Abstract: Self-diagnosis of a particle sensor may be used for determining a particle content in a gaseous stream. The particle sensor may include at least two interlocking, interdigital electrodes and a heating element. The heating element may be separated from the electrodes by an insulation layer. The particle sensor may be heated in a regeneration phase and a soot load on the particle sensor can thereby be removed. A semiconductive layer may be formed in the insulation layer directly beneath the electrodes by means of external doping or auto-doping. To perform a self-diagnosis, a measurement voltage may be applied at least periodically between the electrodes and a self-diagnostic current may be measured.

Abstract: A method for operating a particle sensor (10). The particle sensor (10) has at least two inter-digital electrodes (12, 13) which engage one in the other and to which a sensor voltage U(IDE) (21) is applied in order to determine loading of the particle sensor (10) with soot particles (16). A sensor current I(IDE) (31) across the electrodes (12, 13) is measured and evaluated. In order to remove the loading with soot, a heating element (14) heats the particle sensor (10) in a regeneration phase. The method characterized in that the sensor current I(IDE) (31) is determined, and a shunt diagnosis of the particle sensor (10) is carried out in accordance with the measured sensor current I(IDE) (31).

Abstract: A sensor element for determining a gas component or particles in a measuring gas, having a first and a second measuring electrode, the measuring electrodes being developed as interdigital electrodes having a row of intermeshing branches as well as a main conductor each, to which the branches are connected in an electrically conducting manner; and the branches of the interdigital electrodes being aligned essentially in parallel to a longitudinal axis of the sensor element.

Abstract: In a method for detecting a level of contamination of a particle sensor provided with two electrodes situated on an insulator material for generating an electrical field, the insulator material is heated to above a limiting temperature of the insulator material at which the insulator material begins to become conductive. The insulator material is modulated by heating or cooling, the modulation being carried out at a lower temperature and an upper temperature which are each above the limiting temperature. The variation over time of a measuring signal which may be picked up between electrodes is measured during the modulation. The measured variation over time of the measuring signal is compensated using a theoretical variation over time of the measuring signal in a contamination-free state of the particle sensor in order to obtain a variation over time of a differential signal.

Abstract: The invention relates to a method for diagnosing a particle filter used for filtering particles out of the exhaust gas of an internal combustion engine, wherein a collecting particle sensor is disposed downstream of the particle filter in the direction of flow of the exhaust gas and wherein a measurement for the loading of the particle sensor is determined from an output signal of the particle sensor.

Abstract: A method and a particle sensor (5) are provided for measuring particles, especially soot particles. The particles to be detected accumulate in a measuring region (10) of the particle sensor (5). The particles located in the gas stream (55) or the particles already accumulated in the measuring region (10) are burned by a combustion device (15), the combustion being controlled via a control signal from a control unit (20), which is electrically connected to a measuring device (25), in such a way that the quantity of the particles adhering in the measuring region (10) remains constant. The physical variable of the combustion device (15), which leads to the controlled combustion of the particles, is drawn upon as the signal amplitude of the particle sensor (5).

Abstract: The invention relates to a device used to measure exhaust gas having ionised particles in a motor vehicle. The device comprises an ionising device which includes an electrode arrangement and a charge measuring device. The electrode arrangement comprises at least one pair of electrodes including at least one electrode and at least one counter electrode. A dielectric is arranged between the electrode and the counter electrode in order to generate a dielectrically impeded discharge. The invention also relates to a corresponding method.

Abstract: A sensor element is provided for gas sensors, in particular to determine particles in gas mixtures, the sensor element including at least one electrochemical measuring element exposed to the gas mixture to be determined, and at least one temperature-measuring element integrated into the sensor element. The temperature-measuring element includes a resistor track, which has an electric resistance of less than 180 Ohm at 0° C. The resistor track may thus be produced by thin-foil technology, such as screen printing, for example.

Abstract: The invention concerns a procedure to ascertain a concentration of sooty particles in an exhaust gas system of an internal combustion engine or a depletion of an emission control system of the internal combustion engine due to the loading of sooty particles, whereby the sooty particle concentration in the exhaust gas system is determined by means of a collecting particle sensor, which emits a sensor signal and whereby the depletion of the emission control system due to the loading of sooty particles is determined from the sooty particle concentration. The task is thereby solved, in that the sensor signal is corrected by means of predetermined corrections with regard to a sensor temperature and/or an exhaust gas temperature and/or a flow velocity of the exhaust gas and/or a voltage applied at the particle sensor.

Abstract: A procedure for operating a collecting particle sensor, which is provided with measuring phases, during which particles that are contained in an off-gas stream accumulate on a measuring route, and a device for implementing this procedure are submitted. Protection phases are provided, during which at least one measure for diminishing the accumulation of particles on the measuring route is adopted. The measure according to this invention prevents a decrease of the sensitivity of the particle sensor over a long period of time.

Abstract: A method for operating a particle sensor (10). The particle sensor (10) has at least two inter-digital electrodes (12, 13) which engage one in the other and to which a sensor voltage U(IDE) (21) is applied in order to determine loading of the particle sensor (10) with soot particles (16). A sensor current I(IDE) (31) across the electrodes (12, 13) is measured and evaluated. In order to remove the loading with soot, a heating element (14) heats the particle sensor (10) in a regeneration phase. The method characterized in that the sensor current I(IDE) (31) is determined, and a shunt diagnosis of the particle sensor (10) is carried out in accordance with the measured sensor current I(IDE) (31).

Abstract: A method is described for controlling the soot deposition on sensors. A sensor element is provided, which includes a first electrode and a second electrode. Different measuring voltages U1 and U2 can be applied to the sensor element. During a first time period t1, the sensor element is operated at a higher voltage U1 until a triggering threshold AP of the sensor element is exceeded, while it is operated at a voltage U2, which is different from higher voltage U1, U2 being lower than voltage U1, during a second time period t2.

Abstract: A method and a particle sensor for measuring particles, especially soot particles, in which the particles to be detected accumulate in a measuring region of the particle sensor. The particles located in the gas stream or the particles already accumulated in the measuring region are burned by a combustion device, the combustion being controlled via a control signal from a control unit, which is electrically connected to a measuring device, in such a way that the quantity of the particles adhering in the measuring region remains constant. The physical variable of the combustion device, which leads to the controlled combustion of the particles, is drawn upon as the signal amplitude of the particle sensor.

Abstract: In a method and an apparatus for the defined regeneration of a sooty surface, in particular a ceramic sensor surface, in which the soot particles adhering to the surface are burned off by a dielectrically hindered discharge by of a discharge device, power of the dielectrically hindered discharge is set such that a higher rate of removal of the soot particles than their rate of deposition on the surface is effected, after the regeneration phase, the remaining soot deposit is detected by a measuring device mounted on the surface, wherein an undefined state of the sensor surface does not occur, and the discharge device and the measuring device may be mounted very compactly on one or two ceramic substrate elements.

Abstract: A sensor element for gas sensors for determining the concentration of particulates in gas mixtures, in particular soot sensors having at least one first measuring electrode applied to an electrically insulating substrate and at least one second measuring electrode, a voltage being applicable to the first and second measuring electrodes. The first measuring electrode is at least partly covered by a porous material open to diffusion of the particles to be determined.

Abstract: The invention relates to a method for the self-diagnosis of a particle sensor used for determining a particle content in a gaseous stream, wherein the particle sensor includes on its surface at least two interlocking, interdigital electrodes and a heating element separated from said electrodes by an insulation layer. Said particle sensor can be heated by said heating element in a regeneration phase, and a soot concentration can thereby be removed from the same. Provision is made according to the invention for a semiconductive layer to be formed in the insulation layer directly beneath the electrodes by means of external doping or auto-doping and in order to perform the self-diagnosis for a measurement voltage to be applied at least periodically between the electrodes and a self-diagnostic current to be measured.

Abstract: A sensor for determining the concentration of particles in gases, in particular of soot particles, has at least one substrate element, and a measuring area between at least one first and one second measuring electrode, the two measuring electrodes being configured so that by applying a voltage between the measuring electrodes, an asymmetric electric field is formed on the measuring area. The sides of the first and second measuring electrodes, facing one another, may not be parallel to one another, for example. Furthermore, at least one measuring electrode may have a structure along the side facing the other measuring electrode or along the finger electrodes.

Abstract: In a method for detecting a level of contamination of a particle sensor provided with two electrodes situated on an insulator material for generating an electrical field, the insulator material is heated to above a limiting temperature of the insulator material at which the insulator material begins to become conductive. The insulator material is modulated by heating or cooling, the modulation being carried out at a lower temperature and an upper temperature which are each above the limiting temperature. The variation over time of a measuring signal which may be picked up between electrodes is measured during the modulation. The measured variation over time of the measuring signal is compensated using a theoretical variation over time of the measuring signal in a contamination-free state of the particle sensor in order to obtain a variation over time of a differential signal.

Abstract: A sensor element for gas sensors for determining the concentration of particles in gas mixtures, especially soot sensors, having at least one measuring device exposed to the gas to be determined, at least one heating element integrated into the sensor element and at least one temperature measurement element integrated into the sensor element, the heating element being situated within the sensor element spatially between the measuring device and the temperature measurement element.

Abstract: The invention relates to a device used to measure exhaust gas having ionised particles in a motor vehicle. The device comprises an ionising device which includes an electrode arrangement and a charge measuring device. The electrode arrangement comprises at least one pair of electrodes including at least one electrode and at least one counter electrode. A dielectric is arranged between the electrode and the counter electrode in order to generate a dielectrically impeded discharge. The invention also relates to a corresponding method.