Interconnected High-Voltage Pulsed-Power Converters System Design for H− Ion Sources

This paper presents the design and experimental validations of a system of three new high-voltage (HV) pulsed-power converters for the H sources. The system requires three pulsed voltages (50, 40, and 25 kV to ground) at 2-Hz repetition rate, for 700 μs of usable flat-top. The solution presents ripple-free output voltages and minimal stored energy to protect the ion source from the consequences of arc events. Experimental results on the final full-scale prototype are presented. In case of short-circuit events, the maximal energy delivered to the source is in the Joule range. HV flat-top stability of 1% is experimentally achieved with a simple Proportional-Integral-Derivative regulation and preliminary tuned H source (e.g., radio frequency control, gas injection, and so forth). The system is running since more than a year with no power converter failures and damage to the source.