JPH09178249A - Vav control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent loss of energy by stabilizing control to keep a load reset control from disturbing air conditioning. SOLUTION: In a VAV controller master 23, a total control status is determined based on a control status from VAV controllers 10-1-10-n and the total control status determined is sent to an air conditioning equipment controller 7. The air conditioning equipment controller 7 determines an air conditioning status from a set value TSsp of the current temperature of blown supplied air and a measured value TRpv of the temperature of circulated air while deciding the direction of change in the temperature of the circulated air from the measured value TRpv of the temperature of the circulated air and a primary delay temperature TRpv '. The set value TSsp of the temperature of the blown supplied air is determined based on the air conditioning status, the direction of change in the temperature of the circulated air and the total control status from the VAV controller master 23 thus obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention controls the amount of supply air to the controlled area according to the load condition of the controlled area.
When the load condition of the controlled area falls into an unsatisfactory state, the capacity of the air supply temperature from the air conditioner is increased (load reset) to eliminate the unsatisfactory condition of the load condition.
The present invention relates to an AV control system.

[0002]

2. Description of the Related Art Conventionally, in a large-scale building, when air is supplied from an air conditioner to each part via an air supply duct, it is variable for each air supply outlet of each air conditioning target part (controlled area). An air supply amount adjusting unit (hereinafter referred to as a VAV unit) is provided, and the air supply amount from the VAV unit is controlled according to the load situation of the controlled area.
Even if one of the load conditions in the controlled area falls into an unsatisfactory state even if the damper opening of the VAV unit is at the MAX value (100% air volume), the capacity of the supply air temperature from the air conditioner is increased. In order to eliminate the unsatisfactory state of the load situation. Generally, such an increase in the capacity of the blown air supply temperature is called a load reset.

In recent years, in order to efficiently perform load reset, the load status of the entire controlled area is judged from the control status of each VAV unit and the control status of the air conditioner,
A method of determining the temperature of air supplied from the air conditioner based on this is being adopted.

[0004]

However, in this system which is being adopted recently, the control state of the air conditioner is obtained from the valve output value to the air conditioner, so that the temperature effect does not actually appear. Nevertheless, the load condition may be determined as the temperature effect is manifesting, and the blow-off air supply temperature may be determined in a direction contradictory to the room temperature request. In this case, the load reset control becomes a disturbance of the air conditioning, the control becomes unstable, and energy is lost.

The present invention has been made to solve such a problem, and its object is to prevent load reset control from becoming a disturbance of air conditioning, to stabilize the control, and to prevent energy loss. V that can be done
It is to provide an AV control system.

[0006]

In order to achieve such an object, the first invention (the invention according to claim 1) is to receive the supply of blown air from an air conditioner, and to receive the first to Nth objects. First to N-th variable air supply amount adjusting means for controlling the amount of air supply to each of the control areas according to the load condition of the control area, and the first to Nth
The total control status is obtained from the control status sent from the variable air supply amount adjusting means
The direction of change of the temperature index that indicates the overall temperature state in the controlled area is determined, and the outlet air supply temperature from the air conditioner is determined based on the determined direction of change of the temperature index and the total control status. A supply air temperature determining means is provided. According to the present invention, the total obtained from the direction of change of the temperature index indicating the comprehensive temperature state in the first to Nth controlled areas and the control status from the first to Nth variable air supply amount adjusting means. The temperature of blown air supply from the air conditioner is determined based on the control status.

[0007] The second invention (the invention according to claim 2) is the first invention.
In the invention, the temperature of the air supplied from the air conditioner can be changed by manual operation. According to the present invention, it is possible to reset (manual reset) the blow-off air supply temperature from the air conditioner by a manual operation.

The third invention (the invention according to claim 3) is the first invention.
In the invention, the temperature index indicating the overall temperature state in the first to Nth controlled areas is the temperature of the return air returned to the air conditioner. According to the present invention, based on the direction of change of the return air temperature and the total control status,
The blow-off air supply temperature from the air conditioner is determined.

The fourth invention (the invention according to claim 4) is the first
In the invention, the temperature index indicating the overall temperature state in the first to Nth controlled areas is a weighted average of the environmental temperatures in the first to Nth controlled areas. According to the present invention, the blow-off air supply temperature from the air conditioner is determined based on the direction of change in the weighted average of the environmental temperatures in the first to Nth controlled areas and the total control status.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail based on embodiments. FIG. 1 is an instrumentation diagram of a VAV control system showing an embodiment of the present invention. In the figure,
An air conditioner 1 includes a cooling coil 3 to which cold water CW is supplied via an electric valve 2, a heating coil 5 to which hot water HW is supplied via an electric valve 4, and a blower 6. In the blower 6, 6a is a fan and 6b is an inverter.

The operation of the inverter 6b, the motor-operated valve 2 and the motor-operated valve 4 in the air conditioner 1 is controlled by an air conditioner controller (IDC) 7, and the air supply from the fan 6a of the air conditioner 1 is supplied. Air (blow-off air supply) passes through the air supply duct 8 and the controlled areas 9-1 to 9-1.
9-n. Controlled area 9
-1 to 9-n are provided with temperature sensors T1 to Tn that detect the room temperature for each area.
The detected temperature PV at 1 is given to each locally provided VAV controller (IRC) 10-1 to 10-n.

VAV controllers 10-1 to 10-n
Calculates the required air volume to the controlled areas 9-1 to 9-n based on the deviation between the detected temperature PV and the set temperature SP given to each of them, and calculates the required air volume to the VAV controller master (IRC).
M) 23 to return to the air conditioner controller 7 while ensuring the required air volume, the VAV unit 1
The opening degrees of the dampers 12-1 to 12-n of the 1-1 to 11-n are controlled while observing the detected forces of the wind speed sensors 13-1 to 13-n. The air conditioner controller 7 obtains the total required air volume of the entire system from the required air volumes sent from the VAV controllers 10-1 to 10-n, and the rotation speed of the fan 6a of the air conditioner 1 is ensured to secure this total required air volume. To control. In the VAV units 11-1 to 11-n, 14-1 to 14-n are opening degree sensors that detect the opening degrees of the dampers 12-1 to 12-n.

Further, VAV controllers 10-1 to 10
-N determines the control status as a room temperature request (VAV control state) as described later, and sends the determined control status to the VAV controller master 23. V
The AV controller master 23 is the VAV controller 1
From the control statuses from 0-1 to 10-n, a total control status is obtained as a VAV comprehensive control state as described later, and the obtained total control status is sent to the air conditioner controller 7. The air conditioner controller 7 is a VAV
Based on the total control status sent from the controller master 23, the cooling / heating status described later, and the direction of change in the return air temperature (state of the return air temperature), the set value TS _sp of the blown air supply temperature from the air conditioner 1 is set. decide.

In this embodiment, the set value TS _sp of the blow-off air supply temperature in the air conditioner controller 7 is
It can be changed by manual operation. That is, the set value TS _sp of the blow-off air supply temperature from the air conditioner 1 is usually automatically determined by the air conditioner controller 7, but it is artificially changed by using a setting changing means such as a keyboard if necessary. (Manual reset) is supposed to be possible.

On the other hand, the VAV units 11-1 to 11-n
, And blown out to the controlled areas 9-1 to 9-n through the blowout ports 15-1 to 15-n (supply air blowout)
After returning to the air-conditioning control in the controlled areas 9-1 to 9-n, return air duct 1 from the exhaust ports 16-1 to 16-n.
7, and is discharged through the exhaust adjustment damper 18.
A part thereof is returned to the air conditioner 1 as return air via a return air adjustment damper 19. Then, with respect to the return air returned to the air conditioner 1, the outside air is the outside air adjusting damper 20.
It is taken in through a predetermined ratio via.

The opening degrees of the exhaust adjustment damper 18, the return air adjustment damper 19, and the outside air adjustment damper 20 are adjusted by a command from the air conditioner controller 7. Further, the measured value TS _pv of the blown supply air temperature from the air conditioner 1 and the measured value TR _pv of the return air temperature in the return air duct 17 are given to the air conditioner controller 7 via the temperature sensors 21 and 22. The air conditioner controller 7
The measured value TR _{pv of the} temperature of the air supplied from the air conditioner 1 is the set value T
The valve output is output and the opening degree of the motor-operated valve 2 and the motor-operated valve 4 is controlled so as to match S _sp .

[Determination of Control Status by VAV Controller] VAV Controller 10 (10-1 to 10-)
The control status in n) is determined as follows.
The VAV controller 10 detects the detected temperature PV and the set temperature S.
PID calculation is performed from P (cooling set temperature CSP, heating set temperature HSP) to generate a control output (VAV output) to the VAV unit 11. This allows the VAV unit 1
The opening degree of the damper 12 of No. 1 is controlled.

Here, the VAV controller 10 has the opening (VA) of the damper 12 detected by the opening sensor 14.
Based on the V damper opening), the detected temperature PV, and the set temperature SP, control statuses “1” to “5” as shown in FIG.
To determine. Note that the VAV controller 10 sets the control status to “0” if it is stopped.

The control statuses "0" to "5" indicate the indoor temperature request (VAV control status), and their meanings differ depending on the cooling / heating status determined by the air conditioner controller 7 (see FIG. 3). . That is, if the cooling / heating status is the cooling mode, the control statuses “0”, “1”, “2”, “3”, “4”, and “5” are “stop”, “cooling increase”, “cooling in progress”. , "Energy saving",
"Cooling weak", "cooling down" means "stop", "heating down", "heating weak", if the cooling / heating status is heating mode.
It means "energy saving", "heating", "increasing heating".

[Determination of Total Control Status by VAV Controller Master] VAV Controller Master 23
The total control status in is determined as follows. The control status determined by the VAV controllers 10-1 to 10-n is sent to the VAV controller master 23. The VAV controller master 23 obtains the total control status as shown in FIG. 4 from the control status sent from the VAV controllers 10-1 to 10-n.

That is, in case No. In "1", the control statuses "4" and "5" do not exist, and if at least one control status "1" exists, the control status "2",
Regardless of the presence of "3", the total control status is "1". In addition, case NO. In the case of 2, if the control status “5” does not exist and there is at least one of the control statuses “1” and “4”, the control status “2”,
Regardless of the existence of "3", the total control status is "2".

In the same manner, the case No. In "3", the total control status is calculated as "2", and the case No. For “4”, “5”, “6”, “7”, and “11”, the total control status is calculated as “3”, and the case N
O. For "8" and "9", the total control status is calculated as "4", and the case No. In the case of "10", the total control status is obtained as "5", and the case No. "1
In "2", the total control status is calculated as "0". In FIG. 4, “○” means “exists”,
"-" Indicates "may or may not exist", and "x" indicates "not exist".

This total control status "0"-
“5” indicates a temperature request for the entire VAV (VAV comprehensive control state), and its meaning depends on the cooling / heating status determined by the air conditioner controller 7 (see FIG. 3). That is, if the cooling / heating status is the cooling mode, the total control status "0", "1",
"2", "3", "4", "5" means "stop", "cooling up", "cooling", "energy saving", "cooling weak", "cooling down", and cooling / heating status If is in heating mode, "Stop", "Heating reduced", "Heating weak", "Energy saving",
It means “during heating” and “increases heating”.

[Determination of Cooling / Heating Status in Air Conditioner Controller] The air conditioning controller 7 determines the cooling / heating status from the current set value TS _sp of the outlet air supply temperature and the measured value TR _{pv of the} return air temperature. That is, as shown in FIG.
The set value TS _sp of the outlet air supply temperature is the measured value TR _{pv of the} return air temperature.
If it is lower than (TS _sp <TR _pv ), the cooling / heating status is determined as the cooling mode. Outlet air supply temperature setting value TS
_{If sp} is higher than the measured return temperature TR _pv (TS _sp ＞
TR _pv ), determine the heating / cooling status as the heating mode. This makes it possible to accurately determine whether the air conditioner 1 is currently performing the cooling operation or the heating operation.

In this case, in summer, the "cooling status" is set for the whole day. In the winter, the heating status is changed from 10 am to 11 am in the morning, and then switched to the cooling status. After that, the interior of the room becomes a cooling load due to a work station, a person, lighting, or the like, and therefore the switching does not occur again.

[Determination of Direction of Change of Return Air Temperature in Air Conditioner Controller] The air conditioner controller 7 determines the direction of change of the return air temperature by monitoring the vertical change of the return air temperature. In this embodiment, the up-down fluctuation of the return air temperature is determined by comparing the return air temperature with a first delay.

That is, the air conditioner controller 7 passes the measured value TR _pv of the return air temperature through the first-order lag filter realized by software to obtain the first-order lag return air temperature TR _pv ′. In this case, the following equation (1) is used as the first-order delay calculation equation. In this equation (1), U ₀ is the previous output,
U is the current output, T _S is the execution cycle, T ₁ is the time constant (delay time), and V is the current input. U = U ₀ + {T _S / (T _S + T ₁ )} · (V−U ₀ ) ... (1)

Then, the air conditioner controller 7 compares the primary delayed return air temperature TR _pv 'with the return air temperature measurement value TR _pv to determine the direction of change of the return air temperature. FIG. 6 shows the situation in which the direction of change in the return air temperature is determined, and the difference ΔTR between TR _pv 'and TR _pv (ΔTR = TR _pv ' −TR _pv ) is −0.5 ≦ Δ.
If TR ≦ + 0.5 ° C., the direction of change of the return air temperature is “no change ()”. On the other hand, ΔTR <-
When the temperature is 0.5 ° C., the direction of change in the return air temperature is the “upward direction ()”, and when + 0.5 ° C. <ΔTR, the direction of change in the return air temperature is the “downward direction ()”. In addition, in this embodiment, at the time of transition from “downward direction” to “no change” and from “upward direction” to “no change”,
A hysteresis of 0.2 ° C is provided.

7A and 7B, the measured value TR _pv of the return air temperature and 1 for the measured value TR _pv of the return air temperature are shown.
The change situation of the next-delay return air temperature TR _pv 'is illustrated. In this example, the measured value TR _pv of the return air temperature changes stepwise, while the first-order delayed return air temperature TR _pv ′ follows the delay. In this case, at time t1, since TR _pv '≈ TR _pv , the direction of change of the return air temperature is "no change ()".
It is said. At time t2, since TR _pv '<TR _pv , the direction of change of the return air temperature is set to "increase direction ()". At time t3, since TR _pv '> TR _pv , the direction of change in the return air temperature is set to the “falling direction ()”.

[Determination of Outlet Air Supply Temperature by Air Conditioner Controller] The total control status from the VAV controller master 23 is sent to the air conditioner controller 7. The air conditioner controller 7 determines the set value TS _sp of the blown air supply temperature based on the cooling / heating status and the direction of change of the return air temperature determined as described above, and the total control status sent from the VAV controller master 23.

FIG. 8A shows the relationship between the total control status when the cooling / heating status is the heating mode, the direction of change of the return air temperature, and the setting change value of the blow-off air supply temperature.
(B) shows the relationship between the total control status when the cooling / heating status is the cooling mode, the direction of change of the return air temperature, and the setting change value of the blow-off supply air temperature. In this figure,
Direction of change of return air temperature ,, symbol "↑",
It is expressed as “≒” and “↓”.

[When the cooling / heating status is the heating mode (TS _sp > TR _pv )] When the direction of the change of the return air temperature is the rising direction, the blowout / supply of the total control status “1 (heating reduced)” is performed. Change the air temperature setting change value to "-
2.0 ° C ", and the setting change value of the blow-off air supply temperature is" ± 0 "for the total control status" 5 (increase heating) ".
℃ ”. As a result, when the return air temperature is increasing in the heating mode, the set value TS _sp of the outlet air supply temperature is greatly reduced with respect to the temperature request for "heating reduced", and the temperature request for "heating increased". On the other hand, the set value T of the outlet air supply temperature
S _sp maintains the current status.

When the return air temperature changes in the downward direction, the total control status is set to "+ 2.0.degree. C." for the total control status "5 (increase heating)". The setting change value of the blow-off air supply temperature is set to "± 0 ° C" for the status "1 (heating reduced)". As a result, when the return air temperature is decreasing in the heating mode, the set value TS _sp of the outlet air supply temperature is greatly increased with respect to the temperature request for "heating increase", and the temperature request for "heating reduction" is achieved. On the other hand, the set value TS _sp of the blown air supply temperature is maintained as it is.

[When the cooling / heating status is the cooling mode (TS _sp <TR _pv )] When the direction of the change of the return air temperature is the rising direction, the blowout / supply of the total control status “1 (cooling increase)” is performed. Change the air temperature setting change value to "-
2.0 ° C. ”, and the setting change value of the outlet air supply temperature is set to“ ± 0 ”for the total control status“ 5 (cooling down) ”.
℃ ”. As a result, when the return air temperature is increasing in the cooling mode, the set value TS _sp of the blown air supply temperature is greatly reduced with respect to the temperature demand of "cooling increase", and the temperature demand of "cooling reduction" is achieved. On the other hand, the set value T of the outlet air supply temperature
S _sp maintains the current status.

When the return air temperature changes in a downward direction, the total control status is set to "+ 2.0 ° C" for the total control status "5 (cooling down)". For the status "1 (cooling increase)", the setting change value of the blown air supply temperature is set to "± 0 ° C". As a result, when the return air temperature is decreasing in the cooling mode, the set value TS _sp of the blown air supply temperature is greatly increased with respect to the temperature requirement of “cooling reduction”, and the temperature requirement of “cooling increase” becomes. On the other hand, the set value TS _sp of the blown air supply temperature is maintained as it is.

If the set value TS _sp of blown air supply temperature is changed, the air conditioner controller 7 determines the measured value T of the blown air supply temperature.
Output the valve output so that S _pv matches TS _sp ,
The opening degree of the motor-operated valve 2 and the motor-operated valve 4 is controlled.

As described above, in this embodiment, the set value TS _sp of the blow-off air supply temperature becomes energy-saving and satisfies the room temperature based on the cooling / heating status, the direction of change of the return air temperature, and the total control status. The settings will be changed automatically. That is, when the air conditioner 1 continues to output the valve output despite the indoor condition being satisfied or excessive (too cold, too warm), control for weakening the valve output is automatically performed.

Here, in the present embodiment, the direction of change of the return air temperature is used instead of the valve output when determining the outlet air supply temperature, that is, the direction of change of the return air temperature (actual temperature effect). Since the control state of the air conditioner is accurately grasped from the above, the load reset control does not become a disturbance of the air conditioning, the control is stabilized, and the energy loss can be prevented.

In this embodiment, in order to simplify the explanation, the VAV controllers 10-1 to 10-n are used.
Was set as one system, but it may be divided into multiple systems. In this case, the VAV controller master 23 determines the total control status of each system and sends the determined total control status to the air conditioner controller 7. The air conditioner controller 7 determines the set value TS _sp of the blown air supply temperature from the air conditioner 1 in the same manner as described above based on the cooling / heating status, the direction of change of the return air temperature, and the total control status of each system. .

Further, in this embodiment, it is assumed to determine the direction of change of the return air temperature by comparing the first-order lag return air temperature TR _pv 'and return air temperature measurements TR _pv, return air The determination of the direction of temperature change is not limited to this method. For example, remember the return air temperature before a certain time,
The direction of change of the return air temperature may be determined by comparing with the current return air temperature. Alternatively, the direction of change in the return air temperature may be determined by comparing the moving average of the return air temperature (for example, an average of 10 minutes in a 1-minute cycle) with the current return air temperature.

Further, in this embodiment, the return air temperature is used for determining the blow-off supply air temperature, but the return air temperature is not limited. That is, the controlled area 9
Any temperature index may be used as long as it indicates a comprehensive temperature state in -1 to 9-n, and for example, a weighted average of environmental temperatures of the controlled areas 9-1 to 9-n (room temperature PV detected by the temperature sensors T1 to Tn). May be In this case, as a method of determining the direction of change of the weighted average, the same method as in the case of the return air temperature can be considered.

Further, in this embodiment, the VAV controller master 23 is provided and the total control status is obtained by the VAV controller master 23, but the function may be added to the air conditioner controller 7. Further, in this embodiment, the set value TS _sp of the outlet air supply temperature is determined based on the cooling / heating status, the direction of change of the return air temperature, and the total control status. However, in the case of heating only or cooling only Does not require a cooling / heating status.

Further, in this embodiment, the set value TS _sp of the blown air supply temperature in the air conditioner controller 7 can be changed by manual operation. That is,
The set value TS _sp of the air supply temperature from the air conditioner 1 is normally automatically determined by the air conditioner controller 7,
If necessary, manual resetting can be performed using a setting changing means such as a keyboard. As a result, for example, in response to a request from a specific controlled area, the building manager can temporarily change the blown supply air temperature, which provides flexibility. In the past, since there was no such manual reset function, it was impossible to artificially respond to various requests from the controlled area.

[0044]

As is apparent from the above description, according to the present invention, the direction of change of the temperature index indicating the overall temperature state in the first to Nth controlled areas and the first to Nth.
Since the blow-off air supply temperature from the air conditioner is determined based on the total control status obtained from the control status from the variable air supply amount adjusting means, the temperature index of the return air returned to the air conditioner is the temperature index. By using the weighted average of the environmental temperatures in the first to Nth controlled areas or the like, the load reset control is used to accurately grasp the control state of the air conditioner from the direction of change of this temperature index. It is possible to prevent disturbance and to stabilize the control to prevent energy loss. Further, according to the present invention (the second invention), the blow-off air supply temperature from the air conditioner can be manually changed, so that the blow-off air supply temperature from the air conditioner can be manually reset. It is possible to artificially respond to various requests from the control area.

[Brief description of the drawings]

FIG. 1 is an instrumentation diagram of a VAV control system showing an embodiment of the present invention.

FIG. 2 is a diagram showing how control status is determined by a VAV controller.

FIG. 3 is a diagram illustrating the difference in meaning between the control status and the total control status when the cooling / heating status is the cooling mode and the heating mode.

FIG. 4 is a diagram showing how the total control status is determined by the VAV controller master.

FIG. 5 is a diagram showing how the air conditioner controller determines the cooling / heating status.

FIG. 6 is a diagram showing how the air conditioner controller determines the direction of change in the return air temperature.

FIG. 7 is a diagram exemplifying a measurement value of the return air temperature and a change situation of the first-order delayed return air temperature with respect to the measurement value of the return air temperature.

FIG. 8 is a diagram showing the relationship between the total control status, the direction of change of the return air temperature, and the setting change value of the blowout supply air temperature.

[Explanation of symbols]

1 ... Air conditioner, 2, 4 ... Motorized valve, 3 ... Cooling coil, 5 ... Heating coil, 6 ... Blower, 6a ... Fan, 6b ... Inverter, 7 ... Air conditioner controller, 9-1 to 9-n ... Controlled Area, 10-1 to 10-n ... VAV controller, 1
1-1 to 11-n ... VAV unit, 12-1 to 12-
n ... damper, 13-1 to 13-n ... wind speed sensor, 14-
1-14-n ... opening degree sensor, T1-Tn ... temperature sensor,
21, 22 ... Temperature sensor, 23 ... VAV controller master.

Claims (4)

[Claims] 1. A first receiving a supply of blown air from an air conditioner
~ First to Nth variable air supply amount adjusting means for controlling the amount of air supply to the respective controlled areas according to the load condition of the Nth controlled area, and the first to Nth variable air supply amounts While determining the total control status from the control status sent from the adjusting means, the direction of change of the temperature index indicating the overall temperature state in the first to Nth controlled areas is determined, and the determined temperature index is determined. And a blow-off air supply temperature determining means for determining the blow-off air supply temperature from the air conditioner based on the direction of change of the air conditioner and the total control status.
V control system. 2. The VAV control system according to claim 1, wherein the temperature of air supplied from the air conditioner can be changed by manual operation. 3. The VAV control according to claim 1, wherein the temperature index indicating the overall temperature state in the first to Nth controlled areas is the temperature of the return air returned to the air conditioner. system. 4. The temperature index according to claim 1, wherein a temperature index indicating a comprehensive temperature state in the first to Nth controlled areas is first.
~ A VAV control system characterized by being a weighted average of environmental temperatures in the Nth controlled area.