Time filter

Source Type

Pingdingshan, China

Zou G.-P.,Pinggao Electrical Co.
Gaoya Dianqi/High Voltage Apparatus

The working principle of hydraulic mechanism for high voltage circuit breaker is introduced, and the source of air contamination in hydraulic system is analyzed. The harms of the air contamination to the circuit breaker are emphatically discussed, including oil leakage, unstable action time, and cavitation. Moreover, the methods for preventing air contamination are proposed, such as avoiding the air retention through improvement of structure design and whole layout, and exhausting the air by vacuum pump or exhaust valve, for the purpose of controlling air contamination effectively. Source

Zhong J.-Y.,Pinggao Electrical Co. | Di Q.,China Electric Power Research Institute
Gaoya Dianqi/High Voltage Apparatus

Inner shielding layer of 550 kV SF 6 gas-insulated GIS bushing is introduced in this paper. Against to the problem of assembly difficulty, high partial discharge and high cost, through 550 kV SF 6 gas-insulated GIS bushing electric field model and optimum design, single shield structure is selected. So the problems of assembly difficulty, high partial discharge and high cost are solved effectively. Each performance index of bushing satisfies the technical specifications request through type test, and has big tolerance. So the bushing has good technical economy index. Source

Di Q.,China Electric Power Research Institute | Zhong J.-Y.,Pinggao Electrical Co.
Gaoya Dianqi/High Voltage Apparatus

Development of the three phases in one tank type SF 6 gas-insulated 110 kV voltage transformer is introduced. The single-phase double-column overlap core was designed, and its 7-step trapezoid section made the utilization factor close to 1. The high-voltage winding adopted the tower structure with a two-layer mode in order to fully utilize interlayer isolation. The three-dimensional electric field distribution was calculated by finite element method for the design of main insulation structure. After optimum design, reasonable selection of materials and fine fabrication, this type of transformers passed all tests and met the relational standard. Source

Qian C.,Anhui University | Qian C.,Hefei Sungrow Power Supply | Zhu M.,Anhui University | Xia Z.,Anhui University | And 2 more authors.
Dianli Xitong Zidonghua/Automation of Electric Power Systems

A method of responsibility proration among multiple three-phase unbalanced sources based on the reference impedance method is proposed. A mathematical model of responsibility proration among multiple three-phase unbalanced sources is developed, four quantitative indicesare defined, and the detailed implementation steps are given. The validity and rationality of the method are proved by a simulation system model with three users and the measured data of a 10 kV power system in a steel plant. Finally, the sensitivity analysis between reference impedance and quantitative indices shows that the error of the method is small owing to the improved accuracy of the responsibility proration among multiple three-phase unbalanced sources. © 2014 State Grid Electric Power Research Institute Press. Source

Lei J.,Wuhan University | Zhong J.-Y.,Pinggao Electrical Co. | Wu S.-J.,Wuhan University | Wang Z.,Pinggao Electrical Co. | And 2 more authors.
Journal of Electrical Engineering and Technology

Busbar has been used as electric conductor within extra high voltage (EHV) gas insulated switchgear (GIS), which makes EHV GIS higher security, smaller size and lower cost. However, the main fault of GIS is overheating of busbar connection parts, circuit breaker and isolating switch contact parts, which has been already restricting development of GIS to a large extent. In this study, a coupled magneto-flow-thermal analysis is used to investigate the thermal properties of GIS busbar in steady-state. A three-dimensional (3-D) finite element model (FEM) is built to calculate multiphysics fields including electromagnetic field, flow field and thermal field in steady-state. The influences of current on the magnetic flux density, flow velocity and heat distribution has been investigated. Temperature differences of inner wall and outer wall are investigated for busbar tank and conducting rod. Considering the end effect in the busbar, temperature rise difference is compared between end sections and the middle section. In order to obtain better heat dissipation effect, diameters of conductor and tank are optimized based on temperature rise simulation results. Temperature rise tests have been done to validate the 3-D simulation model, which is observed a good correlation with the simulation results. This study provides technical support for optimized structure of the EHV GIS busbar. © The Korean Institute of Electrical Engineers. Source

Discover hidden collaborations