Lucid Motors' electric powertrain is a true engineering marvel, showcasing the company's commitment to innovation and system-level optimization. From the compact, high-power density motor to the modular, scalable design, Lucid has pushed the boundaries of what's possible in electric vehicle powertrains which was recently showcased in an in-depth video interview with Munro Live.
Lucid's SVP of Product and Chief Engineer Eric Bach, as well as VP of Powertrain Emad Dlala, provided a deep dive into the engineering and design behind Lucid's electric powertrain. Their insights reveal key technologies and innovations that make Lucid's powertrain a standout in the industry.
Compact, Efficient Motor Design
One of the most impressive aspects of Lucid's electric powertrain is the sheer power density and compact packaging of the motor. As Emad Dlala explained, Lucid's engineers took a "clean sheet" approach to designing the motor, rethinking every component to maximize performance and efficiency.
Stator Design with Integrated Cooling
The stator, which houses the windings that generate the magnetic field to spin the rotor, features a unique design with additional slots and channels. These channels create an integrated oil cooling system, allowing the stator windings to be directly cooled. This innovative cooling approach helps extract heat efficiently from the high-power density motor.
"The idea of these channels, the top one are creating a cooling manifold in the middle and this is invented by both electromagnetic computation of fluid dynamics, thermal team myself and the team working together side by side how we could basically allow the oil...to be uniformly cooling the middle of the stator."
- Emad Dlala, VP of Powertrain, Lucid Motors
Continuous Wave Winding
Another key innovation in Lucid's motor design is the use of a continuous wave winding pattern for the stator coils. Rather than the more common bar winding approach with numerous welds, Lucid's continuous wave winding allows the wire to flow in a continuous, wave-like pattern.
This approach provides several benefits:
- Eliminates the need for 192 welds on the end turns, resulting in a more compact package
- Allows for higher slot fill with square copper wire, improving efficiency
- Enables a fully automated winding and insertion process for scalable manufacturing
As Eric Bach explained, Lucid's team recognized the potential of continuous wave winding technology, which is commonly used in alternators, and adapted it for use in their high-performance electric motor.
"We took that approach, we took it to heart, we saw it fundamentally, you know, better in almost every aspect basically and we worked with the manufacturing team to make it happen."
- Eric Bach, SVP of Product and Chief Engineer, Lucid Motors
Integrated Differential and Gearing
Lucid has also innovated on the gearing and differential system for their electric powertrain. Rather than a traditional standalone differential, Lucid has integrated a high-speed, low-torque differential directly into the rotor shaft.
This compact packaging solution allowed Lucid to maximize the available space within the motor, enabling their industry-leading front trunk (frunk) volume. The planetary gear sets used in Lucid's design also contribute to high efficiency, with the loads on the gears being carefully balanced to minimize friction.
"We optimize the electromag[netic] system around that of the rotor and the biggest also problem to solve one of the biggest also the lubrication of that system how you lubricate it...it's all one packaging problem."
- Emad Dlala, VP of Powertrain, Lucid Motors
Powertrain Modularity and Scalability
Lucid's powertrain design not only delivers impressive performance, but also provides a high degree of modularity and scalability. This modular approach allows Lucid to efficiently develop and manufacture different powertrain variants to meet the needs of various vehicle models.
Modular Inverter Design
Lucid's powertrain features a modular inverter design, with six individual inverter modules that can be easily scaled up or down depending on the power requirements. This modular approach allows Lucid to quickly adapt the powertrain for different vehicle models, such as the Lucid Air and the upcoming Lucid Gravity SUV.
"It's essentially super cheap standardized...plate stacking technology, braced. It's like every heat exchanger made the same heat exchanger technology that that's $10 that heat exchanger, but the design and the genuine, you know, innovation here is like how to make this very compact have six modules inverter with this power density in such a, you know, part."
- Emad Dlala, VP of Powertrain, Lucid Motors
Scalable Motor Configurations
Lucid has also designed their motor to be easily scalable, with the ability to configure it with different winding configurations. For example, the Lucid Air can be equipped with either a single motor or a dual motor setup, depending on the performance requirements of the specific model.
This modular approach not only simplifies Lucid's manufacturing processes, but also allows the company to quickly adapt to changing market demands and customer preferences.
Powertrain Integration and System-Level Optimization
Lucid's powertrain design goes beyond just the individual components, with a strong focus on system-level integration and optimization. The team has worked to ensure that every aspect of the powertrain, from the motor to the inverter to the gearing, is carefully designed and integrated as a cohesive system.
Electromagnetic Interference (EMI) Mitigation
One example of this system-level approach is Lucid's handling of electromagnetic interference (EMI) between the motor and the resolver (position sensor). Typically, this can be a significant challenge, as the high-power, high-speed operation of the motor can induce noise and interference in the resolver.
Lucid's team, however, was able to address this issue through a combination of careful electromagnetic modeling, shielding, and resolver design optimization. This allowed them to integrate the resolver directly into the motor assembly, further contributing to the powertrain's compact packaging.
"There was a significant electromagnetic interference, you know, issue that we have to resolve and this, this if it wasn't in-house, I can tell you the reality just authentically, probably people would have given up on this. But since we have all the simulation tools to redesign the resolver in terms of how many lobes, what's the, what's the number of windings and what kind of shielding, we made it possible with just normal resolver technology, eventually just optimize for this system."
- Emad Dlala, VP of Powertrain, Lucid Motors
Thermal Management and Efficiency Optimization
Lucid's powertrain design also showcases a deep understanding of thermal management and its impact on overall system efficiency. By carefully modeling and simulating the thermal behavior of the motor, inverter, and other components, the team was able to optimize the cooling systems and minimize losses.
This includes the innovative stator cooling approach, as well as the parallel-flow cooling design for the inverter's silicon carbide power modules. The result is a highly efficient powertrain that can deliver exceptional performance without sacrificing range or reliability.
"We didn't make the world's best motor in isolation and then tried to make the world's best inverter. We made the complete system world-class by trading capabilities and attributes essentially if you wish between the two."
- Emad Dlala, VP of Powertrain, Lucid Motors
Lessons Learned and Future Scalability
Lucid's powertrain development journey has not been without its challenges, but the team has leveraged the lessons learned from the Lucid Air program to ensure a smoother launch for the upcoming Lucid Gravity SUV and future models.
Lessons Learned from Lucid Air Launch
When Lucid first started developing the Lucid Air, the company was a relatively small team of just 120 people, with only 70 of those being engineers. This meant that Lucid had to rapidly scale up its engineering and manufacturing capabilities while simultaneously launching a highly innovative vehicle.
As Eric Bach explained, this rapid growth and learning process led to some initial quality issues that the team had to address. However, the team meticulously documented these lessons and used them to improve the design and manufacturing processes for the Lucid Gravity.
"We learned a lot of lessons while launching Air and that was not necessarily because we were not capable of doing it right, but you if you remember, we were a very small and different company when we started developing Air."
- Eric Bach, SVP of Product and Chief Engineer, Lucid Motors
Scalability and Future Platforms
With the lessons learned from the Lucid Air launch, the team is now well-positioned to scale up production and develop future vehicle platforms. The Lucid Gravity, for example, will benefit from the existing manufacturing infrastructure and a more experienced team.
Looking ahead, Lucid is also developing a midsize platform that will leverage the powertrain and platform technologies refined through the Lucid Air and Gravity programs. This midsize platform is intended to bring Lucid's efficient and high-performance powertrain to a broader market, helping the company achieve its goal of producing up to 1 million vehicles per year.
"We are aspiring to become a company with maybe a million vehicles per year and then a big portion of that million will come from this midsize platform. We can put multiple top hats on that platform, it's going to get the next generation of power trains."
- Eric Bach, SVP of Product and Chief Engineer, Lucid Motors