Potentiality and effects of the 1 kV low voltage distribution system

Electricity distribution companies throughout Europe are facing same basic problems. The demand of better power quality is increasing and in the same time distribution networks are ageing and should be replaced. Due to the regulated nature of electricity distribution business there is also a demand from electricity market authorities for good quality of the distribution as well as high economical efficiency. It is clear that network investments are needed to match the growing demands of better quality distribution. The focus of this paper deals with studies in which alternative network solutions are evaluated. Especially is focused to comparison of three-voltage-level 20/1/0.4 kV distribution system to the traditional 20/0.4 kV solution. The theoretical network designs and practical experiences have shown that the 20/1/0.4 kV system is an economical solution compared to the traditional system when it enables replacing 20 kV medium voltage lines with 1 kV low voltage lines