Relay protection system of power transmission line containing current limiting reactor

Abstract

The invention discloses a relay protection system of a power transmission line containing a current limiting reactor. The relay protection system comprises a voltage transformer and a current transformer which are arranged on the two sides of an overhead line respectively. The voltage transformer and the current transformer are arranged on the side, not connected with the overhead line, of the two sides of the current limiting reactor; line protection devices integrated with a current-limiting reactor protection function are respectively configured on two sides of the whole power transmission line containing the current-limiting reactor; and after protection action of the circuit on one side, the circuit breaker on the side is tripped off, and the circuit breaker on the opposite side in parallel is tripped off. According to the system, only one-time system measuring points need to be added, a relay protection device does not need to be added, an original line protection constant value does not need to be changed, the protection range not only comprises an original overhead line, but also comprises the current-limiting reactor, and the system is suitable for two operation modes of input and quit of the current-limiting reactor.

Description

technical field [0001] The invention belongs to the field of relay protection for electric power systems, and relates to a relay protection system for transmission lines with current-limiting reactors. Background technique [0002] With the continuous development and expansion of the power grid, the electrical connection is getting closer and closer. The 500kV power grid sites in developed areas are densely distributed. The short-circuit current level of the main hub 500kV substation is constantly increasing. The short-circuit current of the 500kV bus in the substation is close to or exceeds the breaking capacity of the circuit breaker. It is urgent to limit the short-circuit current level. Adding a current-limiting reactor to the relevant 500kV line can effectively reduce the short-circuit current and at the same time have an impact on the power flow distribution of the power grid. [0003] The installation of current-limiting reactors on transmission lines can extend the ...

AI Technical Summary

Problems solved by technology

Chinese patent application number 200910034668.7, published on December 14, 2011, the name of the invention is a method for protecting the distance of a series capacitance compensation line combined with a phase-comparing relay. , its shortcoming is that it is only suitable for transmission lines where the series equipment is capacitive series equipment

The disadvantage is that the zero-sequence compensation coefficient is not easy to adjust

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