CN102539084A

CN102539084A - Time-of-arrival location principle-based gas leakage point scanner

Info

Publication number: CN102539084A
Application number: CN2012100001185A
Authority: CN
Inventors: 廖平平; 李晶
Original assignee: BEIJING ECOSO TECHNOLOGY DEVELOPMENT Co Ltd
Current assignee: BEIJING ECOSO TECHNOLOGY DEVELOPMENT Co Ltd
Priority date: 2012-01-03
Filing date: 2012-01-03
Publication date: 2012-07-04

Abstract

The invention belongs to the field of compressed air leakage detection, and realizes a time-of-arrival location principle-based gas leakage point scanner of high positioning accuracy. The content of the invention mainly relates to a detector for detecting direction of a gas leakage point by using a time-of-arrival location principle based on there ultrasonic sensors. The gas leakage point detector based on the three ultrasonic sensors provided by the invention is different from the conventional detector using a single ultrasonic sensor; the detector is based on the time-of-arrival location principle; and for a detection part, three ultrasonic sensors are arranged into an equilateral triangle side by side, so that time difference for an ultrasonic signal of the leakage point to reach two of the three ultrasonic sensors is calculated, further the position of the leakage point relative to the center of the equilateral triangle is judged, and direction indication of the leakage point is realized. By using the leakage point detector, the problem of inaccurate direction indication caused by large half power beam width of the conventional detector using single ultrasonic sensor is avoided, and the direction detection accuracy is improved.

Description

A kind of gas leakage point scanner based on time difference positioning principle

Technical field

The invention belongs to pressurized air Leak Detection field, relate to a kind of gas leakage point scanner based on time difference positioning principle.

Background technology

Pressurized air is the serious leakage problem of ubiquity in use, and the pressurized air that leaks in the factory accounts for the 10%-30% of total air consumption usually, causes very big energy dissipation.Leak Detection becomes the energy-conservation important channel of compressed air system.

The principle of the ultrasonic gas leakage detector of existing single-sensor is: compressed-air actuated leakage can produce ultrasound wave; Hyperacoustic propagation has good directivity; When sonac during over against the hyperacoustic direction of propagation of leakage point, the voltage signal amplitude of its output is the highest.In the leakage point testing process, along with sonac towards change, when maximum point appears in its output amplitude, promptly think its towards the place ahead have leakage point.But there is half-power angle in the sonac that is actually used in the gas Leak Detection, i.e. ultrasound wave incident in this angular range, and sensor all can be exported high flat signal, causes the direction location out of true of detector to leakage point.To this situation; The gas leakage point detector that the present invention proposes based on three sonacs; The main time difference positioning principle that adopts is located the leakage point travel direction; The location out of true of having avoided the half-power angle of above-mentioned because sonac to cause more greatly from principle, and easy to use, favourable extensive popularization with industry spot.

Summary of the invention

The object of the inventionBe: provide a kind of based on gas leakage point detector time difference positioning principle, high position precision.

Technical scheme of the present inventionBe:

The present invention adopts three sonacs to receive the ultrasonic signal that leakage point produces jointly, and three sonac sensings are identical, and spatially are arranged in equilateral triangle.Because the distance of leakage point to three sonac has nothing in common with each other, three road ultrasonic signals life period between any two are poor.Through estimation, can obtain the mistiming that the leakage point ultrasonic signal arrives three sensors, and then can obtain the relative position information of leakage point to three sonac.

According to the relative position information of leakage point to three sonac, equilateral triangle and the extended area thereof that sonac constituted is divided into six zones (as shown in Figure 2), can the orientation of leakage point be navigated to wherein certain zone.Suppose that No. three sonac signals are respectively s ₁, s ₂And s ₃, s ₁With respect to s ₂Time-delay be made as dt ₁₂, in like manner, s ₂With respect to s ₃Time-delay be made as dt ₂₃, s ₁With respect to s ₃Time-delay be made as dt ₁₃Dt ₁₂, dt ₂₃And dt ₁₃Estimate to obtain through three road ultrasonic signals being carried out time delay.According to dt ₁₂, dt ₂₃And dt ₁₃The positive negativity of numerical value, can draw the dead ahead that leakage point is positioned at some zones shown in Figure 2.Concrete condition is following:

(1) works as dt ₁₂<0, dt ₂₃<0, dt ₁₃<0 o'clock, leakage point was positioned at dead ahead 1., zone;

(2) work as dt ₁₂<0, dt ₂₃>0, dt ₁₃<0 o'clock, leakage point was positioned at dead ahead 2., zone;

(3) work as dt ₁₂<0, dt ₂₃>0, dt ₁₃>0 o'clock, leakage point was positioned at dead ahead 3., zone;

(4) work as dt ₁₂>0, dt ₂₃>0, dt ₁₃>0 o'clock, leakage point was positioned at dead ahead 4., zone;

(5) work as dt ₁₂>0, dt ₂₃<0, dt ₁₃>0 o'clock, leakage point was positioned at dead ahead 5., zone;

(6) work as dt ₁₂>0, dt ₂₃<0, dt ₁₃<0 o'clock, leakage point was positioned at dead ahead 6., zone;

Arrange and to know by the equilateral triangle of sonac; When the distance of gas leakage point to three sonac equates fully; Leakage point is in the dead ahead of the equilateral triangle that is made up of three sensors, and the line at leakage point and equilateral triangle center and sensor towards parallel.Therefore, after analyzing the orientation of leakage point, but leakage detector rotate a certain angle to the orientation of leakage point so that the dead ahead at the center that is positioned at equilateral triangle of leakage point, that is leakage point is pointed at the center of equilateral triangle.Through said process, realize accurate detection, and have the characteristics that deviation does not increase with the increase that detects distance that detect the leakage point orientation.

Advantage of the present inventionBe: compare with traditional ultrasonic gas leakage detector; The present invention has avoided above-mentioned because the coarse problem in location that the half-power angle of sonac causes more greatly from principle; The orientation detection precision significantly improves, and, detect deviation and do not increase with the increase that detects distance.In addition, it is simple, convenient that the present invention also has use, is easy in advantages such as industry spot popularizations.

Description of drawings

Fig. 1 detector principle schematic

1. sonac 1 (s ₁), 2. sonac 2 (s ₂), 3. sonac 3 (s ₃), 4. leakage point, 5. equilateral triangle center.

Synoptic diagram is sought in Fig. 2 leakage point orientation

1. sonac 1 (s ₁), 2. sonac 2 (s ₂), 3. sonac 3 (s ₃), 5. equilateral triangle center.

Embodiment

Be further described in the face of the present invention down.

The present invention is divided into three parts by the function that realizes: Sensor section, signal processing, interpretation of result and display part.

(1) Sensor section: form by three sonacs, towards identical and be arranged to the equilateral triangle that the length of side is 3 cm with superior performance.Sensor section receives the ultrasonic signal that is sent by leakage point, exports three road voltage analog signals.

(2) signal processing: three road voltage analog signals of Sensor section output convert digital signal to through A/D, are input to digital signal processor (DSP).Because the distance of leakage point to three sonac has nothing in common with each other, life period is poor each other for three road ultrasonic signals that receive.Estimate three road ultrasonic signals mistiming between any two through the time delay algorithm for estimating.It is a lot of to postpone the algorithm for estimating kind, and adopting based on single channel sampled data spline interpolation, with SSD (Sum Square Difference) among the present invention is the time delay algorithm for estimating of evaluation function.This algorithm time delay estimated accuracy is high, and error is less than the sampling period, and computation complexity is less relatively.

(3) interpretation of result and display part: according to the time delay results estimated; Leakage point is navigated to certain regional dead ahead; And judged result shown; And then according to display interface change sonac towards, make the center of the equilateral triangle that three sonacs constitute point to the orientation of leakage point, realize detection to the leakage point orientation.

Claims

1. the gas leakage point scanner based on time difference positioning principle is characterized in that: adopt three to point to identical sonac, be arranged in equilateral triangle; During scanner work, three sonacs receive the ultrasound wave that is sent by leakage point simultaneously, three road ultrasonic signals are carried out the mistiming between any two estimate; To be divided into six zones by the plane at sonac place,, confirm the dead ahead of leakage point, and realize the direction of leakage point is detected in a certain zone to 3 groups of mistiming data analyses.

2. according to claim 1 a kind of based on gas leakage point scanner based on time difference positioning principle; It is characterized in that: the plane at sonac place is divided into six zones; These six zones are divided by three straight lines; Three straight lines a bit are the points at each sonac place respectively through 2 points, on the other hand the central point of the equilateral triangle of sonac composition.