基于机会约束规划的能源集线器系统气电购置优化建模

Optimal Gas-Electricity Purchase Model for Energy Hub System Based on Chance-Constrained Programming

随着能源集线器概念和多能协同互补思想的提出,由能源集线器之间的耦合与联接构成的能源集线器系统,对于共享、互补、经济、高效的能源传输和利用至关重要。由于气电购置量直接关系到系统的经济高效运行,其值可由系统与主网之间天然气管道和电力联络线上流过的能量来量化,但对于二者的常规约束过于保守,通过机会约束规划可以使约束具有一定的弹性,且在置信水平高于特定的置信水平时可在一定程度上保证系统的安全可靠性。基于此,在计及能源集线器内可再生能源不确定性出力下,将传统主要应用于对电力联络线交互功率的机会约束限制,延伸到对天然气管道传输功率的机会约束限制。该约束克服了常规约束保守性的问题,可调节系统气、电资源的合理分配。同时,建立电负荷需求响应模型,考虑能源集线器内各设备出力约束,以气电购置费用最小为目标,并在一定调度周期内将机会约束规划问题转化为确定性问题进行优化求解。优化结果证明对天然气管道和电力联络线上的气、电交互传输量进行机会约束限制会对能源集线器系统向主网的气电购置费用产生影响,并且重点讨论了分别对电力联络线交互功率和天然气管道传输功率实施机会约束限制以及不同置信水平参数设置对气电购置结果的影响。

With the concept of energy hub and the idea of multi-energy cooperation complementary, the energy hub system consisting of coupling and interconnection between energy hub is very important for building a shared, complementary, economic and efficient energy system. Because gas-electricity purchase is directly related to economic and efficient operation of the system, its value can be quantified through energy, but conventional constraints is too conservative for these two quantities. With chance-constrained programming, the constraints can be made with certain elasticity, and the confidence level above a specific value can guarantee safety and reliability of the system to a certain extent. This paper proposes an energy hub in renewable energy output uncertainty considerations, and traditional chance-constraint planning is applied to restrict power interaction between power system and external power grid and extended to natural gas flow between the energy hub system and external natural gas pipeline. This constraint overcomes the problem of conservatism of conventional constraints, and can adjust rational allocation of electrical and gas resources in interconnected system. Meanwhile, building load demand response model, and considering the output constraint of energy conversion device in the energy hub, aiming at minimum cost of gas-electricity purchase, in a certain scheduling period, the chance-constrained programming problem is transformed into a deterministic problem so as to facilitate optimization of the model. The optimization results show that electricity and gas transmission capacity of the powerlines and gas pipelines on chance constraints will affect purchase cost of gas-electricity to external system, and the gas-electricity purchase influence of chance constraint and different confidence level on interaction power and transmission flow is discussed respectively.