scholarly journals Analysis of flow characteristics in pumped storage unit during start-up in turbine mode

2021 ◽  
Vol 1985 (1) ◽  
pp. 012051
Author(s):  
Tao Liu ◽  
Chao Wang ◽  
Zhiming Chen ◽  
Funan Chen ◽  
Huili Bi ◽  
...  
Keyword(s):  
Flow Characteristics ◽  
Storage Unit ◽  
Start Up ◽  
Pumped Storage ◽  
Turbine Mode

Research and Develop on Static Frequency Converter of Pumped Storage Power Plant

2012 ◽  
Vol 608-609 ◽  
pp. 1120-1126 ◽  
Author(s):  
De Shun Wang ◽  
Bo Yang ◽  
Lian Tao Ji
Keyword(s):  
Power Plant ◽  
Control Strategy ◽  
Large Scale ◽  
Frequency Converter ◽  
Position Estimation ◽  
Position Sensor ◽  
Storage Unit ◽  
Rotor Position ◽  
Start Up ◽  
Pumped Storage

A static frequency converter start-up control strategy for pumped-storage power unit is presented. And rotor position detecting without position sensor is realized according to voltage and magnetism equations of ideal synchronous motor mathematics model. The mechanism and implementation method of initial rotor position determination and rotor position estimation under low frequency without position sensor are expounded and validated by simulations. Based on the mentioned control strategy, first set of a static frequency converter start-up device in China for large-scale pumped-storage unit is developed, which is applied to start-up control test in the 90 MW generator/motor of Panjiakou Pumped-storage Power Plant. Test results show that rotor position detecting, pulse commutation, natural commutation, and unit synchronous procedure control of static start-up are all proved. The outcomes have been applied in running equipment, which proves the feasibility of mentioned method.

Adaptive condition predictive-fuzzy PID optimal control of start-up process for pumped storage unit at low head area

2018 ◽  
Vol 177 ◽  
pp. 592-604 ◽  
Author(s):  
Yanhe Xu ◽  
Yang Zheng ◽  
Yi Du ◽  
Wen Yang ◽  
Xuyi Peng ◽  
...  
Keyword(s):  
Optimal Control ◽  
Fuzzy Pid ◽  
Storage Unit ◽  
Start Up ◽  
Low Head ◽  
Pumped Storage ◽  
Adaptive Condition ◽  
Head Area

scholarly journals Investigation on Dynamic Stresses of Pump-Turbine Runner during Start Up in Turbine Mode

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 499
Author(s):  
Funan Chen ◽  
Huili Bi ◽  
Soo-Hwang Ahn ◽  
Zhongyu Mao ◽  
Yongyao Luo ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Unsteady Flow ◽  
Cfd Simulation ◽  
Three Dimensional ◽  
Leading Edge ◽  
Complex Flow ◽  
Dynamic Stresses ◽  
Start Up ◽  
Pumped Storage ◽  
Turbine Mode

The startup process occurs frequently for pumped storage units. During this process, the rotating rate that changes rapidly and unsteady flow in runner cause the complex dynamic response of runner, sometimes even resonance. The sharp rise of stress and the large-amplitude dynamic stresses of runner will greatly shorten the fatigue life. Thus, the study of start-up process in turbine mode is critical to the safety operation. This paper introduced a method of coupling one dimensional (1D) pipeline calculation and three-dimensional computational dynamics (3D CFD) simulation to analyze transient unsteady flow in units and to obtain more accurate and reliable dynamic stresses results during start up process. According to the results, stress of the ring near fixed support increased quickly as rotating rate rose and became larger than at fillets of leading edge and band in the later stages of start-up. In addition, it was found that dynamic response can be caused by rotor stator interaction (RSI), but also could even be generated by the severe pressure fluctuation in clearance, which can also be a leading factor of dynamic stresses. This study will facilitate further estimation of dynamic stresses in complex flow and changing rotating rate cases, as well as fatigue analysis of runner during transient operation.

Transient thermo-elasto-hydrodynamic analysis of a bidirectional thrust bearing in start-up and shutdown processes

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jingwei Cao ◽  
Liming Zhai ◽  
Yongyao Luo ◽  
Soo-Hwang Ahn ◽  
Zhengwei Wang ◽  
...  
Keyword(s):  
Thrust Bearing ◽  
Stable Operation ◽  
Thermal Interaction ◽  
Lubrication Mechanism ◽  
Interaction Method ◽  
Storage Unit ◽  
Content Type ◽  
Start Up ◽  
Lubrication Characteristics ◽  
Pumped Storage

PurposeThe purpose of this paper is to reveal the transient thermo-elasto-hydrodynamic lubrication mechanism of a bidirectional thrust bearing in a pumped-storage unit, and to propose the transient simulation method of two-way fluid-solid-thermal interaction of thrust bearing.Design/methodology/approachThe transient fluid-solid-thermal interaction method is used to simulate the three-dimensional lubrication of the thrust bearing, during the start-up and shutdown process of a pumped storage unit. A pad including an oil hole is modelled to analyze the temporal variation of lubrication characteristics, such as the film pressure, thickness and temperature, during the transient operation process.FindingsThe injection of the high-pressure oil sufficiently affects the lubrication characteristics on film, in which the hysteresis phenomena were found between the start-up and shutdown possess.Originality/valueThis paper reveals the transient lubrication mechanism of tilting pad in a thrust bearing, by means of transient fluid-solid-thermal interaction method. Lubrication characteristics are simulated without assuming the temperature relationship between the oil film inlet and the outlet and the heat transfer on the pad free surface. This paper provides a theoretical basis for the safe design and stable operation of thrust bearings.

Study on the Flow Characteristics of Shengli Oilfield Super Heavy Oil

2017 ◽  
Vol 10 (1) ◽  
pp. 69-78 ◽  
Author(s):  
Wang Shou-long ◽  
Li Ai-fen ◽  
Peng Rui-gang ◽  
Yu Miao ◽  
Fu Shuai-shi
Keyword(s):  
Pressure Drop ◽  
Pressure Gradient ◽  
Heavy Oil ◽  
Flow Characteristics ◽  
Fluid Viscosity ◽  
Linear Flow ◽  
Start Up ◽  
Non Linear ◽  
Core Permeability ◽  
Velocity Pressure

Objective:The rheological properties of oil severely affect the determination of percolation theory, development program, production technology and oil-gathering and transferring process, especially for super heavy oil reservoirs. This paper illustrated the basic seepage morphology of super heavy oil in micro pores based on its rheological characteristics.Methods:The non-linear flow law and start-up pressure gradient of super heavy oil under irreducible water saturation at different temperatures were performed with different permeable sand packs. Meanwhile, the empirical formulas between start-up pressure gradient, the parameters describing the velocity-pressure drop curve and the ratio of gas permeability of a core to fluid viscosity were established.Results:The results demonstrate that temperature and core permeability have significant effect on the non-linear flow characteristics of super heavy oil. The relationship between start-up pressure gradient of oil, the parameters representing the velocity-pressure drop curve and the ratio of core permeability to fluid viscosity could be described as a power function.Conclusion:Above all, the quantitative description of the seepage law of super heavy oil reservoir was proposed in this paper, and finally the empirical diagram for determining the minimum and maximum start-up pressure of heavy oil with different viscosity in different permeable formations was obtained.

scholarly journals Turbine mode start-up simulation of a variable speed Francis pump-turbine prototype – Part II: 3-D unsteady CFD and FEM

2021 ◽  
Vol 774 (1) ◽  
pp. 012070
Author(s):  
D. Biner ◽  
S. Alligné ◽  
V. Hasmatuchi ◽  
C. Nicolet ◽  
N. Hugo ◽  
...  
Keyword(s):  
Variable Speed ◽  
Pump Turbine ◽  
Start Up ◽  
Turbine Mode

Cost advantage of adjustable-speed pumped storage unit for daily operation in distributed hybrid system

2021 ◽  
Author(s):  
Chen Feng ◽  
Yuan Zheng ◽  
Chaoshun Li ◽  
Zijun Mai ◽  
Wei Wu ◽  
...  
Keyword(s):  
Hybrid System ◽  
Cost Advantage ◽  
Storage Unit ◽  
Adjustable Speed ◽  
Pumped Storage

scholarly journals An experimental platform of variable speed pumped storage unit under wave disturbance: introduction and preliminary progress

2021 ◽  
Vol 774 (1) ◽  
pp. 012151
Author(s):  
Weijia Yang ◽  
Jiandong Yang ◽  
Wei Zeng ◽  
Zhigao Zhao ◽  
Guiqiao Zheng ◽  
...  
Keyword(s):  
Wave Disturbance ◽  
Variable Speed ◽  
Storage Unit ◽  
Experimental Platform ◽  
Pumped Storage

An Overall Control of Doubly fed Variable Speed Pumped Storage Unit in Pumping Mode

2020 ◽  
Author(s):  
Dinglin Li ◽  
Guoxian Gong ◽  
Jingliang Lv ◽  
Xinjian Jiang ◽  
Rufei He
Keyword(s):  
Variable Speed ◽  
Storage Unit ◽  
Pumping Mode ◽  
Doubly Fed ◽  
Pumped Storage
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