JPS6020039A - Variable air quantity system in air conditioner - Google Patents

Abstract

PURPOSE:To completely balance the air quantities of feed air and exhaust air systems and to stabilize the indoor pressure and to save energy by using the static pressure control of a blower using a static pressure sensor in combination with the air quantity control of the blower using a feed air speed sensor and an exhaust air speed sensor. CONSTITUTION:A feed air speed sensor VS for detecting the feed air passing quantity and an exhaust air speed sensor VR for detecting the exhaust air passing quantity are provided at sufficiently current form-shaped positions of a feed air system and an exhaust air system, and a static pressure sensor 7 is disposed at the terminal end of a feed air duct 3 of the feed air system. On the other hand, a feed air quantity control signal for controlling the rotational speed of a blower 5 is supplied to the blower 5 so as to make constant the static pressure within the duct 3 by the detection signal from the sensor 7, and detection signals from respective air speed sensors are compared with each other, and an exhaust air quantity control signal for controlling the rotational speed of a blower 6 so that respective passing air quantities assume values within the range of preset values, is supplied to the blower 6. As a result, the air quantities of the feed air system and the exhaust air system can be completely balanced, and the indoor pressure can be stabilized and energy can be saved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to improvements in variable air volume systems in air conditioning.

(Prior Art) Conventionally, as shown in FIG. 1, in an air conditioning system, a plurality of rooms 1. . . . , 1. Indoor thermostat 2. . . . 2 makes the air duct 3. ..., 3, the opening/closing control signal is sent to the variable air volume machines (V A V ) 4,..., 4, and the variable air volume machines 4. 4 opens and closes and the air volume fluctuates, and in order to keep the static pressure inside the duct constant, which fluctuates accordingly, air is blown (in 5, the air duct 3 at the end
A supply air volume control signal is sent from the static pressure sensor 7 in the inverter 6 via the regulator 8, an exhaust air volume control signal is sent from the dynamic pressure sensor 19 to the exhaust fan 6 via the regulator 20, and the inverter 9. Tenkawa is a variable scenery system in which the rotation speed of the blower 5 and the reconnaissance rock 6 is controlled via the io to adjust the amount of air blown and the amount of air discharged. In addition, 11 is an air conditioner including a blower with a 5° morning breeze (12 is a heating coil, 13 is a cooling filter, 14, 15 is a filter, 16 is an adjustment damper, 17 is an outside air intake damper, 1) 3 is a bleed damper.

By the way, in the conventional variable air volume system described in Section 1, air blowing is performed by using a combination of static pressure sensor 7 and dynamic pressure sensor 19. It is difficult to balance the supply and exhaust volumes, and when the supply and exhaust volumes are unbalanced, the indoor pressure will fluctuate.If the indoor pressure becomes negative, outside air will enter, and vice versa. When the indoor pressure becomes high, indoor air flows out, and in either case, the problem of increased heat load is unavoidable.Also,
For buildings that do not like sudden pressure fluctuations indoors, supplementary (RJI)
A separate control device is required.

(Objective of the Invention) The basic object of the present invention is to completely balance the air volume of the air supply and exhaust system to stabilize indoor pressure and to save energy.

(Structure of the Invention) For this reason, the present invention provides an air supply air velocity sensor that detects the amount of air passing through the supply air and an exhaust air speed sensor that detects the amount of air that passes through the exhaust air, which are installed at sufficiently rectified positions in the air supply system and the exhaust system, respectively. In addition to providing each wind speed sensor, a static pressure sensor is provided at the end of the air supply duct of the air supply system.The air supply system uses a detection signal from the static pressure sensor to control the rotation speed to keep the static pressure in the duct constant. An exhaust air volume that sends an air volume control signal to one air blower and compares the detection signals from each wind speed sensor to control the rotation speed so that each passing air volume falls within a preset set value range. It is configured to send a control signal to the exhaust fan.

The rotational speed of the air blower is controlled using the detection signal of the static pressure inside the duct by the static pressure sensor, and the amount of air passing through the supply air by the supply air speed sensor and the amount of air passing through the supply air by the exhaust air speed sensor are the same type. Static pressure and air volume control, which controls the rotational speed of the exhaust fan by comparing detection signals with a microcomputer, allows the air volume of the air supply and exhaust system to be more perfectly balanced.

(Effects of the Invention) According to the present invention, since the air blowing (static pressure control) using the static pressure sensor and the air volume control of the exhaust fan using the supply air and exhaust air speed sensors are used together, the layer pressure control is effective. This problem is canceled by air volume control, and responsiveness and control accuracy are greatly improved, making it possible to perfectly balance the supply and exhaust volume.

(Example) Components having the same structure and function as those of the prior art shown in FIG.

In FIG. 2, the supply air speed sensor VS and the exhaust air speed sensor VR are placed in the air conditioner 11 at a position where the air supply and morning air of the air supply system and air system are sufficiently rectified.

Supply air wind speed sensor of the supply air system＼・"S is filter 14
Since the air flow is most rectified downstream of
It is preferable to subtract 1.

It is preferable to install the bleed air velocity sensor VR of the 11 air system at a position downstream of the filter 15, since the wind is most rectified downstream of the filter 15.

A static pressure sensor 7 is provided at the end of the air supply duct 3 of the air supply system.

Each wind speed sensor ■s, ~゛R is a microcomputer 2
2, each wind speed sensor V3. After the VR detection signal is processed by the microcomputer 22, it is applied as an exhaust air volume control signal to the inverter 1 ( ) of the grab wind shore 6,
The rotation speed is controlled and the exhaust air volume changes.

The microcomputer 22 is configured like a person after the air conditioner 11 is installed on site (see FIG. 3).

(Setting O) Input the relationship between the control voltage E of the inverter 10 and the output frequency I.

(Setting 1) Input the passage cross-sectional area KS, KR at the setting position of each wind speed sensor \・”S, ■R.

(Setting 2) Set a lower limit value Yll and a lower limit value Y2 of the supply/exhaust air volume ratio. (The actual supply/exhaust air volume ratio is controlled between these set values.) YllY2'' Exhaust air volume/supply air volume The microcomputer 22 above controls the exhaust fan 6 as follows (see Figure 3). .

(1) Input the wind speed V from the wind speed sensor VS.

(2) Calculate the supply air volume QS from the wind speed value v3 (Qs=
Ks-v,).

On the other hand, based on the detection signal from the static pressure sensor 7, the controller 8 controls the rotational speed of the air blower to keep the static pressure inside the duct constant.

(:() Input the wind speed V from the wind speed sensor VR.

(4) Calculate the wind power Q'R from the wind speed value ν.

(QR=KR-vr) (5) Output the supply 4J + air volume ratio X (X=Ql</
QS).

(6) Compare the current air volume value X and the set value YllY2 ('2≦X≦Y).

(G-1) If the current air volume ratio exceeds the set value (X
>'l'l), increase the inverter control voltage of JiJl wind beach 6 by 1 to lower the frequency on the 71 air side and reduce the number of air grabs.

(6-2) When the current air volume ratio is less than the set value (X<)
', ), 11 Increase the inverter control voltage of the wind iso 6 to increase the exhaust side frequency and increase the exhaust air volume.

That is, in response to load fluctuations in the room 1, the indoor thermostat 2 sends an opening/closing control signal to the variable air volume machines 4 at the ends of the ventilation duct 3, 4 and 11. In order to minimize the amount of air in the duct that changes accordingly, the air supply amount Qs of the blower 5 is controlled by the detection signal from the static pressure sensor 7.

For example, as shown in Figure 14, the first point 1: Qsl.

SL) moves to point 2 (QS2.S2) by throttling the variable air volume device 4, the static pressure sensor 7 detects the static pressure S2, and then the controller 8. The inverter 9 controls the blower 5 to operate at three points.

Next, the wind speed sensor VR 411 detects the wind speed Vrf corresponding to the exhaust air volume Q1< of the exhaust fan 6! : The signal is compared with the signal detected by the supply air speed sensor in the microcomputer 22, and the rotation speed is set to the exhaust fan 6 so that each amount of passing air falls within a preset value range. A control signal is sent to control the

For example, as shown in FIG. 5, when the air blower 5 changes from the air volume QSI to QS2 due to the variable air volume (throttle of the fan 4), the exhaust air volume is the air volume QR1 before the throttle of the variable air volume fan 4. The exhaust air volume ratio X is X”QR1/QSI,
The air volume is equal to or higher than the set value (X>Yl), and the air supply (1) becomes unbalanced.

Therefore, the microcomputer 22 sends a control signal to the inverter 10 of 6 to control the rotation speed so that the supply/exhaust air volume ratio X falls within the upper and lower limits of the air volume ratio setting value. Decrease the amount of exhaust air from the rocky shore 6.

In addition, the example in -1- is when the variable air volume fan is closed; on the other hand, when it is opened, its operation is first controlled by the air blower 5 based on the detection of the static pressure sensor 7, as shown in the flow shown in Figure 3. In response to the control amount, the air pressure control 6 is controlled to balance the air supply and exhaust amount.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of a conventional variable air volume system, Fig. 2 is an explanatory diagram of a variable scenery system according to the present invention, Fig. 3 is a control flowchart by a computer, and Fig. 4 is a graph showing static pressure control of a blower. FIG. 5 is a graph showing the air volume control of the exhaust fan. 1...Indoor, 2...Indoor thermostat, 3...Blower duct, 4...Variable air volume machine, 5...Blower, 6...
・Exhaust fan, 7... Static pressure sensor, 9, 10... Inverter, 1
1...Air conditioner, 2'2...Microcomputer, \is...Inlet air speed sensor, \7R...Exhaust air speed sensor.

Claims (1)

[Claims] (1) In response to indoor load fluctuations, the indoor thermostat sends an opening/closing control signal to the variable air volume machine at the end of the duct, and this uJ variable air volume rock opens and closes, causing the air volume to fluctuate, and the static pressure inside the duct to fluctuate accordingly. This is a variable air volume system, in which a landscape control signal is sent to the 11 fans to control the air blower and the air grabber in order to keep the amount of air constant. A supply air speed sensor that detects the amount of air passing through the supply air and an exhaust air speed sensor that detects the amount of air that passes through the supply air system are installed at sufficiently rectified positions in the air system and the exhaust system. end of air duct)°1b to 11i
An I pressure sensor is provided, and a detection signal from the static pressure sensor is used to send a supply air volume control signal to the air flow rate to control the number of times in order to keep the static pressure in the duct constant. A variable air conditioning system characterized in that the detection signals are compared and an exhaust air volume control signal is sent to the exhaust fan to control the rotation speed so that each passing air volume falls within a preset set value range. Air volume system.