Lead Controls Engineer - Power Electronics

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Recruiting agencies: Proper Voltage does not accept unsolicited candidate submissions. Please do not contact any employees directly unless you have an existing engagement with the company.

About Proper Voltage

Proper Voltage is unlocking the next generation of battery technology across robotics, data centers, and defense.

We're building intelligent battery systems that make advanced chemistries (sodium-ion, lithium-titanate, lithium-silicon) work in products that were never designed for them. Humanoid robots can upgrade power systems without redesigning their entire platform. Data centers get safer, cheaper backup power. Drones and autonomous vehicles get higher energy density without lengthy integration cycles.

If you want to work on hard engineering problems that matter this is the place.

Job Overview

Proper Voltage designs and builds safety-critical battery energy storage systems. This role leads control design for our bidirectional DC/DC power conversion stage — the current and voltage loops, mode transitions, and protection behavior of multiphase interleaved converters — from plant model through validated hardware.

This role sits where power electronics control meets software. You will model the plant, design and discretize the compensators, and prove them in closed-loop simulation running the actual control code. Then you hand the firmware team a design they can implement without guesswork: coefficients, scaling, sample timing, delay budget, limits, and the margins the implementation must preserve.

You will work as a pair with our Lead Firmware Engineer – Power Conversion Control. You own what the loop should do and why; they own how it runs on the silicon. When measured loop gain disagrees with the model, you find out which one is wrong.

What you'll do

• Control design for four-switch buck-boost power stages and successor topologies: current and voltage loops, feedforward, multiphase interleaved operation, and phase current balancing.
• Plant models and closed-loop simulation models for each converter, kept current with the hardware and used as the reference for firmware verification.
• Operating mode and protection behavior: the transition logic, thresholds, and response-time requirements that firmware implements.
• Control design specifications — the documented interface between control design and firmware implementation.
• Control loop verification: model-to-measurement correlation, loop gain and stability margin characterization, transient response, and stability across the full operating envelope.
• Control performance evidence supporting UL 1973, UL 1998, and UL 9540 certification.

Responsibilities

• Derive small-signal plant models for buck, boost, four-switch buck-boost, and multiphase interleaved topologies, including coupled-inductor effects, right-half-plane zeros, and operating-point variation across the envelope.
• Design compensators (PID, type II/III, 2p2z/3p3z) and feedforward paths to meet bandwidth, phase margin, and gain margin targets for average current mode inner loops and voltage outer loops.
• Discretize designs for digital implementation, accounting for sampling, zero-order hold, computational delay, and PWM update latency, and specify the sample rates and delay budget the firmware must meet.
• Build closed-loop converter models in PLECS and/or MATLAB/Simulink from scratch, and use SPICE-class tools for switching-cell verification where averaged models fall short.
• Write code for simulation and analysis: scripted parameter sweeps, component-tolerance and worst-case analysis, and automated stability checks across the operating envelope in Python or MATLAB.
• Run the production C control code inside the simulation (PLECS C-Script/DLL blocks or Simulink S-functions) to verify the firmware implementation against the design before it reaches hardware.
• Define operating mode behavior — constant current, constant voltage, constant power, current limit, soft-start, buck-to-boost transition, phase shedding, and charge/discharge direction reversal — including transition conditions and bumpless transfer requirements.
• Define protection thresholds and response-time requirements for cycle-by-cycle current limit, overvoltage, undervoltage, and thermal derating, in coordination with hardware and firmware.
• Translate each design into a specification firmware can implement directly: block diagrams, difference equations, coefficients, fixed-point scaling guidance, saturation and anti-windup limits, and expected margins.
• Work alongside the firmware team through implementation, code review, and bench debug, and review firmware control code for fidelity to the design.
• Measure loop gain by network analyzer injection, step-load transient response, and ripple on hardware, and correlate results against the model.
• Contribute to hardware design reviews covering current and voltage sensing, anti-aliasing filters, magnetics, and gate drive as they affect control.
• Serve as technical lead for converter control design: set design and verification practices and review other engineers' control work.
• Author control specifications and verification evidence to a standard that withstands certification-body review.

Required Qualifications

• BS in Electrical Engineering or equivalent demonstrated capability.
• Six or more years designing control systems for switched-mode power converters.
• Direct, hands-on experience designing control loops for switched-mode power converters that reached validated hardware. You can name the topology, control mode, switching and sampling frequencies, compensator structure, and achieved crossover and phase margin for a converter you personally designed.
• Working command of small-signal modeling (state-space averaging or equivalent) and frequency-domain design: Bode and Nyquist analysis, crossover, phase and gain margin, and right-half-plane zeros.
• Working command of discrete-time control: s-to-z mapping (bilinear/Tustin, zero-order hold), the effect of sampling and computational delay on phase margin, aliasing, and quantization.
• Fluency in PLECS or MATLAB/Simulink, with the ability to build a converter model rather than only run an existing one.
• Proficiency in Python or MATLAB scripting for simulation automation and data analysis.
• Working proficiency in C: able to read and write control code, run it in simulation, and judge whether a firmware implementation matches the design.
• Understanding of the digital implementation constraints that shape a design: PWM-triggered ADC sampling, update latency, fixed-point range and resolution, and ISR timing budgets.
• Independent lab capability with oscilloscopes, isolated and differential probes, current probes, electronic loads, bidirectional supplies, and a network or frequency response analyzer for loop gain measurement.
• A track record of written control design specifications that another engineer implemented successfully.

Preferred Qualifications

• MS or PhD in Electrical Engineering with a focus in power electronics or control systems.
• Bidirectional and multiphase interleaved converter control, including coupled inductors, current sharing, and phase balancing between paralleled phases.
• Average current mode control specifically, as distinct from voltage mode or peak current mode, and feedforward design for four-switch buck-boost converters.
• Large-signal behavior: buck-to-boost mode transitions, discontinuous conduction boundaries, saturation recovery, and limit cycles.
• Wide-bandgap power stages (GaN, SiC) and their effect on control — sense chain noise, blanking, and dead-time sensitivity.
• Digital power controllers such as dsPIC33C, TI C2000, or STM32G4, at the level of knowing what their PWM and ADC architectures allow.
• Hardware-in-the-loop or real-time simulation platforms such as PLECS RT Box, Typhoon HIL, or OPAL-RT.
• Python numerical tools (NumPy, SciPy, python-control) for control analysis.
• Battery energy storage, EV charging, photovoltaic inverter, or grid-interactive converter experience, including BMS interaction such as current limit negotiation and precharge.
• Functional safety and certification exposure: IEC 61508 concepts, UL 1973, UL 1998, UL 9540, and FMEA.
• Version control and code review applied to models and analysis scripts, not only firmware.

Compensation & Benefits

• Salary range: $150,000 – $175,000 depending on experience and qualifications.

• Equity options as part of the compensation package.

• Comprehensive healthcare benefits (medical, dental, vision).

• Generous paid time off and paid holidays (PTO) policy.

Ready to work on power systems that matter? Let's talk.