Grid-Connection Control of Small Hydropower Stations Based on the Principle of Quasi-Contemporaneous Grid-Connected

This present study deals with a new mechanical device consisting of a set of safety membranes, which has been successfully applied in several middle and small hydropower stations in China instead of a surge tank. Safety membranes are installed on the penstock near the powerhouse as controlled weak points. When the pressure caused by load rejection rises to the preset explosive value, one or more membranes rupture, protecting the penstock and the unit from damage. The device is simple, reliable and economical. The method of characteristics is employed to establish numerical model of safety membranes to simulate their rupture behavior, which is then introduced to investigate how to determine the number and diameter of membranes from two aspects, large fluctuation and hydraulic disturbance. The results show that the diameter of the membranes depends on the negative pressure along pipeline under hydraulic disturbance while the number of the membrane depends on the maximum water hammer pressure under large fluctuation during load rejection of the unit. The conclusion of membrane selection can perfect the present theory of safety membranes, and provide the theoretical guidance and practical basis for membrane device design and safety operation.

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Notice of Retraction: Design Wireless Data Transmission System for Small Hydropower Stations Based on nRF24L01

2009 First International Conference on Information Science and Engineering ◽

10.1109/icise.2009.492 ◽

2009 ◽

Cited By ~ 1

Author(s):

Hainan Long ◽

Zhiqiang Liu

Keyword(s):

Data Transmission ◽

Transmission System ◽

Wireless Data ◽

Small Hydropower ◽

Wireless Data Transmission ◽

Data Transmission System ◽

Hydropower Stations

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Influence of Surge Tank and Relief Valve on Transient Flow Behaviour in Hydropower Stations

ASME-JSME-KSME 2011 Joint Fluids Engineering Conference: Volume 1, Symposia – Parts A, B, C, and D ◽

10.1115/ajk2011-07034 ◽

2011 ◽

Cited By ~ 2

Author(s):

Alireza Riasi ◽

Ahmad Nourbakhsh

Keyword(s):

Power Plants ◽

Transient Flow ◽

Flow Analysis ◽

Internal Boundary ◽

Transient Condition ◽

Maximum Pressure ◽

Surge Tank ◽

Small Hydropower ◽

Relief Valve ◽

Hydropower Stations

Unsteady flow analysis in water power stations is one of the most important issues in order to predict undesirable pressure variations in waterways and also probable changes in rotor speed for the power plants safe operation. Installation of surge tank and relief valve is the two main methods for controlling of hydraulic transient. The relief valve is used in several medium and small hydropower stations instead of the surge tank and mounted on the penstock near the powerhouse. The recent generation of relief valves are reliable and beneficial and consist of fully control system that directly conducted by governor. This paper presents a numerical method for transient flow in hydropower stations using surge tank and relief valve. For this purpose the governing equations of transient flow in closed conduit are solved using the method of characteristics (MOC) using unsteady friction. Hydraulic turbine, surge tank and relief valve are considered as internal boundary conditions. The influence of surge tank and also relief valve on the maximum pressure in spiral case and turbine over speed has been studied for a real case. The results show that the transient condition is considerably improved by using a relief valve and this device can be mounted in lieu of an expensive surge tank.

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Logic Design of Improved Backup Power Automatic Switching Considering the Influence of Small Hydropower Stations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.1638 ◽

2012 ◽

Vol 463-464 ◽

pp. 1638-1642

Author(s):

Chen Jie Zhou ◽

Yi Xiong ◽

Liang Qin ◽

Xiao Ming Zha

Keyword(s):

Power Supply ◽

Power Grid ◽

Logic Design ◽

Small Hydropower ◽

Distributed Power ◽

The Stability ◽

Reliable Power Supply ◽

Hydropower Stations ◽

Small Capacity ◽

Automatic Switching

The correct and quick operation of backup power automatic switching（BPAS）devices is an effective guarantee of reliable power supply to the system. However, when transformer substations are connected to small-capacity distributed power like the local small hydropower stations, the conventional BPAS devices usually fail to get into operation, which leads to the loss of power in some parts of the system. To solve this shortage，this article comes up with an improved scheme of BPAS, which has been proved through PSCAD simulation to be effective in enhancing the stability and reliability of the power grid

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Study on generation capacity of small hydropower stations in distribution network

Indian Journal of Power and River Valley Development ◽

10.18311/ijprvd/2021/27302 ◽

2021 ◽

Vol 71 (1&2) ◽

pp. 5

Author(s):

Genghuang Yang ◽

Wenbin Sun ◽

Xiayi Hao ◽

Yingmei Zhang ◽

Li Yang ◽

...

Keyword(s):

Power System ◽

Distribution Network ◽

Relay Protection ◽

Hydropower Station ◽

Small Hydropower ◽

Current Variation ◽

Generation Capacity ◽

The Difference ◽

Hydropower Stations

Small hydropower station, when producing power energy to power system through the distribution network, may lead to the change of the detected current in relay protection and the protection coverage. In this paper, IEEE7 based network is formed in the platform of PSCAD/EMTDC to analyze the effects of distribution network in current protection when a small hydropower station is linked in. The running of relay protection in Section I and II is simulated to obtain the difference of current variation of network with or without small hydropower station. Also the key parameters are calculated to point out the maximum generation capacity of the small hydropower station in case of reliable and sensitive current protection.

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Design and implementation of PLC based reclosing device on synchronization line of small hydropower stations

2016 IEEE International Conference on Power and Renewable Energy (ICPRE) ◽

10.1109/icpre.2016.7871220 ◽

2016 ◽

Author(s):

Yang Genghuang ◽

Wang Jiguang ◽

Su Xin ◽

Sun Wenbin

Keyword(s):

Small Hydropower ◽

Design And Implementation ◽

Hydropower Stations

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Application of Fuzzy Recognition Model for the Diversion Structures Safety Evaluation at Small Hydropower Stations

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.687-691.3686 ◽

2014 ◽

Vol 687-691 ◽

pp. 3686-3690

Author(s):

Ming Li ◽

Xue Feng Yu ◽

Yuan Dong Wei

Keyword(s):

Safety Evaluation ◽

Hydropower Station ◽

Hydroelectric Power Station ◽

Hydroelectric Power ◽

Power Station ◽

Small Hydropower ◽

Recognition Model ◽

Fuzzy Recognition ◽

Hydropower Stations

In this passage is about the safety evaluation on the conveyance structure of small hydroelectric power station. Applying Binary comparative indicators to determine the weights and fuzzy recognition model on the conveyance structure of small hydroelectric power station’s assessment. Compared other models with fuzzy recognition model which will be explained in detail in the next section on a specific small hydropower station. The results show that the fuzzy recognition model is feasible and effective on safety evaluation on the conveyance structure of the hydroelectric power station.

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The Application of Safety Membranes in Hydropower Plant

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.607.449 ◽

2014 ◽

Vol 607 ◽

pp. 449-453

Author(s):

Sheng Chen ◽

Jian Zhang ◽

Xiao Dong Yu

Keyword(s):

Hydropower Plant ◽

Mechanical Device ◽

Surge Tank ◽

Small Hydropower ◽

Membrane Rupture ◽

Rupture Pressure ◽

Hydropower Stations ◽

The Mathematical Model ◽

Rupture Behavior

Safety membrane is a good mechanical device that can be applied in middle and small hydropower stations instead of a surge tank. This present study deals with the determination of three most important parameters of safety membrane, rupture pressure, diameter, and number. The mathematical model of transient process is established by introducing the method of characteristic, which is used for the simulation of the rupture behavior of safety membrane. Then the model is applied to a specific hydropower station that only can employ safety membrane as the regulating measurement, and it shows good performance. The achievements of the study can serve as a reference for similar projects.

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