CN210720587U

CN210720587U - Power line noise acquisition circuit

Info

Publication number: CN210720587U
Application number: CN201921227790.1U
Authority: CN
Inventors: 陈育培; 孙延松; 吴达雷; 陈龙瑾; 黄开来
Original assignee: Hainan Power Grid Co Ltd
Current assignee: Hainan Power Grid Co Ltd
Priority date: 2019-07-31
Filing date: 2019-07-31
Publication date: 2020-06-09
Anticipated expiration: 2029-07-31

Abstract

The utility model provides a power line noise acquisition circuit, wherein a power line is connected with a coupling circuit, the coupling circuit is electrically connected with a signal conditioning circuit, a PGA circuit, an ADC circuit and a DSP circuit in turn, the signal conditioning circuit comprises a grading circuit, a follower circuit, a first analog switch circuit and a second analog switch circuit, first LC high pass filter circuit, second LC high pass filter circuit, hierarchical circuit's output links to each other with follower circuit, first analog switch circuit electrical property in proper order, and an output of first analog switch circuit links to each other with first LC high pass filter circuit electrical property, and another output links to each other with second LC high pass filter circuit electrical property, and first LC high pass filter circuit, second LC high pass filter circuit's output all link to each other with second analog switch circuit electrical property, the utility model discloses make things convenient for on-the-spot fortune dimension personnel to judge the influence of on-the-spot power line environment to carrier communication.

Description

Power line noise acquisition circuit

Technical Field

The utility model relates to a power line detects technical field, especially relates to a power line noise acquisition circuit.

Background

At present, the common power line carrier channel noise test method mainly uses an oscilloscope to perform time domain noise test, and uses a spectrum analyzer to perform frequency domain noise test. Because the spectrum analyzer and the digital oscilloscope are high-precision professional signal testing instruments, the spectrum analyzer and the digital oscilloscope have large volume and poor portability, are only suitable for the environment of a laboratory and are not suitable for being used in various complicated power fields

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a power line noise acquisition circuit, noise signal in the collection scene power line that can be swift, convenient makes things convenient for scene fortune dimension personnel to judge the influence of scene power line environment to carrier communication.

The utility model discloses a realize through following technical scheme: a power line noise acquisition circuit comprises a power line, wherein the power line is connected with a coupling circuit, the coupling circuit is sequentially electrically connected with a signal conditioning circuit, a PGA circuit, an ADC circuit and a DSP circuit, the DSP circuit is in signal interconnection with an upper computer, the signal conditioning circuit comprises a grading circuit, a follower circuit, a first analog switch circuit, a second analog switch circuit, a first LC high-pass filter circuit and a second LC high-pass filter circuit, the coupling circuit is connected into the grading circuit, the output end of the grading circuit is sequentially electrically connected with the follower circuit and the first analog switch circuit, the first analog switch circuit is provided with two output ends, one of the two output ends is electrically connected with the first analog switch circuit, the other output end is electrically connected with the second analog switch circuit, and the output ends of the first analog switch circuit and the second analog switch circuit are electrically connected with the second analog switch circuit, and the output end of the second analog switch circuit is electrically connected with the PGA circuit, the ADC circuit and the DSP circuit in sequence.

Preferably, the classification circuit comprises a first classification circuit, a second classification circuit, a third classification circuit and a fourth classification circuit, the first classification circuit, the second classification circuit, the third classification circuit and the fourth classification circuit are connected in series, and the first classification circuit, the second classification circuit, the third classification circuit and the fourth classification circuit are used for dividing the amplitude of the noise signal into four grades.

Preferably, the follower circuit is comprised of an operational amplifier with an OPA353 chip.

Preferably, the PGA circuit is composed of an AD8370 chip.

Preferably, the ADC circuit uses the ADC10080 chip of TI.

Preferably, the DSP circuit comprises a DSP control circuit formed by a TMS320C6748 chip.

Preferably, the DSP circuit is also electrically connected with the MCU controller, and the MCU controller is connected with the upper computer through a Bluetooth signal.

Compared with the prior art, the utility model discloses the beneficial effect who reaches as follows:

the utility model provides a pair of power line noise acquisition circuit, be used for keeping apart the forceful electric power in the power line through coupling circuit, hierarchical circuit through in the signal conditioning circuit can divide into 4 grades with the noise signal range simultaneously, reduce the impedance through the follower circuit, through first LC high pass filter circuit, second LC high pass filter circuit divides the noise frequency range into and is greater than 50K and be greater than two frequency ranges of 700K, and first analog switch circuit, second analog switch circuit is used for switching the noise signal of two frequency ranges, the noise signal who obtains as required is through PGA circuit amplification back, gather by the ADC circuit again, the noise signal who gathers is transmitted and is analyzed in the DSP circuit. The utility model discloses the noise frequency point is come out in the analysis to can in time inform on-the-spot fortune dimension personnel, make things convenient for on-the-spot fortune dimension personnel to judge on-the-spot power line environment to carrier communication's influence.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only preferred embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive effort.

Fig. 1 is the utility model provides a power line noise acquisition circuit's structure chart.

Fig. 2 is a schematic diagram of a signal conditioning circuit according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a PGA circuit according to an embodiment of the present invention;

fig. 4 is a schematic diagram of an ADC circuit provided by an embodiment of the present invention.

In the figure, 1-an upper computer, 2-an MCU controller, 3-Bluetooth, 4-DSP circuit, 5-coupling circuit, 6-signal conditioning circuit, 7-PGA circuit and 8-ADC circuit.

Detailed Description

In order to better understand the technical content of the present invention, the following embodiments are provided, and the present invention is further described with reference to the accompanying drawings.

Referring to fig. 1 to 4, a power line noise collection circuit comprises a power line, the power line is connected with a coupling circuit 5, the coupling circuit 5 is sequentially electrically connected with a signal conditioning circuit 6, a PGA circuit 7, an ADC circuit 8, and a DSP circuit 4, the DSP circuit 4 is signal-interconnected with an upper computer 1, the signal conditioning circuit 6 comprises a grading circuit, a follower circuit, a first analog switch circuit, a second analog switch circuit, a first LC high-pass filter circuit, and a second LC high-pass filter circuit, the coupling circuit 5 is connected into the grading circuit, the output end of the grading circuit is sequentially electrically connected with the follower circuit and the first analog switch circuit, the first analog switch circuit has two output ends, one of the output ends is electrically connected with the first analog switch circuit, and the other output end is electrically connected with the second analog switch circuit, the output ends of the first analog switch circuit and the second analog switch circuit are electrically connected with the second analog switch circuit, and the output end of the second analog switch circuit is electrically connected with the PGA circuit 7, the ADC circuit 8 and the DSP circuit 4 in sequence.

Specifically, the power line is electrically connected with a signal conditioning circuit 6 through a coupling circuit 5, the coupling circuit 5 is used for isolating strong electricity, coupling power line noise signals and carrier signals, the signal conditioning circuit 6 comprises a grading circuit, a follower circuit, a first analog switch circuit, a second analog switch circuit, a first LC high-pass filter circuit and a second LC high-pass filter circuit, the grading circuit is used for dividing the amplitude of the noise signals obtained by the coupling circuit 5 into 4 grades, and meanwhile, the input impedance is reduced through the follower circuit;

as shown in fig. 1, the first LC high-pass filter circuit is an LC high-pass filter composed of L5, L6, L7 and peripheral capacitance of 700K, and the second LC high-pass filter circuit is an LC high-pass filter composed of L11, L12, L13 and peripheral capacitance of 50K;

the first analog switch circuit and the second analog switch circuit are used for switching noise signals of two frequency bands, when the first analog switch circuit and the second analog switch circuit are in a double-open state, the first analog switch circuit and the second analog switch circuit are selected, and the first LC high-pass filter outputs noise signals of more than 700K; when the first analog switch circuit and the second analog switch circuit are in a double-closed state, namely the second LC high-pass filter circuit is selected, the second LC high-pass filter circuit outputs a noise signal of more than 50K.

Specifically, the classification circuit comprises a first classification circuit, a second classification circuit, a third classification circuit and a fourth classification circuit, wherein the first classification circuit, the second classification circuit, the third classification circuit and the fourth classification circuit are respectively formed by a relay K1\ K2\ K3\ K4 and a voltage dividing resistor R1, R7, R16 and R21, the first classification circuit, the second classification circuit, the third classification circuit and the fourth classification circuit are connected in series, and the first classification circuit, the second classification circuit, the third classification circuit and the fourth classification circuit are used for dividing the amplitude of the noise signal into four levels.

Specifically, the follower circuit is composed of an operational amplifier with an OPA353 chip, and the composed follower circuit can effectively reduce input impedance.

Specifically, as shown in fig. 3, the PGA circuit 7 includes an AD8370 chip, a peripheral capacitor, and an inductor, where the AD8370 chip can amplify the obtained noise signal of 50K or more or 700K or more, the AD8370 chip has a resolution of 2dB, a low gain range of-11 dB to +17dB, a high gain range of 6dB to 34dB, and a bandwidth of 750 MHz. The high resolution and wide gain range enable the test data to be more accurate;

meanwhile, in fig. 3, the peripheral capacitors C33, C34, C31, C32, the inductors L2, L4, L3, L8, L10, and L9 of the PGA circuit 7 form a low-pass filter for low-pass filtering the amplified signal, so that the data acquired by the ADC is more accurate.

Specifically, the ADC circuit 8 uses an ADC10080 chip of TI, a differential input mode, 10-bit sampling precision, and a sampling rate of 80M, and for a 12M broadband carrier signal, the number of sampling points is greater than 6, so that a 12M waveform can be analyzed, and sampling of a noise signal can be realized by the ADC circuit 8.

Specifically, DSP circuit 4 includes the DSP control circuit who constitutes by TMS320C6748 chip, just DSP circuit 4 still links to each other with MCU controller 2 electrical property, MCU controller 2 passes through bluetooth 3 and links to each other with host computer 1 signal.

The working principle is as follows: when the circuit is used, the coupling circuit 5 is connected with a power line, the amplitude of the obtained noise signal is divided into four grades under the action of the first classification circuit, the second classification circuit, the third classification circuit and the fourth classification circuit, the first LC high-pass filter circuit or the second LC high-pass filter circuit is selected through the first analog switch circuit and the second analog switch circuit, when the first analog switch circuit and the second analog switch circuit are in a double-open state, the first LC high-pass filter circuit is selected, and the first LC high-pass filter outputs a noise signal of more than 700K; when the first analog switch circuit and the second analog switch circuit are in a double-closed state, the second LC high-pass filter circuit is selected, the second LC high-pass filter circuit outputs noise signals above 50K, the output noise signals are sent to the PGA circuit 7 by the second analog switch circuit to be amplified, the noise signals are collected by the ADC circuit 8 after being amplified, the noise signals are converted into digital signals and then are transmitted to the DSP chip to be analyzed, the analyzed noise data are converted into information recognized by the Bluetooth 3 through the MCU controller 2, and the information is sent to the upper computer 1 through the Bluetooth 3.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A power line noise acquisition circuit comprises a power line and is characterized in that the power line is connected with a coupling circuit, the coupling circuit is sequentially electrically connected with a signal conditioning circuit, a PGA circuit, an ADC circuit and a DSP circuit, the DSP circuit is in signal interconnection with an upper computer, the signal conditioning circuit comprises a grading circuit, a follower circuit, a first analog switch circuit, a second analog switch circuit, a first LC high-pass filter circuit and a second LC high-pass filter circuit, the coupling circuit is connected into the grading circuit, the output end of the grading circuit is sequentially electrically connected with the follower circuit and the first analog switch circuit, the first analog switch circuit is provided with two output ends, one output end is electrically connected with the first LC high-pass filter circuit, and the other output end is electrically connected with the second LC high-pass filter circuit, the output ends of the first LC high-pass filter circuit and the second LC high-pass filter circuit are electrically connected with the second analog switch circuit, and the output end of the second analog switch circuit is electrically connected with the PGA circuit, the ADC circuit and the DSP circuit in sequence.

2. The power line noise collection circuit of claim 1, wherein the classification circuit comprises a first classification circuit, a second classification circuit, a third classification circuit, and a fourth classification circuit, the first classification circuit, the second classification circuit, the third classification circuit, and the fourth classification circuit are connected in series with each other, and the first classification circuit, the second classification circuit, the third classification circuit, and the fourth classification circuit are configured to classify the noise signal amplitude into four classes.

3. The power line noise collection circuit of claim 1, wherein said follower circuit is comprised of an operational amplifier with an OPA353 chip.

4. The power line noise collection circuit of claim 1, wherein the PGA circuit is formed using an AD8370 chip.

5. The power line noise collection circuit of claim 1, wherein said ADC circuit uses the ADC10080 chip of TI.

6. The power line noise collection circuit of claim 1, wherein the DSP circuit comprises a DSP control circuit formed from a TMS320C6748 chip.

7. The power line noise collection circuit of claim 1, wherein the DSP circuit is further electrically connected to an MCU controller, and the MCU controller is connected to the upper computer via bluetooth.