Measuring of real value of short-circuit power in island operation condition

This paper deals with the problematic of the actual short-circuit power determination in real conditions. Presented principle of a real value of short-circuit power determination in arbitrary node of the power system is based on the measurement of one cycle RMS voltage and current changes. Described should be useful for determination of short-circuit power in the nodes electrically far enough from any synchronous machines (mainly from a generators of big power plants), in which the subtransient and transient effects of synchronous machines can be neglected. The comparison of the maximum short-circuit power computed according to the IEC 60909-0 standard and the actual short-circuit power obtained from the measurement of RMS voltage and current changes in the island operation of a small network is presented in this paper.