节点文献
基于耗散功率分量的无功服务定价
Var Supporting Pricing Based on Branch’s Dissipation Power Components
【作者】 文明;
【导师】 彭建春;
【作者基本信息】 湖南大学 , 电力系统及其自动化, 2010, 博士
【摘要】 无功服务定价是无功管理中一项根本的、必要的内容。建立合理的无功服务价格机制对传统电力工业的改革具有经济和指导意义,具体表现在:第一,明确的无功服务价格信号能引导用户合理的无功消费行为;第二,促进合理的无功电源分布,提高电力系统稳定性和可靠性;第三,改善用户电压质量;第四,提高系统运行的经济效率。目前无功服务定价方法主要有边际成本法和综合成本法两类。边际成本法将优化问题中无功平衡约束的影子价格作为该节点的无功服务电价。该方法能提供丰富的经济激励信息,但却不能实现无功服务成本的收支平衡,而且随着模型中目标函数和约束条件的不同,各节点的无功服务电价存在较大差异。综合成本法把无功服务定价的问题转变为单位无功服务成本如何分配的问题,该方法思路简洁、能确保收支平衡,但它忽略了不同无功电源对无功服务电价的影响,且不能向无功服务用户提供经济激励信息。在剖析边际成本法和综合成本法的优缺点后,本文提出基于耗散功率分量的无功服务定价方法。首先打破传统无功服务对象的概念,将需要无功服务支持的负荷有功和发电机有功及直接消耗无功功率的负荷无功一同视为使用无功服务的用户,将包括发电机无功、同步调相机在内的具有无功调节能力的电力设备视为提供无功服务的无功电源,然后基于电网的潮流解或状态估计解,将各无功电源输出的感/容性无功用等值并联电纳(简称“费用电纳”)替代,将各用户的功率用等值节点注入电流替代,从而建立无功服务定价的等值网络。最后运用耗散功率分量算法求各无功服务用户在费用电纳上产生的耗散无功分量及其对应的无功服务费用,总加所有费用电纳上某用户有功(无功)对应的无功服务费用,并求得单位无功服务费用,即为该用户的无功服务电价。在联营模式下,提出了一种基于依赖性和耗散功率分量的无功服务定价方法。首先利用电网无功损耗对用户消费电能的灵敏度来量化用户对无功服务依赖性,进而将无功服务费用分解成依赖费用和转归费用两部分。根据用户对电源无功的依赖度,按比例分摊无功服务的依赖费用,同时按基于耗散功率分量的无功服务定价方法分配转归费用部分,最后将两部分累加得到用户消费单位有功(无功)的无功服务费用,即为该用户的无功服务电价。在联营/双边模式下,提出了一种基于依赖性和耗散功率分量的无功服务定价。首先介绍了一种描述电力市场中联营和双边交易的通用交易向量,然后将无功服务设计成联营模式下的无功交易和双边模式下的有功交易。再探讨了联营/双边模式下各类交易对无功服务依赖度和耗散功率分量的算法。进而得到各交易承担的无功服务依赖费用和无功服务转归费用。最后,得到各交易单位有功(无功)的无功服务费用。对IEEE118节点等多个系统进行仿真计算,结果表明本文提出的无功服务定价方法具有以下特点:适用任意结构和有环流的电网,克服以往研究中无法考虑P-Q耦合影响的情况,能够适应多种交易模式,且能在确保收支平衡的前提下为各交易和无功服务用户提供有效的经济激励信号。
【Abstract】 Reactive power support pricing is a fundamental and consequential part of reactive power management. Establishing the pricing mechanisms of reactive power service is important for the deregulated power industry both financially and operationally as the following reasons. Firstly, as a correct price signals, it is an important guidance for consumers to decide their behavior. Secondly, it can promote reasonable planning of reactive power supplies in order to enhance the system stability and reliability. Thirdly, it can improve the voltage quality. Fourthly, it can enhance economic efficiency of system operation.Much research work has been done on reactive power pricing. All of them can be divided into two categories:reactive power pricing method based on marginal cost theory and reactive power pricing method based on aggregate cost theory. In marginal cost theory, shadow prices which are obtained from the reactive power equal constraints of the OPF problem is regarded as the nodal reactive power pricing. The reactive power price based on the marginal cost theory can provide abundant economic information. However, this theory could not achieve payment balance between the cost and income of reactive power support. Even worse, the reactive power price of each node is not steady because of the difference of objective function or constraint condition. The aggregate cost theory changed the reactive power pricing problem into reactive power allocation problem. This method is concise and also can guarantee payment balance. However, this method neglects that different reactive power has different influence to reactive power price. Economic information is also lacked in this method.Based on the above analysis to marginal cost theory and aggregate cost theory, a novel method for reactive power support pricing based on dissipation power components is presented in this paper. Firstly, the traditional concept of reactive power support customer is broken, the load active power, generator active power and load reactive power are defined as reactive power support customer, meanwhile, the generator reactive power, synchronous condenser and also other reactive equipment are defined as reactive power sources in this method. Then each of reactive power sources used for var support is modeled by a shunt susceptance called "cost susceptance"; each of reactive consumers is modeled by each of their equivalent nodal injection current sources based on power flow solution. Finally, both reactive power fractions and var support cost induced by reactive power consumers on cost susceptance are determined based on the algorithm of dissipation power components. The unit var supporting cost is calculated, which is var supporting price of reactive consumers.A novel method for reactive power support pricing based on dependence and dissipation power components is presented in the pool model. Firstly, the sensitivity between reactive power loss and used power is used to quantize the dependence factor. And then, the reactive power support payment is divided into dependence payment and imputation payment. The dependence payment is allocated in proportion to the dependence factor and the imputation payment is allocated based on dissipation power components. The reactive power support payment and price of each unit active/reactive power are obtained by combining these two parts.Furthermore, a novel method for reactive power support pricing based on dependence and dissipation power components is presented in the pool/bilateral model. First, a general tranction vector referred to pool tranction and bilateral tranction is depicted. And then, the reactive power support is constructed as the combination of reactive tranction in pool model and active power tranction in bilateral model. The algorithm of dependence factor and dissipation power components is discussed in pool/bilateral model. Then, the dependence payment and the imputation payment of each tranction are obtained. At last, the reactive power support payment and price of each tranction are obtained.The calculation results of IEEE118 system and other test systems show that the method presented in this paper has these below characteristics:it is applicable for any transmission systems of looped configurations and loop flows; it doesn’t need any assumption and simplification and takes account of the interaction between active and reactive power; it achieve payment balance between the cost and income of reactive power support and also has abundant economic information.
【Key words】 Power market; Reactive power ancillary service; Pricing; Dependence; Dissipation power component;