In Plant Landshut, where some of the most advanced electrical components of the BMW are developed, we visited a workshop that provided an inside view of the electrical drive train of the new class. Fresh discussions about BMWS battery technology of the sixth generation (Gen6) and our attention turned to the second half of the equation: the electric motors that are responsible for the performance of the sidewalk.
While the battery amplifiers often dominate the EV discussions, engines and power electronics are just as crucial for the definition of how an electric car works, how efficiently it uses energy, and – especially for BMW – how it drives. And not surprisingly, the company does not pursue the industry play book.
More performance, more flexibility
In contrast to many car manufacturers that rely exclusively on permanent magnetic synchronous engines (PSM) – the rare earth materials use – BMW changes a different approach and combines externally stimulated synchronous motors (EESM) on the rear axle and asynchronous motors (ASM).
The Gen5 Electric Drive system from BMW, which is used in models such as IX and I4, has matured since its introduction in 2018. However, Gen6 improves in almost every respect. One of the biggest changes? More engines, more power and a more adaptable platform.
Instead of the dual engine setups used in most of today’s performance electric vehicles, the new class platform can absorb up to four electric motors. This is a big leap in flexibility. Thanks to the refinements in their design and materials, these engines are easier, more efficient and cheaper to produce.
The BMW engineer Michael Salmansberger took a closer look at the new engines and explains that four variants of the EESM units are planned, each weighing about 125 kg (276 lbs) and between 268 hp (200 kW) and 402 hp (300 kW ) produce. . The ASM is supplied with two variants in the front axle with 120 and 180 kilowatts on the rear axle.
The potential potential is obvious BMW could be scaled from a one-engine new class limousine to a quad-motor, powerful M-car with over 1 megawatt (1341 hp) using the same basic technology. We have already seen what the BMW Vision Driving Experience Prototype can do.
There is also a change of how this force reaches the bikes. Instead of a conventional two -way gearbox, BMW uses a single transmission, but is operated as a two -stage gear thanks to an intermediate shaft that adapts the gear ratio as required. It is essentially a powerful individual fear system for both engines.
Why BMW remove from permanent magnets
Most premium EVs, including those from Tesla, Lucid and Mercedes-Benz, rely on permanent magnetic engines for their high efficiency and compact size. The catch? They require rare earth materials that are expensive, environmentally problematic and are subject to geopolitical supply chain problems.
The externally excited synchronous engine (EESM) from BMW eliminates this dependency by creating its own magnetic field using an electrically stimulated rotor instead of permanent magnets. This has some important advantages:
- No trust in rare earth materials that make procurement and production more sustainable.
- More precise control via the torque tax, since the magnetic field can be set dynamically.
- Reduced energy losses at lower loads and improves overall efficiency.
However, there is a reason why EESM engines are not common to make an electrical input to create the magnetic field, which can slightly reduce efficiency under constant high-load conditions. BMW recognizes this, however, argues that the ability to optimize the output of performance dynamically outweighs the disadvantages. By adapting the suggestion levels in the current flies, the gene6 engines from BMW can finish the efficiency based on drive conditions, which can not do permanent magnetic engines so effectively.
An intelligent front engine for efficiency
The choice of BMW to use an asynchronous motor (ASM) on the front axle is just as strategic. In contrast to synchronous motors, an ASM does not require continuous electrical input, which means that it can remain inactive if the front-wheel traction is not required. This means less energy consumption during normal driving, while at the same time an immediate commitment is made possible if additional handles or electricity is required.
While ASMS tends to be somewhat less efficient compared to permanent magnetic motors, the main advantage is that its ability to work without zero if you do not work without zero. This setup enables BMW to dynamically compensate for efficiency and XDRIVE performance instead of force all four bikes to supply electricity at any time.
The result? A system that maximizes the area of normal driving and at the same time keeps the AWD ability to stand on standby balance if it is needed.
Silicon carbide: the secret efficiency booster
Even with better engines, the power supply electronics make an EV drive train. For this reason, BMW changes to Silicium carbid (SIC) semi -semiconts (already in the revised BMW IX), which reduces the energy loss in the power conversion and:
- More efficient operation at 800 V
- Lower heat generation, smaller cooling systems and improved durability
- Faster and more precise energy management, which improves both efficiency and reactionability
BMW claims that these changes contribute to an efficiency gain of 20% in the total drive train, although the results of the real world ultimately determine how much of it leads to an improved range and performance.
Scalability: from efficiency to M performance
One of the largest snack bars from the Landshut workshop was how modular and scalable BMW -new electrical drive system is.
However, a BMW-class class class class is the most efficient setup, but for high-performance models, BMW can add additional EESM engines for more power and AWD ability. Future M-cars could use a quad engine setup that enables advanced torque vectoring, AWD handling and extreme outputs for the AWD and extreme services.
The system was interpreted from the start to enable a precise distribution of performance between the axes and individual bikes.
A different approach than the competition
BMW’s strategy differs from competitors in a few important ways.
- Tesla and Lucid continue to refine the permanent magnetic engine technology and prioritize efficiency and performance density.
- Porsche and Audi follow a hybrid approach and combine PSM and ASM engines for performance optimization.
- Mercedes-Benz remains on rare for their high efficiency and predictable performance for PSM setups on rare.
BMW relies on the fact that its rare -free approach pays off in costs, efficiency and long -term sustainability, even if it requires more extensive electricity shipping.
Engineering about hype?
Participation in BMW’s Landshut Workshop has emphasized one thing: the company does not rush to EVS just to fulfill regulations or to follow trends. It would like to use the same technically guided approach that has defined its combustion drive strands for decades. Will you climb up? We will find it out soon, but at the moment the theory sounds great.
