阅读说明：本技术 一种数据采集记录仪的交直流电压采集电路 (AC/DC voltage acquisition circuit of data acquisition recorder ) 是由 邱小波 于亚雄 杨铭轩 黄中杰 梁彦 茹浩 高钥颖 严汉秋 徐开炜 梁业全 徐陶 于 2019-09-23 设计创作，主要内容包括：本发明公开了一种数据采集记录仪的交直流电压采集电路,属于电子硬件设备的电路结构的技术领域。本发明的数据采集记录仪的交直流电压采集电路,包括电路保护结构、信号处理结构和参考电压结构；三者相互并联共地。电路保护结构包括输入电压保护模块、第一电压衰减器、过压保护模块和第二电压衰减器；信号处理结构包括共模噪声抑制模块、隔离放大器、差分转单端模块、缓冲放大器、模-数转换器；参考电压结构为一个带隙二极管。使用本数据采集记录仪的交直流电压采集电路,相比现有录波仪的采集电路,电路结构相对简单且材料成本低廉,带多级保护和隔离功能,大大提高了数据采集记录仪进行信号数据采集的安全性,适用于在生产一线快速部署。(The invention discloses an alternating current and direct current voltage acquisition circuit of a data acquisition recorder, and belongs to the technical field of circuit structures of electronic hardware equipment. The alternating current and direct current voltage acquisition circuit of the data acquisition recorder comprises a circuit protection structure, a signal processing structure and a reference voltage structure; the three are mutually connected in parallel and are grounded. The circuit protection structure comprises an input voltage protection module, a first voltage attenuator, an overvoltage protection module and a second voltage attenuator; the signal processing structure comprises a common mode noise suppression module, an isolation amplifier, a differential-to-single end conversion module, a buffer amplifier and an analog-to-digital converter; the reference voltage structure is a bandgap diode. Compared with the acquisition circuit of the existing wave recorder, the alternating current and direct current voltage acquisition circuit using the data acquisition recorder has the advantages of relatively simple circuit structure, low material cost, multi-stage protection and isolation functions, greatly improved safety of signal data acquisition of the data acquisition recorder, and suitability for quick deployment in the production line.)

1. The utility model provides an alternating current and direct current voltage acquisition circuit of data acquisition record appearance which characterized in that: the circuit protection structure comprises a circuit protection structure, a signal processing structure and a reference voltage structure; the circuit protection structure and the signal processing structure share a grounding wire, and the reference voltage structure is used for supplying power to the signal processing structure; the circuit protection structure is used for preventing the signal processing structure from being over-voltage, and the reference voltage structure provides reference voltage for the signal processing structure.

2. An ac/dc voltage acquisition circuit of a data acquisition recorder as claimed in claim 1, wherein: the circuit protection structure comprises an input voltage protection module, a first voltage attenuator, an overvoltage protection module and a second voltage attenuator; the signal processing structure comprises a common mode noise suppression module, an isolation amplifier, a differential-to-single-ended module, a buffer amplifier and an analog-to-digital converter.

3. An ac/dc voltage acquisition circuit of a data acquisition recorder as claimed in claim 2, wherein: the input voltage protection module is connected with the first attenuator in series; the overvoltage protection module is connected with the first attenuator in parallel; the first voltage attenuator is connected in parallel with the common mode noise suppression module; the common mode noise suppression module is connected with the isolation amplifier in series; the isolation amplifier is connected in series with the differential-to-single-ended module; the differential-to-single-ended module is connected in series with the second voltage attenuator; the second voltage attenuator is connected with the buffer amplifier in series; the buffer amplifier is connected with the analog-digital converter in series; the analog-to-digital converter is connected in parallel with the reference voltage structure.

4. An ac/dc voltage acquisition circuit of a data acquisition recorder as claimed in claim 3, wherein: the input voltage protection module is a protective tube and a piezoresistor which are sequentially connected in series; the input voltage protection module is connected with an external input signal in series; one end of the protective tube is connected with an external input signal, and the other end of the protective tube is connected with one end of the piezoresistor; the other end of the piezoresistor is grounded.

5. An ac/dc voltage acquisition circuit of the data acquisition recorder according to claim 4, wherein: the first voltage attenuator and the second voltage attenuator are respectively two resistors connected in series; the first series resistor of the first voltage attenuator is connected with the joint of the protective tube and the piezoresistor, and the second series resistor is grounded; the first series resistor of the second voltage attenuator is connected with the output end of the differential-to-single-ended module, and the second series resistor is grounded.

6. An ac/dc voltage acquisition circuit of a data acquisition recorder as claimed in claim 5, wherein: the overvoltage protection module is a bidirectional voltage stabilizing diode; the bidirectional voltage stabilizing diode is connected with the second series resistor of the first voltage attenuator in parallel.

7. An ac/dc voltage acquisition circuit for a data acquisition recorder as claimed in claim 6, wherein: the common mode noise suppression module consists of two inductors; one end of the first inductor is connected with the joint of the two resistors of the first voltage attenuator, and the other end of the first inductor is connected with one input end of the isolation amplifier; one end of the second inductor is grounded, and the other end of the second inductor is connected with the other input end of the isolation amplifier; two input ends of the differential-to-single-ended module are respectively connected with two output ends of the isolation amplifier; the input end of the buffer amplifier is connected with the joint of the two resistors of the second voltage attenuator, and the output end of the buffer amplifier is connected with the signal input end of the analog-digital converter; the voltage input end of the analog-digital converter is connected with the reference voltage structure.

8. An ac/dc voltage acquisition circuit for a data acquisition recorder as claimed in claim 7, wherein: the analog-to-digital converter is a twelve bit analog-to-digital converter.

9. An ac/dc voltage acquisition circuit for a data acquisition recorder as claimed in claim 8, wherein: the protective tube is a ceramic explosion-proof protective tube.

10. An ac/dc voltage acquisition circuit for a data acquisition recorder according to any one of claims 1-9, wherein: the reference voltage structure is a band gap diode; the cathode of the band-gap diode is grounded, and the anode of the band-gap diode is connected with an external power supply; the voltage input end of the twelve-bit analog-digital converter is connected with the anode of the band-gap diode.

Technical Field

The invention relates to the technical field of electronic equipment hardware, in particular to a structure of an alternating current and direct current voltage acquisition circuit.

Background

The wave recorder is a device for recording electrical quantity or converting and recording different electrical quantities, can record data of different electrical quantities in real time, draw a curve in real time, and play back and analyze the curve according to needs. The signal acquisition circuit of the existing wave recorder is often provided with a complex control circuit, so that the wave recorder has the condition of very complex parameter setting in the use process, the knowledge level of personnel is high, the time consumed in the setting process is relatively long, and the wave recorder is not beneficial to rapid deployment and use of equipment in the production line. And the existing wave recorder has higher manufacturing cost, relatively complex circuit structure for collecting AC/DC voltage and higher maintenance difficulty.

Disclosure of Invention

In order to solve one or more problems in the background art, the invention provides a technical scheme of an alternating current and direct current voltage acquisition circuit of a data acquisition recorder, which is used for realizing access, acquisition, isolation and transformation of an external electrical quantity alternating current and direct current voltage signal.

The technical scheme of the invention is as follows:

an alternating current and direct current voltage acquisition circuit of a data acquisition recorder comprises a circuit protection structure, a signal processing structure and a reference voltage structure; the circuit protection structure and the signal processing structure share a grounding wire, and the reference voltage structure is used for supplying power to the signal processing structure; the circuit protection structure is used for preventing the signal processing structure from being over-voltage, and the reference voltage structure provides reference voltage for the signal processing structure. The overvoltage and short-circuit protection circuit has the advantages that overvoltage and short-circuit protection is carried out on the signal processing structure by the circuit protection structure, and the working voltage stability of the signal processing structure is guaranteed by the reference voltage structure.

Furthermore, the circuit protection structure comprises an input voltage protection module, a first voltage attenuator, an overvoltage protection module and a second voltage attenuator; the signal processing structure comprises a common mode noise suppression module, an isolation amplifier, a differential-to-single end conversion module, a buffer amplifier and an analog-to-digital converter. The effect is that the components in series-parallel connection mutually execute respective functions.

Further, the input voltage protection module is connected with the first attenuator in series; the overvoltage protection module is connected with the first attenuator in parallel; the first voltage attenuator is connected in parallel with the common mode noise suppression module; the common mode noise suppression module is connected with the isolation amplifier in series; the isolation amplifier is connected in series with the differential-to-single-ended module; the differential-to-single-ended module is connected in series with the second voltage attenuator; the second voltage attenuator is connected with the buffer amplifier in series; the buffer amplifier is connected with the analog-digital converter in series; the analog-to-digital converter is connected in parallel with the reference voltage structure. The effect is that each component constitutes a complete structure to perform the respective corresponding function.

Further, the input voltage protection module is a protective tube and a piezoresistor which are sequentially connected in series; the input voltage protection module is connected with an external input signal in series; one end of the protective tube is connected with an external input signal, and the other end of the protective tube is connected with one end of the piezoresistor; the other end of the piezoresistor is grounded. The voltage-sensitive resistor has the advantages that when the voltage of the collected signal exceeds the voltage-sensitive resistor threshold value, the voltage-sensitive resistor is broken down by the voltage of the collected signal, and the fuse tube is fused to protect a post-stage circuit.

Furthermore, the first voltage attenuator and the second voltage attenuator are respectively two resistors connected in series; the first series resistor of the first voltage attenuator is connected with the joint of the protective tube and the piezoresistor, and the second series resistor is grounded; the first series resistor of the second voltage attenuator is connected with the output end of the differential-to-single-ended module, and the second series resistor is grounded. The voltage stabilizing circuit has the effects that the voltage is reduced step by step, and the voltage of a post-stage circuit is ensured to be stabilized within a safety range.

Further, the overvoltage protection module is a bidirectional voltage regulator diode (tvs tube); the bidirectional voltage stabilizing diode is connected with the second series resistor of the first voltage attenuator in parallel. The voltage attenuator has the advantages that the voltage is clamped at a set value rapidly under the condition that the first voltage attenuator is invalid, and overvoltage of a post-stage circuit is prevented.

Furthermore, the common mode noise suppression module is composed of two inductors, one end of the first inductor is connected to the connection position of the two resistors of the first voltage attenuator, and the other end of the first inductor is connected to one input end of the isolation amplifier; one end of the second inductor is grounded, and the other end of the second inductor is connected with the other input end of the isolation amplifier; two input ends of the differential-to-single-ended module are respectively connected with two output ends of the isolation amplifier; the input end of the buffer amplifier is connected with the joint of the two resistors of the second voltage attenuator, and the output end of the buffer amplifier is connected with the signal input end of the analog-digital converter; the voltage input end of the analog-digital converter is connected with the reference voltage structure. The common mode noise suppression circuit has the advantages that the common mode noise suppression module can remove common mode noise of collected signals, the isolation amplifier carries out isolation amplification on the noise-reduced signals, the amplitude of the collected signals is improved, and meanwhile the safety of a post-stage circuit is guaranteed. The differential-to-single-ended module converts the differential signal into a single-ended signal, and ensures that the analog-to-digital converter identifies and reads the signal. The buffer amplifier performs impedance transformation to ensure the accuracy of the signal collected by measurement.

Further, the analog-to-digital converter is a twelve bit analog-to-digital converter. The effect is that reasonable analog signal sampling and digital signal coding and decoding capabilities are provided.

Further, the protective tube is a ceramic explosion-proof protective tube. The ceramic explosion-proof fuse has the advantages that quartz sand is filled in the ceramic explosion-proof fuse for arc extinction, the structure is firm, and damage to a circuit board can be effectively prevented.

Further, the reference voltage structure is a bandgap diode; the cathode of the band-gap diode is grounded, and the anode of the band-gap diode is connected with an external power supply; the voltage input end of the twelve-bit analog-digital converter is connected with the anode of the band-gap diode. The method has the effect of ensuring the stability and the precision of the working voltage of the twelve-bit analog-digital converter.

Compared with the prior art, the technical scheme of the invention has the beneficial effects that:

compared with the acquisition circuit of the existing wave recorder, the alternating current and direct current voltage acquisition circuit of the data acquisition recorder has the advantages of relatively simple circuit structure and low material cost, and realizes the functions of accessing, acquiring, isolating and converting the external electric quantity alternating current and direct current voltage signals. The system also has the functions of multi-stage protection and isolation, greatly improves the safety of signal data acquisition of the data acquisition recorder, and is suitable for quick deployment in the production line.

Drawings

FIG. 1 is a schematic diagram of the circuit configuration of the circuit of the present invention;

in fig. 1: the circuit comprises a protective tube 1, a piezoresistor 2, a voltage attenuator 3, a bidirectional TVS tube 4, a common mode noise suppression module 5, an isolation amplifier 6, a differential-to-single end module 7, a voltage attenuator 8, a buffer amplifier 9, an analog-to-digital converter 10 and a band gap diode 11.

Detailed Description

The drawings are for illustrative purposes only and are not to be construed as limiting the patent. For a better understanding of the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent actual product dimensions. It will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "designed," "connected," and the like are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, so to speak, as communicating between the two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The technical solution of the present invention is further described below with reference to the accompanying drawings and examples.

With reference to fig. 1, the connection relationship of the components is shown in the figure. The alternating current and direct current voltage acquisition circuit of the data acquisition recorder comprises a protective tube 1, a piezoresistor 2, a voltage attenuation module 3, a bidirectional TVS tube 4, a common mode noise suppression module 5, an isolation amplifier 6, a differential-to-single-ended module 7, a voltage attenuation module 8, a buffer amplifier 9, an analog-to-digital converter 10 and a band gap diode 11. The safety tube 1 is a ceramic explosion-proof safety tube, quartz sand is filled in the tube for arc extinction, the structure is firm, and the circuit board cannot be damaged by fire or high temperature; the analog-to-digital converter 10 is a twelve-bit analog-to-digital converter and can perform reasonable analog signal sampling and digital signal encoding and decoding on the acquired signals.

In the embodiment, one end of the protective tube 1 is connected with an input signal to be acquired from the outside, and the other end is connected with one end of the piezoresistor 2; the other end of the varistor 2 is connected to ground. The voltage attenuator 3 is two resistors connected in series; the first series resistor of the voltage attenuator 3 is connected with the connection position of the protective tube and the piezoresistor, and the second series resistor is grounded. The bidirectional TVS tube 4 is connected in parallel with the second series resistor of the voltage attenuator 3. The common mode noise suppression module 5 is composed of two inductors, one end of the first inductor is connected with the connection position of two resistors of the voltage attenuator 3, and the other end of the first inductor is connected with one input end of the isolation amplifier 6; one end of the second inductor is grounded, and the other end is connected to the other input end of the isolation amplifier 6. Two input ends of the differential-to-single-ended module 7 are respectively connected with two output ends of the isolation amplifier 6. The first series resistor of the voltage attenuator 8 is connected with the output end of the differential-to-single-ended module 7, and the second series resistor is grounded. The input end of the buffer amplifier 9 is connected to the connection of the two resistors of the voltage attenuator 8, and the output end of the buffer amplifier 9 is connected to the signal input end of the analog-digital converter 10. The voltage input terminal of the analog-to-digital converter 10 is connected to a bandgap diode 11. The cathode of the band-gap diode 11 is grounded, and the anode is connected with an external power supply; the voltage input of the analog-to-digital converter 10 is connected to the anode of a bandgap diode 11.

Compared with the acquisition circuit of the existing wave recorder, the acquisition circuit has the advantages of relatively simple circuit structure and low material cost of components, and realizes the functions of accessing, acquiring, isolating and converting the alternating-current and direct-current voltage signals of the external electric quantity. The system also has the functions of multi-stage protection and isolation, greatly improves the safety of signal data acquisition of the data acquisition recorder, and is suitable for quick deployment in the production line.

In the above embodiments, the alternating current and direct current voltage acquisition circuit of the data acquisition recorder simply changes the relevant parameters of the components, or uses other types of components with the same functions to replace them, which is only a routine replacement of the present embodiment, and does not have substantial changes and advances, and also falls within the scope set forth in the claims of the present technical solution.

Finally, the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all of them should be covered in the claims of the present invention.