With the rapid development of urban air mobility (UAM), split-type flying cars, comprising a mothership and detachable aircraft, represent the frontier of transportation technology. Their power systems—encompassing high-voltage battery management, electric propulsion, thrust vectoring, and auxiliary power distribution—demand power semiconductor devices that offer exceptional efficiency, power density, reliability, and thermal performance. The selection of MOSFETs and IGBTs directly determines the performance, safety, and operational range of both the mothership and the aircraft. Addressing the stringent requirements of aviation for weight, efficiency, safety redundancy, and harsh environment operation, this article reconstructs the selection logic based on system-level scenario adaptation, providing an optimized power device solution.
I. Core Selection Principles and Scenario Adaptation Logic
Core Selection Principles
High Voltage & Robustness: For mothership battery packs (≈600-800V) and aircraft propulsion inverters, device voltage ratings must have a safety margin ≥30-50% above the maximum system voltage to withstand switching transients and fault conditions.
Ultra-Low Loss for Propulsion: Prioritize devices with minimal conduction and switching losses. For MOSFETs, low Rds(on) and Qg are critical. For IGBTs, low VCEsat and optimized switching trade-offs are key.
Package for Power Density & Cooling: Select packages (TO247, TO220F, DFN) based on power level, cooling method (liquid/forced air), and space constraints to maximize power-to-weight ratio.
Aviation-Grade Reliability: Devices must operate reliably under wide temperature ranges, vibration, and potential thermal cycling. Parameters like SOA (Safe Operating Area) and avalanche ruggedness are crucial.
Scenario Adaptation Logic
Based on the distinct power chain requirements of the split-type architecture, device applications are divided into three primary scenarios: Mothership High-Power Distribution & Charging (Energy Hub), Aircraft Main Propulsion Inverter (Thrust Core), and Aircraft Auxiliary Power & Actuator Control (Flight Support).
II. Device Selection Solutions by Scenario
Scenario 1: Mothership High-Power Distribution & Charging (10kW+) – Energy Hub Device
Recommended Model: VBPB165I80 (IGBT with FRD, 600/650V, 80A, TO3P)
Key Parameter Advantages: Fast Switching (FS) IGBT technology offers an optimal balance between low conduction loss (VCEsat=1.7V @15V) and manageable switching losses at moderate frequencies (e.g., 20-40kHz). Integrated FRD enhances system reliability. The 80A rating and robust TO3P package suit high-current DC-DC converters, onboard chargers, and main distribution switches.
Scenario Adaptation Value: The IGBT's high current density and robustness are ideal for the mothership's high-power, potentially lower-frequency conversion stages where ultimate switching speed is secondary to cost-effective high-current handling and short-circuit withstand capability. The TO3P package facilitates excellent thermal coupling to a cold plate or heatsink.
Scenario 2: Aircraft Main Propulsion Inverter (50-150kW per motor) – Thrust Core Device
Recommended Model: VBE165R20S (N-MOSFET, 650V, 20A, TO252) or VBP19R20S (N-MOSFET, 900V, 20A, TO247) for higher voltage designs.
Key Parameter Advantages: Utilizes Super Junction Multi-EPI technology, achieving a low Rds(on) of 160mΩ (VBE165R20S) or 205mΩ (VBP19R20S). The 650V/900V rating provides ample margin for 400-600V aircraft battery systems. Low gate charge enables high-frequency PWM operation (50-100kHz+), crucial for minimizing motor current ripple and filter size.
Scenario Adaptation Value: The super junction MOSFET's high switching frequency capability allows for compact, lightweight motor drive inverter designs with high control bandwidth for precise thrust vectoring. The TO252/TO247 packages offer a good balance between current capability, thermal performance, and weight. Multiple devices can be paralleled easily to scale current.
Scenario 3: Aircraft Auxiliary Power & Actuator Control (<3kW) – Flight Support Device
Recommended Model: VBGQF1806 (N-MOSFET, 80V, 56A, DFN8(3x3))
Key Parameter Advantages: Features SGT (Shielded Gate Trench) technology, delivering an ultra-low Rds(on) of 7.5mΩ at 10V Vgs. The 56A continuous current rating far exceeds the needs of most auxiliary loads (avionics, pumps, servos, lighting) on a 48V or lower aircraft auxiliary bus.
Scenario Adaptation Value: The ultra-compact DFN8 package minimizes weight and PCB space—a critical factor in aircraft design. Ultra-low conduction loss maximizes efficiency for always-on or frequently switched auxiliary loads, conserving precious battery energy. Can be used in DC-DC converters, PMSM servo drives for flight controls, and power distribution units (PDUs).
III. System-Level Design Implementation Points
Drive Circuit Design
VBPB165I80 (IGBT): Requires a dedicated high-current gate driver with negative turn-off voltage for robustness. Desaturation detection is recommended for short-circuit protection.
VBE165R20S / VBP19R20S (HV MOSFET): Pair with high-speed, high-current gate driver ICs. Careful layout to minimize power loop inductance is essential to limit voltage spikes. Use gate resistors to control di/dt and dv/dt.
VBGQF1806 (LV MOSFET): Can be driven by standard gate driver ICs or, for smaller loads, directly from microcontroller PWM outputs with a buffer. Attention to PCB layout for thermal vias is key.
Thermal Management Design
Mothership (VBPB165I80): Requires a substantial heatsink, likely liquid-cooled or with forced air. Thermal interface material (TIM) selection is critical.
Aircraft Propulsion (VBE165R20S/VBP19R20S): Implement direct cooling via a cold plate attached to the inverter module baseplate. Consider phase-change materials or forced air for peak power handling.
Aircraft Auxiliary (VBGQF1806): Rely on a large PCB copper pour with multiple thermal vias connecting to internal ground/power planes for heat spreading. Conformal coating may be needed.
EMC and Reliability Assurance
EMI Suppression: Use snubber circuits across HV MOSFETs/IGBTs. Implement proper filtering at inverter input and output. Shield sensitive control lines.
Protection Measures: Implement comprehensive overcurrent, overtemperature, and overvoltage protection at the system level. Use TVS diodes for busbar and gate protection. Incorporate redundancy for critical flight control actuators.
Vibration & Environment: Conformally coat PCBs. Use mechanical locking or potting for high-vibration areas. Select components with wide operating temperature ranges.
IV. Core Value of the Solution and Optimization Suggestions
This scenario-adapted power device selection solution for split-type flying cars provides a balanced approach across the energy storage, propulsion, and support systems of both vehicle segments. Its core value is threefold:
Optimized Performance-to-Weight Ratio: By matching the most suitable device technology (IGBT for high-power/low-frequency, Super Junction MOSFET for high-frequency propulsion, SGT MOSFET for ultra-efficient auxiliary power) to each functional block, the solution minimizes total system losses and weight. This directly translates to extended flight range and improved payload capacity.
Layered Safety and Redundancy: The inherent ruggedness of the selected IGBT and MOSFETs, combined with the proposed system-level protection strategies, forms a foundation for functional safety (potentially up to ASIL levels). The separation of power domains (mothership vs. aircraft, propulsion vs. auxiliary) enhances system resilience.
Scalability and Technological Pathway: The selected devices are based on mature, high-volume silicon technologies offering a reliable and cost-effective entry point. The architecture readily accommodates future migration to wide-bandgap devices (SiC MOSFETs for propulsion, GaN for ultra-high-frequency auxiliary converters) as costs decrease and power density requirements increase, protecting the design investment.
In the power system design of split-type flying cars, the selection of MOSFETs and IGBTs is a cornerstone for achieving the necessary efficiency, power density, safety, and reliability. This scenario-based solution, by aligning device characteristics with specific mission profiles and integrating robust drive, thermal, and protection design, provides a actionable technical roadmap. As UAM technology evolves towards certification and commercialization, power electronics will continue to be a key enabler. Future focus should be on integrating more intelligent monitoring and health management functions at the module level and adopting next-generation semiconductors to push the boundaries of what is possible in aerial mobility, ensuring both performance and passenger safety in this transformative mode of transportation.

Detailed Topology Diagrams