HV/LV Electrical & Electronics
The HV/LV electrical and electronics stack is the backbone of EV energy flow and intelligence. High-voltage systems manage propulsion and charging, low-voltage systems power auxiliaries and sensors, and a growing suite of control units orchestrates everything. Efficiency gains are increasingly driven by wide-bandgap semiconductors such as SiC (silicon carbide) and GaN (gallium nitride).
High-Voltage (HV) Systems
High-voltage systems (typically 400–800V, moving toward 1000V+) provide the muscle of EV propulsion, charging, and power conversion.
Inverters (DC-AC) - Convert HV DC to AC for traction motors.
SiC MOSFETs reduce losses and cooling needs; dual/tri-motor EVs need multiple inverters.
DC-DC Converters (HV to LV) - Step HV battery down to 12V/48V.
Bi-directional designs enable V2X and flexible charging.
On-Board Chargers (OBC) - AC grid charging with PFC.
GaN modules for compact, high-frequency design.
Battery Control Unit (BCU) - Monitors/protects HV cells.
Integrates with thermal management, critical safety layer.
Charging Control Unit (CCU) - Manages charging handshake (AC/DC fast charging).
Interfaces with EVSE; enforces charging standards.
HV Cabling & Interconnects - Orange shielded cables, busbars.
Copper/aluminum supply risk; weight reduction important.
HV Protection Devices - Contactors, fuses, insulation monitors.
Specialized suppliers; essential for ISO 26262 compliance.
Low-Voltage (LV) Systems
Low-voltage systems (12V and increasingly 48V) supply intelligence, auxiliaries, and safety features across the vehicle.
LV Power Distribution - Provides energy to auxiliaries, sensors, actuators.
Transition from 12V to 48V in hybrids/EVs.
Auxiliary Electronics - HVAC compressors, pumps, fans, EPS (steering).
Converging with consumer electronics supply chain.
Infotainment & Telematics ECUs - Displays, connectivity, audio, telematics.
GaN modules for compact, high-frequency design.
ADAS / Sensor Fusion ECUs - Processes lidar, radar, camera signals.
Central to autonomy stack; sometimes in DCUs.
Body Control Module (BCM) - Lighting, windows, locks, HVAC auxiliaries.
Still common but migrating into zonal controllers.
LV Wiring Harnesses - Signal/control cabling.
OEM pain point: cost, complexity, weight.
LV Protection Devices - Relays, fuses, surge protection.
Commodity-driven but safety-critical.
Control & Computing Units
Control units orchestrate both HV and LV systems, consolidating functions and enabling software-defined vehicles.
VCU (Vehicle Control Unit): Central intelligence; manages propulsion, safety, diagnostics.
PCU (Power Control Unit): Oversees inverter logic and motor power delivery.
MCU (Motor Control Unit): Fine-grained motor speed/torque control (sometimes integrated into PCU).
DCU (Domain Control Unit): Consolidates multiple ECUs per functional domain (ADAS, body, infotainment).
BCM (Body Control Module): Legacy LV controller, now being absorbed into zonal/DCU architectures.
Gateway ECU: Bridges protocols (CAN, LIN, Ethernet, FlexRay), enforces cybersecurity, OTA updates.
Zonal Controllers (emerging): Next-gen replacements for distributed ECUs, reducing wiring harness complexity.
Cross-Cutting Enablers
Across HV, LV, and control domains, a few technologies underpin efficiency and scaling:
✓ Wide-Bandgap Semiconductors: SiC for HV propulsion and charging; GaN for LV converters and OBCs.
✓ Thermal Management Materials: Coolants, substrates, TIMs critical for inverter/OBC reliability.
✓ Communications Buses: CAN/LIN still dominate, but Ethernet-based zonal architectures are coming.
✓ Software & OTA Layers: Control units increasingly defined by software rather than hardware.
Supply Chain Bottlenecks
Key risks and dependencies affect HV, LV, and control electronics sourcing.
✗ SiC Wafer Supply - Limits inverter/PCU scaling.
✗ GaN Device Supply - Constrains OBC/DC-DC innovation.
✗ Copper & Aluminum - Impacts HV harnesses and busbars.
✗ Connector & Harness Suppliers - Long lead times, cost inflation.
✗ Thermal Materials - Critical for inverter and OBC packaging.
✗ ECU/MCU Chips - Central to VCU/DCU supply.