Читать книгу Practical Power Plant Engineering - Zark Bedalov - Страница 75

The HV and EHV equipment at this voltage level is expensive. The transformer γ/Δ winding configuration with solid (effective) grounding with no resistance on the primary winding allows the manufacturers to apply lower BIL levels for the HV windings and to lower the cost of transformers and other equipment. The line tower footing ground resistance must also be kept low to reduce the BIL level of the line, thus cutting the cost of towers while offering the use of lower clearances and shorter insulator strings.