Principal Engineer, Power Systems Controls

TAR’s mission is to power intelligence for the world. We are building the world’s first off-grid power plant for data centers powered by renewable technologies.

We firmly believe AI should be built in the US for the benefit of all people. For that, power must be fast, clean and cheap. We are singularly focused on delivering GW-scale power faster than anyone has ever done, by rethinking every layer of the stack.

To deliver on this vision, TAR manufactures, deploys and operates off-grid energy assets with a renewable backbone. We vertically integrate to solve every bottleneck, from racking systems to power electronics to dispatch algorithms to on-site construction.

Leave your mark by powering the future of civilisation-scale energy infrastructure.

We hire people who care deeply about this problem space. If that is you, please apply!

We are a team of seasoned operators run by founders who previously scaled a company to over 80 people and $350M in annual sales. We know how to operate and we move fast.

We are working directly with one of the largest compute providers to make our vision come true and plan to deploy 5GWs by 2028.

TAR is both a hardware and software company, we are building out massive, critical, physical infrastructure.

We operate on…

• High ownership. High Agency. Own project end-to-end. Great people don’t need to be managed.

• Speed. We achieve great things on incredible timelines. We always push ourselves to go faster.

• First principles. No ego. No hierarchy. Challenge every assumption.

• Passion. Solving the energy problem is one of the largest challenges that faces the world now and in the future. We put in long hours and hard work to solve this.

As Principal Engineer, Power Systems Controls, you support two critical areas: how the power electronics behave in an inverter-dominant island, and the control architecture that ties every asset together. You translate architecture into single-lines, interrogate the grid-forming PCS and BESS down to the control level, define where OEM firmware ends and a separate system-level controller begins, and validate that the integrated plant holds frequency and voltage on its own, while powering a data center load 24/7, with no utility behind it. The hardest problems on this project live in controls and protection under islanded conditions, and this role supports the engineering answer to them. You drive the day-to-day controls and power engineering under the VP of Power Systems Control & Grid Integration.

Two scope notes on what this role is and is not. First, we integrate utility-scale OEM equipment; we do not design power converters at the silicon level. We need someone who understands converter internals well enough to push OEMs hard on grid-forming behavior, ride-through, and protection, not someone who wants to lay out gate drivers. Second, you support the control architecture and its validation (the control philosophy, the OEM-firmware-versus-MGC boundary, the MGC and EMS functional specs, and proof that the integrated island is stable). A controls and automation engineer plus the MGC and EMS vendors carry implementation under the architecture you help set.

• Control architecture and multi-vendor integration
  Support the control hierarchy architecture development for the islanded plant. Author the control philosophy, define where OEM grid-forming firmware ends and a third-party microgrid controller (MGC/PPC) begins, write the functional specifications for the MGC and EMS, and support multi-vendor controls integration end-to-end so no function falls into a gap between vendors.

• Dynamic system modeling and power electronics integration
  Support specification, evaluation, and validation of grid-forming inverters and BESS PCS. Develop and validate detailed time-domain models of battery storage systems and hybrid PV–BESS configurations in tools such as PSCAD, DIgSILENT PowerFactory, and PSS/E. Model and verify GFM control behavior, fault response, ride-through, and inverter-to-inverter interactions in an IBR-dominant plant with limited fault current, including EMT/PSCAD validation against usable OEM models. Create models of power electronic converters (multilevel, modular, etc.) and simulate their electrical dynamics to inform OEM technical pushback.

• Islanded system studies and protection
  Run and review islanded power-system studies: load flow, short-circuit, load smoothing, and transient/load-step stability for a continuous high-density IT load. Grid code compliance and stability
  Conduct grid interconnection studies to ensure designs meet standards (e.g., IEEE 1547, UL 1741, IEEE 2800). Perform stability and transient analyses on microgrids and utility-scale systems to verify secure operation under disturbances.

• Control strategy and controller design
  Develop and refine control strategies for inverters and converters to meet performance and safety requirements. Where architecture calls for it, translate control concepts into working code: implement control algorithms in MATLAB/Simulink.

• HIL validation and field testing
  Integrate control software with real hardware platforms and perform Hardware-in-the-Loop (HIL) simulations using platforms such as Typhoon HIL. Validate converter prototypes and battery systems in lab tests, troubleshoot hardware issues, and refine models based on experimental data. Write commissioning and validation test plans; support bring-up, acceptance testing, and field troubleshooting at the pilot and beyond.

• System-level design and reliability
  Contribute to the overall power system architecture. Participate in design reviews and conduct Failure Mode and Effects Analysis (FMEA) on system components and controls to identify potential failures and enhance reliability.

• OEM engagement and program support
  Drive OEM technical engagement on PCS, BESS, and controls. Track FEOC-compliant equipment options where ITC eligibility is at stake. Support permitting, interconnection, and the OE/IE with the controls and power systems analysis they require.

• Cross-functional collaboration
  Work closely with adjacent teams to align modeling, control, and implementation efforts. Collaborate with hardware testing engineers to refine models and incorporate lab findings into system design.

• M.Sc. or Ph.D. in Controls Engineering, Power Systems, Power Electronics, Electrical Engineering, or a related field. Strong grasp of core power systems and controls engineering principles is essential.

• 7-10+ years in utility-scale solar, BESS, or power electronics, with hands-on ownership of SLDs and power-conversion integration.

• Proficiency and hands-on modeling experience with simulation tools such as PSCAD, DIgSILENT PowerFactory, PSS/E or equivalent.

• Working knowledge of grid-forming versus grid-following inverter architecture and BESS PCS behavior. Able to read control specs critically, not just datasheets.

• Strong NEC, UL 1741-SB knowledge for PV, AC/DC coupling, and energy storage integration.

• Experience with islanding controls, microgrid EMS/MGC, and inverter/PCS integration.

• Able to model islanded systems, transient load response, and short-circuit/coordination studies, and to explain why islanded fault behavior breaks conventional overcurrent protection.

• Hands-on experience modeling inverter-based resources and converter topologies (e.g., grid-tied inverters, DC–DC and AC–DC converters).

• Proficient in Python and MATLAB/Simulink for algorithm development and data analysis. Experience with Fortran or other scientific languages common in legacy grid simulators is a plus.

• Extreme attention to detail with a bias for speed and rapid iteration.

• Direct islanded, off-grid, or BTM microgrid experience.

• Field-validated GFM behavior, fault response, ride-through, and inverter-to-inverter interactions in a real IBR-dominant or islanded plant with limited fault current.

• Experience with EMT modeling of utility-scale PV+BESS powering a large variable load.

• Familiarity with distributed energy interconnection standards (e.g., IEEE 1547, IEEE 2800 series, UL 1741) and anti-islanding requirements for inverter-based resources.

• Knowledge of renewable energy system features such as maximum power point tracking (MPPT), DC arc-fault detection, and design of modular or multilevel converters.

• Experience with hardware-in-the-loop testing tools (Typhoon HIL, OPAL-RT, or similar) for validating power system controllers and battery systems.

• Proven ability to convert Simulink/PLECS control models into optimized embedded C code (e.g., using MATLAB Embedded Coder) for deployment on digital controllers.

• Written and executed commissioning/validation test plans and troubleshot bring-up in the field.

• Test-like-you-fly culture (Tesla Energy, Fluence, SpaceX, Array, Nextracker, or comparable) where validation rigor is the norm.

• Up to $15K relocation bonus

• Unlimited PTO

• Health, Dental, Vision insurance

• $1K monthly stipend for meals