2008-05-15 - ABB has delivered the world’s first truly mobile high voltage substation. Designed for rapid and easy transport by road, sea or air, the MX1 is a compact, lightweight 170 kilovolt (kV) substation that can fit into an Antonov airplane for deployment anywhere in the world.
By Editorial services
The MX1 substation in action at a Vattenfall substation in Sweden, with the 52/24-12 kV mobile substation in the foreground. ABB designed the substation on behalf of Vattenfall, Europe’s fourth largest electric utility, in collaboration with transmission system operator, Svenska Kraftnät, to fill a need for a mobile substation that could be rapidly deployed by road, boat or plane in critical and emergency situations.
“It’s a complete 170 kV substation, engineered for emergency deployment and to restore power supply as quickly and effectively as possible,” says Vattenfall project manager Lennart Ahnlund.
Vattenfall is the largest grid operator in Sweden, with some 900,000 customers around the country.
Like many electric utilities in Europe today, the company is subject to fines and penalties for every hour that it fails to provide power to its customers.
For Vattenfall, it was crucial to be able to move the equipment by air using Antonov transport, the world's largest cargo aircraft. The substation covers a wide range of ratings (170/52/24-12 kV) and consists of several containers and one trailer.
Most impressively, it meets a number of demanding design specifications that make it uniquely flexible and mobile.
“Chief among these was ensuring that the solution would work flawlessly in all conceivable situations, despite the engineering complexity that a mobile substation always entails,” says Inge Johansson, chief designer of the MX1.
Among the significant design features of the MX1 are the following:
It must “work flawlessly in all conceivable situations, despite the engineering complexity that a mobile substation always entails.”
- Inge Johansson, chief designer
- Compliance with European freight regulations for width (less than 3.1 meters), height (less than 4 meters) and weight (less than 100 metric tons), which means that the MX1 can be transported by road without special permits or a police escort
- Components and containers were redesigned to reduce the size and weight of the solution so that it would fit inside an Antonov airplane – the world’s largest aircraft – for transport to disaster areas anywhere in the world
- The 25 MVA transformer is arguably the most compact and lightweight of its kind. It weighs only 57 tons (78 tons including the trailer and other equipment), which enables it to be transported by air
- Operation can take place in extreme temperatures as low as -50°C. This required an innovation in materials technology to make the 170 kV cable connections sufficiently flexible to withstand extreme cold.
Plug and play installation
The modular design of the MX1 means that it has the flexibility to operate as either a complete substation or as a replacement for disabled components.
The MX1 mobile substation is designed for rapid deployment and fast installation, so that power delivery can resume within hours. The modules consist of a trailer containing a 25 MVA transformer; a 170 kV container with gas-insulated switchgear; a 52 kV container with gas-insulated switchgear and three outgoing feeders; a 24 -12 kV container with air-insulated switchgear, gas-insulated breakers and five outgoing feeders; two containers with neutral-point equipment; one container with control and protection equipment, and one support container. Each component is pre-engineered for plug and play installation.
Vattenfall has one MX1 substation based in a strategic location to cover the northern half of Sweden, and is considering ordering a second MX1 for the southern half of the country. It has also deployed a smaller (52/24-12 kV) mobile substation, also designed by ABB, and has a further two under order.
ABB is the world’s leading provider of substation solutions. Mobile substations are particularly effective in growing economies where the power grid is weak and liable to disruptions.