CN106707009B - Wide-range high-precision current statistical circuit - Google Patents

Wide-range high-precision current statistical circuit Download PDF

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Publication number
CN106707009B
CN106707009B CN201611253115.7A CN201611253115A CN106707009B CN 106707009 B CN106707009 B CN 106707009B CN 201611253115 A CN201611253115 A CN 201611253115A CN 106707009 B CN106707009 B CN 106707009B
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resistor
integrator
operational amplifier
module
output end
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CN106707009A (en
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王春勇
沈翔
严伟
李振华
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Nanjing University of Science and Technology
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Nanjing University of Science and Technology
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
    • G01R15/08—Circuits for altering the measuring range

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Current Or Voltage (AREA)
  • Analogue/Digital Conversion (AREA)

Abstract

The invention discloses a wide-range high-precision current statistical circuit which comprises a multi-channel integrator, a pulse generator, a single chip microcomputer STM32 and an A/D module, wherein the output end of the integrator is divided into two paths, one path of output is connected with the input end of the pulse generator, the other path of output is connected with the input end of the A/D module, and the output end of the A/D module is connected with a single chip microcomputer STM 32; the output end of the pulse generator is connected with a GPIO interface of the singlechip STM 32; and a GPIO interface of the singlechip STM32 is connected with a bleeder switch of the integrator. The current detection circuit has the advantages of accurate counting to decimal places, wide range, high precision and the like, and provides a novel method and a novel approach for detecting wide-range weak current signals.

Description

Wide-range high-precision current statistical circuit
Technical Field
The invention relates to the technical field of weak current front-end reading circuits, in particular to a wide-range high-precision current statistical circuit.
Background
The existing current detection is generally based on a charge balance principle, a circuit integrates input current and then compares the integrated input current with standard discretization electric quantity, and a timer controls a switch to act to realize charge balance, so that a pulse signal with frequency in direct proportion to the input current is obtained. The integration type charge balance conversion principle can continuously measure the input signal, and the problem of information loss caused by discrete sampling does not exist. However, for the detection of weak current, the traditional circuit cannot complete the detection with wide range and high precision.
Therefore, a new current statistic circuit is needed to solve the above problems.
Disclosure of Invention
The invention aims to provide a wide-range and high-precision current statistical circuit aiming at the problems of insufficient range and insufficient precision in the existing current statistical circuit.
In order to achieve the above purpose, the wide-range high-precision current statistical circuit of the invention can adopt the following technical scheme:
wide-range high-precision current statistical circuitComprising an input current signal IinThe output end of the integrator is divided into two paths, one path of output is connected with the input end of the pulse generator, the other path of output is connected with the input end of the A/D module, and the output end of the A/D module is connected with the single chip microcomputer STM 32; the output end of the pulse generator is connected with a GPIO interface of the singlechip STM 32; and a GPIO interface of the singlechip STM32 is connected with a bleeder switch of the integrator.
The integrator is formed by connecting an operational amplifier A1, an integrating ceramic chip capacitor C1, a discharge protection resistor R1 and a bleeder switch S, and the inverting input end of the operational amplifier A1 is connected with an input circuit signal IinConnecting; the non-inverting input terminal of the operational amplifier A1 is connected with the ground; the inverting input end of the operational amplifier A1 is connected with one end of the integrating ceramic chip capacitor C1; the output end of the operational amplifier A1 is connected with the other end of the integrating ceramic chip capacitor C1; the inverting input end of the operational amplifier A1 is connected with one end of a discharge protection resistor R1; the other end of the discharge protection resistor R1 is connected with one end of the bleeder switch S; the output end of the operational amplifier A1 is connected with the other end of the bleeder switch S; the accumulated discharge protection resistor R1, the bleeder switch S and the sub-ceramic chip capacitor C1 form a parallel circuit; the control end of the bleeder switch S is connected with a GPIO interface in the singlechip STM 32; the output end of the operational amplifier A1 is divided into two paths, one path is connected with the input end of the A/D module, and the other path is connected with the pulse generator.
The pulse generator is formed by connecting a voltage comparator A2, resistors R2, R3, R4 and R5, wherein the inverting input end of the voltage comparator A2 is connected with a resistor R2, the other end of the resistor R2 is connected with the output of the integrator, the non-inverting input end of the voltage comparator A2 is connected with resistors R3 and R4, the other end of the resistor R3 is connected with the ground, and the other end of the resistor R4 is connected with the output end of the voltage comparator A2; the output end of the voltage comparator A2 is connected with a resistor R5, and the other end R5 of the resistor is connected with 3.3V voltage; the output end of the voltage comparator A2 is connected with the GPIO interface of the singlechip STM 32.
The A/D module adopts an AD7705 high-precision AD module.
The single chip microcomputer STM32 controls the release switch of the integrator to release through the pulse generated by the pulse generator. Meanwhile, when the integration time reaches the preset time, the single chip microcomputer STM32 reads the voltage value of the capacitor C1 of the integration ceramic chip in the current integrator through the A/D module and performs calculation processing with the pulse value in the internal counter to obtain a high-precision current energy statistical value in unit time.
Compared with the prior art, the invention has the following remarkable advantages:
1. the invention carries out statistical averaging on the current signals within a certain time through the integrator, has wide measuring range compared with the traditional technology, improves the linear error of wide-range current signal processing, and ensures the accuracy of data.
2. Compared with the traditional technology of counting the number of pulses, the invention has the advantages that the A/D sampling module is added in the integrator, the pulse number counting precision is accurate to the decimal place of the number of pulses, and the data precision is higher.
Drawings
Fig. 1 is a schematic diagram of the circuit principle of the present invention.
Fig. 2 is a circuit diagram of an integrator embodiment of the present invention.
Fig. 3 is a circuit diagram showing a specific circuit of the pulse generator of the present invention.
FIG. 4 is a core chip of the A/D module of the present invention.
Detailed Description
The invention is described in further detail below with reference to specific embodiments and with reference to the attached drawings.
As shown in FIG. 1, the present invention relates to a wide-range high-precision current statistic circuit, which comprises an input current signal IinThe output end of the integrator is divided into two paths, one path of output is connected with the input end of the pulse generator, the other path of output is connected with the input end of the A/D module, and the output end of the A/D module is connected with the single chip microcomputer STM 32; the output end of the pulse generator is connected with a GPIO interface of the singlechip STM 32; and a GPIO interface of the singlechip STM32 is connected with a bleeder switch of the integrator.
As shown in FIG. 2, the integrator is formed by connecting an operational amplifier A1, an integrating ceramic chip capacitor C1, a discharge protection resistor R1 and a bleeder switch S, wherein the inverting input end of the operational amplifier A1 is connected with an input circuit signal IinConnecting; positive of operational amplifier A1The phase input end is connected with the ground; the inverting input end of the operational amplifier A1 is connected with one end of the integrating ceramic chip capacitor C1; the output end of the operational amplifier A1 is connected with the other end of the integrating ceramic chip capacitor C1; the inverting input end of the operational amplifier A1 is connected with one end of a discharge protection resistor R1; the other end of the discharge protection resistor R1 is connected with one end of the bleeder switch S; the output end of the operational amplifier A1 is connected with the other end of the bleeder switch S; the accumulated discharge protection resistor R1, the bleeder switch S and the sub-ceramic chip capacitor C1 form a parallel circuit; the control end of the bleeder switch S is connected with a GPIO interface in the singlechip STM 32; the output end of the operational amplifier A1 is divided into two paths, one path is connected with the input end of the A/D module, and the other path is connected with the pulse generator.
As shown in fig. 3, the pulse generator is formed by connecting a voltage comparator a2, resistors R2, R3, R4 and R5, wherein the inverting input terminal of the voltage comparator a2 is connected with the resistor R2, the other end of the resistor R2 is connected with the output of the integrator, the non-inverting input terminal of the voltage comparator a2 is connected with the resistors R3 and R4, the other end of the resistor R3 is connected with ground, and the other end of the resistor R4 is connected with the output terminal of the voltage comparator a 2; the output end of the voltage comparator A2 is connected with a resistor R5, and the other end R5 of the resistor is connected with 3.3V voltage; the output end of the voltage comparator A2 is connected with the GPIO interface of the singlechip STM 32.
The A/D module adopts an AD7705 high-precision AD module.
The single chip microcomputer STM32 controls a drain switch of the integrator to drain through the pulse generated by the pulse generator; meanwhile, when the integration time reaches the preset time, the single chip microcomputer STM32 reads the voltage value of the capacitor C1 of the integration ceramic chip in the current integrator through the A/D module and performs calculation processing with the pulse value in the internal counter to obtain a high-precision current energy statistical value in unit time.
The invention relates to a wide-range high-precision current statistical circuit which is mainly composed of a high-precision integrator, a high-sensitivity voltage comparator, a single chip microcomputer STM32 and the like. When the pulse generator works, an input current signal forms a voltage signal on an integrating ceramic chip capacitor C1 in the integrator, the voltage signal is compared with a preset threshold value in the pulse generator, a pulse is generated when the voltage signal exceeds the threshold value, the voltage signal is transmitted to the single chip microcomputer STM32, and an internal counter counts. At the moment, the voltage of the capacitor C1 of an integrating ceramic chip in the integrator reaches a saturation state, the single chip microcomputer STM32 controls a drain switch of the integrator to drain, and the drain time is determined by C1 and R1. When the integration time reaches the preset time, the voltage of the current integrator integrating ceramic chip C1 capacitor output by the single chip microcomputer STM32 through the A/D module is processed and added with the count value in the internal counter to obtain the statistical data of the current signal in the time period. The repeated work completes the statistics of the high-precision wide-range current.
The wide-range high-precision current statistical circuit has the detection capability of current signals in 6 orders of magnitude ranges, and the A/D module is adopted in the integrator, so that the statistical precision of the number of pulses in unit time is improved, and the accuracy is improved to a decimal place, thereby improving the precision of the whole circuit and improving the linear error of wide-range current signal processing.

Claims (4)

1. The utility model provides a wide range high accuracy current statistics circuit which characterized in that: comprising a current signal I coupled to an inputinThe output end of the integrator is divided into two paths, one path of output is connected with the input end of the pulse generator, the other path of output is connected with the input end of the A/D module, and the output end of the A/D module is connected with the single chip microcomputer STM 32; the output end of the pulse generator is connected with a GPIO interface of the singlechip STM 32; the GPIO interface of the singlechip STM32 is connected with a bleeder switch of the integrator; the single chip microcomputer STM32 controls a drain switch of the integrator to drain through the pulse generated by the pulse generator; meanwhile, when the integration time reaches the preset time, the single chip microcomputer STM32 reads the voltage value of the capacitance C1 of the integration ceramic chip in the current integrator through the A/D module and performs calculation processing with the pulse value in the internal counter to obtain a high-precision current energy statistical value in unit time;
when the circuit works, an input current signal forms a voltage signal on an integrating ceramic chip capacitor C1 in the integrator, the voltage signal is compared with a preset threshold value in the pulse generator, a pulse is generated when the voltage signal exceeds the threshold value, the voltage signal is transmitted to the single chip microcomputer STM32, and an internal counter counts.
2. The wide range high accuracy current statistic circuit of claim 1 further characterized by: the integrator is formed by connecting an operational amplifier A1, an integrating ceramic chip capacitor C1, a discharge protection resistor R1 and a bleeder switch S, and the inverting input end of the operational amplifier A1 is connected with an input circuit signal IinConnecting; the non-inverting input terminal of the operational amplifier A1 is connected with the ground; the inverting input end of the operational amplifier A1 is connected with one end of the integrating ceramic chip capacitor C1; the output end of the operational amplifier A1 is connected with the other end of the integrating ceramic chip capacitor C1; the inverting input end of the operational amplifier A1 is connected with one end of a discharge protection resistor R1; the other end of the discharge protection resistor R1 is connected with one end of the bleeder switch S; the output end of the operational amplifier A1 is connected with the other end of the bleeder switch S; the accumulated discharge protection resistor R1, the bleeder switch S and the sub-ceramic chip capacitor C1 form a parallel circuit; the control end of the bleeder switch S is connected with a GPIO interface in the singlechip STM 32; the output end of the operational amplifier A1 is divided into two paths, one path is connected with the input end of the A/D module, and the other path is connected with the pulse generator.
3. The wide range high accuracy current statistic circuit of claim 1 further characterized by: the pulse generator is formed by connecting a voltage comparator A2, a first resistor R2, a second resistor R3, a third resistor R4 and a fourth resistor R5, wherein the inverting input end of the voltage comparator A2 is connected with the first resistor R2, the other end of the first resistor R2 is connected with the output of the integrator, the non-inverting input end of the voltage comparator A2 is connected with the second resistor R3 and the third resistor R4, the other end of the second resistor R3 is connected with the ground, and the other end of the third resistor R4 is connected with the output end of the voltage comparator A2; the output end of the voltage comparator A2 is connected with a fourth resistor R5, and the other end of the fourth resistor R5 is connected with 3.3V voltage; the output end of the voltage comparator A2 is connected with the GPIO interface of the singlechip STM 32.
4. The wide range high accuracy current statistic circuit of claim 1 further characterized by: the A/D module adopts an AD7705 high-precision AD module.
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CN107727914A (en) * 2017-09-29 2018-02-23 苏州涟漪信息科技有限公司 Signal measurement apparatus
WO2019109363A1 (en) * 2017-12-09 2019-06-13 Dongguan Bang Bang Tang Electronic Technologies Co., Ltd. Current sensor for biomedical measurements
CN114217122A (en) * 2021-11-23 2022-03-22 黑龙江省原子能研究院 Capacitance integral weak current measuring I/F conversion circuit
CN114839662A (en) * 2022-05-16 2022-08-02 哈尔滨工程大学 Wide-range gamma dosimeter

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD149964A2 (en) * 1979-05-29 1981-08-05 Alfred Frommhold ELECTRICITY / FREQUENCY CONVERTER AFTER THE INTEGRATION PROCESS
JP2000228300A (en) * 1999-02-04 2000-08-15 Sumitomo Heavy Ind Ltd Pulse beam current measuring device
CN2840052Y (en) * 2005-08-17 2006-11-22 北京双目佳测控技术有限责任公司 Electric energy meter and integration reduction-type current/voltage transducer thereof
CN101331402A (en) * 2005-12-15 2008-12-24 皇家飞利浦电子股份有限公司 Current measurement circuit and method
CN106053930A (en) * 2016-07-06 2016-10-26 西北核技术研究所 Switch-free weak-signal synchronization integration measurement apparatus and measurement method resisting random noise

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101226213B (en) * 2008-01-24 2010-06-09 南京埃斯顿自动控制技术有限公司 Method and apparatus for detecting electric machine phase current
CN104793045B (en) * 2015-04-23 2016-10-26 中国科学院近代物理研究所 A kind of wide-range current frequency converter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD149964A2 (en) * 1979-05-29 1981-08-05 Alfred Frommhold ELECTRICITY / FREQUENCY CONVERTER AFTER THE INTEGRATION PROCESS
JP2000228300A (en) * 1999-02-04 2000-08-15 Sumitomo Heavy Ind Ltd Pulse beam current measuring device
CN2840052Y (en) * 2005-08-17 2006-11-22 北京双目佳测控技术有限责任公司 Electric energy meter and integration reduction-type current/voltage transducer thereof
CN101331402A (en) * 2005-12-15 2008-12-24 皇家飞利浦电子股份有限公司 Current measurement circuit and method
CN106053930A (en) * 2016-07-06 2016-10-26 西北核技术研究所 Switch-free weak-signal synchronization integration measurement apparatus and measurement method resisting random noise

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Novel proportional-integral-resonant current controller for three phase PWM converters;Djordje Stojić等;《IEEE》;20161121;全文 *
弱电流测量中的电流一频率变换电路;董成富等;《电子元器件应用》;20040930;全文 *

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