Patent ID: 6948305

Claim:
An apparatus for driving a plurality of ion thrusters including at least a first ion thruster and a second ion thruster, comprising: at least one voltage-regulated power supply, each voltage-regulated power supply for driving a common element in each of the plurality of ion thrusters, the common element in each of the plurality of ion thrusters being coupled together at a common point; a current sensor of a first neutralizer cathode of the first ion thruster providing a first sensed current; a second current sensor of a second neutralizer cathode of the second ion thruster providing a second sensed current; a control circuit for providing a current comparison between the first and second sensed currents; and a current balance circuit including a bias power supply coupled to the control circuit, the current balance circuit for providing a substantially balanced current to each neutralizer cathode of the plurality of ion thrusters, and the bias power supply providing a voltage difference to the first neutralizer cathode relative to the second neutralizer cathode based upon the current comparison relative to the common point.