CN201117424Y - Electronic type current mutual inductor - Google Patents
Electronic type current mutual inductor Download PDFInfo
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- CN201117424Y CN201117424Y CNU2007201900578U CN200720190057U CN201117424Y CN 201117424 Y CN201117424 Y CN 201117424Y CN U2007201900578 U CNU2007201900578 U CN U2007201900578U CN 200720190057 U CN200720190057 U CN 200720190057U CN 201117424 Y CN201117424 Y CN 201117424Y
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Abstract
The utility model relates to an electronic current transformer which includes a high voltage side and a low voltage side; the high voltage side is provided with a signal measuring unit used for measuring the current of the bus of the high voltage side, a high voltage side processing unit and an electro-optic isolating unit belonging to either the high voltage side and the low voltage side; the low voltage side is provided with a processing unit, wherein, the high voltage side is provided with a first channel high voltage side processing unit and a second channel high voltage side processing unit, a first multi-channel switching unit and a second multi-channel switching unit; the low voltage side processing unit includes a base frequency acquiring unit and a harmonic analyzing unit. The electronic current transformer of the utility model can acquire the harmonic component of the bus current, and realize convenient and fast calibration.
Description
Technical field
The utility model relates to current transformer, particularly relates to a kind of electronic current mutual inductor.
Background technology
Current transformer is one of electric component important in the electric power system, and accurate measurement, electric energy metrical, relaying protection, system monitoring and the network analysis of electric current in the electric power system all had important effect.Be extensive use of electromagnetic current transducer in the electric power system at present, the electromagnetic current transducer operation principle is similar with transformer, have high-pressure side and low-pressure side equally, the high-pressure side is connected in the bus, the few electric current of the number of turn is big, low-pressure side number of turn multiple current is little, so current transformer can be measured very big bus current.Continuous development along with electric power system, improving constantly of line voltage grade, electromagnetic current transducer is faced with increasing problem, and for example Insulation Problems, magnetic saturation problem, dynamic range are little etc., and electronic current mutual inductor is owing to not existing the problems referred to above to obtain fast development.
Utilize the optical fiber technology transmitting optical signal between the electronic current mutual inductor high and low pressure side, therefore can realize good insulation reliably, adapt to the modern power systems automation thus, digitized developing direction, as shown in Figure 1, the signal measurement unit of electronic current mutual inductor is for measuring the transducer of bus current, after the analog-to-digital conversion operation of its output signal through the high-pressure side processing unit, through transferring to the low-pressure side processing unit behind the electric light isolated location that adheres to high-pressure side and low-pressure side separately, wherein, described electric light isolated location comprises the photoelectric conversion unit of on high-tension side electrooptic switching element and low-pressure side.
In the data that the high-pressure side transmission that low-pressure side gets access to comes, owing to power quality problem includes the high order harmonic component composition, and Harmonic Parameters is to weigh the important technology index of the quality of power supply, in the prior art, the measuring unit of low-pressure side or processing unit can't obtain harmonic component from the data that the high-pressure side transmission comes, this situation is to be difficult to competent for the application that the high quality of power supply requires.
In addition, the verification work of electronic current mutual inductor adopts the instrumentation unification to carry out in national metrological service at present, and check-verifying period is long, expense is high, is difficult to satisfy practical application request; On the other hand, electromagnetic current transducer is technology maturation, stable for electronic current mutual inductor, can be used to provide verifying function to electronic current mutual inductor, but electronic current mutual inductor in the prior art can't utilize electromagnetic current transducer that it is carried out verification owing to lack the corresponding interface, has caused the difficulty of electronic current mutual inductor verification work.
In addition, the high-pressure side long-term work of electronic current mutual inductor is under abominable electromagnetic interference environment, to cause whole electronic current mutual inductor to work in case break down, therefore on high-tension side redundancy backup design is necessary very much, described on high-tension side redundancy backup design is meant that the high-pressure side possesses two-way high-pressure side processing unit simultaneously, one the road when breaking down, and devotes oneself to work after can being activated in another road.On high-tension side redundancy backup design must rely on the cooperation of lower-voltage circuit to realize, lack low-pressure side in the prior art on high-tension side relevant control circuit, if break down in the high-pressure side, can't also just be difficult to realize on high-tension side redundancy backup design by low-pressure side on high-tension side relevant control circuit is got rid of it.
Summary of the invention
In view of this, main purpose of the present utility model is to provide a kind of electronic current mutual inductor, can obtain the harmonic component of bus current, can also realize the verification to this electronic current mutual inductor, also can be transmitted control signal to the high-pressure side by low-pressure side.
For achieving the above object, the technical solution of the utility model is achieved in that
A kind of electronic current mutual inductor, comprise high-pressure side and low-pressure side, the high-pressure side has the signal measurement unit of measuring current value on the high-voltage side bus, the high-pressure side processing unit, adhere to the electric light isolated location of high-pressure side and low-pressure side separately, after isolating, the electric light that is used to realize two-way high-pressure side processing unit dateout is transferred to the low-pressure side processing unit, low-pressure side has processing unit, the high-pressure side has the two-way measured value signal analog-to-digital first via high-pressure side processing unit of realization and the second tunnel high-pressure side processing unit, with the first multi channel selecting unit of realizing that two-way high-pressure side processing unit input signal multichannel is switched, with the second multi channel selecting unit of realizing that two-way high-pressure side processing unit dateout multichannel is switched, the low-pressure side processing unit comprises the fundamental frequency acquiring unit that is used for from the extracting data bus current fundamental frequency of the first via or the second tunnel high-pressure side processing unit transmission, with the harmonic component harmonic analysis unit that from the data of the first via or the second tunnel high-pressure side processing unit transmission, obtains bus current in conjunction with described fundamental frequency, wherein, described measured value signal is transferred to two-way high-pressure side processing unit through the first multi channel selecting unit, and the second multi channel selecting unit connection first via high-pressure side processing unit and the second tunnel high-pressure side processing unit are to the electric light isolated location.
Wherein, described high-pressure side also has the signal condition unit of level conversion between the output signal that realizes signal measurement unit and the high-pressure side processing unit input signal, the described signal condition unit connection signal measurement unit and the first multi channel selecting unit.
Wherein, described fundamental frequency acquiring unit comprises that the filtering first via or the second tunnel high-pressure side processing unit transmit the filter unit of higher harmonic components in the data of coming and try to achieve the fundamental frequency extraction unit of bus current fundamental frequency according to trigonometric function with difference eliminate indigestion and least square relation.
Wherein, described harmonic analysis unit is a discrete Fourier transform unit, is used for according to described fundamental frequency the first via or the second tunnel high-pressure side next data of processing unit transmission being carried out discrete Fourier transform (DFT), obtains the harmonic component of bus current.
Described high-pressure side also has reference voltage source, and described reference voltage source is connected to the first multi channel selecting unit, provides the canonical reference voltage signal by the first multi channel selecting unit for two-way high-pressure side processing unit.
Described low-pressure side also has the electromagnetic current transducer interface, and described electromagnetic current transducer interface connects external electromagnetic current transducer and low-pressure side processing unit, and the output signal of external electromagnetic current transducer is transferred to the low-pressure side processing unit.
Wherein, also have outer signal conditioning unit between described electromagnetic current transducer interface and the low-pressure side processing unit, realize the level conversion between the input signal of the output signal of external electromagnetic current transducer and low-pressure side processing unit.
Described low-pressure side also has signal output unit, signal output unit connects the low-pressure side processing unit, described signal output unit comprises D/A conversion unit and the analog output signal interface of realizing the output of low-pressure side processing unit analog signal, and described signal output unit also comprises the Ethernet card and the digital output signal interface of the digital signal output that realizes the low-pressure side processing unit.
Described low-pressure side also has the display unit of realizing that low-pressure side processing unit output signal shows, and described display unit connects the low-pressure side processing unit.
Described low-pressure side also has the input unit that receives user input instruction, and described input unit is connected to the low-pressure side processing unit, and correspondingly, low-pressure side also has according to user input instruction to high-pressure side processing unit transmission of control signals control unit, high-pressure side.
Wherein, the described electric light isolated location that adheres to high-pressure side and low-pressure side separately comprises realizes the high-pressure side toward the on high-tension side electrooptic switching element of low-pressure side data signals transmitted photoelectricity isolation and the photoelectric conversion unit of low-pressure side, and photoelectric conversion unit and the on high-tension side electrooptic switching element of realizing the low-pressure side that the past high-pressure side of low-pressure side control signals transmitted photoelectricity is isolated.
Electronic current mutual inductor of the present utility model has the following advantages:
1) obtains the fundamental frequency of bus current by filter unit and fundamental frequency extraction unit, and the bus current signal is carried out discrete Fourier transform (DFT), can obtain the harmonic component of bus current thus, have the engineering practical value for weighing the quality of power supply according to described fundamental frequency.
2) be provided with the interface of electromagnetic current transducer in low-pressure side, can realize on-the-spotly, therefore can improve the flexibility of checking electronic type transformers work on the spot by the verification of electromagnetic current transducer for electronic current mutual inductor.
3) low-pressure side is provided with on high-tension side relevant control circuit, therefore can be transmitted control signal to the high-pressure side by low-pressure side, assists to realize on high-tension side redundancy backup design.
Description of drawings
Fig. 1 is the structure chart of electronic current mutual inductor in the prior art;
Fig. 2 is the structure chart of the utility model electronic current mutual inductor.
Embodiment
Below in conjunction with drawings and the specific embodiments the utility model is further described in more detail.
As shown in Figure 2, electronic current mutual inductor of the present utility model comprises high-pressure side and low-pressure side, the high-pressure side has signal measurement unit, the signal condition unit, two-way high-pressure side processing unit, be respectively the high-pressure side processing unit of the first via shown in the figure and the second tunnel high-pressure side processing unit, and the two-way MCPU multiple call processing unit, be respectively the first multi channel selecting unit shown in the figure and the second multi channel selecting unit; Adhere to the electric light isolated location of high-pressure side and low-pressure side separately, low-pressure side has processing unit, the low-pressure side processing unit comprises fundamental frequency acquiring unit and harmonic analysis unit, the electric light isolated location comprises on high-tension side electrooptic switching element and photoelectric conversion unit, and the photoelectric conversion unit of low-pressure side and electrooptic switching element, wherein
Signal measurement unit is used to measure the current value on the high-voltage side bus, sends to the first via high-pressure side processing unit and the second tunnel high-pressure side processing unit behind the measuring-signal process signal condition unit of output and the first multi channel selecting unit;
The signal condition unit, the multi channel selecting unit of the connection signal measurement unit and the first multichannel handoff functionality is used to realize the output signal of signal measurement unit and the level conversion between the processing unit input signal of high-pressure side;
The first multi channel selecting unit is used for the bus current signal after the signal condition unit level conversion is divided into two-way according to time slot, delivers to the first via high-pressure side processing unit and the second tunnel high-pressure side processing unit respectively;
The first via high-pressure side processing unit and the second tunnel high-pressure side processing unit, be used to realize the analog-to-digital conversion of bus current signal, the output digital signal, the high-pressure side processing unit can use embedded chips such as single-chip microcomputer, digital signal processing chip or ARM to realize, described two-way high-pressure side processing unit is used for the redundancy backup design of electronic current mutual inductor, promptly one the road when breaking down, and another road can be activated and come into operation;
The second multi channel selecting unit is used for by time slot the digital data transmission of first via high-pressure side processing unit and the output of the second tunnel high-pressure side processing unit on high-tension side electrooptic switching element;
On high-tension side electrooptic switching element is used for the electric light conversion of the digital signal exported the second multi channel selecting unit, to the photoelectric conversion unit transmitting optical signal of low-pressure side;
The photoelectric conversion unit of low-pressure side is used for the light signal that on high-tension side electrooptic switching element transmission comes is converted to the signal of telecommunication, and with this signal of telecommunication, also is that the data that high-pressure side processing unit transmission comes send to the low-pressure side processing unit;
The fundamental frequency acquiring unit comprises filter unit and fundamental frequency extraction unit, wherein, filter unit be used for the filtering first via or the second tunnel high-pressure side processing unit through the electric light isolated location after the higher harmonic components of the data transmitted of institute, stay fundametal compoment, the fundamental frequency extraction unit is used for difference eliminate indigestion and least square relation described fundametal component being obtained the bus current fundamental frequency according to trigonometric function;
The harmonic analysis unit is a discrete Fourier transform unit, be used for according to described fundamental frequency to the first via or the second tunnel high-pressure side processing unit through the electric light isolated location after the transmission data of coming carry out discrete Fourier transform (DFT), obtain the harmonic component of bus current, described harmonic analysis unit further is other digital signal processing units, as long as can realize harmonic analysis according to fundamental frequency.
Through above-mentioned signal measurement unit-multi channel selecting unit, the signal condition unit-first-photoelectric conversion unit-fundamental frequency acquiring unit of processing unit-second multi channel selecting unit, two-way high-pressure side-on high-tension side electrooptic switching element-low-pressure side and signals collecting, conversion and the analysis path of harmonic analysis unit, the bus current signal of signal measurement unit output can be divided into two-way, one the tunnel is used to obtain the fundamental frequency of bus current, and one the tunnel is used for obtaining according to obtaining fundamental frequency the harmonic component of bus current.
The first multi channel selecting unit and the second road gating unit are except according to time slot and the first via high-pressure side processing unit and the second tunnel high-pressure side processing unit transmission signals, can also receive first via high-pressure side processing unit and the second tunnel high-pressure side processing unit control signal according to actual conditions to it, the first multi channel selecting unit shown in the figure to the solid arrow of the first via high-pressure side processing unit and the second tunnel high-pressure side processing unit represents that the signal after the first multi channel selecting unit is with signal condition unit level conversion is divided into two-way according to time slot, delivers to the first via high-pressure side processing unit and the second tunnel high-pressure side processing unit respectively; The dotted arrow of first via high-pressure side processing unit and processing unit to the first multi channel selecting unit, the second tunnel high-pressure side represents that the first via high-pressure side processing unit and the second tunnel high-pressure side processing unit are to the first multi channel selecting unit sending controling instruction; Similarly, the solid line between the second multi channel selecting unit and first via high-pressure side processing unit and the second tunnel high-pressure side processing unit, dotted arrow are also represented transmission data and control command respectively.
In addition, the high-pressure side also has reference voltage source, and described reference voltage source is connected to the first multi channel selecting unit, and being used for provides the canonical reference voltage signal by the first multi channel selecting unit for first via high-pressure side processing unit and the second tunnel high-pressure side processing unit.
In order to realize utilizing the verification of electromagnetic current transducer to electronic current mutual inductor described in the utility model, low-pressure side at electronic current mutual inductor described in the utility model also has the electromagnetic current transducer interface, described electromagnetic current transducer interface connects external electromagnetic current transducer and low-pressure side processing unit, be used for the output signal of external electromagnetic current transducer is transferred to the low-pressure side processing unit, in order to match with described electromagnetic current transducer interface, can also have outer signal conditioning unit between described electromagnetic current transducer interface and the low-pressure side processing unit, described outer signal conditioning unit is used to realize the level conversion between the input signal of the output signal of external electromagnetic current transducer and low-pressure side processing unit.
In addition, described low-pressure side also has signal output unit, signal output unit connects the low-pressure side processing unit, described signal output unit comprises D/A conversion unit and analog output signal interface, be used to realize the analog signal output of low-pressure side processing unit, described signal output unit also comprises Ethernet card and digital output signal interface, is used to realize the digital signal output of low-pressure side processing unit.Signal output unit can also comprise the signal output unit of other types, for example serial data communication interface etc.
In addition, described low-pressure side also has display unit, and described display unit connects the low-pressure side processing unit, is used to realize the demonstration of low-pressure side processing unit output signal, and described display unit can be liquid crystal display screen or multistage LED charactron etc.
In order to realize that low-pressure side of the present utility model is on high-tension side relevant control circuit, described low-pressure side also has input unit, described input unit can be external connection keyboard or touch-screen etc., be connected to the low-pressure side processing unit, be used to receive user's input on high-tension side control command, correspondingly, described low-pressure side processing unit also comprises control unit, high-pressure side, be used for according to user input on high-tension side control command to high-pressure side processing unit transmission of control signals.Described for behind on high-tension side control command the process electrooptic switching element and on high-tension side photoelectric conversion unit of low-pressure side, transfer to the on high-tension side first high-pressure side processing unit and the second high-pressure side processing unit, realize low-pressure side on high-tension side control with this, assist to realize on high-tension side redundancy backup design.
The above is preferred embodiment of the present utility model only, is not to be used for limiting protection range of the present utility model.Those skilled in that art should be able to associate; high-pressure side and low-pressure side have other miscellaneous function unit; utilize other unit to realize that fundamental frequency obtains and harmonic analysis; the signal output unit of low-pressure side and input unit realize by other functional units, and utilize the distortion of the facies type that structure of the present utility model done all should belong to protection range of the present utility model.
Claims (11)
1, a kind of electronic current mutual inductor, comprise high-pressure side and low-pressure side, the high-pressure side has the signal measurement unit of measuring current value on the high-voltage side bus, the high-pressure side processing unit, adhere to the electric light isolated location of high-pressure side and low-pressure side separately, after isolating, the electric light that is used to realize two-way high-pressure side processing unit dateout is transferred to the low-pressure side processing unit, low-pressure side has processing unit, it is characterized in that, the high-pressure side has the two-way measured value signal analog-to-digital first via high-pressure side processing unit of realization and the second tunnel high-pressure side processing unit, with the first multi channel selecting unit of realizing that two-way high-pressure side processing unit input signal multichannel is switched, with the second multi channel selecting unit of realizing that two-way high-pressure side processing unit dateout multichannel is switched, the low-pressure side processing unit comprises the fundamental frequency acquiring unit that is used for from the extracting data bus current fundamental frequency of the first via or the second tunnel high-pressure side processing unit transmission, with the harmonic component harmonic analysis unit that from the data of the first via or the second tunnel high-pressure side processing unit transmission, obtains bus current in conjunction with described fundamental frequency, wherein, described measured value signal is transferred to two-way high-pressure side processing unit through the first multi channel selecting unit, and the second multi channel selecting unit connection first via high-pressure side processing unit and the second tunnel high-pressure side processing unit are to the electric light isolated location.
2, electronic current mutual inductor according to claim 1, it is characterized in that, described high-pressure side also has the signal condition unit of level conversion between the output signal that realizes signal measurement unit and the high-pressure side processing unit input signal, the described signal condition unit connection signal measurement unit and the first multi channel selecting unit.
3, electronic current mutual inductor according to claim 1, it is characterized in that, described fundamental frequency acquiring unit comprises that the filtering first via or the second tunnel high-pressure side processing unit transmit the filter unit of higher harmonic components in the data of coming and try to achieve the fundamental frequency extraction unit of bus current fundamental frequency according to trigonometric function with difference eliminate indigestion and least square relation.
4, electronic current mutual inductor according to claim 1, it is characterized in that, described harmonic analysis unit is a discrete Fourier transform unit, be used for the first via or the second tunnel high-pressure side next data of processing unit transmission being carried out discrete Fourier transform (DFT), obtain the harmonic component of bus current according to described fundamental frequency.
5, electronic current mutual inductor according to claim 1, it is characterized in that, described high-pressure side also has reference voltage source, and described reference voltage source is connected to the first multi channel selecting unit, provides the canonical reference voltage signal by the first multi channel selecting unit for two-way high-pressure side processing unit.
6, electronic current mutual inductor according to claim 1, it is characterized in that, described low-pressure side also has the electromagnetic current transducer interface, described electromagnetic current transducer interface connects external electromagnetic current transducer and low-pressure side processing unit, and the output signal of external electromagnetic current transducer is transferred to the low-pressure side processing unit.
7, electronic current mutual inductor according to claim 6, it is characterized in that, also have outer signal conditioning unit between described electromagnetic current transducer interface and the low-pressure side processing unit, realize the level conversion between the input signal of the output signal of external electromagnetic current transducer and low-pressure side processing unit.
8, electronic current mutual inductor according to claim 1, it is characterized in that, described low-pressure side also has signal output unit, signal output unit connects the low-pressure side processing unit, described signal output unit comprises D/A conversion unit and the analog output signal interface of realizing the output of low-pressure side processing unit analog signal, and described signal output unit also comprises the Ethernet card and the digital output signal interface of the digital signal output that realizes the low-pressure side processing unit.
9, electronic current mutual inductor according to claim 1 is characterized in that, described low-pressure side also has the display unit of realizing that low-pressure side processing unit output signal shows, and described display unit connects the low-pressure side processing unit.
10, electronic current mutual inductor according to claim 1, it is characterized in that, described low-pressure side also has the input unit that receives user input instruction, described input unit is connected to the low-pressure side processing unit, correspondingly, low-pressure side also has according to user input instruction to high-pressure side processing unit transmission of control signals control unit, high-pressure side.
11, electronic current mutual inductor according to claim 10, it is characterized in that, the described electric light isolated location that adheres to high-pressure side and low-pressure side separately comprises realizes the high-pressure side toward the on high-tension side electrooptic switching element of low-pressure side data signals transmitted photoelectricity isolation and the photoelectric conversion unit of low-pressure side, and photoelectric conversion unit and the on high-tension side electrooptic switching element of realizing the low-pressure side that the past high-pressure side of low-pressure side control signals transmitted photoelectricity is isolated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201900578U CN201117424Y (en) | 2007-11-07 | 2007-11-07 | Electronic type current mutual inductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201900578U CN201117424Y (en) | 2007-11-07 | 2007-11-07 | Electronic type current mutual inductor |
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| CN201117424Y true CN201117424Y (en) | 2008-09-17 |
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| CNU2007201900578U Expired - Fee Related CN201117424Y (en) | 2007-11-07 | 2007-11-07 | Electronic type current mutual inductor |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101907649A (en) * | 2010-07-07 | 2010-12-08 | 中国电力科学研究院 | FPGA-based sample data interface circuit for electronic mutual inductor |
| CN101916647A (en) * | 2010-08-23 | 2010-12-15 | 山东电力研究院 | Multiband measurement digital linear alternating current transformer and measuring method thereof |
| CN106154130A (en) * | 2016-08-17 | 2016-11-23 | 山东理工大学 | A kind of photo-electric surge voltage test device and method |
| CN108614142A (en) * | 2018-04-28 | 2018-10-02 | 宁波三星医疗电气股份有限公司 | A kind of improved electric power terminal |
| CN112986889A (en) * | 2020-12-08 | 2021-06-18 | 浙江武义电气安装工程有限公司 | System and method for checking current transformer for distribution network |
-
2007
- 2007-11-07 CN CNU2007201900578U patent/CN201117424Y/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101907649A (en) * | 2010-07-07 | 2010-12-08 | 中国电力科学研究院 | FPGA-based sample data interface circuit for electronic mutual inductor |
| CN101916647A (en) * | 2010-08-23 | 2010-12-15 | 山东电力研究院 | Multiband measurement digital linear alternating current transformer and measuring method thereof |
| CN106154130A (en) * | 2016-08-17 | 2016-11-23 | 山东理工大学 | A kind of photo-electric surge voltage test device and method |
| CN106154130B (en) * | 2016-08-17 | 2018-11-13 | 山东理工大学 | A kind of photo-electric surge voltage test device and method |
| CN108614142A (en) * | 2018-04-28 | 2018-10-02 | 宁波三星医疗电气股份有限公司 | A kind of improved electric power terminal |
| CN112986889A (en) * | 2020-12-08 | 2021-06-18 | 浙江武义电气安装工程有限公司 | System and method for checking current transformer for distribution network |
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Granted publication date: 20080917 Termination date: 20121107 |