节点边际电价的优化原理

Optimization Principle of Locational Marginal Pricing

为了实现电力市场的优化运营,关键是要建立安全约束经济调度与节点边际定价机制。安全约束经济调度能综合考虑系统的经济性与安全性目标,它既保证了系统的优化运行,也保证了系统的供电可靠性；而节点边际电价是从空间和时间2个层面尽量精确地反映电力系统的运行成本的定价机制。文中首先介绍了安全约束经济调度与节点边际价格的求解模型,描述了节点边际定价市场的优化原理；接着给出了节点边际电价的直流潮流法求解原理,并举例进行说明；最后指出节点边际电价有许多违反常规认识的地方,但这并不说明节点边际价格有错,关键原因在于电力系统运行除了遵守经济法则之外,还必须符合可靠性要求。

To optimize the operation of power system, it is necessary to establish security constrained economic dispatch（SCED） and introduce locational marginal pricing （LMP） method. Economics and security are very important under electricity deregulation, SCED can integrate these two objectives effectively, it ensure the optimal and reliable operation of power system, and it also is the basis of most established power markets. Nodal price is a good solution of cross-subsidiary; it can reflect the actual electricity supply cost in space and time scale, and is implemented in more and more areas. This paper firstly illustrates the model of SCED and LMP, and how the LMP-based market could optimize the economic efficiency; then introduces the DCflow method of LMP model, and makes it clear by an example. Finally, the paper points out that nodal price is very hard to understand, and it is counter-institutive in many aspects. However, nodal price itself is a well-designed mechanism. Power system operation should meet both the economic and reliability requirements, and this is why nodal price can be imagined easily.