Study on integrated development and hybrid operation mode of nuclear power plant and pumped-storage power station

The nuclear power plant is suitable for base-load operation, while the pumped-storage unit mainly gives play to capacity benefit in the electric power system;hence, the integrated development and hybrid operation mode of the two can better meet the needs of the electric power system. This article first presents an analysis of the necessity and superiority of such mode, then explains its meaning and analyzes the working routes. Finally, it proposes the business modes as follows: low price pumping water electricity plus nuclear power in the near term;nuclear power shifted to pumped storage power participating in market competition in the middle term;and, in the long term, nuclear power shifted to pumped storage power as primary and serving as an electric power system when needed.

Prospect of new pumped-storage power station

In this paper, a new type of pumped-storage power station with faster response speed, wider regulation range, and better stability is proposed. The operational flexible of the traditional pumped-storage power station can be improved with variable-speed pumped-storage tech no logy. Combined with chemical en ergy storage, the failure to achieve sec on d-order response speed and the insufficient safety and reliability of pumped-storage power units could be solved. With the better solar en ergy and site resources, the in teg rated performance can be improved by an optical storage system in stalled in future pumped-storage stations. Through the characteristics analysis of the new type of pumped-storage power station, three types of optimal station locations are proposed, namely, the load concentration area, new energy concentration area, and ultrahigh- voltage direct current receiver area. Taking the new pumped-storage power station as an example, the advantages of multi-energy cooperation and joint operation are analyzed. It can be predicted that the frequency and load regulation of the power grid will be more flexible, and the service capacity to the main power grid will be much stronger in the future.

An optimal strategy for coordinating and dispatching “source-load” in power system based on multiple time scales

Due to the phenomenon of abandoning wind power and photo voltage(PV)power in the“Three Northern Areas”in China,this paper presents an optimal strategy for coordinating and dispatching“source-load”in power system based on multiple time scales.On the basis of the analysis of the uncertainty of wind power and PV power as well as the characteristics of load side resource dispatching,the optimal model of coordinating and dispatching“source-load”in power system based on multiple time scales is established.It can simultaneously and effectively dispatch conventional generators,wind plant,PV power station,pumped-storage power station and load side resources by optimally using three time scales:day-ahead,intra-day and real-time.According to the latest predicted information of wind power,PV power and load,the original generation schedule can be rolled and amended by using the corresponding time scale.The effectiveness of the model can be verified by a real system.The simulation results show that the proposed model can make full use of“source-load”resources to improve the ability to consume wind power and PV power of the grid-connected system.

天堂抽水蓄能电站发电电动机中性点接地装置研制

湖北天堂抽水蓄能电站发电机中性点采用带二次负载电阻配电变压器的接地方式。当机组发生单相接地短路故障时,接地装置通过电阻损耗功率对电容性无功功率的补偿,将暂态过电压限制在机组绝缘允许范围内,同时在接地保护配合下,经短延时切除机组,可避免机组在故障状态下继续运行而导致事故扩大。该装置于2001年投入电网运行,迄今工作稳定、正常,收到了预期效果。

天堂抽水蓄能电站的设计特点

天堂抽水蓄能电站为湖北省乃至华中地区第一座抽水蓄能电站,电站上下库均利用已建水库,工程总体布置能够因地制宜地开展,并优化了原有水库参数和运行方式,从而增加了调峰容量和效益;在深入研究水道系统调节保证的基础上取消了调压井;调整了尾水检修门位置,方便了拦污栅的检修;充分利用围岩承载,减小了衬砌厚度;从而增加了调峰容量和效益,最大限度地节省了投资、缩短了工期。

Study on S-shaped characteristic of Francis reversible unit by on-site test and CFD simulation

The operation parameters （vibration, shaft displacement and pressure fluctuation） of No. 1 Francis reversible unit of Baoquan pumped-storage power station were measured on site in the no-load mode at net heads of 518.04, 522.01 and 530.38 m, re- spectively. The rotational speed fluctuations in the no-load mode at three net heads were beyond synchronization requirement with obvious S-shaped characteristic, and misaligned guide vanes （MGV） had to be put into use for synchronization. Further analysis demonstrated that the rotating frequency signal was generally dominant in vibration and shaft displacement mixing signal in the no-load mode, while the frequency domain was wide without an obvious main frequency in pressure fluctuation mixing signal. Besides, the SSTκ-ω turbulence model was adopted to simulate the four quadrant characteristic curves of Baoquan model pump-turbine at three gate openings, and the relative error between simulation results and model test data was within ±6%, indicating that the simulation method in this paper is feasible and S-shaped characteristic of the pump-turbine can be simulated with CFD method.