CN202794334U - Wide-range direct current standard electric energy meter - Google Patents

Wide-range direct current standard electric energy meter Download PDF

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Publication number
CN202794334U
CN202794334U CN201220483250.1U CN201220483250U CN202794334U CN 202794334 U CN202794334 U CN 202794334U CN 201220483250 U CN201220483250 U CN 201220483250U CN 202794334 U CN202794334 U CN 202794334U
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China
Prior art keywords
current
electric energy
voltage
module
central processing
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Expired - Lifetime
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CN201220483250.1U
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Chinese (zh)
Inventor
余义宙
李长宣
黄晓明
曹磊
袁强明
周晓辉
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ZHENGZHOU SMS ELECTRIC CO Ltd
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ZHENGZHOU SMS ELECTRIC CO Ltd
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Abstract

The utility model discloses a wide-range direct current standard electric energy meter which comprises a sampling module, an analog to digital (A/D) conversion module, a central processing module and an electric energy pulse module, wherein the sampling module, the A/D conversion module, the central processing module and the electric energy pulse module are connected in sequence. The central processing module is respectively connected with a communication module and a display module and further comprises a power module, and the sampling module comprises a direct-current voltage sampling module and a direct-current current sampling module. The wide-range direct current standard electric energy meter performs high-speed sampling on voltage signals exerted on a voltage terminal and generates voltage digital signals through the direct-current voltage sampling module, performs high-speed sampling on current signals passing through a current terminal and generates current digital signals through a zero-flux current compared type direct-current current transformer, and generates standard electric energy and standard electric energy pulse through calculation of the central processing module, wherein the standard electric energy and the standard electric energy pulse are used by an error calculation unit in a direct-current calibration board. The wide-range direct current standard electric energy meter can support large voltage span and current span, supports high voltage and large current, and can verify various installation type direct-current electric energy meters or low-grade direct-current standard meters.

Description

A kind of wide-range direct current standard electric energy meter
Technical field
The utility model relates to a kind of standard electric energy meter, relates in particular to a kind of wide-range direct current standard electric energy meter.
Background technology
Electric energy meter can be divided into installing type electric energy meter and standard electric energy meter according to use occasion.The installing type electric energy meter is used for industry and civilian electric energy metrical, throughout the year non-stop run.The installing type electric energy meter is as a kind of metering outfit, and its class of accuracy is lower than standard electric energy meter.Standard electric energy meter is a kind of standard of transmission of quantity value, and its class of accuracy is higher, generally uses in the laboratory, is used for calibrating installing type or the lower electric energy meter of accuracy.The principle of work of installing type electric energy meter and standard electric energy meter is substantially the same, just respectively gives priority to when design, and standard electric energy meter more lays particular emphasis on accuracy, and is provided with checking routine, can examine and determine easily and accurately tested electric energy meter.
At present, the electric energy meter overwhelming majority of widely applying on the market is AC energy meter, and the standard electric energy meter that verification is used also all is to exchange standard electric energy meter basically.Along with the needs of the direct current energy meterings such as the development of solar energy generation technology, electric vehicle charging power technology and direct current cabinet, electrolytic metallurgy, the application of direct current installing type electric energy meter is more and more extensive.Because being simple and easy to the voltage and current mutual inductor of usefulness, can not use in direct current, therefore direct current installing type electric energy meter generally adopts direct access, there are larger voltage span and electric current span, especially for high-voltage large current, its direct current energy meter calibration equipment of verification and direct current standard electric energy meter also must be supported larger voltage span and electric current span, and support high voltage and large electric current.And existing direct current standard electric energy meter can't satisfy above requirement.
The utility model content
The purpose of this utility model provides a kind of wide-range direct current standard electric energy meter, can support larger voltage span and electric current span, and supports high voltage and large electric current input, can carry out verification to various installing type direct current energy meters and inferior grade direct current standard scale.
The utility model adopts following technical proposals:
A kind of wide-range direct current standard electric energy meter, comprise the sampling module, A/D modular converter, central processing module and the electrical energy pulse module that connect successively, central processing module is connecting communication module and display module respectively, also comprise power module, described sampling module comprises DC voltage sampling module and DC current sampling module.
Described DC current sampling module comprises electric current gear transfer relay and the DC current transformer that connects successively; the output terminal of DC current transformer connects the signal input part of A/D modular converter through accurate sample resistance; the signal output part of A/D modular converter connects the sampled signal input end of central processing module; DC current transformer also connects the bypass protection relay by electric current outrange detection alarm circuit; the output terminal of electric current outrange detection alarm circuit also connects the central processing module input end; the bypass protection relay connects respectively DC current transformer and line under-voltage holding circuit, and the electric current gear transfer relay control signal output terminal of central processing module connects electric current gear transfer relay.
Described DC current transformer adopts zero flux current comparison expression DC current transformer.
Described DC voltage sampling module comprises the accurate divider resistance string that connects successively, voltage gear transfer relay and high impedance follower amplifier, the output terminal of high impedance follower amplifier connects respectively the signal input part of voltage outrange detection alarm circuit and A/D modular converter, the signal output part of A/D modular converter connects the sampled signal input end of central processing module, the output terminal of voltage outrange detection alarm circuit connects the central processing module input end, be connected with voltage outrange clamping circuit between voltage gear transfer relay and the high impedance follower amplifier, the voltage gear transfer relay control signal output terminal of central processing module connects electric current gear transfer relay.
Described A/D modular converter comprises A/D conversion chip and voltage reference chip, and the A/D conversion chip adopts 16 4 road synchronized sampling A/D conversion chips.
Described communication module comprises RS232, RS485 and/or CAN communicating circuit.
Being provided with high speed photo coupling between described communication module and the central processing module isolates.
Described electrical energy pulse module comprises high speed photo coupling and digital drive chip.
Described power module comprises transformer, voltage stabilizing chip and super capacitor.
The utility model carries out high-speed sampling and produces voltage digital signal the voltage signal that is added in voltage terminal by the DC voltage sampling module, by zero flux current comparison expression DC current transformer the current signal of current flowing terminal is carried out high-speed sampling and generation current digital signal, through central processing module voltage digital signal and current digital signal are carried out computing, generation standard electric energy and standard electric energy impulse are for the error calculation unit in the direct current checking table, can support larger voltage span and electric current span, and support high voltage and large electric current, can carry out verification to various installing type direct current energy meters and inferior grade direct current standard scale, simple in structure, be easy to realize.
Description of drawings
Fig. 1 is theory diagram of the present utility model;
Fig. 2 is the theory diagram of DC current sampling module;
Fig. 3 is the theory diagram of DC voltage sampling module.
Embodiment
As shown in Figure 1, the utility model comprises sampling module, A/D modular converter, central processing module and the electrical energy pulse module that connects successively, central processing module is connecting communication module and display module respectively, also comprise power module, described sampling module comprises DC voltage sampling module and DC current sampling module.
As shown in Figure 2; the DC current sampling module comprises electric current gear transfer relay and the DC current transformer that connects successively; the output terminal of DC current transformer connects the signal input part of A/D modular converter through accurate sample resistance; the signal output part of A/D modular converter connects the sampled signal input end of central processing module; DC current transformer also connects the bypass protection relay by electric current outrange detection alarm circuit; the output terminal of electric current outrange detection alarm circuit also connects the central processing module input end; the bypass protection relay connects respectively DC current transformer and line under-voltage holding circuit, and the electric current gear transfer relay control signal output terminal of central processing module connects electric current gear transfer relay.DC current transformer adopts zero flux current comparison expression DC current transformer.
When carrying out current sample, the current signal of input is after electric current gear transfer relay is selected the zero former limit of the flux current comparison expression DC current transformer number of turn, secondary in zero flux current comparison expression DC current transformer produces the secondary current that is directly proportional with primary current, secondary current is sent into the A/D change-over circuit after accurate sample resistance converts voltage signal to, finish sampling process.
Zero flux current comparison expression DC current transformer drives the secondary coil electric current by the magnetic field difference that detects the generation of primary coil electric current and secondary coil electric current, primary coil will produce stronger remanent magnetism in magnetic core when input current outrange or secondary power supply disappearance, thereby affect measuring accuracy, when magnetic field is stronger, also damage easily the magnetic field detection element.Electric current outrange detection alarm circuit can detect the relatively output of zero flux current comparison expression DC current transformer; when relatively output surpasses limit value, send a signal to central processing module; and connection bypass protection relay; with DC current transformer former limit bypass, and then protection zero flux current comparison expression DC current transformer and inspection magnetic cell thereof.When central processing module receive that electric current outrange detection alarm circuit sends after relatively output surpasses the signal of limit value, the gearshift of control electric current gear transfer relay, until electric current outrange detection alarm circuit is no longer till the central processing module transmitted signal, illustrate that electric current gear transfer relay selected suitable relay gear this moment, guarantees accuracy of measurement.The line under-voltage holding circuit is for detection of power module, and the under-voltage or driving bypass protection relay when lacking of powering when power module is with DC current transformer former limit bypass.
As shown in Figure 3, the DC voltage sampling module comprises the accurate divider resistance string that connects successively, voltage gear transfer relay and high impedance follower amplifier, the output terminal of high impedance follower amplifier connects respectively the signal input part of voltage outrange detection alarm circuit and A/D modular converter, the signal output part of A/D modular converter connects the sampled signal input end of central processing module, the output terminal of voltage outrange detection alarm circuit connects the central processing module input end, be connected with voltage outrange clamping circuit between voltage gear transfer relay and the high impedance follower amplifier, the voltage gear transfer relay control signal output terminal of central processing module connects electric current gear transfer relay.
When carrying out voltage sample; the voltage signal of input is through accurate divider resistance string; select behind the suitable intrinsic standoff ratio voltage signal dividing potential drop with input by voltage gear transfer relay; then send into the high impedance signal that high impedance follower amplifier obtains dividing potential drop and convert the Low ESR signal to, voltage outrange clamping circuit will carry out clamper with protection follower amplifier and A/D change-over circuit above the voltage signal of setting range.Voltage signal is at first by default relay gear input, voltage outrange detection alarm circuit can detect voltage signal, if voltage signal belongs to the outrange voltage signal then sends a signal to central processing module, central processing module carries out the gear hand-off process by voltage gear transfer relay, until voltage outrange detection alarm circuit no longer sends the outrange voltage signal to central processing module, suitable relay gear has been chosen in expression at this moment, high impedance follower amplifier is sent into signal the A/D change-over circuit again, finishes the voltage sample process.
The A/D modular converter comprises A/D conversion chip and voltage reference chip.The A/D conversion chip adopts 16 4 road synchronized sampling A/D conversion chips that design for electric energy metrical specially, this A/D conversion chip can convert the current signal of the voltage signal of DC voltage sampling module collection, the collection of DC current sampling module to the digital signal of 16 of two-way and send into central processing module, the voltage reference chip provides the conversion benchmark for the A/D conversion chip, finishes sampling process.
Central processing module is used for receiving voltage digital signal and the current digital signal that the conversion of A/D conversion chip comes, and obtain instantaneous power after multiplying each other in real time, then instantaneous power was carried out obtaining measuring electric energy behind the integration to the time, cut apart by the metering electric energy again and produce the high-frequency electrical energy pulse, the high-frequency electrical energy pulse obtains the low-frequency electrical energy pulse through frequency division of software, the while central processing module carries out smoothing processing with voltage digital signal and obtains the voltage digital amount, the current digital amount will be obtained after the current digital signal smoothing processing, power signal is carried out obtaining the power digital quantity after the smoothing processing, and these digital quantities can be by communication module for upper machine-readable getting.
Communication module comprises and RS232, RS485 and/or the CAN communicating circuit of upper machine communication, is provided with high speed photo coupling between each communication module and the central processing module and isolates.
The electrical energy pulse module comprises high speed photo coupling and digital drive chip, the electrical energy pulse that central processing module produces can be delivered to the direct current checking table.
Power module comprises transformer, voltage stabilizing chip and super capacitor, and transformer can convert the 220V electric main to the low-voltage AC that needs, and gives each module to use behind rectifying and voltage-stabilizing; The electric energy that super capacitor stores drives the bypass protection relay with zero flux current comparison expression DC current transformer primary coil bypass behind the 220V power cut-off, to protect zero flux current comparison expression DC current transformer.
During use, the standard electric energy impulse of wide-range direct current standard electric energy meter described in the utility model output and given simultaneously error calculation unit in the direct current checking table by the electrical energy pulse of alignment stream electric energy meter, error calculation unit to two-way pulse count comparison, thereby calculate by alignment stream electric energy meter error.When test host computer of having good luck is read the standard electric energy from wide-range direct current standard electric energy meter described in the utility model, and from being compared by the electric energy of reading the alignment stream electric energy meter, thereby calculate by the error of having good luck of alignment stream electric energy meter.
A/D conversion chip described in the utility model, voltage reference chip, high speed photo coupling, digital drive chip, voltage stabilizing chip and super capacitor all belong to ripe prior art, do not repeat them here.
The utility model passes through the high voltage of wide-range, sampling with high precision and the computing of heavy DC electricity, realization is to the high-precision measuring of direct current energy, and be provided with the output of the needed low-and high-frequency electrical energy pulse of standard electric energy meter, for the verification of direct current energy meter provides Transfer Standards.Wide-range direct current standard electric energy meter voltage range described in the utility model is 24V-1200V, and current range is 1mA-720A, and class of accuracy is 0.05%.

Claims (9)

1. wide-range direct current standard electric energy meter, it is characterized in that: comprise the sampling module, A/D modular converter, central processing module and the electrical energy pulse module that connect successively, central processing module is connecting communication module and display module respectively, also comprise power module, described sampling module comprises DC voltage sampling module and DC current sampling module.
2. wide-range direct current standard electric energy meter according to claim 1; it is characterized in that: described DC current sampling module comprises electric current gear transfer relay and the DC current transformer that connects successively; the output terminal of DC current transformer connects the signal input part of A/D modular converter through accurate sample resistance; the signal output part of A/D modular converter connects the sampled signal input end of central processing module; DC current transformer also connects the bypass protection relay by electric current outrange detection alarm circuit; the output terminal of electric current outrange detection alarm circuit also connects the central processing module input end; the bypass protection relay connects respectively DC current transformer and line under-voltage holding circuit, and the electric current gear transfer relay control signal output terminal of central processing module connects electric current gear transfer relay.
3. wide-range direct current standard electric energy meter according to claim 2 is characterized in that: described DC current transformer employing zero flux current comparison expression DC current transformer.
4. wide-range direct current standard electric energy meter according to claim 3, it is characterized in that: described DC voltage sampling module comprises the accurate divider resistance string that connects successively, voltage gear transfer relay and high impedance follower amplifier, the output terminal of high impedance follower amplifier connects respectively the signal input part of voltage outrange detection alarm circuit and A/D modular converter, the signal output part of A/D modular converter connects the sampled signal input end of central processing module, the output terminal of voltage outrange detection alarm circuit connects the central processing module input end, be connected with voltage outrange clamping circuit between voltage gear transfer relay and the high impedance follower amplifier, the voltage gear transfer relay control signal output terminal of central processing module connects electric current gear transfer relay.
5. wide-range direct current standard electric energy meter according to claim 4, it is characterized in that: described A/D modular converter comprises A/D conversion chip and voltage reference chip, the A/D conversion chip adopts 16 4 road synchronized sampling A/D conversion chips.
6. wide-range direct current standard electric energy meter according to claim 5, it is characterized in that: described communication module comprises RS232, RS485 and/or CAN communicating circuit.
7. wide-range direct current standard electric energy meter according to claim 6 is characterized in that: be provided with high speed photo coupling between described communication module and the central processing module and isolate.
8. wide-range direct current standard electric energy meter according to claim 7, it is characterized in that: described electrical energy pulse module comprises high speed photo coupling and digital drive chip.
9. wide-range direct current standard electric energy meter according to claim 8, it is characterized in that: described power module comprises transformer, voltage stabilizing chip and super capacitor.
CN201220483250.1U 2012-09-21 2012-09-21 Wide-range direct current standard electric energy meter Expired - Lifetime CN202794334U (en)

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Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103326311A (en) * 2013-05-15 2013-09-25 西北农林科技大学 Portable direct-current monitoring protector
CN103364614A (en) * 2013-07-14 2013-10-23 中国科学院近代物理研究所 Self-adaptive wide-range current and voltage conversion device
CN103543330A (en) * 2013-11-11 2014-01-29 博耳(宜兴)电力成套有限公司 High-precision circuit collection device
CN103604961A (en) * 2013-11-28 2014-02-26 保定久鼎保互电气有限公司 Non-linear load metering device
CN104698264A (en) * 2013-12-10 2015-06-10 英飞凌科技股份有限公司 Passive input filter with adjustable clamping for shunt measurements
CN105259532A (en) * 2015-11-26 2016-01-20 云南电网有限责任公司电力科学研究院 Electric vehicle charging pile DC electric energy meter calibration system
CN106019202A (en) * 2016-05-12 2016-10-12 国网天津市电力公司 Multi-channel digital standard electric energy meter
CN106324319A (en) * 2016-08-02 2017-01-11 许继集团有限公司 Direct current voltage and direct current signal sampling circuit
CN107290705A (en) * 2017-07-14 2017-10-24 国网天津市电力公司电力科学研究院 A kind of direct-current electric energy meter calibrating device
CN107315156A (en) * 2017-08-09 2017-11-03 浙江涵普电力科技有限公司 High-accuracy direct current standard electric energy meter
CN107328969A (en) * 2014-11-05 2017-11-07 江苏省电力公司常州供电公司 A kind of electric energy meter of measurable residual current
CN107422182A (en) * 2017-06-14 2017-12-01 珠海中慧微电子股份有限公司 Direct current energy meter
CN107529622A (en) * 2017-09-13 2018-01-02 浙江盛迪科技股份有限公司 A kind of three-phase high-voltage electric energy table verifying attachment
CN112649665A (en) * 2021-01-07 2021-04-13 云南电网有限责任公司电力科学研究院 Integrated high-voltage direct-current electric energy meter
CN113341218A (en) * 2021-07-08 2021-09-03 广东电网有限责任公司 Direct current electric energy meter with self-adaptive regulation of measuring range and control method thereof
CN113391104A (en) * 2021-05-25 2021-09-14 中国电力科学研究院有限公司 Dual-mode and direct access type direct current electric energy meter and electric energy metering method
CN116008655A (en) * 2023-02-13 2023-04-25 山东省计量科学研究院 Electric energy metering device for measuring bidirectional DC converter
CN116500536A (en) * 2023-04-14 2023-07-28 南京丹迪克电力仪表有限公司 Method for electric energy meter direct current and even harmonic influence test and alternating current-direct current electric energy meter testing device

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103326311A (en) * 2013-05-15 2013-09-25 西北农林科技大学 Portable direct-current monitoring protector
CN103326311B (en) * 2013-05-15 2015-09-16 西北农林科技大学 Portable DC monitoring and protecting device
CN103364614A (en) * 2013-07-14 2013-10-23 中国科学院近代物理研究所 Self-adaptive wide-range current and voltage conversion device
CN103364614B (en) * 2013-07-14 2015-10-28 中国科学院近代物理研究所 Self-adaptation wide-range current/voltage conversion equipment
CN103543330B (en) * 2013-11-11 2016-01-27 博耳(宜兴)电力成套有限公司 High-precision circuit collection device
CN103543330A (en) * 2013-11-11 2014-01-29 博耳(宜兴)电力成套有限公司 High-precision circuit collection device
CN103604961A (en) * 2013-11-28 2014-02-26 保定久鼎保互电气有限公司 Non-linear load metering device
CN103604961B (en) * 2013-11-28 2016-03-02 保定久鼎保互电气有限公司 A kind of measuring apparatus of nonlinear-load
US9632111B2 (en) 2013-12-10 2017-04-25 Infineon Technologies Ag Passive input filter with clamping for shunt measurements
CN104698264A (en) * 2013-12-10 2015-06-10 英飞凌科技股份有限公司 Passive input filter with adjustable clamping for shunt measurements
CN107328969A (en) * 2014-11-05 2017-11-07 江苏省电力公司常州供电公司 A kind of electric energy meter of measurable residual current
CN105259532A (en) * 2015-11-26 2016-01-20 云南电网有限责任公司电力科学研究院 Electric vehicle charging pile DC electric energy meter calibration system
CN106019202A (en) * 2016-05-12 2016-10-12 国网天津市电力公司 Multi-channel digital standard electric energy meter
CN106324319A (en) * 2016-08-02 2017-01-11 许继集团有限公司 Direct current voltage and direct current signal sampling circuit
CN107422182A (en) * 2017-06-14 2017-12-01 珠海中慧微电子股份有限公司 Direct current energy meter
CN107290705A (en) * 2017-07-14 2017-10-24 国网天津市电力公司电力科学研究院 A kind of direct-current electric energy meter calibrating device
CN107315156B (en) * 2017-08-09 2024-04-16 浙江涵普电力科技有限公司 High-precision direct-current standard electric energy meter
CN107315156A (en) * 2017-08-09 2017-11-03 浙江涵普电力科技有限公司 High-accuracy direct current standard electric energy meter
CN107529622A (en) * 2017-09-13 2018-01-02 浙江盛迪科技股份有限公司 A kind of three-phase high-voltage electric energy table verifying attachment
CN112649665A (en) * 2021-01-07 2021-04-13 云南电网有限责任公司电力科学研究院 Integrated high-voltage direct-current electric energy meter
CN113391104A (en) * 2021-05-25 2021-09-14 中国电力科学研究院有限公司 Dual-mode and direct access type direct current electric energy meter and electric energy metering method
CN113341218A (en) * 2021-07-08 2021-09-03 广东电网有限责任公司 Direct current electric energy meter with self-adaptive regulation of measuring range and control method thereof
CN113341218B (en) * 2021-07-08 2022-09-27 广东电网有限责任公司 Direct current electric energy meter with self-adaptive regulation of measuring range and control method thereof
CN116008655A (en) * 2023-02-13 2023-04-25 山东省计量科学研究院 Electric energy metering device for measuring bidirectional DC converter
CN116500536A (en) * 2023-04-14 2023-07-28 南京丹迪克电力仪表有限公司 Method for electric energy meter direct current and even harmonic influence test and alternating current-direct current electric energy meter testing device

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