SBIR/STTR Award attributes
The requirements on the driving pulse for Electron-Ion Collider (EIC) kickers include extremely high peak voltage of +/-50 kV (dual-channel) to be dissipated in a 50 Ohm kicker impedance, which brings operation peak current level to ~ 1kA. Existing drivers (pulsers) are operating at only a few kilovolts, and most of them utilize HV MOSFET switches, using single switch per each channel. However, one problem with MOSFET transistors is due to their residual resistance (on the order of several tens of Ohms), which dramatically limits their efficiency. Thus, a state-of-the-art MOSFET approach is not applicable for the EIC kickers system due to low efficiency, instability, high voltage requirements, and other solutions are sought. In response to this problem, RadiaBeam Technologies proposes to develop and test a high output pulse generator based on distributed pulser topology that will utilize novel GaN transistors as switching devices. GaN is a rapidly growing transistor platform, which enables both high peak and average power operations along with extremely short switching times of nanosecond-scale, well within very tight margins on the rise and fall times of EIC kickers. In Phase I, we will perform a thorough pulser topology optimization, resulting in an optimal combination of parallel switching sub-elements – we will find the right balance between a number of sub-elements and their individual power levels, in the context of the system performance, complexity, footprint, heat management, and power combining scheme. We will also assemble and test the switch to validate the proof-of-principle and show the scalability to 50 kV in the developed system topology. Phase I development efforts will be a starting point for actual fabrication, assembly, and high-power testing of the complete pulser system in Phase II. In addition to primary user of the system proposed herein (EIC at Brookhaven National Lab), the variants of the developed high voltage nanosecond pulser may find various applications involving HV switches or high frequency power in national laboratories, including fast beam choppers, next generation light sources using energy recovery linacs (ERLs), ion clearing gaps for ion beams, and FET-driven replacement of radio frequency quadrupole (RFQ) accelerating structures. Other important applications of high voltage pulsers include: high power laser technology (i.e. to drive Pockels cells), manipulation and control of non-equilibrium plasmas, as well as for EMC/HIRF testing of critical equipment and processes.