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Lead Power Electronics Engineer – High-Power Inverter Systems

Sapphire Technologies
1 day ago
Full-time
On-site
Cypress, California, United States
$143,993 - $194,815 USD yearly
About Us:

Sapphire Technologies delivers power and cooling to energy infrastructure. Our FreeSpin® In-line Turboexpander recovers the energy wasted when high-pressure gas is stepped down, converting it into clean electricity and low-temperature cooling. To better serve our customers in the data center industry, we are now expanding our high-speed turbomachinery offerings into oil-free compressors for chilling applications. 

Our hands-on engineering team takes products from concept to field deployment, with work spanning rotating machinery, power electronics, controls, and systems integration.

We are a mission-driven organization with one common goal: building a more sustainable world. Our employees are our biggest asset, and we are looking for change agents to join us on our journey. 

Position Summary:
Sapphire Technologies is seeking a Lead Power Electronics Engineer to lead the architecture, development, validation, and production launch of advanced inverter systems for high-speed rotating machinery.

The role will support a major new product platform serving rapidly growing data-center infrastructure applications. The system integrates high-power electronics, high-speed electric machines, active magnetic bearings, liquid cooling, controls, and precision electromechanical hardware and is expected to undergo a significant production scale-up.

This is a hands-on technical leadership role with primary responsibility for inverter system architecture, power-stage design, cost reduction, design for manufacturing, thermal integration, validation, and certification readiness. The successful candidate will work closely with mechanical, controls, manufacturing, supply chain, certification, and Calnetix engineering teams. Hands-on laboratory and prototype-development work is required. Approximately10% travel may be required for suppliers, certification testing, customers, commissioning, or field support.

Key Responsibilities:
  • Serve as Sapphire’s primary technical authority for the inverter system.
  • Translate system and customer requirements into inverter architecture, technical specifications, and interface requirements.
  • Lead topology selection and trade studies involving:
  • Semiconductor technology and switching frequency
  • Switching and conduction losses
  • Harmonic performance and filter losses
  • Efficiency, power density, thermal margin, cost, and manufacturability
  • Lead the design and validation of power stages, gate drives, DC-link systems, filters, sensing, protection circuits, bus structures, and high-power interconnections.
  • Define and manage electrical, mechanical, and thermal interfaces, including water-cooled cold plates, coolant requirements, pressure-drop constraints, and component junction-temperature limits.
  • Develop electrical and thermal models to guide architecture decisions and verify design margin.
  • Lead schematic development, component selection, layout review, prototype build, laboratory testing, and design verification.
  • Drive cost reduction through architecture optimization, component standardization, supplier engagement, value engineering, and design for manufacturing and assembly.
  • Coordinate with Sapphire’s certification engineer and external certifying bodies to ensure compliance requirements are incorporated into the design early.
  • Support EMC/EMI, electrical safety, environmental, and applicable UL and IEC certification testing.
  • Define production-test requirements and support new-product introduction, supplier qualification, and manufacturing scale-up.
  • Support root-cause investigations for production and field issues.
  • Mentor engineers and manage technical work performed by contractors and external development partners.
  • Direct firmware development is not a primary responsibility of this position.

Base Pay Range: 

The information below is a general guideline. Actual compensation depends on the candidate’s experience and qualifications, as well as market and business factors.   

Salary range: $143,993 - $194,815



Requirements

Required Qualifications:
  • Bachelor’s or master’s degree in Electrical Engineering with emphasis in power electronics; doctorate is a plus.
  • Eight or more years of industry experience developing medium- or high-power inverters, motor drives, converters, or related industrial electronics.
  • Demonstrated experience defining power electronics architecture and leading products through design, validation, certification, and production.
  • Strong understanding of three-phase inverter systems, modulation methods, semiconductor switching behavior, protection, and power quality.
  • Experience evaluating trade-offs among switching frequency, semiconductor losses, passive-component size, filter losses, thermal performance, and cost.
  • Strong circuit-design and debugging skills across power stages, gate drives, sensing, protection, and high-voltage interfaces.
  • Experience with SiC-based inverter systems; GaN experience is beneficial.
  • Experience with liquid-cooled power electronics and thermal-interface design.
  • Proficiency with MATLAB/Simulink, PLECS, LTspice, or comparable simulation tools.
  • Hands-on experience with oscilloscopes, power analyzers, AC/DC sources and loads, and high-voltage current and voltage probes.
  • Ability to develop test plans, analyze results, document conclusions, and communicate recommendations to technical and management teams.
  • Strong technical leadership and cross-functional communication skills.
Preferred Qualifications:
  • High-power drives for high-speed permanent-magnet machines
  • Active-front-end or grid-connected converter systems
  • Output, input, and common-mode filter design
  • High-frequency magnetics design and optimization
  • Altium schematic capture and PCB-layout review
  • High-density packaging and low-inductance busbar design
  • Water-cooled cold plates and thermal-system integration
  • EMC/EMI testing and design for compliance
  • UL, IEC, CE, or related industrial product certification
  • Functional-safety and SIL-related product development
  • Production cost reduction, supplier development, and high-volume manufacturing
  • Turbomachinery, HVAC, refrigeration, energy, or data-center infrastructure applications
Work Environment: 
This role is primarily on-site and involves work in the office, manufacturing, equipment-insallation, and test environments. Appropriate personal protective equipment and adherence to site safety requirements are required. Some activities may require coordination outside normal operating hours. Travel to suppliers, manufacturing partners, or other company locations may be required. 

Benefits

Benefits:

We offer a competitive benefits package designed to support the health, well-being, and financial security of our employees. Eligible team members receive paid vacation, paid sick time, comprehensive health benefits, and participation in a 401(k) retirement plan with company match.

Additional Information:

The above job description is not intended to be an all-inclusive list of duties and standards of the position. Incumbents will follow other instructions and perform other related duties as assigned by their supervisor. Management reserves the right to change, rescind, add, or delete the duties and responsibilities of positions within this job classification at any time.

Sapphire Technologies is an equal opportunity employer and prohibits discrimination based on race, color, religion, national origin, gender, sexual orientation, gender identity, age, physical or mental disability, or veteran status. This policy applies to recruiting, hiring, transfers, promotions, terminations, compensation, and benefits.