水库发电优化调度模型的对比研究

水电发电效益是水库调度的核心内容。为了寻求满意的发电效益,在考虑水电站水库自身约束和系统调峰要求,建立以系统发电效益最大为目标的优化调度模型,并通过乌江渡水库实例计算,对发电量最大和发电效益最大两种优化调度模型进行对比分析。结果表明:后者较前者更符合实际。     

基于和声搜索算法的水库发电优化调度研究

为提高水电厂发电效益,综合运用和声搜索算法,提出单级水库的优化调度方法,即首先分析单级水库优化调度约束条件,然后以月末水位为自变量建立基于年发电量最大原则的水库优化调度模型,最后运用和声搜索算法模拟水库调度。实例应用结果表明,基于和声搜索算法的优化结果较多年实际最大发电量及遗传算法的优化结果分别提高了8.69%、1.55%。     

基于改进多目标蝙蝠算法的洛河流域水库优化调度

为了发挥水资源综合利用的最大效益,实现水库发电和供水效益双赢的优化调度需求,以水库发电量最大和水库下游用水区域总缺水量最小为目标建立了多目标优化调度模型。同时,提出改进多目标蝙蝠算法(IMOBA)用于求解多目标优化调度模型,该算法引入外部精英蝙蝠集EBS()来存储算法寻优过程中的非劣解,设计一种基于混沌原理的脉冲发射率生成机制来增强算法的搜索能力,并加入变异操作以提高算法的种群多样性。将改进多目标蝙蝠算法应用在洛河流域故县水库,得到丰、平、枯三种典型年下的故县水库调度方案集。结果表明,IMOBA算法合理有效且优于多目标蝙蝠算法(MOBA),能较好地反映洛河流域故县水库的发电和供水要求。同时验证了多目标优化调度模型的可行性,为流域水库多目标优化调度方案的制定提供了新途径。     

金沙江下游梯级与三峡梯级水库联合发电调度

针对金沙江下游梯级水库的相继建成将会改变长江流域梯级水库综合调度格局问题,构建了金沙江下游梯级水库与三峡梯级水库联合发电调度模型,并采用逐次优化算法进行了求解.结果表明,采用联合优化调度后整个梯级发电效益明显,与原设计方案相比梯级平均发电量可增加6.29;与各梯级单独优化运行相比,梯级发电量可增加1.48%.     

三种水库优化调度方案实施模式的对比研究

为研究水库优化调度方案在水位、流量及出力控制模式下的实施效果,以发电量最大为目标建立优化调度模型并求解,选取发电效益、水位越限风险率及弃水量构建评价指标体系,对不同水库运行工况下的调度方案实施过程进行仿真计算,并评价其实施效果。小漩水电站的实例应用结果表明,水位控制模式对应的水位越限风险率最低,但弃水量最大导致其发电效益最差;流量控制模式与出力控制模式对应的水位越限风险率相差不大,但出力控制模式弃水量更少,发电效益更高。因此,出力控制模式可作为调度方案实施过程中的首选模式。     

基于分时电价的水库调度图优化研究

以芹山水库为例,结合分时电价原理与水库优化调度理论,划分了分时电价的时段,建立了考虑电价的以水电站水库发电效益最大为目标、兼顾保证出力要求的优化调度模型,应用改进的遗传算法优化水库常规调度图.结果表明,考虑分时电价影响后平均出力变小,能多发峰电,增加发电效益.     

白莲河水库常规发电调度图的优化研究

水库常规发电调度图简单直观、操作方便,但其制订的理论基础不够扎实,调度效果不理想。为了对常规发电调度图进行优化,使其更好地指导水库的实际运行,以白莲河多年调节水库为例,以发电量最大为目标建立数学模型,进行长系列径流资料的优化计算,得到确定性优化运行轨迹。优化轨迹与常规发电调度图配合组成优化空间,在此空间内对常规发电调度图进行优化。模拟结果表明,与常规发电调度图相比,优化后的常规发电调度图各项运行指标均有较大幅度的提高,优化效果较好,可指导水库实际运行。     

权衡生态和发电目标的梯级水库强化学习模型及其应用

为更好地发挥经济及生态效益,建立了基于强化学习算法的梯级水库优化调度模型,以周尺度小浪底天然入库流量过程为基础,探讨梯级水库发电与生态目标之间的权衡,并将该模型应用于小浪底-西霞院梯级水库中,分别探讨了不同调度方案下发电最优、生态最优和发电-生态权衡的优化调度策略。结果表明,以发电最优为目标时,梯级水库多年平均发电量比常规调度增加了3.62%～7.92%;以生态最优为目标时,平均生态保证率比常规调度增加了31.68%～33.66%。结果为梯级水库多目标优化调度提供了一种可行方法。     

考虑动态出力系数的某水库优化调度模型及应用

针对综合出力系数是水电站高效运行的重要动态参数且现有研究中多采用定值、过于理想化的问题,建立考虑厂内经济运行和动态出力系数的某水库优化调度模型,并应用遗传算法求解。对某水库的优化调度结果表明,采用动态出力系数的优化调度模型效益提升相较于定出力系数更优,发电效益最大可提升5.15%,达到了高效发电的目标,可为水库日常调度提供参考。     

考虑动态出力系数的某水库优化调度模型及应用

针对综合出力系数是水电站高效运行的重要动态参数且现有研究中多采用定值、过于理想化的问题,建立考虑厂内经济运行和动态出力系数的某水库优化调度模型,并应用遗传算法求解。对某水库的优化调度结果表明,采用动态出力系数的优化调度模型效益提升相较于定出力系数更优,发电效益最大可提升5.15%,达到了高效发电的目标,可为水库日常调度提供参考。     

基于多随机变量风险约束的水电站长期优化调度

针对市场环境下水电站如何综合考虑电价和来水等不确定性因素下的优化调度是当前研究的热点和难点,建立了考虑电价和来水等不确定性因素的风险约束水电站长期优化调度模型。根据此模型发电商可方便地在预期的目标收益和风险之间进行权衡,达到以较小的风险获得较大的收益的目的。以二滩电厂实算为例,表明了该模型的有效性。     

Contribution of pumped hydro storage to integration of wind power in Kenya: An optimal control approach

This paper investigates the benefit of optimally integrating wind power in Kenya with pumped hydro storage. The approach includes development of an optimal control strategy to deploy paired wind and pumped hydro storage resources, for the Lake Turkana Wind Power project. The stochastic model, which maximizes expected revenue over the planning horizon, is developed taking into the consideration the structure and running of the Kenya electricity market. The 300 MW Lake Turkana Wind Power wind farm is simulated using wind speed data from Marsabit, which is in close proximity to the Lake Turkana region. From the simulation of the wind farm, we find that the daily pattern exhibited by the wind speeds, does not match the average daily load pattern. Pumped hydro storage reduces the systems total power output shortage by 46%. This approach to operation could alleviate the significant economic burden of the take-or-pay purchase agreement that led to the removal of financial backing of the project by the World Bank. The use of pumped hydro storage in conjunction with the wind farm is also found to increase the expected daily revenue of the wind farm by over ten thousand dollars.     

风电-抽水蓄能联合系统的优化运行研究

抽水蓄能和风力发电互补系统可以有效抑制风电功率的波动,为电网提供优质电能.为了确定各时段的风力发电机和抽水蓄能电站的出力状态,实现优化控制,文中从经济效益、电能质量和综合效益3个角度建立了优化模型,并利用遗传算法进行仿真计算.仿真结果表明：经济效益模型可以实现最大经济效益运行,对风电波动有一定抑制作用;电能质量模型可以使互补系统的输出功率平滑,输出功率标准差很小,但是经济效益会下降;综合效益模型考虑了电能质量的约束条件,在满足电能质量要求的前提下,实现最大经济效益运行,是综合考虑电能质量和经济效益后的一种优化运行策略.     

On the economics of ramping rate restrictions at hydro power plants: Balancing profitability and environmental costs

This paper examines the impact of ramping rate restrictions imposed on hydro operations to protect aquatic ecosystems. A dynamic optimization model of the profit maximizing decisions of a hydro operator is solved for various restrictions on water flow, using data for a representative hydro operation in Ontario. Profits are negatively affected, but for a range of restrictions the impact is not large. Ramping restrictions cause a redistribution of hydro production over a given day, which can result in an increase in total hydro power produced. This affects the need for power from other sources with consequent environmental impacts.     

计及绿色电力证书与碳交易制度的“源-荷”协调优化调度

基于低碳电力和智能电网的背景,考虑现有的风电消纳困境,该文以绿色电力证书为基础,结合碳排放权的交易制度,同时引入需求侧高载能企业负荷的响应模型,并将虚拟电厂经济效益作为优化目标函数,建立以绿证交易为基础,结合碳交易制度和高载能需求侧响应的“源-荷”双侧互补协调优化调度模型。最后将某省份区域电网代入到该文所构建模型之中进行仿真,并采用自适应免疫疫苗算法对模型进行求解,结果表明所建立的计及绿证交易与碳交易的模型有利于促进风电消耗,降低单位发电量的碳排放。     

Power system optimization

Long-term gas purchase contracts usually determine delivery and payment for gas on the regular hourly basis, independently of demand side consumption. In order to use fuel gas in an economically viable way, optimization of gas distribution for covering consumption must be introduced. In this paper, a mathematical model of the electric utility system which is used for optimization of gas distribution over electric generators is presented. The utility system comprises installed capacity of 1500 MW of thermal power plants, 400 MW of combined heat and power plants, 330 MW of a nuclear power plant and 1600 MW of hydro power plants. Based on known demand curve the optimization model selects plants according to the prescribed criteria. Firstly it engages run-of-river hydro plants, then the public cogeneration plants, the nuclear plant and thermal power plants. Storage hydro plants are used for covering peak load consumption. In case of shortage of installed capacity, the cross-border purchase is allowed. Usage of dual fuel equipment (gas–oil), which is available in some thermal plants, is also controlled by the optimization procedure. It is shown that by using such a model it is possible to properly plan the amount of fuel gas which will be contracted. The contracted amount can easily be distributed over generators efficiently and without losses (no breaks in delivery). The model helps in optimizing of fuel gas–oil ratio for plants with combined burners and enables planning of power plants overhauls over a year in a viable and efficient way.     

基于改进粒子群算法的风光水互补发电系统短期调峰优化调度

风光水互补发电系统优化调度需要考虑风光电源的间歇性及波动性,同时还要处理梯级水库复杂的水力联系及不同电源之间的电力联系,因而建立风光水互补发电系统短期调峰优化调度模型,并采用粒子群算法进行求解,针对粒子群算法的早熟及后期收敛速度慢等问题,从惯性因子和种群拓扑结构两方面对粒子群算法进行改进,并对福建省电力调控中心管辖的12座常规水电站、木兰溪1座抽水蓄能电站、31座风电场、5座光伏电站组成的风光水多种电源互补系统进行数值分析。结果表明,所建模型能较好地实现对电网负荷的削峰填谷,所提算法显著提高了求解效率和求解质量,是一种解决风光水互补发电系统短期联合优化调峰调度实用性很强的有效算法。     

基于多目标的独立微电网电源容量优化设计

针对独立型水-光-柴-储微电网,综合考虑经济性、环境效益和供电可靠性,提出了微电网的电源容量多目标优化配置模型,即采用粒子群优化算法在一定的控制策略下对所提出的电源容量多目标优化配置模型进行求解,得到微网系统中储能装置和各分布式电源的容量。以我国西藏某地区为算例对微电网进行电源容量优化设计,通过对模型求解结果与柴油发电机单一供电计算结果及单目标容量优化结果的对比分析,验证了所提模型的合理性和优越性。     

Nordic hydropower flexibility and transmission expansion to support integration of North European wind power

The expected increase of wind power production in the North and Baltic Seas will substantially increase the variability of the generation portfolio in Northern Europe. Access to available resources of flexible power production will be necessary to support the power system against this variability. Since the Nordic hydro‐based power system can provide such resources, a stronger interconnection between continental Europe and the Nordic region seems to be beneficial. This paper assesses the challenges related to wind power production variability, especially offshore, in the North and Baltic Seas. Assessment on the transmission grid needed for both harvesting the available wind production located far away from load centres and to enable the optimal use of hydropower flexibility is studied in a long‐term cost‐benefit analysis. Special focus is devoted to the role of an offshore grid structure and the impact of onshore grid constraints. The analysis includes two interrelated simulation steps. The first step focuses on the strategic use of hydro energy in the day‐ahead market, where detailed modelling of water courses and hydro production in the Nordic region is considered. Then, in a second step, flow‐based simulations are conducted on a detailed grid model for the whole European system. The results show that long‐term strategies for the expansion of offshore and onshore grids must be defined in a coordinated way to ensure optimal developments. Copyright © 2014 John Wiley & Sons, Ltd.