Lead Power Electronics Engineer – High-Power Inverter Systems

Sapphire Technologies, Inc.•Cypress, CA

3d•Onsite

About The Position

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.

Requirements

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 tradeoffs 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.

Nice To Haves

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

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.