A phase voltammeter for measuring small loads in parallel with current transformer loads

Abstract

The invention relates to a phase voltammeter for measuring small loads in parallel with current transformer loads. Multiple high-precision resistors are connected in parallel to the secondary load of the measured current transformer, and the premise is to ensure that the secondary circuit of the measured current transformer is not open. By converting small current signals into voltage signals, the protection phasor of high-voltage power equipment can be measured under small loads, which solves the problem that a large number of loads need to be organized for phasor measurement when high-voltage power equipment is charged for the first time. The correctness of the protection phasor can be checked under the load condition that is far less than 10% of the conventional required load, and the secondary load of the current transformer can be measured with the load, so that the equipment can be put into operation early. It can not only avoid easy damage to equipment caused by unadjusted load equipment, but also reduce idling equipment, save a lot of electric energy, and ensure the safe operation of the power grid. It can be widely used in the inspection of differential protection phasors of transformers or lines.

Description

technical field [0001] The invention relates to a phase voltammeter for measuring a small load in parallel with a current transformer load, in particular to a phase voltammeter for measuring a small load in parallel with a current transformer load that does not need a clamp. Background technique [0002] When a newly built load transformer or line is put into operation for the first time, such as when a large power plant standby / startup transformer or a new factory or mine transformer is charged for the first time, it is necessary to check the differential protection phasor with a heavy load immediately after the high voltage power equipment is charged. The primary equipment and its main protection can only be put into operation after the protection and meter phasors are correct. The current instrument for measuring phasor is a clamp-type volt-ampere phase meter. The measurement of the current is done by means of pliers that induce a magnetic field. In theory, the minimum v...

AI Technical Summary

Problems solved by technology

[0004] However, it is difficult for newly-built high-voltage power equipment to carry a large load immediately after it is charged for the first time. Usually, a large number of electrical driving equipment (loads) are being installed or have not been debugged because there is no power supply at this time.

At this time, if a large number of electrical driving equipment is organized to rotate without commissioning, it will not only easily cause equipment damage accidents, but also consume a large amount of electric energy due to idling, and may also cause electrical equipment accidents and affect the safety of the power system.

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