高校供热系统调控策略优化研究

Research on Optimizing Control Strategy of Heating System in Colleges and Universities

针对北方高校,以稳态传热模型为基础,开发包含热力站、二级管网、建筑在内的供热系统仿真模型。结合校园建筑分时段使用的特点,提出供热系统启停、建筑使用期间室温调控优化方法。采用仿真模型,对优化后的调控策略效果进行模拟分析。以稳态传热模型为基础,开发的供热系统仿真模型的仿真结果可信。调控策略1(3:00供热,22:00停热,在建筑使用期间8:00—22:00,二级管网流量固定,热力入口电动调节阀保持初始相对开度不变)下,严寒日(2020年1月8日8:00至1月9日8:00)、末寒日(2020年3月10日8:00至3月11日8:00)教学楼使用期间的室内温度均满足甚至高于18~20℃的要求。22:00停热后室内温度经过快速下降后变得缓慢,这主要得益于建筑热惰性。由于供热开始时间过早,建筑非使用期间室内温度偏高,1月9日8:00、3月11日8:00室内温度分别达到19.5、21.8℃,存在着较为严重的过量供热问题。与调控策略1相比,调控策略2(严寒日停热时间为21:00,供热时间为5:00。末寒日停热时间为19:00,供热时间为7:00。在建筑使用期间,二级管网流量固定,热力入口电动调节阀相对开度保持初始相对开度不变)进行了启停策略优化,进一步提前停热、延后供热,仍能满足建筑使用期间的室内温度要求,建筑非使用期间的室内温度也明显合理。建筑热惰性确保了停热后室内温度的有限下降,严寒日供热开始时,室内温度为16.6℃;末寒日供热开始时,室内温度为17.9℃。与调控策略2相比,调控策略3(启停优化策略+热力入口电动阀室温调控:严寒日停热时间为21:00,供热时间为5:00。末寒日停热时间为19:00,供热时间为7:00。在建筑使用期间,调节热力入口电动调节阀相对开度,使室内温度保持在18~20℃)可将建筑使用期间的室内温度控制在要求范围内。采取启停优化策略+热力入口电动阀室温调控,不仅使建筑使用期间的室内温度控制在要求范围内,还利用建筑热惰性确保停热后室内温度的有限下降,有利于降低供热能耗。

Aiming at northern colleges and universities,based on the steady-state heat transfer model,a simulation model of heating system including heating station,secondary network and building was developed.Combined with the characteristics of campus buildings in different periods of time,the optimization method of room temperature control during the start and stop of heating system and the use of buildings was proposed.The simulation model was used to simulate and analyze the effect of the optimized control strategy.Based on the steady-state heat transfer model,the simulation results of the developed heating system simulation model are credible.Under the control strategy 1(heating started at 3:00,heating stopped at 22:00,the flow of the secondary network was fixed,and the electric control valve at the consumer heat inlet kept initial opening unchanged during the use period of the building from 8:00 to 22:00),the indoor temperature of the teaching building met or even exceeded the requirement of 18 to 20℃during the use period of the building on the severe cold day(from 8:00 on January 8 to 8:00 on January 9,2020)and the last cold day(from 8:00 on March 10 to 8:00 on March 11,2020).After stopping the heating at 22:00,the indoor temperature decreased slowly after a rapid decrease,which was mainly due to the thermal inertia of the building.Due to too early start of heating,the indoor temperature during the non-use period of the building was relatively high.The indoor temperature reached 19.5 and 21.8℃at 8:00 on January 9 and 8:00 on March 11,respectively.There was a serious problem of excessive heating.Compared with the control strategy 1,the start-stop strategy of the control strategy 2(the heating time was 5:00,and the heating stop time was 21:00 on the severe cold day.The heating time was 7:00,and the heating stop time was 19:00 on the last cold day.The flow of the secondary network was fixed,and the electric control valve at the consumer heat inlet kept the initial opening unchanged during the use period of the building)was optimized,and the heating was stopped in advance and the heating was delayed,which could still meet the indoor temperature requirements during the use period of the building.The indoor temperature during the non-use period of the building was also obviously reasonable.The thermal inertia of the building ensured a limited drop in the indoor temperature after the heating was stopped.When the heating started on the severe cold day,the indoor temperature was 16.6℃;when the heating started on the last cold day,the indoor temperature was 17.9℃.Compared with the control strategy 2,the control strategy 3(start-stop optimization strategy and room temperature control of the electric control valve at the consumer heat inlet:The heating time was 5:00,and the heating stop time was 21:00 on the severe cold day.The heating time was 7:00,and the heating stop time was 19:00 on the last cold day.During the use period of the building,the opening of the electric control valve at the consumer heat inlet was adjusted to keep the indoor temperature at 18 to 20℃)could control the indoor temperature during the use period of the building within the required range.Adopting the start-stop optimization strategy and the room temperature control of the electric control valve at the consumer heat inlet not only keep the indoor temperature within the required range during the use period of the building,but also use the thermal inertia of the building to ensure a limited drop in the indoor temperature after the heating is stopped,which is beneficial to reduce heating energy consumption.