BMW ActiveHybrid technology has been developed specifically for use in a particularly dynamic vehicle in this segment and for a broad range of practical use going far beyond city traffic as such. The big advantage, therefore, is the overall optimisation of drivetrain efficiency in all speed ranges and under all conditions.
The two-mode active transmission is based on an ECVT (electric continuously variable transmission) operating in two separate modes. One mode is for setting off with particular power and for driving at low speeds, the second is for motoring at high speeds.
BMW ActiveHybrid X6
When setting off only one of the two electric motors is activated. Then, as soon as the driver requires more power, the second electric motor automatically activates the combustion engine and subsequently serves as a generator providing a permanent supply of electric power.
When driving steadily at a higher speed most of the power required is delivered by the combustion engine in a largely mechanical process. Here again, one of the two electric motors acts as a generator.
Together with the mechanical components, the electric motors form a joint transmission unit providing the optimum transmission ratio at all times as a function of driving conditions. The mechanical link within the two-mode active transmission is provided by three planetary gearsets in a configuration dividing the drive power generated by the combustion engine and the two electric motors into two transmission modes and therefore ensuring a degree of variability in combining the two power sources conventional hybrid drive would not be able to provide.