CN115277291B - MBUS anti-interference device for cold chain - Google Patents
MBUS anti-interference device for cold chain Download PDFInfo
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- CN115277291B CN115277291B CN202210862654.XA CN202210862654A CN115277291B CN 115277291 B CN115277291 B CN 115277291B CN 202210862654 A CN202210862654 A CN 202210862654A CN 115277291 B CN115277291 B CN 115277291B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L12/40006—Architecture of a communication node
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L12/403—Bus networks with centralised control, e.g. polling
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L2012/40208—Bus networks characterized by the use of a particular bus standard
- H04L2012/40228—Modbus
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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
- Y02D10/00—Energy efficient computing, e.g. low power processors, power management or thermal management
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Small-Scale Networks (AREA)
- Dc Digital Transmission (AREA)
Abstract
The invention discloses an MBUS anti-interference device for a cold chain, which belongs to the technical field of cold chain MBUS equipment and comprises the following components: an MBUS bus coupled with a master station and a plurality of slave stations; a current adaptive circuit coupled to the MBUS bus and capable of adjusting a reference voltage when the slave station communicates to the MBUS bus according to a quiescent current of the MBUS bus; the communication interference suppression circuit is respectively coupled with the MBUS bus and the slave station, and can keep current amplification of the MBUS bus stable when the slave station communicates with the MBUS bus; the invention can detect the static current of the MBUS bus in real time by utilizing the current self-adaptive circuit and adjust the reference voltage when the slave station communicates to the MBUS bus according to the static current, thereby realizing the correction of the reference voltage before the master station receives data; the communication interference suppression circuit can compensate the current amplitude of the slave station when communicating to the MBUS bus, so that the current sent by the slave station to the MBUS bus is kept unchanged; the current self-adaptive circuit and the communication interference suppression circuit work together, so that the reliability and the anti-interference performance of the slave station during communication are improved.
Description
Technical Field
The invention relates to the technical field of cold chain MBUS equipment, in particular to an MBUS anti-interference device for a cold chain.
Background
The MBUS bus communication technology has the characteristics of no polarity and multistage cascade connection, has lower requirement on a transmission line, and is widely applied to light-load remote meter reading systems such as water meters, electric meters, gas meters and the like. The master station transmits a voltage mode, namely the master station realizes data transmission to the slave station by changing the bus voltage value, the silence state is 1, and when the bus voltage generates a voltage drop of 12V, the master station transmits data 0 to the slave station; the slave station is in a current mode, namely the slave station realizes communication with the master station by changing the current, the bus current is less than or equal to 1.5mA when the slave station is in silence, and is in a state of '1', and if the slave station wants to send data '0', the bus current needs to be increased by 11-20mA.
When the environment parameter safety detection in the cold chain industry is carried out, the MBUS bus is adopted for data transmission, so that the method is a simple and convenient communication scheme. Because the MBUS bus technology is derived from an application place such as remote meter reading, the defects of the MBUS bus technology are mainly manifested in inadaptability to a high-load system, and the interference of large current can lead to the reduction of communication signal-to-noise ratio and reliability, so that the power limit to a remote load is more strict, the current consumption of a remote slave station in a silent state is generally required to be not more than 3mA, the remote slave station has a data acquisition function, and the MBUS bus silent current can be generally ignored under the limited number of slave stations; however, when the number of the secondary stations exceeds the limit value, the superposition of the silent currents of the secondary stations can cause the static current of the MBUS bus to increase, and when the secondary stations send data to the primary station, the voltage change of the MBUS bus is too small, so that the data transmission fails.
In the cold chain industry, because of the existence of high power consumption units such as a remote alarm device, a remote slave station display module and the like, the silent current of the remote slave station is larger (more than or equal to 200 mA), at the moment, the traditional MBUS bus communication technology cannot completely meet the requirements of industrial production sites, and technical improvements are required from the aspects of software mechanisms and hardware circuits, so that the self-adaptive detection and comparison of the bus quiescent current are realized, and the reliability and the adaptability of the MBUS bus technology are improved.
Disclosure of Invention
For the problems in the prior art, the MBUS anti-interference device for the cold chain provided by the invention can detect the static current of the MBUS bus in real time by using the current self-adaptive circuit and adjust the reference voltage when the slave station communicates to the MBUS bus according to the static current, so that the correction of the reference voltage before the master station receives data is realized; the communication interference suppression circuit can compensate the current amplitude of the slave station when communicating to the MBUS bus, particularly when the slave station is in a high-load state, so that the sending current of the slave station to the MBUS bus is kept unchanged; the current self-adaptive circuit and the communication interference suppression circuit work together, so that the reliability and the anti-interference performance of the slave station during communication are improved.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
an MBUS anti-jamming device for a cold chain, comprising:
an MBUS bus, on which a master station and a plurality of slave stations are coupled;
a current adaptive circuit coupled to the MBUS bus, the current adaptive circuit capable of adjusting a reference voltage of the slave station when communicating to the MBUS bus according to a quiescent current of the MBUS bus;
and the communication interference suppression circuit is respectively coupled with the MBUS bus and the slave station, and can keep the current amplification of the MBUS bus stable when the slave station communicates to the MBUS bus.
As a preferred technical scheme, the current self-adaptive circuit comprises a master station receiving circuit, a voltage following circuit, a PWM circuit and a signal comparing circuit, wherein the input end of the master station receiving circuit is coupled with the MBUS bus, the input end of the voltage following circuit is coupled with the output end of the master station receiving circuit, the output end of the PWM circuit and the output end of the voltage following circuit are both coupled with the input end of the signal comparing circuit, and the output end of the signal comparing circuit is coupled with the input end of the master station.
As an optimized technical scheme, the master station receiving circuit comprises a bus measuring resistor and a current detection amplifying component, wherein the bus measuring resistor is connected in series with the MBUS bus, the input end of the current detection amplifying component is respectively coupled with two ends of the bus measuring resistor, and the output end of the current detection amplifying component is coupled with the input end of the voltage follower circuit.
As a preferred embodiment, the current detection amplifying assembly is configured as a current sensor.
As a preferable technical scheme, a filter circuit is arranged between the PWM circuit and the signal comparison circuit, an output end of the PWM circuit is coupled with the filter circuit, and an output end of the filter circuit is coupled with the signal comparison circuit.
As a preferred technical scheme, the signal comparison circuit is set as a data table, the output end of the filter circuit and the output end of the voltage follower circuit are both coupled with the input end of the data table, and the output end of the data table is coupled with the input end of the master station.
As a preferred embodiment, the communication interference suppression circuit includes a slave station transmitting circuit and a current source compensation circuit.
As a preferable technical scheme, the secondary station transmitting circuit comprises a power end, a parallel resistor, a first triode and a second triode which are sequentially coupled, wherein the output end of the second triode is a signal output end.
As a preferred technical solution, the current source compensation circuit includes an analog-to-digital conversion integrated chip, an output end of the analog-to-digital conversion integrated chip is coupled with a comparator, and an output end of the comparator is coupled with the MBUS bus.
As a preferred solution, a triode is coupled between the comparator and the MBUS bus.
The beneficial effects of the invention are as follows:
the invention can detect the static current of the MBUS bus in real time by utilizing the current self-adaptive circuit and adjust the reference voltage when the slave station communicates to the MBUS bus according to the static current, thereby realizing the correction of the reference voltage before the master station receives data; the communication interference suppression circuit can compensate the current amplitude of the slave station when communicating to the MBUS bus, particularly when the slave station is in a high-load state, so that the sending current of the slave station to the MBUS bus is kept unchanged; the current self-adaptive circuit and the communication interference suppression circuit work together, so that the reliability and the anti-interference performance of the slave station during communication are improved.
Drawings
FIG. 1 is a circuit diagram of a master station receiving circuit in an MBUS anti-jamming device for a cold chain according to the present invention;
FIG. 2 is a circuit diagram of a voltage follower circuit in an MBUS anti-jamming device for a cold chain according to the present invention;
FIG. 3 is a circuit diagram of a signal comparison circuit in an MBUS anti-jamming device for a cold chain according to the present invention;
FIG. 4 is a circuit diagram of a filter circuit in an MBUS anti-jamming device for a cold chain according to the present invention;
FIG. 5 is a circuit diagram of a secondary station transmit circuit in an MBUS tamper resistant apparatus for a cold chain in accordance with the present invention;
fig. 6 is a circuit diagram of a current source compensation circuit in an MBUS anti-interference device for a cold chain according to the present invention.
Detailed Description
The present invention is further described below with reference to the accompanying drawings for the convenience of understanding by those skilled in the art.
Referring to fig. 1-6, an embodiment of an MBUS anti-interference device for a cold chain according to the present invention includes:
an MBUS bus, on which a master station and a plurality of slave stations are coupled, the master station and the slave stations realizing communication through the MBUS bus;
the current self-adaptive circuit is coupled with the MBUS bus, can adjust the reference voltage when the slave station communicates to the MBUS bus according to the static current of the MBUS bus, detects the static current on the MBUS bus in real time, adjusts the reference voltage when the slave station communicates to the MBUS bus according to the static current, and realizes the correction of the reference voltage before the master station receives data;
and the communication interference suppression circuit is respectively coupled with the MBUS bus and the slave station, can keep the current amplification of the MBUS bus stable when the slave station communicates to the MBUS bus, can compensate the current of the slave station when communicating to the MBUS bus, and can keep the transmitting current of the slave station on the MBUS bus unchanged particularly when the slave station is in a high-load state.
In this embodiment, referring to fig. 1 to 4, the current adaptive circuit includes a master station receiving circuit, a voltage follower circuit, a PWM circuit, and a signal comparing circuit, where an input end of the master station receiving circuit is coupled to the MBUS bus, and the master station receiving circuit is configured to detect a quiescent current of the MBUS bus in real time and output an amplified voltage signal; the input end of the voltage follower circuit is coupled with the output end of the master station receiving circuit, and the voltage follower circuit receives the amplified voltage signal and improves the output impedance of the voltage signal; the output end of the PWM circuit and the output end of the voltage follower circuit are both coupled with the input end of the signal comparison circuit, the PWM circuit is used for outputting a comparison value, and the signal comparison circuit can output a stable sending signal after comparing the voltage signal with the comparison value; the output of the signal comparison circuit is coupled to the input of the master station, which can receive the stable transmit signal.
On the basis of the foregoing embodiments, referring to fig. 1 and 2, the master station receiving circuit includes a bus measurement resistor (r_mea) and a CURRENT detection amplifying assembly (INA 168), the bus measurement resistor (r_mea) is connected in series to the MBUS bus, the input terminals of the CURRENT detection amplifying assembly (INA 168) are respectively coupled to two ends of the bus measurement resistor (r_mea), and the CURRENT detection amplifying assembly (INA 168) is configured to detect real-time CURRENT on the bus measurement resistor (r_mea) and output an amplified voltage signal at the output terminal (current_mea); specifically, the current sense amp assembly is preferably configured as a current sensor with signal INA 168; the output (current_mea) of the CURRENT sense amplifier assembly (INA 168) is coupled to the input of the voltage follower circuit.
On the basis of the foregoing embodiment, referring to fig. 4, a filter circuit is disposed between the PWM circuit and the signal comparison circuit, and an output terminal (mcu_pwm) of the PWM circuit is coupled to the filter circuit; specifically, the filter circuit may include two filter capacitors (C11 and C12) to implement filtering of the comparison value of the PWM circuit; the output (current_ref) of the filter circuit is coupled to the signal comparison circuit.
On the basis of the foregoing embodiments, referring to fig. 2 and 3, the signal comparison circuit is preferably set as a data table (TLV 3201), the output end (current_ref) of the filter circuit and the output end (mcu_ad 0) of the voltage follower circuit are both coupled to the input end of the data table (TLV 3201), the output end of the data table (TLV 3201) is coupled to the input end of the master station, and the master station can receive the stable transmission signal sent by the data table (TLV 3201); specifically, the model of the data table is preferably set as a TLV3201, the master station is set as a singlechip, and the singlechip is coupled with the data table (TLV 3201) through a serial port receiving pin.
In this embodiment, referring to fig. 5 and 6, the communication interference suppression circuit includes a secondary station transmitting circuit and a current source compensation circuit, and the secondary station transmitting circuit can improve the convenience of transmitting current and reduce power; the current source compensation circuit compensates the bus current reduction amplitude when the slave station transmits data, so that the bus current can reach the design value, and the reliability of data transmission is ensured.
On the basis of the foregoing embodiment, referring to fig. 5, the slave station transmitting circuit includes a power supply terminal (vdd+), parallel resistors (R4 and R5), a first triode (Q2) and a second triode (Q1) coupled in sequence, where the output terminal of the second triode (Q1) is a signal output terminal, and the switching speed of the first triode (Q2) is faster than that of the conventional optocoupler, so that current can be conveniently transmitted; parallel resistors (R4 and R5) can reduce power.
On the basis of the foregoing embodiment, referring to fig. 6, the current source compensation circuit includes an analog-to-digital conversion integrated chip, an output end of the analog-to-digital conversion integrated chip is coupled with a comparator, an output end of the comparator is coupled with the MBUS bus, and the analog-to-digital conversion integrated chip can compensate a current reduction amplitude of the MBUS bus when the slave station sends data, so that the current of the MBUS bus can reach a design value, and the reliability of data transmission is ensured; specifically, the model of the analog-to-digital conversion integrated chip is preferably set to DAC0808; in this embodiment, the current source compensation circuit is capable of compensating a maximum current of 44.7 mA; further, transistors (Q3 and Q4) are coupled between the comparator and the MBUS bus.
The specific operation mode of the invention is as follows:
after the main station sends a command, waiting for 2ms to play a role in current recovery stability of the MBUS bus, amplifying the current of the MBUS bus 10 times through a current detection amplifying component (INA 168), outputting MCU_AD0 after passing through a voltage follower circuit, and obtaining four samples to obtain an average value of bus current detection value mV after analog-digital conversion of a singlechip. Setting the sending current of the slave station as mA, taking the voltage offset into consideration of the reliability of voltage comparisonmV, the reference voltage at the front end of the comparator is set to +.>mV; setting a count value of a PWM register in a range of 0-255 corresponding to a range of 0-5000 mV of reference voltage of an 8-bit PWM register of a singlechip system>The new reference voltage of the comparator can be obtained after low-pass filtering, so that the reference voltage is corrected before data is received, and the reliability of communication is improved.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. An MBUS anti-jamming device for a cold chain, comprising:
an MBUS bus, on which a master station and a plurality of slave stations are coupled;
a current adaptive circuit coupled to the MBUS bus, the current adaptive circuit capable of adjusting a reference voltage of the slave station when communicating to the MBUS bus according to a quiescent current of the MBUS bus; the current self-adaptive circuit comprises a main station receiving circuit, a voltage following circuit, a PWM circuit and a signal comparison circuit, wherein the input end of the main station receiving circuit is coupled with the MBUS bus, the input end of the voltage following circuit is coupled with the output end of the main station receiving circuit, the output end of the PWM circuit and the output end of the voltage following circuit are both coupled with the input end of the signal comparison circuit, and the output end of the signal comparison circuit is coupled with the input end of the main station;
and the communication interference suppression circuit is respectively coupled with the MBUS bus and the slave station, and can keep the current amplification of the MBUS bus stable when the slave station communicates to the MBUS bus.
2. The MBUS anti-interference device for a cold chain according to claim 1, wherein the master station receiving circuit includes a bus measuring resistor and a current detecting and amplifying component, the bus measuring resistor is connected in series on the MBUS bus, input ends of the current detecting and amplifying component are respectively coupled with two ends of the bus measuring resistor, and output ends of the current detecting and amplifying component are coupled with input ends of the voltage follower circuit.
3. The MBUS anti-jamming device for a cold chain according to claim 2, wherein the current detection amplifying assembly is provided as a current sensor.
4. The MBUS anti-interference device for a cold chain according to claim 1, wherein a filter circuit is arranged between the PWM circuit and the signal comparison circuit, an output end of the PWM circuit is coupled with the filter circuit, and an output end of the filter circuit is coupled with the signal comparison circuit.
5. The MBUS anti-interference device for a cold chain according to claim 4, wherein the signal comparison circuit is configured as a data table, the output of the filter circuit and the output of the voltage follower circuit are both coupled to an input of the data table, and the output of the data table is coupled to an input of the master station.
6. The MBUS anti-interference device for a cold chain according to claim 1, wherein the communication interference suppression circuit includes a slave station transmitting circuit and a current source compensation circuit.
7. The MBUS anti-interference device for a cold chain according to claim 6, wherein the secondary station transmitting circuit includes a power source terminal, a parallel resistor, a first triode and a second triode coupled in sequence, and an output terminal of the second triode is a signal output terminal.
8. The MBUS anti-jamming device for a cold chain according to claim 6, wherein the current source compensation circuit includes a mode conversion integrated chip, an output of the mode conversion integrated chip being coupled with a comparator, an output of the comparator being coupled with the MBUS bus.
9. The MBUS anti-jamming device for a cold chain according to claim 8, wherein a triode is coupled between the comparator and the MBUS bus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210862654.XA CN115277291B (en) | 2022-07-22 | 2022-07-22 | MBUS anti-interference device for cold chain |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210862654.XA CN115277291B (en) | 2022-07-22 | 2022-07-22 | MBUS anti-interference device for cold chain |
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| CN115277291A CN115277291A (en) | 2022-11-01 |
| CN115277291B true CN115277291B (en) | 2023-07-18 |
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| CN116909197B (en) * | 2023-09-05 | 2024-01-05 | 江苏正泰泰杰赛智能科技有限公司 | MBUS signal conversion module and conversion method for multi-type water meter acquisition |
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| CN205068755U (en) * | 2015-08-19 | 2016-03-02 | 积成电子股份有限公司 | A MBUS circuit for host computer end |
| CN111884646A (en) * | 2020-08-13 | 2020-11-03 | 四川广安爱众股份有限公司 | Intelligent M-BUS host circuit with photoelectric isolation function and control method |
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| AUPQ480199A0 (en) * | 1999-12-22 | 2000-02-03 | AGL Consultancy Pty. Limited | Timed window ultrasonic gas meter with nose cone |
| WO2014101630A1 (en) * | 2012-12-28 | 2014-07-03 | 华立仪表集团股份有限公司 | Near-infrared reading device and ammeter |
| CN105784202A (en) * | 2014-12-19 | 2016-07-20 | 天津市中天电子发展有限公司 | Low-power consumption intelligent ultrasonic heat meter |
| CN105139628B (en) * | 2015-08-19 | 2019-02-15 | 积成电子股份有限公司 | A kind of MBUS circuit for host side |
| CN204856875U (en) * | 2015-08-23 | 2015-12-09 | 吉首大学 | MBUS host computer of connecting LAN through WIFI |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN205068755U (en) * | 2015-08-19 | 2016-03-02 | 积成电子股份有限公司 | A MBUS circuit for host computer end |
| CN111884646A (en) * | 2020-08-13 | 2020-11-03 | 四川广安爱众股份有限公司 | Intelligent M-BUS host circuit with photoelectric isolation function and control method |
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