JPH05256100A - Tunnel ventilation controlling system - Google Patents

Abstract

PURPOSE:To make it possible to control stable ventilation fan air-flow. CONSTITUTION:By adding an air-flow decrease ratio operator 9, when fogging permeability or carbon monoxide concentration exceeding reference value once returns to the reference value, air-flow increasing independently is gradually decreased in accordance with decrease ratio calculated by the air-flow decrease ratio operator 9, and it is so controlled that it returns to the initial air-flow designed value in a certain time. According to the controlling system, air-flow of a ventilating fan 2 is not so decreased quickly, and fogging permeability or carbon monoxide concentration exceeds reference value again, so that the air-flow of the ventilating fan 2 is not required to increase again. Therefore, stable ventilating fan air-flow control can be made.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ventilation control system in which ventilation in a tunnel such as an automobile road is forced by a ventilation fan.

[0002]

2. Description of the Related Art In a tunnel, especially in a road tunnel filled with exhaust gas of an automobile, it is necessary to force ventilation by a ventilation fan so that the degree of pollution of air in the tunnel does not exceed a certain standard. In recent years, very long road tunnels have been introduced with a system that automatically controls the forced ventilation by this ventilation fan according to the degree of pollution in the tunnel (for example, "Kanetsu tunnel monitoring control system" Mitsubishi Denki Giho Vol.60, No.7, P.50-
55, 1986).

FIG. 3 is a block diagram of a conventional tunnel ventilation control system.

As shown in the figure, inside the tunnel 1, there is a ventilation fan 2 for forced ventilation, a fume transmittance (VI) meter 3 and a carbon monoxide (CO) concentration meter 4 for measuring the degree of pollution.
A plurality of anemometers 5 and a traffic counter 6 for measuring the traffic volume are installed at predetermined intervals. Further, outside the tunnel 1, there is a ventilation calculator 7 for calculating a planned air flow rate value for each ventilation fan 2 required to keep the VI value and the CO concentration in the tunnel 1 below a preset reference value. , And a plurality of controllers 8 for controlling the air flow rate of each ventilation fan 2 in accordance with the air flow rate planned value calculated by the ventilation calculator 7.

In the tunnel ventilation control system configured as described above, the controller 8 recognizes the air volume of the corresponding ventilation fan 2 and also cycles the measured values of the VI meter 3, the CO concentration meter 4, the anemometer 5, and the traffic counter 6. The ventilation calculation unit 7 reads the measured values thus processed, and calculates the planned air flow rate value for each ventilation fan 2. Then, the controller 8 periodically controls the air volume of the corresponding ventilation fan 2 according to the calculated air volume plan value. As a result, the VI value and C in the tunnel 1
The O concentration and the reference value are maintained.

Further, in this tunnel ventilation control system, even if the air volume of the ventilation fan 2 is controlled in accordance with the air volume plan value, the VI value or the C value can be obtained anywhere in the tunnel 1.
When the O concentration exceeds the reference value, the air volume of the ventilation fan 2 corresponding to the location is increased at a constant rate regardless of the air volume plan value. Then, when the VI value or CO concentration that has exceeded the reference value returns to the reference value, the increased air volume of the ventilation fan 2 is immediately returned to the air volume plan value before the increase.

[0007]

However, as mentioned above,
When the VI value or CO concentration once exceeding the reference value is returned to the reference value again, if the air volume of the ventilation fan 2 is immediately returned to the air volume plan value before the increase, the air volume of the ventilation fan 2 suddenly decreases. As a result, the VI value or the CO concentration may exceed the reference value again. In that case, the air volume of the ventilation fan 2 is also increased.

That is, the conventional tunnel ventilation control system has a problem that the air volume control of the ventilation fan 2 becomes unstable.

The present invention has been made in order to solve this problem, and an object thereof is to obtain a tunnel ventilation control system capable of performing stable ventilation fan air volume control.

[0010]

In order to achieve the above object, in the tunnel ventilation control system according to the present invention, the increased air volume of the ventilation fan is returned to the air volume planned value before the increase regardless of the air volume planned value. At that time, an air volume reduction rate calculator was added to calculate the reduction rate that gradually reduces the air volume of the ventilation fan.

[0011]

According to the tunnel ventilation control system configured as described above, when the fume transmittance or the carbon monoxide concentration once exceeding the reference value returns to the reference value, the air volume increased regardless of the air volume plan value. Can be gradually reduced according to the reduction rate calculated by the air volume reduction rate calculator, and can be controlled to return to the air volume planned value before the increase over a certain period of time.

[0012]

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

FIG. 1 is a block diagram of a tunnel ventilation control system according to the present invention. Incidentally, in FIG. 1, constituent elements that are not different from the conventional example shown in FIG.

As shown in the figure, the difference between this tunnel ventilation control system and the conventional example is that an air volume reduction rate calculator 9 is added.

The air volume decrease rate calculator 9 increases the ventilation regardless of the air volume planned value because the fume permeability (VI) or the carbon monoxide (CO) concentration in the tunnel 1 exceeds the reference value. When the air volume of the fan 2 is returned to the air volume planned value before the increase, the reduction rate for gradually reducing the air volume of the ventilation fan 2 is calculated.

Next, the control operation of the tunnel ventilation control system to which the air volume reduction rate calculator 9 is added will be described with reference to the flowchart of FIG.

First, the controller 8 recognizes the air volume of the corresponding ventilation fan 2, and reads and processes the measured values of the VI meter 3, the CO concentration meter 4, the anemometer 5, and the traffic counter 6 (step S- 1). Subsequently, the controller 8 determines that the processed VI value or CO concentration is
It is determined whether or not it exceeds a preset reference value (S-2). As a result, when the VI value or the CO concentration exceeds the reference value, the controller 8 causes the corresponding ventilation fan 2 to operate regardless of the current ventilation fan airflow plan value.
To increase the air flow rate of the
3), control output (S-4).

As a result of the judgment in step S-2,
If the VI value and CO concentration do not exceed the standard values,
Then, it is determined whether the VI value or the CO concentration has changed so as to exceed the reference value and then return to the reference value (S-5). As a result, when the VI value and the CO concentration do not change as such, the ventilation calculator 7 determines the ventilation fan airflow plan value at this time based on each measured value processed by the controller 8. Calculate (S-6).
However, the calculation of the ventilation fan airflow plan value is invalid if the airflow volume stepwise reduction control described later is in progress. Then, the controller 8 controls and outputs the air volume of the corresponding ventilation fan 2 according to the calculated air volume plan value (S-7).

As a result of the judgment in step S-5,
When the VI value or the CO concentration has once exceeded the reference value and then changed back to the reference value, the air volume of the ventilation fan 2 increased regardless of the air volume plan value is gradually decreased. The air volume decrease rate calculator 9 calculates the decrease rate (S-8). The rate of decrease is calculated by dividing the difference between the current airflow rate of the ventilation fan 2 and the airflow rate planned value to be returned before the increase by the preset airflow rate planned value arrival time (unit: minutes). The time to reach the planned air flow rate should be set appropriately so that stable ventilation fan air flow rate control can be performed, and that it does not become longer than necessary.

Then, the controller 8 controls and outputs the air volume of the corresponding ventilation fan 2 according to the thus calculated reduction rate (S-9).

The air volume of the ventilation fan 2 is controlled by repeating the above steps S-1 to S-9 periodically.

As described above, in this control system, when the VI value or CO concentration once exceeding the reference value returns to the reference value, the increased air volume is reduced regardless of the planned air volume value. The air flow rate is reduced stepwise according to the rate of decrease calculated by the rate calculator 9, and is controlled to return to the air volume plan value before the increase by taking a certain time to reach the planned air volume value. Therefore, as in the conventional example, the air volume of the ventilation fan 2 suddenly decreases, and the VI value or the CO concentration again exceeds the reference value, so that the air volume of the ventilation fan 2 must be increased again. Never. That is, stable ventilation fan air volume control can be performed.

The tunnel ventilation control system according to the present invention can be applied to tunnels other than road tunnels, such as subway tunnels, as long as the ventilation fan is used for forced ventilation.

[0024]

As described above, according to the tunnel ventilation control system of the present invention, when returning the increased air volume of the ventilation fan to the air volume planned value before the increase regardless of the air volume planned value, Since the decrease rate is reduced stepwise according to the decrease rate calculated by the decrease rate calculator, it is possible to perform stable ventilation fan air volume control.

Further, since the air volume of the ventilation fan is not suddenly changed, the load on the ventilation fan can be reduced and its life can be extended.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a tunnel ventilation control system according to the present invention.

FIG. 2 is a flowchart illustrating a control operation of the tunnel ventilation control system according to the present invention.

FIG. 3 is a configuration diagram of a conventional tunnel ventilation control system.

[Explanation of symbols]

 1 Tunnel 2 Ventilation Fan 3 Fume Permeability Meter 4 Carbon Monoxide Concentration Meter 5 Anemometer 6 Traffic Counter 7 Ventilation Calculator 8 Controller 9 Air Volume Reduction Rate Calculator

Claims (1)

[Claims] 1. A ventilation fan for forcedly ventilating the inside of the tunnel, and a measured value of a smoke permeability meter, a carbon monoxide concentration meter, an anemometer, and a traffic counter installed in the tunnel, based on the measured values. Ventilation calculator that calculates the ventilation fan airflow plan value required to keep the smoke permeability and carbon monoxide concentration below the reference value, and the ventilation fan airflow rate according to the airflow plan value calculated by the ventilation calculator. If the smoke permeability or carbon monoxide concentration in the tunnel exceeds the reference value even if the ventilation fan air volume is controlled according to the above air flow plan value, the ventilation fan air volume is adjusted to the above air volume. In a tunnel ventilation control system that increases without depending on the planned value, when returning the air volume of the ventilation fan that has been increased without depending on the planned value of air volume to the planned air volume before the increase, Tunnel ventilation control system, characterized in that the addition of air volume reduction rate calculator for calculating a reduction rate stepwise reduces the air volume of the ventilation fan.