Study On Optimization Method Of Ventilation And Air Conditioning System Operation Plan In Public Area Of Metro Station

The energy consumption of the subway system is high,and the proportion of the ventilation and air conditioning system is relatively large.Studies have shown that its electricity consumption accounts for 30%-40% of the total electricity consumption.The energy saving potential of the ventilation and air conditioning system is huge.This paper conducts energy-saving research on the ventilation and air conditioning system in the air-conditioning season from the operational strategy,and proposes methods and models to optimize its operation plan,which provides reference for the actual operation management of subway stations.Firstly,the actual survey and investigation on some stations of Xi'an Metro Line 2show that the passengers have relatively low requirements for the comfort of the subway station.The dynamic analysis method based on the relative thermal index RWI can better reveal the thermal comfort inside the subway station.The method for calculating the hourly target control temperature of the subway station is proposed by using this method.Secondly,it analyzes the characteristics of the air conditioning system load of the subway station,introduces the passenger flow prediction model and the reasonable estimation method of the permeation air volume of the station screen door and the entrance and exit station,and proposes the prediction method of the hourly operation load of the air conditioning system of the metro station.Based on the proposed calculation method of the target control temperature of the subway station and the hourly operation load forecasting method of the air conditioning system,the calculation model of the operation adjustment parameters of the ventilation and air conditioningsystem of the subway station is established according to the specific air treatment process of the subway station.Using MATLAB programming,importing weather forecast data,historical passenger flow data,station structure parameters and operation information,the hourly control parameters of each station air conditioning system can be automatically calculated in the short term.It provides a theoretical basis for the optimization of the operation plan of the ventilation and air conditioning system of the subway station.Finally,combined with the current equipment configuration status and operation adjustment strategy,a reasonable optimization plan is proposed.Taking the operation of the Xi'an Metro Line 2 City Library Station on a typical meteorological day as an example,the energy consumption of the fan under the current plan is compared with the optimization plan obtained by the theoretical model.The results show that the optimized scheme has better energy-saving effect,and the air-conditioning unit and the return-discharge fan can save energy by about 120.12 kWh in a single operation day.The analysis of the energy consumption of various parts of the system shows that the chiller accounts for a large proportion of the total energy consumption of the system,and the fluctuation of the chiller in whole day is the largest,which has a large energy saving potential.