Advanced Materials Research Vols. 512-515

Abstract: Coordination strategies between short-term (e.g., weekly and daily scheduling ) and real-time scheduling in wind power integrated system are disscussed. To cope with the uncertainty of wind power and load demands, weekly and daily rolling schedulings are applied. According to the latest updated prediction results of wind power and load demands, weekly rolling scheduling is applied to revise unit commitment and fuel allocation in remaining hours in a week. Daily rolling scheduling is applied to revise generation scheduling in remaining time in a day. A modified IEEE 118-bus system is applied to test the proposed approach.

Abstract: In the pursuit of renewable energy, high altitude wind is gaining increased attention for its better strength, steadiness, and coverage over the ground wind. In this paper, we will describe our development on EHAWK (Electric from High Altitude Wind with Kite), a robotic kite system to generate electricity from wind. So far we have designed and tested several generations of EHAWK systems and gained experiences on harnessing the high altitude wind on both experimental and theoretical fronts.

Abstract: To improve the utilization of wind power generation system(WPGS), this paper presents a novel matching method on fixed pitch wind turbine(WT) design considered the total efficiency of WPGS. Based on detailed efficiency discussion of permanent magnet synchronous generator (PMSG), at present, the basic data included efficiency of wind power generator (WPG) has mature acquire measures with high accuracy. On the contrary, the efficiency of WT is relatively difficult to obtain accurately, and because of the poor matching research between WPG and WT, there may be a potential problem that the total efficiency of WPGS is not the best. Based on the basic data of the WPG, through the calculation of expected total efficiency and WPG efficiency, compared with the existing curve of the WT features, this method can attain an ideal WT efficiency( ) curve which fit expected total efficiency of WPGS and has a good matching behave with the WPG. It provides a new way for the type selection, design, and manufacture of WT, which is easy calculated, low cost of design, and has good expected matching with system.

Abstract: Abnormal vibration appeared when experimental tests was carried out on gearboxes of a 1.5MW wind turbine. In this paper, Time-domain and frequency- domain analysis of test data was implemented based on the method of wavelet denoising, the fault location was determined, and the vibration fault indicators and frequency components were obtained. The finite element model of the gearboxes were established, and the natural frequencies and mode shapes were achieved by calculating. The results showed that the fault occurred in the high speed shaft parts, fault vibration frequency was caused by high-speed shaft eccentric resonance frequency and the frequency generated by the natural frequency and the edge frequency that caused by turning. The research layed the foundation for the study of noise reduction and optimization of the wind turbine gearboxes.

Abstract: The hybrid wind/PV/pumped-storage power system was the hybrid system which combined hybrid wind/PV system and pumped-storage power station. System optimization was very important in the system design process. Particle swarm optimization algorithm was a stochastic global optimization algorithm with good convergence and high accuracy, so it was used to optimize the hybrid system in this paper. First, the system reliability model was established. Second, the particle swarm optimization algorithm was used to optimize the system model in Nanjing. Finally, The results were analyzed and discussed. The optimization results showed that the optimal design method of wind/PV/pumped-storage system based on particle swarm optimization could take into account both the local optimization and the global optimization, which has good convergence high precision. The optimal system was that LPSP (loss of power supply probability) was zero.

Abstract: Due to the large WTGS experiment difficulties, running environment complex and changeable, running condition is not prediction and not reproducibility and other characteristics, so the wind power control system development and testing of extremely limited. This paper introduce a large-scale WTGS main control test system, of which the WTGS model is built to simulate operation conditions of wind farm. By this way, reproducing the operation conditions is available, testing and debugging WTGS can go well without the influence of the randomness and intermittence of wind.

Abstract: Hopf bifurcation frequently results in periodical oscillation instability in the nonlinear system. For Hopf bifurcation at equilibrium point in the wind power system, Hopf bifurcation point of the wind power system with static var compensator is calculated based on the continuation method. The analysis shows that the increase of reactive power will lead to Hopf bifurcation, static var compensation can delay Hopf bifurcation and improve voltage stability region via reactive power compensation, in order to eliminate Hopf bifurcation, a unified and simple linear feedback control method is adopted. The results indicate that the method put forward in the research is effective to eliminate Hopf bifurcation in the wind power system

Abstract: Wind energy as a clean and can continue to use the new energy is widely used in central and western regions of China. Wind power has a strong volatility, when the large capacity of wind power connected to the grid, this volatility has many negative effects on the safe and stable operation of the grid. Therefore, the wind power prediction system has become the most wind farm necessary security early warning systems. There is an important part of the system that is called the wind power meteorological data acquisition system and its function is to provide for the system the original meteorological data, meteorological data will become an important basis for the prediction function. This article will describe the developed by the Changchun Meteorological Instrument Research Institute, "AMS-II-E wind electric power meteorological data acquisition system", the composition and the core processing algorithms. The system has been equipped with 15 wind power plants in four provinces in China (Inner Mongolia, Jilin, Liaoning, Jiangsu).

Abstract: According to iterative phase pitch torque of the rotation wind turbine, this paper proposes one-way stop device to achieve the feather state and the purpose of the safe shutdown by the torque of blade itself ,not only to solve the question that energy storage device ,for example battery, super capacitor or hydraulic accumulator,is broken easily, but also reduces the cost of a wind turbine.

Abstract: As a clean and renewable energy, the wind power has attracted the attention of all nations in the world. Evaporative cooling technology has successfully been used in the research and development of wind power generator, but some key technique has to be studied in advance to insure the reliability of the very technology. The application of evaporative cooling technology in the cooling of large wind power generator is a new attempt in the discovery of wind power energy. Thorough study is carried out on the key technique of the application of close-loop self-circulation (CLSC) evaporative cooling technology on the running of wind power generator. The flow resistance of the coolant in the air cooling condenser is discussed in this paper, and a new approach is founded for the improvement of the reliability.