are directly related to cooling method of generator-motor, this paper used theoretical analysis method and finite element simulation method to analyze the temperature and thermal stress of stator bar in air-cooled and evaporative-cooled generator-motor when the electrical machine operate from stop state to rated status. To ensure the calculation precision, the real operation data of a 300MW generator-motor in China and the actual measuring material parameters of VPI insulation were chosen as input for the finite element simulation. The results show that if generator-motor is cooled by evaporative cooling technology, the temperature and thermal stress fluctuation of stator bar caused by load changing can be effectively reduced and the safe reliability of generator-motor can be effectively improved.

Jinxiu Chen;Lin Ruan;国彪 顾

Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering

2017-2-5

According to the development demand of large turbo generator,this paper introduces the theory and structure of evaporative cooling system of turbo generator's stator and rotor. After in detail analyzing the technical feasibility of applying evaporative cooling technique to large turbo generator, a conclusion that scheme based on stator soakage evaporative cooling and rotor open channel evaporative cooling is feasible for large turbo generator is obtained. Meanwhile, this paper introduces the simulating experiment of open channel evaporative cooling of turbo generator's rotor windings. The aim of experiment is to get the temperature distribution of rotor winding in the direction of radius and roughly estimates the power of cooling, aiming at offering technical references for the application of evaporative cooling technique in large turbo generator and for exploring new cooling structure.

Tao Yao;Zhe Hou;国彪 顾

Diangong Jishu Xuebao/Transactions of China Electrotechnical Society

2008-2

Based on the structural characteristic of flux-switching machines with segmental rotor, the drawing method of distribution diagram and the coil-EMF vector graph, which illustrate the space and electrical angle difference of the coils respectively, was developed and verified by finite element analysis method at the beginning of the paper. Further, a phase winding division method, which is suitable for any phase segmented-rotor flux-switching machines, was proposed and also confirmed by finite element analysis method. In further, based on the analysis of the single coil harmonic characteristics and the coil-EMF vector graph developed in this paper, the principle of combination of stator teeth and rotor pole numbers to achieve back-EMF without even harmonic was given and also verified by finite element analysis method. At last, guided by the phase winding division method and the principle of combination of stator teeth and rotor pole numbers proposed in this paper, a 3-phase segmented-rotor flux-switching machine prototype was designed and the experiment results verified the above research conclusion well.

Guangkun Lian;彪 陈;Fei Ban;国彪 顾

Diangong Jishu Xuebao/Transactions of China Electrotechnical Society

2020-1-25

when we design immersing evaporative cooling turbo generator, How to control the temperature rise of stator bars in an appropriate situation is one of the most important parts in the unit designing. In this paper, the heat flowing paths of stator components are analyzed in the immerging stator structure. Based on the heat transfer theories, Numerical simulation model is built for the stator temperature distribution. The FEA (Finite Element Analysis) is used to the simulation analysis, and get the temperature rises of parts and the heat fluxes of heat flowing paths. To verify the analysis and calculation results, we built the experiment model of stator. Compare the calculation results with experiment results, and we get many valuable analytical methods and designing criterions for evaporative cooling turbo generator.

Bin Xiong;国彪 顾;Lin Ruan;Zhen Guo Li;De Ping Fu;Jin Shui Gao

2013

Traditional electron cyclotron resonance (ECR) ion source coil with higher power density have some disadvantages, such as high pressure in the water-cooling system, restricted cooling ability, complex maintenance and operation system. A new ECR ion source coil was designed by using self-circulation evaporative cooling technology. The new design is based on the principle of self-circulation evaporative cooling, besides, the layout structure of ECR ion source coil and high operation reliability are both considered. The coil is composed by disk coil arrays. Vertical cooling channels are set among unit coils, where evaporative cooling coolant flows automatically driven by the heat of coils. According to the parameter index of LECR - DRAGON ion source magnet coil, the test model of evaporative cooling magnet coil was built. The experimental results show that the window current density of the new designed coil can be 12A/mm², which can maintain a long-term stable and reliable running.The evaporative cooling magnet coil can meet the requirements of practical engineering.

Bin Xiong;Lin Ruan;国彪 顾;Shu Qin Guo;Rui Cao;Zhen Guo Li;Wang Lu;Xue Zhen Zhang;红卫 赵;良亭 孙

Dianji yu Kongzhi Xuebao/Electric Machines and Control

2016-1-1

In daily operation of pumped storage station, generator-motor is featured with frequent start up and shut down, sharp operating load change. With the development of higher capacity and water head in recent years, the effects of thermal stress generated in operation load change on pumped storage unit's safety and reliability have become more and more serious. Thermal stress not only has relation with the changing rate of thermal load and structure feature of generator-motor, but also is directly affected by cooling method. Firstly, the advantages and disadvantages of different cooling methods when applying in generator-motor are qualitatively analyzed in this paper. Then the design principle of thermal cycle test is proposed in order to compare the effects of different cooling modes on thermal cycle aging of insulation system. Finally, the maximum partial discharge is used as the representative parameter of the insulation characteristics. Through thermal cycle test, the influence of cooling mode on the insulating characteristics of pumped storage units was analyzed. The experimental results indicate that the anti-aging capability of evaporative cooling stator bar is much better than that of air cooling stator bar.

Lin Ruan;Jinxiu Chen;国彪 顾

Diangong Jishu Xuebao/Transactions of China Electrotechnical Society

2017-7-25

In recent years safety accidents of large-scale wind turbine occur frequently. Because of the structure specialization of wind turbine, in case of an accident, the entire unit is often completely destroyed and economic losses will be very high. This paper presents some phased research results on serious wind turbine accidents and put forward appropriate countermeasures for different types of accidents.

Zhe Hou;国彪 顾

2012

We would encounter the output torque balance problem of several motors during many industry productive processes such as steel rolling, papermaking, printing, electric vehicle, ship propelling and so on in modern times. However the normal speed control method can't meet with the requirements of the multi-motors output torque balance for that the load of different motor may not be equal and the different motor parameters owing to the motor productive process. So that, how to make the output torque of the different motors to be in equilibrium becomes an important problem. In this paper the author designs the torque balance control system of two motors by using digital signal processing (DSP) and modern control theory. The simulation experiment verified its performance through setting up its digital simulation model. The concrete device is in the development.

Zhen Yuan;海峰 王;Jie Yang;国彪 顾

2007

Switched reluctance machine (SRM) and flux-switching machine (FSM) with segmental rotors are different in winding patterns and control strategies. The electromagnetic characteristics of the two machines, including magnetic field, static torque, torque ripple, iron loss and efficiency, are compared by means of analytical calculation and finite element method in this paper. The analytical results of this paper provide a theoretical guidance for choosing between the two types of machines in specific applications.

Guangkun Lian;国彪 顾;Yunkai Cheng;Jie Tao;Sixiang Wang;Xiaoyuan Chen

2016-1-18