Short-circuit current estimation from measurements of voltage and current during disturbances

Short-circuit current is usually calculated theoretically using network parameters and network configuration. This paper describes a method for estimating the short-circuit current using measurements taken at the distribution feeders. The method makes use of small as well as large disturbances. As an example, the paper includes a statistical analysis of the short-circuit current estimates from disturbance measurements in a 20 hour period near a saw-mill. The short-circuit current value plays an important role in the evaluation of the severity of power quality degradation at the distribution voltage levels