光热电站间接式双熔盐罐储能系统通用建模方法研究

Indirect Two Tank Molten Salt Storage System General Modelling Approach of CSP

为适应电网调峰需求,发挥光热电站机组最大能效,光热电站通常配置一套熔盐(MS)储能系统,采用导热油作为传热介质(HTF),通过换热装置(HTX)进行导热油与熔盐的能量交换。介绍了间接式熔盐储能的通用建模方法,解决系统设计时对发电负荷及能量转换适配问题。计算以换热装置和熔盐罐模型为基础,对储热、放热模式进行运行状态描述,应用对数平均温差法计算变工况下的储热容量,考虑换热损失、熔盐罐散热损失、压力损失计算方式,针对熔盐流量、熔盐焓值和温度进行迭代计算,使用系统模型的仿真运行,结果表明模型能很好进行设计应用。

In order to meet the peak load regulation requirements of the power grid and give full play to the maximum energy efficiency of the concentrated solar power(CSP)plant,the CSP plant is usually equipped with the molten salt(MS)energy storage system,which uses oil as the heat-transfer fluid(HTF),and exchanges energy between HTF and MS through heat exchanger(HTX).It introduces a general modeling method of indirect molten salt storage system to solve the system design problem of adaptation in power generation load and energy conversion.Based on the HTX and MS tank model,the calculation modeling describes the operation state of the charging and discharging modes.The logarithmic mean temperature difference(LMTD)method is applied in calculation of the thermal capacity under variable operating conditions.Considering the calculation methods of HTX heat loss,molten salt tank heat loss and pressure loss,the iterative calculation is carried out for MS mass flow,MS enthalpy and temperature,then carry out the simulation operation of the system model.The results show that the model can be well applied in design.