Current isolation mutual inductor

Abstract

The invention discloses a current isolation mutual inductor. The current isolation mutual inductor comprises a mutual inductor shell used for avoiding external signal interference, a permalloy iron core I, a permalloy iron core II, and a winding W1, a winding W2, a winding W3, a winding W4 and a winding W5 of the permalloy iron core I and the permalloy iron core II. The current isolation mutual inductor further comprises an electronic compensating circuit used for compensating for the magnetic potential. The permalloy iron cores, the windings of the permalloy iron cores and the electronic compensating circuit are arranged in the mutual inductor shell. The electronic compensating circuit comprises a power module, an operational amplifier circuit, an open circuit detection circuit and an alarm circuit. The current isolation mutual inductor has the advantages that detection of a three-phase direct access type electricity meter can be completed when a three-phase assembly line and a three-phase equipotential calibration device are not unhooked or can not be unhooked in the calibration process, the current isolation mutual inductor is simple in overall structure and elegant and attractive in appearance, line outgoing and line incoming are standard, the current input and output wiring mode is simple and reliable, and the current isolation mutual inductor is convenient to use.

Description

technical field [0001] The invention relates to the field of automatic calibration systems for single-phase and three-phase electric energy meter assembly lines, in particular to a current isolation transformer. Background technique [0002] In order to ensure the safe and economical operation of the power system, it is necessary to monitor and measure the operation of the power equipment, but the general measurement and protection devices cannot be directly connected to the primary high-voltage equipment, but need to convert the large current of the primary system into a small current in proportion. It is used for measuring instruments and protection devices, which requires the use of current transformers. The current transformers play the role of current conversion and electrical isolation. It is the secondary equipment such as measuring instruments and relay protection in the power system to obtain the electrical primary circuit current. Information sensors, current trans...

AI Technical Summary

Problems solved by technology

At present, the three-phase assembly line cannot decouple the voltage and current when calibrating the direct-connected meter (State Grid Corporation plans to launch a three-phase direct-connected meter without an external voltage connection piece, so it cannot be decoupled), so an isolated CT must be used. Calibration, the current technical status is that the isolation CT is unreasonable in the structure of the lead wire, which makes it particularly inconvenient to install the transformer on the device and affects the appearance

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