Under the cross-sea bridge connecting Beilun District of Ningbo and Meishan Island Free Trade Zone in Zhejiang Province, six "electric silver snakes" meander along the bridge towards the Meishan Island Port Area. In June this year, with the commissioning of the 110 kV Qijiang power transmission and transformation project, this cross-sea power channel will send a steady stream of power to the port area.

In 2008, the State Council approved the establishment of Ningbo Meishan Bonded Port Zone, which is China's fifth bonded port area after Shanghai Yangshan, Tianjin Dongjiang, Dalian Dayao Bay and Hainan Yangpu, and in the same year, the Ningbo Municipal Party Committee and Municipal Government made a decision to accelerate the construction of Meishan Island.

In September 2009, the construction of the speed known as "Meishan" was fully launched on the island, more than 400 mu of storage land began to be piled, more than 10 infrastructure projects were started, and the only 35 kV Meishan on the island was in short supply, and power construction was urgent. To this end, Ningbo Electricity Bureau adheres to the principle of special affairs and special affairs, and implements a special plan for power construction tailored for Meishan Island to meet the long-term development needs of the port area.

Tailor-made island "power accelerator"

Special power construction means that every link from feasibility study, design to construction will closely focus on the construction and development needs of the port area, which means more comprehensive, more meticulous and more intimate construction and services. At the beginning of 2013, after nearly five years of efforts, the 110 kV seven-surnamed power transmission and transformation project entered the stage of construction. In the face of such a rapidly developing island, protecting the environment and saving resources has become a task that Ningbo Electric Power Bureau must do in every possible way.

"Considering the long-term development environment of Meishan Island port area, the overhead lines in this area are undergoing "up and down" transformation. The person in charge of project design said. From the perspective of the long-term development of the port area, the conventional overhead line is bound to have an impact on the landscape of the Meishan Bridge gateway and the future development and construction of the area through which the line passes.

To this end, Ningbo Electricity Bureau planned ahead, on the one hand, to transform the overhead lines in the development area into the ground; On the one hand, a 110 kV cable with a cross-section of 1,000 square millimeters is used for extremely difficult cross-sea laying, and the "regional quality" of Meishan Island is improved with technical quality.

"In order to match the development of the island and combine the load characteristics of the port area, we chose the voltage level of the port distribution network to be 20 kV." The person in charge of the project design said that the distribution station project of Qixian power transmission and transformation on Meishan Island is currently under construction.

Previously, in order to save island resources and achieve the best power quality, Ningbo Electricity Bureau mobilized technical forces, expanded the scope of investigation, increased research efforts, fully combined with the characteristics of Meishan Island "long from east to west, narrow north to south", proposed to build a 20 kV smart distribution network on Meishan Island, and reduced the number of 110 kV substations planned on the island from 3 to 2, saving line channel resources and land resources to the greatest extent.

Cross-sea laying of "energy artery" in port area

In April, the transmission line project from 220 kV Xianxiang Ganao Line T to 110 kV Seven Surname Transformation entered the most critical cross-sea cable laying stage of the entire project. This short 1.1 km carries the three firsts of Ningbo's 110 kV cable: the first cable laying with a cross-section of 1000 square millimeters, the first cable construction with the cross-sea bridge, and the first time to set the cable expansion joint device according to the bridge expansion joint. The construction of the project faced various difficulties and challenges from the very beginning.

The Meishan Island Bridge is flanked by fast lanes on both sides, and the cable laying space in the middle of the bridge is very narrow, and each cable telescopic device weighing 5 tons faces the dilemma of not being in place after arriving at the construction site. "Brothers, disassemble it first, transport it below and assemble it again." Ye Yong, the captain of the cable team, exhaled his arms, and more than 20 pairs of hands immediately disassembled one cable telescopic device after another into parts that were easy to lift and move.

Cranes, shoulders, a few trips, in this season that is still a little cool, everyone has already sweated like rain. After the parts were transported to the designated location, in order not to affect the construction behind, the construction team members "catted" in a narrow space for 5 consecutive days, carefully assembling all five telescopic devices like building blocks.

Equipment problems were solved, and new difficulties followed. On April 12, in the hunting sea breeze of the Meishan Island Bridge, the cable straightening machine had just stopped, and Ye Wei and several construction workers once again rolled out the construction plan to discuss. According to previous work experience, the difference in the relative position of the cable straightening machine can be used to achieve the bending of the cable, but after the on-site trial, it was found that the straightening machine was bulky and slow, and it could only be constructed 100 meters per day, and the cable that needed to be serpentine laid on the bridge was 6,000 meters, and it took 60 days to complete, and the whole project must be put into production in June, what to do?

"We must find a way to complete this cable laying in the shortest possible time." In the fierce sea breeze, everyone heard Ye Yong's firm voice. More than ten hours, six solutions, dozens of tests, and finally the construction scheme using the hand wrench hoist as a cable orthopedic tool was approved.

"One, two, three, up!" 10 pairs of green tendon hands tightened the hand wrench hoist along the cable path while prying the 9-ton cable with all their strength. Six silver "giant snakes" gradually surfaced, and the simple and efficient construction also reduced the construction period to 10 days.

"In just a few years, Meishan Island has been built from a barren and barren salt brine land to a new "giant ship" on the southeast coast, and the key is to rely on strong power support. "Beilun District Deputy District.