Problems Encountered in the Introduction of Low-Resistance Neutral Grounding in the 100-kV Urban Network in Dresden.

Additional problems that have arisen in the introduction of low-resistance neutral grounding as a result of the coupling of zero systems both with the 220-kV network and the middle-voltage network are considered. Whereas no impermissible stresses can be shown in the zero system coupling in the 220-kV network, the ground fault in the low-resistance neutral grounding of the 110-kV network causes impermissible voltages of the resonance grounded middle voltage network. Transformer zero impedances, ground propagation resistances, and the installation points of grounding fault chokes are considered.