Wide metering current transformer

Abstract

The invention discloses a wide metering current transformer which comprises large and small transformation ratio current transformers and a wide metering transformation terminal. The large and small transformation ratio current transformers are arranged on a same-phase bus, and mechanical connection and electric isolation are achieved through resin cast between the large and small transformation ratio current transformers. The wide metering transformation terminal is composed of a current transformer switching unit and a control device. The current transformer switching unit comprises a transformation ratio transformation current transformer, a CT switching detection current transformer, and controllable switch devices used for switching two dual-transformation ratio bus side current transformers. The first and second controllable switch devices are connected with a control device. The control device is used for controlling on and off of the first and second controllable switch devices through programs, and the control device is connected with a power source. Electric transformers with different transformation ratios can be automatically switched, the integration degree is high, controlled silicon is adopted for current transformation contacts, action is made reliable and convenient, and the problem that a fault is caused when an electromagnetic relay frequently acts to burn out a contact is avoided.

Description

technical field [0001] The invention relates to a wide-width metering current transformer. Background technique [0002] Before new equipment is put into use, it is necessary to test the equipment in order to verify the performance of the equipment, especially the safety performance and working performance of the equipment must be guaranteed. 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. However, 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 to supply the measuring instruments and protection devices. [0003] In every link of the power system, including power generation, power transformation, power transmission, power distribution and power consumption, it is necessary to measure, protect and control the line (her...

AI Technical Summary

Problems solved by technology

[0008] It can be seen that the above schemes and their existing technologies all take remedial measures for the secondary open circuit of the current transformer after the event, and fail to fundamentally solve the problem

[0009] At the same time, the current transformers with different sizes and multiple ratios used for accurate measurement are not highly intelligent, and the transfer contacts are easily damaged, which is not ideal and practical.

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