Customized plug-and-play mobile power supply from a container
In connection with the expansion of Copenhagen's Metro M4 line Hans Følsgaard A/S has delivered two containers with switch gear and transformers for electric power. The concept is an affordable power solution, allowing the electric power to be moved to wherever the project requires a 10kV level
No building and construction site without electric power. Everyone involved in construction knows this, and in most cases, power solutions are designed as mobile switchboards that have a series of CEE sockets that typically supply lights, crew rooms, power tools and other temporary installations on the construction site. But it happens from time to time that the requirements for temporary energy supply of building and construction tasks require higher voltages and currents than the usual switchboard solutions can provide - without the requirement for mobility being compromised.
For Hans Følsgaard A/S, this has led to a task for the joint venture company Tunn3l JV, which is responsible for the main contract for the expansion of the M4 metro line with five new stations. The metro construction requires, in addition to the usual supplies for lighting, ventilation, crew rooms and tools also power supplies for the tunnel boring machines that carry out the excavation work.
The solution resulted in two 20-foot containers that contain switch gear and transformers, respectively. The containers constitute mobile solutions, which contain two fields that supply the tunnel boring machines at the 10kV level and two fields that supply power via the transformers at a 10/04kV level. Switch gear and transformers have been sourced by Hans Følsgaard A/S from their supplier, Ulusoy Elektrik. It is a Turkish manufacturer that is characterized by a large production of equipment at the medium voltage level, and which is also quite suitable for the conditions under which Tunn3l JV is working.
Since 1985, Ulusoy Elektrik has supplied products with the best price/quality match. Do not underestimate Turkey as an industrial nation. The Turks manufacture a lot of products as subcontractors to, among others, European OEM companies, just as Turkey today has several well-known brands. Ulusoy Elektrik's components for the medium voltage range can work for decades under normal operating conditions. Still, the price is so low, that the depreciation time is short when used in temporary functions such as construction power solutions, where the treatment can be a bit harsh during relocation, says Kristian Førby Pedersen, product manager for Powertech in Hans Følsgaard A/S.
A delivery from your Technical Partner Hans Følsgaard
Our goal is to supply our customers with as complete solutions as possible, who thus have turnkey and fully functional products that are ready to use - as is the case for the containers. Tunn3l JV has manufactured the feet on which the containers stand, but otherwise Følsgaard has manufactured the containers in collaboration with the company's suppliers and local partners.
- Containers are generally built on a bottom frame that is very stable and solid than the corrugated metal sheets that sides and top are made of. We have mounted the switch gear and the transformers on the frames, allowing the containers to be moved from one position to another without working the products inside the container loose. We have performed the final function test with high voltage in our company, thus Tunn3l JV has received a product that is ready to use, Kristian Førby Pedersen explains.
The delivery includes voltage setting and the cables that connect the two containers and thus the transformers to the switch gear. The construction is based on Radius being able to introduce a 10kV cable to the container with the switch gear, where an electricity meter is also installed, so that the energy is settled at a 10kV level. The solution can deliver a maximum of 630A at 10kV level.
Ready for use in 2024
Copenhagen Metro is in the process of building five metro stations in Sydhavnen, as an extension of the City Ring, which has just been taken into use. The stations will be an extension of the metro line M4, which goes to Nordhavn station. This will give a very short transport time between Nordhavnen and Sydhavnen, and the stretch is in round figures three kilometers long.
When the metro stations in Sydhavn open in 2024, the southern part of Copenhagen will thus be connected to the metro network, and an even stronger public transport network will be created, which will reduce congestion and increase mobility in the capital area. The new stations will then be Havneholmen, Enghave Brygge, Sluseholmen, Mozarts Plads and Ny Ellebjerg.
- The tunnel boring machines are supplied with 10kV, which drives the drill head and propulsion. From the power supply containers, a cable is led down into the excavation, where the supply is terminated in an electrical cabinet. The tunnel boring machine itself has a 300 meter long flexible cable, which is connected to the electrical cabinet in the tunnel, and the fixed connection is continuously extended so that the fixed cable in the tunnel is extended in step with the progress in the drilling, says Kristian Førby Pedersen.
There are always a few unknowns associated with major construction work, and therefore the container model for the construction power supply is a really good idea. If there is a need to change the configuration during the construction work, then it is a fairly simple process, which quite frankly only requires a container truck with a crane.