The electrical control system of the 1260T·M extra – large floor – mounted twin – flat – boom derrick uses three sets of Mitsubishi PLCs for 485 communication, and Mitsubishi frequency converters are adopted for each mechanism. The complete set of electrical control cabinets is made of stainless steel, featuring high cost – effectiveness, stable product performance, and resistance to salt – fog corrosion. It is applied in the Zhenhai – Zhoushan 500 kV interconnection power transmission and transformation project.
This project has an investment of 4.62 billion yuan. It is by far the 500 kV cross – regional and cross – sea interconnection project with the largest investment and the highest construction difficulty in the Zhejiang Power Grid. The project construction will face two major challenges and also set two new world records. Firstly, the construction of two 380 – meter – high towers. Currently, the world record for the tallest transmission towers is held by two towers in the Ningbo – Zhoushan 220 kV interconnection project located on Damao Island and Liangmao Island, with a height of 370 meters. For the newly started second interconnection channel, two 380 – meter – high transmission towers will be built on Jintang Island and Cezi Island respectively, breaking the world record for the height of transmission towers. Secondly, the laying of submarine cables. The approximately 17 – kilometer – long submarine cable newly laid from Zhenhai, Ningbo to Dapeng Island, Zhoushan will use domestically – produced 500 kV cross – linked polyethylene submarine cables. This is the world’s first alternating – current 500 kV polyethylene – insulated submarine cable project, independently developed and manufactured by China. Relying on the Zhoushan 500 kV interconnection power transmission and transformation project to accelerate the research on submarine cable and ultra – high crossing tower technologies and solve a series of construction and installation problems is of great significance for promoting the development of marine power transmission technologies and is also another strong proof of the rise of Chinese manufacturing.
This project will break two world records, namely building two 380 – meter – high world – leading transmission towers and using the world’s first domestically – produced 500 kV cross – linked polyethylene submarine cable. In the near future, a continuous supply of electricity will provide a powerful power engine for the development of the Zhoushan New Area, strongly promoting the development of the Zhoushan Archipelago New Area and boosting the construction of the “Belt and Road”.