hta presentation

1
RESONANT GROUNDING versus LOW IMPEDANCE
GROUNDING
2
Neutral Point TreatmentApplication Survey
Neutral point treatment in Germany

• Resonant grounding is also applied in
• Scandinavia
• numerous Central European countries
• Eastern Europe

VDEW Störungsstatistik 1998
3
Resonant GroundingBasics - Theory
E
Ires / IC
d
undercompensation
overcompensation
4
EPSY - Earth fault Protection SYstemSystem
Components
Earth Fault Compensation Controller
Earth Fault Detection
Arc Suppression Coil(ASC)
5
Resonant GroundingComparison
100 Earthfaults
Resonant grounding

• 70 ... 80 transient faults

• self-extinction by the ASC
• no influence on power supply

Low impedance grounding

• 20 ... 30 steady faults

• low fault current
• - increased human safety
• - reduced damage
• - reduced interference
• - reduced earthing effort

• - high fault current (e.g. 2 kA)
• - immediate tripping

high number of power interruptions
quality of power supply increased