Domain Centralised Electrical/Electronic Architecture (Domain Centralised EEA)

Domain Centralised Electrical/Electronic Architecture (Domain Centralised EEA) represents the second phase in the evolution of automotive electrical and electronic architectures, bridging the transition from distributed systems to centralised computing. By introducing the core concept of the Domain Control Unit (DCU), functions previously scattered across dozens or even hundreds of standalone ECUs are grouped by functional domains, uniformly managed and executed by high-performance domain controllers.

If a conventional distributed architecture assigns a standalone "brain" (ECU) to every individual feature, a domain centralised architecture consolidates these units into several "departments" (domains) by function, overseen by dedicated "department managers" (domain controllers) to significantly improve overall vehicle management efficiency.

Core Characteristics: From Operating in Silos to "Department Managers"

The most definitive advancement in a domain centralised architecture is the introduction of the Domain Control Unit (DCU). As an integrated system combining high-performance processors, operating systems, and application software, it takes over the computing and control tasks of all ECUs within its respective functional domain. A standard domain classification proposed by Bosch includes:

• Powertrain Domain: Manages powertrain systems, including the engine, electric motors, and battery pack.

• Chassis Domain: Governs vehicle dynamic systems such as braking, steering, and suspension.

• Body Domain: Oversees body and comfort electronics, including doors, windows, lighting, and air-conditioning.

• Cockpit Domain: Integrates smart cabin interaction systems, such as the digital instrument cluster, central infotainment display, and head-up display (HUD).

• Autonomous Driving Domain: Handles core ADAS and autonomous driving processes, including perception, decision-making, and path planning.

For instance, Volkswagen ID. models underpinned by the MEB dedicated EV platform utilise three central computing units: ICAS1 (Body Control Domain), ICAS2 (Advanced Driver Assistance/Autonomous Driving Domain), and ICAS3 (Smart Cockpit Domain), achieving centralised domain-level vehicle management.

Core Value: Cost Reduction, Efficiency Gains, and Software-Hardware Decoupling

The transition to a domain centralised architecture delivers multi-faceted benefits. Substantial reduction in ECU count: Moving from a distributed setup to a domain-controlled architecture allowed XPeng to consolidate over 30 ECUs into just four domain controllers, streamlining the vehicle's entire network topology. Significantly enhanced communication bandwidth: Deploying Automotive Ethernet as the backbone network instead of conventional CAN bus systems facilitates high-speed data transmission for sensors such as cameras and radars, meeting the rigorous bandwidth demands of Level 2 to Level 3 automated driving systems. Optimised wiring harness and manufacturing costs: By adopting a domain centralised architecture, the wiring harness length in the Tesla Model S was reduced to 3 kilometres, delivering marked simplification over traditional vehicle wiring.

More importantly, a domain centralised architecture lays the groundwork for software-hardware decoupling and full-vehicle over-the-air (OTA) updates. The separation of software from underlying hardware empowers carmakers to continuously enhance vehicle capabilities via remote updates without physical hardware modifications, realising the true vision of the Software-Defined Vehicle (SDV).

Industry Standing and Future Evolution

Domain centralised architecture is a critical milestone in Bosch's EEA evolutionary roadmap, widely identified as the second phase situated between legacy distributed layouts and emerging central computing architectures. It also stands as the mainstream architecture widely adopted across the global automotive industry between 2022 and 2025.

Nonetheless, domain centralised architecture presents inherent limitations, including data transmission latency between individual domain controllers and constrained cross-domain coordinated control. Consequently, the industry is advancing towards "domain fusion" and ultimately the target "central computing + zonal control" architecture, unlocking higher levels of centralised compute power and seamless vehicle-wide coordination.