Senior Power Electronics Engineer

Commonwealth Fusion Systems LLC; Harvard (MA); On-site; USD 134,000 - 205,000; Full time

Benefits offered by this job

Equity

Holidays

Flexible vacation

Sick days

Parental leave

Health insurance

Dental insurance

Vision insurance

401(k) matching

Career growth

Team events

Job summary

Commonwealth Fusion Systems LLC is seeking a Senior Power Electronics Engineer to lead the design of next-generation high-power power supplies for ARC tokamaks. You will drive architecture, simulations, testing, and qualification with a focus on efficiency and reliability.

You will collaborate across engineering teams, work on >10MVA systems, and contribute to the SPARC program’s 1 GW pulsed power roadmap. This on-site role offers equity and comprehensive benefits.

Qualifications

• 8+ years of related experience with a Bachelor's degree or 6+ years with a Master’s in power electronics
• Hands-on product development experience for power electronic converter systems
• Knowledge of inverter circuit topologies and their trade-offs
• Experience with modeling and simulation tools such as PLECS, PSPICE, MATLAB
• Experience with semiconductor devices and magnetic components
• Understanding of gate drive circuits and device protection
• Experience with packaging design and thermal management
• Experience with high power equipment >10MVA
• Experience with hands-on testing and measurement equipment
• Strong written and verbal communication skills

Responsibilities

• Architect and design high-power (>10MVA) medium-voltage power supplies for ARC tokamaks
• Collaborate with semiconductor manufacturers to qualify new devices
• Model and simulate power circuits to evaluate performance
• Build and test prototype 4Q power modules
• Translate prototypes into productized ARC power supplies
• Define technical requirements and qualification plans for components
• Support cross-functional teams delivering fusion power systems
• Document designs and test results in engineering reports

Skills

Power electronics

Inverter topologies

Modeling & simulation

IGBT/MOSFET devices

Thermal management

Prototype testing

Technical communication

Cross-functional collaboration

Education

Bachelor's degree in Electrical Engineering

Master's degree in Electrical Engineering (preferred)

Tools

PLECS

PSPICE

MATLAB

Job description

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

$134,000 - $205,000 a year

Salary range for this full-time position + equity + benefits. The actual salary will depend on level, location, qualifications, and experience. The range displayed on each job posting reflects new hire salaries for the position across all US locations.

Benefits include:

• Competitive compensation with equity
• 13 Company-wide Holidays
• Flexible vacation days
• 10 sick days
• Generous parental leave policy
• Health, dental, and vision insurance
• 401(k) with employer matching
• Professional growth opportunities
• Team-building activities

#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.