EP3903088A1 - Capteur de particules et procédé pour le faire fonctionner - Google Patents
Capteur de particules et procédé pour le faire fonctionnerInfo
- Publication number
- EP3903088A1 EP3903088A1 EP19801322.9A EP19801322A EP3903088A1 EP 3903088 A1 EP3903088 A1 EP 3903088A1 EP 19801322 A EP19801322 A EP 19801322A EP 3903088 A1 EP3903088 A1 EP 3903088A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- electrode
- particle sensor
- corona
- particle
- voltage
- 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- Withdrawn
Links
- 239000002245 particle Substances 0.000 title claims abstract description 133
- 238000000034 method Methods 0.000 title claims description 7
- 239000012530 fluid Substances 0.000 claims abstract description 34
- 229910010293 ceramic material Inorganic materials 0.000 claims description 3
- 239000012777 electrically insulating material Substances 0.000 claims description 3
- 238000002485 combustion reaction Methods 0.000 description 11
- 150000002500 ions Chemical class 0.000 description 11
- 239000004071 soot Substances 0.000 description 6
- ORQBXQOJMQIAOY-UHFFFAOYSA-N nobelium Chemical compound [No] ORQBXQOJMQIAOY-UHFFFAOYSA-N 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000005684 electric field Effects 0.000 description 3
- 239000000443 aerosol Substances 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011017 operating method Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/0656—Investigating concentration of particle suspensions using electric, e.g. electrostatic methods or magnetic methods
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
- H01T19/00—Devices providing for corona discharge
- H01T19/04—Devices providing for corona discharge having pointed electrodes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N2015/0042—Investigating dispersion of solids
- G01N2015/0046—Investigating dispersion of solids in gas, e.g. smoke
Definitions
- the disclosure relates to a particle sensor with a particle charging device for charging particles in a fluid stream.
- the disclosure further relates to a method for operating such a particle sensor.
- Preferred embodiments relate to a particle sensor with a particle charging device for charging particles in a fluid stream, the particle charging device having a corona electrode for generating a corona discharge, and wherein the particle sensor has a trapeze electrode for deflecting charged particles of the fluid stream, wherein the
- Corona electrode and trapezoidal electrode can be controlled with the same control signal. This results in a low level of complexity because only the one control signal is provided for the corona electrode and the trapezoidal electrode.
- the fluid flow can be an exhaust gas flow from an internal combustion engine of a motor vehicle.
- the particles can be soot particles, such as those that arise during the combustion of fuel by an internal combustion engine.
- the principle according to the embodiments can be used both for sensing and as a solid
- trained particles e.g. soot particles, as they are contained in an exhaust gas stream of an internal combustion engine
- liquid particles e.g. aerosol
- comparatively light (low-mass) charged particles which are not attached by means of the trapezoidal electrode particles to be measured charged to the particle charging device, such as ions of the fluid flow, are comparatively strongly deflected, so that these do not reach the charge measuring device, which is further downstream with respect to the fluid flow, or only in a greatly reduced number.
- Sensor electrode of the charge measuring device where they can be detected on the sensor electrode by means of charge influence, for example.
- Signal line is provided, which is electrically conductively connected to the corona electrode and to the trapeze electrode. These are via this signal line
- Corona electrode and trapezoidal electrode can be acted upon with the control signal. Only this one signal line is advantageously provided in order to control both electrodes mentioned.
- a reference potential for example the ground potential
- Corona electrode and the trapezoidal electrode can be controlled.
- Particle sensor has an optional sensor electrode for recording information about charged particles. This allows a measurement of the particle charge e.g. about charge influence or the mirror charge principle at the
- the particle charge is measured using the “escaping currenf principle”.
- the complete system containing the particle sensor can be isolated from the outside (in particular, this makes an optional counter electrode for the corona electrode and any counter electrode for the trapezoidal electrode “virtual”, for example a virtual ground electrode), and an electrical current is measured which the charged particles form their electrical charge out of the otherwise electrically insulated and therefore closed system.
- the electrical current under consideration flows from the corona electrode through the corona discharge into the counter electrode of the corona electrode, and the trapezoidal electrode captures the remaining ions.
- the current generated by the charged particles must be added to the counter electrode so that its electrical potential remains constant. It is known as the "escaping current” and is a measure of the concentration of charged particles.
- Corona electrode emitted electric current carried by ions and particles, the ions e.g. are trapped by the trapezoidal electrode and the charged particles e.g. escape from the system.
- the current that corresponds to the charged particles escaping from the system must be compensated ("escaping current").
- Particle sensor has a carrier element made of an electrically insulating material, in particular a ceramic material.
- Carrier element are arranged.
- Particle sensor has a control device for generating the control signal.
- Control device is designed to the corona electrode
- the trapezoidal electrode With a first voltage during a first time period and to drive it with a second voltage during a second time period following the first time period, which voltage is lower than the first voltage.
- the aforementioned corona discharge can be generated, by means of which an electrical charge of the particles of the fluid flow is possible, and during the second time period the voltage can be reduced to a value corresponding to the second voltage, which effectively traps (trapping light charged particles such as ions), but no longer generates the corona discharge.
- a third time range can be provided between the first time range and the second time range, in which the corona electrode and the trapeze electrode are controlled, in particular by means of the control device, with a third voltage that is lower than the second voltage.
- the third voltage can also be zero.
- Control device is designed to have a duration of the first time range and / or a duration of the second time range as a function of a
- Fluid flow rate to choose. This allows operation of the corona electrode and trapezoidal electrode to the speed of the fluid flow, e.g. an exhaust gas velocity.
- the particle charging device having a corona electrode for generating a corona discharge, and wherein the particle sensor has a trapeze electrode for deflecting charged particles of the fluid stream, the corona electrode and the trapeze electrode being driven with the same drive signal.
- Trapel electrode is driven with a first voltage during a first time period and is driven with a second voltage that is lower than the first voltage during a second time period following the first time period.
- Figure 1 schematically shows a side view of a particle sensor according to
- Figure 2 schematically shows a side view of a particle sensor in one
- FIG. 3A schematically shows a side view of a particle sensor according to FIG.
- FIG. 3B schematically shows the particle sensor according to FIG. 3A in a second
- FIG. 4 schematically shows a time course of a control signal according to further preferred embodiments
- FIG. 5 schematically shows a simplified flow diagram of a method according to further preferred embodiments.
- FIG. 6 schematically shows a block diagram of a particle sensor according to
- FIG. 1 schematically shows a side view of a particle sensor 100 according to preferred embodiments.
- the particle sensor 100 has one
- Particle charging device 110 for charging particles P in a fluid stream A1, which moves along a horizontal coordinate x in FIG. 1.
- the fluid flow A1 can be an exhaust gas flow from an internal combustion engine of a motor vehicle.
- the particles P can be Soot particles act as they arise in the course of combustion of fuel by an internal combustion engine.
- the particle charging device 1 10 has a corona electrode 1 12
- the corona electrode 112 and the trapezoidal electrode 120 can be controlled with the same control signal S1. This results in a low level of complexity because only the one control signal S1 is provided for the corona electrode 112 and the trapeze electrode 120.
- the principle according to the embodiments can be used both for sensing particles P, P '(for example soot particles as contained in an exhaust gas stream of an internal combustion engine) as solid bodies, as well as for sensing e.g. liquid particles (e.g. aerosol) can be used.
- comparatively light (low-mass) charged particles which do not adhere to particles P ′ to be measured, which are charged by means of the particle charging device 110, such as ions of the fluid flow A1, for example, can be deflected comparatively strongly by means of the trapeze electrode 120, so that they do not or only deflect in a greatly reduced number to one further downstream with respect to the fluid flow A1
- Trapezoidal electrode 120 for example to an optional sensor electrode 140 of the charge measuring device, where they can be detected, for example, by means of charge influence on the sensor electrode 140.
- Signal line 130 is provided, which is electrically conductively connected to the corona electrode 1 12 and to the trapeze electrode 120.
- the corona electrode 112 and the trapezoidal electrode 120 with the control signal are via this signal line 130 S1 acted upon.
- this one signal line 130 is advantageously provided in order to control both electrodes 112, 120 mentioned.
- Corona electrode 112 and trapezoidal electrode 120 are subjected to a predeterminable electrical potential by means of the control signal S1 (e.g. charged or discharged or recharged), a potential difference between the predefinable electrical potential and a reference potential,
- the ground potential which corresponds to an electrical voltage with which the corona electrode 112 and the trapeze electrode 120 are controlled.
- Particle sensor 100 has an optional sensor electrode 140 (FIG. 1) for detecting information about charged particles P '. This allows a measurement of the particle charge e.g. via the influence of charge or the mirror charge principle on the sensor electrode 140.
- the complete system containing the particle sensor 100 is isolated from the outside (in particular, an optional counter electrode for the corona electrode and an optional counter electrode for the trapezoidal electrode, for example, a “virtual” electrode, for example a virtual ground electrode), and an electrical current is measured, which remove the charged particles P 'in the form of their electrical charge from the otherwise electrically insulated and therefore closed system.
- the electrical current under consideration flows from the corona electrode 1 12 through the corona discharge C into the counter electrode 1 12 ′ of the corona electrode, and the trapeze electrode 120 captures the remaining ions.
- the current which is generated by the charged particles P 'must be added to the counter electrode 112' again so that its electrical potential remains constant. It is called "escaping current” and is a measure of the concentration of charged particles P '.
- Particle sensor 100 has a carrier element 102 made of an electrically insulating material, in particular made of a ceramic material (“ceramic substrate”).
- ceramic substrate a ceramic material
- Corona electrode 112 and trapezoidal electrode 120 are arranged on the same surface 102a of carrier element 102.
- Particle sensor 100 a control device 150 for generating the
- FIG. 2 schematically shows the arrangement of the particle sensor 100 according to FIG. 1 in a target system Z, which in the present case is an exhaust tract of an internal combustion engine, for example a motor vehicle.
- a target system Z which in the present case is an exhaust tract of an internal combustion engine, for example a motor vehicle.
- Exhaust gas flow is designated in the present case with the reference symbol A2.
- a protective tube arrangement 1000 consisting of two tubes R1, R2 arranged concentrically to one another, the particle sensor 100 being arranged in the inner tube R1 such that the surface 102a of the carrier element 102 (FIG. 1) is essentially parallel to a longitudinal axis LA of the inner one Tube R1 runs. Because of the different lengths and the arrangement of the tubes R1, R2 relative to one another, other preferred ones result
- the arrangement shown in FIG. 2 results in a comparatively uniform overflow (in particular in the form of a laminar flow) of the
- Particle sensor 100 or its first surface 102a aligned along the fluid flow P1 causes an efficient detection of in the
- the particle sensor 100 is protected from direct contact with the main exhaust gas stream A2.
- the elements 100, R1, R2 are therefore advantageously one
- the reference symbol R2 indicates an optional electrical connection of the outer tube R2 and / or the inner tube R1 with a reference potential such as the ground potential, so that the pipe in question or both pipes can advantageously be used simultaneously for their fluidic guiding function as an electrical counterelectrode, for example for the trap electrode 120 (and / or for the corona electrode 112), see FIG. 1.
- the inner tube R1 can form a counter electrode for the corona electrode 112 and the trapeze electrode 120 which is at ground potential.
- the block arrow P5 in FIG. 2 symbolizes an optional fresh gas supply, in particular fresh air supply, which may be desired in some embodiments, but is not provided in particularly preferred embodiments.
- FIG. 3A schematically shows a side view of a particle sensor 100a according to further preferred embodiments in a first operating phase.
- the tube R1 (cf. also FIG. 2) serves as the counter electrode 1 12 'for the corona electrode 1 12 and the trapeze electrode 120.
- An electrical field C' thus forms between the corona electrode 112 and the tube R1.
- the control signal S1 for the electrodes 112, 120 is another preferred one Embodiments are advantageously chosen so that the aforementioned corona discharge C (FIG. 1) forms, as a result of which the charged particles PC are generated.
- FIG. 3B schematically shows the particle sensor 100a according to FIG. 3A in a second operating phase, which follows, for example, the first operating phase. Due to a non-vanishing speed of the fluid flow A1, the cloud PC of charged particles has now moved further along the coordinate x (FIG. 1) and is located approximately in the area of the trapeze electrode 120, that is to say between the corona electrode 112 and the optional sensor electrode 140.
- the control signal S1 can advantageously be selected such that, for example, the corona discharge C (FIG.
- a first time period T1 (starting with the time tO, for example corresponding to the first operating phase according to FIG 3A) to be driven with a first voltage U1 and to be driven with a second voltage U2 which is lower than the first voltage U1, for example up to a further time, during a second time period T2 following the first time period T1 (starting at time t1) t2, for which the control signal S1 is optionally set to 0 volts.
- Corona discharge C (Fig. 1) are generated by means of an electrical
- Charging the particles P of the fluid stream A1 is possible, and during the second time period T2 (FIG. 4) the voltage can be reduced to a smaller value corresponding to the second voltage U2, which is an effective trapping (trapping of lightly charged particles such as ions ) enables, but e.g. no more generation of corona discharge C.
- a third time range (not shown) can be provided between the first time range T1 and the second time range T2, in which the corona electrode 112 and the trapeze electrode 120, in particular by means of the control device 150, with a third
- Voltage (not shown) are driven, which is less than the second voltage U2.
- the third voltage can also be zero.
- Control device 150 (FIG. 1) is designed to select a duration of the first time range T1 and / or a duration of the second time range T2 (and / or a duration of the aforementioned optional third time range) as a function of a speed of the fluid flow A1.
- operation of the corona electrode 112 and the trapeze electrode 120 can be matched to the speed of the fluid flow A1, for example an exhaust gas speed.
- Further preferred embodiments relate to a method for operating a particle sensor with a particle charging device
- Charging particles in a fluid stream having a corona electrode for generating a corona discharge, and wherein the particle sensor has a trapeze electrode for deflecting charged particles of the fluid stream, the corona electrode and the trapeze electrode being driven with the same drive signal. This is indicated by step 200 of the flow chart according to FIG. 5.
- Trapel electrode 1 12 (FIG. 1) is driven with a first voltage U1 during a first time period T1 (FIG. 4), cf. Step 200 from FIG. 5) and during a second time period following the first time period T1 (FIG. 4)
- Time range T2 is controlled with a second voltage U2, cf. Step 202 from FIG. 5), which is lower than the first voltage U1.
- FIG. 6 schematically shows a block diagram of a particle sensor 100b according to further preferred embodiments.
- a control device 150 ′′ for generating the control signal S1 is connected via a single signal line 130 ′′ to the carrier element 102 or the electrodes 112, 120 arranged thereon, in order to apply the control signal S1 to these two electrodes 112, 120.
- Reference numeral 152 may also symbolize optional lines, e.g. a sensor signal line assigned to the optional sensor electrode 140 (FIG. 1).
- the principle according to the embodiments advantageously enables a reduction in the number of signal lines which have a comparatively large electrical potential (in conventional systems, for example, two signal lines for two electrodes).
- a single signal line 130, 130 ′ is provided for the (simultaneous) control of the corona electrode 132 and the trapeze electrode 120, as a result of which, among other things, complexity can be reduced and costs can be saved.
- the full functionality in particular with regard to the generation of the corona discharge C and / or an electric field in the trapezoidal electrode 120
- the electrodes 1 12, 120 can be operated in a pulsed manner, the control signal S1 shown by way of example in FIG. 4 between the times t0 and t2 can be repeated periodically, for example.
- the trapezoidal electrode 120 is designed (comparatively large radii of curvature, roundings, no peaks) in such a way that - in particular in the first time range T1 (FIG. 4) - there is no corona discharge.
- information about the exhaust gas flow from an engine control unit of an internal combustion engine generating the exhaust gas flow A1 (FIG. 1) and / or application data can be obtained via a
- Flow guidance P1, P2, P3, P4 can be used in the particle sensor to calculate an exhaust gas velocity in the particle sensor.
- switching times T1, T2 for the voltages U 1, U2 on the corona electrode 112 and the trapezoidal electrode can be precisely calculated and / or applied based on this information.
- the principle according to the embodiments can be advantageous
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- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Biochemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Dispersion Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
Abstract
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102018251790.8A DE102018251790A1 (de) | 2018-12-28 | 2018-12-28 | Partikelsensor und Betriebsverfahren hierfür |
PCT/EP2019/080667 WO2020135943A1 (fr) | 2018-12-28 | 2019-11-08 | Capteur de particules et procédé pour le faire fonctionner |
Publications (1)
Publication Number | Publication Date |
---|---|
EP3903088A1 true EP3903088A1 (fr) | 2021-11-03 |
Family
ID=68503152
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19801322.9A Withdrawn EP3903088A1 (fr) | 2018-12-28 | 2019-11-08 | Capteur de particules et procédé pour le faire fonctionner |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP3903088A1 (fr) |
DE (1) | DE102018251790A1 (fr) |
WO (1) | WO2020135943A1 (fr) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3992607A1 (fr) * | 2020-10-28 | 2022-05-04 | Heraeus Nexensos GmbH | Capteur de détection de particules conductrices |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3165898A4 (fr) * | 2014-07-04 | 2017-06-28 | Shimadzu Corporation | Dispositif de charge de particules et dispositif de classification de particules à l'aide dudit dispositif de charge |
DE102017208849A1 (de) * | 2017-05-24 | 2018-11-29 | Robert Bosch Gmbh | Partikelsensor und Herstellungsverfahren hierfür |
-
2018
- 2018-12-28 DE DE102018251790.8A patent/DE102018251790A1/de not_active Withdrawn
-
2019
- 2019-11-08 EP EP19801322.9A patent/EP3903088A1/fr not_active Withdrawn
- 2019-11-08 WO PCT/EP2019/080667 patent/WO2020135943A1/fr unknown
Also Published As
Publication number | Publication date |
---|---|
WO2020135943A1 (fr) | 2020-07-02 |
DE102018251790A1 (de) | 2020-07-02 |
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