CN105301546A - Ultrasonic partial discharge tester verification method and system - Google Patents

Abstract

The invention provides an ultrasonic partial discharge tester verification method. The ultrasonic partial discharge tester verification method takes y=sin(x)/x or an exponential function signal as a modulation signal for amplitude modulation, and takes a sine wave signal as a carrier wave signal; when the modulation signal is amplified by a power amplifier, an ultrasonic emission oscillator is driven and an ultrasonic signal waveform which is highly similar to a field partial discharge ultrasonic signal is output; the measurement frequency band, the amplitude linearity error and the pulse counting error of the detected ultrasonic partial discharge tester are respectively verified; and the waveform number of the ultrasonic signal can be adjusted in unit time so that the discharge pulse counting function of the detected ultrasonic partial discharge tester can be examined and the amplitude and the frequency of the sine wave signal can be fixed or can be continuously adjusted and the verification of the measurement frequency band and the amplitude measurement linearity error of the detected ultrasonic partial discharge tester can be effectively realized.

Description

A kind of ultrasound wave instrument for measuring partial discharge method of calibration and system

Technical field

The application relates to field of power, particularly a kind of ultrasound wave instrument for measuring partial discharge method of calibration and system.

Background technology

Along with the development of technology, the requirement of people to ultrasound wave instrument for measuring partial discharge method of calibration is more and more higher.

Existing in ultrasound wave instrument for measuring partial discharge method of calibration, adopt standard signal source as the hyperacoustic pumping signal of generation, these standard signal sources can not produce when actual electric power apparatus local discharge occurs, cause departing from the verification of ultrasound wave instrument for measuring partial discharge and actual service condition, authenticity is poor.

Therefore, how effectively to carry out the verification of ultrasound wave instrument for measuring partial discharge, improve the authenticity of verification, so that better realizing the examination of ultrasound wave instrument for measuring partial discharge technical feature is the current technical issues that need to address of those skilled in the art.

Summary of the invention

Technical problems to be solved in this application are to provide a kind of ultrasound wave instrument for measuring partial discharge method of calibration, on the basis of original check system, utilize signal modulating method to simulate actual Processing of Partial Discharge Ultrasonic Signals, substitute the sinusoidal wave standard signal source in original system, can truly, effectively verify ultrasound wave instrument for measuring partial discharge.

Its concrete scheme is as follows:

A kind of ultrasound wave instrument for measuring partial discharge method of calibration, the method comprises:

With y=sin (x)/x or the exponential function signal modulation signal as amplitude modulation(PAM), with sine wave signal as carrier signal, modulation signal is after power amplifier amplifies, drive ultrasound wave to launch oscillator, export the ultrasonic signal waveform similar to on-the-spot Processing of Partial Discharge Ultrasonic Signals height;

According to the ultrasonic signal waveform of described output, respectively the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, amplitude linearity error and step-by-step counting error are verified.

Above-mentioned method, preferably, the described ultrasonic signal waveform according to described output, verifies the measurement frequency band of ultrasound wave instrument for measuring partial discharge, comprising:

According to the ultrasound wave waveform of described output, determine upper cut-off frequency and the lower-cut-off frequency of described ultrasound wave instrument for measuring partial discharge;

By formula calculate the error of described tested ultrasound wave instrument for measuring partial discharge upper and lower limit cutoff frequency;

In formula: γ _ffor the relative error of tester upper and lower limit cutoff frequency; f _bfor tester upper and lower limit cutoff frequency nominal value; F is tester upper and lower limit cutoff frequency measured value.

Above-mentioned method, preferably, the described ultrasound wave waveform according to described output, determine upper cut-off frequency and the lower-cut-off frequency of described ultrasound wave instrument for measuring partial discharge, comprising:

Change the amplitude of described carrier signal, make described tested ultrasound wave instrument for measuring partial discharge display amplitude at 20% of its full scale;

Measure in frequency band range in the nominal of described tested ultrasound wave instrument for measuring partial discharge, change the frequency of described carrier signal, find out described tested ultrasound wave instrument for measuring partial discharge and measure amplitude maximum point;

Record the described display amplitude of tested ultrasound wave instrument for measuring partial discharge and the frequency values of described carrier signal;

With described frequency values point for benchmark, reduce the frequency values of described carrier signal, find out Frequency point when described tested ultrasound wave instrument for measuring partial discharge displayed value decreases by 6dB, the Frequency point recorded when described display amplitude reaches 6dB is the lower-cut-off frequency of actual measurement;

With described frequency values point for benchmark, increase the frequency values of described carrier signal, find out the upper cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge.

Above-mentioned method, preferably, the described ultrasonic signal waveform according to described output, verifies the amplitude linearity error of ultrasound wave instrument for measuring partial discharge, comprising:

Within the scope of the frequency measurement of described tested ultrasound wave instrument for measuring partial discharge, the frequency of carrier signal is set, slowly regulates its amplitude, make described tested ultrasound wave instrument for measuring partial discharge reach its full scale value;

Record the amplitude of described carrier signal;

Reduce the amplitude of described carrier signal, make the amplitude of described carrier signal keep twice decay;

Record the displayed value of described tested ultrasound wave instrument for measuring partial discharge at each point;

By formula Δ A _x=A _{x (n)}-A _{x (n-1)}calculate its amplitude display pad value;

By formula $\mathrm{\Δ}\mathrm{\γ}=\frac{{\mathrm{\ΔA}}_x-6}{6}\×100\%$ Calculate its amplitude linearity error;

In formula: Δ A _xfor the amplitude display pad value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; A _{x (n)}, A _{x (n-1)}for the displayed value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; Δ γ is described tested ultrasound wave instrument for measuring partial discharge amplitude linear measurement relative error.

Above-mentioned method, preferably, the described ultrasonic signal waveform according to described output, verifies the step-by-step counting error of ultrasound wave instrument for measuring partial discharge, comprising:

Measure in frequency band range in described tested ultrasound wave instrument for measuring partial discharge, the described carrier signal of a fixed frequency is set, changes the frequency of described modulation signal, peak value number in the ultrasonic signal waveform unit interval that described output is set;

Record described tested ultrasound wave instrument for measuring partial discharge pulse counter display value;

By formula ${\mathrm{\γ}}_n=\frac{n_x-n_0}{n_0}\×100\%$ Calculate step-by-step counting error;

In formula: γ _n-by school tester step-by-step counting measuring error, n _x-by school tester step-by-step counting measured value, n ₀-by school tester step-by-step counting setting value.

A kind of ultrasound wave instrument for measuring partial discharge check system, this system comprises:

Output unit, for with y=sin (x)/x or the exponential function signal modulation signal as amplitude modulation(PAM), with sine wave signal as carrier signal, modulation signal is after power amplifier amplifies, drive ultrasound wave to launch oscillator, export the ultrasonic signal waveform similar to on-the-spot Processing of Partial Discharge Ultrasonic Signals height;

Verification unit, for the ultrasonic signal waveform according to described output, verifies the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, amplitude linearity error and step-by-step counting error respectively.

Above-mentioned system, preferably, described verification unit comprises:

Determining unit, for the ultrasound wave waveform according to described output, determines upper cut-off frequency and the lower-cut-off frequency of described ultrasound wave instrument for measuring partial discharge;

First computing unit, for pressing formula calculate the error of described tested ultrasound wave instrument for measuring partial discharge upper and lower limit cutoff frequency;

In formula: γ _ffor the relative error of tester upper and lower limit cutoff frequency; f _bfor tester upper and lower limit cutoff frequency nominal value; F is tester upper and lower limit cutoff frequency measured value.

Above-mentioned system, preferably, described determining unit comprises:

First changes unit, for changing the amplitude of described carrier signal, makes described tested ultrasound wave instrument for measuring partial discharge display amplitude at 20% of its full scale;

Second changes unit, for measuring in frequency band range in the nominal of described tested ultrasound wave instrument for measuring partial discharge, changes the frequency of described carrier signal, finds out described tested ultrasound wave instrument for measuring partial discharge and measures amplitude maximum point;

First record cell, for recording the described display amplitude of tested ultrasound wave instrument for measuring partial discharge and the frequency values of described carrier signal;

Second record cell, for with described frequency values point for benchmark, reduce the frequency values of described carrier signal, find out Frequency point when described tested ultrasound wave instrument for measuring partial discharge displayed value decreases by 6dB, the Frequency point recorded when described display amplitude reaches 6dB is the lower-cut-off frequency of actual measurement;

3rd record cell, for described frequency values point for benchmark, increase the frequency values of described carrier signal, record the upper cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge.

Above-mentioned system, preferably, described verification unit comprises:

First setting unit, within the scope of the frequency measurement of described tested ultrasound wave instrument for measuring partial discharge, arranges the frequency of carrier signal, slowly regulates its amplitude, makes described tested ultrasound wave instrument for measuring partial discharge reach its full scale value;

4th record cell, for recording the amplitude of described carrier signal;

Attenuation units, for reducing the amplitude of described carrier signal, makes the amplitude of described carrier signal keep twice decay;

5th record cell, for recording the displayed value of described tested ultrasound wave instrument for measuring partial discharge at each point;

Second computing unit, for pressing formula Δ A _x=A _{x (n)}-A _{x (n-1)}calculate its amplitude display pad value;

3rd computing unit, for pressing formula calculate its amplitude linearity error;

In formula: Δ A _xfor the amplitude display pad value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; A _{x (n)}, A _{x (n-1)}for the displayed value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; Δ γ is described tested ultrasound wave instrument for measuring partial discharge amplitude linear measurement relative error.

Above-mentioned system, preferably, described verification unit comprises:

Second setting unit, for measuring in frequency band range in described tested ultrasound wave instrument for measuring partial discharge, the described carrier signal of one fixed frequency is set, changes the frequency of described modulation signal, peak value number in the ultrasonic signal waveform unit interval that described output is set;

6th record cell, for recording described tested ultrasound wave instrument for measuring partial discharge pulse counter display value;

4th computing unit, for pressing formula calculate step-by-step counting error;

In formula: γ _n-by school tester step-by-step counting measuring error, n _x-by school tester step-by-step counting measured value, n ₀-by school tester step-by-step counting setting value.

In a kind of ultrasound wave instrument for measuring partial discharge method of calibration that the application provides, with y=sin (x)/x or the exponential function signal modulation signal as amplitude modulation(PAM), with sine wave signal as carrier signal, modulation signal is after power amplifier amplifies, drive ultrasound wave to launch oscillator, export the ultrasonic signal waveform similar to on-the-spot Processing of Partial Discharge Ultrasonic Signals height; According to the ultrasonic signal waveform of described output, respectively the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, amplitude linearity error and step-by-step counting error are verified.The ultrasonic signal produced in the application can realize the realistic simulation of ultrasonic signal when producing actual electric power apparatus local discharge, described ultrasonic signal waveform number within the unit interval can regulate, thus the discharge pulse tally function of tested ultrasound wave instrument for measuring partial discharge can be examined, and sine wave signal amplitude and frequency can be fixed and also can be regulated continuously, thus effectively can realize the verification of tested ultrasound wave instrument for measuring partial discharge being measured to frequency band and amplitude measurement linear error.

Accompanying drawing explanation

In order to be illustrated more clearly in the technical scheme in the embodiment of the present application, below the accompanying drawing used required in describing embodiment is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the application, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 is the process flow diagram of a kind of ultrasound wave instrument for measuring partial discharge method of calibration embodiment of the application;

Fig. 2 is existing ultrasound wave instrument for measuring partial discharge checking system structural drawing;

Fig. 3 is that in the application's ultrasound wave instrument for measuring partial discharge checking system, ultrasonic excitation signals produces structural drawing;

Fig. 4 is the process flow diagram of a kind of ultrasound wave instrument for measuring partial discharge measurement frequency band method of calibration embodiment of the application;

Fig. 5 is the process flow diagram of a kind of ultrasound wave instrument for measuring partial discharge amplitude linearity error method of calibration embodiment of the application;

Fig. 6 is the process flow diagram of a kind of ultrasound wave instrument for measuring partial discharge step-by-step counting error checking embodiment of the method for the application;

Fig. 7 is the schematic diagram of a kind of ultrasound wave instrument for measuring partial discharge check system embodiment of the application.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present application, be clearly and completely described the technical scheme in the embodiment of the present application, obviously, described embodiment is only some embodiments of the present application, instead of whole embodiments.Based on the embodiment in the application, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the application's protection.

With reference to figure 1, show the process flow diagram of a kind of ultrasound wave instrument for measuring partial discharge of the application method of calibration embodiment, can comprise the following steps:

Step S101: with y=sin (x)/x or the exponential function signal modulation signal as amplitude modulation(PAM), with sine wave signal as carrier signal, modulation signal is after power amplifier amplifies, drive ultrasound wave to launch oscillator, export the ultrasonic signal waveform similar to on-the-spot Processing of Partial Discharge Ultrasonic Signals height.

As shown in Figure 2, standard signal source is for generation of ultrasonic excitation signals for the Organization Chart of existing ultrasound wave instrument for measuring partial discharge check system.For improving signal source carrying load ability, after standard signal source exports, connecing a power amplifier, then amplified signal being accessed standard ultrasonic emission sensor.Standard transducer and oscillograph form gauge measurement system, for Real-Time Monitoring emission sensor output ultrasonic wave intensity; Be close to emission sensor surface by school tester sensor, after ultrasonic signal is converted into electric signal, export measurement main frame to.

And in the application, sinusoidal wave standard signal source is replaced with signal modulating method, as shown in Figure 3, for realizing the realistic simulation to actual Processing of Partial Discharge Ultrasonic Signals, the application adopts amplitude modulation(PAM) mode: use y=sin (x)/x or exponential function signal as modulation signal, with sine wave signal as carrier signal, modulation signal amplifies through power amplifier, drive ultrasound wave to launch oscillator, thus the perfection of the ultrasonic signal waveform and actual Processing of Partial Discharge Ultrasonic Signals that reach output is simulated.

Step S102: according to the ultrasonic signal waveform of described output, verifies the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, amplitude linearity error and step-by-step counting error respectively.

Utilize the signal extremely close with ultrasonic signal during actual electric power apparatus local discharge as ultrasonic excitation signals, make the follow-up verification to ultrasound wave instrument for measuring partial discharge more true, accurate.

In a kind of ultrasound wave instrument for measuring partial discharge method of calibration that the application provides, the ultrasonic signal produced can realize the realistic simulation of ultrasonic signal when producing actual electric power apparatus local discharge, described ultrasonic signal waveform number within the unit interval can regulate, thus the discharge pulse tally function of tested ultrasound wave instrument for measuring partial discharge can be examined, and sine wave signal amplitude and frequency can be fixed and also can be regulated continuously, thus effectively can realize the verification of tested ultrasound wave instrument for measuring partial discharge being measured to frequency band and amplitude measurement linear error.

With reference to figure 4, show the process flow diagram that frequency band method of calibration is measured by a kind of ultrasound wave instrument for measuring partial discharge of the application, can comprise the following steps:

Step S401: the amplitude changing described carrier signal, makes described tested ultrasound wave instrument for measuring partial discharge display amplitude at 20% of its full scale.

Step S402: measure in frequency band range in the nominal of described tested ultrasound wave instrument for measuring partial discharge, change the frequency of described carrier signal, finds out described tested ultrasound wave instrument for measuring partial discharge and measures amplitude maximum point.

Step S403: record the described display amplitude of tested ultrasound wave instrument for measuring partial discharge and the frequency values of described carrier signal.

Step S404: with described frequency values point for benchmark, reduce the frequency values of described carrier signal, find out Frequency point when described tested ultrasound wave instrument for measuring partial discharge displayed value decreases by 6dB, the Frequency point recorded when described display amplitude reaches 6dB is the lower-cut-off frequency of actual measurement.

Step S405: with described frequency values point for benchmark, increase the frequency values of described carrier signal, finds out the upper cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge.

Step S406: by formula calculate the error of described tested ultrasound wave instrument for measuring partial discharge upper and lower limit cutoff frequency, in formula: γ _ffor the relative error of tester upper and lower limit cutoff frequency; f _bfor tester upper and lower limit cutoff frequency nominal value; F is tester upper and lower limit cutoff frequency measured value.

With reference to figure 5, show the process flow diagram of a kind of ultrasound wave instrument for measuring partial discharge of the application amplitude linearity error method of calibration, can comprise the following steps:

Step S501: within the scope of the frequency measurement of described tested ultrasound wave instrument for measuring partial discharge, arrange the frequency of carrier signal, slowly regulates its amplitude, makes described tested ultrasound wave instrument for measuring partial discharge reach its full scale value.

Step S502: the amplitude recording described carrier signal.

Step S503: the amplitude reducing described carrier signal, makes the amplitude of described carrier signal keep twice decay.

Step S504: record the displayed value of described tested ultrasound wave instrument for measuring partial discharge at each point.

Step S505: by formula Δ A _x=A _{x (n)}-A _{x (n-1)}calculate its amplitude display pad value.

Step S506: by formula calculate its amplitude linearity error.

In formula: Δ A _xfor the amplitude display pad value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; A _{x (n)}, A _{x (n-1)}for the displayed value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; Δ γ is described tested ultrasound wave instrument for measuring partial discharge amplitude linear measurement relative error.

With reference to figure 6, show the process flow diagram of a kind of ultrasound wave instrument for measuring partial discharge of the application step-by-step counting error checking method, can comprise the following steps:

Step S601: measure in frequency band range in described tested ultrasound wave instrument for measuring partial discharge, the described carrier signal of a fixed frequency is set, changes the frequency of described modulation signal, peak value number in the ultrasonic signal waveform unit interval that described output is set.

Step S602: record described tested ultrasound wave instrument for measuring partial discharge pulse counter display value.

Step S603: by formula calculate step-by-step counting error.

In formula: γ _n-by school tester step-by-step counting measuring error, n _x-by school tester step-by-step counting measured value, n ₀-by school tester step-by-step counting setting value.

Corresponding with the method that a kind of ultrasound wave of above-mentioned the application instrument for measuring partial discharge method of calibration embodiment provides, see Fig. 7, present invention also provides a kind of ultrasound wave instrument for measuring partial discharge check system embodiment, in the present embodiment, this system comprises:

Output unit 701, for with y=sin (x)/x or the exponential function signal modulation signal as amplitude modulation(PAM), with sine wave signal as carrier signal, modulation signal is after power amplifier amplifies, drive ultrasound wave to launch oscillator, export the ultrasonic signal waveform that on-the-spot Processing of Partial Discharge Ultrasonic Signals height is similar.

Verification unit 702, for the ultrasonic signal waveform according to described output, verifies the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, amplitude linearity error and step-by-step counting error respectively.

Described verification unit comprises:

Determining unit, for the ultrasound wave waveform according to described output, determines upper cut-off frequency and the lower-cut-off frequency of described ultrasound wave instrument for measuring partial discharge.

First computing unit, for pressing formula calculate the error of described tested ultrasound wave instrument for measuring partial discharge upper and lower limit cutoff frequency.

In formula: γ _ffor the relative error of tester upper and lower limit cutoff frequency; f _bfor tester upper and lower limit cutoff frequency nominal value; F is tester upper and lower limit cutoff frequency measured value.

Described determining unit comprises:

First changes unit, for changing the amplitude of described carrier signal, makes described tested ultrasound wave instrument for measuring partial discharge display amplitude at 20% of its full scale.

Second changes unit, for measuring in frequency band range in the nominal of described tested ultrasound wave instrument for measuring partial discharge, changes the frequency of described carrier signal, finds out described tested ultrasound wave instrument for measuring partial discharge and measures amplitude maximum point.

First record cell, for recording the described display amplitude of tested ultrasound wave instrument for measuring partial discharge and the frequency values of described carrier signal.

Second record cell, for with described frequency values point for benchmark, reduce the frequency values of described carrier signal, find out Frequency point when described tested ultrasound wave instrument for measuring partial discharge displayed value decreases by 6dB, the Frequency point recorded when described display amplitude reaches 6dB is the lower-cut-off frequency of actual measurement.

3rd record cell, for described frequency values point for benchmark, increase the frequency values of described carrier signal, record the upper cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge.

Described verification unit comprises:

First setting unit, within the scope of the frequency measurement of described tested ultrasound wave instrument for measuring partial discharge, arranges the frequency of carrier signal, slowly regulates its amplitude, makes described tested ultrasound wave instrument for measuring partial discharge reach its full scale value.

4th record cell, for recording the amplitude of described carrier signal.

Attenuation units, for reducing the amplitude of described carrier signal, makes the amplitude of described carrier signal keep twice decay.

5th record cell, for recording the displayed value of described tested ultrasound wave instrument for measuring partial discharge at each point.

Second computing unit, for pressing formula Δ A _x=A _{x (n)}-A _{x (n-1)}calculate its amplitude display pad value.

3rd computing unit, for pressing formula calculate its amplitude linearity error.

In formula: Δ A _xfor the amplitude display pad value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; A _{x (n)}, A _{x (n-1)}for the displayed value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; Δ γ is described tested ultrasound wave instrument for measuring partial discharge amplitude linear measurement relative error.

Described verification unit comprises:

Second setting unit, for measuring in frequency band range in described tested ultrasound wave instrument for measuring partial discharge, the described carrier signal of one fixed frequency is set, changes the frequency of described modulation signal, peak value number in the ultrasonic signal waveform unit interval that described output is set.

6th record cell, for recording described tested ultrasound wave instrument for measuring partial discharge pulse counter display value.

4th computing unit, for pressing formula calculate step-by-step counting error.

In formula: γ _n-by school tester step-by-step counting measuring error, n _x-by school tester step-by-step counting measured value, n ₀-by school tester step-by-step counting setting value.

It should be noted that, each embodiment in this instructions all adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar part mutually see.For device class embodiment, due to itself and embodiment of the method basic simlarity, so description is fairly simple, relevant part illustrates see the part of embodiment of the method.

Finally, also it should be noted that, in this article, the such as relational terms of first and second grades and so on is only used for an entity or operation to separate with another entity or operational zone, and not necessarily requires or imply the relation that there is any this reality between these entities or operation or sequentially.And, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thus make to comprise the process of a series of key element, method, article or equipment and not only comprise those key elements, but also comprise other key elements clearly do not listed, or also comprise by the intrinsic key element of this process, method, article or equipment.When not more restrictions, the key element limited by statement " comprising ... ", and be not precluded within process, method, article or the equipment comprising described key element and also there is other identical element.

For convenience of description, various unit is divided into describe respectively with function when describing above device.Certainly, the function of each unit can be realized in same or multiple software and/or hardware when implementing the application.

As seen through the above description of the embodiments, those skilled in the art can be well understood to the mode that the application can add required general hardware platform by software and realizes.Based on such understanding, the technical scheme of the application can embody with the form of software product the part that prior art contributes in essence in other words, this computer software product can be stored in storage medium, as ROM/RAM, magnetic disc, CD etc., comprising some instructions in order to make a computer equipment (can be personal computer, server, or the network equipment etc.) perform the method described in some part of each embodiment of the application or embodiment.

A kind of ultrasound wave instrument for measuring partial discharge method of calibration provided the application above and system are described in detail, apply specific case herein to set forth the principle of the application and embodiment, the explanation of above embodiment is just for helping method and the core concept thereof of understanding the application; Meanwhile, for one of ordinary skill in the art, according to the thought of the application, all will change in specific embodiments and applications, in sum, this description should not be construed as the restriction to the application.

Claims (10)

1. a ultrasound wave instrument for measuring partial discharge method of calibration, it is characterized in that, the method comprises:

With y=sin (x)/x or the exponential function signal modulation signal as amplitude modulation(PAM), with sine wave signal as carrier signal, modulation signal is after power amplifier amplifies, drive ultrasound wave to launch oscillator, export the ultrasonic signal waveform similar to on-the-spot Processing of Partial Discharge Ultrasonic Signals height;

According to the ultrasonic signal waveform exported, respectively the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, amplitude linearity error and step-by-step counting error are verified.

2. method according to claim 1, is characterized in that, the described ultrasonic signal waveform according to exporting, verifies the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, comprising:

According to the ultrasound wave waveform of described output, determine upper cut-off frequency and the lower-cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge;

By formula calculate the error of described tested ultrasound wave instrument for measuring partial discharge upper and lower limit cutoff frequency;

In formula: γ _ffor the relative error of tester upper and lower limit cutoff frequency; f _bfor tester upper and lower limit cutoff frequency nominal value; F is tester upper and lower limit cutoff frequency measured value.

3. method according to claim 2, is characterized in that, the described ultrasound wave waveform according to exporting, and determines upper cut-off frequency and the lower-cut-off frequency of described ultrasound wave instrument for measuring partial discharge, comprising:

Change the amplitude of described carrier signal, make described tested ultrasound wave instrument for measuring partial discharge display amplitude at 20% of its full scale;

Measure in frequency band range in the nominal of described tested ultrasound wave instrument for measuring partial discharge, change the frequency of described carrier signal, find out described tested ultrasound wave instrument for measuring partial discharge and measure amplitude maximum point;

Record the described display amplitude of tested ultrasound wave instrument for measuring partial discharge and the frequency values of described carrier signal;

With described frequency values point for benchmark, reduce the frequency values of described carrier signal, find out Frequency point when described tested ultrasound wave instrument for measuring partial discharge displayed value decreases by 6dB, the Frequency point recorded when described display amplitude reaches 6dB is the lower-cut-off frequency of actual measurement;

With described frequency values point for benchmark, increase the frequency values of described carrier signal, find out the upper cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge.

4. method according to claim 1, is characterized in that, the described ultrasonic signal waveform according to exporting, verifies the amplitude linearity error of tested ultrasound wave instrument for measuring partial discharge, comprising:

Within the scope of the frequency measurement of described tested ultrasound wave instrument for measuring partial discharge, the frequency of carrier signal is set, slowly regulates its amplitude, make described tested ultrasound wave instrument for measuring partial discharge reach its full scale value;

Record the amplitude of described carrier signal;

Reduce the amplitude of described carrier signal, make the amplitude of described carrier signal keep twice decay;

Record the displayed value of described tested ultrasound wave instrument for measuring partial discharge at each point;

By formula Δ A _x=A _{x (n)}-A _{x (n-1)}calculate its amplitude display pad value;

By formula calculate its amplitude linearity error;

In formula: Δ A _xfor the amplitude display pad value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; A _{x (n)}, A _{x (n-1)}for the displayed value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; Δ γ is described tested ultrasound wave instrument for measuring partial discharge amplitude linear measurement relative error.

5. method according to claim 1, is characterized in that, the described ultrasonic signal waveform according to exporting, verifies the step-by-step counting error of tested ultrasound wave instrument for measuring partial discharge, comprising:

Measure in frequency band range in described tested ultrasound wave instrument for measuring partial discharge, the described carrier signal of a fixed frequency is set, changes the frequency of described modulation signal, peak value number in the ultrasonic signal waveform unit interval that described output is set;

Record described tested ultrasound wave instrument for measuring partial discharge pulse counter display value;

By formula calculate step-by-step counting error;

In formula: γ _n-by school tester step-by-step counting measuring error, n _x-by school tester step-by-step counting measured value, n ₀-by school tester step-by-step counting setting value.

6. a ultrasound wave instrument for measuring partial discharge check system, is characterized in that, this system comprises:

Output unit, for with y=sin (x)/x or the exponential function signal modulation signal as amplitude modulation(PAM), with sine wave signal as carrier signal, modulation signal is after power amplifier amplifies, drive ultrasound wave to launch oscillator, export the ultrasonic signal waveform similar to on-the-spot Processing of Partial Discharge Ultrasonic Signals height;

Verification unit, for according to the ultrasonic signal waveform exported, verifies the measurement frequency band of tested ultrasound wave instrument for measuring partial discharge, amplitude linearity error and step-by-step counting error respectively.

7. system according to claim 6, is characterized in that, described verification unit comprises:

Determining unit, for the ultrasound wave waveform according to described output, determines upper cut-off frequency and the lower-cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge;

First computing unit, for pressing formula calculate the error of described tested ultrasound wave instrument for measuring partial discharge upper and lower limit cutoff frequency;

In formula: γ _ffor the relative error of tester upper and lower limit cutoff frequency; f _bfor tester upper and lower limit cutoff frequency nominal value; F is tester upper and lower limit cutoff frequency measured value.

8. system according to claim 7, is characterized in that, described determining unit comprises:

First changes unit, for changing the amplitude of described carrier signal, makes described tested ultrasound wave instrument for measuring partial discharge display amplitude at 20% of its full scale;

Second changes unit, for measuring in frequency band range in the nominal of described tested ultrasound wave instrument for measuring partial discharge, changes the frequency of described carrier signal, finds out described tested ultrasound wave instrument for measuring partial discharge and measures amplitude maximum point;

First record cell, for recording the described display amplitude of tested ultrasound wave instrument for measuring partial discharge and the frequency values of described carrier signal;

Second record cell, for with described frequency values point for benchmark, reduce the frequency values of described carrier signal, find out Frequency point when described tested ultrasound wave instrument for measuring partial discharge displayed value decreases by 6dB, the Frequency point recorded when described display amplitude reaches 6dB is the lower-cut-off frequency of actual measurement;

3rd record cell, for described frequency values point for benchmark, increase the frequency values of described carrier signal, record the upper cut-off frequency of described tested ultrasound wave instrument for measuring partial discharge.

9. system according to claim 6, is characterized in that, described verification unit comprises:

First setting unit, within the scope of the frequency measurement of described tested ultrasound wave instrument for measuring partial discharge, arranges the frequency of carrier signal, slowly regulates its amplitude, makes described tested ultrasound wave instrument for measuring partial discharge reach its full scale value;

4th record cell, for recording the amplitude of described carrier signal;

Attenuation units, for reducing the amplitude of described carrier signal, makes the amplitude of described carrier signal keep twice decay;

5th record cell, for recording the displayed value of described tested ultrasound wave instrument for measuring partial discharge at each point;

Second computing unit, for pressing formula Δ A _x=A _{x (n)}-A _{x (n-1)}calculate its amplitude display pad value;

3rd computing unit, for pressing formula calculate its amplitude linearity error;

In formula: Δ A _xfor the amplitude display pad value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; A _{x (n)}, A _{x (n-1)}for the displayed value of described tested ultrasound wave instrument for measuring partial discharge twice adjacent calibration point in front and back; Δ γ is described tested ultrasound wave instrument for measuring partial discharge amplitude linear measurement relative error.

10. system according to claim 6, is characterized in that, described verification unit comprises:

Second setting unit, for measuring in frequency band range in described tested ultrasound wave instrument for measuring partial discharge, the described carrier signal of one fixed frequency is set, changes the frequency of described modulation signal, peak value number in the ultrasonic signal waveform unit interval that described output is set;

6th record cell, for recording described tested ultrasound wave instrument for measuring partial discharge pulse counter display value;

4th computing unit, for pressing formula calculate step-by-step counting error;

In formula: γ _n-by school tester step-by-step counting measuring error, n _x-by school tester step-by-step counting measured value, n ₀-by school tester step-by-step counting setting value.