Test device for testing direct current and even harmonic influence quantity of electric energy meter

Abstract

The invention provides a test device for testing the direct current and even harmonic influence quantity of an electric energy meter. The test device is characterized by comprising the electric energy meter, an electric energy meter calibrating device for testing the electric energy metering precision of the electric energy meter and a direct-current current source for outputting direct-current current from a current loop of the electric energy meter, wherein a voltage loop and the current loop of the electric energy meter are connected with a voltage loop and a current loop of the electric energy meter calibrating device, the electric energy pulse output of the electric energy meter is connected to the electric energy pulse test input end of the electric energy meter calibrating device, the output positive end of the direct-current current source is connected to the current leading-out wire end of the current loop of the electric energy meter, the output negative end of the direct-current current source is connected to the current incoming wire end of the current loop of the electric energy meter, and the test of the direct current and even harmonic influence quantity of the electric energy meter can be finished without dividing the current test loop into two current branches. Two diodes and one balanced impeder in the current test loop are omitted.

Description

technical field [0001] The invention relates to the technical field of electric energy measurement, in particular to a test device for testing the influence of direct current and even harmonics of an electric energy meter. Background technique [0002] In the power system, due to the extensive use of power electronic devices, especially the use of half-wave rectification equipment, half-wave current appears in the power line, generating DC power components, and when there is DC current in the current loop of the electric energy meter, The magnetic properties of the magnetic core of the electromagnetic current transformer of the electric energy meter will be degraded or even saturated, so that the electromagnetic current transformer of the electric energy meter cannot be measured accurately, which will affect the accuracy of the electric energy measurement of the electric energy meter. Therefore, the electric energy meter is required The electromagnetic current transformer in...

AI Technical Summary

Problems solved by technology

[0005] In the existing measurement technology scheme, in order to test the influence of DC and even harmonics of the electric energy meter, the current measurement circuit needs to be divided into two current branches, and in order to prevent the measurement results from being affected by the unbalanced load of the two branches, The impedance of the two current branches is required to be equal, which increases the complexity of testing the influence of DC and even harmonics on the energy meter

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