Using 1kV low voltage distribution for connection of plug-in vehicles

Using 1kV as an intermediate voltage within the electric distribution system can be a cost efficient method for reinforcing the low voltage network when loads increase due to plug-in vehicles. This paper presents cost comparisons between different network reinforcement methods including different system typologies for the 1kV system. An estimation of network reinforcements needed in Sweden for domestic houses have also been conducted. Further on, different types of transformers for the 1kV system are descried. The 1kV system is especially suitable when the voltage on existing cable can be raised from 0.4kV to 1kV. This is possible for most modern low voltage cables. Examples of applications of 1kV systems are connection of car parks with charging equipment for plug-in vehicles and rural houses with a low short circuit power.