CN101793548A - Device and method for coherent separation of noise of equipment of direct-current convertor station - Google Patents

Abstract

The invention discloses a device and method for coherent separation of equipment noise in a DC converter station. A sound transmission device and a laser vibrometer are respectively arranged outside the tested equipment, and the sound transmission device and the laser vibrometer are respectively measured by the sound transmission device and the laser vibrometer. The noise signal and vibration signal of the measuring equipment are analyzed by the computer, that is, the noise at the frequency with a large coherence value is generated by the device when the coherence value is small (for example, at a given confidence Noise at frequencies less than 0.8 degrees) is not caused by vibration of the device under test. The invention does not need to be in contact with the equipment under test, can measure the vibration and noise of the equipment under test at a long distance, avoids the danger of high voltage, and ensures the safety of the instrument; The place where the equipment radiates noise together separates the noise spectrum and noise value of a certain equipment.

Description

Device and method for coherent separation of equipment noise in DC converter station

technical field

The present invention relates to the technical field of noise coherent separation, in particular to a device and method for noise coherent separation of DC converter station equipment.

Background technique

The HVDC converter station (hereinafter referred to as the converter station) is a place with high noise pollution. Controlling the noise of each equipment in the converter station is the main measure to prevent and control noise pollution. When controlling equipment noise, it is necessary to know the size and characteristics of the noise radiation of each equipment, which requires accurate measurement of the noise radiated individually by each equipment.

There are many different types of equipment in the converter station. Even if it is the same type of equipment, there are many equipments running at the same time, which makes the noise in the HVDC converter station overlap and interfere with each other. The noise measured at any point is their superposition value, and the sound field in the converter station is very complex. At present, in order to measure the noise of each equipment in the converter station, a sound level meter is used for simple measurement near each equipment. Since each device has high voltage, it is not allowed to be close to the measurement, and when it is far away from the device, it is extremely susceptible to interference from the operating noise of other devices.

Therefore, it is very difficult to accurately measure the noise of a certain equipment in the converter station.

Contents of the invention

The technical problem to be solved by the present invention is to provide a device and method for coherent separation of equipment noise in a DC converter station, which uses the coherence between vibration and noise to separate a certain Noise spectrum and noise magnitude of the equipment.

In order to solve the above problems, the technical solution of the present invention is:

A coherent separation device for equipment noise of a DC converter station, characterized in that it includes a device under test for the noise of a DC converter station, and a directional sound transmission device and a laser vibrometer pointing to the device under test are arranged in front of the device under test Anti-aliasing filter, data collector and computer are also respectively arranged outside the tested equipment, and the output end of described sound transmission device and laser vibrometer is connected in series with anti-aliasing filter, data collector and computer successively by wire .

The noise coherent separation device for DC converter station equipment is characterized in that the sound transmission device includes a cup-shaped sound cover, one end of the cup-shaped sound cover is a large-diameter open end, and the other end is a small-diameter closed end The shell of the cup-shaped sound cover is a metal body with good sound insulation performance, and a layer of sound-absorbing material is laid close to the inner wall of the cup-shaped sound cover and its small-diameter closed end; an amplifier is installed along the inner axis of the cup-shaped sound cover. One end of the amplifier is fixedly connected with a microphone, and the receiving surface of the microphone faces the large-diameter opening end of the cup-shaped sound cover, and the other end of the amplifier is embedded in the sound-absorbing material and connected with lead wires.

A method for coherent separation of equipment noise in a DC converter station, characterized in that it includes the following steps:

(1) Set up a directional sound transmission device and a laser vibrometer at intervals outside the noise-tested equipment of the DC converter station, and at the same time make the receiving end of the directional sound transmission device and the laser vibrometer emit The laser points to the DC converter station equipment under test;

(2) The noise signal emitted by the device under test obtained by the directional sound transmission device and the vibration signal on the surface of the device under test measured by the laser vibrometer are respectively filtered and converted into digital signals and sent to the computer for further processing. Spectrum calculation and coherent analysis;

(3) The computer calculates the coherence function value (ie, coherent spectrum) of the noise signal and vibration signal transmitted from the same device under test, compares the noise spectrum and coherent spectrum of the same device under test, and draws the conclusion of the noise source by comparison : The noise at a frequency with a large coherence value is the noise generated by the surface vibration of the device, and the noise at a frequency with a small coherence value (for example, less than 0.8 at a given confidence level) is not caused by the vibration of the device under test In other words, the noise at the frequency with a large coherence value is generated by the device under test, otherwise the noise at this frequency is not generated by the device under test.

Beneficial effects of the present invention:

The invention does not need to be in contact with the equipment under test, can measure the vibration and noise of the equipment under test at a long distance, avoids the danger of high voltage, and ensures the safety of the instrument; The place where the equipment radiates noise together separates the noise spectrum and noise value of a certain equipment.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the device of the present invention, and the arrows in the figure indicate the direction of the signal.

Fig. 2 is a structural schematic diagram of the sound transmission device of the present invention.

Detailed ways

Referring to Figures 1 and 2, a noise coherent separation device for DC converter station equipment includes a device under test 1, and a directional sound transmission device 2 and a laser vibrometer 3 are respectively arranged outside the device under test 1. The device 2 includes a cup-shaped sound cover 4, one end of the cup-shaped sound cover 4 is a large-diameter open end, and the other end is a small-diameter closed end; the shell of the cup-shaped sound cover 4 is a metal body with good sound insulation performance, which is close to the cup. A layer of sound-absorbing material 5 is laid on the inner wall of the shape-shaped sound cover 4 and its small-caliber closed end; an amplifier 7 is installed along the inner axis of the cup-shaped sound cover 4, and one end of the amplifier 7 is fixedly connected to a microphone 8, and the receiving surface of the microphone 8 Facing the large-diameter opening end of the cup-shaped acoustic mask 4, the other end of the amplifier 7 is buried in the sound-absorbing material 5 and connected with a lead wire 6; the device under test 1 is also provided with an anti-aliasing filter 9 and a data collector 10 respectively. and the computer 11, the output terminals of the acoustic transmission device 2 and the laser vibrometer 3 are sequentially connected in series with an anti-aliasing filter 9, a data collector 10 and a computer 11 through wires.

A method for coherent separation of equipment noise in a DC converter station, comprising the following steps:

(1) Set a directional sound transmission device and a laser vibrometer at intervals outside the device under test, and at the same time make the large-diameter opening end of the directional sound transmission device and the laser pointing emitted by the laser vibrometer Tested DC converter station equipment;

(2) The noise signal emitted by the device under test obtained by the directional sound transmission device and the vibration signal on the surface of the device under test measured by the laser vibrometer are respectively filtered and converted into digital signals and sent to the computer for further processing. Spectrum calculation and coherent analysis;

(3) The computer calculates the coherence function value (ie, coherent spectrum) of the noise signal and vibration signal transmitted from the same device under test, compares the noise spectrum and coherent spectrum of the same device under test, and draws the conclusion of the noise source by comparison : The noise at a frequency with a large coherence value is the noise generated by the surface vibration of the device, and the noise at a frequency with a small coherence value (for example, less than 0.8 at a given confidence level) is not caused by the vibration of the device under test In other words, the noise at the frequency with a large coherence value is generated by the device under test, otherwise the noise at this frequency is not generated by the device under test.

Claims (3)

1. noise of equipment of direct-current convertor station phase dry separation device is characterized in that: include DC converter station noise equipment under test, described equipment under test the place ahead is provided with directive property sound-conducting apparatus and the laser vibration measurer that points to equipment under test; Equipment under test also is respectively arranged with anti alias filter, data acquisition unit and computing machine outward, and the output terminal of described sound-conducting apparatus and laser vibration measurer is connected in series anti alias filter, data acquisition unit and computing machine successively by lead.

2. noise of equipment of direct-current convertor station phase dry separation device according to claim 1 is characterized in that described sound-conducting apparatus includes cup-shaped acoustic shell, and an end of described cup-shaped acoustic shell is bigbore openend, and the other end is small-bore closed end; The shell of cup-shaped acoustic shell is a sound insulation value preferred metal body, and inwall and its small-bore closed end that gets of being close to cup-shaped acoustic shell are equipped with one deck acoustic absorbant; The place is equipped with amplifier along cup-shaped acoustic shell axis line inside, and an end of amplifier is fixedly connected with microphone, and the receiving plane of microphone is towards the heavy caliber openend of cup-shaped acoustic shell, and the other end of amplifier is imbedded in the acoustic absorbant and is connected to the lead of drawing.

3. the relevant separation method of a noise of equipment of direct-current convertor station is characterized in that: may further comprise the steps:

(1), spacing arranged outside DC converter station noise equipment under test a directive property sound-conducting apparatus and a laser vibration measurer be set respectively, and make the receiving end of directive property sound-conducting apparatus, laser vibration measurer emitted laser point to tested equipment of direct-current convertor station simultaneously;

(2), send during the equipment under test work that obtains by the directive property sound-conducting apparatus noise signal and the vibration signal on the equipment under test surface that records of laser vibration measurer respectively by anti-aliasing filtering, and be converted to digital signal and send into computing machine and carry out frequency spectrum computing and coherence analysis;

(3), COMPUTER CALCULATION draws the noise signal of the same equipment under test that sends and the coherence function value of vibration signal (promptly relevant frequency spectrum), the noise spectrum of more same equipment under test and relevant frequency spectrum, by relatively drawing the noise source conclusion: the noise at the big frequency place of coherent value is the noise that this equipment surface vibration is produced, coherent value little (as, under given degree of confidence less than 0.8) the noise at frequency place be not that vibration by this equipment under test causes; That is to say that the noise at the big frequency place of coherent value is that institute is produced when being worked by this equipment under test, otherwise the noise at this frequency place just not that institute is produced when being worked by this equipment under test.

Images