CN114744777A - Passive surface-mounted current measurement wireless micro-power consumption sensing system - Google Patents
Passive surface-mounted current measurement wireless micro-power consumption sensing system Download PDFInfo
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- CN114744777A CN114744777A CN202210545371.2A CN202210545371A CN114744777A CN 114744777 A CN114744777 A CN 114744777A CN 202210545371 A CN202210545371 A CN 202210545371A CN 114744777 A CN114744777 A CN 114744777A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
- H02J50/10—Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
- H02J13/00002—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by monitoring
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The invention discloses a wireless micro-power consumption sensing system for passive surface-mounted current measurement, which comprises: the current energy-taking module is used for obtaining electric energy through the current energy-taking device; the micro-power-consumption patch current sensing module is connected with the current energy-taking module and is used for converting a current magnetic field generated by electric energy transmission into an analog electric signal; the micro-control processing module is connected with the micro-power-consumption patch current sensing module and is used for processing the analog electric signal through digital filtering; and the wireless transmission module is connected with the micro-control processing module and used for compiling an http transmission protocol and realizing data communication between the system terminal and the cloud server. According to the invention, through integrated wireless passive power taking, micro-power current monitoring and remote real-time transmission, remote data real-time acquisition and measurement can be realized without additionally laying a power line and a communication line, and the method has higher use value and application prospect in various power monitoring fields.
Description
Technical Field
The invention relates to the technical field of wireless micro-power consumption sensing systems, in particular to a wireless micro-power consumption sensing system for passive surface-mounted current measurement.
Background
In the fields of rail transit, power supply systems and the like, which relate to power monitoring, the sensing of electrical signals generally occurs in train electrical fault diagnosis, train electric energy calculation and energy consumption special diagnosis distribution, and electric power grid electric energy quality analysis and fault judgment. At present, sensing measurement, statistical analysis and passive wireless transmission of electric signals are difficult in non-contact, most of main sensing systems in the market are contact type, active type or non-contact sensing units with relatively large volume, and the traditional wired active contact type measuring scheme has the following limitations:
(1) the sensing system needs large voltage power supply to cause high energy consumption of the system, and a test site is required to have a replaceable large-capacity power supply or an external circuit to obtain a condition of a stable power supply;
(2) the wired active cable wiring relates to the construction of cable ducts, and a large amount of engineering cost, equipment cost, maintenance cost and labor cost need to be consumed in the aspect of engineering;
(3) the touch sensing unit has relatively strict requirements on the field sensing measurement environment, the complexity of physical structure and cable distribution under most measurement scenes is wide, the installation environment of the touch sensor cannot be met, and the wired transmission type has various time-space limitation problems that data transmission is not timely, a designated platform is required for data analysis and downloading, and the like,
disclosure of Invention
The invention aims to provide a passive surface-mounted current measurement wireless micro-power consumption sensing system, and aims to solve the problems of troublesome installation, poor reliability, frequent power supply replacement, untimely data, space-time limitation, higher engineering and labor costs and the like of the traditional contact type active large-power consumption sensing monitoring unit in the current market.
In order to achieve the above object, the present invention provides a wireless micro power consumption sensing system for passive surface-mount current measurement, comprising:
the current energy-taking module is used for obtaining electric energy through the current energy-taking device;
the micro-power-consumption patch current sensing module is connected with the current energy-taking module and is used for converting a current magnetic field generated by electric energy transmission into an analog electric signal;
the micro-control processing module is connected with the micro-power-consumption patch current sensing module and is used for processing the analog electric signal through digital filtering;
and the wireless transmission module is connected with the micro-control processing module and used for compiling an http transmission protocol and realizing data communication between the system terminal and the cloud server.
Preferably, the current energy-taking device includes:
the current energy taking unit is used for winding a current energy taking magnetic ring through the current taking coil loop and connecting a cable to be tested to obtain initial current data;
the electric energy conversion unit is connected with the current energy taking unit and used for rectifying the initial current data through an electric energy conversion circuit to obtain direct current electric energy data;
and the voltage-stabilizing energy storage unit is connected with the electric energy conversion unit and is used for storing the direct current electric energy.
Preferably, the micro power consumption patch current sensing module comprises,
the micro-power consumption sensing unit is connected with the voltage-stabilizing energy storage unit and used for sensing current through a micro-power consumption sensing IC, and a test interface and a temperature compensation interface of the micro-power consumption sensing IC are connected with the decoupling circuit;
the power supply unit is used for connecting the IC power supply and the ground pin through the patch capacitor;
and the voltage stabilizing buffer unit is used for externally connecting the standard zero potential and the digital zero potential of the IC through the voltage stabilizing buffer capacitor.
Preferably, the micro power consumption sensing unit is used for realizing patch measurement through the sensitivity of the current sensor integrated with the magnetic concentrator to magnetic flux density.
Preferably, the micro-control processing module comprises a micro-control processing unit, and the micro-control processing unit comprises a micro-control processor MCU, a crystal oscillator system, an AD conversion circuit and a serial port transmission circuit; the MCU is directly connected with the crystal oscillator system and the AD conversion circuit; and the micro control processor MCU is connected with the wireless transmission module through the serial port transmission circuit.
Preferably, the AD conversion circuit includes:
the sampling conditioning unit is used for sampling, conditioning and analog filtering of the output signal of the micro-power consumption sensing unit through the sampling conditioning circuit;
and the signal conversion unit is used for converting the conditioned analog quantity electric signal into a digital signal.
Preferably, the cloud server is connected to the wireless transmission module, and is configured to implement concurrency performance through a thread pool technology.
Preferably, the cloud server includes:
a creating unit configured to create a child thread in advance;
the response unit is used for responding the request received by the cloud server through the sub thread;
and the maintenance unit is used for maintaining the sub-thread.
Preferably, the system terminal is configured to implement link connection and issue a command through an http protocol thread.
The invention has the technical effects that:
the invention solves the power supply problem of the traditional wiring active type by designing a wireless micro-power consumption sensing system for passive surface-mounted current measurement and utilizing a current loop power-taking technology; the micro-power consumption surface-mounted current sensing technology is utilized to solve the problems of large power consumption, large volume, poor environmental adaptability, complex installation, high cost and large engineering quantity of contact type measuring equipment; the problems of low real-time degree of data, space-time limitation of data summarization and the like of an active cable type sensing system are solved by utilizing a micro-power consumption processing unit and a wireless transmission technology; through adopting the wireless passive electricity of integration, little consumption current monitoring and long-range real-time transmission, realize need not additionally to lay power cord and communication line and just can realize remote data real-time collection measurement, in various electric power monitoring fields, have higher use value and application prospect.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application. In the drawings:
FIG. 1 is a block diagram of a system architecture in an embodiment of the present invention;
FIG. 2 is a schematic diagram of a current energy-extracting device according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a micro-power patch current sensing module according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a schematic framework of a micro-control processing unit in an embodiment of the present invention;
FIG. 5 is a sample conditioning circuit diagram in an embodiment of the invention;
fig. 6 is a schematic diagram of a schematic framework of a signal conversion unit in an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
Example one
With reference to fig. 1, a wireless micro-power consumption sensing system for passive surface-mount current measurement according to an embodiment of the present invention includes a current energy obtaining module, a micro-power consumption patch current sensing module, a micro-control processing module, and a wireless transmission module.
Referring to fig. 2, the current energy-taking module obtains electric energy through a current energy-taking device, and the current energy-taking device includes a current energy-taking unit, an electric energy conversion unit, and a voltage-stabilizing energy storage unit. The getting electric coil loop in the current getting energy unit surrounds the getting energy magnetic ring, and its theory of operation is: when a current i flows through the transmission line of the current loopsAnd (t) generating current at the secondary side of the current loop through electromagnetic induction, wherein the above principle is the basic property of the simplest electricity taking principle about the current transformer. At this time the voltage load u0(t) is in the form of alternating current, and the power consumption in the sensing unit and the micro-power consumption processing unit is direct currentTherefore, should be aligned with u0(t) rectifying; need step down voltage when the rectification, but generally hardly reach the standard, at this moment need DC-DC converter carry out chopping step down once more, make its output voltage accord with the demand of cable monitoring devices to voltage, realize becoming the direct current electric energy with the converter circuit rectification and store the electric energy through steady voltage energy storage circuit.
With reference to fig. 3, the micro power consumption patch current sensing module includes a micro power consumption sensing unit, the micro power consumption sensing unit performs current sensing through a micro power consumption sensing IC (MLX series), and a test interface and a temperature compensation interface of the micro power consumption sensing IC are connected to a decoupling circuit; the power supply unit is connected with an IC power supply and a pin to the ground through a patch capacitor; the voltage-stabilizing buffer unit is used for externally connecting the standard zero potential and the digital zero potential of the IC through a voltage-stabilizing buffer capacitor. The working principle is that a power supply used by the micro-power consumption sensing IC is a single 5V power supply, and the micro-power consumption is realized by reducing the power consumption by six times compared with the power consumption of a +/-15V power supply Hall sensor; when the current cable to be tested passes through the pair of parallel IC surfaces, the output signal generated by the IC is in direct proportion to the horizontally applied magnetic flux density, and the small-size application design and the simple structure are added, so that the micro-power-consumption patch sensor is suitable for realizing micro-power-consumption patch sensing of test current in various current ranges from a few amperes to thousands of amperes.
The micro-power consumption sensing unit is a single-chip sensor IC, and the improved traditional plane Hall technology is only sensitive to the magnetic flux density which is orthogonal to the surface of the integrated circuit. Patch measurements can be achieved by current sensors integrated with magnetic concentrators (IMC-Hall) that are sensitive to magnetic flux density parallel to the IC surface. The principle is to obtain a surface magnetic field through an integrated magnetic concentrator (IMC-Hall) deposited on the sensing cell CMOS die (as an additional back-end step). As a single chip Hall sensor, the output signal of the sensor is proportional to the horizontally applied magnetic flux density, and current measurement is realized. The measuring range can be changed by programming the transmission characteristics, and an output analog signal is obtained.
With reference to fig. 4, the micro control processing module includes a micro control processing unit, and the micro control processing unit includes a micro control processor MCU, a crystal oscillator system, an AD conversion circuit, a serial port transmission circuit, a power module, and an SD card read-write area; the MCU is directly connected with the crystal oscillator system, the AD conversion circuit is connected with the MCU through a conversion signal, and the MCU is connected with the wireless transmission module through a serial port for processing and operation. The micro-control processing unit is mainly used for collecting electric data in real time through the micro-power-consumption patch current sensing module, filtering and denoising the collected data by using a multi-resolution multi-sensor data fusion technology, and then storing the data locally and transmitting the data to a remote upper computer in real time through GPRS wireless transmission.
Furthermore, the micro-control processing module also comprises a power supply area, and a power supply module of the power supply area can adopt STM32 as a main control chip, provide 3.3V and +/-15V working voltage for a sampling conditioning circuit, a wireless communication module and the like, and support an adapter, a USB and a backup power supply mode.
Further, the STM32 main control chip area comprises an STM32 processing chip and peripheral circuits thereof and a ferroelectric temporary storage circuit.
Furthermore, the micro-control processing module also comprises a JTAG programming and SD card reading and writing area, and supports the secondary development of the system and the booting of a program SD.
Further, the serial port transmission circuit interface is an interface for communication of the GPRS wireless transmission module.
Further, the micro control processing unit is provided with an indicator light area for indicating the power supply state of the circuit, the signal transmission state and the like.
Further, the serial port transmission circuit and the wireless transmission module form a transmission network link between the sensing system terminal and the background server based on an http transmission protocol. The thread pool only uses the thread to forward the data, the terminal server is used as a terminal to store the data, and the thread pool uses the thread to realize the database storage of the data. In addition, the terminal server also needs an http protocol thread for realizing the command issuing function, controlling each node device and realizing link communication.
Furthermore, the AD conversion circuit comprises two parts, wherein the first part is a sampling conditioning circuit, the second part is a signal conversion module, the input of the sampling conditioning circuit is connected with the output signal of the micro-power-consumption patch current sensing unit, the output of the sampling conditioning circuit is connected with the input end of the signal conversion module in a one-way mode, and the output digital signal of the signal conversion circuit is directly accessed into the MCU.
(1) The sampling conditioning circuit comprises: sampling, conditioning and analog filtering of the output signal of the micro-power consumption sensing unit are achieved, as shown in fig. 5.
The same sampling current signal is input into the equidirectional proportion and reverse proportion amplifiers, so that the normal conditioning output of the forward direction and the reverse direction of the current sampling signal is ensured, and the forward and reverse directions of the sampling signal can be judged.
The input-output transfer function of the inverting proportional amplifier is as follows:
wherein the proportionality coefficient is as follows: k1 ═ Ra4/Ra2
The input-output transfer function of the in-phase proportional amplifier is as follows:
wherein the proportionality coefficient is: K2-Rb 5/Rb 4-Rb 3/Rb 2;
the maximum voltage drop of the current sampling resistor 250 omega is 5V, so that in order to prevent the chip from being burnt out, the proportionality coefficient of the non-inverting/inverting amplifier is about 0.6, and meanwhile, an RC filter and a limiting output triode are connected to the output end of the operational amplifier, so that the output voltage is ensured not to exceed 3.3V. The conditioning circuit adopts the structure of an integrator, and generates a pole, namely a turning frequency, so as to eliminate the influence of input noise. Meanwhile, according to the input-output proportionality coefficient relationship analyzed above, the resistance-capacitance value in the conditioning circuit can be further determined. The working bandwidth of the inverting proportional amplifier is about 1kHz, and the amplitude attenuation degree at the low-frequency stage is about-4.4 dB, namely 0.6; over the entire operating bandwidth, the phase shift is about 180 ° because of the inverting input; in a high-frequency stage, the amplitude is attenuated by a frequency range with a slope of-20 dB/ten times, so that the influence of high-frequency noise on a sampling signal is effectively inhibited, and the effective treatment performance of the STM32 on the sampling signal is improved. The design of the in-phase proportional amplifier is similar.
(2) The signal conversion module: the conversion of the conditioned analog electrical signal into a digital signal is achieved as shown in fig. 6.
VAIN is an analog signal to be detected, RAIN and Cparastic are filtering voltage-stabilizing capacitance resistance input by a sampling signal to realize sampling for the circuit, VDD is connected with VT clamp to realize signal holding and quantization, the voltage value of the sampled model signal is quantized according to a calculation rule, and the voltage value is coded and output by using 12-bit-converter according to sampling precision, namely a 0-1 digital signal, so that a digital quantity is obtained and output to a digital signal pin of a micro control processor (MCU).
According to the invention, by designing a wireless micro-power consumption sensing system for passive surface-mounted current measurement, the problem of traditional wiring active power supply is solved by using a current loop power-taking technology, and the problems of large power consumption, large volume, poor environmental adaptability, complex installation, high cost and large engineering quantity of contact type measuring equipment are solved by using a micro-power consumption surface-mounted current sensing technology; the problems of low data real-time degree, data collection space-time limitation and the like of an active cable type sensing system are solved by the micro-power consumption processing unit and the wireless transmission technology, and the real-time acquisition and measurement of remote data can be realized without additionally laying a power line and a communication line by adopting integrated wireless passive power taking, micro-power consumption current monitoring and remote real-time transmission.
The above description is only for the preferred embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (9)
1. A wireless micro-power consumption sensing system for passive surface-mounted current measurement is characterized by comprising:
the current energy-taking module is used for obtaining electric energy through the current energy-taking device;
the micro-power-consumption patch current sensing module is connected with the current energy-taking module and is used for converting a current magnetic field generated by electric energy transmission into an analog electric signal;
the micro-control processing module is connected with the micro-power-consumption patch current sensing module and is used for processing the analog electric signal through digital filtering;
and the wireless transmission module is connected with the micro-control processing module and used for compiling an http transmission protocol and realizing data communication between the system terminal and the cloud server.
2. The wireless micropower sensing system of passive surface-mount current measurement according to claim 1, wherein the current energy-taking device comprises:
the current energy taking unit is used for winding a current energy taking magnetic ring through the current taking coil loop and connecting a cable to be tested to obtain initial current data;
the electric energy conversion unit is connected with the current energy taking unit and used for rectifying the initial current data through an electric energy conversion circuit to obtain direct current electric energy data;
and the voltage-stabilizing energy storage unit is connected with the electric energy conversion unit and is used for storing the direct current electric energy.
3. The wireless micro-power consumption sensing system of passive surface-mount current measurement according to claim 1, wherein the micro-power consumption patch current sensing module comprises,
the micro-power consumption sensing unit is connected with the voltage-stabilizing energy storage unit and used for sensing current through a micro-power consumption sensing IC, and a test interface and a temperature compensation interface of the micro-power consumption sensing IC are connected with the decoupling circuit;
the power supply unit is used for connecting the IC power supply and the ground pin through the patch capacitor;
and the voltage-stabilizing buffer unit is used for externally connecting the standard zero potential and the digital zero potential of the IC through a voltage-stabilizing buffer capacitor.
4. The wireless micro-power consumption sensing system of passive surface-mount current measurement according to claim 3,
the micro-power consumption sensing unit is used for realizing the patch measurement through the sensitivity of the current sensor of the integrated magnetic concentrator to the magnetic flux density.
5. The wireless micro-power consumption sensing system of passive surface-mount current measurement according to claim 1,
the micro-control processing module comprises a micro-control processing unit, and the micro-control processing unit comprises a micro-control processor MCU, a crystal oscillator system, an AD conversion circuit and a serial port transmission circuit; the MCU is directly connected with the crystal oscillator system and the AD conversion circuit; and the micro control processor MCU is connected with the wireless transmission module through the serial port transmission circuit.
6. The wireless surface-mounted current-measuring micropower sensing system of claim 5, wherein the AD conversion circuit comprises:
the sampling conditioning unit is used for sampling, conditioning and analog filtering of output signals of the micro-power consumption sensing unit through the sampling conditioning circuit;
and the signal conversion unit is used for converting the conditioned analog quantity electric signal into a digital signal.
7. The wireless micro-power consumption sensing system of passive surface-mount current measurement according to claim 1,
and the cloud server is connected with the wireless transmission module and is used for realizing concurrency performance through a thread pool technology.
8. The wireless micro-power consumption sensing system of passive surface-mount current measurement according to claim 7,
the cloud server comprises:
a creating unit configured to create a child thread in advance;
the response unit is used for responding the request received by the cloud server through the sub thread;
and the maintenance unit is used for maintaining the sub-thread.
9. The wireless micro-power consumption sensing system of passive surface-mount current measurement according to claim 1,
and the system terminal is used for realizing link communication and command issuing through an http protocol thread.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2024103903A1 (en) * | 2022-11-15 | 2024-05-23 | 云南电网有限责任公司电力科学研究院 | Self-energy-harvesting power monitoring device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2024103903A1 (en) * | 2022-11-15 | 2024-05-23 | 云南电网有限责任公司电力科学研究院 | Self-energy-harvesting power monitoring device |
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