Application and evaluation of a new concept for compact series compensation for distribution networks

A newly developed distribution series power capacitor concept has been field tested in a joint project between Gullspangs Kraft AB and ABB Power Systems AB. Due to growing load, a voltage profile problem was experienced in a 12 kV radial distribution system in a rural area. Series compensation was found to be a suitable and cost efficient way to improve the voltage and the loadability of the system. The series capacitor has performed successfully in service since commissioning in November 1990. The paper describes the actual network and the evaluation of different possibilities to improve the voltage and the loadability of the system. Estimation of differences in investment costs are shown. It further gives a description of the series capacitor equipment and its basic performance. The paper finally reports on general experience gained during the field test period, especially with regard to the particular line fault statistics