Method of operating an active suspension

A method of operating a plurality of active suspensions of a motor vehicle, with the active suspensions being arranged respectively between a wheel of plural wheels and a body of the motor vehicle, said method comprising:

• adding power to at least one active control element of each of the active suspension for damping a movement of the motor vehicle in a vertical direction when negotiating a terrain to thereby influence a control variable of the suspension, wherein the control variable of the active suspension is a path traveled in the vertical direction or the control variable of the active suspension is a force acting in the vertical direction;
• determining a first signal of a velocity of the body in the vertical direction and a second signal of the control variable;
• determining a value for a mechanical energy derived from the second signal;
• comparing the mechanical energy with a predefined threshold value for the mechanical energy,
• determining a phase shift between the first and second signals;
• comparing a value of the phase shift with a predefined threshold value;
• identifying a presence of excitation of the vertical body movement when the value of the phase shift deviates from the predefined threshold value at least by a tolerance value or when the value of the phase shift is greater than the predefined threshold value so that an excitation index has the value one.