I. Current Status of the eVTOL Industry TFly
Strategic Positioning and Airworthiness Certification: The low-altitude economy has been explicitly designated as a strategic emerging industry by the state. The sector is now transitioning from the initial concept validation phase into the deep waters of "airworthiness certification and scaled-up delivery."
On July 22, the Airworthiness Certification Department of the Civil Aviation Administration of China (CAAC) published the "First Batch of Compliant Enterprises for Airworthiness Certification of Civil Manned eVTOL." Four companies, including XPeng AeroHT, EHang, Volant, and AutoFlight, were selected. These selected enterprises will benefit from policies such as simplified certification processes, priority processing of application materials, and mutual recognition of phased test results across batches, aiming to shorten the airworthiness certification cycle for manned eVTOL models and accelerate commercialization.
Market Growth Expectations: According to forecasts by market research firm Market&Markets, the global eVTOL market size will reach $3.19 billion by 2031 and $5.08 billion by 2035, with a compound annual growth rate (CAGR) of 12.3% from 2025 to 2035.
Industrial Driving Effect: The low-altitude economy is not only reconstructing three-dimensional transportation networks such as Urban Air Mobility (UAM) and high-end logistics, but also exerting an extremely strong driving effect on upstream high-value supply chains. As the heart of the eVTOL, the power system accounts for approximately 40% of the total aircraft cost. The demand from the low-altitude economy has driven the expansion of the high-end power semiconductor (especially Silicon Carbide, SiC) and high-energy-density battery markets.
II. Different Technical Routes and Representative Manufacturers of eVTOL
1. Multi-Rotor Models
·Technical Features: No fixed wings, relatively simple structure, relying on multiple hovering propellers to directly provide lift and thrust. It features high hovering efficiency but is limited in aerodynamic efficiency and range (typically <30km).
·Application Scenarios: Low-altitude cultural tourism and sightseeing, urban short-distance air taxis (UAM), and emergency rescue.
·Representative Manufacturers: EHang (the EH216-S model has obtained airworthiness certification).
·Semiconductor Demand Perspective: Multi-rotors adopt a typical Distributed Electric Propulsion (DEP) architecture, where each motor requires independent electronic control. Once a single motor fails, the electronic control system must complete power redistribution within milliseconds. This requires power semiconductors to possess extremely high high-frequency dynamic response capabilities and outstanding thermal dissipation performance.
2. Compound Wing Models (Lift & Cruise)
·Technical Features: Combining the advantages of fixed-wing and multi-rotor designs, it independently carries lift propellers for vertical takeoff and landing, and thrust propellers for forward flight. It balances vertical takeoff and landing with fixed-wing forward flight, featuring high technological maturity.
·Application Scenarios: Island/cross-sea and cross-city urgent logistics, emergency rescue, and short-to-medium intercity passenger transport (100-200km).
·Representative Manufacturers: AutoFlight, Volant, and T-Fly.
·Semiconductor Demand Perspective: This solution mostly follows the commercialization path of "cargo first, passenger later." The airworthiness redundancy requirements for pure cargo drones are moderately reduced from stringent aviation-grade to high-end industrial/automotive-grade. This shifts its semiconductor demand towards achieving the optimal cost balance of mixed SiC and high-end IGBT applications under the premise of meeting certain reliability standards.
3. Tilt-Rotor Models
Video Source: Joby Aviation
·Technical Features: The rotor shaft can tilt, providing lift during takeoff and landing, and tilting to provide thrust during forward flight. It has the highest mechanical structure and technical difficulty, but can achieve the longest range (>200km) and the fastest cruising speed.
·Application Scenarios: Cross-city cluster business commuting and trunk low-altitude passenger transport.
·Representative Manufacturers: Joby Aviation, Archer, Aerofugia (AE200), and TCab Tech.
·Semiconductor Demand Perspective: During the transition phase from vertical takeoff and landing to forward flight, the system will encounter extreme power changes and thermal loads. This harsh operating condition poses physical limit requirements for lightweight, high-temperature resistance, and extremely low switching losses, making this route absolutely dependent on high-voltage Silicon Carbide (1200V SiC) modules.
4. Other Black Technologies
·Split Land-Air Amphibious: Taking XPeng AeroHT's "Land Aircraft Carrier" as an example, it features a split design of "land-moving mothership + flying body," targeting C-end private consumption. Its supply chain is deeply bound to domestic automotive-grade electronic control leaders, utilizing the extremely mature New Energy Vehicle (NEV) three-electric supply chain, demonstrating the large-scale spillover effect of automotive-grade semiconductors and ultimate cost control advantages.
·DEVT Solution (Distributed Electric Ducted Fan Vectoring Thrust): Taking Lilium Jet before its bankruptcy restructuring as an example. Its extremely small ducted fans lead to a very high "disk loading," requiring peak power2 to 3 times that of open propellers during hovering and takeoff/landing phases. The power consumption and heat generation during hovering show a terrifying exponential growth. This brings huge pain points to thermal management in confined spaces and is also a physical limit challenge for high-end SiC modules and ultimate thermal packaging. The main advantage of this solution is that it can significantly reduce rotor noise.
III. Performance Requirements of eVTOL Electric Drive Systems for Power Semiconductors
1. Power Load Curve Characteristics of the Power Supply
During the eVTOL flight cycle, the power load of the electric drive system shows a clear "pointed at both ends, flat in the middle" characteristic:
·The vertical takeoff phase requires completely counteracting gravity, generating an extremely large transient peak current;
·After entering forward cruise, the power drops sharply and maintains a low-power stable output;
·During vertical landing, a secondary peak current appears again.
This extreme surge current impact causes severe fluctuations in the chip junction temperature. It not only requires the main drive inverter to have extremely low switching losses to control heat generation, but also poses strict physical tests on its thermal fatigue resistance life and transient tolerance for extremely high voltage (overload margin) capabilities.
2. Lightweight Requirements
In aircraft design, "every gram of weight consumes range," which poses extreme requirements for the "power-to-weight ratio" of power semiconductors. Since it needs to overcome gravity for takeoff and landing, the eVTOL electronic control system must achieve a power density far exceeding automotive-grade levels (reference value, >15 kW/kg). This makes SiC a mandatory choice for the main drive of eVTOL.
3. Aviation-Grade Reliability
Compared to the automotive-grade safety standards for NEVs (ISO 26262/AEC-Q101, with a fault tolerance in the order of 10^(-6)), the eVTOL power system must leap to the highest aviation-grade airworthiness standards (hardware DO-254 / environment DO-160G), requiring the catastrophic failure rate to be strictly controlled below 10^(-9)/flight hour. To this end, power modules have undergone large-scale technical improvements in packaging processes to enhance the thermal fatigue limit; at the same time, multi-redundancy architectures such as "dual three-phase motors + dual independent electronic control channels" have been fully popularized in the electronic control architecture.
IV. Power Semiconductors in Other Application Scenarios of eVTOL
1. Application Scenarios of GaN
·Step-Down DC-DC Converters: When converting the 800V high-voltage bus to the 28V/48V low-voltage network required by the avionics system, GaN, with its MHz-level ultra-high-frequency switching characteristics, greatly reduces the volume of transformers and magnetic components, meeting the extreme lightweight demands of the avionics system.
·LiDAR Driver Chips: LiDAR emits infrared light (generated by GaAs/InP lasers), but driving these lasers requires extremely narrow (nanosecond-level) high-peak current pulses. GaN serves here as an ultra-high-speed power switch, which is the absolute core hardware for achieving nanosecond-level narrow pulses and improving low-altitude obstacle avoidance and 3D ranging accuracy.
2. Application Scenarios of Si-IGBT
·Auxiliary High-Voltage Drive: Traditional 1200V automotive-grade Si-IGBTs have great cost-effectiveness in auxiliary circuits such as thermal management liquid-cooled water pumps and high-voltage air conditioning compressors, because these low-frequency, medium-power devices do not need to pursue the extreme high-frequency characteristics of SiC.
·Hybrid Power Modules: In the main drive systems of cost-sensitive models such as heavy-load cargo drones, using "Si-IGBT + SiC SBD (Silicon Carbide Schottky Barrier Diode)" hybrid packaging modules can reduce losses while significantly cutting BOM costs, possessing strong transitional commercial value.
3. Application Scenarios of Si-MOSFET
·Solid State Power Controllers (SSPC / e-Fuse): Replacing traditional mechanical circuit breakers to achieve microsecond-level high-voltage fault safety cutoff, with vibration resistance and no mechanical wear.
·BMS (Battery Management System): Responsible for active/passive balancing control of battery cells and active safety protection cutoff switches.
·Pneumatic Control Surface Micro Servo Motors: Used for precise control of wing rudder surfaces and fine-tuning actuators of tilt mechanisms.
V. Industrial Chain Models of Power Semiconductors in the Low-Altitude Economy Field
China Local: Spillover of the NEV Industrial Chain
China's low-altitude power semiconductor industrial chain demonstrates a highly distinctive "automotive-grade transfer + aviation-grade airworthiness secondary transformation" dimensional reduction attack model. Local enterprises make full use of the extremely competitive and mature domestic NEV 800V SiC industrial base, jointly develop with OEMs, and rapidly shorten the design and mass production landing cycle through large-scale capacity spillover, bringing the originally high aviation-grade pricing down to a more competitive range.
Europe and America: Two Divergent Models
The European and American markets, lacking a complete NEV industrial chain, have moved towards polarization:
·OEM Self-Development + Vertical Integration: Represented by Joby, choosing to self-develop high-power aviation inverters and deeply binding with large companies such as Toyota Denso at the underlying level, building extremely high software and hardware engineering landing and airworthiness closed-loop barriers.
·Reliance on Traditional Aviation Tier 1: The electric drive system deeply relies on highly integrated solutions provided by traditional aviation giants.
VI. Industry Challenges and Potential Risks
1.Non-Standard Technology and Airworthiness Certification: Currently, under the conditions of coexistence of heterogeneous architectures for multiple models + relatively fast design/technology updates, the industry lacks unified certification specifications and technical standards. This leads to an extremely long airworthiness certification cycle (usually 3-5 years) and high hardware verification and testing costs, which constitutes the biggest commercialization challenge in the short term.
2.Noise Issues: The current mainstream open propeller design has relatively large noise defects. In suburban areas or pure industrial application scenarios, such noise is still within controllable and acceptable ranges; however, once it enters the urban interior with high-density buildings and population aggregation, the physical noise pollution it generates is extremely easy to cause serious interference to public life. Limited by the principles of aerodynamics, this is a technical pain point that is currently extremely difficult to overcome for urban low-altitude transportation.
3.Game of Airspace Security Control: The opening of low-altitude airspace, on the one hand, needs to prevent safety issues caused by air traffic accidents, and on the other hand, lies in considerations of military defense and national security. The access of massive civilian aircraft to the low-altitude will pose challenges to the existing air defense identification system, the low-slow-small target interception network, and the security of national critical infrastructure.
From this perspective, the large cities that most need low-altitude transportation may instead adopt more conservative control policies, while short-distance shipping between cities and industrialized demand scenarios in the suburbs may progress faster.
VII. Sorting Out the Supply Chain Relationships of Some Representative Manufacturers at Home and Abroad
Reference Materials
1. Official materials of each company
2. China Post Securities Research Report "Low-Altitude Economy Special Issue 3: Detailed Deconstruction of eVTOL"
3. Guoxin Securities Research Report "Low-Altitude Economy Industry Special Issue Series 2: Market Space, Technology Trends, and Industrial Chain Opportunities of the eVTOL Power System"