EP3894820A1 - Dispositif capteur présentant un capteur piézoélectrique et un amplificateur de mesure - Google Patents

Dispositif capteur présentant un capteur piézoélectrique et un amplificateur de mesure

Info

Publication number
EP3894820A1
EP3894820A1 EP19813912.3A EP19813912A EP3894820A1 EP 3894820 A1 EP3894820 A1 EP 3894820A1 EP 19813912 A EP19813912 A EP 19813912A EP 3894820 A1 EP3894820 A1 EP 3894820A1
Authority
EP
European Patent Office
Prior art keywords
electrical
operational amplifier
voltage
amplifier
measuring
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.)
Withdrawn
Application number
EP19813912.3A
Other languages
German (de)
English (en)
Inventor
Marco Laffranchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kistler Holding AG
Original Assignee
Kistler Holding AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kistler Holding AG filed Critical Kistler Holding AG
Publication of EP3894820A1 publication Critical patent/EP3894820A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L23/00—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid
    • G01L23/22—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines
    • G01L23/221—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines
    • G01L23/222—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines using piezoelectric devices
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L23/00—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid
    • G01L23/22—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines
    • G01L23/221—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines
    • G01L23/225—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines circuit arrangements therefor
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/45—Differential amplifiers
    • H03F3/45071—Differential amplifiers with semiconductor devices only
    • H03F3/45076—Differential amplifiers with semiconductor devices only characterised by the way of implementation of the active amplifying circuit in the differential amplifier
    • H03F3/45475—Differential amplifiers with semiconductor devices only characterised by the way of implementation of the active amplifying circuit in the differential amplifier using IC blocks as the active amplifying circuit
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/261—Amplifier which being suitable for instrumentation applications
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2203/00—Indexing scheme relating to amplifiers with only discharge tubes or only semiconductor devices as amplifying elements covered by H03F3/00
    • H03F2203/45—Indexing scheme relating to differential amplifiers
    • H03F2203/45138—Two or more differential amplifiers in IC-block form are combined, e.g. measuring amplifiers

Definitions

  • the invention relates to a sensor arrangement with egg nem piezoelectric sensor and with a measuring amplifier such as a measuring amplifier for such a sensor arrangement according to the preamble of the independent claims.
  • a sensor measures a physical or chemical measurand and delivers a measuring signal.
  • the sensor is part of a sensor arrangement, which consists of the actual sensor and a downstream measuring amplifier.
  • the sensor supplies the measurement signal, which is derived to the measurement amplifier, and the measurement amplifier amplifies the derived measurement signal.
  • Sensor and measuring amplifier can be electrically connected to each other via a measuring cable.
  • the document EP2706337A2 relates to a capacitive sensor for measuring pressure during injection molding processes.
  • the capacitive sensor is in direct contact with a melt via a membrane, the melt is 400 ° C. and hotter.
  • the membrane is deflected out.
  • the membrane is part of an electrical capacitance.
  • the deflection changes the electrical capacity.
  • a temperature-induced change in capacity also occurs when the temperature changes.
  • the document EP2706337A2 teaches to switch an additional electrical shunt capacitance in parallel with the electrical capacitance.
  • the electrical shunt capacitance is designed in such a way that, when there is a change in temperature, for example when the temperature rises, it compensates for a temperature-indicated increase in the electrical capacitance by an equal reduction in the electrical shunt capacitance.
  • piezoelectric material In piezoelectric sensors, piezoelectric material generates electric polarization charges under the action of a force.
  • the electrical polarization charges can be tapped via electrodes on surfaces of the piezoelectric material.
  • the number of electrical polarizers Charge is proportional to the magnitude of the force acting on the piezoelectric material.
  • the number of electrical polarization charges is the measurement signal, it provides the magnitude of the force.
  • piezoelectric sensors are very sensitive, they measure the force with a measuring sensitivity of around 4pC / N. And such a small number of electrical polarization charges is falsified by the electrical thermal voltage in the piezoelectric sensor.
  • the invention relates to a sensor arrangement with egg nem a piezoelectric sensor and a measuring amplifier, which cher piezoelectric sensor is electrically connected to the measuring amplifier, which piezoelectric sensor delivers electrical polarization charges, which Messver amplifies electrical polarization charges of the piezoelectric sensor's; the measuring amplifier having at least one operational amplifier with two operational amplifier inputs and having an operational amplifier output, which electrical polarization charges are present at a first operational amplifier input; wherein at both Opera tion amplifier inputs there is an electrical voltage, which electrical voltage is not equal to a ground potential of the measuring amplifier; and wherein the voltage applied to the first operational amplifier is an electrical interference voltage, which interference voltage originates from an electrical thermal current generated in the piezoelectric sensor.
  • an electrical thermal voltage which arises after the Seebeck effect in the piezoelectric sensor, and which as an electrical interference voltage at the first operational amplifier. core input cannot be prevented. If this is the case, the electrical interference voltage is amplified from a capacitive negative feedback of the operational amplifier to an amplified electrical interference voltage. This is because the capacitive negative feedback of the operational amplifier regulates the two operational amplifier inputs of the operational amplifier to the same electrical voltage level. And the electrical voltage level of the second operational amplifier input of the operational amplifier is normally equal to the ground potential of the measuring amplifier, that is to say an electrical voltage of zero.
  • the amplified electrical interference voltage falsifies the measurement signal, which consists of an electrical output voltage, which is formed by the measuring amplifier from amplified electrical polarization charges.
  • the electrical voltage level of the second operational amplifier input is raised from the electrical voltage level of an electrical voltage from zero to the electrical voltage level of the electrical interference voltage at the first operational amplifier input , so that an identical electrical voltage is present at the operational amplifier inputs.
  • the invention also relates to a measuring amplifier for such a sensor arrangement; wherein the measuring amplifier has a compensator, which compensator is electrically connected to the second operational amplifier input; and where- the compensator forms the voltage applied to the second operational amplifier input.
  • FIG. 1 shows a first embodiment of a sensor arrangement 0 with a piezoelectric sensor 1, measuring cable 2 and measuring amplifier 3 with two charge amplifiers and a differential amplifier;
  • Fig. 2 shows a second embodiment of a sensor arrangement 0 with piezoelectric sensor 1, measuring cable 2 and measuring amplifier 3 with only one charge amplifier.
  • the sensor arrangement 0 measures a force, a torque, a pressure or an acceleration as a measured variable.
  • the sensor arrangement 0 comprises a piezoelectric sensor 1 and a measuring amplifier 3.
  • the function of the piezoelectric sensor 1 is to provide electrical polarization charges Q, Q 'which are derived from the measuring amplifier 3.
  • the function of the measuring amplifier 3 is to amplify the electrical polarization charges Q, Q '.
  • the materials of the piezoelectric sensor 1 are designed for permanently high operating temperatures of up to 1200 ° C.
  • the piezoelectric sensor 1 has a piezoelectric sensor element 11.
  • the piezoelectric sensor element 11 is cylindrical or hollow cylindrical and consists of piezoelectric crystal material such as quartz (S1O2 single crystal), calcium gallo germanate (Ca3Ga 2 Ge40i 4 or CGG), langasite (LasGasSiO ⁇ or LGS), tourmaline, gallium orthophosphate , etc.
  • the measured variable acts as a force F on the piezoelectric sensor element 11.
  • the force F is shown schematically in FIGS. 1 and 2 as an arrow, which acts on an upper outer surface of the piezoelectric sensor element 11.
  • the piezoelectric material generates electric polarization charges Q, Q '.
  • the electrical polarization charges Q, Q ' can be tapped on the outer surfaces of the piezoelectric sensor element 11.
  • the outer surfaces on which the electrical polarization charges Q, Q 'are generated are preferably completely electrically contacted with electrodes 112, 112'.
  • a first electrode 112 taps negative electrical polarization charges Q from the upper outer surface, and a second electrode 112' engages positive electric polarization charges Q 'from a lower outer surface.
  • the electrodes 112, 112 ' are electrically contacted with electrical conductors 12, 12'.
  • the Electrical conductors 12, 12 ' are wires or rods made of electrically conductive material such as pure metals, nickel alloys, cobalt alloys, iron alloys, etc.
  • the electrical conductors 12, 12' conduct the electrical polarization charges Q, Q 'tapped by the electrodes 112, 112'. from.
  • the first electrode 112 is in electrical contact with a first electrical conductor 12 and derives negative electrical polarization charges Q
  • the second electrode 112 ′ is in electrical contact with a second electrical conductor 12 ′ and derives positive electrical polarization charges Q ′.
  • the piezoelectric sensor 1 has a sensor housing 10.
  • the sensor housing 10 is made of mechanically and thermally resistant material such as pure metals, nickel alloys, cobalt alloys, iron alloys, etc.
  • the sensor housing 10 protects the piezoelectric element 10, the electrodes 112, 112 'and the electrical conductors 12, 12' from harmful environmental influences such as Impurities (dust, moisture, etc.).
  • the sensor housing 10 also forms an electromagnetic shield and protects the piezoelectric element 10, the electrodes 112, 112 'and the electrical conductors 12, 12' from electrical and electromagnetic interference effects in the form of electromagnetic radiation.
  • the sensor housing 20 is at a ground potential Ui.
  • the piezoelectric sensor 1 has an electrical insulation 13.
  • the electrical insulation 13 consists of electrically insulating and mechanically rigid material such as ceramic, A ⁇ CU ceramic, sapphire, etc.
  • the electrical insulation 13 has a specific volume resistance at 25 ° C. Ri, Ri 'stood on the order of 10 15 Qcm.
  • the electrical insulation 13 therefore only insulates the piezoelectric element 10, the first electrode 112 and the first electrical conductor 12 electrically from the sensor housing 10.
  • At least the piezoelectric sensor element 11 is permanently high operating temperatures of up to 1200 ° C sets. This is because, for the most accurate measurement possible, the piezoelectric sensor element 11 is spatially close to the measurement variable. sitioned and there is a large heat input. At other areas of the piezoelectric sensor 1 may have a lower permanent operating temperature, in particular if they are spatially distant from the measurement variable and heat input and heating are lower there.
  • Ri is an electrical thermal resistance between the electrodes 112, 112' and the ground potential
  • Ui lying sensor housing 10 denotes.
  • the electrical thermal current I T , I T '. flows over the electrical conductors 12, 12 ':
  • the sensor arrangement 0 can have a measuring cable 2, as shown in the embodiments according to FIGS. 1 and 2.
  • the measuring cable 2 connects the piezoelectric sensor 1 indirectly to the measuring amplifier 3.
  • the measuring cable 2 is optional, it may also be missing, then the piezoelectric sensor is connected directly to the measuring amplifier, which is not shown in the figure.
  • the measuring cable 2 can be 50cm or 50m long.
  • the measuring cable 2 can be reversibly or irreversibly connected to the piezoelectric sensor 1.
  • the connection can be a reversible plug connection or an irreversible integral connection.
  • the materials of the measuring cable 2 are designed for permanently high operating temperatures of up to 1200 ° C, but of at least 180 ° C.
  • the area of the sensor housing 10 in which the measuring cable 2 is connected to the piezoelectric sensor 1 therefore has a permanent operating temperature of up to 1200 ° C., but at least 180 ° C.
  • the measuring cable 2 has electrical conductors 22, 22 '.
  • the electrical conductors 22, 22 'of the measuring cable 2 are wires made of electrically conductive material such as pure metals, nickel alloys, cobalt alloys, iron alloys, etc.
  • two first ends of the electrical conductors 22, 22' of the measuring cable are formed 2 two inputs for electrical polarization charges Q, Q 'of the piezoelectric sensor 1.
  • a first electrical conductor 22 of the measuring cable 2 is in electrical contact with the first electrical conductor 12 of the piezoelectric sensor 1
  • a second electrical conductor 22 ′ of the measuring cable 2 is in electrical contact with the second electrical conductor 12 ′ of the piezoelectric sensor 1.
  • a first end of a first electrical conductor 22 of the measuring cable 2 forms an input for electrical polarization charges Q of the piezoelectric sensor 1.
  • the first electrical conductor 22 of the measuring cable 2 is connected to the first electrical conductor 12 of the piezoelectric sensor 1 electrically contacted.
  • the electrical conductors 22, 22 'of the measuring cable 2 derive the electrical polarization charges Q, Q' from the electrical conductors 12, 12 'of the piezoelectric sensor 1.
  • the first electrical conductor 22 of the measuring cable 2 derives negative electrical polarization charges Q which second electrical conductor 22 'of the measuring cable 2 derives positive electrical polarization charges Q'.
  • a second end of the first electrical conductor 22 of the measurement cable 2 forms an output for electrical polarization charges Q of the piezoelectric sensor 1.
  • the first electrical conductor 22 of the measurement cable 2 derives negative electrical polarization charges Q.
  • the measuring cable 2 has a cable jacket 20.
  • the cable sheath 20 has a network of mechanically and thermally Mix-resistant material such as pure metals, nickel alloys, cobalt alloys, iron alloys, etc.
  • the cable sheath 20 protects the electrical conductors 22, 22 'from harmful environmental influences such as impurities (dust, moisture, etc.).
  • the cable sheath 20 also forms an electromagnetic shield and protects the electrical conductors 22, 22 'from electrical and electromagnetic interference effects in the form of electromagnetic radiation.
  • the measuring cable 2 has electrical insulation 23.
  • the electrical insulation 23 insulates the electrical conductors 22, 22 'in the cable sheath 20 electrically from the cable sheath 20.
  • the electrical insulation 23 consists of ther up to temperatures of 1200 ° C, but at least 180 ° C resistant, electrically insulating material such as Ceramic, A ⁇ CU ceramic, sapphire, polytetrafluoroethylene, polyimide, hexafluoropropylene vinylidene fluoride copolymer (FKM), etc.
  • the electrical insulation 23 has a volume resistance at 25 ° C in the order of 10 15 Qcm.
  • the measuring amplifier 3 is connected to the piezoelectric sensor 1.
  • the measuring amplifier 3 can be connected to the piezoe lectric sensor 1, as shown in the embodiments according to FIGS. 1 and 2, indirectly via a measuring cable 2.
  • the measuring amplifier can, however, also be connected directly downstream of the piezoelectric sensor, so that a measuring cable is missing, but this is not shown in the figure.
  • the measuring amplifier 3 can be reversibly or irreversibly connected to the piezoelectric sensor 1 or to the measuring cable 2.
  • the connection can be reversible Plug connection or an irreversible cohesive connection.
  • the materials of the measuring amplifier 3 are designed for persistently high operating temperatures of up to 60 ° C.
  • the measuring amplifier 3 is connected in some areas directly to the piezoelectric sensor 1, which is not shown in the figure, then this area of the measuring amplifier 3 has a permanent operating temperature of at most 60 ° C.
  • the measuring amplifier 3 has a measuring amplifier housing 30.
  • the amplifier housing 30 is made of permanent permanent material such as aluminum, plastic, etc.
  • the amplifier housing 30 protects the electrical circuit from harmful environmental influences such as impurities (dust, moisture, etc.).
  • the amplifier housing 30 also forms an electromagnetic shield and protects the electrical circuit from electrical and electromagnetic interference effects in the form of electromagnetic radiation.
  • the measuring amplifier housing 30 is at a ground potential U 3 .
  • the measuring amplifier 3 has electrical conductors 32, 32 '. Ends of the electrical conductors 32, 32 'form inputs for electrical polarization charges Q, Q' for the electrical circuitry of the measuring amplifier 3.
  • the electrical conductors 32, 32 ' are wires made of electrically conductive material such as pure metals, nickel alloys, cobalt alloys, iron alloys, etc.
  • the electrical conductors 32, 32 'of the measuring amplifier 3 derive the electrical polarization charges Q, Q' for the electrical switching of the measuring amplifier 3.
  • a first electrical conductor 32 of the measuring amplifier 3 is in electrical contact with the first electrical conductor 22 of the measuring cable 2 and derives negative electrical polarization charges Q
  • a second electrical conductor 32 'of the measuring amplifier 3 is connected makes electrical contact with the second electrical conductor 22 'of the measuring cable 2 and derives positive electrical polarization charges Q'.
  • only the first electrical conductor 32 of the measuring amplifier 3 is in electrical contact with the first electrical conductor 22 of the measuring cable 2 and derives negative electrical polarization charges Q.
  • a first electrical conductor of the measuring amplifier is electrically contacted with the first electrical conductor of the piezoelectric sensor, and a second electrical conductor of the measuring amplifier is electrically contacted with the second electrical conductor of the piezoelectric sensor.
  • the measuring amplifier 3 has two charge amplifiers, each consisting of an operational amplifier 33, 33 ', a capacitor 34, 34', an electrical resistor 35, 35 ', and the measuring amplifier 3 has a differential amplifier 37.
  • the measuring amplifier 3 has only one charge amplifier, consisting of an operational on amplifier 33, a capacitor 34 and an electrical resistor 35.
  • the measuring amplifier 3 is at the ground potential Uo.
  • the ground potential Uo of the measuring amplifier 3 is the virtual ground of the measuring amplifier 3.
  • the ground potential Uo of the measuring amplifier 3 is short-circuited to the ground potential U3 of the measuring amplifier housing 3.
  • the operational amplifier 33, 33 ' has a first operational amplifier input 331, 331', a second operational amplifier input 332, 332 'and an operational amplifier output 333, 333'.
  • the electrical polarization charges Q, Q ' are conducted via the electrical conductors 32, 32' of the measuring amplifier 3 to the first operational amplifier inputs 331, 331 '.
  • negative electrical polarization charges Q are present at the first operational amplifier input 331 of a first operational amplifier 33
  • positive electrical polarization charges Q ' are present at the first operational amplifier input 331' of a second operational amplifier 33 '.
  • only negative electrical polarization charges Q are present at the first operational amplifier input 331 of the single operational amplifier 33.
  • the capacitance 34, 34 ' is connected in parallel between the operational amplifier output 333, 333' and the first operational amplifier input 331, 331 '.
  • the operational amplifier 33, 33' is capacitively coupled.
  • the capacitive negative feedback controls the operational amplifier output 333, 333 'in such a way that capacitive negative electrical charges flow from the operational amplifier output 333, 333' via the capacitance 34, 34 'to the first operational amplifier input 332, 332' and that an electrical charge difference is input to the operational amplifier gears 331, 331 ', 332, 332' on the electrical voltage level of the electrical voltage at the second operational amplifier input 332 is held.
  • the electrical resistor 35, 35 ' is also connected in parallel between the operational amplifier output 333, 333' and the first operational amplifier input 331, 331 '.
  • the electrical resistor 35, 35 ' eliminates zero point errors of the operational amplifier 33, 33'.
  • Such zero point errors of the operational amplifier 33, 33 ' have different causes such as an electrical offset voltage at the first operational amplifier input 331, 331' originating from the components of the operational amplifier 33, 33 ', aging of the operational amplifier 33, 33', etc.
  • the operational amplifier 33, 33 ' amplifies the electrical polarization charges Q, Q'.
  • the amplification of the electrical polarization charges Q, Q ' is proportional to the size of the capacitance 34, 34'.
  • Electrical amplifier voltages U, U ' are then present at the operational amplifier outputs 333, 333', which are proportional to the electrical polarization charges Q, Q ', but have an inverted sign.
  • a positive electrical amplifier voltage U is then present at the operational amplifier output 333.
  • a negative electrical amplifier voltage U ' is present at the operational amplifier output 333'.
  • the differential amplifier 37 has two differential amplifier inputs 371, 372 and a differential amplifier output 373.
  • a first differential amplifier input 371 is electrically connected to the operational amplifier output 333 of the first operational amplifier 33, so that the positive electrical amplifier voltage U is present there.
  • a second differential amplifier input 372 is electrically connected to the operational amplifier output 333 of the second operational amplifier 33 ', so that the negative electrical amplifier voltage U' is present there.
  • the differential amplifier 37 forms at the differential amplifier output 373 an electrical output voltage U ′′ of the measuring amplifier 3.
  • the electrical output voltage U ′′ of the measuring amplifier 3 is a difference between the electrical amplifier voltages U, U f applied to the differential amplifier inputs 371, 372.
  • the applied to the Differentialver amplifier inputs 371, 372 electrical amplifier voltages U, U f have different signs and are added to the electrical output voltage U ''.
  • the second embodiment according to FIG. 2 has no differential amplifier, where the electrical amplifier voltage U is an electrical output voltage of the measuring amplifier 3. If the piezoelectric sensor 1 is permanently exposed to a high operating temperature of up to 1200 ° C, an electrical thermal voltage U T , U t 'arises after the Seebeck effect and generates an electrical thermal current I T , I T ' ⁇ Der electrical thermal current I T , I T 'flows via the electrical conductors 12, 12', 22, 22 ', 32, 32' from the piezoelectric sensor 1 to the measuring amplifier 3 and is present as an electrical interference voltage U s , U s ' at the first operation ver stronger inputs 331, 331 '.
  • an electrical interference voltage U s, U s' is present and as long as the the first operational amplifier input 331, 331' abutting electrical interference voltage U s, U s' of the second operational amplifier input 332, 332 'applied electrical voltage U K, U K 'differs in the electrical voltage level, for example when the electrical voltage U K , U k ' applied to the second operational amplifier input 332, 332 'is equal to the ground potential Uo of the measuring amplifier 3, that is to say is equal to an electrical voltage of zero, as long as the capacitive negative feedback increases of the operational amplifier 33, 33 'the electrical interference voltage U s , U s ' applied to the first operational amplifier input 331, 331' to an amplified electrical interference voltage U s *, U s ' * applied to the operational amplifier output 333, 333 '.
  • a compensator 36, 36 ' is electrically connected to the non-vertical, second operational amplifier input 332, 332'.
  • the compensator 36, 36 ' forms the electrical voltage U K , U K ' applied to the second operational amplifier input 332, 332 '.
  • the compensator 36, 36 ' is connected in parallel between the operational amplifier output 333, 333' and the second operational amplifier input 332, 332 '.
  • an amplified electrical interference voltage U s *, U s '* is present at the operational amplifier output 333, 333'
  • the compensator 36, 36 ' changes with the amplified electrical interference voltage U s *, U s ' * the electrical voltage level of the amplifier input at the second operational amplifier 332, 332 'applied voltage U K , U K '.
  • the compensator 36, 36 ' changes the voltage U K , U K ' applied to the second operational amplifier input 332, 332 'until the voltage applied to the second operational amplifier input 332, 332' is identical to the electrical voltage U K , U K ' with the electrical interference voltage U s , U s 'present at the first operational amplifier input 331, 331'.
  • the compensator then generates an electrical compensation voltage U K , U k ', which is present as an electrical voltage U K , U K ' at the second operational amplifier input 332, 332 '.
  • the compensator 36, 36 ' has a controller unit 362, 362'. An input of the controller unit 362, 362 'is indirectly electrically connected to the operational amplifier output 333, 333'. An output of the controller unit 362, 362 'is electrically connected to the second operational amplifier input 332, 332'.
  • the compensator 36, 36 ' changes with the electrical compensation charge I k , Ik' at the second operational amplifier input 332, 332 'applied electrical voltage U K , U k ' TO an electrical compensation voltage U K , U K '.
  • the compensator 36, 36 allows the controller unit 362, 362' to flow in the amount and time as long as electrical compensation charge I k , Ik 'until the compensation voltage U K applied to the second operational amplifier input 332, 332' , U k 'is identical to the electrical interference voltage U s , U s ' applied to the first operational amplifier input 331, 331'.
  • the second operational amplifier input 332, 332' is applied compensation voltage U K, U K 'is identical with the first Operational amplifier input 331, 331 'applied electrical interference voltage U s , U s ', and the electrical interference voltage U s , U s ' is proportional to the size of the operating temperature T of the piezoelectric sensor 1.
  • the compensator 36, 36 ' has a filter unit 361, 361'.
  • Filter unit 361, 361 'and controller unit 362, 362' are connected in series.
  • An input of the filter unit 361, 361 ' is electrically connected to the operational amplifier output 333, 333'.
  • An output of the filter unit 361, 361 ' is electrically connected to the input of the controller unit 362, 362'.
  • the input of the controller unit 362, 362 ' is thus indirectly connected via the filter unit 361, 361' to the operational amplifier output 333, 333 '.
  • the capacitive negative feedback of the operational amplifier 33, 33' produces one amplified electrical interference voltage U s *, U s '* present at the operational amplifier output 333, 333'.
  • the operational amplifier output 333, 333 ' there is then an electrical amplifier voltage U, U' and an amplified electrical interference voltage U s *, U s ' *.
  • the electrical amplifier voltage U, U ' has a time duration from lCv 6 sec to lsec, and Increased electrical interference voltage U s *, U s ' * has a time duration of more than 10 seconds.
  • the compensator 36, 36 ' filters with the filter unit 361, 361' electrical amplifier voltage U, U 'with a time duration from 10 6 sec to lsec and only increased electrical interference voltage U s *, U s ' * with a time Duration of more than 10 seconds reaches controller unit 362, 362 '.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Amplifiers (AREA)

Abstract

L'invention concerne un dispositif capteur (0) présentant un capteur piézoélectrique (1) et un amplificateur de mesure (3), lequel capteur piézoélectrique (1) est relié électriquement à l'amplificateur de mesure (3), lequel capteur piézoélectrique (1) fournit des charges de polarisation électriques (Q, Q'), lequel amplificateur de mesure (3) amplifie les charges de polarisation électriques (Q, Q') du capteur piézoélectrique (1). L'amplificateur de mesure (3) présente au moins un amplificateur de fonctionnement (33, 33') présentant deux entrées d'amplificateur de fonctionnement (331, 331', 332, 332') et une sortie d'amplificateur de fonctionnement (333, 333'), lesquelles charges de polarisation électriques (Q, Q') sont appliquées à une première entrée d'amplificateur de fonctionnement (331, 331'). Une tension électrique (US, US', UK, UK') est appliquée aux deux entrées d'amplificateur de fonctionnement (331, 331', 332, 332'), laquelle tension électrique (US, US', UK, UK') est différente d'un potentiel de la masse (U0) de l'amplificateur de mesure (3). La tension électrique (US, US') appliquée à la première entrée d'amplificateur de fonctionnement (331, 331') est une tension électrique parasite (US, US'), laquelle tension électrique parasite (US, US') provient d'un flux thermique électrique (IT, IT') généré dans le capteur piézoélectrique (1).
EP19813912.3A 2018-12-14 2019-12-11 Dispositif capteur présentant un capteur piézoélectrique et un amplificateur de mesure Withdrawn EP3894820A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP18212659 2018-12-14
PCT/EP2019/084687 WO2020120593A1 (fr) 2018-12-14 2019-12-11 Dispositif capteur présentant un capteur piézoélectrique et un amplificateur de mesure

Publications (1)

Publication Number Publication Date
EP3894820A1 true EP3894820A1 (fr) 2021-10-20

Family

ID=64665663

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19813912.3A Withdrawn EP3894820A1 (fr) 2018-12-14 2019-12-11 Dispositif capteur présentant un capteur piézoélectrique et un amplificateur de mesure

Country Status (2)

Country Link
EP (1) EP3894820A1 (fr)
WO (1) WO2020120593A1 (fr)

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8150602B2 (en) * 2007-11-08 2012-04-03 Honeywell International Inc. Method and system for estimating in-cylinder pressure and knocking utilizing an in-cylinder pressure sensor
JP5883290B2 (ja) * 2011-12-28 2016-03-09 シチズンファインデバイス株式会社 圧力検出装置およびチャージアンプ回路
JP5901982B2 (ja) * 2012-01-30 2016-04-13 シチズンファインデバイス株式会社 検出システムおよび検出装置
US9103738B2 (en) 2012-09-07 2015-08-11 Dynisco Instruments Llc Capacitive pressure sensor with intrinsic temperature compensation
FR2996639B1 (fr) * 2012-10-05 2014-11-07 Continental Automotive France Circuit amplificateur de mesure ameliore pour capteur piezo-electrique positionne dans un moteur a combustion interne
JP6409148B1 (ja) * 2018-08-28 2018-10-17 シチズンファインデバイス株式会社 圧力検出装置、処理回路

Also Published As

Publication number Publication date
WO2020120593A1 (fr) 2020-06-18

Similar Documents

Publication Publication Date Title
EP1797603B1 (fr) Element capteur comprenant au moins un element de mesure a proprietes piezoelectriques et pyroelectriques
DE69111337T2 (de) Druckmassfühler.
EP2002253B1 (fr) Capteur de gaz
DE102011113002A1 (de) Differenzstromsensor
EP2904363B1 (fr) Capteur de pression doté d'une couche de recouvrement
DE2900382A1 (de) Spannungsmesser-druckwandlergeraet
EP0065511A1 (fr) Instrument de mesure avec un élément de détection piézoélectrique
DE3200362C2 (de) Prüfeinrichtung zur Bestimmung der Schwingungseigenschaften von Meßwertaufnehmern oder Meßwertaufnahmesystemen mit piezoelektrischen Meßelementen
WO1992018856A1 (fr) Dispositif integrable de mesure de la conductivite
DE102011076105A1 (de) Sensorelement mit piezoelektrischem Wandler
DE102011107856A1 (de) Temperatursensor mit Mitteln zur in-situ Kalibrierung
DE102005051848B4 (de) Schaltungsanordnung zur temperaturdriftkompensierten Strommessung
EP3894820A1 (fr) Dispositif capteur présentant un capteur piézoélectrique et un amplificateur de mesure
DE202016008592U1 (de) Sensor
EP0017901B1 (fr) Circuit de mesure électrique de grandeurs mécaniques
DE102020100675A1 (de) Kapazitiver Drucksensor mit Temperaturerfassung
EP1962070B1 (fr) Capteur haute température et procédé pour sa vérification
DE102010024711A1 (de) Vorrichtung und Verfahren zum Erfassen mechanischer Lasten auf Schubelementen
DE102008043326A1 (de) Verfahren und Vorrichtung zur Widerstandsmessung eines von einer chemischen und/oder physikalischen Messgröße abhängigen Widerstandselements
EP4194830B1 (fr) Capteur de force résistif et capacitif et procédé de fonctionnement de celui-ci
DE102008055774B4 (de) Vorrichtung zum Messen einer Temperatur eines Bauteils und Vorrichtung zum Messen einer Dehnung eines Bauteils
DE102007054027B4 (de) Vorrichtung und Verfahren zur kapazitiven Kraftmessung
DE102009038378A1 (de) Kapazitiver Differenzdrucksensor
DE102015213986A1 (de) Sensoreinrichtung und Verfahren zum Erfassen von Druck
DE102019111695A1 (de) Messvorrichtung

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20210520

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20220915