Intertripping small power supply device and intertripping method applied to intelligent substation

Abstract

The invention discloses an intertripping small power supply device and intertripping method applied to an intelligent substation. The intertripping small power supply device comprises an optical inputunit module, a CPU module, a logic judgment module, a hard contact input module, an execution module and a communication module, wherein an input end of the optical input unit module is connected with a line protection device, a first automatic bus transfer device, a main transformer zero-sequence protection device and a second automatic bus transfer device separately; and the line protection device comprises a voltage detection module, a current detection module, a temperature detection module, a data processing module, a judgment and comparison module and a decision-making module. Accordingto the intertripping small power supply device and intertripping method applied to the intelligent substation, the complexity of construction transformation is simplified, the design and constructionefficiency is improved, future expansion and daily maintenance are facilitated, the problem that intertripping small power supplies for the intelligent substation are difficult to implement is effectively solved and the intertripping small power supply device and the intertripping method have a good application prospect in the technical fields of relay protection and automation of a power system.

Description

technical field [0001] The invention relates to the technical field of power system relay protection and its automation, in particular to a combined-cutting small power supply device and a combined-cutting method applied to an intelligent substation. Background technique [0002] With the development of new energy sources such as wind power, photovoltaics, and biomass power generation, a large amount of new energy needs to be connected to substations. Action, the action of the main transformer zero sequence protection device, the action of the 110kV backup self-turning device, and the action of the 10kV backup self-turning device all need to cut off the small power supply before the line reclosing or the correct action of the backup self-turning device can be realized, and the power supply can be restored in time to ensure Safe and stable operation of the power grid system. [0003] With the large-scale construction of intelligent substations of State Grid Corporation of Ch...

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Problems solved by technology

[0004] At present, the common practice of smart substation to cut small power supply is to connect 110kV line protection, main transformer zero-sequence protection, 110kV standby self-injection device, and 10kV standby self-injection device to the intelligent terminal on the low-voltage side of the main transformer through optical cables, 110kV line protection, etc. The digital device transmits the tripping GOOSE signal to the intelligent terminal on the low-voltage side of the main transformer through an optical cable. In the tripping circuit of the small power supply interval line protection operation box to realize the joint cut function of the small power supply, but due to the limited output contacts of the intelligent terminal on the low-voltage side of the main transformer in the smart substation, if multiple small power supplies are connected to the 10kV bus, the main The intelligent terminal on the low-voltage side of the transformer cannot meet the requirements for the number of outgoing contacts. At the same time, due to the limited space in the secondary small room of the switchgear on the low-voltage side of the main transformer, the optical fiber distribution frame configured in the early stage often cannot meet the requirements for the fusion splicing position of the newly added optical cable for small power supply. As a result, the transformation of the switchgear during construction is complicated or even difficult to implement, causing certain difficulties in both design and construction. In addition, because the intelligent terminal does not have the function of logical judgment, it is impossible to carry out the strategy of connecting and cutting small power sources according to the position of the 110kV bus tie switch and the position of the 10kV segment Judgment makes the joint cut of small power sources non-selective, which brings hidden dangers to the safe operation of the power grid

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