CN108918939A - A kind of current measuring device that high-precision is easy to install - Google Patents
A kind of current measuring device that high-precision is easy to install Download PDFInfo
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- CN108918939A CN108918939A CN201810780809.9A CN201810780809A CN108918939A CN 108918939 A CN108918939 A CN 108918939A CN 201810780809 A CN201810780809 A CN 201810780809A CN 108918939 A CN108918939 A CN 108918939A
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- temperature
- rogowski coil
- resistance
- fixed value
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- 238000004891 communication Methods 0.000 claims abstract description 14
- 238000012545 processing Methods 0.000 claims abstract description 13
- 238000005259 measurement Methods 0.000 claims abstract description 7
- 239000000696 magnetic material Substances 0.000 claims description 13
- 239000000463 material Substances 0.000 claims description 5
- 238000009529 body temperature measurement Methods 0.000 claims description 3
- 238000009413 insulation Methods 0.000 claims 1
- 230000002093 peripheral effect Effects 0.000 claims 1
- 238000001514 detection method Methods 0.000 abstract description 2
- 230000010354 integration Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 5
- 230000009977 dual effect Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 241000218691 Cupressaceae Species 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Classifications
-
- 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
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
- G01R15/181—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers using coils without a magnetic core, e.g. Rogowski coils
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/44—Modifications of instruments for temperature compensation
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
The present invention relates to a kind of current measuring devices that high-precision is easy to install, belong to field of power detection.Including Rogowski coil module, temperature-measuring module, data processing module, display module, communication module, controllable resistor module, communication module, display module, controllable resistor module, Rogowski coil module and temperature-measuring module are connect with data processing module, Rogowski coil module includes Rogowski coil and integrating circuit, temperature-measuring module is used to measure the temperature of Rogowski coil, controllable resistor module includes adjustable resistance and fixed value resistance, fixed value resistance one end is connect with Rogowski coil, the connection of one end of the other end and adjustable resistance, the other end of adjustable resistance is connect with integrating circuit, temperature-measuring module uses nonequilibrium bridge structure bridge circuit.The present invention while the voltage of temperature collection measurement module and the voltage of Rogowski coil module concatenate an adjustable resistance in the integration circuit, are affected by temperature generated error to the resistance of Rogowski coil and compensate.
Description
Technical field
The present invention relates to a kind of current measuring devices that high-precision is easy to install, belong to technical field of electric power detection.
Technical background
Rogowski coil electronic current mutual inductor is also referred to as air core current transformer, and core is Rogowski coil (Rogowski
Coil, also known as air core coil) and magnetic potentiometer.Rogowski coil is measure traverse line is equably looped around to a sectional uniform non-magnetic
Property material skeleton on and constitute.Carrying out integral by using the voltage signal that a dedicated integrator exports coil can be with
Another ac voltage signal is obtained, this voltage signal can accurately reproduce the waveform of measured current signal.Due to not
Containing ferrimagnet, iron core saturation problem is not present in no hysteresis effect.Measurement range is wide, and same coil can be measured from several
Pacify the electric current to hundreds of kilo-amperes, the transient current containing big DC component can also be measured.
But Rogowski coil electronic current mutual inductor also has its limitation, as precision be affected by temperature it is larger.Measuring coil
Because the reason of heat, resistance value can change, the input terminal for measuring integrated circuit must be compensated by.Due to compensation and environment
Temperature is related, also related with size of current, and before microelectric technique does not occur, this work be cannot achieve.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of current measuring devices that high-precision is easy to install, by based on non-
The temperature of the thermosensitive resistance measurement conducting wire of balanced bridge learns the variation feelings of conductive line resistance values by the situation of change for the temperature surveyed
Condition is affected by temperature by concatenating a controllable resistor module before former integrating circuit by controlling its resistance value come compensating wire
Generated error.
The technical solution adopted by the present invention is that：A kind of current measuring device that high-precision is easy to install, including Rogowski coil mould
Block, temperature-measuring module, data processing module, display module, communication module, controllable resistor module, communication module, display mould
Block, controllable resistor module, Rogowski coil module and temperature-measuring module are connected with data processing module, Rogowski coil module
Including Rogowski coil and integrating circuit, temperature-measuring module is used to measure the temperature of Rogowski coil, and controllable resistor module includes can
Resistance and fixed value resistance, fixed value resistance one end is adjusted to connect with Rogowski coil, one end connection of the other end and adjustable resistance, adjustable electric
The other end of resistance is connect with integrating circuit, and temperature-measuring module uses nonequilibrium bridge structure bridge circuit, communication module and outer
Portion's device talk.
Specifically, the bridge circuit of the temperature-measuring module includes fixed value resistance R1、R2、R3With thermistor RX, fixed
It is worth resistance R1、R2One termination power cathode, fixed value resistance R1Another termination fixed value resistance R3One end, fixed value resistance R2It is another
One termination thermistor RXOne end, fixed value resistance R3The other end, thermistor RXAnother termination positive pole, temperature-sensitive electricity
Hinder RXIt is embedded in Rogowski coil, fixed value resistance R1、R3Connection midpoint and fixed value resistance R2With thermistor RXConnection midpoint it
Between voltage be U0。
Specifically, the Rogowski coil be open architecture, including coil body 1, non-magnetic material skeleton 2, shaft 3,
Insulating layer 4, lock 5, non-magnetic material skeleton 2 are two semicircular rings, coil body 1 uniformly around on non-magnetic material skeleton 2,
Insulating layer 4 is wrapped up outside coil body 1,2 one end of non-magnetic material skeleton of two semicircular rings passes through 5 connection of lock, the other end
It is rotatablely connected by shaft 3, lock 5 is fixed on insulating layer 4.
Specifically, resistance of the display module for the temperature data, adjustable resistance of the acquisition of displays temperature measurement module
Value.
Preferably, the data processing module includes single-chip microcontroller, fpga chip, SRAM, EPCS, and SRAM is used
CY7C006A, fpga chip use Spartan-6FPGA device.
The beneficial effects of the present invention are：The device acquires the voltage and Roche of coil temperature-measuring module simultaneously
The voltage of coil module concatenates an adjustable resistance in the integration circuit and is affected by temperature generated error to the resistance of coil
It compensates.
Detailed description of the invention
Fig. 1 is that overall structure of the present invention connects block diagram；
Fig. 2 is the structural schematic diagram of Rogowski coil of the present invention；
Fig. 3 is the circuit diagram of the bridge circuit of temperature-measuring module of the present invention；
Fig. 4 is the connection structure diagram of non-magnetic material skeleton in Rogowski coil of the present invention.
In figure respectively label for：1- coil；2- non-magnetic material skeleton；3- shaft；4- insulating layer；5- lock.
Specific embodiment
In the following with reference to the drawings and specific embodiments, the present invention is further illustrated.
Embodiment 1：As shown in Figs 1-4, a kind of current measuring device that high-precision is easy to install, including Rogowski coil module,
Temperature-measuring module, data processing module, display module, communication module, controllable resistor module, communication module, display module, can
Control resistive module, Rogowski coil module and temperature-measuring module are connected with data processing module, and Rogowski coil module includes
Rogowski coil and integrating circuit, temperature-measuring module are used to measure the temperature of Rogowski coil, and controllable resistor module includes adjustable electric
Resistance and fixed value resistance, fixed value resistance one end are connect with Rogowski coil, one end connection of the other end and adjustable resistance, adjustable resistance
The other end is connect with integrating circuit, and temperature-measuring module uses nonequilibrium bridge structure bridge circuit, and communication module is set with outside
Standby communication.For Rogowski coil module for acquiring current signal, temperature-measuring module is used to measure the temperature of Rogowski coil, at data
Module is managed to be used to the resistance value of adjustable resistance is adjusted, to Roche according to Rogowski coil module, the acquisition data of temperature-measuring module
Coil, which is affected by temperature, to be compensated.
Further, as shown in figure 3, the bridge circuit of the temperature-measuring module includes fixed value resistance R1、R2、R3With
Thermistor RX, fixed value resistance R1、R2One termination power cathode, fixed value resistance R1Another termination fixed value resistance R3One end,
Fixed value resistance R2Another termination thermistor RXOne end, fixed value resistance R3The other end, thermistor RXAnother termination electricity
Source anode, thermistor RXIt is embedded in Rogowski coil, fixed value resistance R1、R3Connection midpoint and fixed value resistance R2With thermistor RX
Connection midpoint between voltage be U0。
By thermistor RXIt is embedded in Rogowski coil, it is possible to accurately know temperature when Rogowski coil work,
Due to having between the resistance value and temperature of Rogowski coil conducting wire there are certain functional relation, its resistance can be calculated according to its temperature
Value, can carry out temperature-compensating to Rogowski coil according to the resistance value keeps final measurement more acurrate.
Further, as shown in Figure 2,4, the Rogowski coil is open architecture, including coil body 1, non magnetic material
Expect that skeleton 2, shaft 3, insulating layer 4, lock 5, non-magnetic material skeleton 2 are two semicircular rings, coil body 1 is uniformly around non-magnetic
Property material skeleton 2 on, insulating layer 4 is wrapped up outside coil body 1,2 one end of non-magnetic material skeleton of two semicircular rings passes through lock
5 connection of button, the other end are rotatablely connected by shaft 3, and lock 5 is fixed on insulating layer 4.Since Rogowski coil is open architecture,
It is easily installed.
Further, temperature data, adjustable resistance of the display module for the acquisition of displays temperature measurement module
Resistance value.
Further, the data processing module includes single-chip microcontroller, fpga chip, SRAM, EPCS, and the SRAM is
CY7C006A is the high speed twoport static state RAM of 16kb × 8 of Cypress company production, and access speed is less than 20ns.The device has
Real dual-port, can carry out data access simultaneously, and two ports have independent control signal wire, address wire and data
Line expands memory capacity and data width with can be convenient additionally by master/slave selection.Dual port RAM can be used for improving handling up for RAM
Rate is suitable for making in real-time data buffer storage.EPCS can not lose data in the case where power down.
Further, the FPGA is the Spartan-6FPGA device of Xilinx company, passes through Verilog HDL language
Speech is written and read control to dual port RAM.
The disposed of in its entirety process of data processing module is：Rogowski coil module output signal is the differential of Current versus time.
The circuit that the voltage signal of output is integrated by one, so that it may really restore input current.In order to compensate for temperature
It influences, with a fixed value resistance and an adjustable resistance series connection before integrating circuit, the resistance value of adjustable resistance is by Rogowski coil
The resistance value of conducting wire determines.
Due to having between the resistance value and temperature of Rogowski coil conducting wire there are certain functional relation, by being led to Rogowski coil
Line measures the resistance value of conducting wire at different temperatures, and obtained data are gone out between resistance and temperature by least square fitting
Equation.Further, the resistance value of conducting wire can be calculated by measuring the temperature of Rogowski coil conducting wire.There are R=f (T), Δ R
=R0- R, wherein R0, R is that temperature is t respectively0With the resistance value of conducting wire when t, Δ R is to need the resistance value compensated (by temperature shadow
Ring the error generated), the value of Δ R is transferred to single-chip microcontroller, by single-chip microcontroller controlling potential device to the adjustable control of resistance.
Fig. 3 is the schematic diagram of nonequilibrium bridge, when nonequilibrium bridge works, keeps R1、R2、R3For fixed value resistance, work as temperature
Variation causes thermistor RXOutput voltage U when variation0With variation.E is fixed value voltage,
The temperature characterisitic of thermistor is：In formula, A is constant related with material properties and resistor geometry, B
For constant related with material semiconductor property, T is absolute temperature, due to U0With RXBetween there are certain functional relations, it is known that
U0Situation of change it is known that RXSituation of change, and then be known that temperature situation of change.Measurement temperature it
Before, first to obtain the temperature characterisitic of thermistor.To obtain accurate resistivity measurements, can be measured not with wheatstone bridge
Thermosensitive resistance under synthermal.In a certain range, the relationship for measuring output voltage and temperature, using least square fitting
U0- t relationship.
The working principle of the invention is：Rogowski coil module is for acquiring current signal, and temperature-measuring module is for measuring
The temperature of Rogowski coil, data processing module are fitted for handling the data of coil module and temperature-measuring module
Functional relation between Rogowski coil conducting wire and Rogowski coil temperature, and a resistance value is obtained, pass through monolithic further according to the resistance value
Machine, which controls controllable resistor module and adjusts the resistance value of adjustable resistance, carries out temperature-compensating, and display module shows coil temperature, non-equilibrium
The waveform etc. that the output voltage of electric bridge, the resistance value of adjustable resistance and acquired data are drawn, naturally it is also possible to expand other letters
Breath, communication module are made of the transmission for final data ethernet module and USB module.
The foregoing is merely the preferable embodiments of the present invention, are not intended to limit the present invention in any form, all
Simple modification, same variation are made to the above case study on implementation according to the technical essence of the invention, each fall within protection scope of the present invention
Within.
Claims (5)
1. a kind of current measuring device that high-precision is easy to install, it is characterised in that：Mould is measured including Rogowski coil module, temperature
Block, data processing module, display module, communication module, controllable resistor module, communication module, display module, controllable resistor mould
Block, Rogowski coil module and temperature-measuring module are connected with data processing module, and Rogowski coil module includes Rogowski coil
And integrating circuit, temperature-measuring module are used to measure the temperature of Rogowski coil, controllable resistor module includes adjustable resistance and definite value
Resistance, fixed value resistance one end are connect with Rogowski coil, the connection of one end of the other end and adjustable resistance, the other end of adjustable resistance with
Integrating circuit connection, temperature-measuring module use nonequilibrium bridge structure bridge circuit, communication module and peripheral device communication.
2. a kind of high-precision according to claim 1 current measuring device easy to install, it is characterised in that：The temperature
The bridge circuit of measurement module includes fixed value resistance R1、R2、R3With thermistor RX, fixed value resistance R1、R2A termination power it is negative
Pole, fixed value resistance R1Another termination fixed value resistance R3One end, fixed value resistance R2Another termination thermistor RXOne end,
Fixed value resistance R3The other end, thermistor RXAnother termination positive pole, thermistor RXIt is embedded in Rogowski coil, definite value
Resistance R1、R3Connection midpoint and fixed value resistance R2With thermistor RXConnection midpoint between voltage be U0。
3. a kind of high-precision according to claim 1 or 2 current measuring device easy to install, it is characterised in that：Described
Rogowski coil is open architecture, including coil body 1, non-magnetic material skeleton 2, shaft 3, insulating layer 4, lock 5, non magnetic material
Material skeleton 2 is two semicircular rings, and coil body 1 wraps up insulation uniformly around on non-magnetic material skeleton 2 outside coil body 1
Layer 4, by 5 connection of lock, the other end is rotatablely connected by shaft 3, is latched for 2 one end of non-magnetic material skeleton of two semicircular rings
5 are fixed on insulating layer 4.
4. a kind of high-precision according to claim 1 or 2 current measuring device easy to install, it is characterised in that：Described
Display module is for the temperature data of displays temperature measurement module acquisition, the resistance value of adjustable resistance.
5. a kind of high-precision according to claim 1 or 2 current measuring device easy to install, it is characterised in that：Described
Data processing module includes single-chip microcontroller, fpga chip, SRAM, EPCS, and SRAM uses CY7C006A, and fpga chip uses
Spartan-6FPGA device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810780809.9A CN108918939A (en) | 2018-07-17 | 2018-07-17 | A kind of current measuring device that high-precision is easy to install |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810780809.9A CN108918939A (en) | 2018-07-17 | 2018-07-17 | A kind of current measuring device that high-precision is easy to install |
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| CN108918939A true CN108918939A (en) | 2018-11-30 |
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| CN201810780809.9A Pending CN108918939A (en) | 2018-07-17 | 2018-07-17 | A kind of current measuring device that high-precision is easy to install |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109738684A (en) * | 2019-02-14 | 2019-05-10 | 浙江中控太阳能技术有限公司 | The current detection module and electric current detecting method of tower-type solar thermal power generating system |
| CN113568335A (en) * | 2021-06-28 | 2021-10-29 | 国网天津市电力公司电力科学研究院 | Analog integration and self-calibration system and method for Rogowski coil current transformer |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101625377A (en) * | 2009-08-14 | 2010-01-13 | 河南电力试验研究院 | High-accuracy open type Rogowski coil |
| US20110103112A1 (en) * | 2009-10-30 | 2011-05-05 | Delta Electronics, Inc. | Current sensing signal comparing device, and current sensing signal comparing method |
| CN102759647A (en) * | 2011-04-28 | 2012-10-31 | 三菱电机株式会社 | Converter for meters |
| CN203037265U (en) * | 2013-01-18 | 2013-07-03 | 廊坊市北斗神舟测控仪器有限公司 | Temperature compensating circuit |
| CN104094125A (en) * | 2012-02-03 | 2014-10-08 | 电力电子测量有限公司 | Temperature compensated current measurement |
| CN104377011A (en) * | 2014-11-20 | 2015-02-25 | 国家电网公司 | Half-open type electronic current transformer |
| CN205176106U (en) * | 2015-11-24 | 2016-04-20 | 深圳市创银科技股份有限公司 | Rotatory open -close type current sensor |
| CN106644151A (en) * | 2016-12-23 | 2017-05-10 | 哈尔滨恒誉名翔科技有限公司 | Compass temperature measuring circuit based on MSP430 single chip microcomputer |
| CN206378539U (en) * | 2016-11-09 | 2017-08-04 | 国网浙江省电力公司舟山供电公司 | A kind of high-tension cable monitoring sensor |
| CN208537609U (en) * | 2018-07-17 | 2019-02-22 | 昆明理工大学 | A kind of current measuring device that high-precision is easy to install |
-
2018
- 2018-07-17 CN CN201810780809.9A patent/CN108918939A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101625377A (en) * | 2009-08-14 | 2010-01-13 | 河南电力试验研究院 | High-accuracy open type Rogowski coil |
| US20110103112A1 (en) * | 2009-10-30 | 2011-05-05 | Delta Electronics, Inc. | Current sensing signal comparing device, and current sensing signal comparing method |
| CN102759647A (en) * | 2011-04-28 | 2012-10-31 | 三菱电机株式会社 | Converter for meters |
| CN104094125A (en) * | 2012-02-03 | 2014-10-08 | 电力电子测量有限公司 | Temperature compensated current measurement |
| CN203037265U (en) * | 2013-01-18 | 2013-07-03 | 廊坊市北斗神舟测控仪器有限公司 | Temperature compensating circuit |
| CN104377011A (en) * | 2014-11-20 | 2015-02-25 | 国家电网公司 | Half-open type electronic current transformer |
| CN205176106U (en) * | 2015-11-24 | 2016-04-20 | 深圳市创银科技股份有限公司 | Rotatory open -close type current sensor |
| CN206378539U (en) * | 2016-11-09 | 2017-08-04 | 国网浙江省电力公司舟山供电公司 | A kind of high-tension cable monitoring sensor |
| CN106644151A (en) * | 2016-12-23 | 2017-05-10 | 哈尔滨恒誉名翔科技有限公司 | Compass temperature measuring circuit based on MSP430 single chip microcomputer |
| CN208537609U (en) * | 2018-07-17 | 2019-02-22 | 昆明理工大学 | A kind of current measuring device that high-precision is easy to install |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109738684A (en) * | 2019-02-14 | 2019-05-10 | 浙江中控太阳能技术有限公司 | The current detection module and electric current detecting method of tower-type solar thermal power generating system |
| CN113568335A (en) * | 2021-06-28 | 2021-10-29 | 国网天津市电力公司电力科学研究院 | Analog integration and self-calibration system and method for Rogowski coil current transformer |
| CN113568335B (en) * | 2021-06-28 | 2024-01-30 | 国网天津市电力公司电力科学研究院 | Analog integration and self-calibration system and method for rogowski coil current transformer |
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