We're looking for a Principal Power Electronics Engineer to set the technical direction for the grid-connected inverters at the heart of ON.energy's AI UPS product family. This is the senior technical voice for power electronics on the product team: you architect the converter and controls approach, resolve the hardest engineering trade-offs, set the engineering standards others work to, and represent ON.energy's inverter engineering externally - to vendors, customers, certifying bodies, and the broader industry. You are fluent in power electronics, its controls (grid-following and grid-forming), and BESS integration - ideally with UPS experience in mission-critical applications - and you own the inverter technical thread from proposal through FAT, commissioning, and field feedback for MW-scale systems. Key Responsibilities Architecture & technical authority • Own the grid-connected-inverter product architecture and converter-controls strategy - grid-following and grid-forming operation, current limiting, and dynamic grid support - and the technical roadmap across concurrent product cycles. • Define the engineering standards, design rules, and review gates the team works to; act as the final technical authority on the inverter change baseline. • Serve as the company's SME for grid-code and UPS performance compliance - IEEE 2800, IEEE 1547, UL 1741, IEC 62040-3, ERCOT ride-through - and set the inverter qualification / type-test program, acceptance criteria, and current-limit / short-circuit and data-evidence requirements suppliers must meet. • Act as the ultimate escalation point for inverter root-cause analysis (current-limit, post-fault recovery, thermal, control instability) and drive corrective design changes. • Mentor senior power-electronics, controls, and project engineers to scale the team's technical capability. Vendor management & supply strategy • Own the strategic inverter vendor / OEM relationships and decide their architecture - sole-source vs dual-source, co-development depth, and IP boundaries. • Set and enforce the inverter technical qualification process; run the highest-stakes design reviews and resolve the highest-stakes vendor escalations personally. • Oversee vendors through design, FAT, serial production, and post-deployment corrective action; own procurement technical specifications and acceptance. • Maintain vendor scorecards and drive continuous improvement across the supply base. Proposal, documentation & project support • Support business development with technical proposals - SLDs and GAs - that meet the customer's needs, and compile inverter technical information packages for the project engineering team. • Co-lead review and validation of inverter-related topics during project execution; maintain technical documentation, including as-built drawings. • Support integration of the inverter with the EMS, Plant Controller, and SCADA layers. Product development • Capture design-improvement feedback across the design, commissioning, and O&M phases and turn it into product changes. • Recommend design approaches and vendors for the main equipment; participate in product design sprints and in the product's commissioning phase. Required Qualifications & Skills • Bachelor's degree in Electrical Engineering, Power Electronics, or a closely related technical field; MS preferred. • 10+ years of hands-on power-electronics engineering, with a demonstrated record of operating with minimal direction in a senior technical role. • Architecture-level decision authority on previous grid-connected-inverter, power-electronics, or BESS equipment - you've made the trade-off calls others built around. • Proven system-level design of MW-scale power-electronics equipment, with deep converter-controls depth (grid-following / grid-forming, current limiting, protection). • Fluency producing and reviewing SLDs, GAs, schematics, and panel layouts; expert with AutoCAD or equivalent E-CAD. • Standards authority: UL 1741, IEEE 1547, IEEE 2800, IEC 62040-3, NFPA 855 / UL 9540 context; modeling with EMT tools (PSCAD, MATLAB / Simulink, PLECS). • Strong track record running strategic vendor / OEM relationships through design, FAT, serial production, and post-deployment escalation. • Excellent written and verbal communication - specs, technical positions, design-review leadership, and board-level briefings. • Willing to travel up to 25-30% for FAT inspections, site commissioning, customer engagements, and vendor reviews. Preferred Experience • Direct experience with data center / UPS / mission-critical power or utility-scale BESS at the architecture level. • Grid-forming inverters, advanced power-semiconductor (e.g., SiC) designs, and weak-grid / low-SCR EMT and impedance-stability validation. • History of leading products through NRTL certification (UL, CSA, Intertek) and FAT / commissioning. • Active Professional Engineer (PE) license; involvement in standards bodies (IEEE, UL, IEC, NFPA); patents or peer-reviewed publications. For US-based roles - What you'll get: • Competitive salary + annual performance-based bonus eligibility • Medical, dental, and vision insurance • 401(k) with company match • Paid time off and company holidays For Mexico-based roles - What you'll get: • Competitive salary + annual performance bonus eligibility • Christmas Bonus (Aguinaldo): 30 days • Major medical expenses and life insurance • Paid time off and holidays (per local policy) For all roles: • Professional development and growth opportunities • Opportunity to grow with a mission-driven team shaping the future of clean energy