CN203949993U - A kind of device based on voltage difference and electric current difference measuring transformer efficiency - Google Patents
A kind of device based on voltage difference and electric current difference measuring transformer efficiency Download PDFInfo
- Publication number
- CN203949993U CN203949993U CN201420387040.1U CN201420387040U CN203949993U CN 203949993 U CN203949993 U CN 203949993U CN 201420387040 U CN201420387040 U CN 201420387040U CN 203949993 U CN203949993 U CN 203949993U
- Authority
- CN
- China
- Prior art keywords
- transformer
- voltage
- power
- difference
- efficiency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
Abstract
The utility model proposes a kind of device based on voltage difference and electric current difference measuring transformer efficiency.It relates to power measurement and efficiency metering field, and it is the precision of measuring in order to improve efficiency.This method is used voltage, electric current to get the magnitude difference of difference measured to reduce (power), by suitable circuit, converts, and the difference by the loss power of measured transformer from power input and output power, becomes two smaller power sums and measured.This measuring method can be converted into the difference measurement of two larger electrical quantities the summation of two small electric amounts, thereby improves measuring accuracy.This method can be carried out efficiency measurement under running status, both can be used for transformer efficiency off-line measurement, can, for the efficiency metering under any duty, have more and have wide practical use again.The tested transformer that the utility model relates to can be single transformer, can be also three-phase transformer.
Description
Technical field
The utility model belongs to electricity field, especially relates to a kind of device based on voltage difference and electric current difference measuring transformer efficiency.
Background technology
Transformer is one of major equipment in electric system.The height of transformer energy transfer efficiency is the important component part of whole electric system energy efficiency.Energy loss on transformer has caused electric company, electricity consumption user's economic loss.The efficiency that improves transformer is the direction of International Power domain expert long-term endeavour.And to the accurate detection of transformer efficiency, be the basis of monitoring transformer efficiency.Transformer from plant produced out after, the calibrating of need to dispatching from the factory; After putting into operation, also need at set intervals to carry out routine inspection.Transformer efficiency is one of main Index for examination.
Under current national standard, the detection of transformer efficiency has been used to the method for measuring open circuit loss and short circuit loss, the another kind of method extensively adopting is the method that power input and output power are subtracted each other.The approximate hypothesis that method unloaded and short circuit loss can separately be measured based on loss power, has certain approximation.Although the method that power input and output power are subtracted each other does not contain as above approximate hypothesis, but because transformer efficiency is conventionally higher (conventionally more than 80%-90%, what have even surpasses 99%), so power input and output power are numerically more approaching, and much larger than loss power.Therefore the resulting loss power degree of accuracy of the method is lower, and then has affected the degree of accuracy of efficiency metering.The new method that this patent proposes, than above two kinds of methods, has obvious advantage.First, the rational circuit conversion of this method utilization, can be by measuring two smaller powers and being added the numerical value that obtains loss power.This method make the actual measurement gear range ability of surveying instrument used and the size of loss power more approaching, thereby obtain higher power measurement accuracy.Secondly, this method needn't can only off-line measurement as measured in open circuit loss and short circuit loss.This method is due to the not restriction of load connecting being carried in power supply on transformer, transformer, so can realize on-line measurement.
Utility model content
The utility model is mainly to solve the existing technical matters of prior art; A kind of experimental flexibility that increases the metering of transformer efficiency is provided, has improved the accuracy of metering transformer efficiency, and can be for a kind of device based on voltage difference and electric current difference measuring transformer efficiency of transformer efficiency on-line measurement.
It is to solve the existing technical matters of prior art that the utility model also has an object; Provide a kind of and accurate to be measuredly by voltage, electric current, done the mathematical operations such as poor or summation, multiplication and division by be difficult for surveying, be converted into and be easy to measure and/or be easy to survey other accurate electrical quantities, in the situation that final measuring object is consistent, change actual object of measurement, reduced a kind of device based on voltage difference and electric current difference measuring transformer efficiency of experiment difficulty.
Above-mentioned technical matters of the present utility model is mainly solved by following technical proposals:
A device based on voltage difference and electric current difference measuring transformer efficiency, is characterized in that,
First at first voltage transformer (VT) of two terminations of transformer primary side or power end, and on earth return circuit, be connected in series first current transformer or have the first hook type current transformer of identical no-load voltage ratio with the first current transformer;
Then at second voltage mutual inductor of two terminations of Circuit Fault on Secondary Transformer or load end, and on earth return circuit, be connected in series second current transformer or have the second hook type current transformer of identical no-load voltage ratio with the second current transformer;
Finally, the Secondary Winding at the first voltage transformer (VT) connects the 3rd power meter voltage port; The secondary windings in series of the Secondary Winding of the first voltage transformer (VT) and second voltage mutual inductor, and the voltage difference of the Secondary Winding of the Secondary Winding of the first voltage transformer (VT) and second voltage mutual inductor terminates at the voltage port of the first power meter; Secondary Winding forward serial connection the 3rd power meter the forward of the first current transformer are connected in series the second power meter electric current port; The Secondary Winding forward of the second current transformer is connected in series the first power meter electric current port and is oppositely connected in series the second power meter electric current port.
The creationary feature of electrical measurement and the appropriate mathematical skill of combining of the utility model, the circuit transform method being derived not only can be used for the metering of transformer efficiency, and the improvement of other measurement of correlation tests is provided and inspired and use for reference.The method of sort circuit conversion accurate is to be measuredly done the mathematical operations such as poor or summation, multiplication and division by voltage, electric current by being difficult for surveying, be converted into and be easy to measure and/or be easy to survey other accurate electrical quantities, in the situation that final measuring object is consistent, changed actual object of measurement, reduce experiment difficulty, improved the degree of accuracy of measuring.
A kind of device based on voltage difference and electric current difference measuring transformer efficiency above-mentioned, is characterized in that, if on-line measurement replaces in current transformer place in circuit with hook type current transformer.
Therefore, the utlity model has following advantage: 1. increase the experimental flexibility of transformer efficiency metering, improved the accuracy of metering transformer efficiency, and can be for the on-line measurement of transformer efficiency; 2. by be difficult for surveying, accurate to be measuredly by voltage, electric current, do the mathematical operations such as poor or summation, multiplication and division, be converted into and be easy to measure and/or be easy to survey other accurate electrical quantities, in the situation that final measuring object is consistent, change actual object of measurement, reduced experiment difficulty.
Accompanying drawing explanation
Fig. 1 is method flow schematic diagram of the present utility model.
Fig. 2 is basic circuit schematic diagram of the present utility model (single-phase);
Fig. 3 a is basic circuit schematic diagram of the present utility model (three-phase);
Fig. 3 b is the basic circuit schematic diagram (three-phase) of the measurement loss power that relates to of the utility model;
Embodiment
Below by embodiment, and by reference to the accompanying drawings, the technical solution of the utility model is described in further detail.
Embodiment:
The instrument that this method is used comprises: transformer, power supply, load, voltage transformer (VT), current transformer, power meter.First at first voltage transformer (VT) of two terminations of transformer primary side or power end, and on earth return circuit, be connected in series first current transformer or have the first hook type current transformer of identical no-load voltage ratio with the first current transformer;
Then at second voltage mutual inductor of two terminations of Circuit Fault on Secondary Transformer or load end, and on earth return circuit, be connected in series second current transformer or have the second hook type current transformer of identical no-load voltage ratio with the second current transformer;
Finally, the Secondary Winding at the first voltage transformer (VT) connects the 3rd power meter voltage port; The secondary windings in series of the Secondary Winding of the first voltage transformer (VT) and second voltage mutual inductor, and the voltage difference of the Secondary Winding of the first voltage transformer (VT) and second voltage mutual inductor terminates at the voltage port of the first power meter; Secondary Winding forward serial connection the 3rd power meter the forward of the first current transformer are connected in series the second power meter electric current port; The Secondary Winding forward of the second current transformer is connected in series the first power meter electric current port and is oppositely connected in series the second power meter electric current port.
Wherein, metering circuit is built according to measure equation, the primary side voltage of transformer, electric current, and secondary side voltage, electric current are all drawn by mutual inductor, are used to form voltage difference, difference between current or offer power meter to carry out power measurement.
Here measured transformer comprises single transformer and three-phase transformer, and electric pressure is not limit.The connection layout of three-phase transformer be take Dy11 as example (seeing Fig. 3), but is not limited only to Dy11.The wiring that the wiring of three-phase transformer is equivalent to single transformer connects one time on each phase winding, connects altogether three times identical circuit (seeing Fig. 3 (a)).The loss power of three-phase transformer is measured according to the wiring of Fig. 3 (b).Total loss power is that power meter 1 is to the power addition of power meter 6.In a limited number of situations of actual equipment, can grouping mea-sure (but need to keep power supply and loading condition constant).The total power input of three-phase transformer can be used two watts of meter methods to use two power meters to measure, also can use three power meters to measure (for high-tension transformer with the wiring that is similar to single plane method, measure and all by voltage, current transformer, undertaken), no longer accompanying drawing explanation herein.
Mutual inductor, the voltage using, the no-load voltage ratio of current transformer should meet certain relation to meet new efficiency metering formula, also will meet the measurement range of power meter simultaneously.
Power supply, the power supply of transformer can be electric source for test purposes, can be also the input end of the transformer that is in operation;
Load, the load of transformer can be test load, can be also the output terminal of the transformer that is in operation;
Power meter, measures the power meter that power is used, and range should be with measured flux matched.The energy of electromagnetic field that the receiving coil that adds certain iron core to combine transmits for receiving transmitting coil; Receiving coil is substantially similar with the formation of transmitting coil, adjust combination and the layout of iron core or coil, the electric energy that receiving coil can be received reaches maximum or in the situation that can receiving certain electric energy, increases as far as possible the distance between receiving coil and transmitting coil;
During calculating, first, by the first voltage source mutual inductor and the second current transformer, record respectively transformer primary side and secondary side current and will do the difference electric current that obtains after poor as one of input signal of the second power meter;
Then, by the first voltage transformer (VT) and second voltage mutual inductor, record respectively transformer primary side and secondary side voltage and will do the difference voltage that obtains after poor as one of input signal of power meter the first power meter;
Finally, using the voltage of difference electric current and transformer the first voltage transformer secondary side, together as the second power meter input signal, the result recording is power A; Using the electric current that obtains difference voltage and transformer the second Current Transformer Secondary side, together as the first power meter input signal, the result recording is power B; The result that the 3rd power meter records is power C; Counting power A after mutual inductor ratio conversion and the power sum of power B is the transformer loss power recording,
P
loss=U
1(I
1-I
2/k)+I
2(U
1/k-U
2);
In formula, P
lossrepresent transformer loss power, U
1, I
1represent voltage, the electric current of transformer primary side or mains side, U
2, I
2represent voltage, the electric current of Circuit Fault on Secondary Transformer or load-side, k is the constant of a setting; The value of k is: no-load voltage ratio ± 20% of the tested transformer of k=, makes voltage difference (U
1/ k-U
2) and electric current difference (I
1-I
2/ k) size is enough little, is convenient to power meter and measures;
Compare transformer loss power and power input, can access the efficiency of transformer, efficiency computing formula is:
Specific embodiment described herein is only to the explanation for example of the utility model spirit.The utility model person of ordinary skill in the field can make various modifications or supplements or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present utility model or surmount the defined scope of appended claims.
Claims (2)
1. the device based on voltage difference and electric current difference measuring transformer efficiency, is characterized in that,
First at first voltage transformer (VT) of two terminations of transformer primary side or power end, and on earth return circuit, be connected in series first current transformer or have the first hook type current transformer of identical no-load voltage ratio with the first current transformer;
Then at second voltage mutual inductor of two terminations of Circuit Fault on Secondary Transformer or load end, and on earth return circuit, be connected in series second current transformer or have the second hook type current transformer of identical no-load voltage ratio with the second current transformer;
Finally, the Secondary Winding at the first voltage transformer (VT) connects the 3rd power meter voltage port; The secondary windings in series of the Secondary Winding of the first voltage transformer (VT) and second voltage mutual inductor, and the voltage difference of the Secondary Winding of the Secondary Winding of the first voltage transformer (VT) and second voltage mutual inductor terminates at the voltage port of the first power meter; Secondary Winding forward serial connection the 3rd power meter the forward of the first current transformer are connected in series the second power meter electric current port; The Secondary Winding forward of the second current transformer is connected in series the first power meter electric current port and is oppositely connected in series the second power meter electric current port.
2. a kind of device based on voltage difference and electric current difference measuring transformer efficiency according to claim 1, is characterized in that, if on-line measurement replaces in current transformer place in circuit with hook type current transformer.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201420387040.1U CN203949993U (en) | 2014-07-14 | 2014-07-14 | A kind of device based on voltage difference and electric current difference measuring transformer efficiency |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201420387040.1U CN203949993U (en) | 2014-07-14 | 2014-07-14 | A kind of device based on voltage difference and electric current difference measuring transformer efficiency |
Publications (1)
Publication Number | Publication Date |
---|---|
CN203949993U true CN203949993U (en) | 2014-11-19 |
Family
ID=51892021
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201420387040.1U Expired - Fee Related CN203949993U (en) | 2014-07-14 | 2014-07-14 | A kind of device based on voltage difference and electric current difference measuring transformer efficiency |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN203949993U (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104076226A (en) * | 2014-07-14 | 2014-10-01 | 武汉大学 | Device and method for measuring energy efficiency of transformer based on voltage difference value and current difference value |
CN110208603A (en) * | 2019-06-05 | 2019-09-06 | 江南大学 | A kind of transformer voltage phase difference measuring apparatus and measurement method |
-
2014
- 2014-07-14 CN CN201420387040.1U patent/CN203949993U/en not_active Expired - Fee Related
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104076226A (en) * | 2014-07-14 | 2014-10-01 | 武汉大学 | Device and method for measuring energy efficiency of transformer based on voltage difference value and current difference value |
CN104076226B (en) * | 2014-07-14 | 2017-11-10 | 武汉大学 | Device and method based on voltage difference and current differential measuring transformer efficiency |
CN110208603A (en) * | 2019-06-05 | 2019-09-06 | 江南大学 | A kind of transformer voltage phase difference measuring apparatus and measurement method |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN202794334U (en) | Wide-range direct current standard electric energy meter | |
CN103207379B (en) | Method and device for measuring direct current magnetic bias error characteristics of current transformer | |
CN201444193U (en) | Comprehensive error detection device used for digital electric energy measuring device | |
CN204945357U (en) | A kind of electronic mutual inductor steady state error measuring means | |
CN104730485A (en) | GIS type current transformer test method | |
CN202758062U (en) | Overall metering error detection system of digital transformer station electric energy metering device | |
CN103063895B (en) | Pliers-shaped anti-interference current transformer and transformer iron core grounding current testing system | |
CN103543428A (en) | Miniature current transformer ratio error self-calibration system | |
CN103018703A (en) | Current/voltage conversion traceability method for precision alternating current measurement | |
CN103675749A (en) | Performance detector of electric energy meter under direct current and even harmonic conditions | |
CN104076226A (en) | Device and method for measuring energy efficiency of transformer based on voltage difference value and current difference value | |
CN104237837A (en) | Current transformer ratio error and angle error detection system and method | |
CN202075405U (en) | Onsite overall detection system of three-phase electric energy metering system of distribution network | |
CN203949993U (en) | A kind of device based on voltage difference and electric current difference measuring transformer efficiency | |
CN202041592U (en) | Special vehicle-mounted test system for measuring key parameters of large-sized transformer | |
CN106501754B (en) | Test device for direct current and even harmonic influence quantity of three-phase electric energy meter | |
CN106959427A (en) | A kind of anti-DC performance hanging net operation verification experimental verification method of electric power meter | |
CN108152782B (en) | Method for testing correction coefficient of high-supply high-count electric energy meter | |
CN103293374A (en) | Three-phase access type electric energy meter with electronic transformers and metering method for three phase access type electric energy meter | |
CN202929193U (en) | Integrated error verification system for electric energy meter | |
CN206074797U (en) | The assay device of the direct current and even-order harmonic influence amount of three-phase electric energy meter | |
CN107490721A (en) | A kind of intelligent electric meter electric power meter based on NB IoT | |
CN207248993U (en) | A kind of intelligent electric meter electric energy metering device based on NB IoT | |
CN107843866A (en) | Examine and determine the connection circuit and method for the distribution transformer that three-phase and four-line neutral point is extracted out | |
CN204631238U (en) | A kind of large direct current measuring device ripple response performance test macro |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
CF01 | Termination of patent right due to non-payment of annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141119 Termination date: 20160714 |