中文摘要：

蓄能对分布式能源系统的效率有较大影响。本文对于分布式能源系统中蓄能的相变温度，分别采用熵产极值，煅耗散极值与广义热阻极值进行优化。结果表明，煨耗散极值与广义热阻极值作为优化准则所得的最优相变温度对应蓄热取热功率的极大值。此外，基于煅耗散分析方法，分析了二级蓄能的蓄热取热能力，结果表明二级蓄能的蓄热取热量比单级蓄能大，二级蓄能与单级蓄能蓄热量之比与冷热流体入口温度无关，仅与传热单元数有关，且当传热单元数趋于无穷大时，二级蓄能与单级蓄能的蓄热量之比趋于四分之三。

英文摘要：

For the phase change temperature of energy storage in distributed energy system, the entropy generation extremum, entransy dissipation extremum and general thermal resistance extremum are used to optimize the system. The results show that, when using the entransy dissipation extremum and the general thermal resistance extremum as optimization criteria, the optimal phase change temperatures correspond to the maximum thermal energy charge and discharge power. Based on the entransy dissipation analysis method, the two-stage energy storage unit is analysed in this paper, the results show that the thermal energy charge and discharge power of the two-stage energy storage unit is better than single stage energy storage, the ratio of heat storage increase only relates to the Number of Transfer Unit, when the Number of Transfer Unit verge to infinite, the ratio verge to 4/3.