A control method for controlling a centrifugal fan for ventilating a person, comprising at least one of the steps of:
- controlling the centrifugal fan using a first control loop, by means of which the ventilation pressure at an outlet opening of the centrifugal fan can be adjusted to an inhalation pressure or an exhalation pressure which is equal to or less than the inhalation pressure, and
- controlling the centrifugal fan using a second control loop, by means of which at least one of the following can be adjusted:
- a frequency of inhalation phases, in which the inhalation pressure is established at the outlet opening of the centrifugal fan, and a duty cycle of a duration of the inhalation phases relative to a duration of exhalation phases, in which the exhalation pressure is established at the outlet opening of the centrifugal fan;
- wherein the centrifugal fan includes an inlet opening and an outlet opening, the centrifugal fan being adapted to receive ventilation air at the inlet opening and to provide the ventilation air at an adjustable ventilation pressure at the outlet opening, and the centrifugal fan is included in a ventilation apparatus comprising:
- a first respiration line having a first end connected to the inlet opening of the centrifugal fan, and having a second end arranged for receiving inhalation air,
- a second respiration line having a first end connected to the outlet opening of the centrifugal fan, and having a second end adapted for coupling a ventilation mask, the second respiration line being provided with a sensor device, by means of which at least one flow parameter in the second respiration line can be measured, and
- a control device adapted for controlling the centrifugal fan in dependency on at least one output signal of the sensor device, wherein
- the centrifugal fan and the second respiration line form a continuous bidirectional flow path, the adjustable ventilation pressure at the outlet opening of the centrifugal fan comprising an inhalation pressure or an exhalation pressure which is equal to or less than the inhalation pressure, and
- the first respiration line includes a valve device arranged between the inlet opening of the centrifugal fan and the second end of the first respiration line and arranged as an expiration exit for the outlet of exhalation air;
- the second respiration line is provided with a filter device which is arranged for air flow filtering;
- wherein the control device is adapted for controlling the centrifugal fan using a second control loop, by means of which at least one of the following can be adjusted:
- a frequency of inhalation phases, in which the inhalation pressure is established at the outlet opening of the centrifugal fan, and a duty cycle of the duration of the inhalation phases relative to the duration of exhalation phases, in which the exhalation pressure is established at the outlet opening of the centrifugal fan;
- wherein the control device is adapted for controlling the centrifugal fan using a third control loop, by means of which target variables of the second control circuit are adjustable in such a way that at least one of the parameters of tidal volume and minute volume of the ventilation can be matched to predetermined volume reference variables of the tidal volume or of the minute volume;
- and
- wherein the control device is adapted for controlling the centrifugal fan in dependency on an output signal of an oxygen saturation sensor using a fourth control loop, by means of which a target variable of the third control loop is adjustable such that an oxygen saturation in the blood of the ventilated person is matched to a predetermined oxygen saturation reference variable.