An operating method for correct short-circuiting of current loops in busbar protection maintenance

Abstract

The invention provides a correct short-circuiting operation method for current loops in busbar protection maintenance, which includes first controlling the busbar protection connecting piece on the busbar protection screen to exit the state; secondly determining the short-circuiting sequence of the interval current transformers; and then, according to the short-circuit In sequence, after short-circuiting the four secondary side terminals of the busbar protection screen terminal strip corresponding to each bay current transformer to the ground, disconnect the four connecting pieces on the corresponding busbar protection screen terminal strip one by one and determine before and after the disconnection. Whether the current value changes, if so, adjust it until the current value of the four corresponding connecting pieces does not change before and after disconnection; finally, you can wait to enter the busbar protection inspection and maintenance work. Implementing the present invention can overcome accidents such as personal electric shock or failure-free tripping of the busbar protection screen caused by improper current loop short-circuit operating methods in the prior art, and has higher safety and reliability.

Description

technical field [0001] The invention relates to the technical field of substation maintenance, in particular to an operation method for correct short-circuiting of a current loop during busbar protection maintenance. Background technique [0002] Busbar protection inspection and maintenance is to isolate only the busbar protection that needs to be inspected and maintained during the continuous operation of the primary equipment of the power grid. However, due to the continuous operation of the primary equipment of the power grid, the secondary circuit of the interval current connected to the bus protection screen is still in normal operation. Therefore, it is necessary to short-circuit the current secondary circuit during the maintenance of the bus protection to avoid secondary side current The flow into the busbar protection screen will affect the busbar protection inspection and maintenance work. However, maintenance personnel, especially novices, during the short-circuit...

AI Technical Summary

Problems solved by technology

If there is a problem with the short circuit between phase A and phase N, there is an open circuit in phase A, so that the interval 1 current transformer generates a high instantaneous voltage at both ends of the secondary winding of phase A, which can easily cause personal electric shock and other accidents

[0004] For another example, before the on-site staff short-circuits the secondary side A phase, B phase, C phase and N phase of the current transformer at interval 1, directly disconnect the secondary side of the current transformer corresponding to interval 1 on the terminal block of the bus protection screen. The connection piece of any one of the A phase, B phase and C phase on the secondary side makes the current entering the bus protection screen not a three-phase balanced current, which may easily cause the bus protection connection piece of the bus protection screen to trip under no fault conditions. Thus greatly affecting the busbar protection maintenance work

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