CN216771834U - Pulse current receiving module - Google Patents
Pulse current receiving module Download PDFInfo
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- CN216771834U CN216771834U CN202122885876.7U CN202122885876U CN216771834U CN 216771834 U CN216771834 U CN 216771834U CN 202122885876 U CN202122885876 U CN 202122885876U CN 216771834 U CN216771834 U CN 216771834U
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Abstract
A pulsed current receiving module comprising: the magnetic-focusing coil comprises a magnetic-focusing ring, a feedback coil winding, a magnetic sensing chip and a signal processing circuit; the signal processing circuit comprises an analog-to-digital converter, a micro-processing module, a digital-to-analog converter and a power amplifying circuit; the micro-processing module acquires a voltage signal output by the magnetic sensor chip through the analog-to-digital converter; the micro-processing module comprises an orthogonal phase-locked amplifier, a PID controller and a signal discrimination unit which are sequentially connected, the orthogonal phase-locked amplifier is used for frequency selection to obtain a frequency selection signal amplitude, the PID controller is used for calculating a control compensation quantity according to the frequency selection signal amplitude, a digital-to-analog converter is used for converting compensation control voltage waveform data generated based on the control compensation quantity into an analog voltage signal, a power amplification circuit is used for amplifying the analog voltage signal and driving a feedback coil winding to generate a frequency selection feedback magnetic field, and the signal discrimination unit is used for discriminating a pulse current signal according to the frequency selection signal amplitude and the control compensation quantity. The utility model can reduce the overall power consumption of the receiving module.
Description
Technical Field
The utility model belongs to the technical field of current sensing, and particularly relates to a pulse current receiving module for characteristic current signal identification.
Background
The low-voltage transformer area topology identification is an important link for the construction of the intelligent power grid. Because the low-voltage distribution area has a complex circuit structure and large electricity consumption, distribution area files are incomplete, table-changing information is not updated timely, management investment is insufficient, and the like, the reliability of the topological relation of the low-voltage distribution area cannot be ensured. Therefore, topology identification technology needs to be introduced into the low-voltage transformer area to check and correct the existing transformer area topological relation. The existing power distribution area identification technology mainly comprises a data correlation analysis identification technology, a power line carrier voltage injection identification technology and a pulse current input identification technology. The characteristic signals of the data correlation analysis and identification technology are not controllable, and the branch nodes of the topology cannot be identified by the power line carrier voltage injection identification technology, so that the existing low-voltage distribution area topology identification mainly adopts the pulse current injection identification technology.
The pulse current injection identification is mainly realized by a pulse current (topological signal) injection module and a pulse current receiving module. The pulse current injection module is used for injecting the characteristic current signals into the line, and the pulse current receiving module is used for carrying out topology identification according to the characteristic current signals in the line. The pulse current receiving module comprises a pulse current receiving module based on a Rogowski coil and a pulse current receiving module based on a magnetic sensor chip. According to the electromagnetic induction principle, when a pulse single-current signal flows through a primary side of a pulse current receiving module based on a Rogowski coil, the current wound in a secondary side winding of an air-core magnetic gathering ring is in direct proportion to the measured current of the primary side, and the information of the pulse current is restored by processing and analyzing the current signal of the secondary side to judge the topological structure. Compared with a mutual inductor, the Rogowski coil has no magnetic core saturation phenomenon, high bandwidth and low cost, but has lower sensitivity due to the lack of a magnetic core with high magnetic conductivity.
The pulse current receiving module based on the magnetic sensor chip detects a pulse current signal on the primary side through the magnetic sensor chip, converts the pulse current signal into a differential voltage signal and outputs the differential voltage signal; and the pulse current information is restored by analyzing and processing the voltage signal output by the magnetic sensor chip, and the topological structure is judged. Compared with a closed-loop magnetic sensor chip pulse current receiving module, the open-loop magnetic sensor chip pulse current receiving module has the advantages of simple structure and low power consumption, but is low in precision and narrow in bandwidth and not beneficial to detection of pulse current signals. The closed-loop magnetic sensing chip pulse current receiving module has faster response time and accuracy because the magnetic sensing chip works near zero magnetic flux, but improves the whole power consumption because of introducing frequency-selective feedback current.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a pulse current receiving module with low power consumption for identifying the topology of a low-voltage transformer area.
In order to achieve the purpose, the utility model adopts the following technical solutions:
a pulse current receiving module having a through hole for a conductor under test to pass through, comprising: the magnetic sensor comprises a magnetic gathering ring, a feedback coil winding wound on the magnetic gathering ring, a magnetic sensor chip arranged at the notch or the opening of the magnetic gathering ring, and a signal processing circuit connected with the magnetic sensor chip; the signal processing circuit comprises an analog-to-digital converter connected with the magnetic sensor chip, a micro-processing module connected with the analog-to-digital converter, a digital-to-analog converter connected with the micro-processing module, and a power amplifying circuit connected with the digital-to-analog converter; the micro-processing module collects a voltage signal output by the magnetic sensor chip through the analog-to-digital converter; the micro-processing module comprises an orthogonal phase-locked amplifier, a PID controller and a signal discrimination unit which are sequentially connected, the orthogonal phase-locked amplifier is used for carrying out frequency selection to obtain a frequency-selection signal amplitude, the frequency-selection signal amplitude is a signal amplitude with the same frequency as a characteristic pulse current, the PID controller is used for calculating a control compensation quantity according to the frequency-selection signal amplitude, the digital-to-analog converter is used for converting compensation control voltage waveform data generated based on the control compensation quantity into an analog voltage signal, the power amplification circuit is used for amplifying the analog voltage signal and driving the feedback coil winding to generate a frequency-selection feedback magnetic field, the signal discrimination unit is used for carrying out discrimination on a pulse current signal according to the frequency-selection signal amplitude and the control compensation quantity when zero magnetic flux is reached, and when the frequency-selection signal amplitude and the control compensation quantity are 0, the characteristic pulse current signal does not exist in a circuit, otherwise, the pulse current signal exists in the line.
Furthermore, the magnetism gathering ring is an arc-shaped or C-shaped silicon steel sheet or film alloy or a nano wafer or a hollow framework.
Further, the magnetic sensor chip is a TMR chip or a GMR chip.
Furthermore, the signal processing circuit is arranged on the circuit board, and the magnetic sensing chip is connected with the signal processing circuit through a contact pin or a lead.
Furthermore, the signal processing circuit further comprises a power circuit and a communication interface circuit, the power circuit supplies power to the magnetic sensor chip and the signal processing circuit, and the communication interface circuit is used for receiving an instruction of the topology master station and reporting a judgment result.
Furthermore, the device also comprises an input/output terminal, wherein a receiving frequency is preset through the input/output terminal, and the receiving frequency is the same as the frequency of the characteristic pulse current.
Furthermore, the pulse current receiving module is of an open-close type structure.
According to the technical scheme, the pulse current receiving module adopts the magnetic sensor chip and the closed loop structure, and has higher sensitivity compared with the pulse current receiving module with the open loop structure and the pulse current receiving module based on the Rogowski coil type; the micro-processing module in the signal processing circuit of the utility model is provided with an orthogonal frequency-locking amplifier and a PID controller, the output signal of the magnetic sensor chip can be amplified in a phase-locking way according to the preset frequency through the orthogonal frequency-locking amplifier, the frequency-selecting signal amplitude which is the same as the preset frequency is obtained, the frequency-selecting signal amplitude is input into the PID controller to be calculated and reconstructed, the frequency-selecting magnetic balance regulating quantity, namely the control compensation quantity, is reconstructed and output through a digital-to-analog converter based on the frequency-selecting magnetic balance regulating quantity, a feedback coil winding is driven through a power amplifier to generate a frequency-selecting feedback magnetic field, and finally the magnetic sensor chip is installed in a state that the selected frequency reaches a zero magnetic flux state, compared with a common closed loop structure, because the feedback coil winding only has the current with the preset frequency and does not have the current signal related to the carrier in a power line, and thus has lower power consumption.
Drawings
In order to illustrate the embodiments of the present invention more clearly, the drawings that are needed in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings can be obtained by those skilled in the art without inventive effort.
FIG. 1 is a schematic structural diagram of an embodiment of the present invention;
FIG. 2 is a block diagram of a microprocessor module according to an embodiment of the present invention;
fig. 3 is a schematic block diagram of a quadrature phase-locked amplifier and a PID controller according to an embodiment of the present invention.
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
Detailed Description
In describing the utility model in detail and in conjunction with the drawings, the drawings showing the structure of the device are not to scale and are partially enlarged for the sake of illustration, when embodiments of the utility model are described in detail, and the drawings are only exemplary and should not be considered as limiting the scope of the utility model. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is provided solely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.
As shown in fig. 1, the pulse current receiving module of the present embodiment includes a feedback coil winding 1, a magnetic focusing ring 2, a magnetic sensing chip 3, and a signal processing circuit 4, wherein the feedback coil winding 1, the magnetic focusing ring 2, the magnetic sensing chip 3, and the signal processing circuit 4 are all disposed in a housing 5. The shell 5 of this embodiment is an open-close type structure, and includes an upper shell 5-1 and a lower shell 5-2, where the upper shell 5-1 is a semicircular ring and is hinged to the lower shell 5-2, when the upper shell 5-1 rotates, the upper shell 5-1 and the lower shell 5-2 can be opened and closed, when the upper shell 5-1 and the lower shell 5-2 are closed, a through hole 5a for the tested conductor 7 to pass through is formed therebetween, and the shell 5 (receiving module) can be conveniently sleeved on the periphery of the tested conductor 7 by rotating the upper shell 5-1 to perform current detection.
The feedback coil winding 1 is wound on the magnetic gathering ring 2 and used for generating a feedback magnetic field. The magnetic gathering ring 2 of the present embodiment includes a pair of arc-shaped iron cores disposed opposite to each other, and may form a receiving module with an annular opening and closing structure. The magnetism gathering ring 2 can be made of silicon steel sheets, permalloy, nanocrystalline and other magnetic materials, and can also be a hollow framework. A notch 2a is arranged on the magnetism-gathering ring 2, the magnetic sensing chip 3 is arranged at the notch 2a (or opening) of the magnetism-gathering ring 2, the magnetic sensing chip 3 is used for magnetic field detection, and the magnetic sensitivity direction of the magnetic sensing chip 3 is perpendicular to the detected conductor 7. The magnetic sensing chip 3 is connected with the signal processing circuit 4 through pins or wires. The magnetic sensor chip may be a TMR chip or a GMR chip. The signal processing circuit 4 is disposed on a circuit board, and the circuit board is provided with an input/output terminal 6, and the input/output terminal 6 is used for power supply and communication.
As shown in fig. 2, the signal processing circuit 4 of the present embodiment includes an analog-to-digital converter 4-1, a power amplifying circuit 4-2, a digital-to-analog converter 4-3, a micro-processing module 4-4, a power circuit (not shown) and a communication interface circuit (not shown). Analog-to-digital converter 4-1 is connected with the output end of the magnetic sensor chip 3 and is used for receiving a voltage signal V output by the magnetic sensor chip 3MThe analog-to-digital converter 4-1 is connected with the micro-processing module 4-4, the micro-processing module 4-4 is connected with the digital-to-analog converter 4-3, the analog-to-digital converter 4-3 is connected with the power amplification circuit 4-2, the power amplification circuit 4-2 is connected with the feedback coil winding 1, and the power amplification circuit 4-2 outputs feedback current to the feedback coil winding 1 so that the feedback coil winding 1 generates a corresponding feedback magnetic field. The power supply circuit provides stable driving voltage for the magnetic sensor chip 3 and the signal processing circuit 4, and the communication interface circuit is used for receiving an instruction of the topology master station and reporting a topology identification result. The receiving frequency can be preset through the input/output terminal, the receiving frequency is consistent with the frequency of the pulse current detected in the line, and the receiving frequency is a reference signal VROf (c) is detected.
The microprocessing module 4-4 of the present invention further comprises a quadrature phase-locked amplifier 4-41, a PID controller 4-42 and a signal discrimination unit 4-43 connected in sequence. The micro-processing module 4-4 collects the voltage signal output by the magnetic sensor chip 3 through the analog-to-digital converter 4-1, and performs phase-locked amplification on the voltage signal through the quadrature phase-locked amplifier 4-41, extracts the magnetic field signal amplitude near the receiving frequency, then inputs the extracted magnetic field signal amplitude into the PID controller 4-42, calculates and reconstructs the signal according to the magnetic field signal amplitude by the PID controller 4-42 to obtain a frequency-selective magnetic balance regulating quantity U (frequency-selective compensation signal), and after the signal is converted by the digital-to-analog converter 4-3 based on the frequency-selective magnetic balance regulating quantity, the power amplifying circuit 4-2 drives the feedback coil winding 1 to generate a corresponding frequency-selective feedback magnetic field, when the zero magnetic flux is reached (when the frequency-selective feedback magnetic field B is balanced with the magnetic field A generated by the characteristic pulse current), the signal discrimination unit 4-43 generates the output value according to the quadrature phase-locked amplifier 4-41 and the output value of the PID controller 4-42, the pulse current signals with the same frequency as the preset frequency can be extracted to judge the characteristic pulse current.
The signal discrimination process of the present invention is described below with reference to fig. 1, 2 and 3:
a tested conductor 7 penetrates through a through hole 5a of a shell 5, when a master station starts topology identification, a pulse current injection module injects a characteristic pulse current signal into the tested conductor 7, and a magnetic field A is generated around the tested conductor 7;
the magnetic sensing chip 3 detects the magnetic field at the notch 2a of the poly-magnetic ring 2 and outputs a differential voltage signal V containing fundamental wave (characteristic pulse current signal) and carrier wave characteristicsM；
The micro-processing module 4-4 collects a differential voltage signal V output by the magnetic sensing chip 3 through the analog-to-digital converter 4-1MQuadrature lock-in amplifier 4-41 from VMThe signal amplitude value which is the same as the preset frequency is extracted, namely, the quadrature phase-locked amplifier 4-41 carries out frequency selection to obtain the frequency-selecting signal amplitude value R, the quadrature phase-locked amplifier 4-41 outputs the frequency-selecting signal amplitude value R to the PID controller 4-42, the PID controller 4-42 calculates the control compensation quantity U according to the frequency-selecting signal amplitude value R (the output of the phase-locked amplifier), the calculation process of the output (the control compensation quantity U) of the PID controller is a conventional calculation process (see figure 3), which is not an innovation of the utility model, and is not repeated here, the compensation control voltage waveform data can be generated based on the control compensation quantity U, the digital-to-analog converter 4-4 converts the compensation control voltage waveform data into a corresponding analog voltage signal Vs, and the feedback coil winding 1 is driven by the power amplifying circuit 4-2 to generate a feedback magnetic field B with a preset frequency;
when the gap 2a (under the preset frequency) is in zero magnetic flux, the pulse current receiving module is in a stable state, the output (U) of the PID controller 4-42 is in direct proportion to the reference signal of the preset frequency, and when the reference signal is the same as the characteristic pulse current signal, the signal discrimination unit 4-43 analyzes the output R of the quadrature phase-locked amplifier 4-41 and the output U of the PID controller 4-42 at the moment, so that the topological pulse current signal can be discriminated.
The distinguishing process of the characteristic pulse current is as follows:
when the current (characteristic pulse current signal) with the same frequency as the reference signal exists in the circuit, the output R of the phase-locked amplifier is the voltage proportional to the amplitude of the current signal with the same frequency, and when the characteristic pulse current signal does not exist in the circuit, the output R of the phase-locked amplifier is 0;
when the output R of the phase-locked amplifier is not 0, the PID controller calculates the control compensation amount U according to R, when the output R of the phase-locked amplifier is 0, the output of the PID controller is also close to 0, the change trends of the output R of the phase-locked amplifier and the output U of the PID controller are the same, and only the numerical values are possibly different, so that whether a characteristic pulse current signal exists or not can be judged by judging whether the output R of the phase-locked amplifier and the output U of the PID controller are 0 or not, when the output R of the phase-locked amplifier and the output U of the PID controller are 0, the characteristic pulse current signal does not exist in a line, and otherwise, the pulse current signal exists in the line.
The receiving module can send the judgment result of the pulse current signal back to the sending module, and the sending module is used for distinguishing different characteristic pulse current signals by modulating the existence/nonexistence of the characteristic pulse current signal. When the topology of the transformer area is identified, it is assumed that each sending module has an address, the sending module controls whether a pulse current signal exists in a line according to the binary coding of the address, and the receiving module can decode and restore the corresponding sending module address according to the output of the R, so that the topology identification is realized.
Since only the current with the preset frequency exists in the feedback coil winding of the embodiment, no current signal related to the carrier in the power line exists, and therefore power consumption is reduced.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the utility model. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. A pulse current receiving module having a through hole for a conductor under test to pass through, comprising: the magnetic sensor comprises a magnetic gathering ring, a feedback coil winding wound on the magnetic gathering ring, a magnetic sensor chip arranged at the notch or the opening of the magnetic gathering ring, and a signal processing circuit connected with the magnetic sensor chip;
the method is characterized in that:
the signal processing circuit comprises an analog-to-digital converter connected with the magnetic sensor chip, a micro-processing module connected with the analog-to-digital converter, a digital-to-analog converter connected with the micro-processing module, and a power amplifying circuit connected with the digital-to-analog converter; the micro-processing module collects a voltage signal output by the magnetic sensor chip through the analog-to-digital converter; the micro-processing module comprises an orthogonal phase-locked amplifier, a PID controller and a signal discrimination unit which are sequentially connected, the orthogonal phase-locked amplifier is used for carrying out frequency selection to obtain a frequency-selection signal amplitude, the frequency-selection signal amplitude is a signal amplitude which is the same as the characteristic pulse current frequency, the PID controller is used for calculating a control compensation quantity according to the frequency-selection signal amplitude, the digital-to-analog converter is used for converting compensation control voltage waveform data generated based on the control compensation quantity into an analog voltage signal, the power amplification circuit is used for amplifying the analog voltage signal and driving the feedback coil winding to generate a frequency-selection feedback magnetic field, the signal discrimination unit is used for carrying out discrimination on a pulse current signal according to the frequency-selection signal amplitude and the control compensation quantity when the zero magnetic flux is reached, and when the frequency-selection signal amplitude and the control compensation quantity are 0, and judging that the characteristic pulse current signal does not exist in the line, otherwise, judging that the pulse current signal exists in the line.
2. The pulsed current receiving module of claim 1, wherein: the magnetism gathering ring is an arc-shaped or C-shaped silicon steel sheet or film alloy or a nano wafer or a hollow framework.
3. The pulsed current receiving module of claim 1, wherein: the magnetic sensor chip is a TMR chip or a GMR chip.
4. The pulsed current receiving module of claim 1, wherein: the signal processing circuit is arranged on the circuit board, and the magnetic sensing chip is connected with the signal processing circuit through a contact pin or a lead.
5. The pulsed current receiving module of claim 1, wherein: the signal processing circuit further comprises a power circuit and a communication interface circuit, the power circuit supplies power to the magnetic sensor chip and the signal processing circuit, and the communication interface circuit is used for receiving an instruction of the topology master station and reporting a judgment result.
6. The pulsed current receiving module of claim 1, wherein: the pulse current detection circuit further comprises an input/output terminal, wherein a receiving frequency is preset through the input/output terminal, and the receiving frequency is the same as the frequency of the characteristic pulse current.
7. The pulsed current receiving module of claim 1, wherein: the pulse current receiving module is of an open-close type structure.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115684701A (en) * | 2023-01-01 | 2023-02-03 | 华中科技大学 | High-resolution wide-range magnetic modulation type direct current sensor based on differential demodulation |
| CN117805466A (en) * | 2023-12-27 | 2024-04-02 | 珠海多创科技有限公司 | Weak current signal detection method, weak current signal detection device, topology identification device and station area identification system |
-
2021
- 2021-11-22 CN CN202122885876.7U patent/CN216771834U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115684701A (en) * | 2023-01-01 | 2023-02-03 | 华中科技大学 | High-resolution wide-range magnetic modulation type direct current sensor based on differential demodulation |
| CN115684701B (en) * | 2023-01-01 | 2023-04-18 | 华中科技大学 | High-resolution wide-range magnetic modulation type direct current sensor based on differential demodulation |
| CN117805466A (en) * | 2023-12-27 | 2024-04-02 | 珠海多创科技有限公司 | Weak current signal detection method, weak current signal detection device, topology identification device and station area identification system |
| CN117805466B (en) * | 2023-12-27 | 2024-05-17 | 珠海多创科技有限公司 | Weak current signal detection method, weak current signal detection device, topology identification device and station area identification system |
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