Unit-iii Generation of High Voltages and High Currents

3. Explain the necessity for generating impulse currents and mention the features of impulse current generators. Impulse current generation is required for, o Testing of surge diverters o Testing of non-linear resistors o Electric arc studies o Studies of electric plasmas in high current discharges  For producing impulse currents of large value, a bank of capacitors connected in parallel are charged to a specified value and are discharged through a series R-L circuit.  Waveshapes used in testing surge diverters are 4/10 and 8/20 μ s. The tolerances allowed on these times are ± 10% only.  Rectangular waves of long duration are also used for testing. The rectangular waves generally have durations of the order of 0.5 to 5 ms, with rise and fall times of the waves being less than ±10% of their total duration.