TEPCO has a wealth construction experience in underground power system. Many
other utilities (subways, communication cable and water pipes, and other objects)
run below the narrow roads in density-populated area, Tokyo. We have a lot
of achievements in design, construction technology regarding with power cable
tunnel, cable installation and cooling system. We can provide high level and
quality consultancy services on Master Plan, Feasibility Study and so on.
Subways, telecom cables, gas pipes, water pipes, and many other objects run
below the narrow roads, while heavy traffic causes frequent traffic jams .
With the large demand and limited amount of space, TEPCO has been in the business
of constructing underground transmission lines for decades. To meet this challenge,
we have developed various kinds of transmission line technology among them "Tunnel
Installation" and "Cooling System" .
1. Content
(1) Tunnel Installation
In the past, underground transmission lines were installed in pipes or directly
buried in the ground. However, these methods have become difficult as the number
of cable circuits and other underground facilities increases. Consequently,
TEPCO has been constructing tunnels, which enables us to install many circuits
in a limited area, mainly by shield method which can pass under other objects
and reduces influence on traffic.
(2) Cooling System
Heat is generated when electricity flows through cables. When many circuits
are installed in a small area, only a small transmission capacity can be
obtained due to the large amount of heat eliminating from the cables. However,
TEPCO has achieved large power transmission capacity in a limited area by
developing tunnel cooling systems. One system is an air-cooling system using
electric fans. Another system is the cooled water circulation system with
water pipes and refrigerators .
(3) Cable
Recently TEPCO uses XLPE cables which have less transmission loss, no oil
tanks, and easy maintenance characteristics. TEPCO has experience in XLPE
cable up to 500 kV
2. Scope
3. Example of Our Competence
| Title: |
Joint Study on “Technical Guideline for Underground
Transmission System Designing |
| Client: |
TNB Transmission Network Sdn Bhd |
| Term: |
January – July 2006 |
| Project Overview: |
In order to standardize and optimize the work underground transmission
system designing, established the “Technical Guideline for Underground
Transmission System Designing”, which states the design philosophy
and the functional requirements demanded for the equipment and installation. |
