分布式供能系统建模优化能流逻辑思维图详解

The Logic Modeling/Optimizing Energy Flux Chart of DES/CCHP

针对复杂分布式供能系统DES/CCHP建模优化中把不同子系统的目标函数形式上加合成为系统目标函数但因其相互间并不存在关联而无法求解的问题,给出了表述DES/CCHP与其各个子系统的能流关系的逻辑思维图,指出了DES/CCHP包括蒸汽动力、区域供冷、区域供暖、生活热水、可再生能源发电、工业余热利用、智能微电网、天然气微网及LNG物流、氢能等9个子系统,提出了采用分解协调优化的策略和方法;首先对拓扑结构、设备参数、各种变量之间有可描述关系的各子系统分别建模和优化求解;然后在各个子系统之间多次迭代协调优化,电力是最主要的协调变量;进而指出上图是物理模型和能流模型的集成,但也蕴含着多种功能层次模型;只有在多种运行/营销层次工况初步优化结果的基础上才能建立设计/决策层次模型,并反复迭代才能获得优化结果。强调优化的直接目标是经济性,最高能效目标来自基于科学用能原理所选择的子系统拓扑结构和参数,碳排放最少的目标则取决于能效和一次能源的构成。上述方法已用于多个天然气DES/CCHP工程的规划和建设,有重要的科学意义和实用前景。

For the dilemma of modeling optimizing of DES/CCHP due to the absents of variable-interrelation among sub-systems,a logic modeling/optimizing energy flux chart of DES/CCHP is advanced,which including 9 sub-systems,that are power-system,DCS,DWS,hot water,renewable generating,SMG,gas/LNG,hydrogen,and industrial waste heat. It was pointed out that the topology structure parameters inside a sub-systems are may be described and optimized,but not existed among different subsystems.Therefore,a Decomposing/Coordinating strategy has been adapted and electricity is the main coordinating variable. Two main strategies are advanced：（ 1） Modeling optimization was realized via optimizing and iterating among multi-operation-subsystem modeling with design modeling;（ 2） The direct targets of optimization was the economic benefit,high energy-efficiency target comes from sub-system decision according to the principle of＂Use energy scientifically＂,while low carbon target depends upon energy efficiency and choosing of primal energy. Above method has been applied in design construction of many natural gas DES/CCHP projects.Thus,it has important scientific meaning and practical prospect.