Electron Gun Driver
In 2010, EHT developed a 10 kV, 1 kA electron gun driver. This power supply used twelve IGBT-based switches arranged in a series stack configuration and was capable of fast rise/fall times. A system schematic is shown in the figure. In addition to developing the series stack of IGBT switches, EHT developed a fiber-optically isolated charge/dump system to safely discharge the high voltage capacitors used in the system. Each stage of the IGBT supply included a fault alert LED that would turn off in the event a fault was detected. EHT engineers developed an interlock controller so that all in the event a fault is detected no gate drive signal would be transmitted to the IGBTs. The power supply has been used in a demanding plasma physics laboratory setting for over 18 months before the electron gun was decommissioned.