JPH0762998A - Automatic ventilation control device - Google Patents

Abstract

PURPOSE:To improve the reliability of control by A/D-converting the signal from an exhaust gas transmissionmeter of a tunnel into the time series data, calculating the linearized measured value with the set coefficient, and performing the ventilation control with this value. CONSTITUTION:The exhaust gas transmission factor or the like is estimated from measured values of a CO meter (carbon monoxide concentration), a WS meter (wind direction and wind velocity), and a TC meter (traffic quantity) installed in a road tunnel and the present operation quantity of a ventilation device, and the operation quantity of the ventilation device is controlled based on the estimated value. The measured signal from a VI meter (exhaust gas transmission factor and quality of visibility) 11 is A/D-converted 13 into the time series data, and the linearized measured value TAU1 is calculated by the equation TAU1=A(B-log10(TAU0)) with the data TAU0 and set coefficients A, B. The estimation of the exhaust gas transmission factor and the operation control 15 of the ventilation device are performed with this TAU1. Calculation is easily made, and the reliability of operation control can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic ventilation controller for automatically controlling a ventilator so that a pollution concentration in a road tunnel does not exceed an allowable value, and more particularly to an input processing device for a VI (smoke permeability) meter. .

[0002]

2. Description of the Related Art FIG. 3 is a block diagram of a conventional automatic ventilation control system for a road tunnel. The prediction unit 1 includes a VI meter (soot transmittance, good visibility) 2 that is a sensor installed inside and outside the tunnel, a CO meter (carbon monoxide concentration) 3, and a WS.
The current measured values are taken in from the meter (wind anemometer) 4 and the TC meter (traffic counter, traffic meter) 5, etc., and the NJF (current ventilation operation amount) is also taken in to predict the soot and smoke permeability VIf and A carbon oxide concentration predicted value COf is obtained.

Of these predictions, the measured value of the VI meter is used to predict contamination from the rate of change and to determine the unsteady state from the upper and lower limits.

The control output determining unit 6 calculates increase / decrease of the operating amount of the ventilator from the predicted value derived by the predicting unit 1,
Get control output.

With this ventilation automatic control device, the concentration of pollution caused by exhaust gas and soot in the road tunnel is reduced.

[0006]

In the conventional ventilation automatic control device, various data are used for predicting the pollution state of the tunnel. Among them, the value of the VI meter is important as data showing the amount of pollution itself, but has the following characteristics.

(1) The output τ (%) is related by the following equation with respect to the soot concentration K and the soot layer thickness L: τ = 100 * 10 ^{−KL The} measured value is basically proportional to the degree of real contamination. Not a relationship (linear).

(2) The VI meter is generally of a floodlight type and is automatically calibrated when the sensitivity is lowered due to dirt or the like.
At this time, the offset and the gain may change. In this case, the VI value τ ₁ before calibration and the VI value τ ₂ after calibration have the following relationship.

Τ ₁ = 100 * 10 ^-KL τ ₂ = a * 100 * 10 ^-KL + b where a: gain appearing after calibration b: offset appearing after calibration From the above relationship, the measured value of the VI meter In the automatic ventilation control using, it was necessary to handle the measured values in consideration of the non-linear characteristic and the calibration, which made the equipment design and operation management difficult.

An object of the present invention is to provide a ventilation automatic control device which facilitates the handling of the measured value of a VI meter.

[0011]

In order to solve the above-mentioned problems, the present invention predicts the soot smoke transmission rate and the like from each measured value of the road tunnel obtained from the soot smoke transmission rate meter and the like and the current ventilation operation amount, In an automatic ventilation control device for increasing / decreasing the operating amount of a ventilator according to this predicted value, an A / D converter for converting a measurement signal from the soot and smoke transmittance meter into time series data, and a measurement value to be the time series data Using τ ₀ and the setting coefficients A and B, a linearization processing unit that obtains a measured value τ _L that is linearized by the calculation of the following equation τ _L = A (B−log ₁₀ (τ ₀ )), and this linearization It is characterized by being provided with a control unit for predicting soot and smoke and using the measured value τ _L for ventilation control.

[0012]

[Function] The measurement value from the soot smoke permeability meter is converted into a digital value by the A / D converter, and the digital value is linearized by the linearization processing unit, and the control unit uses the linearized data to control ventilation. Various predictive control and ventilation control for are performed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a soot transmittance measuring process showing an embodiment of the present invention. The measurement signal from the VI meter 11 is taken into the main body of the control device via the interface 12, and this signal is converted into a time series digital value by the A / D converter 13.

The linearization processing unit 14 linearizes the digital value input τ ₀ from the A / D converter 13 according to the following equation.

Τ _L = A (B−log ₁₀ (τ ₀ )) (1) This calculation means the calculation of the following equation from the non-linear characteristic of the VI meter 11.

Τ _L = A (B− (log ₁₀ 100 + log ₁₀ 10 ^−KL )) = A (B−2 + KL) (2) That is, the calculation result by the linearization processing unit 14 is
The measurement value of the non-linear characteristic of the VI meter 11 is linearized, which makes it unnecessary to consider the non-linearity of the measurement value in the calculation on the control unit 15 side.

In addition to this, adjustment of the coefficient B for the offset and the coefficient A for the gain is facilitated. These coefficients A,
The determination of B is made by the following procedure.

(1) When the number of vehicles running in the tunnel is small and the ventilation is sufficient, V at that time is
By setting 'from B = log ₁₀ (τ _0' measurement signal I meter tau _{0 as) ...... (3), τ L} = A · K · L subsequent measurements tau _L at that time as a reference without contamination ...... (4) can be calculated and offset can be processed.

(2) The coefficient A can be determined so that when the number of vehicles in the tunnel is the maximum, KL (theoretical value) can be obtained from the number of vehicles and the mixing rate.

FIG. 2 shows a processing flowchart of the linearization processing section 14. The time series data of the measured value of the VI meter is read (step S1), and then it is determined whether or not the coefficient has been changed (step S2).

When the coefficient is not changed, the second term in the parentheses of the above equation (1) is calculated for the measured value (step S
3) Then, using the known coefficients A and B, the operation of the equation (1) is performed to obtain the linearized measured value τ _L (step S4).

When the coefficient is changed in step S2, the coefficient B is obtained by the calculation according to the above equation (3) (step S2).
5) Then, the coefficient A is obtained by the calculation according to the equation (4) (step S6), and the process returns to the calculation of the measured value τ _L.

[0023]

As described above, according to the present invention, the measurement signal from the soot transmittance meter is converted into time series data, and this data is linearized to be used for calculation for soot transmittance prediction and ventilation control. Since it is used, it has the following effects.

(1) The measurement signal of the VI meter can be made proportional to the soot transmission rate, which facilitates the calculation for soot transmission rate prediction and ventilation rate control.

(2) To facilitate the adjustment of the offset amount and the gain.

(3) The rate of change of the VI measurement value and the calculation of the upper and lower limits coincide with the original physical quantity, and the reliability of the control side can be improved in the prediction of contamination.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart of linearization processing in the embodiment.

FIG. 3 is a block diagram of a ventilation control device.

[Explanation of symbols]

 11 ... VI meter 12 ... Interface 13 ... A / D converter 14 ... Linearization processing unit 15 ... Control unit

Claims (1)

[Claims] 1. Automatic ventilation control for predicting the soot transmission rate and the like from each measured value of a road tunnel obtained from a soot transmission rate meter and the like and the current ventilation operation amount, and increasing / decreasing the operation amount of the ventilation according to the estimated value. In the apparatus, an A / D converter that converts the measurement signal from the soot and smoke transmittance meter into time series data, and a measurement value τ that becomes the time series data.
A linearization processing unit for obtaining a linearized measurement value τ _L by the calculation of the following equation τ _L = A (B−log ₁₀ (τ ₀ )) using ₀ and the setting coefficients A and B, and the linearized measurement An automatic ventilation control device comprising a control unit for predicting soot and smoke and controlling ventilation using the value τ _L.