The Small Hydropower in China-A Focus of World Attention

This paper describes the present situation, construction experiences, existing problems and the principal tasks in the development of small hydropower in China.

Information acquisition technology for small hydropower stations in remote areas based on high-and low-orbit satellites

With a lack of coverage in private and public power communication networks,especially for collection of information from hydropower stations in remote areas,communication coverage is a significant issue.Satellite communication provides a large coverage area suitable for a variety of services and is less affected by geographical factors;moreover,the costs are independent of the communication distance.This study investigates information acquisition technology for small hydropower stations in remote areas using high-and low-orbit satellites.The information collection needs of small hydropower stations in remote areas are analyzed,and an information acquisition system is designed using high-and low-orbit satellites.For network security protection,network anomaly detection technology based on a support vector machine algorithm is proposed.The effectiveness of information collection was evaluated and verified for small hydropower plants in remote areas.The system provides technical support for“full coverage,full collection,and full monitoring”of the measurement automation information acquisition system.

Estimating Ecological Value of Small Hydropower Using Contingent Valuation Method:An Application to Tongjiqiao Reservoir in Zhejiang Province,China

The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an application of contingent valuation method(CVM) in rural China to estimate the willingness-to-pay(WTP) for environmental services provided by exiting hydropower station.Using the single-bounded and dichotomouschoice CVM,the ecological value of Tongjiqiao Reservoir(TJQR) is estimated,and the annual mean WTPs of single-bounded and double-bounded CVM estimation are 141.05 and 219.52 Yuan(RMB)/a,respectively.The 95% confidence interval of annual WTP on an average is 118.47,166.79 Yuan(RMB)/a and 204.41,236.22(Yuan RMB)/a,respectively.In contrast,double-bounded model could obtain much more information of WTP of the investigated,thus reducing the confidence interval of estimation,and enhancing the estimation accuracy of the WTP.According to the estimated mean WTP of the double-bounded CVM,the total ecosystem service value of the TJQR is 15.54 million Yuan(RMB).Compared with the conventional electricity of fossil power and large hydropower,the SHP will be less competitive in the absence of non-market value,ignoring that the environmental impacts of existing SHP will undermine the healthy development of clean energy sector.

Integrated Power Generation Scheduling Compilation Method for Large-scale Small Hydropower Station Group

针对小水电无序管理，弃水、窝电现象严重，水资源浪费问题突出的现状，设计省地一体化小水电发电计划编制方法。该方法规范了小水电计划编制流程，对发电计划实行分级制作与管理，增加了输电断面安全校核环节，并给出了超限断面计划调整方法，通过建议计划上报一输电断面校核一计划协调发布的闭环方式有效提高了发电计划的准确性和可操作性。该方法目前已应用于云南电网小水电管理系统，方法的科学性与有效性得到了实际工程的验证。

Load Frequency Control of Small Hydropower Plants Using One-Input Fuzzy PI Controller with Linear and Non-Linear Plant Model

This study presents an intelligent approach for load frequency control (LFC) of small hydropower plants (SHPs). The approach which is based on fuzzy logic (FL), takes into account the non-linearity of SHPs—something which is not possible using traditional controllers. Most intelligent methods use two- input fuzzy controllers, but because such controllers are expensive, there is economic interest in the relatively cheaper single-input controllers. A non- linear control model based on one-input fuzzy logic PI (FLPI) controller was developed and applied to control the non-linear SHP. Using MATLAB/Si- mulink SimScape, the SHP was simulated with linear and non-linear plant models. The performance of the FLPI controller was investigated and compared with that of the conventional PI/PID controller. Results show that the settling time for the FLPI controller is about 8 times shorter;while the overshoot is about 15 times smaller compared to the conventional PI/PID controller. Therefore, the FLPI controller performs better than the conventional PI/PID controller not only in meeting the LFC control objective but also in ensuring increased dynamic stability of SHPs.

Analysis of Flow Estimation Methods for Small Hydropower Schemes in Bua River

Any hydropower project requires an ample availability of stream flow data. Unfortunately, most of the hydropower projects especially small hydropower projects are conducted on ungauged river and consequently hydrologists have for a longtime used stream flow estimation methods using the mean annual flows to gauge rivers. Unfortunately flow estimation methods which include the runoff data method, area ratio method and the correlation flow methods employ a lot of assumptions which affect their uncertainty. This study was conducted on Bua River in Malawi to unveil the uncertainties of these flow estimation methods. The study was done on a well gauged catchment in order to highlight the variations between the observed, true stream flows and the estimated stream flows for uncertainty analysis. After regionalizing the homogenous sites, catchments using L-moments, an uncertainty analysis was done which showed that the area method is better followed by the correlating flow method and lastly the runoff data method in terms of bias, accuracy and uncertainty.

Assessment Framework of Green Intelligent Transformation of Small Hydropower in China

With the comprehensive promoted construction of the establishment of green small hydropower,the defects of existing small hydropower station are gradually emerging,and it is necessary to implement green intelligent transformation to promote the construction of energy internet in China.This study focuses on constructing a green intelligent planning and transforming assessment framework,and assists management department to filtrate the small hydropower stations which can be transformed reasonably.Firstly,power station economy,ecological environment,technical safety management and social benefits are involved in the assessment index system.Secondly,multi-expert judgment aggregation based on fuzzed comparison scale is put forward to calculate the index value,and evidence synthesis is used to comprehensively assess the feasibility of green and intelligent planning and transformation for several small hydropower stations.The simulation case analysis shows the constructed assessment framework can reflect the actual situation of objectives properly and would provide decision-making basis for green and intelligent planning and transformation of small hydropower stations.

Analysis of Switching Overvoltage in Regional Grid with Small Hydropower Plants

Present-day small hydropower plants (SHPs) have a large development potential because of the increasing interest in renewable resources and distributed energy generation, therefore, there are many SHPs in places of China where are rich in water resources. However, it has caused overvoltages in the distribution network, and which is even worse for the switching overvoltage such as isolated network operation, changing power supply path. The simple network model is used to analyze the reasons of the switching overvoltage, and the simulation software DIgSILENT/PowerFactory is used to check out the results of the theoretical analysis.

Environmental Integration of Small Hydropower Development

On the basis of cooperative research with European professionals, problems relating to environmental and ecological protection were discussed while small hydropower development in China currently was introduced in this paper. Guidelines of small hydropower development dealing with environmental protection were sug- gested hereby. Various specific technical environmental solutions focusing on small hydropower development applied in European and other developed countries were also introduced in this paper. Main environmental solutions are discussed as follows： integrated design should be advocated during plan/design stage,＂ ecohydraulic engineering and its utilization in SHP design and construction; effective technical approaches to relieve and eliminate the impact of river interception and fix the reasonable minimum biological flow; environment-friendly mitigation and compensation measures for high/low-head hydropower schemes applied in diversion works, intake, nature-like fish-passes, penstock and powerhouse design; study and application of the new technology, material and equipments; launching renovation of environmental protection in existing stations; emphasiz- ing public participation and their acceptability for the SHP environment; coordinated inter-disciplinary study at national level, etc. Two case studies in Sweden and Australia are given here.

Towards a Sustainable Development of Small Hydropower Plants, from Valley of Sperchios River to Mount Olympus

The mountainous region of Fthia, identified with the Valley of Sperchios River, in Central Greece, is rich in small watercourses and generously blessed with water and abundant water falls. The geographical configuration of Olympus and Fthia＇s mounts and the hydraulic singularities of drained lakes Askouris in Olympus, favour the installation of series of sustainable small hydroelectric plants. The present action consists of a serious effort towards the systematic sustainable small hydropower exploitation of Fthia＇s and Olympus hydraulic potential, including the Archimedean hydropower perspectives of Sperchios River.

小水电集约化运维管理三方演化博弈研究

“双碳”背景下,为推进小水电集约化运维管理,保证其高质量发展。基于演化博弈理论,构建小水电业主、政府与运维服务企业之间的三方博弈模型,并运用Matlab软件进行数值仿真分析,以探究小水电集约化运维管理三方策略选择的演化路径。结果表明:初始策略的变化对博弈三方演化收敛速度有显著影响;在一定条件下,博弈系统将演化稳定于较理想的均衡状态(1,0,1);运维成本效益、政府奖惩力度、运维平台智慧度和方案收费系数是影响小水电实现集约化运维管理的主要因素。研究结论可为小水电业主参与集约化运维管理和政府制定相关政策提供一定的理论指导。

广东省小水电绿色全要素智能管理存在的问题及对策

广东省农村小水电资源丰富,省内有近万座小水电,数量占居全国之首。小水电在解决农村用电、促进农村经济发展方面发挥了重要的作用,但是,随着技术进步和国家产业政策的调整、生态文明建设的推进,广东省小水电面临绿色转型、强化管理等需求,因此有必要分析小水电在绿色全要素智能管理方面存在的问题及对策。研究表明,广东省小水电存在安全生产有隐患、生态流量保障不足、运行管理自动化程度低、监管难等问题,可以通过建立安全生产标准机制、落实生态流量、促进小水电绿色转型、开展全要素智能管理等措施加以解决。

面向智慧化管理的数字孪生小水电工程建设技术研究

新阶段水利高质量发展对小水电发展提出了更高要求,亟须推进小水电智慧化管理,以加快推进实现小水电的绿色转型。阐述了我国小水电发展现状和面临的挑战,厘清了小水电智慧化管理需求,剖析了数字孪生小水电的内涵和特征;结合行业实际,提出当前我国数字孪生小水电系统基本框架和业务应用内容,解析行业内已开展的实践探索案例。针对建设行业标准、健全保障机制、加强科技支撑、推进先行先试提出建议,以期加速数字孪生技术在小水电领域的应用和推广。

小水电尾水水轮机转轮优化研究

【目的】为解决实际小水电站工程中尾水水轮机性能较差、运行效率较低的问题,缓解转轮叶片空化现象,【方法】设计了转轮桨叶倾斜角度分别为30°和45°的两种水轮机优化方案,并基于ANSYS仿真计算软件,在设计工况下对两种转轮设计方案进行了数值计算,同时对流场流态与模态分布计算结果进行了对比,根据两方案计算结果的整体流线分布、速度分布、压力分布及转轮区域涡量云图等开展流态分析,并进行干湿模态下的振型对比分析。【结果】结果显示:在设计工况下,转轮桨叶倾斜角度为45°时整体水流流态更加平稳、转轮区域压力分布更为均匀、旋涡更少,且预应力湿模态前五阶共振频率中最接近振动频率的数值仍存在40%的差异,工作环境中未产生共振现象,表明其整体性能较优。【结论】结果表明:数值模拟方法合理,模态分析与业界学者研究结果一致,所得数据具有可靠性。通过对转轮进行设计优化可提高水轮机抗空化、抗振等运行性能,对小水电站尾水水轮机优化设计提供有益参考,亦为类似工程问题改造提供了有效理论支撑。

基于景观格局指数的河流生境特征描述方法研究

以金沙江支流黑水河为研究对象,借助景观格局指数,筛选并建立描述生境特征的指标集,分析了黑水河苏家湾电站所处河段生境特征变化规律。研究结果表明:在不同工况下,生境斑块的时间和空间分布存在明显差异;主成分分析共提取出11个代表指标,从形状、聚集性、复杂性等方面描述了生境特征;筛选得到的生境指标集随流量变化存在4种不同的变化趋势,其中斑块占景观面积百分比、连接度、整体性和回旋半径加权面积指数与鱼类加权可用面积的变化显著相关。生境景观格局指数反映了鱼类生境斑块配置及其质量的变化,可为河流可持续发展和鱼类生境修复提供可靠的监测依据。

含小水电配电网重要负荷评估及其水光储优化配置方法

为保证含小水电配电网重要负荷的电能质量安全与稳定,发挥水光储系统互补作用,提出一种负荷重要程度评估方法和含小水电配电网重要负荷的水光储优化配置方法。首先,从用户角度出发,基于用电效益指标与用电体验指标2个维度建立负荷重要程度评估体系,采用G1熵权法量化用户节点的重要程度,确定重要负荷节点并将其作为光储接入备选节点,降低光储优化配置求解维度;其次,建立以水光储全寿命周期成本最小、电压偏差平方之和最小为目标的优化配置模型,引入规格化平面约束法求解两目标水光储优化配置问题,得到均匀的Pareto最优解集;然后,计算各解集综合偏移程度函数,得到最优折中解,作为优化配置最佳参考方案;最后,以改进的IEEE 33节点配电网为算例,证明所提的优化配置方法可以改善重要负荷的电压偏差,同时提高投资者的收益。

一种基于小信号模型分析的水电机组参与电网一次调频方法

由于水电机组自身复杂的动态特性,导致高比例水电在参与电网调频过程中易产生超低频振荡,不利于电网安全稳定运行。为此,提出一种基于小信号建模分析的水电机组参与电网调频方法。首先,为体现更贴近实际工作状态的动态特性,基于小信号分析对水电机组参与电网调频进行模型构建;然后,考虑到小信号模型会反映系统诸如超低频振荡等危害的发生特征,进而突出系统的非线性,进行分数阶PID(FOPID)控制器设计调速系统;在此基础上,利用遗传算法以频率偏差最小为目标进行控制器参数优化,以进一步改善控制效果。仿真分析表明,所建水电机组小信号模型能够准确反映水轮机的动态特性,同时性能优越的FOPID控制器能有效地抑制超低频振荡。

小型水电站开发和生态环境保护协调发展的问题探讨——以叶尔羌河小水电站为例

新疆位于中国西部,因其丰富的自然资源和特殊的生态环境而闻名。但是,该地区也面临着水资源短缺的严重问题。随着经济的发展和人口的增长,水资源的缺乏已成为制约新疆可持续发展的关键因素。特殊的内陆气候和地理位置使得水资源与生态保护之间的矛盾愈发激烈,进一步影响着生态稳定和经济进步。

基于水利新质生产力的小水电绿色发展

小水电是国际公认的清洁可再生能源。小水电绿色改造和现代化提升工作是贯彻“创新、协调、绿色、开放、共享”发展理念,加快转变小水电发展方式,推进水生态文明建设的必然选择,是发展水利新质生产力、实现提质增效升级的内在要求。我国小水电绿色开发的理念、经济实用的技术、价廉物美的设备、体系完整的标准等已领先世界;基于新质生产力的小水电绿色转型与发展,可为世界小水电可持续发展提供中国方案。

农村偏远地区梯级小水电站长期优化调度策略

为解决偏远农村附近梯级小水电站面临的经济效益少、调峰能力差、发电稳定低等复杂问题,提出一种改进蜜獾算法(Improved Honey Badger Algorithm, IHBA),在考虑上述问题和保证传统水力约束的同时加入迎峰度夏顶峰和自供区供电等特殊发电约束,进行多目标优化调度。首先,通过Fuch混沌映射进行初始化,保证初始解均匀分布。其次,在更新阶段引入黄金正弦、哈里斯鹰围攻和T分布扰动混合策略,增强寻优能力,提高搜索解的质量。然后,结合非支配排序和理想点法,解决多目标问题。最后,将IHBA应用于湖南某农村地区梯级小水电站调度中与实际结果进行比较。结果表明:从年发电量、保证出力和发电保证率3项指标综合考虑,所提方法能有效提高发电综合效益,且在改善自供区供电能力及迎峰度夏顶峰能力同时以抬高水头的形式增加上级水库型电站高效发电,减少下级径流式电站低效发电。