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Chen J.,Wuhan University | Guo S.,Wuhan University | Liu P.,Wuhan University | Li Y.,Wuhan University | And 2 more authors.
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2012

This paper develops a joint operation and dynamic control model of flood limited water levels for optimization of cascade reservoirs' economic benefits without lowering design flood protection standards, based on large-scale system decomposition and coordination theory. This model was tested in a case study of the Qingjiang cascade reservoirs by comparing the dynamic joint optimization with the design operation, using flood data series of three-hours for typical wet, normal and dry years. Results show that the proposed model generated an extra power output of 179 million kW·h or a 4.51% increase and a 2.73% increase in flood water use, relative to the design operation scheme. Thus, joint operation of flood limited water levels greatly enhances comprehensive benefits of cascade reservoirs. © copyright.


Hu J.,Hubei Qingjiang Hydropower development Co.
APAP 2011 - Proceedings: 2011 International Conference on Advanced Power System Automation and Protection | Year: 2011

The consolidated differential protection could not be installed in generator in many old hydraulic power plants they are in running. Affected by various factors, the mal-operation of turn-to-turn protection based on other principles occurs easily. For a long time in operating the power plant, to prevent the mal-operation of turn-to-turn protection is a key point, so the turn-to-turn protection in actual operation is often ineffective. For large multi-polar hydraulic generator, if the turn-to-turn protection failed to operate, it will produce incalculable damage. It is so quite important to simulate before installing the main protection in new generating-sets. For the generators have not been simulated, this paper proposes a new simple setting method, which uses stator winding spreading figure to analyze the potential circle number of upper and lower stator bars in the same lot of same phase. It is of more practical value than both setting according to "Guideline" and setting blindly. From the analysis about the stator structure, turn-to-turn protection configuration, setting and operation history of 11 representative large hydraulic generators along the Qingjing River Valley, it can be drawn that turn-to-turn protection of old generating-sets is almost out of work which is installed before 2001 and the sensitivity of 17.5% new generating-sets put into operation by 2007 can't be guaranteed. It also indicates that excitation system impact considerably on main protection of generator. This paper discusses the turn-to-turn protection of large hydraulic generator. © 2011 IEEE.


Su Q.,China Three Gorges University | Hu Z.,Environmental Protection Institute | Li H.,Hubei Qingjiang Hydropower development Co. | Peng W.,China Three Gorges University
Journal of Computational Information Systems | Year: 2015

A pollution estimating approach by discrete particle swarm optimization with hierarchical structure is proposed in this paper. Discrete particle swarm optimization with hierarchical structure aims to improve the performance of PSO by offering accurate best solution and faster convergence speed. The discrete particle swarm optimization with hierarchical structure is used to optimize the SVR. It can be seen that the pollution estimating results of SVR optimized by discrete particle swarm optimization with hierarchical structure are better than those of SVR optimized by particle swarm optimization, and SVR. Therefore, discrete particle swarm optimization with hierarchical structure has very high application value in pollution estimating. Copyright © 2015 Binary Information Press.


Liu P.,Wuhan University | Zhang W.,Hubei Qingjiang Hydropower development Co. | Li T.,Wuhan University
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2013

This paper focuses on deriving reservoir operating rule curves by adding a risk objective function to maximize the annual power output and the assurance rate of hydropower station. The risk is defined as the probability of generated power less than that specified by the conventional curves. Two models are therefore developed, one for maximizing the annual output and its assurance rate, and the other for minimizing this risk. Application to a case study of the Geheyan reservoir shows that the proposed method can improve the hydropower output greatly and reduce the risk simultaneously.


Su Q.,China Three Gorges University | Hu Z.,Environmental Protection Institute | Li H.,Hubei Qingjiang Hydropower development Co. | Peng W.,China Three Gorges University
Journal of Computational Information Systems | Year: 2015

In the study, a hybrid model of non-uniform particle swarm optimization algorithm and support vector regression algorithm is proposed to evaluate the water pollution. Particle swarm optimization (PSO) is a swarm-based stochastic algorithm. PSO algorithm simulates the social behavior of bird ocking, which can incorporate both a global inuences for the swarm of individuals and local inuences from neighbors. However, particle swarm optimization algorithm can be trapped into local optimum easily, non-uniform PSO particle swarm optimization algorithm is employed to improve the optimal ability of normal particle swarm optimization algorithm. Water pollution evaluation can be used as the application of non-uniform PSO-SVR and used to analyze the feasibility of non-uniform PSO-SVR for pollution evaluation. The testing results show that the overall error of the non-uniform PSO-SVR model are less than that of the PSO-SVR model and the GA-SVR model. It is observed that the proposed non-uniform PSO-SVR model has higher evaluation ability for water pollution than the PSO-SVR model or the GA-SVR model. ©, 2015, Journal of Computational Information Systems. All right reserved.

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