CN116461287A

CN116461287A - Automatic control method for air conditioner of special equipment in airport

Info

Publication number: CN116461287A
Application number: CN202310422626.0A
Authority: CN
Inventors: 吴冬冬; 刘绪富; 夏鹏; 刘燕波; 丛晓杰
Original assignee: Weihai Guangtai Airport Equipment Co Ltd
Current assignee: Weihai Guangtai Airport Equipment Co Ltd
Priority date: 2023-04-14
Filing date: 2023-04-14
Publication date: 2023-07-21

Abstract

The invention relates to an automatic control method of an air conditioner of special equipment in an airport, which solves the technical problems that the prior air conditioning system of the special equipment in the airport has two working modes of working and stopping by adopting a fixed frequency working mode, electric energy is wasted, limit protection conditions are extremely easy to trigger, and the service life of the system is reduced.

Description

Automatic control method for air conditioner of special equipment in airport

Technical Field

The invention relates to the technical field of airport special vehicles, in particular to an automatic control method of an air conditioner of airport special equipment.

Background

In the technical field of airport special vehicles, the airport special vehicles gradually realize the conversion of electric power, a power battery is used as a power source of a whole vehicle system, and the requirements of an electric air-conditioning system are met. However, the existing electric air conditioning system adopts the traditional air conditioning system mode, only the compressor is changed into a pure electric compressor, the system shutdown protection mode is realized by only depending on low-temperature protection (icing) of a core body, high-temperature protection (high temperature) of the core body and pressure overpressure protection (overpressure), and particularly, the compressor adopts a fixed-frequency working mode, and the PTC heater works and stops two working modes.

The problem with the above-mentioned modes of operation is that the protection conditions are extreme protection, which can lead to a reduction in the service life of the overall system; the compressor and the PTC are always in a constant frequency working state, limit protection conditions are extremely easy to trigger, meanwhile, the driving comfort can be reduced due to the fact that the air outlet of the evaporator is in a constant air mode, electric energy of the power battery is wasted to the greatest extent, and the whole endurance of the vehicle is affected. In addition, no air door is designed, the air port cannot work in a directional mode, the primary inlet passenger cabin can feel that the effect of an air conditioning system is not obvious, and even the effect of opening an air conditioner cannot be reflected in a short time.

Disclosure of Invention

The invention provides an automatic control method of an air conditioner of an airport special device, which aims to solve the technical problems that a compressor in an air conditioning system of the existing airport special vehicle adopts a fixed-frequency working mode, a PTC heater has two working modes of working and stopping, electric energy is wasted, limit protection conditions are extremely easy to trigger, and the service life of the system is reduced.

The invention provides an automatic control method of an air conditioner of airport special equipment, which comprises the following steps:

firstly, opening an air conditioner switch;

secondly, setting air quantity to be more than 0;

third, whether a defrosting mode is started or not, if so, entering a defrosting mode of the fourth step, otherwise, entering a fifth step;

fourth, defrosting mode:

step 1, automatically starting a condensing fan, and adjusting the air quantity of an evaporating fan to the maximum air quantity;

step 2, when the high-low pressure protection switch does not send out a signal or the outlet air temperature detected by the outlet air temperature sensor does not meet the condition of less than 1 ℃, starting the compressor and operating at the maximum rotating speed;

step 3, when the set temperature is more than or equal to 25 ℃ and the PTC temperature protection switch does not send out a signal, starting PTC and operating with maximum power;

step 4, only keeping the air outlet direction of the air door to blow glass, namely only letting the air outlet 9 of the blown glass to outlet air;

step 5, entering an eleventh step;

fifth, whether the heating mode is started or not, if yes, the heating mode of the sixth step is carried out, otherwise, the seventh step is carried out;

sixth, heating mode:

step 1, whether a PTC temperature protection switch starts a protection function or not, if not, entering a next step 2, and if so, waiting;

step 2, automatically adjusting the air quantity according to the temperature of the passenger cabin and the set temperature;

step 3, looking up a table according to the current air quantity to obtain the current PTC allowable maximum power;

step 4, adjusting PTC working power in a variable frequency mode according to the return air temperature and the set temperature;

step 5, selecting an internal circulation and an air outlet direction by the air door according to the setting;

step 6, entering an eleventh step;

seventh, whether to start a refrigeration mode or not, if so, performing the refrigeration mode of the eighth step, otherwise, entering a ninth step;

eighth step, refrigeration mode:

step 1, automatically starting a condensing fan;

step 2, when the high-low pressure protection switch does not send out a signal or the air outlet temperature detected by the air outlet temperature sensor does not meet the condition of less than 1 ℃, entering step 3;

step 3, starting a compressor, and automatically adjusting the air quantity according to the temperature of the passenger cabin and the set temperature;

step 4, obtaining the allowable maximum rotating speed of the current allowable compressor according to the current air quantity table lookup;

step 5, the working rotation speed of the compressor is adjusted in a variable frequency mode according to the return air temperature and the set temperature;

step 6, selecting an internal and external circulation and an air outlet direction by the air door according to the setting;

step 7, entering an eleventh step;

ninth, the evaporator discharges wind according to the set wind;

tenth, the electric control air door selects the internal and external circulation and the air outlet direction according to the setting;

eleventh, whether the air conditioner switch is turned off or whether the air quantity is 0, if so, entering a twelfth step, otherwise, returning to the third step;

and twelfth, closing the evaporation fan and closing the condensation fan.

The invention has the beneficial effects that the control method for automatic adjustment is additionally arranged in the air conditioner of the special vehicle at the airport, the working mode is flexibly selected according to the actual situation, the air outlet effect is ensured, the electric energy is saved, the service life of the system is prolonged, the use effect of the air conditioner is improved, the duration of the vehicle is improved, and the advantages of automation, intellectualization, energy conservation and the like of an air conditioning system are reflected.

Further features and aspects of the present invention will become apparent from the following description of specific embodiments with reference to the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram of the structural layout of an air conditioning system of an airport specialty appliance;

FIG. 2 is a schematic block diagram of a control system;

fig. 3 is a flowchart of an automatic control method of an air conditioner of an airport special equipment.

The symbols in the drawings illustrate:

1. the system comprises a condenser, an evaporator, a compressor, a PLC, a passenger cabin temperature sensor, an electric control air door, a face blowing air outlet, a foot blowing air outlet, a glass blowing air outlet, a condensing fan and a liquid storage tank.

Detailed Description

The invention will be described in further detail with reference to the accompanying drawings.

The hardware of the control system comprises an operation panel, a controller 4, a PLC controller, a condenser 1, an evaporator 2, a compressor 3, a controller 4, a cabin temperature sensor 5, an electric control air door 6, a face blowing air outlet 7, a foot blowing air outlet 8, a glass blowing air outlet 9, a condensing fan 10, a liquid storage tank 11 and the like.

The operation panel is used as the input of the control command of the air conditioning system, is connected with the PLC controller through a CAN bus or a wire, and sends the required temperature, the required air quantity and the working mode to the PLC controller. The PLC controller is used for controlling the air conditioner to work.

The evaporator 2 is used as air outlet equipment of an air conditioning system, and the PLC controller is used for controlling the air outlet quantity. The evaporator 2 is provided with an outlet air temperature sensor and a return air temperature sensor. The electric control air door 6 is used as a heat dissipation and internal and external circulation switching device of the air conditioning system, and the PLC controls the opening and closing states of the air door to realize the bay circulation control and the wind direction control. The electric control air door 6 is used as a heat dissipation and internal and external circulation switching device of the air conditioning system, and the PLC controls the opening and closing states of the air door to realize internal and external circulation control and wind direction control.

The condenser 1 is used as a heat radiating device of an air conditioning system, and the working start-stop state is controlled by a PLC controller.

The liquid storage tank is used as a refrigerant pressure detection device of an air conditioning system and is provided with a high-low pressure protection switch, signals are directly transmitted to the PLC, and the start-stop state of the compressor is controlled by the PLC.

The compressor 3 is used as a refrigerating power unit of an air conditioning system, and the PLC controls start and stop and variable frequency speed regulation through a CAN bus.

The PTC is used as a heating power unit of the air conditioning system, the PLC controls the heating power and is provided with an over-temperature protection switch, and the PLC controls the start-stop state of the PTC by detecting a switch signal.

The signal inputs of the operation panel include the functions shown in table 1:

table 1:

the exhaust temperature sensor is sampled every 0.5s and continuously sampled. When the temperature detected by the air outlet temperature sensor rises, the calculated value changes by updating 0.5 ℃ every 6 s; when the temperature detected by the outlet air temperature sensor is reduced, the calculated value is changed by updating 0.5 ℃ every 3 s. The parameters of the air outlet temperature sensor are as follows: r25=2.200±3% b 25/50=3500±1% (TBD), when the temperature detected by the outlet air temperature sensor is lower than 1 ℃, it means that the core temperature is too low, the core is frozen, and the compressor working circuit should be cut off.

The return air temperature sensor is sampled every 0.5s and continuously sampled. When the temperature detected by the return air temperature sensor rises, the calculated value changes by updating 0.5 ℃ every 6 s; when the temperature detected by the return air temperature sensor drops, the calculated value changes by updating 0.5 ℃ every 3 s. The parameters of the return air temperature sensor are as follows: r25=2.200±3% b 25/50=3500±1% (TBD) for increasing or decreasing the cooling and heating power by comparing the temperature difference with the set temperature.

When detecting that the over-temperature protection switch on the PTC has a signal, the temperature of the PTC core body is over high, the temperature in the core body exceeds 180 ℃, and the PTC working circuit is cut off.

When the high-low pressure protection switch of the liquid storage tank generates signals, the conditions are divided into the following two cases, if the air-conditioning system is not operated during detection or the last time is operated for 5 minutes, the air-conditioning system is represented to have too low pressure, and the alarm is sent to prompt an operator to repair at the moment; if the air conditioning system is running or within 5min from the last shutdown in detection, the air conditioning system pressure is too high, and the working circuit of the compressor is cut off.

The cabin temperature sensor 5 is sampled every 0.5s and continuously. When the cabin temperature sensor 5 temperature rises, the calculated value changes by updating 0.5 ℃ every 6 s; as the cabin temperature sensor 5 temperature drops, the calculated value changes at 0.5 ℃ every 3s update. The cabin temperature sensor 5 parameters are as follows: r25=2.200±3% b 25/50=3500±1% (TBD) for temperature difference comparison with the set temperature, and real-time adjustment of the air output.

The following describes an air conditioner pre-inspection pre-repair strategy:

when the air conditioning system is not operated or is operated last time until the existing air conditioning system is operated for 5 minutes, detecting that the pressure switch of the liquid storage tank is effective, closing the refrigeration function at the moment, alarming the leakage of the uploaded refrigerant, and prompting an operator to maintain;

in a heating or defrosting mode, if the temperature of the air-out temperature sensor is not increased continuously for 60 seconds, the air-out temperature sensor is alarmed to be out of order, and an operator is prompted to maintain;

when the PTC is in work, the PTC temperature protection switch is effective for 60 seconds, so that the failure of the outgoing air temperature sensor is alarmed, an operator is prompted to maintain, and the PTC heating function is forbidden to be started;

after the air conditioner is started, the working hours of the evaporator, the condenser, the compressor and the PTC can be accumulated, when the maintenance time is reached, early warning is carried out in advance, an operator is prompted to maintain, after detection, the maintenance time can be input again according to the state of the device, and the safe and stable operation of the device is ensured.

The automatic air conditioner control logic of the invention is:

1) Temperature regulation

The temperature range is adjusted and can be set to 16-32 ℃.

2) Air volume adjustment

The air quantity can be regulated, and the air quantity can be set to be 0-100%.

Simultaneously, the air quantity is automatically adjusted according to the indoor temperature and the set temperature:

the air volume in the cooling mode is as follows:

indoor temperature-set temperature (. Degree. C.)	Temperature difference of 1 <	The temperature difference is more than 5 and less than or equal to 1	The temperature difference is less than or equal to-5 and less than or equal to-10	The temperature difference is less than or equal to-10
					Air volume	Shutdown	30％	70％	100％

The air volume in the heating mode is shown in the following table:

indoor temperature-set temperature (. Degree. C.)	The temperature difference is less than or equal to-10	The temperature difference is less than or equal to-5 and less than or equal to-10	The temperature difference is more than 5 and less than or equal to 1	Temperature difference of 1 <
					Air volume	100％	70％	30％	Shutdown

The air volume in defrost mode is as follows:

indoor temperature-set temperature (. Degree. C.)	The temperature difference is less than or equal to-10	The temperature difference is less than or equal to-5 and less than or equal to-10	The temperature difference is more than 5 and less than or equal to 1	Temperature difference of 1 <
					Air volume	100％	100％	100％	100％

In the refrigerating, heating or defrosting mode, the closing time of the evaporating fan is delayed for 3s, and residual cold and heat are completely blown out, so that the service life is prolonged.

3) Refrigeration mode

In the refrigeration mode, the air quantity is not zero, the compressor is allowed to work, and the condensing fan is started.

In order to avoid frequent start and stop of the compressor, a compressor protection function is added, namely, the on-off time interval of the compressor is 30s. The delay protection working logic is as follows:

(1) When the temperature of the evaporation core body is less than or equal to 1 ℃, the compressor is closed, and timing is started at the same time; when the temperature of the evaporating core body is raised to be more than or equal to 4 ℃ and the timing is met for 30 seconds, the working state of the compressor is automatically restored;

(2) After the high-low voltage switch is detected to be disconnected, the compressor stops working; when the switch is turned on, the time is delayed for 30 seconds and then the working state is achieved;

the rotating speed of the compressor is automatically adjusted according to the return air temperature and the set temperature:

meanwhile, the rotation speed of the compressor needs to be limited by combining a wind shield:

air volume	30％	70％	100％
				Allowing the compressor to rotate at maximum speed (rpm)	2500	3500	4500

4) Heating mode

In the heating mode, PTC is allowed to work only when the air quantity is not zero.

When the PTC over-temperature protection switch (high-temperature protection) is detected, the PTC operation is stopped immediately, and the PTC operation is resumed after the over-temperature protection switch is resumed.

Meanwhile, heating power is automatically started according to the return air temperature and the set temperature, and the following table is provided:

return air temperature-set temperature (DEG C)	The temperature difference is less than or equal to-3	The temperature difference is less than or equal to-3 and less than or equal to-1	The temperature difference is more than or equal to-1 and less than or equal to 1	Temperature difference of 1 <
					PTC power	100％	70％	30％	Shutdown

Meanwhile, the PTC power is limited by combining a wind shield:

air volume	30％	70％	100％
				Allowing PTC maximum power	30％	70％	100％

5) Defrosting mode

In the defrost mode, the compressor needs to continue to execute the repeated start protection command and the PTC executes the over-temperature protection command. Meanwhile, if the set temperature is less than 25 ℃, only the compressor is started, the maximum rotation speed of the compressor is reached, the air speed of the evaporation fan is 100%, and the condensation fan is fully started; if the set temperature is more than or equal to 25 ℃, simultaneously starting the compressor and the PTC, the maximum rotation speed of the compressor and the maximum power of the PTC, the air speed of the evaporating fan is 100%, and the condensing fan is fully opened.

5) Air-out mode

The circulation mode can be set up internal circulation, external circulation, and the air-out direction can be set up glass, head and foot. The local temperature state can be quickly changed according to the selection state of an operator, and the expected effect can be quickly achieved.

Accordingly, the overall air conditioner automatic control method includes the steps of:

first, an air conditioner switch is turned on.

And secondly, setting the air quantity to be more than 0.

And thirdly, whether a defrosting mode is started or not, if so, entering a defrosting mode of the fourth step, and otherwise, entering a fifth step.

Fourth, defrosting mode.

Step 1, automatically starting a condensing fan, and automatically adjusting the air quantity of an evaporation fan to the maximum air quantity.

And 2, starting the compressor and operating at the maximum rotating speed when the high-low pressure protection switch does not send out a signal or the air outlet temperature detected by the air outlet temperature sensor does not meet the condition of less than 1 ℃.

And step 3, when the set temperature is more than or equal to 25 ℃ and the PTC temperature protection switch does not send out a signal, starting PTC and operating with maximum power.

And 4, only keeping the air outlet direction of the air door to blow glass, namely only letting the air outlet 9 of the blown glass to outlet air.

Step 5, entering an eleventh step.

and sixthly, heating the mode.

and step 3, looking up a table according to the current air quantity to obtain the current PTC allowable maximum power.

And 4, adjusting the PTC working power in a variable frequency mode according to the return air temperature and the set temperature.

And 5, selecting an internal circulation and an air outlet direction by the air door according to the setting.

And 6, entering an eleventh step.

And seventh, whether to start a refrigeration mode, if so, performing the refrigeration mode of the eighth step, otherwise, entering the ninth step.

Eighth, a refrigeration mode.

And 1, automatically starting a condensing fan.

and 6, selecting an internal and external circulation and an air outlet direction by the air door according to the setting.

And 7, entering an eleventh step.

And ninth, the evaporator discharges wind according to the set wind.

And tenth, the electric control air door selects the internal and external circulation and the air outlet direction according to the setting.

Eleventh, whether the air conditioner switch is turned off or whether the air quantity is 0, if so, the twelfth step is carried out, and otherwise, the third step is returned.

And twelfth, closing the evaporation fan and closing the condensation fan.

Therefore, the control method ensures the air outlet effect, prolongs the service life of the system, improves the use effect of the air conditioner, improves the endurance of the vehicle, and reflects the advantages of automation, intellectualization, energy conservation and the like of the air conditioning system.

The above description is only for the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the scope of the claims of the present invention should fall within the protection scope of the present invention.

Claims

1. An automatic control method of an air conditioner of an airport special device is characterized by comprising the following steps: