【作者】 王俊；

【导师】 蔡兴国；

【作者基本信息】 哈尔滨工业大学 ， 电力系统及其自动化， 2013， 博士

【摘要】 电力系统区域间的可用输电能力(Available Transfer Capability, ATC)能够对发电和用电水平产生直接影响，在电力系统运行、规划等方面一直是倍受关注的重要指标，在保证系统安全可靠运行、避免输电阻塞、有效引导电力市场交易决策等方面具有重要意义。为了充分利用输电网络资源、提高系统安全性和可靠性，必须认识风电的随机特性和不确定性，深入分析风电对输电能力的影响，研究不同接入方式下电力系统区域间ATC计算和评估方法。风电场或风电机组所在位置的风速之间具有一定程度的相关性，现有风速模拟方法存在相关性描述不准确且效率低、稳定性差的问题。鉴于此，采取将非参数统计中的秩相关系数、Copula理论和传统蒙特卡洛仿真相结合的办法来处理不同位置风速间的相关性问题，同时在抽样过程中又引入了基于分层抽样的拉丁超立方技巧，进而建立了效率高、稳定性好且能考虑风速相关性的风速模拟方法，为本文后续内容奠定了研究基础。风电的接入增加了电力系统的不确定性，同时也带来了稳定性问题，所以，为了提高ATC评估结果的可信度，必须同时考虑系统的不确定性和稳定性问题。鉴于此，基于提出的风速模拟方法，将快速电压稳定指标纳入到ATC计算模型中，建立了电压稳定约束下考虑风电场间风速相关性的电力系统ATC概率评估方法。算例分析中通过计算潮流雅可比矩阵最小模特征值来检验系统是否能够保持电压稳定，研究了风速相关性对ATC的影响，分析了不同的风速相关系数与ATC样本值及其平均值、方差等的关系。研究成果可为系统运行人员制定功率传输计划提供理论支持。利用提出的风速模拟方法和ATC概率评估方法，以考虑发电区域内常规发电机组容量是否充足为研究基点，从风电功率可能导致线路阻塞进而限制输电能力的角度研究了处于不同区域、节点的风电场输出功率对系统区域间输电能力的影响。从风电具有间歇性和随机性特点的角度，通过引入风险度概念研究了风电不确定性、渗透率与系统区域间输电能力的关系。在此基础上，以最大化电力企业的效益为目的，通过关于输电能力的风险、效益模型，给出了一种风电集中式接入的电力系统最优输电能力评估方法，研究成果可为含集中式接入风电的电力系统规划和运行提供理论支持。在含有分散式接入风电的有源配电网中可能存在数量庞大的风电机组，受到数据短缺和计算复杂等原因影响，将无法得到风电机组所在位置的风速间的相关系数矩阵。针对此问题，通过建立极限相关结构法和相关变量集合法处理ATC评估中输入随机变量间相互依赖关系问题。在含大量分散式风电的电力系统区域间ATC评估中，利用该方法能够给出输入变量所有依赖结构下的ATC概率信息，降低了风电不确定性对评估结果可信度的影响，对随机变量间依赖关系不确定条件下的电能交易、系统运行调度具有重要的指导意义。更多还原

【Abstract】 Available transfer capability (ATC) between areas in power system can directlyaffects the power generation and electricity consumption level, is always animportant indicator to be concerned in running and planning of power system. ATChas an important significance in maintaining system security, avoiding thetransmission congestion and effective guiding the transaction decision-making forpower market. To take full advantage of the resources of power transmission grid,improve system security and reliability, we must realize randomness and uncertaintyof wind power generation and further analyse its influence on transfer capability,study calculation and evaluation methods of ATC under different grid-connectedpattern of wind power generation.There was a certain degree of correlation between wind speeds which werelocated at wind farms or wind turbines. Existing wind speeds simulation methodswere inaccurate and low efficient, poor stability in the aspect of correlation degreedescription. In view of this, it was proposed that a combination approach of rankcorrelation coefficient in nonparametric statistics, Copula theory and traditionalMonte Carlo simulation to deal with correlation of wind speeds between differentlocations, at the same time Latin Hypercube skills based on stratified sampling wereadded into the sampling process, then a good stability, high efficiency wind speedssimulation method was put forward which can consider the wind speeds correlation,above conclusions laid a research basis for the follow-up contents of this paper.Because grid-connected wind power generation increased the uncertainty ofpower system, meanwhile brought stability problems, we must syntheticallyconsider the uncertainty and stability of the system in order to enhance thecredibility of ATC evaluation results. In view of this, based on proposed windspeeds simulation method, this paper brought fast voltage stability indices intocomputation model of ATC, and proposed ATC probability evaluation method withconstraints of voltage stability considering wind speeds correlation between windfarms. In the example analysis, this paper calculated minimum module eigenvaluefor power flow Jacobian matrix to test whether the system was able to keep voltagestability and studied the influence of wind speeds correlation on ATC, which revealsrelationship between different correlation coefficient of wind speeds and ATCsample values, mean, variance, respectively. The research results can providetheoretical support for the system operator to make the power transfer plan.This paper took considering capacity of conventional power generator sets in power source area whether was adequate as research basic point, from perspective ofwind power which might cause line blocking and thus limit the transfer capability,and made use of proposed wind speeds simulation method and ATC probabilityevaluation method to study the effect of the output power from wind farms in thedifferent areas or nodes on transfer capability. From the perspective of intermittentand randomness characteristic of wind power, the paper researched relationshipbetween uncertainty of wind power, penetration level and transfer capabilitybetween areas by introducing concept of risk degree. On this basis, in order tomaximize the benefit of the power enterprise, the optimal evaluation methods oftransfer capability consider centralized grid-connected wind generation was given.The distribution power grid with wind power generation may have a largenumbers of wind turbines, affected by the shortage of data and computationalcomplexity, we would not be able to get correlation coefficient matrix between windspeeds for location of the wind turbines. Aimed to above problem, this paper builtlimit related structures method and correlation variables sets method to deal with theproblem of the interdependent relationship between the input random variables inthe ATC evaluation. In ATC evaluation with large amounts of distributed windpower generation between areas of power system, the method could give ATCprobability information under all dependent structures of the input variables,reduced the uncertainty of wind power generation impact on the credibility ofevaluation results and it has important guiding significance to electric power trading,system operation and dispatching under uncertainty condition of dependentrelationship between the random variables.更多还原