Judgment method for misconnection of three-phase three-wire electric energy meter

Abstract

The invention discloses a judgment method for misconnection of a three-phase three-wire electric energy meter, and belongs to the field of measurement. The method comprises the steps of determining whether connected relation of each connection terminal of a three-phase active electric energy meter or a three-phase reactive electric energy meter is correct according to the steering of the three-phase active electric energy meter and the three-phase reactive electric energy meter for a balanced and symmetrical three-phase load, conducting vector analysis according to actual connection, obtaining a calculation expression of actual active power and reactive power, and obtaining an influence of a metering error. A cause for a connection error can be found rapidly by conducting the vector analysis according to the actual connection and through the steering relation of the active electric energy meter and the reactive electric energy meter; the cause for the connection error can be judged by simple comparison; and the method is conveniently mastered by field staff and easy to popularize, and can be extensively used in the field of electric energy metering management.

Description

technical field [0001] The invention belongs to the field of measurement, in particular to a fault judgment method for electric energy meters. Background technique [0002] Since the general high-voltage systems of 10kV and above adopt the three-phase three-wire power supply mode, most high-voltage systems use three-phase two-element electric energy meters to measure electric energy. [0003] The wiring of the three-phase three-wire watt-hour meter is not very complicated. Due to negligence, especially the watt-hour meter with voltage transformer and current transformer, there are many chances of wrong connection. [0004] When the three-phase three-wire electric energy meter is wrongly connected, many strange phenomena occur: sometimes it does not turn, sometimes it reverses, sometimes it turns forward with the change of the load power factor angle, sometimes it turns reversely, and some of them turn forward, but the amount of electricity is different from the actual value....

AI Technical Summary

Problems solved by technology

[0003] The wiring of the three-phase three-wire watt-hour meter is not very complicated. Due to negligence, especially the watt-hour meter with voltage transformer and current transformer, there are many chances of wrong connection.

[0004] When the three-phase three-wire electric energy meter is wrongly connected, many strange phenomena occur: sometimes it does not turn, sometimes it reverses, sometimes it turns forward with the change of the load power factor angle, sometimes it turns reversely, and some of them turn forward, but the amount of electricity is different from the actual value. does not match

[0006] If the secondary line of the current transformer is wrongly connected, there are eight kinds of connections, one of which can measure electric energy correctly, two kinds of electric energy meters do not run, three kinds of electric energy meters reverse, and two kinds of electric energy meters turn forward, But the metered energy is wrong