Main >>Applications >> Sample problems >> Charging of the metal sphere through the current limiting resistor
Simulate the charging process, determine the charging time, and calculate the maximum current.
Transient electric field
All dimensions are in mm
Relative permittivity of the air ε = 1;
Conductivity of metal g = 8 000 000 Sm;
Resistor R = 0.8 Ohm;
Nominal voltage E = 1.5 V.
This system can be represented by an equivalent circuit with voltage source E, resistor R and capacitor C connected in series. The ground potential is zero. Resistor R limits the charging current value. Resistor is modeled directly in the QuickField problem by the block "resistor".
First the current hits the maximum value of 3.5 A. Then the current decreases rapidly and at 3*10-10s. the process ends (99.9% of full charge).
Download simulation files metal_sphere_charging.zip