MK 100^® ESC Hybrid – system layout

ESC Hybrid is based on a standard hydraulic brake system. The only additional part needed is a brake pedal position sensor. When the driver depresses the brake pedal, the driver activates the hydraulic brake. Simultaneously, the pedal position sensor measures the brake pedal stroke. The brake HECU converts the brake pedal stroke into a deceleration torque and commands an electric generator to achieve the torque.

In essence, the driver simultaneously activates the conventional hydraulic brake and the electric generator based brake. The recuperation focuses on the dominant vehicle deceleration range (up to 0.2g – dependent on the availability of the generator). The driver compensates the decreasing generator torque at low vehicle speed.

To increase the recuperation efficiency, the hydraulic brake is activated only when there is a strong brake pedal thrust, whereas with normal braking the braking energy is recuperated by the genrator (i.e. the eGap). The eGap takes advantage of the already existing valves in the brake HECU.