Capability 02
High-Voltage and Power Electronics
A plasma is not a resistor. It refuses to conduct until it suddenly does, and the electronics on the other side of that transition have to be built for both states.
- 01 Conditioning stage Takes bus power and shapes it into something a discharge can be started from, without disturbing the bus.
- 02 Ignition path Delivers the high voltage needed to break the gas down — then must get out of the way within microseconds.
- 03 Current regulation Once struck, the load is close to a short. The stage that survives that transition is the one that defines the design.
- 04 Protection and sensing Fault detection fast enough to act before the energy already in the converter reaches the electrodes.
The problem with a plasma load
Before breakdown, the gap between the electrodes is effectively an open circuit: the supply has to raise the voltage until the gas ionises. The instant it does, impedance collapses by orders of magnitude and the same supply has to become a current source before its stored energy destroys something.
That transition is where most plasma power stages are actually decided. Everything else — efficiency, mass, thermal design — is negotiable around it.
The load then stays awkward. Discharges wander, restrike and produce broadband electrical noise, in the same enclosure as the instrumentation meant to measure them.
What we take on
- High-voltage conditioning and ignition stages, including transformer design
- Current regulation through and after breakdown
- Fault detection and protection sized to the energy actually stored on the board
- Layout for high dV/dt: creepage, clearance, and returns that go where intended
- Conducted and radiated emissions, treated during design rather than after
- Thermal design and derating for the intended environment
Beyond propulsion
The same problem — deliver controlled energy into a load that changes state — appears well outside thrusters: surface treatment, plasma sources for materials work, ozone generation, and any industrial process where a discharge does the work. We take those on where the electrical problem is the hard part.
How an engagement runs
Usually from an electrical specification and a load that is only partly characterised. Where the load is not yet known, characterising it on a bench comes first — designing a converter for an assumed impedance curve is how a project loses six months.