Autonomous device for measuring the characteristics of a fluid circulating in a conduit and system for controlling ventilation, air conditioning and/or heating using such a device

An autonomous device for measuring at least one characteristic of a fluid circulating in a conduit in a flow direction, the autonomous device comprising:

• a rotor comprising a turbine capable of being driven in rotation by the fluid, the rotor being assembled to a stator, the turbine comprising a hub and a plurality of blades attached to the hub;
• an attachment feature allowing the stator to be fixedly placed in the conduit or at one end of the conduit, in a configuration in which an axis of rotation of the turbine is parallel to the flow direction;
• a permanent magnetic field source defining a magnetic plane perpendicular to the axis of rotation of the turbine;
• a magneto-electric converter having a reference plane and capable of transforming a variation in the reference plane of a magnetic field into a mechanical deformation capable of generating electric charges;
• a processing circuit, electrically connected to the magneto-electric converter, and configured to employ the electric charges to acquire a measurement of a characteristic of an environment in which the autonomous device is located;
• and
• a device for modifying the flow of fluid circulating in the conduit by modifying the passage cross-section of the conduit, the device comprising flaps or a curtain, opening of the flaps or the curtain providing a fluid circulation passage bypassing the blades of the turbine to limit the rotational speed of the rotor;
• and
• wherein one of the magneto-electric converter and the permanent magnetic field source is included in the stator, and the other one is included in the rotor, and the stator is connected to the rotor so that the reference plane of the magneto-electric converter resides in the magnetic plane generated by the permanent magnetic field source.