Transformer substation-dispatching center two-stage distribution type restoration control method

Abstract

The invention relates to a transformer substation-dispatching center two-stage distribution type restoration control method and belongs to the field of dispatching automation technology in an electric power system. In the method, a control model for spare power source automatic switching of an electric network source is respectively established in a transformer substation and an electric network dispatching center; switch actions in the models are simulated in the dispatching center by a certain cycle and an alarm is given to a spare power source automatic switch which is subjected to overload at a standby power supply side; by judging a monitoring signal between a total automation system and an energy management system, the transformer substation determines different control modes; if the communication is interrupted or reliable, the model of local control is adopted; and if the communication is reliable, the model of transformer substation-dispatching center two-stage control is adopted. By the method, no device needs to be installed in the transformer station and maintained, thereby greatly lowering the investment cost, ensuring the correction of the action of spare power source automatic switching and improving the overall safety operation level of the electric network source.

Description

technical field [0001] The invention relates to a substation-dispatching center two-level distributed recovery control method, which belongs to the technical field of power system dispatching automation. Background technique [0002] The automatic switching device of the backup power supply of the power system, or referred to as standby automatic switching, is an important measure to improve the safety and reliable operation of the power grid, and is an important method for the power grid to achieve recovery control. When the working power fails to supply power due to failure, the automatic device should be able to quickly put the backup power into use automatically or switch the user to the backup power. Typical backup self-switching includes single-bus incoming line backup, section circuit breaker backup, transformer backup, incoming line and bridge backup, bypass circuit breaker backup, etc. [0003] At present, the widely used standby automatic switching device is a sta...

AI Technical Summary

Problems solved by technology

[0004] (1) High cost and high maintenance cost

The overall investment cost is high due to the need to install automatic switching devices at each substation

In addition, the devices are scattered in various substations and require regular maintenance, so maintenance costs are high

[0005] (2) The backup self-switching strategy of the standby automatic switching device cannot consider the safety of the remote backup power supply side equipment

The standby automatic switching device can only consider the local substation bus voltage or incoming line current, but cannot consider the capacity-load ratio of the main transformer on the remote standby power supply side, the thermal stability limit of the line, etc., which will easily lead to overload tripping on the standby power supply side, resulting in failure expand further

[0006] (3) The standby automatic switching strategy of the standby automatic switching device cannot be coordinated with the safety control device

However, practice shows that this method also has certain limitations:

In the process of information collection and instruction issuance, if the communication is interrupted or abnormal, the action strategy of the standby automatic switch will be affected

[0010] (3) Centralized backup and automatic switching uses the SCADA system to collect remote signaling and telemetry data as criteria, and then issues instructions through remote control after forming a strategy. There is a delay in the process of data collection and command issuance, which will cause backup and automatic switching. action delay

In addition, the accuracy of the data in the collection process will also affect the action strategy of the standby self-injection

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