Solid-State Nanosecond HV Pulse Generator
Pulse generators for kicker systems in synchrotron light sources must deliver pulses in the nanosecond range with rise and fall times in the sub-nanosecond domain. Due to the strict timing requirements, a special opening switch is employed.
Solid-state high-voltage pulse generators capable of producing short pulses with fast-rising and falling edges are essential for a wide range of technologies and applications. One example is the processing of CO2 using cold plasma to dissociate the molecules. Furthermore, the injection and extraction systems of particle accelerator facilities require short, fast rising/falling, and highly precise high-voltage pulses.
The primary target application for this project is the development of pulse generators for the kicker systems of synchrotron light sources such as the SLS 2.0 at PSI and the PETRA IV at DESY. These kicker systems are essential for the injection and extraction of electron bunches into or from the main particle beam. With the ongoing upgrades to these facilities, the pulses that drive the kickers are subject to particularly demanding timing specifications, with pulse widths in the nanosecond range and rise and fall times in the sub-nanosecond domain.
In general, these requirements are impossible to achieve with ordinary semiconductor switches like IGBTs, MOSFETs, and even GaN HEMTs. Even the modern wide-bandgap semiconductor variants of these devices are not fast enough. Consequently, the approach for this project is the development of pulse generators based on specially designed ultra-fast opening switches that interrupt currents through inductive energy storages.
To achieve this goal, the project funded by external page CHART is structured around two main pillars. The first pillar is the design, fabrication, and optimisation of such opening switches capable of achieving the required switching speed and pulse energy. In addition to the opening switch itself, the pulse generator requires a dedicated driving circuit that enables the switch to interrupt the current through the inductive energy storage and subsequently deliver the pulse to the load. Analysing and minimising parasitic elements within this circuit, as well as ensuring proper impedance matching along the pulse propagation path, are essential for optimal performance. Therefore, the design and optimisation of this driving circuit constitute the second pillar of the project.