一次泵变流量系统变压差优化控制方法

摘要

建立基于末端压差控制的一次泵变流量水系统仿真模型,旁通回路采用最小流量控制法,冷冻水泵采用变转速与变台数混合控制调节流量.研究末端压差控制系统的运行特性,并提出变压差设定值优化控制策略,通过调整末端压差使得仅最大阀位支路二通阀全开,且能够保证用户流量需求.在用户侧30％～100％负荷率下,与定压差控制进行冷冻水泵功耗对比,结果表明:在60％负荷率时,节能率达到28.1％.%The simulation model of the variable primary flow system based on terminal differential pressure control is established.The minimum flow control method is applied to the bypass circuit,and the rotating speed and sequence control on the chilled water pump are adopted to adj ust the flow rate.The operating characteristics of the terminal differential pressure control is studied.The optimal control strategy with variable differen-tial pressure set-point is put forward,which is able to keep the two-port valve in the maxi-mum valve position branch at full opening degree and satisfy the flow needs for the users. The chilled water pump power consumption under 30％-100％ of load rate in the user side using this control strategy is compared with that using the constant differential pres-sure control strategy.The results show that the energy-saving rate is up to 28.1％ under 60％ of load rate.