Autonomous vehicles demand more than just smarter software and faster compute. They demand systems that can endure – that keep functioning even when faults occur. And at the foundation of this endurance is one of the most overlooked elements in vehicle design: Power.

In Level 3 and above systems – where the vehicle, not the human, is expected to stay in control – even a brief power interruption can mean resets, loss of safety functions, or degraded perception. In this context, power electronics aren’t just about delivery – they’re about survivability.

Yet, power systems are still too often treated as static utilities. That mindset must change.

From Simplicity to System-Critical Complexity

A few decades ago, automotive power was straightforward. A single 12V system ran basic loads – lights, ignition, and accessories. Ring terminals handled the connections. Cloth-wrapped wiring looms carried current with little concern for speed, redundancy, or noise.

Today, a vehicle must manage:

• 800V propulsion systems
• 400V battery charging
• 48V subsystems for thermal control
• 12V and 3.3V rails for ECUs, sensors, safety modules, and infotainment

All of it must operate under predictive diagnostics, fail-operational constraints, and functional safety compliance – while also delivering power that is efficient, secure, and always available.

Power delivery is no longer a background task. It’s a system – and it needs to think.

Power Systems Are No Longer Passive

Modern E/E architectures demand that power systems:

• Monitor thermal and electrical behaviour in real time
• Predict and isolate faults before they cascade
• Execute autonomous recovery and rerouting strategies
• Meet safety (ISO 26262) and cybersecurity (ISO/SAE 21434) standards
• Communicate diagnostic data across domains

These demands transform the role of DC-DC converters and battery interfaces. No longer simple regulators, they now sit within the intelligent safety fabric – expected to coordinate with BMS inputs, protect zonal stability, and ensure continuity across increasingly decentralised vehicle platforms.

As Professor Valeria Bertacco of the University of Michigan put it,

“Cars have been seen as computers on wheels for a while, but to achieve full autonomy, they need to be more like traveling data centers.”

– University of Michigan Engineering News, 2025

That shift doesn’t only impact software and compute. It extends to every system that enables them – including power.

What It Means to Fail-Safe – and Keep Operating

Fail-safe is no longer enough if it only means shutting down gracefully.

In a Level 3+ vehicle, “fail-safe” means: detect the fault, isolate it, and continue operating.

This redefinition has architectural consequences. It raises the bar for:

• Embedded software logic
• Diagnostic strategies
• Redundant routing paths
• Test coverage using model-in-the-loop (MIL), software-in-the-loop (SIL), and hardware-in-the-loop (HIL) platforms

Power systems must not only respond quickly – they must anticipate. They must recover independently, without waiting for central intervention.

A Perspective from the Field

This thinking shaped the design of a recent DC-DC converter system developed for a highly autonomous vehicle program with a leading German OEM.

The system served as a fallback power unit – responsible for instantly taking over if the primary source failed. It was built to:

• Maintain instant ON/OFF response
• Coordinate capacitor pre-charge and boost-mode transitions via BMS input
• Meet ASIL-D (hardware) and ASIL-B (software) safety levels
• Enable UDS- and OBD-based diagnostics with secure communication
• Pass validation through 750+ mapped requirements and 99% test automation in HIL environments

At Acsia, our role focused on software architecture, diagnostics integration, safety implementation, and test automation. The result was not a traditional converter – it was a resilience layer, embedded deep into the vehicle’s power backbone.

The Next Frontier in Power Electronics

As vehicle platforms evolve toward central compute, zonal control, and over-the-air orchestration, power systems must evolve in parallel. They must be:

• System-aware
• Testable and traceable
• Secure, predictive, and fail-operational

Because power is no longer about voltage. It is about availability, continuity, and autonomous recovery – especially when the rest of the vehicle is counting on it.

The question for system architects is no longer how do we deliver power safely? It is: How do we design power systems intelligent enough to protect autonomy – not just enable it?

At Acsia, we’re contributing to that answer – building systems that sense, decide, and recover at the electrical core.

Let’s make power think. Because autonomy depends on it.

Request a Demo

If you’d like to see how Acsia supported the German OEM’s highly autonomous vehicle platform that needed a DC-DC power conversion system which could act as a fail-safe backup power source, schedule a meeting now.