An air conditioning control method for adjusting fresh air volume in combination with carbon dioxide content in a vehicle

Abstract

A kind of air conditioning control method of adjusting fresh air volume in combination with carbon dioxide content in vehicle, including carbon dioxide sensor, the carbon dioxide sensor is set at air conditioning unit return air inlet, the present application has the advantages and progress relative to prior art: more accurate adjustment air conditioning fresh air valve opening further adjustment vehicle indoor fresh air volume to improve the air quality in vehicle, ensure that vehicle indoor fresh air not only can satisfy vehicle load demand, simultaneously can make carbon dioxide concentration value in vehicle in standard range, reduce the reason caused by carbon dioxide concentration in vehicle is too high passenger comfort in vehicle reduces, complaint increases, in addition, when load signal or carbon dioxide monitoring signal has one failure, another signal monitoring data can be used to realize air conditioning fresh air volume control adjustment, provide redundant control scheme for fresh air control.

Description

Technical Field

[0001] This invention relates to an air conditioning system for urban rail transit vehicles, and more particularly to an air conditioning control method that adjusts the fresh air volume based on the carbon dioxide content inside the vehicle. Background Technology

[0002] In the load calculation of air conditioning systems in urban rail transit vehicles, the air conditioning fresh air load and passenger heat dissipation load account for about 85%-95% of the total vehicle cooling load, which is a huge proportion among all loads affecting air conditioning. According to the cooling load calculation, urban rail transit vehicles currently mainly adopt the control method of adjusting the fresh air volume according to the passenger load to ensure that the fresh air volume in the vehicle meets the load requirements and achieves the purpose of energy saving. Variable fresh air control aims to adjust the opening of the fresh air damper of the air conditioning unit according to the passenger number information, reduce the excessive consumption of fresh air volume, and achieve fresh air regulation.

[0003] According to relevant regulations, the volumetric concentration of carbon dioxide in the passenger compartment should not exceed 1500 ppm. This value is set below the comfort level. The change in the carbon dioxide concentration in the vehicle depends on the following differential equation:

[0004]

[0005] in

[0006] Cint(t): The carbon dioxide concentration in the bus at time t [ppm]

[0007] Cext: Concentration of carbon dioxide in fresh air [ppm]

[0008] V: The volume of the carriage, which is the vehicle volume minus the passenger volume [m3]

[0009] Qf: Fresh air flow rate [m³ / h]

[0010] N: Number of people

[0011] QPers: Per capita carbon dioxide emissions [l / h]

[0012] Given Cext=400ppm and QPers=17.5l / h, without considering the impact of door opening and closing on the carbon dioxide concentration inside the vehicle, the carbon dioxide concentration gradually increases with time t. When t reaches a certain value, the carbon dioxide concentration inside the vehicle tends to reach equilibrium. Based on the above formula and calculations using the passenger load and fresh air volume of urban rail transit vehicles, it can be seen that simply adjusting the fresh air volume based on the load signal, even considering the impact of airflow during door opening and closing on the air quality inside the vehicle, can easily cause the carbon dioxide content inside the vehicle to rise above 1500ppm when the number of passengers is excessive or the distance between platforms is long. This reduces passenger comfort. Therefore, inventing a control scheme that adjusts the fresh air volume of the air conditioning unit according to the carbon dioxide content inside urban rail transit vehicles to improve air quality and enhance passenger comfort is an urgent problem to be solved. Summary of the Invention

[0013] The purpose of this invention is to improve the air quality inside the vehicle and enhance passenger comfort by adjusting the fresh air volume of the air conditioning unit.

[0014] To achieve the above objectives, the present invention provides an air conditioning control method for adjusting the fresh air volume based on the carbon dioxide content inside the vehicle, including a carbon dioxide sensor installed at the return air vent of the air conditioning unit. The control method is as follows:

[0015] The carbon dioxide sensor detects the carbon dioxide concentration inside the vehicle and uploads the carbon dioxide concentration data to the air conditioning unit controller via network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. When the detected carbon dioxide concentration reaches the set value, the TCMS network feeds back a control signal to the air conditioning controller, which then adjusts the fresh air volume by controlling the opening of the fresh air valve. At this time, the opening of the fresh air valve can still be controlled in conjunction with the current load signal. That is, when the load signal requires the fresh air valve to be greater than the set opening, control is executed according to the load signal.

[0016] Specific control measures include:

[0017] (1) The carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is ≤700 ppm and the overall monitoring value is on an upward trend. The carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller. The air conditioning controls the fresh air valve opening to 1 / 3. At this time, the fresh air valve opening can still be controlled in combination with the current load signal. That is, when the load signal requires the fresh air valve opening to be greater than 1 / 3, the control is executed according to the load signal.

[0018] (2) The carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is between 700 and 1500 ppm and the overall monitoring value is on an upward trend. The carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller. The air conditioning controls the fresh air valve opening from 1 / 3 to 2 / 3. When the load signal in this concentration range requires the fresh air valve opening to be greater than 2 / 3, control is executed according to the load signal.

[0019] (3) The carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is >1500 ppm and the overall monitoring value is on an upward trend. The carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller, and the air conditioning controls the fresh air valve to operate from 2 / 3 opening to the maximum opening.

[0020] (4) The carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is between 600 and 1400 ppm and the overall monitoring value is decreasing. The carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller. The air conditioning controls the fresh air valve opening from fully open to 2 / 3. When the load signal in this concentration range requires the fresh air valve opening to be greater than 2 / 3, control is executed according to the load signal.

[0021] (5) When the carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is ≤600 ppm and the overall monitoring value is in a downward trend, the carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller via network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller, and the opening of the air conditioning control fresh air valve changes from 2 / 3 to 1 / 3. At this time, when the load signal requires the fresh air valve opening to be greater than 1 / 3, the control is executed according to the load signal.

[0022] Advantages and advancements of this invention compared to existing technologies:

[0023] Because adjusting the fresh air volume based on carbon dioxide concentration monitoring values ​​is more accurate and provides a more direct reflection of in-vehicle air quality compared to adjusting it based on load signals, the air conditioning control system combines a load-based fresh air volume control scheme with a carbon dioxide-based scheme. This allows for more precise adjustment of the air conditioning fresh air valve opening, thereby regulating the in-vehicle fresh air volume to improve air quality. This ensures that the fresh air intake not only meets the vehicle's load requirements but also keeps the in-vehicle carbon dioxide concentration within the standard range, reducing passenger comfort and complaints caused by excessively high carbon dioxide levels. Furthermore, if either the load signal or the carbon dioxide monitoring signal fails, the other signal can be used to control the air conditioning fresh air volume, providing a redundant control scheme. Attached Figure Description

[0024] Figure 1 A schematic diagram showing the installation location of the carbon dioxide sensor in an air conditioning unit;

[0025] Figure 2 The principle of adjusting the fresh air volume control of the air conditioner to monitor the carbon dioxide content inside the vehicle;

[0026] Figure 3 The fresh air door control scheme was adjusted based on the carbon dioxide content inside the vehicle.

[0027] In the diagram: 1-Carbon dioxide sensor; 2-Air conditioner return air vent. Detailed Implementation

[0028] Based on the conventional air conditioning control scheme that adjusts the fresh air volume according to the load signal, a carbon dioxide monitoring device, namely carbon dioxide sensor 1, is introduced to monitor the carbon dioxide content in the vehicle's air in real time. Carbon dioxide sensor 1 can be installed at the air return vent 2 of the air conditioning unit (see...). Figure 1 It can also be installed inside the vehicle to achieve real-time and accurate monitoring of carbon dioxide concentration in the in-vehicle air quality. Based on the monitored CO2 concentration data, the vehicle control system automatically controls the opening of the air conditioning unit's fresh air valve to adjust the amount of fresh air, ensuring that the carbon dioxide level inside the vehicle is within a comfortable range to meet the comfort needs of passengers.

[0029] The control principle of adjusting fresh air volume based on the carbon dioxide content inside the vehicle is as follows: Figure 2 The carbon dioxide sensor 1 detects the carbon dioxide concentration data inside the vehicle and uploads it to the air conditioning unit controller via network communication. The controller then uploads the data to the vehicle TCMS network. By pre-setting the carbon dioxide content value that triggers fresh air adjustment in the TCMS network, when the detected carbon dioxide concentration reaches the set value, the TCMS network feeds back a control signal to the air conditioning controller, and then adjusts the fresh air volume by controlling the opening of the fresh air valve.

[0030] For specific control schemes, please refer to... Figure 3 The carbon dioxide concentration and fresh air valve opening settings in the control scheme can be adjusted according to the specific circuit and fresh air valve selection; the specific scheme includes:

[0031] (1) Carbon dioxide sensor 1 detects that the carbon dioxide concentration in the vehicle body is ≤700 ppm and the overall monitoring value is on an upward trend. Carbon dioxide sensor 1 uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller. The air conditioning controls the fresh air valve opening to 1 / 3. At this time, the fresh air valve opening can still be controlled in combination with the current load signal. That is, when the load signal requires the fresh air valve opening to be greater than 1 / 3, the control is executed according to the load signal.

[0032] (2) Carbon dioxide sensor 1 detects that the carbon dioxide concentration in the vehicle body is between 700 and 1500 ppm, and the monitored value is generally on an upward trend. Carbon dioxide sensor 1 uploads the carbon dioxide concentration data to the air conditioning unit controller via network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller. The air conditioning controls the fresh air valve opening from 1 / 3 to 2 / 3. When the load signal in this concentration range requires the fresh air valve opening to be greater than 2 / 3, control is executed according to the load signal.

[0033] (3) Carbon dioxide sensor 1 detects that the carbon dioxide concentration in the vehicle body is >1500 ppm and the monitoring value is generally on an upward trend. Carbon dioxide sensor 1 uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller, and the air conditioning controls the fresh air valve to operate from 2 / 3 opening to the maximum opening.

[0034] (4) Carbon dioxide sensor 1 detects that the carbon dioxide concentration in the vehicle body is between 600 and 1400 ppm and the overall monitoring value is decreasing. Carbon dioxide sensor 1 uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller. The air conditioning control changes the opening of the air valve from fully open to 2 / 3. When the load signal in this concentration range requires the fresh air valve opening to be greater than 2 / 3, the control is executed according to the load signal.

[0035] (5) When carbon dioxide sensor 1 detects that the carbon dioxide concentration in the vehicle body is ≤600 ppm and the overall monitoring value is in a downward trend, carbon dioxide sensor 1 uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication. The air conditioning unit controller then uploads the data to the vehicle TCMS network. By setting the carbon dioxide content value that triggers fresh air adjustment in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller, and the opening of the air conditioning control fresh air valve changes from 2 / 3 to 1 / 3. At this time, when the load signal requires the fresh air valve opening to be greater than 1 / 3, the control is executed according to the load signal.

Claims

1. An air conditioning control method of adjusting fresh air volume in combination with carbon dioxide content in a vehicle, characterized by: The control method comprises a carbon dioxide sensor arranged at an air conditioning unit return air inlet. The carbon dioxide sensor detects the carbon dioxide concentration in the vehicle body, and uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication, and the air conditioning unit controller uploads the data to the vehicle TCMS network. The specific control scheme comprises: (1) When the carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is less than or equal to 700 ppm, and the monitored value is in an overall upward trend, the carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication, and the air conditioning unit controller uploads the data to the vehicle TCMS network, and the TCMS network feeds back a control signal to the air conditioning unit controller, and the air conditioning unit controls the new air valve opening degree to be 1 / 3, and the new air valve opening degree can still be controlled in combination with the current load signal, that is, when the load signal requires the new air valve opening degree to be greater than 1 / 3, the control is performed according to the load signal; (2) When the carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is between 700 ppm and 1500 ppm, and the monitored value is in an overall upward trend, the carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication, and the air conditioning unit controller uploads the data to the vehicle TCMS network, and the TCMS network feeds back a control signal to the air conditioning unit controller, and the air conditioning unit controls the new air valve opening degree to be 2 / 3, and when the load signal requires the new air valve opening degree to be greater than 2 / 3 in this concentration range, the control is performed according to the load signal; (3) When the carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is greater than 1500 ppm, and the monitored value is in an overall upward trend, the carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication, and the air conditioning unit controller uploads the data to the vehicle TCMS network, and the TCMS network feeds back a control signal to the air conditioning unit controller, and the air conditioning unit controls the new air valve to be operated at the maximum opening degree. (4) The carbon dioxide sensor detects that the carbon dioxide concentration in the vehicle body is between 600-1400 ppm, and the overall monitoring value is in a downward trend. The carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication, the air conditioning unit controller uploads the data to the vehicle TCMS network, sets the carbon dioxide content value triggering fresh air regulation in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller, and the air conditioning control fresh air valve opening degree is changed from full opening to 2 / 3. When the load signal requires fresh air valve opening degree greater than 2 / 3, execute according to the load signal control; (5) The carbon dioxide sensor detects that the carbon dioxide concentration value in the vehicle body is ≤600 ppm, and the overall monitoring value is in a downward trend. The carbon dioxide sensor uploads the carbon dioxide concentration data to the air conditioning unit controller through network communication, the air conditioning unit controller uploads the data to the vehicle TCMS network, sets the carbon dioxide content value triggering fresh air regulation in advance in the TCMS network, the TCMS network feeds back the control signal to the air conditioning unit controller, and the air conditioning control fresh air valve opening degree is changed from 2 / 3 to 1 / 3. At this time, when the load signal requires fresh air valve opening degree greater than 1 / 3, execute according to the load signal control.

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