Ion current droop compensation

A pulse generator comprising:

• a DC source;
• a transformer comprising:
• a transformer core;
• a primary winding wrapped around at least a portion of the transformer core, the primary winding having a first lead and a second lead;
• and
• a secondary winding wrapped around at least a portion of the transformer core;
• a droop compensation circuit electrically coupled with first lead of the primary winding;
• a first switch electrically connected with the droop compensation circuit and the DC source;
• a second switch electrically connected with the second lead of the primary winding and the DC source, wherein the first switch and the second switch are opened and closed at different time intervals;
• and
• a pulsing output electrically coupled with the secondary winding of the transformer that outputs high voltage bipolar pulses having a peak-to-peak voltage greater than 1 kV and a voltage portion between consecutive high voltage bipolar pulses that has a negative slope.