An energy-saving method for improving the air-conditioning operation parameters of a subway station according to meteorological data

Abstract

An energy-saving method for improving the operating parameters of the air conditioner in a subway station according to meteorological data. Collect initial basic data information, draw an enthalpy-humidity diagram for the interval enclosed by the tA air-conditioning return air temperature line, the hC mixed air enthalpy value line, and the hA air-conditioning return air enthalpy value. The enthalpy-humidity diagram gives the range of each working condition, including the small fresh air condition, the fresh air condition, the energy-saving condition, the low temperature energy-saving condition, and the ventilation condition. The temperature and humidity detector detects the outdoor temperature and humidity, calculates the enthalpy value and feeds it back to the indoor control system. The indoor control system selects the working condition according to the actual parameters, opens and closes the corresponding valves. The requirements for opening and closing the corresponding valves are to increase the fresh air volume and make the best use of the fresh air to handle the indoor cooling load. The remaining cooling load is handled by the subway central air-conditioning system. The corresponding fresh air valve is an adjustable valve, and its opening degree is adjusted according to the indoor and outdoor enthalpy values. The corresponding central air-conditioning system can be frequency-controlled and frequency-controlled according to the remaining indoor cooling load. The present invention improves energy efficiency and enhances the thermal comfort of passengers.

Description

Technical Field

[0001] The present invention belongs to the field of subway operation and relates to a control method for the operation parameters of the air conditioner in a subway station. Background Art

[0002] The construction period of the subway is tight. When designing the existing ventilation and air conditioning system, a consistent approach is usually adopted without accurately calculating its energy consumption according to climatic conditions. In addition, when designing the subway air conditioner, it is calculated according to the maximum load and a 10% design margin is considered. Therefore, during operation, it often cannot reach the full-load operation of the design condition, that is, it cannot operate at the optimal operating point, resulting in high energy consumption of the subway ventilation and air conditioning system. For the climate in spring and summer and rainy days in summer and autumn, due to improper adjustment of the working conditions, there is often a situation where the outdoor temperature is low while the temperature inside the subway station is high.

[0003] The existing "Code for Design of Subways GB 50157-2013" Article 13.2.14 stipulates that for the calculated indoor air temperature and relative humidity in the public area of underground stations in summer, when the station adopts an air conditioning system, the following regulations shall be met: the calculated air temperature in the public area of the concourse shall be 2°C to 3°C lower than the calculated dry-bulb temperature of the outdoor air for air conditioning and shall not exceed 30°C. The calculated air temperature in the public area of the platform shall be 1°C to 2°C lower than the calculated air temperature of the concourse, and the relative humidity shall be 40% to 70% in both cases. The relative humidity range is relatively wide, and the change range of the moisture content of the air corresponding to this relative humidity and temperature range is large. Therefore, there will be a situation where people feel stuffy on rainy days. Summary of the Invention

[0004] In order to overcome the deficiencies of the poor energy-saving performance and poor thermal comfort of passengers in the existing subway station air conditioning operation, the present invention provides an energy-saving method for improving the energy-saving performance and enhancing the thermal comfort of passengers by improving the operation parameters of the subway station air conditioner according to meteorological data.

[0005] The technical solution adopted by the present invention to solve its technical problems is:

[0006] An energy-saving method for improving the operation parameters of the subway station air conditioner according to meteorological data, comprising the following steps:

[0007] Step 1. Collect initial basic data information, and the process is as follows:

[0008] 1) Regional climate parameters given by the specification;

[0009] 2) Collect the predicted long-term evening peak passenger flow parameters of the subway station;

[0010] 3) Heat dissipation parameters of the platform screen door;

[0011] 4) Typical meteorological year parameters of the corresponding region;

[0012] Step 2. Calculate the number of people in the concourse, the number of people on the platform, and the heat dissipation and heat transfer of the platform screen door system;

[0013] Step 3. Calculate the heat generated by passengers, lighting, light boxes, signs, elevators, vending machines, security inspection systems, and ticket gates in the station's large system, the heat infiltration at each entrance and exit, stairway, and the convective heat transfer during parking time;

[0014] Calculate the moisture production of passengers, side walls, roof, and floor in the station, the moisture load at each entrance and exit, stairway, and the convective moisture load of the platform screen door;

[0015] Calculate the air-conditioning parameters and determine the air-conditioning operating parameters;

[0016] Step 4. Draw an enthalpy-humidity diagram for the interval enclosed by the tA air-conditioning return air temperature line, hC mixed air enthalpy value line, and hA air-conditioning return air enthalpy value. Give the range of each operating condition interval from the enthalpy-humidity diagram. The operating conditions include the small fresh air condition, the fresh air condition, the energy-saving condition, the low-temperature energy-saving condition, and the ventilation condition;

[0017] Step 5. The temperature and humidity detector detects the outdoor temperature and humidity, calculates the enthalpy value, and feeds it back to the indoor control system;

[0018] Step 6. The indoor control system selects the operating condition according to the actual parameters and opens and closes the corresponding valves. The opening and closing requirements of the corresponding valves are to increase the fresh air volume, make the best use of the fresh air to handle the indoor cooling load, and the remaining cooling load is handled by the subway central air-conditioning system. The corresponding fresh air valve is an adjustable valve, and its opening is adjusted according to the indoor and outdoor enthalpy values. The corresponding central air-conditioning system can be frequency-controlled and is frequency-controlled according to the remaining indoor cooling load.

[0019] Furthermore, in Step 4, the condition for the small fresh air condition is: outdoor air enthalpy value (hW) > enthalpy value at the middle of the platform public area (hA); the energy-saving condition is included in this condition. When the conditions are met: outdoor air enthalpy value (hW) > enthalpy value at the middle of the platform public area (hA), and the highest CO2 concentration in the public area < 600 ppm (i.e., 0.6‰, which can be manually set), it switches from the small fresh air condition to the energy-saving condition; when the conditions are met: outdoor air enthalpy value (hW) > enthalpy value at the middle of the platform public area (hA), and the highest CO2 concentration in the public area > 1200 ppm (i.e., 1.2‰, which can be manually set), it switches from the energy-saving condition to the small fresh air condition;

[0020] The condition for the energy-saving condition is:

[0021] The condition for the fresh air condition is: outdoor air enthalpy value (hW) ≤ enthalpy value at the middle of the platform public area (hA), and outdoor temperature (tW) ≥ air-conditioning supply air temperature (tO);

[0022] The condition for the low-temperature energy-saving condition is: air-conditioning return air enthalpy value hA < outdoor air enthalpy value h W≤The designed mixed air enthalpy value hC, and the outdoor temperature (tW) < the temperature in the middle of the platform public area (tA).

[0023] The condition for the ventilation mode is: the outdoor air temperature (tW) < (tO).

[0024] Furthermore, in step 6, when the outdoor air temperature is in the low-temperature energy-saving mode IV interval, the fresh air volume is opened to the maximum. Since the total supply air volume remains unchanged, the low-temperature mixed air enthalpy value hC' < the mixed air enthalpy value hC. Therefore, the low-temperature air-conditioning refrigeration capacity (hC' low-temperature mixed air enthalpy value * total supply air volume) < the air-conditioning refrigeration capacity (hC' mixed air enthalpy value * total supply air volume).

[0025] Preferably, in step 6, the opening and closing states of the valves are as shown in Table 1:

[0026]

[0027]

[0028] Table 1

[0029] Some of the opening degrees in the above Table 1 are determined through calculation.

[0030] The technical concept of the present invention is: according to the summer climate conditions in different regions, by increasing the fresh air volume, an air-conditioning operation strategy under specific regional conditions is given, which is of great significance for the energy conservation of public buildings such as subway stations that exist widely. Moreover, by introducing fresh air, the carbon dioxide concentration in the station can be further reduced, the oxygen content in the air can be increased, and while reducing the temperature in the public area of the subway station, not only the air quality is improved, but also the thermal comfort of passengers is increased.

[0031] The beneficial effects of the present invention are mainly manifested in: good energy conservation performance, increased thermal comfort of passengers, and improved air quality. Description of the Drawings

[0032] Figure 1 It is a specific method flow chart.

[0033] Figure 2 It is an example of the working condition interval corresponding to the enthalpy-humidity diagram.

[0034] Figure 3 It is the overall air-conditioning system diagram. Specific Embodiments

[0035] The present invention will be further described below with reference to the drawings.

[0036] Refer to Figures 1 to 3 , an energy-saving method for improving the air-conditioning operation parameters of a subway station according to meteorological data, comprising the following steps:

[0037] Step 1. Collect initial basic data information, the process is as follows:

[0038] 1) Query the regional climate parameters given in the specifications;

[0039] 2) Collect the predicted long-term late peak passenger flow parameters of the subway station;

[0040] 3) The heat dissipation parameters of the platform screen door;

[0041] 4) The typical meteorological year parameters of the corresponding region;

[0042] Determine the platform state point N, the concourse state point M, the outdoor state point W, the air supply point O, the outlet point L of the surface cooler, and the return air point A, and query the dry bulb temperature, relative humidity, moisture content, and enthalpy value of each;

[0043] Step 2. Calculate the number of concourse personnel, the number of platform personnel, and the heat dissipation and heat transfer of the platform screen door system, the process is as follows:

[0044] 1) Passenger flow calculation:

[0045] According to the passenger stay time in the station and the station passenger flow situation, calculate the number of personnel for the ventilation and air conditioning calculation of the concourse and platform through the following formula, and the passenger flow is calculated according to the predicted passenger flow of the long-term late peak.

[0046] Gc = (a1×a1 + b1×a2) / 60; Gp = (a2×a1 + b2×a2) / 60;

[0047] Where Gc—the calculated number of concourse personnel; Gp: the calculated number of platform personnel;

[0048] a1: The hourly boarding passenger flow of the station (persons / hour); a2: The hourly alighting passenger flow of the station (persons / hour);

[0049] a2: The platform stay time of boarding passengers (min); a1: The concourse stay time of boarding passengers (min);

[0050] b2: The platform stay time of alighting passengers (min); b1: The concourse stay time of alighting passengers (min);

[0051] The average stay time of passengers in the station is as follows (taking a two-story station as an example): The average stay time of boarding passengers in the station is the train operation interval plus 2 minutes, of which the concourse stay is 2 minutes and the platform stay is one train operation interval; the average stay time of alighting passengers in the station is 3 minutes, with 1.5 minutes of stay in the concourse and platform respectively;

[0052] 2) The platform screen door calculation is as follows:

[0053] Q = Q1 + Q2; Q1 = λ×S×ΔT;

[0054] Among them, Q—the heat dissipation and heat transfer amount of the platform screen door system (w);

[0055] Q1: The heat transfer amount of the platform screen door system (w); Q2: The heat dissipation amount of the platform screen door system (11×103 w);

[0056] λ: The heat transfer coefficient of the platform screen door, considered as a double-layer metal window (3 w / (m2·°C));

[0057] S: The area of the platform screen door (m2); ΔT: The temperature difference between the platform and the tunnel space (°C);

[0058] Step 3. Calculate the heat generated by passengers, lighting, light boxes, signs, elevators, vending machines, security inspection systems, and ticket gates in the large system of the station, the heat penetration at each entrance and exit, staircase opening, and the convective heat transfer during the parking time;

[0059] Calculate the moisture generation amounts of passengers, side walls, roof, and floor in the station, the moisture loads at each entrance and exit, staircase opening, and the convective moisture load of the platform screen door;

[0060] Calculate the air-conditioning parameters and determine the air-conditioning operating condition parameters.

[0061] This embodiment only focuses on the load calculation of the large system.

[0062] 1) Calculate the heat generation amount in the public area according to the number of passengers, lighting, light boxes, signs, elevators, vending machines, security inspection systems, and ticket gates in the large system multiplied by their respective heat dissipation amounts, the heat penetration of the ticket office, entrances and exits, heat transfer at staircase openings, heat dissipation and heat transfer of the platform screen door system, convective heat transfer during the parking time, and heat dissipation of the shops;

[0063] 2) Calculate the moisture generation amount in the public area according to the number of passengers multiplied by their respective moisture loads, the moisture loads of the station side walls, roof, and floor, moisture loads at entrances and exits, staircase openings, and the convective moisture load of the platform screen door;

[0064] The heat and moisture ratio of the platform = The total heat of the platform / The moisture generation amount of the platform;

[0065] The heat and moisture ratio of the concourse = The total heat of the concourse / The moisture generation amount of the concourse;

[0066] The calculated supply air volume of the platform = The total heat of the platform / (The return air enthalpy of the platform - The supply air enthalpy of the platform) * amplification factor;

[0067] The calculated supply air volume of the concourse = The total heat of the concourse / (The return air enthalpy of the concourse - The supply air enthalpy of the concourse) * amplification factor;

[0068] The fresh air volume of the platform = 0.15 * The calculated supply air volume of the platform;

[0069] The fresh air volume of the concourse = 0.15 * The calculated supply air volume of the concourse;

[0070] The fresh air volume per person on the platform = The minimum fresh air volume per person on the platform * The number of people on the platform;

[0071] Fresh air volume for concourse personnel = Minimum fresh air volume per concourse person * Number of concourse people;

[0072] Fresh air volume for air conditioning = max(Platform fresh air volume, Fresh air volume for platform personnel) + max(Concourse fresh air volume, Fresh air volume for concourse personnel);

[0073] Return air volume = Calculated supply air volume for platform + Calculated supply air volume for concourse - Fresh air volume for air conditioning;

[0074] Enthalpy value of mixed air hC = 0.85 * Enthalpy value of air-conditioning return air hA + 0.15 * Enthalpy value of outdoor air hW;

[0075] New air load for platform = max(Platform fresh air volume, Fresh air volume for platform personnel) * (hW - hA) * Magnification factor;

[0076] New air load for concourse = max(Concourse fresh air volume, Fresh air volume for concourse personnel) * (hW - hA) * Magnification factor;

[0077] Total supply air volume for the station = Calculated supply air volume for platform + Calculated supply air volume for concourse;

[0078] Cooling load of the large system of the station = Total supply air volume for the station * (hC - hO) * Magnification factor;

[0079] Step 4. In the interval enclosed by the tA air-conditioning return temperature line, the hC mixed air enthalpy value line, and the hA air-conditioning return enthalpy value, draw an enthalpy-humidity diagram based on the above parameters, and give the range of each working condition interval by the enthalpy-humidity diagram. The working conditions include the small fresh air condition, the all-fresh air condition, the energy-saving condition, the low-temperature energy-saving condition IV, and the ventilation condition.

[0080] When the outdoor air temperature is in the low-temperature energy-saving condition IV interval, open to the maximum fresh air volume. Since the total supply air volume remains unchanged and hC' low-temperature mixed air enthalpy value < hC mixed air enthalpy value, the low-temperature air-conditioning cooling capacity (hC' low-temperature mixed air enthalpy value * Total supply air volume) < Air-conditioning cooling capacity (hC mixed air enthalpy value * Total supply air volume);

[0081] According to the parameters of the typical meteorological year, give the meteorological parameters and the expected date interval for the expected start of the low-temperature energy-saving condition in the transition season, and give the corresponding theoretical energy consumption parameters under the example data for the reference of the operator; among them, compared with the working conditions of the traditional design, the low-temperature energy-saving condition of the present invention improves the indoor air quality and the thermal comfort of passengers while saving air-conditioning energy consumption because it increases the introduction of outdoor fresh air, increases the oxygen content of the air, and reduces the carbon dioxide concentration in the station.

[0082] Step 5. The temperature and humidity detector detects the outdoor temperature and humidity, calculates the enthalpy value and feeds it back to the indoor control system;

[0083] Qk = Qn - Qw

[0084] Where Qk is the cooling load W that needs to be handled by the subway central air conditioning system within the large system;

[0085] Qn is the total cooling load W within the large system;

[0086] Qw is the maximum cooling load W that can be handled by the fresh air within the large system. When the outdoor air point falls in zone I, it is calculated according to the minimum fresh air volume. When the outdoor air point falls in zone IV, it is calculated according to the fresh air volume.

[0087] Qw = Gw(hw - hn)

[0088] Hw is the enthalpy value of outdoor air;

[0089] hA is the enthalpy value in the middle of the platform public area;

[0090] Gw is the introduced outdoor fresh air volume;

[0091] Step 6. The indoor control system selects the working condition according to the actual parameters, opens and closes the corresponding valves. The requirements for opening and closing the corresponding valves are to increase the fresh air volume, make the best use of the fresh air to handle the indoor cooling load, and the remaining cooling load is handled by the subway central air conditioning system. The corresponding fresh air valves should be adjustable valves, and the opening degree is adjusted according to the indoor and outdoor enthalpy values. The corresponding central air conditioning system should be able to perform variable frequency control and control according to the remaining indoor cooling load.

[0092] In the above step 6, the opening and closing states of the valves are shown in Table 1:

[0093]

[0094] Table 1

[0095] Some of the opening degrees in the above Table 1 are determined through calculation.

[0096] According to the actual value of Qk, perform variable frequency control on the indoor air conditioner to handle the remaining load with the minimum opening degree.

[0097] Existing subway stations have small fresh air working conditions, fresh air working conditions and energy-saving working conditions. Among them, the energy-saving working conditions are set according to the CO2 concentration in the public area and are applicable to the working conditions when the passenger flow in the subway station is small, without considering the working conditions when the outdoor temperature is lower than the outdoor calculated dry bulb temperature for summer air conditioning. The present invention proposes to use the existing ventilation and air conditioning system in the subway station to set the "low temperature energy-saving working condition". When the enthalpy value of outdoor air is h W>When the return air enthalpy value of the air conditioner hA is greater than and ≤ the designed mixed air enthalpy value hC, but the air temperature is lower than the temperature of the public area, the fresh air volume is increased, the water system flow rate is decreased, part of the outdoor fresh air is used to reduce the indoor air temperature, and at the same time, increasing the fresh air can achieve the function of reducing the CO2 concentration in the public area. In this "low air temperature energy-saving condition", the indoor enthalpy value is reduced by using all fresh air, and the remaining cooling load and moisture load are processed by the combined air conditioner.

[0098] Table 2 is the corresponding table of action relationships

[0099]

[0100] Table 2

[0101] For rainy weather, especially in summer in hot summer and cold winter regions, the outdoor atmospheric pressure in summer is lower than that in winter. The moisture content corresponding to the same dry bulb temperature and relative humidity increases, the wet bulb temperature decreases, and the air enthalpy value increases, so people feel stuffy. This method achieves the purpose of reducing air conditioner energy consumption, reducing the carbon dioxide concentration in the station, and increasing the thermal comfort of passengers by increasing the fresh air volume in rainy weather.

[0102] During the period from May to October, especially in hot summer and cold winter regions, in rainy weather outdoors, the time length when the air temperature is lower than 26°C is relatively long. The outdoor calculated dry bulb temperature for summer air conditioning in hot summer and cold winter regions is mostly greater than 33°C. According to the specification, the calculated air temperature in the public area of the concourse is 30°C, and that of the platform is 29°C. In this temperature situation, if operating with the minimum fresh air volume and turning on the air conditioner in the public area, it will not only cause energy waste, but also the indoor thermal comfort is poor.

[0103] The present invention selects and records the hourly temperature data within the time interval from May to October according to the typical meteorological year data collected and processed by Tsinghua University, and sets the operation strategy of the air conditioner during the summer air conditioning period from May to October for local subway stations according to this temperature data.

[0104] The content described in the embodiments of this specification is only a list of implementation forms of the inventive concept, and is only for illustrative purposes. The protection scope of the present invention should not be regarded as limited to the specific forms stated in this embodiment. The protection scope of the present invention also extends to equivalent technical means that those of ordinary skill in the art can think of according to the inventive concept of the present invention.

Claims

1. An energy-saving method for improving the operating parameters of the air conditioner in a subway station according to meteorological data, characterized in that The method includes the following steps: Step 1. Collect initial basic data information, and the process is as follows: 1) Regional climate parameters given by the specification; 2) Collect the predicted far - term late - peak passenger flow parameters of the subway station; 3) Heat dissipation parameters of the platform screen doors; 4) Parameters of the typical meteorological year of the corresponding region; Step 2. Calculate the number of people in the concourse, the number of people on the platform, as well as the heat dissipation and heat transfer of the platform screen door system; Step 3. Calculate the heat generated by passengers, lighting, light boxes, signs, elevators, vending machines, security inspection systems, and ticket gates in the station's large - system, the heat infiltration at each entrance and exit, stairway, and the convective heat transfer during the parking time; Calculate the moisture production of passengers, side walls, roof, and floor in the station, the moisture load at each entrance and exit, stairway, and the convective moisture load of the platform screen doors; Calculate the air - conditioning parameters and determine the air - conditioning operating condition parameters; Step 4. Draw an enthalpy - humidity diagram from the tA air - conditioning return - air temperature line, hC mixed - air enthalpy line, and hA air - conditioning return - air enthalpy line. Give the range of each operating condition interval from the enthalpy - humidity diagram. The operating conditions include the small - fresh - air condition, the all - fresh - air condition, the energy - saving condition, the low - temperature energy - saving condition, and the ventilation condition; Step 5. The temperature - humidity detector detects the outdoor temperature and humidity, calculates the enthalpy value, and feeds it back to the indoor control system; In the said step 4, the conditions for the fresh air operation mode of Xiao Xin are: the enthalpy value h of outdoor air W > the enthalpy value h of the return air of the air conditioner A ; This operation mode includes an energy-saving operation mode. When the conditions are met: the enthalpy value h of outdoor air W > the enthalpy value h in the middle of the platform public area A and the highest CO2 concentration in the public area < 600 ppm, switch from the fresh air operation mode to the energy-saving operation mode; When the conditions are met: the enthalpy value h of outdoor air W > the enthalpy value h of the return air of the air conditioner A , and the highest CO2 concentration in the public area > 1200 ppm, switch from the energy-saving operation mode to the fresh air operation mode; The conditions for the energy-saving operation mode are: the enthalpy value h of outdoor air W > the enthalpy value h of the air return of the air conditioner A , and the highest CO2 concentration in the public area < 600 ppm; The conditions for the fresh air only mode are: the enthalpy value of outdoor air h W ≤ the enthalpy value of the air return of the air conditioner h A , and the outdoor temperature t W ≥ the supply air temperature t of the air conditioner O ; The conditions for the low-temperature energy-saving operating mode are: the enthalpy value h of the air return of the air conditioner A < the enthalpy value h of the outdoor air W ≤ the designed mixed-air enthalpy value h C , and the outdoor temperature t W < the temperature t in the middle of the platform public area A ; The conditions for the ventilation mode are: the outdoor air temperature t W < the air supply temperature t of the air conditioner O ; Step 6. The indoor control system selects the operating condition according to the actual parameters and opens and closes the corresponding valves. The valves include the fresh - air electric air - volume regulating valve, the air - conditioning electric air - volume regulating valve, the indoor return - air electric air - volume regulating valve, the electric air - volume regulating valve at the confluence of return air and fresh air, and the electric air - volume regulating valve for discharging return air to the outside. The opening and closing requirements of the corresponding valves are to increase the fresh - air volume, make the best use of fresh air to handle the indoor cooling load, and the remaining cooling load is handled by the subway central air - conditioning system. The fresh - air valve is an adjustable valve, and its opening degree is adjusted according to the indoor and outdoor enthalpy values. The central air - conditioning system can be frequency - controlled and is frequency - controlled according to the remaining indoor cooling load.

2. The energy-saving method for improving the air-conditioning operation parameters of a subway station according to meteorological data as claimed in claim 1, wherein In Step 6, the combined air - conditioner in the public area is equipped with a fresh - air electric air - volume regulating valve and an air - conditioning electric air - volume regulating valve. The air - return / air - exhaust fan in the public - area air - conditioner is equipped with an indoor return - air electric air - volume regulating valve, an electric air - volume regulating valve at the confluence of return air and fresh air, and an electric air - volume regulating valve for discharging return air to the outside. The valve settings for each operating condition are as follows: In the small - fresh - air condition, the fresh - air electric air - volume regulating valve is partially open, the air - conditioning electric air - volume regulating valve is partially open, the indoor return - air electric air - volume regulating valve is partially open, the electric air - volume regulating valve at the confluence of return air and fresh air is fully open, and the electric air - volume regulating valve for discharging return air to the outside is closed; In the all - fresh - air condition, the fresh - air electric air - volume regulating valve is fully open, the air - conditioning electric air - volume regulating valve is partially open, the indoor return - air electric air - volume regulating valve is partially open, the electric air - volume regulating valve at the confluence of return air and fresh air is closed, and the electric air - volume regulating valve for discharging return air to the outside is closed; In the energy - saving condition, the fresh - air electric air - volume regulating valve is closed, the air - conditioning electric air - volume regulating valve is partially open, the indoor return - air electric air - volume regulating valve is partially open, the electric air - volume regulating valve at the confluence of return air and fresh air is fully open, and the electric air - volume regulating valve for discharging return air to the outside is closed; In the low-temperature energy-saving condition, the fresh air electric air volume regulating valve is fully opened, the air-conditioning electric air volume regulating valve is partially opened, the indoor return air electric air volume regulating valve is partially opened, the electric air volume regulating valve at the confluence of the return air and the fresh air is closed, and the electric air volume regulating valve at the place where the return air is discharged to the outside is closed; In the ventilation condition, the fresh air electric air volume regulating valve is closed, the air-conditioning electric air volume regulating valve is partially opened, the indoor return air electric air volume regulating valve is partially opened, the electric air volume regulating valve at the confluence of the return air and the fresh air is closed, and the electric air volume regulating valve at the place where the return air is discharged to the outside is fully opened.

3. An energy-saving method for improving the operating parameters of the air conditioner in a subway station according to meteorological data as described in claim 1, characterized in that, In step 6, the central air conditioner operates in variable frequency in the small fresh air condition, stops operating in the all fresh air condition, operates in variable frequency in the energy-saving condition, operates in variable frequency in the low-temperature energy-saving condition, and stops operating in the ventilation condition.

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