The Xiang-Shang ±800kV UHVDC pilot transmission project is the most powerful HVDC link in the World and the first one of a row of other similar projects in China for the following development of a 800kV HVDC energy transmission corridor from West to East to bring the bulk power generated in the areas rich of primary resources (hydro and coal) to the areas with the major load demand. The quality in design and manufacturing of the corresponding key equipment of the HVDC Converter Stations is the basic requirement to assure the required reliability in the operation of the pilot line as well as of the future developments.
What we have done
Quality Assurance services during the manufacturing process of:
- Seven converter transformer units for Yinchuandong station and four converter transformer units for Qingdao station made by ABB – Ludvika (Sweden).
- One YY and YΔ converter transformer unit for Qingdao converter station made by Xibian – Xi'An (P.R.C.) and one YY and YΔ converter transformer unit for Qingdao converter station made by Shenbian – Shenyang (P.R.C.).
The whole QA services dealt with:
- Design review (design of transformers and reactors reviewed by means of dedicated missions at manufacturer's premises by checking of all documents relevant to the design, as well as technical specifications and foreseen tests);
- Qualification of the manufacturers (analysis of the quality system of the companies, and in particular of the quality manual and related procedures, work instructions, quality control plans. The activity performed by means of a deep analysis of the documentation and meetings/interviews with the involved Company managers);
- Pre-inspection of production lines and of test laboratories (workshops and laboratories inspected with the aim at assessing Company's capabilities);
- In-production inspections (supervision of the whole manufacturing process of transformers and reactors monitored by means of phased inspections of key parts like, e.g. winding and core manufacturing, drying process, tank manufacturing, final assembling; stores and incoming materials also checked as well as sub-suppliers workshops);
- Witnessing to type and routine tests of transformers and reactors (type and routine tests of transformers and reactors: all type and routine tests witnessed by highly skilled inspectors).
The excellent supervision service provided by CESI allowed pinpointing several nonconformities during the design and manufacturing of the converter transformers which could be smoothly and successfully solved also thank you to the advices which CESI could providee to the involved Manufactures. In-factory testing was also carried out perfectly in compliance with the test requirements thanks you to Cesi detailed and careful inspections during such activites.