Renault S.a.s.

Clement Nouvel

Andre Agneray

Xavier Jaffrezic

Julien Couillaud

Paulo Barroso

Christophe Ripoll

Nabil Meziti

Paulo Barrosso

A voltage pulse train generator which may find application to control of an ultrasound piezoelectric injector, and including a voltage source providing a DC initial voltage, a DC/DC converter supplied with the initial voltage and configured to charge a capacitor according to an intermediate DC voltage greater than the initial voltage, a DC/AC converter operating by switching, by alternating active phases and inactive phases, which is configured to transform the intermediate voltage from the capacitor into a final voltage pulse train, and a control unit provided for driving the converters. The DC/DC converter is configured to operate to charge the capacitor at a same time as the DC/AC converter, at most during the inactive phases of the switching of the DC/AC converter.

Voltage pulse train generator, application to the control of an ultrasound piezoelectric injector

A plasma generating device including: a supply circuit including a switch controlled by a control signal for applying an intermediate voltage on an output of the control circuit at a frequency defined by the control signal; a plurality of plasma-generating plug coils arranged in parallel on the output via connectors, each connector being adapted to be removably connected to a corresponding plug coil and including a mechanism adapted to offset the resonance frequency of the plug coil so that each plug coil has a distinct resonance frequency; a control device of the supply circuit, that determines the control frequency from the resonance frequencies of the plug coils to selectively control the plug coils according to the control frequency used.

Control of a plurality of plug coils via a single power stage

A radiofrequency plasma generating device including: a supply circuit including a switch controlled by a control signal for applying a voltage on an output of the control circuit at a control frequency; at least two plasma-generating circuits connected in parallel at the output of the supply circuits, each circuit having its own resonance frequency and being capable of generating plasma when a high voltage level is applied to the output of the supply circuit at a frequency substantially equal to the resonance frequency of the plasma generation circuit; and a supply control device determining the control frequency from the resonance frequencies of the plasma generation circuits to selectively control each circuit according to the control frequency used.

A high-voltage generator device, including an inductive-capacitive resonator capable of producing a high voltage, a mechanism generating a high-frequency control pulse train, a voltage source, a capacitor, and a voltage generator including a switching transistor, the control electrode of which is connected to the output of the mechanism generating the high-frequency control pulse train, the source of the switching transistor being connect to ground, and the drain of the switching transistor being capable of delivering a voltage pulse train to the inductive-capacitive resonator in response to the control pulse train received on the control electrode of the switching transistor. The drain of the switching transistor is connected to the inductive-capacitive resonator via an isolating transformer, the isolating transformer being connected in parallel with a capacitor, the isolating transformer also being connected to the voltage source.

High-voltage generator device

A method for controlling a radio-frequency plasma generator including a supply circuit with a switch controlled by at least one control pulse train, for applying an intermediate voltage at a control frequency on an output to which is connected a resonator for generating a spark between two electrodes when a high voltage level is applied to the output. The method receives first and second measurement signals respectively representative of the operation of a combustion engine and of the type of spark generated; and real-time adjusts, based on the received measurement signals, at least one parameter selected from at least the intermediate voltage level, the control frequency, and the duration of the control train, to promote branching of the spark generated.

Optimized generation of a radiofrequency ignition spark

A control device for an ultrasonic piezoelectric actuator including a first stage supplied by a DC voltage source and including a mechanism forming a second DC voltage above that voltage delivered by the DC voltage source, and a second stage including a mechanism amplifying the second voltage and chopping the voltage obtained by excitation of the actuator with the chopped voltage, under control of a computer. The amplifying mechanism includes an inductor in electrical resonance with the piezoelectric actuator. The inductor is connected to the first stage so as to constitute, during formation of the second voltage, a secondary winding of a transformer forming part of a flyback voltage converter introduced into the first stage to develop the second voltage. The control device may find application to control of a fuel injector in an internal combustion engine.

Control device for an ultrasonic piezoelectric actuator

A device for measuring an ionization current of a spark plug of a type with a resonant structure, including a motor vehicle ignition system, the spark plug being coupled to a generator including a regulating capacitor. The generator includes a polarizer that polarizes the spark plug, connected between the generator and the spark plug, and a device that measures ionization current of the spark plug, connected between the regulating capacitor and ground.

Method for measuring an ionization current of a spark plug of the type with resonant structure and corresponding device

A device for controlling a power supply of a radio frequency ignition of a combustion engine, including: an interface that receives measurement signals of operating parameters of a combustion engine; an interface that outputs a control signal; a module that stores relationships between measurement signals and the frequency of a control signal to be generated; a module that determines the frequency of a control signal to be generated on the basis of measurement signals received on the reception interface and of the relationships stored; and a module that applies the control signal at the determined frequency.

Method and device to optimize the excitation frequency of a resonator based on predetermined relationships for operating parameters of a combustion engine

A radio frequency plasma generator power supply, including: an interface that receives a request to determine an optimal control frequency; an output interface configured to be connected to a plasma generation resonator; a power supply module configured to apply a voltage at a set point frequency to the output interface, the voltage, depending on its frequency, selectively unable to allow generation of plasma of the resonator on receipt of a request during a phase optimizing power supply frequency of the generator and able to allow generation of plasma of the resonator during an operating phase; an interface that receives an electrical measurement of power supply of the resonator; a module that determines optimal control frequency, successively provides various set point frequencies to the power supply module on receipt of a request, and determines an optimal control frequency depending on electrical measurements received by the reception interface.

Optimization of the excitation frequency of a resonator

A device for driving ultrasound piezoelectric actuators, on the basis of a DC voltage. The device includes an impedance matching branch mounted in parallel with the actuators and including a capacitor in series with a selection switch, which is closed and opened, at the same time as the selection switch of the actuator to be excited, so that the voltage across the terminals of the matching capacitor and the voltage across the terminals of the selected actuator are almost zero before the start and after the end of the injection. A method of controlling the matching switch makes it possible to benefit from the capacitive charge during the pulse train causing the injection, while circumventing abrupt discharges at the start of the train. Such a device and method may find application to the engines of motor vehicles, as one example.

Device and method for driving an ultrasound piezoelectric actuator

A control device including: an input terminal for receiving a logic control signal; an output terminal for delivering an output control signal from the high-voltage MOS transistor; a first NMOS control transistor with low internal impedance, which is connected between ground and the output terminal and the gate of which is connected to the input terminal; and a second PMOS control transistor, which is connected between a supply terminal and the output terminal and the gate of which is connected to the input terminal by a bipolar transistor mounted to a common base, and which is current controlled at the emitter thereof by a capacitive connecting circuit.

Device for controlling a high-voltage transistor, in particular a MOS transistor of a high-voltage radio-frequency generator for the spark ignition of an internal combustion engine

A load measuring circuit including a cable including first and second conductors and a shielding. The conductors are connected by a first end thereof to a load, the shielding is not connected to a ground at the end, and the conductors are connected to a generator by the second end thereof. A transformer includes a first winding connected to a conductor on the second end of the cable, a second winding is connected between a ground and the shielding on the second end of the cable, and a third winding is connected to a current measuring member.

Growing community of inventors

Verneuil sur Seine, France

Clement Nouvel