Senior Power Electronics Engineer

About Commonwealth Fusion Systems:  Commonwealth Fusion Systems is on a mission to deliver the urgent transition to fusion energy. Combining decades of research, top talent, and new technologies, we’re designing and building commercially viable fusion power plants. And we're working with policymakers, suppliers, and many others to build the energy industry of the future. We’re in the best position to make it happen. Since 2018, we’ve raised $4 billion of capital, making us the largest and leading fusion company in the world. Now we’re looking for more thinkers, doers, builders, and makers to join us. People who’ll bring new perspectives, solve tough problems, and thrive as part of a team. If that’s you and this role fits, we want to hear from you.
Join the power movement as a Senior Power Electronics Engineer 

Join the Pulsed Electrical Distribution System (PEDS) team at CFS as we begin development on the next-generation power supplies that will power ARC, the first grid-scale commercial fusion power plant. In 2027 our power supplies will supply SPARC with over 1GW of pulsed power. Develop a fusion engineering skillset and learn from SPARC as we demonstrate Q>1. Apply your power electronic experience to develop and qualify next-generation power supplies for ARC and beyond. We need a skilled power electronic engineer to lead our team.

What you'll do:

Architect and design the next generation of high power (>10MVA) medium voltage power supplies for ARC tokamaks utilizing latest Si and SiC semiconductor devices

Collaborate with power semiconductor device manufacturers to develop and qualify new devices for fusion focused applications

Model and simulate power electronic circuits and components to evaluate and characterize converter performance, efficiency, stability, etc.

Build, test, and validate prototype 4Q power modules (H-bridge, DC link, passives, thermal management, etc.) for use within ARC tokamak power supplies

Turn qualified prototype designs into productized solutions for ARC power supplies

Develop technical requirements, specifications and qualification plans for corresponding power circuit components (capacitors, magnetics, passives, etc.)

Support cross-functional team technical developments such as power distribution, energy storage, RF and other systems delivering electrical power for fusion applications

Document designs, simulations and test results into engineering reports

What we’re looking for:

8+ years of related experience with Bachelor’s degree (or) a Master’s degree with 6+ years of experience with power electronics based systems

Hands on product development experience for power electronic converter systems

Knowledge of various inverter circuit topologies and the benefits and limitations

Experience with modeling & simulation with analysis tools such as PLECS, PSPICE, MATLAB etc.

Extensive experience with semiconductor devices (IGBT, MOSFET, etc.) and magnetic components (transformers, inductors etc.)

Fundamental understanding of gate drive circuits, design and device protection

Experience with packaging design of power conversion equipment and thermal management

Experience with high power electrical equipment >10MVA

Experience with hands on testing of electrical components, sub-assemblies and systems in the laboratory and use of oscilloscopes and other measurement equipment

Excellent written and verbal communication skills, ability to conduct design reviews, organize and present results to both expert and non-technical audiences

Bonus points for:

Master’s degree in electrical engineering with a focus on Power Electronics

Experience with application of compliance standards to the designs (IEC, UL, CSA, NEC etc.)

Experience in problem solving, root cause analysis and field containment actions

Experience with hands on prototype build, prototype testing and documentation of results is a plus

Intelligent gate drive circuit design is a bonus

Must-have Requirements:

Ability to lift up to 50lbs

Perform activities such as standing, typing or sitting for extended periods of time

Willingness to travel or work required nights/weekends/on-call occasionally

Work in a facility that contains industrial hazards including heat, cold, noise, fumes, strong magnets, lead (Pb), high voltage, high current, pressure systems, and cryogenics

#LI-Onsite
At CFS, we excel in fast-paced environments, driven by our values of integrity, execution, impact, and self-critique. As we grow, we’re eager to bring on mission-driven folks who offer diverse perspectives and fresh ways to tackle challenges. We value diversity deeply and are proud to be an equal opportunity employer by choice. We consider all qualified applicants equally, regardless of race, color, national origin, ancestry, citizenship status, protected veteran status, religion, physical or mental disability, marital status, sex, sexual orientation, gender identity or expression, age, or any other basis protected by law. This role requires compliance with U.S. laws concerning the export of controlled or protected technologies or information (collectively, “Export Control Laws"). Any offer of employment will be contingent on the need for compliance with such Export Control Laws.