Chen M.,Chongqing University |
Yu L.,Chongqing University |
Wade N.S.,Durham University |
Liu X.,Chongqing Nanping Power SupplyBureau |
And 2 more authors.
IEEE Transactions on Power Electronics | Year: 2011
Different faulty states of a doubly fed induction generator (DFIG) connected to a microgrid are investigated in this paper. First, the simulation model consisting of two DFIGs connected to IEEE 34-bus test feeder for two vector control based was set up to investigate the transient performance of the microgrid. Then, different types of faults of the DFIGs, including partial loss of excitation (PLOE), complete loss of excitation (CLOE), and interturn short circuit (ISC) were analyzed through the simulation model using vector control strategy. The experimental results indicate that the active power will increase during the PLOE, and the average increase of the amplitude is about 26%, which will decrease the electromagnetic torque by 8% and increase the voltage at the neighbor node, the stability of the microgrid will be broken eventually. For the CLOE, the active power decreases about 80%, and node voltage decreases by 9.4% due to the inverse absorption of the reactive power. When the ISC occurs, the average node voltage and the active power decrease together. Finally, the suggestion for the detection of the DFIG faults is presented, which could be helpful to protect the DFIG from fault accident. © 2011 IEEE.
Bing X.,Chongqing Shiqu Power Supply Bureau |
Fuping W.,Chongqing Shiqu Power Supply Bureau |
Sheng W.,Chongqing Shiqu Power Supply Bureau |
Shaodong W.,Chongqing Power Grid Maintenance Company
China International Conference on Electricity Distribution, CICED | Year: 2014
Power supply reliability means the power system's ability of sustainable power supply, which is a main index in evaluating the quality of power supply system. In order to improve the reliability of urban distribution network and quality of service, Chongqing Power Corporation made urban core area of 31.5 square kilometers as demonstration area on power supply high-reliability, with the acceptance of the State Grid Corporation in 2013. The average interruption duration is reduced lower than five minutes, which reached the international advanced level. The construction of this demonstration area mainly include reliability evaluation on distribution grid, reliability planning on grid structure, cable non-blackout work, reconstruction on distribution grid, risk analysis on distribution grid operation, production and command platform construction, condition-based maintenance technology, construction of standard operation and management system on regional distribution with high reliability, etc. Remote loop closing operation is achieved by data interaction between distribution automation system and the loop closing operation device. Through the information exchange bus, distribution automation system, production management system (PMS), 95598 system, geographic information system (GIS), reliability risk assessment system, online-monitoring system and condition-based maintenance system are integrated together. By using PMS mobile operating platform to process work orders, the efficiency of rushing repair is improved significantly. With the widely application of infrared radiation thermometer and Oscillation Wave Test System (OWTS), not only Condition-based maintenance of distribution network equipment is carried out, but the process of distribution grid maintenance and recovery can be monitored. After the construction of high reliability demonstration area, the average shut down time decreased from 33 min. to 4.557 min., the reliability index (RS-3) increased from 99.96% to 99.9915%, and service quality on power supply and customers' satisfaction also increased significantly, and consequently good society and commercial benefit were made. © 2014 IEEE.
Zhao X.-Y.,Chongqing Power Grid Maintenance Company |
Cheng J.-B.,Chongqing Power Grid Maintenance Company |
Wang X.-Q.,Chongqing Power Grid Maintenance Company |
Wang L.,Chongqing Power Grid Maintenance Company
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2011
This paper researches in depth on how to estimate the immediate support ability of power maintenance company when power grid is in a state of emergency. This has been a perplexed issue for a long term. From the practical perspective, taking the staff, supplies, facilities required and some other factors into consideration, a three-level index system is introduced and the power grid Urgent Guarantee Index (UGI) is established. In the UGI system, Multi-objectives Particle Swarm Optimization (IMOPSO) algorithm is employed to get the optimal solution for the weighting distribution, using the practical maneuver score as objective function. The final weight value of all factors is acquired by the Self-adaptive Weight method. The index (UGI) is the sum of respective scores multiplied by corresponding weight value. Through comparing the index (UGI) with the data obtained in practical maneuver, the UGI system is proven to be practicable and effective.
Yang F.,Chongqing University |
Cheng P.,Chongqing University |
Yang Y.,Chongqing University |
Chen J.,Chongqing Power Grid Maintenance Company |
Chen T.,Chongqing Electric Power Research Institute
Asia-Pacific Power and Energy Engineering Conference, APPEEC | Year: 2012
To increase the current carrying capacity of the power cable, more and more power tunnel are installed with ventilation. Hence in the paper the heat dissipation of power cable is investigated. Firstly the model to calculate the thermal field of power cable with natural ventilation is presented based on the fluid mechanics and heat transfer, and the governing equations and boundary conditions are inferred. Then the thermal field for six-loop cables in power tunnel was calculated, which verified the accuracy of the model. In addition, the factors influencing the thermal field with ventilation is investigated, including the size of the power tunnel, the distance between the cable. Finally the current carrying capacity of the power cable is calculated and the economic benefit of the operation mode of power cable is analyzed. © 2012 IEEE.