EP3556006A1 - Piezoelectric actuator type control device for capacitive loads - Google Patents
Piezoelectric actuator type control device for capacitive loadsInfo
- Publication number
- EP3556006A1 EP3556006A1 EP17822413.5A EP17822413A EP3556006A1 EP 3556006 A1 EP3556006 A1 EP 3556006A1 EP 17822413 A EP17822413 A EP 17822413A EP 3556006 A1 EP3556006 A1 EP 3556006A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- control
- voltage
- bus
- bridge
- supply
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
- 239000003990 capacitor Substances 0.000 claims abstract description 18
- 230000005284 excitation Effects 0.000 claims abstract description 11
- 238000004804 winding Methods 0.000 description 4
- 238000011144 upstream manufacturing Methods 0.000 description 3
- 239000000919 ceramic Substances 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 230000003042 antagnostic effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008033 biological extinction Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M11/00—Power conversion systems not covered by the preceding groups
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
- H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
- H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
- H02N2/02—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing linear motion, e.g. actuators; Linear positioners ; Linear motors
- H02N2/06—Drive circuits; Control arrangements or methods
- H02N2/065—Large signal circuits, e.g. final stages
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/80—Constructional details
- H10N30/802—Circuitry or processes for operating piezoelectric or electrostrictive devices not otherwise provided for, e.g. drive circuits
Definitions
- the present invention relates to a device for controlling at least one piezoelectric actuator driven electronically from a control computer.
- these actuators can be used to generate, on the contrary, a vibration intended to have specific characteristics in terms of amplitude, frequency, shape.
- piezoelectric actuators lie in their extreme stiffness, intrinsic accuracy and very high power density compared to other actuation principles.
- a piezoelectric actuator must be preloaded with a force that must exceed the maximum tensile force to which it could be subjected (including inertia force). This prevents tensile stress.
- An elastic prestressing device is generally used comprising a spring for preloading the piezoelectric actuator.
- a solution which consists in putting two identical actuators mounted face to face and making them work in opposition, after the application of a precharge made by rigid means.
- a second actuator shaped and arranged to generate forces that are in phase and opposite direction to the vibration-generating forces of the first actuator.
- this counter-force is generated by a second actuator which is identical to the first and which is arranged both opposite and in opposition to the latter.
- This type of assembly has the advantage of a stiffness independent of the preloading springs, and a loss of amplitude almost zero, the force seen by each actuator being very little variable.
- the arm of the inverter can thus oscillate around the level of Umax / 2, with an amplitude of Umax / 2.
- these actuators are conventionally constituted by a stack of thin layers of piezoelectric ceramics which bend under the action of an electric field, we must avoid too rapid changes in the supply voltage because the shock waves which are thus caused, propagate in the layers of the actuator and weaken its structure.
- the power electronics for controlling the actuators is generally designed to generate, from a DC voltage source, a periodic voltage, over a 0-Umax voltage swing range (with Umax varying from about 150-200V for so-called “low voltage” actuators at about 1000V for so-called “high voltage” actuators), of high frequency, up to about ten kilohertz (depending on the actuator and its environment), to excite the piezoelectric cells.
- a DC voltage source a periodic voltage
- Umax varying from about 150-200V for so-called “low voltage” actuators at about 1000V for so-called “high voltage” actuators
- Umax varying from about 150-200V for so-called “low voltage” actuators at about 1000V for so-called “high voltage” actuators
- Umax varying from about 150-200V for so-called “low voltage” actuators at about 1000V for so-called “high voltage” actuators
- high frequency up to about ten kilohertz
- the inverters based on the half-bridge topology which are widely preferred because of their simplicity of implementation and implementation, do not allow, with single-level DC voltage stages, to generate negative voltages. In other words, half-bridge inverters do not make it possible to exploit the possibility of excitation of these actuators by negative voltages.
- a full bridge inverter topology is necessary to be able to drive an actuator in all its range. of excursion, ranging from a negative voltage to a positive voltage, for example ranging from -20% Umax to 100% Umax.
- An object of the invention is to overcome this limitation.
- a device for controlling at least one piezoelectric actuator driven electronically from a control computer comprising a first DC voltage generation stage comprising a first DC converter circuit.
- said device being characterized in that said second the voltage converter circuit comprises two half-bridge switches connected in parallel across a bus capacitor connected to the first power supply line and to the second supply line of said DC supply bus; control being adapted to control each of the two half-switch bridges on the one hand, independently, in a first control configuration in which the two switch half-bridges are independently controlled to provide a respective excitation voltage ranging from zero to
- said control computer is adapted to control, in said first control configuration, a pair of piezoelectric actuators connected in a face-to-face mounting at the output of each independently controlled half-switch bridge.
- each piezoelectric actuator of a pair being connected respectively between the mid-point of said corresponding switch bridge and the first supply line of said DC supply bus and the midpoint of said corresponding switch bridge and the second line of supplying said continuous supply bus.
- said control computer is adapted to control, in said first control configuration, a single piezoelectric actuator connected at the output of each independently controlled half-switch bridge, said piezoelectric actuator being connected between the mid-point of said corresponding switch bridge and the second supply line of said DC supply bus.
- said first voltage converter circuit is adapted to be controlled by a control signal transmitted by the control computer so as to ensure a limited slope voltage rise of said DC supply bus between zero. and said positive maximum value when energizing the actuators to be driven.
- said control computer is adapted to control the two half-switch bridges in a third control configuration in which an actuator is connected between, on the one hand, the output of one of the two half-switches. switch bridges connected to the first or second supply line of said DC power bus and, on the other hand, the two mid-points, connected together, of the two half-bridge switches.
- a discharge resistor of said bus capacitor is connected in parallel with said bus capacitor between said first and second supply lines of the DC supply bus and a controllable switch is connected in series with said discharge resistor between said first and second supply lines.
- second power supply line of the DC supply bus said switch being adapted to be controlled by said control computer so as to bring the voltage of the DC supply bus back to zero after use of the actuator (s).
- an inductor is mounted at the output of the respective midpoints of the two half-bridge switches, said inductance being dimensioned so as to constitute, together with the capabilities of the actuator (s) controlled, a filter whose cutoff frequency will be less than a resonant frequency to avoid.
- the control device of the invention comprises a DC / AC voltage converter circuit 10 adapted to drive one or more actuators according to different possible modes of operation which will be detailed later.
- the DC / AC converter circuit 10 is designed to generate a periodic high voltage, which can go to several hundred volts, for example equal to 1000V, and at high frequency, which can range, for example, up to a few tens of kHz, for to excite the piezoelectric actuator or actuators, from a DC voltage source, in this case an AC / DC voltage converter circuit 20.
- This converter circuit 20 is for example a flyback type converter, which is one of the possible topologies to achieve this function.
- transformer 21 It comprises a transformer 21 and a switching transistor Tdc in series with the primary winding of the transformer 21, while a diode 22 and an output capacitor 23 are arranged at the output of the secondary winding.
- transformer 21 The transformer 21 is powered by a diode bridge 24, connected to an external AC supply network 30. The output of the diode bridge is connected to a capacitor 25 connected across the primary winding of the transformer 21 upstream of the transistor Tdc cutting.
- the "flyback" type converter circuit 20 feeds downstream a continuous power supply bus 40 having a first power supply line 41 and a power supply. a second power supply line 42, on each of which is applied an electric potential, respectively a high electric potential H, of value Umax and a low electrical potential L.
- a bus capacitor Cdc is connected between the power supply line 41 at the potential H and the supply line 42 to the potential L of the DC supply bus, upstream of the DC / AC converter circuit 10 fed by the DC supply bus 40.
- the DC / AC converter circuit 10 consists of two half-bridge (or half-bridge) inverter circuits with pulse width modulation (PWM for "Pulse Wide Modulation"), respectively 1 1 and 12, connected to each other. in parallel at the terminals of the bus capacitor Cdc on the DC supply bus 40 and which are intended to supply, independently or jointly, an excitation voltage across one or more piezoelectric actuators connected at the output of the converter circuit 10 to from a command reference.
- PWM pulse width modulation
- This control instruction comes from a control computer 50 of the control device.
- This control computer 50 is notably responsible for managing the control command of the piezoelectric actuator or actuators connected to the output of the converter circuit 10, as well as the control of the AC / DC converter circuit 20, and is based on a microcontroller, a microprocessor, a DSP (Digital Signal Processor) processor or equivalent.
- the first inverter circuit 1 1 consists of a half-bridge of switches. It comprises a switching arm 10 connected between the first power supply line 41 and the second power supply line 42 of the DC supply bus 40 and comprises two connected switches T1 1, T12 (for example of the MOSFET type) connected to each other. in series through a said middle point PM1 of the switching arm 1 10.
- the control computer 50 is adapted to generate PWM PWM PWM_12 and PWM control output signals respectively applied to the gate of the first switch T1 1 and to the gate of FIG. first switch T12. These switches are controlled so that when one of them is closed, the other is open and vice versa.
- the second inverter circuit 12 consists of a half-bridge of switches. It comprises a switching arm 120 connected between the first power supply line 41 and the second supply line 42 of the DC supply bus 40 and comprises two controlled switches T21, T22 (for example of the MOSFET type) connected in series. through a so-called midpoint point PM2 of the switching arm 120.
- the control computer 50 is adapted to generate PWM, PWM_21 and PWM_22 type control output signals respectively applied to the gate of the first switch T21. and on the gate of the first switch T22. These switches are controlled so that when one of them is closed, the other is open and vice versa.
- an inductor L1, L2 is connected at the output of the midpoint of each half-bridge inverter circuit 1 1, 12, in order to eliminate the risk of resonance of the devices containing the piezoelectric actuators connected to the output of the inverter circuits 1 1 and 12, and / or the shocks that can be generated.
- the inductance at the output of each half-bridge inverter circuit 1 1, 12 is dimensioned so as to constitute, together with the capabilities of the actuators controlled, a filter whose cutoff frequency is lower than the resonance frequency to be avoided .
- the values of the inductances can therefore be adapted to the desired application. Other types of circuits that could play this role of filter could be used.
- the simultaneous control by the control computer 50 of the DC / AC converter circuit 10, on the one hand and the two half-bridge inverter circuits 1 1 and 12 of the DC / AC converter circuit. 10 will allow, according to a first control configuration in which the two half-bridge inverter circuits are controlled independently, to control a single actuator or a pair of actuators in face-to-face assembly by half-bridge inverter circuit 1 1 and 12, operated over a range of voltages from 0 to 100% of U ma x, and according to a second control configuration in which two half bridge inverter circuits are jointly controlled to go into full bridge topology, to control an actuator operated over a voltage range of -20% to 100% U max .
- a first use case of the first control configuration concerns the case where a piezoelectric actuator alone is connected at the output of each half-bridge inverter circuit 11, 12 controlled independently by the control computer 50.
- a piezoelectric actuator A1 is connected at the output of the first half-bridge inverter circuit 1 1 and a piezoelectric actuator A2 is connected at the output of the second half-bridge inverter circuit 12.
- the piezoelectric actuator A1 is connected between the mid-point PM1 of the half-bridge inverter circuit 1 1, downstream of the inductor L1, and the second supply line 42 to the potential L of the continuous supply bus 40
- the piezoelectric actuator A2 is connected between the midpoint PM2 of the half-bridge inverter circuit 12, downstream of the inductor L2, and the second supply line 42 to the potential L of the bus feeding tinu 40.
- each the two piezoelectric actuators A1 and A2 can be controlled throughout its range of voltage deviation from zero to 100% U ma x, or 1000V according to the example. Since these control signals come from the logic implemented in the computer 50, it is thus possible to avoid any excessive variation of voltage applied across the actuators.
- a second case of use of the first control configuration relates to the case where a pair of piezoelectric actuators is connected in a face-to-face connection at the output of each half-bridge inverter circuit 1 1, 12 controlled in a controlled manner. independent by the control computer 50.
- a first pair of the piezoelectric actuator A3 / A4 is connected in a face-to-face connection at the output of the first half-bridge inverter circuit 1 1 and a second pair of piezoelectric actuator A5 / A6 is connected in a face-to-face connection at the output of the second half-bridge inverter circuit 12.
- one of the actuators of the pair is connected between the mid-point of the half bridge inverter circuit and the first power line 41 to the potential H of the DC supply bus 40 and the other actuator of the pair is connected between the midpoint of the inverter circuit in half. bridge and the second supply line 42 to the potential L of the DC bus 40.
- the actuators of each pair of actuators can thus be controlled over a range of voltages ranging from zero to 1000V thanks to the fact that the two inverter circuits e n half bridge 1 1, 12 can be controlled independently.
- the actuators can be protected against sudden voltage variations (at the start of the system, or at the time of actuator connection), by using the possibility that the computer 50 controls the output voltage of the actuator.
- AC / DC converter circuit 20 using the control signal PWM_DC, as will be described later.
- the two half-bridge inverter circuits 1 1 and 12 can also be controlled jointly by the control computer 50 according to a second control configuration, so as to pass the converter circuit 10 in "full bridge" topology, to generate negative voltages.
- a case of use of this second control configuration relates to the case where a piezoelectric actuator can be controlled with negative voltages, for example of the order of 20% U ma x, or -200V according to the example , thus allowing an amplitude gain, is connected to the output of the converter 10.
- such a piezoelectric actuator A7 is connected between the respective midpoints PM1 and PM2 of the two half-bridge inverter circuits 1 1 and 12, controlled in a coordinated manner by the control computer to change the converter circuit 10 into a "full bridge" topology, for an operating mode ranging from -20% U max to 100% U ma x, from -200V to 1000V according to the example.
- Another control configuration of the proposed topology which will be described below, is more particularly adapted to control piezoelectric actuators whose necessary power exceeds that of a single half-bridge type inverter circuit, previously exposed.
- This other control configuration consists in putting the two half-bridge inverter circuits 1 1 and 12 in parallel in order to increase the total power delivered to a high capacity actuator connected at the output.
- the actuator in question can be connected between the output connected to one of the two supply lines at the high or low potential of one of the two inverter circuits and the two midpoints, connected together, of the two circuits.
- semi-bridge type inverters can be connected between the output of the half-bridge inverter circuit 12 connected to the potential L of the DC supply bus 40 and the two mid-points PM1 and PM2 connected together.
- two half-bridge inverter circuits 1 1 and 12 respectively downstream inductances L1 and L2.
- This configuration makes it possible to double the intensity of the maximum current and may also have a beneficial impact on the residual voltages at the terminals of the output actuator.
- This alternative control configuration could also be applied to the control of a pair of piezoelectric actuators connected in output in a face-to-face arrangement.
- a user interface 60 cooperates with the control computer 50 so as to make it possible to select a control mode by the control computer 50 according to one or the other of said first and second control configurations, thus making it possible to adapt to different use cases mentioned.
- control computer 50 is adapted to control the AC / DC converter circuit 20 of in order to ensure a limited slope voltage rise up to U ma x of the DC supply bus 40 when energizing the actuators connected to the output of the converter circuit 10.
- the control computer 50 is adapted to provide a variable duty cycle PWM PWM type control signal for driving the switching transistor Tdc connected in series with the primary winding of the transformer 21 of the AC / DC converter circuit 20. More specifically, the control computer 50 is adapted to gradually increase the variable duty cycle of the PWM_DC control signal of the switching transistor Tdc, until reaching the maximum positive value U ma x on the DC supply bus 40 along said limited slope, and for maintain this variable duty cycle at a stationary value when the value U ma x is reached on the DC bus.
- the bus capacitor Cdc is associated with a controlled discharge circuit 70.
- the bus capacitor makes it possible to ensure sufficient reduction and smoothing of the current calls made by the inverter circuits 1 1 and 12 of the voltage converter circuit 10 to the AC / DC converter circuit 20.
- the discharge circuit 70 of the bus capacitor Cdc makes it possible for it to manage in a controlled manner the voltage drop on the bus when the piezoelectric actuators are stopped after use, to enable rapid safety during shutdown.
- the discharge circuit 70 comprises a discharge resistor 71 connected in parallel with the bus capacitor Cdc on the DC supply bus, upstream of the bus capacitor Cdc.
- a switch 72 is connected in series with the discharge resistor 71 between the supply lines of the DC supply bus.
- the discharge circuit 70 can be controlled between two states by the control computer, via a control signal "DC_discharge" of the switch 72 generated by the control computer, adapted to control a first state in which the charging current of the bus capacitor Cdc passes through the discharge resistor 71 connected in parallel with the DC supply bus, and a second state in which the discharge resistor 71 is short-circuited and the disconnection circuit disconnected from the DC bus Power.
- the discharge resistor 71 is connected to the DC supply bus when the switch 72 is controlled at closing by the control computer 50, together with a stop phase of the actuators connected to the output of the circuit. voltage converter 10.
- this discharge resistor 71 makes it possible to discharge in a controlled manner the bus capacitor Cdc during the extinction of the voltage converter circuit 10.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR1662550A FR3060905B1 (en) | 2016-12-15 | 2016-12-15 | CONTROL DEVICE FOR CAPACITIVE LOADS OF PIEZOELECTRIC ACTUATOR TYPE |
PCT/FR2017/053554 WO2018109387A1 (en) | 2016-12-15 | 2017-12-13 | Piezoelectric actuator type control device for capacitive loads |
Publications (1)
Publication Number | Publication Date |
---|---|
EP3556006A1 true EP3556006A1 (en) | 2019-10-23 |
Family
ID=58401742
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP17822413.5A Ceased EP3556006A1 (en) | 2016-12-15 | 2017-12-13 | Piezoelectric actuator type control device for capacitive loads |
Country Status (5)
Country | Link |
---|---|
US (1) | US11355691B2 (en) |
EP (1) | EP3556006A1 (en) |
CA (1) | CA3046902A1 (en) |
FR (1) | FR3060905B1 (en) |
WO (1) | WO2018109387A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20210123045A (en) * | 2020-04-02 | 2021-10-13 | 엘지전자 주식회사 | Method for discharging capacitor of resonant power conversion apparatus at initiating of operation and resonant power conversion apparatus thereof |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1138903B1 (en) * | 2000-04-01 | 2004-05-26 | Robert Bosch GmbH | Time- and event-controlled activation system for charging and discharging piezoelectric elements |
JP4479113B2 (en) * | 2001-02-23 | 2010-06-09 | 株式会社デンソー | Piezo actuator driving circuit and fuel injection device |
US9048775B2 (en) * | 2012-10-30 | 2015-06-02 | National Instruments Corporation | H-bridge for combined solenoid and piezo injection control |
-
2016
- 2016-12-15 FR FR1662550A patent/FR3060905B1/en active Active
-
2017
- 2017-12-13 US US16/470,363 patent/US11355691B2/en active Active
- 2017-12-13 EP EP17822413.5A patent/EP3556006A1/en not_active Ceased
- 2017-12-13 WO PCT/FR2017/053554 patent/WO2018109387A1/en unknown
- 2017-12-13 CA CA3046902A patent/CA3046902A1/en active Pending
Also Published As
Publication number | Publication date |
---|---|
WO2018109387A1 (en) | 2018-06-21 |
FR3060905B1 (en) | 2020-11-13 |
FR3060905A1 (en) | 2018-06-22 |
CA3046902A1 (en) | 2018-06-21 |
US20200091399A1 (en) | 2020-03-19 |
US11355691B2 (en) | 2022-06-07 |
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