严寒地区办公建筑土壤源热泵系统运行策略优化研究

Study on the Operation Strategy Optimization of Ground-coupled Heat Pump System in Office Buildings in Severe Cold Region

严寒地区仅以供热为主的建筑在长期的连续运行或冷热负荷不平衡的条件下,对土壤源热泵(GCHP)机组的运行特性会产生负面的影响。通过改变和调节不同的运行策略,系统的运行特性会有较为明显的改善。本文以某办公建筑的土壤源热泵系统为研究对象,通过对系统连续2 a供暖季的长期监测,采集系统的运行数据,利用采暖度日数对室外温度进行修正,分析实例建筑中土壤源热泵系统的水温特性、能效指标、室内供暖效果等因素,对比土壤源热泵系统在不同运行策略下的运行特性,探究系统不同年份不同运行策略的优劣,使其高效节能;并利用熵权法和遗传算法,计算影响系统运行特性因素的指标权重,从而寻求土壤源热泵系统最优的运行策略。结果表明,通过实测得出采用单台机组以不同负载率运行时,热泵机组COP平均提高1.15,系统EER平均提高0.46,主机耗电量降低8.3%,系统耗电量降低10.8%,节能效果均提升20%左右;遗传算法求解最优运行策略各参数值,3月运行效果最优,地源侧循环水流量为21.99 m^(3)/h,用户侧循环水流量为79m^(3)/h,地源侧进水温度为5.78℃,用户侧出水温度为34.49℃。

In severe cold areas,buildings that only rely on heat supply will have a negative impact on the operation characteristics of ground-coupled heat pump (GCHP) units under the condition of long-term continuous operation or unbalanced cold and heat load. By changing and adjusting different operating strategies, the operating characteristics of the system will be improved significantly. In this paper,the GCHP system of an office building is taken as the research object. Through the long-term monitoring of the system for two consecutive heating seasons,the operation data of the system was collected. The outdoor temperature data was modified using heating degree days to analyze the water temperature characteristic,energy efficiency index,indoor heating effect and other factors of the GCHP system in the example building. By comparing the operation characteristics of the GCHP system under different operation strategies,the advantages and disadvantages of different operation strategies of the system in different years were explored to make it efficient and energy-saving. The entropy weight method and genetic algorithm were used to calculate the index weights of the factors that affect the operation characteristics of the system,so as to seek the optimal operation strategy for the GCHP system. The results show that when a single unit was operated with different load rates,the COP of the heat pump unit increased by 1. 15 on average,the system EER increased by 0. 46 on average,the power consumption of the host unit decreased by 8. 3%,the power consumption of the system decreased by 10. 8%,and the energy-saving effect increased by about 20%. Genetic algorithm was used to solve the parameters of the optimal operation strategy. The performance reached its peak in March,with the circulating water flow at the ground source side of 21. 99 m^(3)/h,the circulating water flow at the user side of 79 m^(3)/h,the inlet water temperature at the ground source side of 5. 78 ℃,and the outlet water temperature at the user side of 34. 49 ℃.