A fully intelligent current transformer with insulation and error self-inspection

Abstract

The invention provides an insulated and error self-inspecting type full-intelligent current transformer which integrates a transformer and a monitoring instrument and does not need any outside power supply, belongs to the field of high-voltage appliances, and applies to various capacitive type current transformers. The insulated and error self-inspecting type full-intelligent current transformer is characterized in that a hollow coil is adopted, so that the problem that a standard coil is checked after power supply is cut off can be solved; energy is extracted from a low-voltage capacitor of a capacitive voltage-sharing insolating core body in order to supply power to the monitoring instrument, and thus the problem of arranging the outside power supply is solved. The insulated and error self-inspecting type full-intelligent current transformer has the advantages that the measuring and protecting functions can be performed without cutting off the power supply; the capacitance current and system voltage of the current transformer, the error of a measuring winding and a protecting winding, and various information related to the current magnitude, phase and system voltage can be displayed, recorded and output or directly uploaded to the network on line and on real time at the same time; any puncturing of some insulating layer or excessive error of a primary winding can be warmed in advance in order to prevent the current transformer from accident.

Description

technical field [0001] This patent belongs to the field of high-voltage electrical appliances and relates to various current transformers with capacitive insulation. Background technique [0002] The current transformer is a sensor for secondary equipment such as measuring instruments and relay protection in the power system to obtain the current information of the primary circuit. functions. Whether the current transformer itself works normally or not is of great significance to the safety of the power system and the normal operation of protection, measurement and other equipment. [0003] The primary winding of the current capacitive current transformer is a capacitive insulating core. Its basic structure is to alternately wrap the insulating layer around the conductor and the capacitive screen, and the last layer of capacitive screen is grounded to form a capacitive voltage equalizing insulating core. The secondary winding, including the measuring winding and the protec...

AI Technical Summary

Problems solved by technology

[0009] However, there is still a problem in the technical scheme of "on-line detection method of current transformer error", that is, the standard coil used to verify the secondary winding error of the current transformer is also an iron core coil. The performance of the core will also change and become not "standard" enough, and power failure detection and verification are also required

[0010] In addition, the patent 201210051917.5 "on-line detection method of current transformer error" also needs an external power supply, which is not convenient enough

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