Effects of the IEC publication 38 'IEC standard voltages' to the public low voltage networks

摘要

In IEC 38 a worldwide uniform low voltage value of 230/400 V is specified. The related voltage range poses increased requirements to the automatic tapping of the high-voltage/medium-voltage (HV/MV) feeding transformer. In this respect control criteria are investigated including the voltage dependency of the electric load. Furthermore it is necessary to develop a simple measurement procedure which may be used for recording voltage limit violations. This system should only record voltage values under normal operating conditions. The authors report on an adequate measurement system for recording the mean values averaged over a period length of ten minutes. In the case of a lower voltage limit violation despite an optimal control strategy of the MV value power system, reinforcement or other technical measures become necessary. Different possibilities are presented. In order to find the optionally suitable solution a strategic procedure may be helpful. A systematic discussion of these methods is given.