on April 2, the south grid energy storage repair and test company successfully completed the first circuit breaker protection and the overall replacement of short-lead protection devices in the 500kV switching station of Qingyuan pumped storage power station and the successful power transmission at one time, marking the completion of iterative upgrade of the 500kV high-voltage system protection equipment of Qingyuan power station and building a secondary defense line for the safe and stable operation of the power station.
the object of this transformation is 500kV circuit breaker protection and short-lead protection devices that have been in continuous operation for nearly 12 years. they not only ensure the safety of daily operation of the power station, it should also deal with the risk of special working conditions, which constitutes a “double insurance” for the stable operation of the 500kV high-voltage system of the pumped storage power station “. The renovation started on March 8, involving the replacement of 4 circuit breaker protection devices and 8 short-lead protection devices. The “screen-out renovation” method was adopted to complete the internal wiring replacement and secondary circuit reconstruction on the premise of not moving the protection screen cabinet. The construction period was short, the task was heavy, and the risk control requirements were high.
in order to ensure the safe and efficient progress of the renovation, the electrical secondary maintenance department of the repair and testing company has started the preliminary work of the renovation project, line sorting and scheme preparation since December last year. In view of the outstanding problem that the original design drawings are inconsistent with the site, the maintenance team relies on independent verification and drawing revision to re-form the construction drawings with consistent drawings and facts, so as to avoid wiring errors and safety risks from the source. In view of the difficulties of numerous circuit circuits and vague identification of some lines, the maintenance team strictly implements “double monitoring, single operation and root-by-root recording” in unwiring. Through multiple verification methods such as insulation test, cross-side linkage test, potential measurement without wire removal, short circuit test, etc., the bottom line of safety and quality is strictly adhered to throughout the whole process to ensure zero errors and hidden dangers in the renovation process.
After 26 days of continuous struggle, the renovation project was successfully completed. After the replacement of the circuit breaker protection and short lead protection device, the sampling accuracy, action speed and anti-interference ability all meet the requirements of the latest countermeasures, which effectively improves the operation reliability of the 500kV system of the clean storage power station. The renovation also allows new employees to participate in the secondary line removal, screen cabinet wiring, function verification and other links through the mode of “teacher with apprentice and teacher with help”. The rapid growth from “understanding theory” to “practical operation” has been realized in practical experience, which has effectively strengthened the company’s echelon of maintenance professionals and provided a solid guarantee for the safe and stable operation of the power station.
