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Long L.-J.,Wuhan University | Xu J.-M.,Wuhan University | Gong Y.-S.,Wuhan University | Wu M.-Y.,Wuhan University | Cui X.-Y.,Wuhan FiberHome Fuhua Electrical Co.
Wuji Cailiao Xuebao/Journal of Inorganic Materials | Year: 2015

Lead lanthanum zirconate titanate(PLZT) powders synthesized by partial co-precipitation method were used to fabricate PLZT ceramics by conventional muffle furnace or by microwave muffle furnace. The crystal structure, microstructure, electrical properties of PLZT ceramics prepared by these two methods were investigated. The results show that the PLZT ceramics sintered by these two methods are pure perovskite structure. Microwave sintered PLZT ceramics possess smaller grain, more uniform size and less holes than do the conven tional prepared. The microwave sintering temperature is much lower than that by the conventional method, and the duration time is also much less, while the electrical properties of the ceramics sintered by these two methods are similar. The best properties of PLZT ceramics can be gained by microwave sintering at 1000℃ with dielectric constant and piezoelectric constant of 2512 and 405 pC/N. The remnant polarization is 16.5 kV/cm, and the coercive field is 8.2 μC/cm2. The dielectric constant and piezoelectric constant of PLZT ceramics sintered by conventional method at 1250℃ reach the maximum values of 2822 and 508 pC/N. The remnant polarization is 21.6 kV/cm and the coercive field is 9.6 μC/cm2. ©, 2015, Science Press. All right reserved. Source

Cui Y.,North China Electrical Power University | Cui Y.,Lankao Power Company | Hong H.,Henan Electric Power Company | Zeng Z.,Jiangxi Jian Power Company | Zhu B.,Wuhan FiberHome Fuhua Electrical Co.
Gaoya Dianqi/High Voltage Apparatus | Year: 2012

This paper puts forward a thought, which transform the cooling system of existing trditional transformer. The foucs of the transformation is optimization and design of the radiator, and the calculation of the method is also confirmed viably. With new cooling system replaced the previous one and equiped the high-quality blowing device and control box, eventually, it reach the requirements of energy saving, noise reduction and safe operation of transformer. Finally, the transformation of the cooling system of main transformer in a substation of a power supply corporation proved that the method have very strong practicability. Source

Cui Y.,North China Electrical Power University | Cui Y.,Henan Lankao County Power Supply Company | Wang C.,Jiangxi Jian Power Supply Company | Yang J.-H.,Jiangxi Jian Power Supply Company | And 2 more authors.
Gaoya Dianqi/High Voltage Apparatus | Year: 2011

To enhance the efficiency of inspection and repair, fault types of control circuit of high voltage circuit breaker are analyzed, and the characteristics of hidden faults in the control circuit are described. A case study of the hidden faults inspection demonstrates the effectiveness and rapidness of the inspection and repair method. In addition, the main causes of hidden faults are analyzed, and corresponding countermeasures are offered. Source

Wang X.,Wuhan Research Institute of Posts and Telecommunications | Xu L.,Wuhan FiberHome Fuhua Electrical Co. | Li X.,Wuhan FiberHome Fuhua Electrical Co. | Cui X.,Wuhan FiberHome Fuhua Electrical Co.
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2015

In order to improve real-time and reliability performance of transmission of Generic Object Oriented Substation Event (GOOSE) packets, a fast and effective GOOSE decoding method based on Field Programmable Gate Array (FPGA) is given. Taking advantage of FPGA's parallel execution mechanism, the finite state machine of GOOSE message decoding and the judging process of subscription checking are designed and realized. Through behavior simulation and waveform capture, it verifies functions of GOOSE filtration and fast decoding, and GOOSE link self-check in high network flows. Compared with the traditional CPU's sequential processing mode, the FPGA-based design of real-time messages decoding in substation has better performance of real-time and reliability, which provides a new idea for design and development of process layer devices. © 2015, Power System Protection and Control Press. All right reserved. Source

Peng N.,Wuhan National Laboratory for Optoelectronics | Peng N.,Wuhan FiberHome Fuhua Electrical Co. | Huang Y.,Comcore Technologies Inc. | Wang S.,Wuhan National Laboratory for Optoelectronics | And 4 more authors.
IEEE Photonics Technology Letters | Year: 2013

A fiber optic current sensor based on a polarization-rotated reflected interferometer has been constructed. A special spun highly birefringent fiber is designed and achieved for the sensor by heating and spinning commercial linearly birefringent fiber. In contrast with conventional fibers, the fiber integrates a function of a quarter wave plate. Particularly, fabricating and working principle of the current sensor head using the fiber are expounded. The sensor achieves an accuracy with 0.5% and good linearity shown in temperature dependence (a temperature drift of 0.008%°C over a temperature range 40°C -70°C. Further, under simple temperature compensation, the sensor accuracy is within ±0.1% over in a wide range of current and temperature ranges. © 1989-2012 IEEE. Source

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