DC Power Systems and Protection Engineer

About Fluidstack

We exist to make humanity more free. For most of human history, you farmed or you starved. Technology gave people more time for the things they wanted to do, instead of things they had to do. Powerful AI will be the biggest lever for human choice we've ever built - but only if models are aligned with what humanity actually wants. There are groups building AI who don't share these goals. Whoever deploys frontier compute infrastructure fastest will decide whether AI expands human freedom or shrinks it.

We're singularly focused on delivering 10 to 100s of GWs of compute faster than anyone else, rethinking every layer of the stack. We acquire power, design and build data centers, and operate them - with teams spanning hardware and software. Speed and scale are our key differentiators. Come be a part of building civilization-scale infrastructure for AI.

We hire people who care deeply about this problem space. If that is you, please apply!

How We Operate

• Be a barrel. Full autonomy. Own things end to end, take on scope without being asked, no permission required to operate outside your core role.

• Insane urgency. We drive everything forward as fast as possible.

• Reason from first principles. Challenge every assumption. Zero analogy thinking, no egos, the best idea wins.

• Love of the game. The frontier of AI is the most interesting problem of our time. We put in long hours at high intensity to push the frontier forward.

• Build something that actually matters. If you're going to spend your time, spend it on something that matters to the world.

The Product Engineering Team

Product Engineering builds the power and cooling systems that let Fluidstack deliver gigawatt-scale AI data centers faster and denser than the grid-standard supply chain allows. The SST group is designing solid-state transformers as a core building block of that power architecture.

Examples of key problems the team is working on

• Architect a medium-voltage solid-state transformer that can be manufactured, serviced, and scaled across gigawatt-scale campuses, not just demonstrated in a lab.

• Define the interface between the SST and the MVDC distribution system, including protection, control boundaries, and fault behavior.

• Build a semiconductor and magnetics supply strategy that survives a thin 10kV SiC market over a multi-year horizon.

• Take converter hardware from topology selection through working prototypes on a schedule that data center construction actually depends on.

Role Scope

• Own protection and grounding for every zone, from a bipolar medium-voltage DC bus carrying hundreds of megawatts over miles to the 1,500 V solar and battery bus and the 800 V racks.

• Specify, and where no product exists co-develop with vendors, the DC breakers, fuses, and disconnects for these buses, from medium-voltage feeders to hall buses carrying tens of thousands of amps.

• Design fault clearing without conventional breakers where possible, using SSTs that stop switching within microseconds, isolators that open at zero current, and fuses only where paralleled units can backfeed, and prove it in electromagnetic transient studies.

• Turn fault studies into requirements every SST, battery converter, and breaker vendor must meet: fault current contribution, interruption time, and coordination settings.

• Run live short-circuit and interruption tests on an energized multi-SST bus that prove the design to insurers, lenders, and the authority having jurisdiction.

What We're Looking For

The below is a starting point. We always make space for exceptional people, so if you don't fit this role exactly, tell us where you would.

• You've designed protection for a medium- or high-voltage DC system (MVDC, HVDC, shipboard, rail, or DC microgrid) and seen it through commissioning.

• You've built and run electromagnetic transient models of converter-dominated systems, and used them to set breaker, fuse, or relay requirements.

• You've made a grounding call (solid, resistance, or floating) and defended its trade-off between fault current and insulation stress.

• You've specified, designed, or qualified DC breakers, fuses, or switchgear for medium-voltage or high-current DC, and tested them through interruption.

• You've written protection requirements a converter or breaker vendor had to redesign to meet.

• You find the failure case others missed and can show it in a single simulation plot.

• Bonus: DC interruption technology (solid-state and hybrid breakers, high-speed DC fuses). EMT simulation (PSCAD/EMTDC, EMTP, PLECS, MATLAB/Simulink). Protection coordination and relay settings (ANSI device functions, IEC 61850). MVDC standards (IEEE 1709). Professional Engineer license (PE).

We are committed to pay equity and transparency.

Fluidstack is an Equal Employment Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, sexual orientation, gender identity, disability and protected veterans’ status, or any other characteristic protected by law. Fluidstack will consider for employment qualified applicants with arrest and conviction records pursuant to applicable law.

You will receive a confirmation email once your application has successfully been accepted. If there is an error with your submission and you did not receive a confirmation email, please email View email address on jobs.ashbyhq.com with your resume/CV, the role you've applied for, and the date you submitted your application-- someone from our recruiting team will be in touch.