Abstract: An autonomous device for measuring at least one characteristic of a fluid circulating in a conduit in a flow direction comprises a permanent magnetic field source, a magneto-electric converter and a processing circuit capable of using the electric charges supplied by the converter to supply a measurement of a characteristic of its environment. The source and the converter are placed in a stator and a rotor forming the device. The autonomous device further comprises attachment means allowing the stator to be fixedly placed in the conduit or at one end of the conduit, in a configuration in which the axis of rotation of the rotor is parallel to the flow direction. A control system may employ at least one such autonomous device.

Abstract: A magneto-electric converter capable of converting a variation in magnetic field into a potential difference between two electrical terminals includes a support layer comprising two electrical terminals; a stack disposed on the support layer of a first layer made from a magnetostrictive material defining the reference plane and of a second layer made from a piezoelectric material having a polarization axis in the plane defined by the second layer, parallel to the reference plane; the second layer comprising electrodes; and a means for electrical connection of the electrodes to the electrical terminals.

Abstract: An electrical generator comprises a converter including two electrical terminals for converting a variation in a magnetic field into a potential difference between the terminals. The generator includes a stack of a first layer comprising an anisotropic magnetostrictive material defining a reference plane and a second layer comprising a piezoelectric material. The first layer has at least one preferential axis of deformation in the reference plane and the second layer has a polarization axis parallel to the reference plane, the preferential axis of deformation of the first layer being aligned to within 15° with the polarization axis of the second layer. The generator includes a source that generates the magnetic field, the strength of which is insufficient to magnetically saturate the material of the first layer. The source and converter are able to rotate with respect to each other so as to vary the orientation of the magnetic field.

Abstract: An energy harvester comprises: converter capable of converting a variation of energy to be harvested into a potential difference between two electric terminals by accumulating charges; the converter including a stack of layers with at least one first layer made of a piezoelectric material; a collection circuit connected to the terminals and comprising a switch, the collection circuit being configured to harvest the charges when the switch is in a closed state; the converter being able to emit acoustic vibrations in an audible frequency band when the collection circuit harvests the charges; the energy harvester further comprises a control circuit configured to control a plurality of closing-opening sequences (SFO) of the switch, when the potential difference reaches a defined threshold, so as to harvest the charges through a plurality of partial discharges of the converter and to limit the stress deviation experienced by the first layer during each discharge.

Abstract: An autonomous device for measuring at least one characteristic of a fluid circulating in a conduit in a flow direction comprises a permanent magnetic field source, a magneto-electric converter and a processing circuit capable of using the electric charges supplied by the converter to supply a measurement of a characteristic of its environment. The source and the converter are placed in a stator and a rotor forming the device. The autonomous device further comprises attachment means allowing the stator to be fixedly placed in the conduit or at one end of the conduit, in a configuration in which the axis of rotation of the rotor is parallel to the flow direction. A control system may employ at least one such autonomous device.

Abstract: A generator for transforming a translational movement of a push element into an accumulation of electric charges comprises a converter capable of transforming a magnetic field variation into a charge accumulation, and a magnetic field source defining a housing in which a magnetic field prevails. The push element is movable from a first position to a second position along a translational direction. According to a first aspect, the generator comprises a transmission device for transmitting the movement of the push element into a rotational movement of the field source or of the converter in order to vary the magnetic field in the reference plane of the converter. According to another aspect, the push element is moved from a first position in which the converter is subject to a first field configuration, to a second position in which the converter is subject to a second field configuration, different from the first.

Abstract: A magneto-electric converter capable of converting a variation in magnetic field into a potential difference between two electrical terminals includes a support layer comprising two electrical terminals; a stack disposed on the support layer of a first layer made from a magnetostrictive material defining the reference plane and of a second layer made from a piezoelectric material having a polarization axis in the plane defined by the second layer, parallel to the reference plane; the second layer comprising electrodes; and a means for electrical connection of the electrodes to the electrical terminals.

Abstract: An electrical generator comprises a converter including two electrical terminals for converting a variation in a magnetic field into a potential difference between the terminals. The generator includes a stack of a first layer comprising an anisotropic magnetostrictive material defining a reference plane and a second layer comprising a piezoelectric material. The first layer has at least one preferential axis of deformation in the reference plane and the second layer has a polarization axis parallel to the reference plane, the preferential axis of deformation of the first layer being aligned to within 15° with the polarization axis of the second layer. The generator includes a source that generates the magnetic field, the strength of which is insufficient to magnetically saturate the material of the first layer. The source and converter are able to rotate with respect to each other so as to vary the orientation of the magnetic field.

Abstract: A power generator including a converter with an electromechnical transducer and a magnetostrictive layer to convert a variation of a magnetic field into a mechanical deformation exerted on the transducer. There is a magnetic field source including a group of several permanent magnets. One of the group or the converter is movable, between first and second positions. The group has several first permanent magnets, one having an aspect ratio of between 1/10 and ten and most of the field lines that loop back do not pass through another first permanent magnet. The first permanent magnets are arranged such that the magnetic field induced inside the magnetostrictive material in the first position by one of the first permanent magnets is parallel to and in the direction opposite to the magnetic field induced at the same instant in the magnetostrictive material by the next first permanent.

Abstract: An energy harvester having a converter suitable for converting a variation of the energy to be harvested into a corresponding excess of electrical charges. There is a circuit for collecting the excess of electrical charges, the circuit is equipped with a controllable switch and a control device for the switch designed to control the switching of this switch to its closed position. The control device is suitable for exerting a force which stresses the electrical contacts towards one another. The force varies continually as a function of the quantity of electrical charges present on the first terminal and bringing the electrical contacts to bear on one another only when the excess of electrical charges exceeds a predetermined threshold, and/or for ionizing the electrically insulating medium to produce an electrical arc between the two electrical contacts only when the excess of electrical charges exceeds the predetermined threshold.

Abstract: A power generator including a converter with an electromechnical transducer and a magnetostrictive layer to convert a variation of a magnetic field into a mechanical deformation exerted on the transducer. There is a magnetic field source including a group of several permanent magnets. One of the group or the converter is movable, between first and second positions. The group has several first permanent magnets, one having an aspect ratio of between 1/10 and ten and most of the field lines that loop back do not pass through another first permanent magnet. The first permanent magnets are arranged such that the magnetic field induced inside the magnetostrictive material in the first position by one of the first permanent magnets is parallel to and in the direction opposite to the magnetic field induced at the same instant in the magnetostrictive material by the next first permanent.

Abstract: An energy harvester having a converter suitable for converting a variation of the energy to be harvested into a corresponding excess of electrical charges. There is a circuit for collecting the excess of electrical charges, the circuit is equipped with a controllable switch and a control device for the switch designed to control the switching of this switch to its closed position. The control device is suitable for exerting a force which stresses the electrical contacts towards one another. The force varies continually as a function of the quantity of electrical charges present on the first terminal and bringing the electrical contacts to bear on one another only when the excess of electrical charges exceeds a predetermined threshold, and/or for ionizing the electrically insulating medium to produce an electrical arc between the two electrical contacts only when the excess of electrical charges exceeds the predetermined threshold.