Simulation of Underground Reservoir Stability of Pumped Storage Power Station Based on Fluid-Structure Coupling

Based on global initiatives such as the clean energy transition and the development of renewable energy,the pumped storage power station has become a new and significant way of energy storage and regulation,and its construction environment is more complex than that of a traditional reservoir.In particular,the stability of the rock strata in the underground reservoirs is affected by the seepage pressure and rock stress,which presents some challenges in achieving engineering safety and stability.Using the advantages of the numerical simulation method in dealing deal with nonlinear problems in engineering stability,in this study,the stability of the underground reservoir of the Shidangshan(SDS)pumped storage power station was numerically calculated and quantitatively analyzed based on fluid-structure coupling theory,providing an important reference for the safe operation and management of the underground reservoir.First,using the COMSOL software,a suitablemechanicalmodel was created in accordance with the geological structure and project characteristics of the underground reservoir.Next,the characteristics of the stress field,displacement field,and seepage field after excavation of the underground reservoir were simulated in light of the seepage effect of groundwater on the nearby rock of the underground reservoir.Finally,based on the construction specifications and Molar-Coulomb criterion,a thorough evaluation of the stability of the underground reservoir was performed through simulation of the filling and discharge conditions and anti-seepage strengthening measures.The findings demonstrate that the numerical simulation results have a certain level of reliability and are in accordance with the stress measured in the project area.The underground reservoir excavation resulted in a maximum displacement value of the rock mass around the caverns of 3.56 mm in a typical section,and the safety coefficient of the parts,as determined using the Molar-Coulomb criterion,was higher than 1,indicating that the project as a whole is in a stable state.

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.

Equivalent Substitution Based Method for Calculation of Best Installed Capacity of Pumped Storage Power Station

This paper proposes a novel method to calculate the best installed capacity of pumped storage power station. First, we choose the day with maximum load as the typical day for every month and simulate the system running in two cases of whether the pumped storage power station is put into operation. The difference of the total coal consumption between the two cases is the peak load shifting benefit. Furthermore, we build load model and power generation model to calculate the benefit of emergency use and frequency modulation, which are the major projects of dynamic benefits. At last, on the premise of ensuring the system requirements, the developed method employs the maximum benefit of the unit capacity as the objective function to get the best installed capacity of pumped storage power station by simulations. Tests on a provincial power grid have shown that the developed method which combines of load characteristics, electric structure and other factors can get the best installed capacity of pumped storage power station easily and has a certain guiding significance for the planning and construction of the pumped storage power station.

Optimal Dispatching Model Considering the Pumped Sto-rage Power Plant in Hunan

This paper made a research on the Intelligent Optimization Operating Modeling of Pumped Storage Power Station in Hunan Power Grid. First it introduces the characteristics of Hunan power grid and analysis the practical requirement of dispatching. Then it brings forward the intelligent optimization model and set up running model for pumped storage power station of Hei Mi-feng. At last, it introduces the application of pumped storage power station in Hunan power grid and proves the effectiveness of the optimization models.

基于组合赋权-云模型的抽蓄电站高质量发展评价体系

为科学评价生产期抽蓄电站高质量发展现状、把握电站发展的薄弱环节、明确建设期及新投运电站发展方向,根据抽蓄电站定位及高质量发展内涵,经过2轮筛选,构建了包含服务电力系统稳定运行、经济、绿色、创新、共享5个一级指标以及18个二级指标的评价指标体系;选用层次分析法–决策实验分析方法确定指标权重,运用云模型评价各电站高质量发展等级。最后,选取A抽蓄电站为算例验证评价体系适用性。评价结果显示,该电站服务电力系统稳定运行、绿色和共享3个指标表现均为良好,经济和创新指标表现为中等,与电站实际运行情况相符合。该验证结果表明,采用上述方法构建的评价指标体系有很好的适用性。

抽蓄电站全库盆防渗水库渗流缺陷影响分析

针对抽蓄电站全库盆防渗水库土工膜缺陷导致水库渗流量产生变化的安全问题,结合陕西省某抽蓄电站水库库底土工膜防渗工程,采用单因素影响分析和多因素影响分析方法进行抽蓄电站全库盆防渗水库渗流缺陷影响分析。结果表明,水头大小、缺陷大小、缺陷个数均正向影响抽蓄水库渗流量,而缺陷位置与抽蓄水库渗流量的相关性不明显。其中缺陷大小是影响抽蓄水库渗流量的主要因素,其次为水头大小,再次为缺陷个数。

含废旧矿井抽蓄电站的源-荷-储协同控制调频研究

针对新能源在电网中渗透率不断提高导致系统调频容量和频率响应能力不足的问题,提出一种含废旧矿井抽蓄电站的源-荷-储协同控制调频方法。首先,建立了电解铝工业负荷、废旧矿井抽蓄电站和超级电容频率响应模型。然后,基于模型预测控制理论,以系统状态量和控制量的加权函数最小为目标,设计区域信息互动的分布式模型预测控制器,并提出含废旧矿井抽蓄电站的源-荷-储协同控制调频方法。最后,将分布式模型预测控制器应用在所提源-荷-储协同控制方法中,并在改进的IEEE标准两区域LFC模型中进行仿真。结果表明所提方法可以缩短频率恢复时间,减小最大频差值,改善系统调频动态性能。

考虑动态摩阻的抽水蓄能电站水力瞬变建模模拟

针对抽水蓄能电站管道内水力瞬变问题,考虑动态摩阻,采用二阶有限体积法(FVM)Godunov格式进行数值建模与模拟.首先根据有限体积法将控制方程进行离散,通量计算用Riemann求解器.机组全特性曲线采用改进的Suter变换,在计算中分别考虑Brunone与TVB动态摩阻模型,将计算结果与恒定摩阻和试验值进行对比,并进行了相应的参数敏感性分析.结果表明,在抽水蓄能电站管路模型中,动态摩阻模型仅增加了管道内后续波动的衰减,对于初始波动几乎没有影响.在单管中,动态摩阻的影响随着关阀时间的缩短而增大;而在抽水蓄能电站系统中由于雷诺数较大,动态摩阻模型的适用性较差,对于各项物理参数的变化均不敏感.这表明在大管径、高流速的输水工程中,可忽略动态摩阻的影响,但对于小管径、低流速的工程,有必要考虑动态摩阻的影响.

发电机轴承油槽密封结构对油雾泄漏的影响

大型水电站轴承油槽总是不可避免地发生油雾泄漏问题,改善密封结构通常是解决水电站轴承油槽甩油雾问题最简单有效的措施.为了降低油雾泄漏对发电机内部造成的污染,文中围绕某抽水蓄能电站发电机轴承油槽甩油雾问题,对油槽密封盖进行改型,并开展密封腔油雾多相流数值模拟研究.通过Mixture模型和SST k-ω模型解析了原密封结构和2种改进密封结构的流场分布特性,并评估了不同密封结构下的油雾泄漏情况.研究结果表明:相比于原设计模型,改进模型Ⅰ,Ⅱ的油雾泄漏量平均减少了18.9%,88.6%,改进模型Ⅱ抑制油雾效果最为显著;高压气体的注入会破坏密封腔原有的环形涡流,从而抑制油雾逸出;对于下部密封腔而言,提高进口压力,减小进口流速都有助于改善密封性能.文中的研究可为油槽密封改良以及轴承油雾泄漏控制措施提供一定的参考,提升电站的经济效益以及运行的安全稳定性.

抽水蓄能电站输水管道区域环境振动分析及减振措施

为了探讨抽水蓄能电站输水管道区域环境振动的问题,结合实际工程的环境振动监测资料,采用Midas-GTS软件分析抽水蓄能电站输水管道区域环境在不同工况下的振动影响,并提出合理的减振措施。研究结果表明:库区上游靠近机组的区域环境振动分贝值均大于库区下游,库区下游靠近居民区的环境振动分贝值均大于居民区环境振动标准值,且严重影响居民的正常生活。由于抽水蓄能电站区域环境振源复杂,填充沟措施效果显著,且易施工,对类似的抽水蓄能电站工程具有一定的借鉴意义。

多交易模式下混合式抽水蓄能电站优化调控策略

“双碳”目标下,实现常规水电与抽水蓄能二者功能结合的混合式抽水蓄能电站是水力发电的新趋势,而如何制定合理的调控策略是混合式抽水蓄能适应电力市场发展的关键难点。因此,提出了一种适用于混合式抽水蓄能电站的多交易运行模式,同时根据常规水电与抽水蓄能的特点提出了混合式抽蓄电站内部协同调控方法。多交易模式下混合式抽水蓄能的常规水电部分实行峰谷电价结算、抽水蓄能部分实行两部制电价结算,同时允许电站保留容量电费参与日前现货市场出清。基于该运行模式和调控方法,以混合式抽水蓄能电站利润最大化和社会福利最大化为目标提出了双层优化调控模型。最后通过算例分析证明了所提模型的有效性,同时分析结果表明所提混合式抽水蓄能调控策略有利于实现水电资源的合理利用,对比不同单一交易运行模式电站利润至少提高1.2%。

抽水蓄能电站水库岩质边坡消落带生态修复探讨

抽水蓄能电站是我国水利水电开发的重要组成部分,建成运行后将形成库水周期性涨落的消落带,生境条件极为脆弱,是生态环境修复的重难点区域。对岩质边坡生态修复关键技术和水库消落带生境改善方法开展系统分析,结合河南天池抽水蓄能电站上水库岩质边坡消落带生境特征,提出土工格室+生态袋+挂网复合工程技术可作为水库岩质边坡消落带生态治理的关键措施。基于消落带库水涨落节律和植物自身遗传特性,指出消落带下端优先配置长期耐淹多年生草本植物(如狗牙根),消落带中端配置耐淹能力较强的灌木和草本(如秋华柳、黄荆、紫穗槐、中华蚊母和狗牙根等),消落带上端可综合配置抗旱耐淹能力较好的乔木、灌木和草本(如银合欢、桑树、紫穗槐、黄荆、秋华柳、狗牙根和苘麻等),以及生态适应性较强的乡土植物(如藜和诸葛菜等)。研究成果对抽水蓄能电站水库岩质边坡消落带生态治理具有重要指导意义。

水轮机调节系统与轴系耦合模型对系统参数的敏感性分析

抽水蓄能电站频繁地暂态过程对轴系振动有重要影响,建立一个能够反映水电机组暂态响应的调节系统与轴系的耦合模型对于研究抽水蓄能电站的安全运行至关重要。以拉日朗日公式推导的扭矩方程为纽带,构建了水轮发电机组调节系统与考虑多振动诱发因素的轴系系统的瞬态耦合模型。计算了甩不同负荷下轴系的动态响应过程,分析了发电机偏心质量以及发电机励磁电流对轴系暂态过程的影响。研究发现,甩去的负荷越多,轴系在动态响应的过程中振动越剧烈,甩30%负荷,甩60%负荷,以及甩100%负荷后,发电机转子在x方向上的振幅较甩负荷前分别增加了68.7%,109.3%,以及126.3%。发电机的偏心质量越大,水轮发电机组轴系在动态响应过程中的幅值越高,系统越不稳定,而励磁电流越大,轴系在响应过程中的幅值越小,越有利于系统稳定运行。本文的目的是为水轮发电机组调速系统-轴系系统瞬态耦合模型的建立提供一种方法,探讨和评价甩负荷下瞬态耦合模型的参数敏感性,保障机组暂态下的安全稳定运行。

电力市场环境下抽水蓄能电站容量电费定价与成本分摊方法

抽水蓄能电站作为一种有效的电力系统灵活性资源,将成为保障新型电力系统安全稳定运行的重要手段。制定合理的回收抽水蓄能电站建设固定成本方案是支撑系统运行、激励投资的关键问题。在抽水蓄能电站的市场化运行背景下,构建了抽水蓄能电站顺次参与现货-辅助服务市场的容量电费定价模型,实现以经营期内收支平衡为目标定期滚动核定抽水蓄能电站的待分摊成本。同时,考虑抽水蓄能电站容量电费的潜在分摊对象,提出采用效用比例VCG(Vickrey-Clarke-Groves)机制对抽水蓄能电站容量电费进行成本分摊,量化源荷侧分摊主体的替代效益,并将容量电费按比例分摊。实际系统算例的仿真分析验证了所提方法的有效性。

水泵水轮机S特性对相继甩尾水最小压力的影响

为探究水泵水轮机全特性曲线S特性与尾水压力最小值的联系,基于新丰抽水蓄能电站的过渡过程数值仿真模型模拟了尾水最不利相继甩工况。通过调整机组运行轨迹线附近开度线斜率,对比分析并总结S区形状变化对相继甩工况尾水压力极值的影响规律,提出了一种图形指标,能够应用在抽蓄前期设计中评价S特性对尾水压力影响优劣,并验证其准确性。结果表明,相继甩工况后甩机组流量变化率第一波下降时,机组运行轨迹线呈现完整倒S形,S区形状变化改变了机组流量变化率的大小,导致出现在靠近轨迹线S形下拐点前的尾水压力极值发生变化,给出的图形指标形状越趋近于竖向细长的规则长方形,相应的尾水最小压力的改善效果越好。

湖南省桂阳抽水蓄能电站高压引水隧洞稳定性分析

为研究湖南桂阳抽水蓄能电站高压引水隧洞稳定性,在工程区开展了高压压水试验和地应力测试,定量描述了隧洞围岩在高内水压力作用下的渗透特性,分析了整个工程区特别是重要工程部位的岩体应力状态,在此基础上根据围岩条件、抗抬理论准则、最小主应力准则、渗透准则评价了高压引水隧洞的渗透稳定性。结果表明:(1)工程区水平主应力大小总体上随深度的增加而增大,3个主应力之间的关系为SH>SZ>Sh,属于走滑型应力状态,钻孔附近地壳浅表层的最大水平主应力方位平均为NW32°,高压岔管及厂房区域属中等-低地应力区。高压压水试验结果显示隧洞围岩属于弱至微透水岩体;(2)高压引水隧洞各洞段具有足够的埋深条件,满足抗抬理论准则,同时隧洞围岩的抗渗透能力及抗水力劈裂能力均较好,基本满足钢筋混凝土衬砌方案的要求。

大型抽水蓄能电站地下厂房结构自振特性分析

自振特性分析是抽水蓄能电站地下厂房结构振动研究的基础。以丰宁抽水蓄能电站地下厂房为计算实例,建立了变速机组段地下厂房结构的三维有限元模型。首先采用模态分析方法研究了不同边界条件对地下厂房整体结构及楼板、立柱、楼梯、风罩和机墩等局部结构自振特性的影响,然后分析了丰宁地下厂房可能存在的振源,并对厂房整体及局部结构进行了共振复核。结果表明,上下游边墙弹簧约束条件的增强可以有效提高厂房整体结构自振频率,但对楼板局部自振频率的大小影响不大,对楼梯自振频率也无影响。固定边界使厂房整体结构各阶自振频率显著增大,对楼板、立柱、风罩和机墩等局部结构自振频率影响也较大。在可能的振源作用下,厂房整体结构和各局部结构发生共振的可能性很小。

可水力短路运行的三机式抽蓄机组研究综述

“双碳”发展目标的提出对电力系统中灵活调节电源的需求更为迫切。抽水蓄能电站作为当前电网中应用规模最大、技术最成熟的灵活调节电源,广泛使用的可逆式机组存在抽水工况功率不可调节的问题,限制了抽蓄电站的运行灵活性。研究证实采用三机式抽蓄机组水力短路运行可实现在抽水运行时的快速功率调节,更灵活的平衡间歇性清洁能源并网对电网的扰动,具备常规抽蓄机组所不具备的显著优势,是增强服务新型电力系统的有效手段。但具备水力短路运行模式的三机式机组在国内外仅有几个电站的应用示范,其研究在各国均处于起步阶段。我国仅有九十年代投产的羊湖电站采用了三机式机组,且由于多种原因一直未真正实现抽水调节运行。为提高新能源为主电网的灵活性,国外近年来加大了对三机式机组的研究和应用。为推动未来我国对三机式抽蓄机组的研究及应用,本文介绍了三机式机组的特点及国内外研究应用现状,对当前推动三机式机组技术应用面临的难题进行了梳理,提出了后续亟待解决的关键技术问题,可为后续开展相关研究提供参考。

不同市场环境下贵州省抽水蓄能电站的电价形成机制研究

在梳理我国抽水蓄能电站电价政策演变历程的基础上,针对贵州省电力市场的发展方向,制定了针对贵州省乌江流域抽水蓄能电站在不同电力市场环境下的电价形成机制,分别对现货市场形成前后电力市场环境下的电量电价和容量电价进行测算。结果表明,在不完善的电力市场环境下电站上网电价为0.351 5元/(kW·h),抽水电价为0.263 6元/(kW·h),站点容量电价为668.50~771.70元/(kW·a);在较完善的电力市场环境下峰谷电价差为0.331~0.504元/(kW·h),站点容量电价为586.17~689.37元/(kW·a),可认为现阶段未形成现货市场的情况下严格执行两部制电价是合理有效的,未来形成现货市场后将由市场竞争生成电价。