This book addresses the fundamentals for determining short-circuit currents. Calculating these currents is one of the essential tasks in planning electrical networks. Since the networks must be operated reliably and safely, the calculations are standardized by international and national norms. The current IEC/VDE standard applies concrete calculation methods that have proven themselves over many decades. New technical developments are continuously incorporated. However, the backgrounds are often no longer known, which is why this book describes these fundamentals. The author has been involved in the standardization of short-circuit current calculation since 1972 and has compiled the insights gained during this time.
Introduction.- Standards for Short-circuit Current
Calculation.- Requirements and Calculation Methods.- Calculation Variables
for Equipment.- Calculation of the Short-circuit Currents.- Double
Line-to-earth Short Circuit.- Calculation of the Voltage Factor c.-
Correction Factors for Power Station Units and Power Transformers.- Component
Systems.- Breaking Current in Meshed Networks.- Calculation of the Thermal
Equivalent Short-circuit Current.- Contribution of Asynchronous Motors to the
Short-circuit Current.- Short-circuit Current Calculation with Converter
Systems.- Influence of Capacitors or Capacitive Compensation Units on the
Short-circuit Current.- Calculation and Operation with Parallel
Transformers.- Representation of Autotransformers in Short-circuit Current
Calculations.- Voltage Flashover Between Three-phase Systems with Different
Nominal Voltages.
Gerd Balzer was a full professor at TU Darmstadt in the field of Electrical Power System and was significantly involved for decades in national (DKE) and international (IEC) standardization in the area of short-circuit current calculation.
