Enabling Industrial E-Mobility With SiC Technology

This article is published by EEPower as part of an exclusive digital content partnership with Bodo’s Power Systems.

E-mobility, also known as electric mobility or electromobility, refers to using electric propulsion to drive a vehicle. Wide bandgap semiconductors like silicon carbide are used in vehicle inverters to manage the power transfer from the energy source (e.g., battery or hydrogen fuel cell) to the electric motor. Although most widely associated with passenger electric vehicles (EVs), Wolfspeed expands the term to “industrial e-mobility” to encompass the range of applications across land, sky, water, and railways that run on all types of electric platforms.

 

Image used courtesy of Adobe Stock

 

While some industrial e-mobility segments are emerging, such as electric vertical take-off and landing (eVTOL) aircraft, others, like electric railway, are well established. Manufacturers within each segment are working to transition from traditional mechanical solutions to electrified systems that can increase power, improve efficiency, and reduce carbon dioxide (CO₂) emissions from transportation.

The ratio of vehicle electrification is growing across all transportation segments. Currently, 19% of EVs, more than 10% of construction and agriculture vehicles, 1 to 2% of water vehicles, and 45% of aircraft are fully and partially electrified. These segments are growing at CAGRs of 20% for EVs, 21.5% for construction and agriculture vehicles, 12.7% for water vehicles, and 13% for aircraft from about 2023 to 2030.

 

Figure 1. Examples of industrial e-mobility applications within land, sky, water, and railway markets. Image used courtesy of Bodo’s Power Systems [PDF]

 

Factors Driving Industrial E-Mobility

Two driving factors have prompted the rapid and widespread shift to vehicle electrification.

 

Global Targets for Emissions Reduction

Transportation accounts for 20% of global carbon dioxide emissions, producing approximately 7.6 GtCO₂ annually. This is primarily due to diesel and gasoline burning within internal combustion engine (ICE) vehicles. Although passenger cars and vans are the leading source of emissions, freight, shipping, aviation, and railway all contribute to the total environmental impact.

Therefore, governments worldwide are implementing increasingly stricter regulations (and offering new incentives) to curb emissions and accelerate the production of sustainable transportation. These regulations focus on reducing greenhouse gas emissions within given transportation segments. For example, the EPA Cleaner Trucks Initiative in the United States, PE-CONS 60/19 in the European Union, and VI Fuel Standards in China all set CO2 emissions performance standards for new light- and heavy-duty construction and agriculture vehicles.

Further, the International Maritime Organization has implemented regulations to reduce greenhouse gas emissions from ships, including the Marine Environment Protection Committee (MEPC 80) session that targets a 40% reduction in CO2 emissions from international shipping. The Energy Efficiency Design Index requires a maximum energy efficiency level for different ship types and size segments. This equates to a 30% CO2 reduction level for new builds in 2025 compared to the 2000-2010 average. Other organizations, including the International Civil Aviation Organization, the European Union Aviation Safety Agency, the Federal Aviation Administration, and the Civil Aviation Administration of China, all set emissions standards for aircraft.

To reduce emissions and adhere to regulations, industrial e-mobility markets depend on the benefits of electrification: energy efficiency and zero emissions.

 

Innovations in Power Semiconductors

Industrial e-mobility applications require reliable and efficient solutions to manage high voltages and currents under demanding environmental conditions. Compared to silicon, silicon carbide devices enable higher switching frequencies and greater power densities at much higher operating temperatures—all necessary for high-power industrial e-mobility applications.

Wolfspeed’s release of automotive-qualified (AEC-Q101) silicon carbide MOSFETs enabled manufacturers to transition from ICE to electric vehicles. In 2019, the release of higher-power silicon carbide power modules, including the XM3 product family from Wolfspeed, enabled DC fast chargers to achieve a full charge in less than 4 minutes, making EV adoption more appealing and affordable for consumers. Automotive OEMs like General Motors, Lucid Motors, Jaguar Land Rover, Mercedes, and others continue to announce significant electrification plans for next-generation EVs (including the transition from 400 V to 800 V power distribution architectures). State-of-the-art industrial e-mobility applications are following closely behind these developments, relying on technological innovations in silicon carbide to provide higher power density, higher system efficiency, and longer range, along with lower system cost and long-term reliability.

 

Table 1. Wolfspeed XM3 silicon carbide power module family.

Product SKU	Configuration	Blocking Voltage	Current Rating	RDS(ON) at 25°C	Maximum Junction Temperature	Qualification
CAB320M17XM3	Half-Bridge	1700 V	320 A	3.5 mΩ	175 °C	Industrial
CAB400M12XM3	Half-Bridge	1200 V	400 A	4 mΩ	175 °C	Industrial
CAB425M12XM3	Half-Bridge	1200 V	425 A	3.2 mΩ	175 °C	Industrial
CAB450M12XM3	Half-Bridge	1200 V	450 A	2.6 mΩ	175 °C	Industrial
EAB450M12XM3	Half-Bridge	1200 V	450 A	2.6 mΩ	175 °C	Automotive

 

Industrial E-Mobility Case Study: Electric Water Vehicles

Let’s take a closer look at how the benefits of silicon carbide can enable new developments in electric water vehicles, ranging from jet skis and yachts to passenger ferries, water taxis, harbor craft, cargo ships, tankers, and submarines.

 

Half-Bridge Power Module Designed to Enable High Power Density

Wolfspeed developed the XM3 power module platform to maximize the benefits of silicon carbide while keeping the module and system design robust, simple, and cost-effective. With half the weight and volume of a standard 62 mm module, the XM3 power module maximizes power density while minimizing loop inductance and enabling simple power bussing. The optimized packaging enables 175°C continuous junction operation with a high-reliability silicon nitride (Si3N4) power substrate to ensure mechanical robustness under extreme conditions. The XM3 fits demanding applications such as industrial e-mobility main inverters.

Within the main inverter of a water vehicle, XM3 power modules enable significant system-level optimization. Design engineers can increase power density without increasing system size by moving from a 200 kW powered by the CAB400M12XM3 to 300 kW powered by the CAB450M12XM3 inverter.

We used a 200 kW three-phase inverter reference design to compare silicon carbide power modules to silicon IGBTs.

 

Table 2. Comparing a 200 kW to 300 kW silicon carbide inverter.

	Wolfspeed SiC 200 kW inverter CRD200DA12E-XM3	Wolfspeed SiC 300 kW inverter CRD300DA12E-XM3
Weight	6.2 kg	6.2 kg
Volumetric power density	21.7 kW/liter	32.25 kW/liter
Efficiency	98.28%	98.3%

 

This inverter design features a complete stack-up, including modules, cooling, bussing, gate drivers, voltage/current sensors, and controllers. It can be used with Wolfspeed’s SpeedFit Design Simulator tool and Power Applications Forum.

Overall, silicon carbide enables higher power, greater efficiency, lower switching losses, and higher switching frequency within a lighter-weight, smaller system.

 

The Electrification of Everything Inside Industrial E-Mobility

In addition to main inverters for battery electric vehicles (BEVs) and fuel cell inverters for fuel cell electric vehicles (FCEVs), industrial e-mobility applications can integrate power electronics within battery management systems (BMS), auxiliary power supplies, auxiliary power drives, pump and fan actuators (HVAC systems), and onboard chargers. Each electrified system further reduces the number of mechanical components compared to ICE vehicles, enabling greater efficiency, lighter weight, and lower total cost of ownership.

 

Figure 2. Wolfspeed XM3 silicon carbide power module. Image used courtesy of Bodo’s Power Systems [PDF]

 

Figure 3. Wolfspeed 200 kW XM3 three-phase inverter. Image used courtesy of Bodo’s Power Systems [PDF]

 

These electrified systems conserve system-wide energy usage, reduce emissions, and extend lifetime through low losses, high power density, and high reliability and robustness. However, the operating environments of industrial e-mobility applications, including temperature fluctuations, vibration, high humidity, and harsh climates, impact which systems benefit most from electrification.

For example, water vehicles may integrate electric elevators, cranes, anchor winches, and automation systems in addition to the main inverter.

 

Image used courtesy of Bodo’s Power Systems [PDF]

Figure 4. Comparing the simulated efficiency and switching losses between a Wolfspeed silicon carbide 200 kW power module [CAB400M12XM3] and a silicon 200 kW IGBT for a water vehicle 800 V main inverter. Image used courtesy of Bodo’s Power Systems [PDF]

 

Figure 5. Power electronics systems within industrial e-mobility applications. Image used courtesy of Bodo’s Power Systems [PDF]

 

Figure 6. Example power electronics systems within water vehicles that can benefit from silicon carbide devices. Image used courtesy of Bodo’s Power Systems [PDF]

 

Numerous systems can also be electrified within off-highway land vehicles, which range from small forklifts to megawatt-consuming mining trucks. For example, electrical power take-off (ePTO) drives can lessen the load on the main inverter within heavy-duty construction and agriculture vehicles by harnessing and distributing power to auxiliary functions. Lower-power inverters can replace mechanically driven systems such as fans, pumps, actuators (HVAC), and thermal management systems.

Advanced air mobility applications can integrate smaller, more efficient electronic systems that can lower weight and conserve space inside vehicles where size, weight, and power (SWaP) ratios matter most. Electric spoiler controls, solid-state power controllers, circuit breakers, de-icing systems, and green taxing systems are key systems within these vehicles. The lighter weight and smaller size achieved by integrating power electronics within these auxiliary systems translate into extra range and cargo capacity.

Finally, regional, metro, and high-speed railway applications operate at high voltages, sourcing power distributed from a grid to overhead (or under rail) lines. Trains can also incorporate electric power systems for door control, braking, and energy recuperation within battery and grid designs. Each system requires reliable and efficient power semiconductors to supply and manage electrical switching. Silicon carbide is the best-in-class technology for the voltage classes required by the main inverter and the wide range of auxiliary power supplies and drives essential within industrial e-mobility applications.

In addition to a larger quantity of batteries, industrial e-mobility will require more powerful batteries to get the necessary energy density within the same space (more watt-hours per kilogram). Batteries with higher power density are better suited to vehicles with higher power inverters, such as heavy-duty construction vehicles and cargo ships. These battery and hydrogen market developments are essential to the future of industrial e-mobility.

Infrastructure—high power charging stations, electric grid capacity, and hydrogen refueling stations—is also crucial.

Regional and local governments are investing in charging stations to boost EV adoption, but expanding, scaling, and maintaining efficient, fast, and high-power charging infrastructure is a substantial undertaking. For EVs, this means roadside superchargers.

 

Figure 7. Renewable energy sources can support upcoming high-power charging infrastructure at vertiports and harbors. Image used courtesy of Bodo’s Power Systems [PDF]

 

For long-haul trucks, this means megawatt charging system (MCS) technology. For regional buses, this means depot charging. For ships, this means charging at harbor ports. For aircraft, this means charging at vertiports.

 

Wolfspeed’s Long-Term Vision

Wolfspeed is leading the transition from silicon to silicon carbide as we enable the industry through a growing number of product portfolios that scale from less than 2 kW up through the megawatt range and address a broad range of voltage, current, and isolation requirements.

 

Figure 8. Wolfspeed’s innovations in silicon carbide materials and devices have enabled many different markets, including advancements in industrial e-mobility. Image used courtesy of Bodo’s Power Systems [PDF]

 

From now until 2027, we expect a significant percentage of the silicon carbide device market to come from industrial and energy applications, including industrial e-mobility.

For more than 35 years, Wolfspeed has focused on producing vertically integrated silicon carbide wafers and high-quality power devices in our mission to save the world energy. Wolfspeed has manufactured more than 60% of the world’s silicon carbide. Our silicon carbide devices have surpassed 12 trillion field hours. We have a global footprint of support. We can work directly with manufacturers to develop high-performance silicon carbide products optimized for the specific requirements of industrial e-mobility applications.

Wolfspeed is scaling its capacity to meet the surge in demand for reliable and efficient energy conversion and power delivery solutions. In 2022, we opened the world’s first and largest 200 mm silicon carbide fabrication facility in Marcy, New York. This state-of-the-art power wafer fab will be automotive-qualified and has already started shipping MOSFETS. It is complemented by our materials factory expansion at our Durham, North Carolina headquarters, our upcoming materials manufacturing facility in Siler City, North Carolina, and the world’s most advanced silicon carbide device manufacturing facility planned for Saarland, Germany. These investments are necessary to support the rapid growth of industrial e-mobility applications, meet the climate goals of nations around the world, and achieve sustainable electrification.

 

This article originally appeared in Bodo’s Power Systems [PDF] magazine.