CN2685896Y

CN2685896Y - High precision electronic current lift for electric energy meter checking equipment

Info

Publication number: CN2685896Y
Application number: CN 200320107927
Authority: CN
Inventors: 高其能
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-11-06
Filing date: 2003-11-06
Publication date: 2005-03-16
Anticipated expiration: 2013-11-06

Abstract

The utility model discloses a high precision electronic current lift for electric energy meter checking device, comprising a main current lifting device T1, a measuring mutual-inductor T2, T3, a signal detection magnification compensation loop, and a fault or anomaly detecting loop. The main current lifting device T1 is provided with two once external input current ends and the secondary current output ends. Every secondary current output end is respectively connected with two total output ends of the main current lifting device. The signal amplification and the electric compensation loop are connected by a signal power amplifier A3, A4, and a compensating coil. The fault or anomaly detecting circuit is connected with an AD-DC switching circuit A2, an amplifier A1, a triggering latch, and a reset key. Adopting the current lift checking device of the utility model, N electric energy meters can be simultaneously checked in batch size, which can degrade the current range ability of the standard electric energy and use the standard electric energy meter with single measuring range for the convenience of checking meter work. When checking, each three-phase electric energy meter is matched with an independent current lifting device, which can eliminate the mutual effect to guarantee the accuracy of the checking.

Description

Electric energy meter checking device high-precision electronic current lifting device

Technical field the utility model relates to the electronic current lift of using on a kind of electric energy meter checking device.

Background technology is along with fast development of national economy and living standards of the people improves constantly, power consumption also increases sharply, to electric energy tariff and anti-electricity-theft having higher requirement, electric current and voltage loop and the electric energy meter (also claiming not take off hooklet) that connects produce thereupon, and this has just proposed corresponding requirement to electric energy meter checking device.The existing multichannel isolation boosting device that adopts comes a plurality of single-phase electric energy meters that do not take off hooklet of verification simultaneously in the single-phase electric energy meter calibration equipment at present.But the three-phase floating potential of three characteristics of the middle term multichannel isolation boosting device output is difficult to stablize to the phase differential of three-phase current, can not guarantee the composition error of electric energy meter checking device and limit its application, for not taking off the hooklet three-phase electric energy meter, at present still to carry out the single master that is verified as.Because when the hooklet three-phase electric energy meter is not taken off in the batch verification, the voltage circuit of all electric energy meters also connects, the necessary coupled in series of its current return, and the I1 of a last table is connected to the Ih end of next table.Like this, when Uh and Ih short circuit, in fact also all Ih have been held short circuit, just the Ih of each table end and I1 have been held short circuit in (except last piece table), thereby influenced the normal operating conditions of tested electric energy meter, also just can not carry out normal verification electric energy meter.

The summary of the invention technical problem to be solved in the utility model is to propose a kind ofly can carry out the electric energy meter checking device high-precision electronic current lifting device of verification in batches to not taking off the hooklet three-phase electric energy meter.

For solving the problems of the technologies described above, the utility model electric energy meter checking device comprises main current lifting device T1 with the high-precision electronic current lifting device, measure mutual inductor T2, T3, input is amplified equalizing network, fault or abnormality detection loop, main current lifting device T1 has two once outside input current ends and secondary current output terminal, each secondary current output terminal links to each other with two total output terminals of main current lifting device respectively, signal amplification and electronic compensation loop are by signal power amplifier A3, A4 and compensating coil are linked to be, error-detecting has been adopted the electric current differential method and has been converted voltage signal to by power amplifier A3, measure mutual inductor T2 and T3 and measure current lifting device respectively once with secondary current and be converted to little electric current, its difference between current is through power amplifier A3 sampling and amplification, output to compensating coil through power amplifier A4 again, fault or abnormal detection circuit are by AD-DC change-over circuit A2, amplifier A1, trigger latch U1A, reset keys etc. are formed by connecting.

Above-mentioned electric energy meter checking device high-precision electronic current lifting device, a total output terminal trigger latch U1A warp and door and driver U2 drive controlling relay S6 by pilot relay S6 control.

Above-mentioned electric energy meter checking device high-precision electronic current lifting device, each secondary current output terminal are all controlled its range by the range pilot relay and are changed.

Owing to adopted above-mentioned technical pattern, during verification, on N epi-position electric energy meter checking device, one secondary input end of N the utility model current lifting device and standard electric energy meter are connected in series the current output terminal that is connected to electric energy meter checking device again, the secondary output terminal of N current lifting device is connected to the current input terminal of N electric energy meter respectively, the voltage input end of the voltage input end of all electric energy and standard electric energy and be connected to the voltage output end (as shown in Figure 2) of electric energy meter checking device.Like this, when the Uh of each tested electric energy meter and Ih short circuit, the duty of each tested electric energy meter does not all have to change, calibration equipment is N electric energy meter of batch verification simultaneously, reduced the current range scope of standard electric energy, can use the standard electric energy meter of single range, reduce the cost of standard electric energy meter, make things convenient for calibration work.Because the utility model has adopted advanced electronic compensation technology, produces offset current with electron device, compensates the ratio error of its a secondary output current and an input current, in the loading range of regulation, make it less than 0.1% (composition error).At a plurality of three-phase electric energy meter voltage circuits and when connecing verification simultaneously, each three-phase electric energy meter is equipped with one overlaps independently current lifting device, make its current return independent fully mutually, the influence between having eliminated has mutually guaranteed the accuracy of verification.Pilot relay S6, with door and the setting up of driver U2, can make the electrical energy meter calibration meter apparatus possess the automatic arbitration functions of epi-position, when this epi-position is not hung electric energy meter, automatically this epi-position current return of short circuit can also reach the function of seeking rotating disc type electric energy meter rotating disk mark by the break-make of controlling this epi-position current return.

Description of drawings is described in further detail the utility model below in conjunction with drawings and embodiments.

Fig. 1 is the circuit catenation principle figure of the utility model current lifting device;

Fig. 2 is the wiring schematic diagram when adopting this reality that the electric energy meter checking device calibration of current lifting device is arranged.

Embodiment as shown in Figure 1, electric energy meter checking device comprises main current lifting device T1 with the high-precision electronic current lifting device, measure mutual inductor T2, T3, input is amplified equalizing network, fault or abnormality detection loop, main current lifting device T1 has two once outside input current end Port1 and Port2, and 0.1A, 1A, 10A, five secondary current output terminals (secondary output current value and range can be determined as requested separately) such as 100A and L end, T1 once should be with once equal fully with the electric current product of secondary (promptly once with the ampere turns of secondary) with the coil turn of secondary, 0.1A, 1A, 10A, four secondary current output terminals such as 100A are controlled its range by range pilot relay S2～S5 respectively and are changed, Port6～Port9 is the range switch-over control signal, is outputted to the range that needs with handle.Port3 and Port4 are current lifting device two total output terminals, are connected to the current input terminal of tested electric energy meter.L end secondary current output terminal links to each other with Port3 by a switch, and all the other each secondary current output terminals link to each other with Port4 by on ﹠ off switch respectively, and total output terminal Port3 is used to switch on or off the electric energy meter electric current by pilot relay S6 control.The signal amplifying return circuit is formed by connecting by signal amplifier A3 and A4, resistance R 3～R6, T2 and T3 measure current lifting device respectively once with secondary current and be converted to little electric current, difference between current after both subtract each other is through A3 sampling and amplification, output to compensating coil through power amplifier A4 again, the ratio and the angular difference of compensation current lifting device secondary current and primary current.Generally speaking, if the compensation amplification coefficient is N times of difference between current, then ratio between first and second electric current and angular difference will be reduced to about original 1/N.But amplification coefficient can not be too big, otherwise will cause self-sustained oscillation.Compensation amplification coefficient as current lifting device is 100 times, and the comprehensive error code of this current lifting device first and second electric current poor (ratio and angular difference) can be less than 0.1%.Fault or abnormal detection circuit are formed by connecting by AD-DC change-over circuit A2, amplifier A1, triggering latch U1A, reset key S1, electric current output (or fault) pilot lamp D1 and resistance R 1, R2.A2 is converted to direct current measurement (voltage) with compensation rate by ac electric, compare with predetermined threshold voltage UR, when current lifting device second open circuit (not connecing table) or load is excessive when exceeding compensation range, the compensation output voltage will be bigger, after the A2 conversion, as surpassing threshold voltage, then trigger latch U1A (U1A can adopt d type flip flop or other type flip-flop), and through cutting off the extrinsic current output loop with door and driver U2 drive controlling relay S6, and short circuit current lifting device secondary circuit, with the operate as normal that guarantees whole meter correcting system (promptly when this current lifting device second open circuit, will cause that the whole current return of meter correcting system is undesired).S1 is a reset switch, after fault is got rid of, clicks S1, and U1A is resetted, thereby current lifting device is recovered by Port3 and the external output current of Port4.D1 is electric current output (or fault) pilot lamp, represents to cut off output when bright, recovers output when dark.Port5 is a system or foreign current output control signal, the walking (turn-on current) or stop (cut-out electric current) of may command electric energy meter.When need were located induction type table rotating disk, system detected turntable sheet by photoelectric sampler and clocks, and can control current lifting device by Port5 and cut off the electric energy meter electric current, made electric energy meter stop walking.

Claims

1, electric energy meter checking device high-precision electronic current lifting device, comprise main current lifting device T1, it is characterized in that, it also includes measures mutual inductor T2, T3, input is amplified equalizing network, fault or abnormality detection loop, described main current lifting device T1 has two once outside input current ends and secondary current output terminal, each described secondary current output terminal links to each other with two total output terminals of described main current lifting device respectively, described signal amplification and electronic compensation loop are by signal power amplifier A3, A4 and compensating coil are linked to be, described error-detecting has been adopted the electric current differential method and has been converted voltage signal to by power amplifier A3, described measurement mutual inductor T2 and T3 measure current lifting device respectively once with secondary current and be converted to little electric current, its difference between current is through power amplifier A3 sampling and amplification, output to described compensating coil through power amplifier A4 again, described fault or abnormal detection circuit are by AD-DC change-over circuit A2, amplifier A1, trigger latch U1A, reset keys etc. are formed by connecting.

2, electric energy meter checking device as claimed in claim 1 high-precision electronic current lifting device, it is characterized in that, described one total output terminal is controlled by pilot relay S6, described triggering latch U1A is through driving described pilot relay S6 with door and driver U2, also can be by external signal by Port5 pilot relay S6, with the electric current output of control electronic current lift.

3, electric energy meter checking device as claimed in claim 1 or 2 high-precision electronic current lifting device is characterized in that, described each secondary current output terminal is all controlled its range by the range pilot relay and changed.