JPH0359344B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an air handling unit used for air conditioning in buildings and the like.

Conventional configurations and their problems Air handling units have traditionally been used for air conditioning in buildings, etc., but in recent years, control methods have become more sophisticated with the aim of improving comfort in air conditioning and reducing operating power. I've done it.

Hereinafter, the conventional air handling unit as described above will be explained with reference to the drawings.

In FIG. 3, 1 is an air handling unit housing, 2 is a blower built into the air handling unit housing 1, 3 is a heat exchanger, 4 is a filter, and 5 is a damper. Reference numeral 6 indicates a supply air duct, 7 indicates an air-conditioned room, and 8 indicates a return air duct, which are connected to the air handling unit housing 1 to form a serial wind path. Reference numeral 9 denotes a temperature detector installed inside the air-conditioned room 7, and is electrically connected to the temperature detection section 11 of the control device 10. The control device 10 further includes a temperature setting section 12 and a temperature detection section 1.
1, a comparison section 13 that compares the signal from the temperature setting section 12, a valve opening/closing command section 14 that calculates and amplifies the signal from the comparison section 13, and a start/stop command section 15 that commands the blower 2 to start or stop. , and a control constant setting section 18. 16 is a valve that controls the amount of water flowing through the heat exchanger 3;
Reference numeral 17 denotes a valve driving device that drives the valve 16 to open and close. The valve opening/closing command section 14 and the valve driving device 17, and the start/stop command section 15 and the blower 2 are electrically connected, respectively.

The control constant setting section 18 consists of a group of switches,
The ON/OFF combination of the switch group is transmitted to the valve opening/closing command unit 14 as a digital setting value.

In the above configuration, the wind generated by the blower 2 returns to the air handling unit housing 1 via the supply air duct 6, the air conditioned room 7, and the return air duct 8, and then passes through the filter 4 and the heat exchanger 3. The air is sucked into the blower 2 through the air. The damper 5 adjusts the exhaust amount and intake amount by adjusting its rotation angle. On the other hand, the signal obtained by the temperature detector 9 is transmitted to the control device 10.
input to the temperature detection section 11 of.

Next, the operation and effect of the control device 10 will be explained.

FIG. 4 is a signal waveform diagram of the control device 10 of a conventional air handling unit. The signal waveform diagram in FIG. 4 shows the state when cold water is flowing through the valve 16 and the heat exchanger 3, that is, during cooling operation.

In FIG. 4, T ₀ , T _{1 .} . . are detection timings, and the opening/closing direction and opening/closing operation time of the valve from that time are determined depending on the magnitude relationship between the detected temperature and the set temperature at that time. Now, at T ₀ , the valve opening command starts, and the valve opening gradually increases until it becomes fully open. This state continues until time T _1. At T ₁ , the detected temperature has decreased, so the valve is not opened as much as at T ₀ . There is no need to open it, and the valve close command will begin this time. Along with this, the valve opening degree gradually decreases and maintains a constant opening degree together with the valve closing command, and continues until the time of this state _T2 . Thereafter, the same detection, command, and operation are repeated. The opening/closing operation time is calculated by the valve opening/closing command unit 14 in FIG. 3, and the digital setting values received from the control constant setting unit 18 are used as various constants for the calculation. Note that the set values include the calculation interval, proportional gain, integral time, differential time, and the like.

However, in the above method, the control constant settings are input manually, so it is difficult to control the calculation interval, proportional gain, integral time, derivative time, etc., especially in the trial run stage of automatic operation control of the air handling unit. We were forced to determine each constant separately through trial and error.
Problems include that the test run adjustment takes a long time, and that the adjustment results need to be readjusted due to changes in the season, the amount of heat dissipated from indoor equipment, etc.

OBJECTS OF THE INVENTION In view of the above-mentioned problems, the present invention provides an air handling unit that automatically determines control constants, reduces the number of adjustment steps, and keeps the control constants appropriate at all times.

Structure of the Invention To achieve this object, the air handling unit of the present invention includes a temperature detector, a valve, a valve driving device connected to the valve, and a target value set using a signal from the temperature detector as a detected temperature. The control device includes a control device that receives an input as a set temperature and a check timing input as a check timing, and outputs it as a valve opening/closing command to the valve driving device, and the control device inputs the input as a check timing to the valve driving device each time the check timing is input. means for giving a fully closed signal for a predetermined time and then a fully open signal for a predetermined time;
It is configured to include means for detecting the rate of change in the detected temperature while the fully open signal is being applied, and for calculating a control constant in accordance with the rate of change.

With this configuration, the control constants can be automatically determined, the number of adjustment steps can be reduced, and the control constants can always be maintained at an appropriate level, thereby achieving the objective.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a piping and wiring system diagram of an air handling unit in one embodiment of the present invention. In the figure, the constituent elements numbered 1 to 9 are the same as those of the conventional example explained in FIG. 1, and the explanation thereof will be omitted. The temperature detector 9 is electrically connected to the temperature detection section 21 of the control device 20. The control device 20 further includes a temperature setting section 22, a comparison section 23 that compares the signal of the temperature detection section 21 and the signal of the temperature setting section 22, and a valve opening/closing command section 24 that calculates and amplifies the signal of the comparison section 23.
and a start/stop command unit 25 that commands the blower 2 to start and stop. 16 is a valve that controls the amount of water flowing through the heat exchanger 3, and 17 is a valve drive device that opens and closes the valve 16. Valve opening/closing command section 24 and valve drive device 17,
The start/stop command section 25 and the blower 2 are electrically connected to each other.

Reference numeral 26 denotes a check timing generating section, which generates a check timing pulse at a fixed time once a day. When the valve opening/closing command unit 24 receives the check timing pulse, it gives a full close signal to the valve driving device 17, and then gives a full open signal. As a result, the room temperature suddenly changes.

FIG. 2 is a signal waveform diagram.

Note that the signal waveforms in FIG. 2 are for the valve 16 and the heat exchanger 3.
This shows the situation when cold water is flowing through the air conditioner, that is, during cooling operation.

In FIG. 2, T ₀ , T _{1 .} . . are detection timings, and the valve opening/closing command time from that time is determined based on the magnitude relationship between the detected temperature and the set temperature at that time. When the valve opening command starts at T ₀ , the valve opening degree gradually increases until it reaches 100%, and this state continues until time T ₁ . At T ₁ , the detected temperature has decreased, so there is no need to open the valve as much as at T ₀ , and the valve closing command starts from now on. Along with this, the valve opening degree gradually decreases, and when the valve closing command is discontinued, the constant opening degree is maintained, and this state continues until time _T2 . At _T2 , a check timing input is input, and the valve closing command continues until _T3 , and the valve opening eventually becomes 0%. Continuing on, the valve opening command starts at T ₃ ,
Valve opening increases from 0% to 100%. During this period, the detected temperature decreases exponentially. The valve opening/closing command unit 24 of the control device 20 in FIG. 1 calculates control constants such as the calculation interval after the next detection timing, the proportional gain, the integral time, and the differential time from the falling rate of the detected temperature. Furthermore, if we use microcomputers that have developed in recent years, the above calculation can be done as follows.
It can be performed at high speed and with high precision.

Effects of the Invention As described above, according to the present invention, a temperature detector;
A signal from a valve, a valve driving device connected to the valve, and the temperature detector is inputted as a detected temperature, a target value setting input is inputted as a set temperature, and a check timing input is inputted as a check timing, and the signals are inputted to the valve driving device. It has a control device that outputs a valve opening/closing command, and the control device includes means for giving a full close signal for a predetermined time to the valve drive device and a full open signal for a predetermined time every time the check timing is input, It is equipped with a means for detecting the rate of change in the detected temperature during the application, and a means for calculating a control constant according to the rate of change. Constants can be determined automatically, the number of adjustments can be reduced, and the control constant can always be kept appropriate.

[Brief explanation of drawings]

Fig. 1 is a piping and wiring system diagram of an air handling unit according to an embodiment of the present invention, Fig. 2 is a signal waveform diagram of the same, Fig. 3 is a piping and wiring system diagram of a conventional air handling unit, and Fig. 4 is a diagram of the same signal. FIG. 9...Temperature detector, 16...Valve drive device, 17
... Valve, 20 ... Control device.

Claims (1)

[Claims] 1 A temperature sensor, a valve, a valve driving device connected to the valve, and a signal from the temperature sensor as the detected temperature, a target value setting input as the set temperature, and a check timing input as the check timing. The control device includes a control device that outputs a valve opening/closing command to the valve drive device, and the control device gives a full close signal for a predetermined time and a full open signal for a predetermined time to the valve drive device every time the check timing is input. and means for detecting the rate of change in the detected temperature while giving the fully open signal;
An air handling unit comprising means for calculating a control constant according to the rate of change.