乏汽吸收式热泵动态特性实验研究

Experimental Study on Dynamic Behavior of the Exhausted Steam Absorption Heat Pump

采用吸收式热泵利用汽轮机乏汽余热供暖已逐渐成为火电厂的主要节能措施之一,但由于机组负荷变化频繁,使热泵经常偏离设计工况,运行效率低,供热性能差。为对热泵实施优化调节和控制,提高热泵运行效率,实验研究了热泵动态特性,结果显示,在驱动热源流量、低温水流量和低温水入口温度阶跃降低10%的情况下,在400s内,热泵制热量分别减少了18kW、2.1kW和14kW,冷却水出口温度分别降低了4℃、0.35℃和2.5℃,并通过仿真获得了动态响应过程的传递函数,为热泵优化控制提供了技术支持。

Using absorption heat pump which uses steam turbine exhaust steam waste heat for heating has gradually become one of the main technical measures of energy saving in power plant. The absorption heat pump systems often deviate from the design conditions because of the variation of operating parameters caused by frequently changes of unit load. So the efficiency of heat pump is low and the heating capacity cannot be guaranteed. The dynamic behavior of heat pump is researched using experimental methods so as to optimal regulate and controls of the heat pump and improve the unit efficiency. Results show that in the case of driving steam flow, chilled water flow and chilled water inlet temperature step changes down 10%, In 400 seconds, the heating capacity reduces about 18kW,2. 1kW and 14kW respectively, the cooling water outlet temperature reduces about 4℃, 0.35℃ and 2.5℃ respectively. Furthermore, a transfer function matrix is presented based on step simulation, providing technical support for the lithium bromide absorption heat pump optimization control.