计及负荷损失费用的含风电场发输电系统可靠性评估

风能具有随机性和间歇性的特点,风电场的存在会对电力系统可靠性产生一定的影响。对于含有风电场的发输电系统,通过合理地模拟风速和风电机组的出力情况,并采用时序蒙特卡罗模拟方法进行各类发电机组、输电设备的时序状态模拟;针对不同故障持续时间下单位负荷损失不尽相同的特点,充分考虑各类负荷的差异及故障持续时间,以系统发电成本和负荷损失费用之和最小为目标建立的优化调度模型更加符合电力市场环境下的实际情况。IEEE-RBTS测试系统的算例结果表明所建立的模型能够使负荷损失费用相对较小,而且风电机组对系统可靠性的贡献与其接入的风速区类型、容量、节点位置等具有密切关系,应当根据实际情况进行深入分析。     

含具有风速相关性风电场的发输电系统可靠性评估

提出了一种改进相关矩阵蒙特卡罗模拟法与拉丁超立方采样法相结合的多维相关风速抽样方法,并把该方法应用于含多个风电场的发输电系统可靠性评估。通过实际风速数据对模型的验证表明：提出的风速相关模型能够充分保持实际风速数据的概率分布,基本统计量和相关特性。将该模型和方法应用到 MRTS可靠性测试系统中,证明了该方法适用于含具有风速相关性的风电场的发输电系统可靠性评估。并通过算例,对风速相关性程度、风电场接入位置和风能渗透水平三个因素对含风电场的发输电系统可靠性的影响进行了分析。     

计及风机故障相关性的发输电组合系统可靠性评估

随着风电场规模的不断扩大,风电并网对系统可靠性的影响越来越明显。基于非序贯蒙特卡罗模拟法建立了含风电场的发输电系统可靠性评估模型,该模型考虑了风速的随机性和同一风电场内风电机组停运事件的相关性。建立了计及风电上网量的多目标优化切负荷模型,并应用于风电场接入后系统可靠性评估。以IEEE RTS-79系统为例验证了算法和模型的有效性,并分析了风电场接入后系统可靠性的影响因素。     

含风电场的发输电系统可靠性评估

基于序贯蒙特卡罗仿真方法,建立含风电场的发输电系统充裕度评估模型。计及输电线路故障和输电线路有功限制,建立考虑风向、尾流效应以及地形因素影响的风电场内各台机组捕获风速计算模型,并提出了新的关于风电场接入系统的可靠性指标。利用Matlab7编写了相应程序,对引入该模型的IEEE-RTS79系统进行可靠性评估。通过对比不同的接入方案,充分评估大规模风电场对发输电系统可靠性的影响。     

发输电组合系统可靠性评估的蒙特卡罗模拟

发输电组合系统是指包含发电机,变压器、母线段,断路器、继电保护装置,自动重合闸和输电线路构成的电力系统。文中讨论了系统故障模式判判断、各子系统数学模型及算法的实现问题,用算例子进行计算,验证了该方法的可行性及正确性。相应的应用软件已用于实际系统的可靠性评估。     

含VSC-HVDC的交直流混合发输电系统可靠性评估

建立了含柔性直流输电(voltage source converter based high voltage direct current,VSC-HVDC)的交直流混合发输电系统的可靠性分析模型,该模型既考虑了VSC-HVDC的稳态功率特性,还计及了发输电网络的故障率和输电线路的有功限制,采用非序惯蒙特卡罗仿真实现;在满足系统安全约束的前提条件下,对系统进行模拟调度,重点评价了与发输电网络连接的VSC-HVDC对电网可靠性的影响,给出系统和节点的风险指标,为VSC-HVDC规划和运行提供参考依据,最后算例分析证明了该算法的可行性和合理性。     

考虑风电场影响的发输电系统可靠性评估

风能具有随机波动性,相应的风力发电机出力具有不确定性.对含有风电场的发输电系统可靠性展开研究,在考虑风速的时序性和自相关性、风力发电机输出功率特性以及强迫停运影响的基础上,把风力发电机可靠性模型与输电网可靠性模型相结合,在满足电力系统安全性约束条件下,建立以电网最大负荷供应能力为目标的发输电系统可靠性评估模型,用于评估风电场并网后对输电网可靠性的影响,以IEEE-RTS79测试系统为算例,对反映风电场影响的相关可靠性指标进行分析计算,研究结果可为风电场接入电网方案的合理制定提供科学决策依据.     

考虑风电场影响的发输电系统可靠性评估

风能具有随机波动性,相应的风力发电机出力具有不确定性.对含有风电场的发输电系统可靠性展开研究,在考虑风速的时序性和自相关性、风力发电机输出功率特性以及强迫停运影响的基础上,把风力发电机可靠性模型与输电网可靠性模型相结合,在满足电力系统安全性约束条件下,建立以电网最大负荷供应能力为目标的发输电系统可靠性评估模型,用于评估...     

计及风电场的发输电系统风险评估

基于序贯蒙特卡罗仿真建立了计及风电场的发输电系统风险评估模型,该模型考虑了风速的随机性和风电机组的强迫停运,将风电场可靠性模型与发输电组合系统相结合.基于效用理论提出了风电场接入后系统的风险指标.采用Matlab编写了相应程序,以IEEE-RTS79系统为例验证了本文所提模型的有效性,并分析了风电场接入对发输电系统的影响.     

风电场对发输电系统可靠性影响的评估

建立了基于蒙特卡罗仿真的含风电场的发输电系统可靠性分析模型,该模型不仅考虑了风速的随机性、风电机组强迫停运率及其与气候的相关性,而且计及了输电网络故障率和输电线路有功功率限制.将该模型应用于含风电场的电力系统仿真,按照在满足系统安全约束条件的前提下充分利用风电的原则,对系统进行模拟调度,计算出能反映风电价值的可靠性指标,为风电场的规划与运行提供了重要的参考价值.     

Reliability assessment of bulk electric systems containing large wind farms

Wind power is an intermittent energy source that behaves quite differently than conventional energy sources. Bulk electric system reliability analysis associated with wind energy conversion systems (WECS) provides an opportunity to investigate the reliability benefits when large-scale wind power is injected at specified locations in a bulk electric system. Connecting the WECS to different locations in a bulk system can have different impacts on the overall system reliability depending on the system topology and conditions. Connecting a large-scale WECS to an area which has weak transmission could create system operating constraints and provide less system benefit than connecting it to an area with stronger transmission. This paper investigates bulk electric system transmission constraints associated with large-scale wind farms. The analyses presented in this paper can be used to determine the maximum WECS installed capacity that can be injected at specified locations in a bulk electric system, and assist system planners to create potential transmission reinforcement schemes to facilitate large-scale WECS additions to the bulk system. A sequential Monte Carlo simulation approach is used as this methodology can facilitate a time series modeling of wind speeds, and also provides accurate frequency and duration assessments. An auto-regressive moving average (ARMA) time series model is used to simulate hourly wind speeds.     

Reliability centered planning for distributed generation considering wind power volatility

This paper investigates a stochastic planning model to minimize the lifecycle cost of distributed generation (DG) systems under the energy reliability criterion, namely the loss-of-load probability. In particular, our study focuses on the DG system penetrated by renewable wind technology. The optimization is formulated to determine the wind turbine capacity and their placement in the DG system with the intent to minimize the capital, operational and environmental costs. Statistical moments including mean and variance are utilized to characterize the wind power volatility and the load uncertainty. Genetic algorithm combined with heuristic search is used to find the best sitting and sizing of the distributed energy recourses. Our study is among the first attempts in the literature to model and optimize DG system based on continuous probabilistic theory. The moment methods are shown to be effective in characterizing the stochastic behavior of wind power and load dynamics. Case studies are provided to demonstrate the application and performance of the planning method.     

发输电系统可靠性分析中最优切负荷模型

电力系统可靠性分析的过程中系统状态分析环节最为核心,也最为费时,尤其是在状态抽样中用到枚举法或者蒙特卡洛模拟法时,需要进行大量的系统状态分析。本文提出切负荷量最小兼顾负荷重要度和区域就近削减负荷原则来进行负荷削减。重要度原则体现在削减负荷时按负荷级别进行削减,区域就近原则使得切负荷点不再在全系统范围内搜寻,大大减少了计算时间。通过IEEE-RTS79可靠性测试系统的计算结果可知,该法在减少计算时间方面有明显的优势,切负荷量也更切合实际情况。     

Well-being analysis for composite generation and transmission systems

This paper presents a new approach to evaluating the health of composite generation and transmission systems. A well-being framework is used to classify the system states into healthy, marginal and at risk, according to a pre-defined deterministic criterion. In order to combine deterministic and probabilistic concepts, the proposed methodology uses a nonsequential Monte Carlo simulation, a multilevel nonaggregate Markov load model and new test functions to estimate the well-being indices. These test functions are based on an estimating process, designated as the one-step forward state transition, which is very flexible and efficient. Case studies on the IEEE-RTS (Reliability Test System) and on a modification of this system are presented and discussed.     

基于最小负荷削减费用的输电系统可靠性评估

电力系统可靠性的经济价值日益受到人们的重视。常规可靠性评估方法采用以负荷削减量最小为目标函数的最小负荷削减模型,由此得出的负荷削减量虽然最小,但负荷削减费用不是最小,忽视了经济价值。提出基于最小负荷削减费用的可靠性评估模型,以负荷削减费用最小为目标函数,并考虑节点负荷类型的分类,克服了常规方法忽视经济价值的缺点。所提出的方法较常规方法虽然负荷削减量大,但负荷削减费用小,符合从经济价值出发的原则。通过算例分析表明了该方法的合理性和实用性。     

Day-ahead allocation of operation reserve in composite power systems with large-scale centralized wind farms

This paper focuses on the day-ahead allocation of operation reserve considering wind power prediction error and network transmission constraints in a composite power system.A two-level model that solves the allocation problem is presented.The upper model allocates operation reserve among subsystems from the economic point of view.In the upper model,transmission constraints of tielines are formulated to represent limited reserve support from the neighboring system due to wind power fluctuation.The lower model evaluates the system on the reserve schedule from the reliability point of view.In the lower model,the reliability evaluation of composite power system is performed by using Monte Carlo simulation in a multi-area system.Wind power prediction errors and tieline constraints are incorporated.The reserve requirements in the upper model are iteratively adjusted by the resulting reliability indices from the lowermodel.Thus,the reserve allocation is gradually optimized until the system achieves the balance between reliability and economy.A modified two-area reliability test system （RTS） is analyzed to demonstrate the validity of the method.     

Modeling of wind farms in the load flow analysis

Two methods are proposed, for the simulation of wind farms with asynchronous generators in the load flow analysis. Both methods are based on the steady-state model of the induction machine. The first involves improving the conventional PQ bus, and the second involves modeling the generators in steady-state in the bus where the wind farm is located. The two sets of results are then compared     

风电场可靠性评估

建立了基于蒙特卡罗仿真的风电场可靠性模型，该摸型考虑了风速的随机性、风电机组强迫停运窄受天气状况的影响．并应用该模型对含风电场的发电系统进行仿真．计算出能反映风电价值的可靠性指标和经济指标，为风电场的规划与运行提供参考。     

发输电组合系统可靠性评估的Monte-Carlo仿真及并行处理

并行处理为大规模电力系统问题的分析和计算提供了新的机会和挑战，为大大缩短电力系统可靠性评估的计算时间，实现在线应用提供了强有力的支持：本文介绍了发输电组合系统可靠性评估的基本概念，并详细分析了各种Monte-Carlo仿真的基本原理，提出了一种基于粗颗粒异步算法的并行处理的网络拓扑结构，并分析其基本原理，最后介绍了实现主从处理器以TCP／IP方式通信的方法。