【作者】 孙伟卿；

【导师】 张焰；

【作者基本信息】 上海交通大学 ， 电力系统及其自动化， 2013， 博士

【摘要】 智能电网是人类社会应对资源紧缺、环境污染等一系列问题而提出的现代化电力供应系统。与传统电网相比，智能电网对电网规划、运行和管理的各个环节提出了更高的要求，要求电能生产、输送和消费的整个过程更加高效、经济和安全，同时具备更好的可操控性，提供更佳的用户体验。在电力系统分析与计算中，通常以刚性约束的形式描述系统运行约束条件。一方面，这样的刚性描述方法过于刻板，很难满足智能电网对系统规划与运行管理灵活性的需求。另一方面，大量新技术的应用丰富了电力系统的控制手段，要求智能电网能够根据电网实际运行状态，灵活控制系统的各项运行参数。本文将工业过程系统设计中的柔性分析方法引入到电力系统分析与优化中，系统地提出智能电网规划与运行控制的柔性评价及分析方法。本文所做的研究工作主要包括以下几方面：1.在分析传统的电力系统优化模型中约束条件刚性表示方法不足的基础上，提出电力系统运行约束条件的柔性描述与分析方法；分析比较柔性分析方法与模糊集理论、概率理论，以及灰理论的区别；定义智能电网中的柔性概念，并对其进行分类描述；提出智能电网柔性评价的一维线性指标，并根据电网运行约束类型的不同，将该柔性评价指标从一维扩展至多维。2.基于对最优潮流模型中等式和不等式约束条件的柔性化描述，进一步提出电网运行优化目标函数的柔性化表示方法，并将其转化为柔性等式约束的形式；兼顾电网运行的经济性、安全性与可靠性，建立智能电网经济调度的多维柔性综合优化模型，并提出模型求解方法。3.将柔性分析方法应用于智能电网规划中，以柔性化方法评估整个电网规划周期内的投资成本、运行成本和可靠性收益；同时，通过对输电线路负载率约束的柔性化表示，在规划过程中保留部分系统输送能力，从而为系统预留一定的运行安全裕度和对不确定因素的适应能力。4.根据输电线路实时动态热整定（RT-DTLR）系统的监测数据，确定输电线路的实时热稳定极限；通过对线路潮流约束进行柔性化表示，实现对线路潮流的灵活控制；将该技术与传统的电力系统切负荷策略相结合，综合考虑系统风险与收益，提出考虑RT-DTLR技术的智能电网柔性切负荷策略，并以满意度评价方法进行求解。5.阐述智能电网中利用负荷柔性改善系统运行水平的实现方法；分析电动汽车作为智能电网中一类重要的柔性负荷，其充放电行为对电网运行的影响；研究智能电网对电动汽车充放电行为的引导与管理措施，分析电动汽车换电站的负荷柔性，通过对电动汽车换电站最优充放电策略的研究，求取电动汽车换电站的日负荷曲线，实现对其负荷的有序管理，并以此为依据分析换电站负荷对电网运行的影响。6.提出电力系统运行均匀性分析与评估方法，在电网结构确定的情况下，分析系统运行均匀性与经济性和安全性之间的关系；从电力系统运行状态和安全裕度两个角度，定义系统状态均匀度和固有均匀度评估指标；针对固有均匀度指标直接求解的困难，利用本文提出的柔性分析方法，提出基于设备负载率柔性约束参数δ U和δ L的优化模型并进行求解。本文以Garver6，IEEE14和IEEE30节点测试系统作为算例，分析和验证本文提出的智能电网规划与运行控制中柔性评价与分析方法的有效性。更多还原

【Abstract】 Smart grid is a modern electric energy supply system to deal with a series of problems,such as resource shortage, environment pollution, etc., in human society. Compared withconventional power grids, smart grid sets much higher requirements on power gird planning,operation and management. The whole process of electric energy generation, transmission andcomsuption is required to be more efficient, economical and secure. Meanwhile, smart gridalso provides better controllability and user experiences.In power system analysis and calculation, system operation constraints are usuallyexpressed in rigid forms. On one hand, such a rigid expression method appears to be tooinflexible to meet with the inquirements on flexibility of smart grid planning, operation andmanagement. On the other hand, with the large number of application of new technologies,control methods of power systems are greatly enriched. Smart grids are required to controlsystem operation parameters flexibly according to the actual grid operating states. Thisdissertation introduces flexibility analysis method in industry process system design to powersystem analysis and optimization, and systematacially proposes flexibility evaluation andanalysis method of smart grid planning and operation control.Main research works and innovative points of this dissertation are as follows:1. The disadvantages of rigid constraints in conventional power system analysis are firstanalyzed. Then, the concept of power system flexibility expression and analysis method isproposed and compared with fuzzy set theory, probability theory, and grey theory. After that,flexibility in smart grid analysis is defined and classified. A one-dimension linear index is proposed to evaluate smart grid flexibility. According to the different constraint types inpower system operation, it is then extended from one-dimension to multi-dimension.2. Based on the flexible expression of equality and inequality constraints in optimalpower flow models, the flexible expression method of grid operation objective function isproposed. And the objective function is transferred to a flexible equality constraint. Then,taking grid operation economy, security and reliability into account, a multi-dimensionflexible comprehensive optimization model for smart grid economic dispatch is establishedand solved.3. Flexibility analysis method is applied in smart grid planning. System investmentcosts, operation costs and reliability benefits are evaluated flexibly in the whole planningcycle. Meanwhile, through the flexible expression of transmission line load rate constraints,some system power flow transmission ability is reserved, so that a certain degree of systemoperation security margin and adaptability to uncertain factors can be reserved.4. Based on the monitoring data from real-time dynamic thermal line rating (RT-DTLR)system, the real-time thermal stability limits of lines can be determined. Through the flexibleexpression of transmission line power flow constraints, line power flow can be controlledflexibly. Then, RT-DTLR technology is combined with conventional power system loadshedding strategies. Taking both system risks and benefits into account, a smart grid flexibleload shedding strategy involving RT-DTLR technology is established, and it is solved usingsatisfaction evaluation method.5. The realization method of improving power system operation level by use of loadflexibility is first elaborated. Then, acting as an important kind of flexible load in smart grid,the effect of electric vehicle charging and discharging activities to power system operation isanalyzed. Based on the analysis of guidance and management measures of electric vehicles,the load characteristic of electric vehicle battery swapping station (EVBSS) can be obtained.After that, a model for optimal charging/discharging strategy of EVBSS is established and solved, so that the daily load curve of EVBSS can be obtained and the load of EVBSS can bemanaged orderly. Finally, base on the daily load curve obtained, the effect of EVBSS load onpower grid operation is analyzed.6. Power system operation homogeneity analysis and evaluation method is proposed,and the relationship among system economy, security and homogeneity is analyzed. For theconsiderations of system operation states and security margins, degrees of power system statehomogeneity and inherent homogeneity are defined respectively. For the difficulties in directsolution of inherent homogeneity index, the flexibility analysis method proposed in thisdissertation is used. An optimal model based on flexible device load rate constraintparametersδ Uandδ Lis established and solved, so that the inherent homogeneity indexcan be obtained.Garver6-bus, IEEE14-bus and IEEE30-bus test systems are used to analyze and verifythe validity of the flexibility evaluation and analysis method of smart grid planning andoperation control proposed in this dissertation.更多还原