Device for improving secondary load of voltage transformer

Abstract

The invention relates to the technical field of metering voltage transformers in a power system, and especially relates to a device for improving a secondary load of a voltage transformer, specifically a device for improving the secondary load of a voltage transformer for a three-phase three-line electric energy meter. The device comprises a detected voltage transformer, a standard voltage transformer, and a transformer calibrator. The load improving the device is connected in parallel in a secondary loop of the detected voltage transformer, and the measurement of the rated value and a lower limit value are carried out through the on / off adjustment of the load improving device. The secondary terminals of the standard voltage transformer and the detected voltage transformer are connected with the transformer calibrator. The system can effectively solve a problem of error measurement of the voltage transformer for the three-phase three-line electric energy meter, can be used for replacing a conventional verification voltage transformer load box, is directly connected in the secondary loop of the detected voltage transformer in a parallel manner, is different from a voltage transformer load box, and does not need to be disassembled. The device is simple in structure, is low in cost, is easy to implement, and does not need to carry the voltage transformer load box.

Description

technical field [0001] The invention relates to the technical field of voltage transformers for metering in power systems, in particular to a secondary load improvement device for voltage transformers, in particular to a secondary load improvement device for voltage transformers for three-phase three-wire electric energy meters. Background technique [0002] According to the requirements of JJG 314-2010 "Verification Regulations for Measuring Voltage Transformers", when performing error verification on voltage transformers, it is necessary to evaluate the secondary load rating and lower limit value separately. The traditional verification method is to connect a voltage transformer load box in parallel in the secondary circuit of the tested voltage transformer, and dial the load box to the corresponding value to measure the rated value and lower limit value. However, for the standard voltage transformer of the power system, the secondary rated load is generally 0.07VA, and th...

AI Technical Summary

Problems solved by technology

However, for the standard voltage transformer of the power system, the secondary rated load is generally 0.07VA, and the minimum range of the voltage transformer load box is 1.25VA, which cannot meet the measurement of the rated value. Usually, the rated value is equal to the lower limit 0VA measurement, neither the rated value and the lower limit value are distinguished, but also the error of the voltage transformer when the rated value is increased

Images