Two UHVDC lines simultaneously span 500 kV lines of the same gear

At 15:26 on April 7, the construction of two UHVDC lines in Ximeng-Taizhou and Zarut-Qingzhou simultaneously spanning 500 kV Huangbin Line I and Line II was successfully completed, which is the first time in China that two UHV DC lines simultaneously cross the 500 kV line in the same gear
.

The ±800 kV Ximeng-Taizhou UHVDC transmission project under construction is one of the 12 key transmission channels of
the national air pollution prevention and control action plan.
The ± 800 kV Zarut-Qingzhou UHVDC line project is a major project to implement the central government's strategic deployment of comprehensively revitalizing the old industrial base in Northeast China, which is of great significance
for optimizing Shandong's energy structure and strengthening air pollution control.
The Lu 1 tender sections of these two lines are both undertaken by Shandong Power Transmission and Transformation Engineering Company, and are parallel in Wudi County in Binzhou City, Shandong Province, and cross the 500 kV Huangbin I Line I and II Line 169 to Tower 170 line
.

The 500 kV Huangbin Line I and II are the second "foreign power into Lu" channel completed and put into operation, and are an important connection line
between Shandong Power Grid and North China Power Grid.
The crossing construction can only be carried out
by taking advantage of the power outage maintenance of the 500 kV Huangbin Line.
The 500 kV Huangbin Line power outage maintenance time is only 8 days, and the time to complete the crossing construction of two UHVDC lines is very tight
.
Therefore, the construction project department decided to carry out the construction of two DC lines at the same time
.
Since the distance between the 500 kV line being crossed is only 428 meters, and the distance between the left pole of the Ximeng-Taizhou line and the right pole of the Zarut-Qingzhou line is only 50 meters, the narrow construction space brings great challenges
to the construction project department.

In order to ensure the smooth construction of this construction, Shandong Power Transmission and Transformation Engineering Company made full use of the advantages of the two UHVDC lines built by them, planned ahead, prepared carefully, analyzed and demonstrated the construction plan, personnel organization, equipment and tools, safety guarantee, schedule plan, etc.
, and finally determined the overall organizational plan of "one management team, two independent construction groups" to ensure that the two lines spanned the construction in a coordinated manner
.
The construction project department mobilized more than 220 construction personnel from 9 teams to focus on tackling tough problems
.
The two DC lines are equipped with traction field and tension field respectively, which are highly coordinated during the construction process without affecting
each other.
The construction team prepared to enter the site 7 days in advance, and completed the primary and secondary guide ropes in other gears of the pay-off section before the power outage of the 500 kV Huangbin Line, so as to reduce the possible factors that may delay construction
during the power outage.

The two lines of Ximeng-Taizhou and Zarut-Qingzhou use eight-split conductors, and the largest cross-section conductor of domestic transmission lines is 1250 square millimeters
.
The construction project department adopts intelligent centralized tension pay-off equipment to carry out the synchronous unfolding construction of 4-× (one pull-two) conductors
.
The equipment is independently developed by Shandong Power Transmission and Transformation Engineering Company, and is specially developed by Shandong Power Transmission and Transformation Engineering Company for large-section conductor display, reaching the domestic advanced level
.
With the help of this equipment, 4 tension machines can be operated remotely by only one person in the multi-function command room, and the degree of construction automation is significantly improved
.
The synchronization level of the four tension machines is significantly better than the previous level of one-person control per tension machine, which played an important supporting role
in the successful completion of this construction.