JP5691760B2 - Particulate matter treatment equipment - Google Patents

Description

  The present invention relates to a particulate matter processing apparatus.

  A technique is known in which a discharge electrode is provided in an exhaust passage of an internal combustion engine, and corona discharge is generated from the discharge electrode to charge particulate matter (hereinafter also referred to as PM) to agglomerate PM (for example, (See Patent Document 1). By aggregating PM, the number of PM particles can be reduced. Moreover, since the particle diameter of PM becomes large, when a filter is provided on the downstream side, PM is easily collected by the filter.

  Further, a technique is known in which when the current passing through the discharge electrode is equal to or greater than a predetermined value, it is determined that PM is attached to the discharge electrode, and the applied voltage is increased in order to remove PM from the discharge electrode ( For example, see Patent Document 2.) The removal of deposits from the electrode is called electrode regeneration.

  In addition, an insulator is provided between the electrode and the housing to which the electrode is attached, so that an electric current does not flow, and an average of a predetermined period when an inspection voltage about a fraction of the voltage for corona discharge is applied to the electrode A technique is known in which when the current is greater than or equal to a predetermined value, it is determined that PM adheres to the insulator and the insulation performance is degraded (see, for example, Patent Document 3).

  However, even if the applied voltage is lower than that at which corona discharge occurs, if it reaches a certain level, a current passes through a substance such as PM contained in the exhaust gas. For this reason, it is difficult to determine whether the detected current passes through the electrode deposits or the PM floating in the exhaust gas. Conventionally, the current passing through the PM floating in the exhaust gas has not been considered. Therefore, if it is determined whether to regenerate the electrode based on the current passing through the electrode, the determination accuracy may be lowered.

JP 2006-194116 A JP 2006-105081 A Japanese Patent Laid-Open No. 06-173635

  The present invention has been made in view of the above-described problems, and an object thereof is to optimize the timing of electrode regeneration.

In order to achieve the above object, the particulate matter processing apparatus according to the present invention is:
An electrode provided in an exhaust passage of the internal combustion engine;
A power source connected to the electrode for applying a voltage;
A detection device for detecting a current through the electrode;
A regenerator that regenerates the electrode, which is a process for removing deposits on the electrode;
An adhesion amount integrating device for estimating or detecting an integrated value of the amount of PM adhering to the electrode;
A removal amount integrating device for estimating an integrated value of the amount of PM removed from the electrode based on a current detected by the detection device during a fuel cut of the internal combustion engine;
When the value obtained by subtracting the integrated value of the PM amount obtained by the removal amount integrating device from the integrated value of the PM amount obtained by the adhesion amount integrating device is equal to or greater than a threshold value, the regeneration device regenerates the electrode. A reproduction time determination device to perform,
Is provided.

  Here, when voltage is applied to the electrodes, PM can be charged. The charged PM moves toward the inner wall of the exhaust passage due to the Coulomb force or the flow of exhaust. Since the PM that has reached the inner wall of the exhaust passage emits electrons to the exhaust passage, electricity flows to the ground side from the electrode. And since PM which emitted the electron aggregates with other PM which exists near, the number of particles can be decreased.

  By the way, when a substance such as PM or water adheres to the electrode, electricity easily flows between the electrode and the exhaust passage through the attached substance. That is, the insulating property of the electrode is lowered. As described above, when there are deposits on the electrode, when a voltage is applied to the electrode, PM may not be aggregated even though a current flows through the electrode. When a substance such as PM adheres to the electrode, it becomes difficult to charge the PM floating in the exhaust gas, so that it is difficult to aggregate the PM. Therefore, when deposits such as PM are present on the electrode, the electrode is regenerated as a process for removing the deposits from the electrode. The regeneration of the electrode is performed by a regeneration device.

  The regeneration device oxidizes or evaporates a substance attached to the electrode, for example, by increasing the temperature of the electrode. Further, the temperature of the electrode may be increased and the oxygen concentration in the exhaust gas may be increased. Moreover, you may heat an electrode.

  The regeneration time of the electrode is determined based on the amount of PM attached to the electrode and the amount of PM removed from the electrode. Here, the amount of PM adhering to the electrode is correlated with the number of PM particles in the exhaust. For this reason, if the number of PM particles in the exhaust gas is estimated from, for example, the operating state of the internal combustion engine or detected by a sensor, the amount of PM adhering to the electrode can be obtained. Then, by integrating the amount of PM attached to the electrode, the total amount of PM attached to the electrode in the past can be obtained.

  On the other hand, the amount of PM removed from the electrode can be estimated based on the current detected during the fuel cut. Here, if fuel cut is performed in a state where PM is attached to the electrode, exhaust gas having a high oxygen concentration passes around the electrode. In addition, since a voltage is applied to the electrode, the temperature of the electrode is high. Accordingly, since the temperature is high and the oxygen concentration is high around the electrode, the PM adhering to the electrode is oxidized and removed. Thus, when PM is oxidized, the detected current increases because of the movement of electrons. For this reason, the amount of PM removed from the electrode is correlated with the detected current. Therefore, the amount of PM removed from the electrode can be obtained based on the current detected during the fuel cut. And the total amount of PM removed from the electrode can be obtained by integrating the amount of PM removed from the electrode.

  Further, by subtracting the total amount of PM removed from the electrode from the total amount of PM adhering to the electrode, the amount of PM remaining on the electrode at that time can be obtained. If the amount of PM remaining on the electrode at that time is equal to or greater than the threshold value, the electrode is regenerated. This threshold value can be the amount of adhesion of PM that requires electrode regeneration. In this way, it is possible to optimize the electrode regeneration timing.

Further, in the present invention, a processing unit provided in the exhaust passage and provided with the electrode;
An insulating part for insulating electricity between the processing part and the exhaust passage;
A grounding unit for grounding the processing unit;
With
The detection device can detect a current at the grounding portion.

  In this case, the detection device detects a current on the potential reference point side of the electrode. Generally, on the power supply side from the electrode, the wiring is longer or thicker than the electrode on the ground side. In addition, charges may be stored on the power supply side of the electrode. Then, if the current is detected on the power supply side with respect to the electrode, the current detected by the detection device rises and falls slowly. On the other hand, on the ground side from the electrode, the wiring can be made relatively short and thin. For this reason, an electric current can be detected more correctly. Moreover, it can suppress that electricity flows other than a grounding part by providing an insulating part. For this reason, an electric current can be detected more correctly.

  In the present invention, the removal amount integrating device calculates the amount of PM removed from the electrode based on a value obtained by integrating the current detected by the detection device during a fuel cut of the internal combustion engine, Can be accumulated.

  That is, the larger the current is, the more PM is removed, and the longer the current is, the more PM is removed. Therefore, the value obtained by integrating the current over time is removed from the electrode. Correlation with the amount of PM. Therefore, the amount of PM removed from the electrode can be calculated based on this integral value.

  According to the present invention, it is possible to optimize the regeneration timing of the electrodes.

It is a figure which shows schematic structure of the particulate matter processing apparatus which concerns on an Example. It is a time chart which showed transition of current during fuel cut. It is the flowchart which showed the determination flow of the electrode regeneration time which concerns on an Example. It is the figure which showed an example of the map for calculating the number of PM particles from an engine speed and an engine load. It is the figure which showed an example of the map for calculating an applied voltage (V) from the amount (g / sec) of exhaust gas from an internal combustion engine, and the number of PM particle | grains (x10 < ⁵ > piece / cm < ³ >).

  Hereinafter, specific embodiments of the particulate matter processing apparatus according to the present invention will be described with reference to the drawings.

Example 1
FIG. 1 is a diagram illustrating a schematic configuration of a particulate matter processing apparatus 1 according to the present embodiment. The particulate matter processing apparatus 1 is provided in an exhaust passage 2 of a gasoline engine. It can also be provided in the exhaust passage of a diesel engine.

  The particulate matter processing apparatus 1 includes a housing 3 whose both ends are connected to an exhaust passage 2. The material of the housing 3 is a stainless steel material. The housing 3 is formed in a hollow cylindrical shape having a diameter larger than that of the exhaust passage 2. Both ends of the housing 3 are formed in a tapered shape in which the cross-sectional area decreases as the distance from the end increases. In FIG. 1, the exhaust flows through the exhaust passage 2 in the direction of the arrow and flows into the housing 3. For this reason, the housing 3 may be a part of the exhaust passage 2.

  The exhaust passage 2 and the housing 3 are connected via an insulating portion 4. The insulating part 4 is made of an electrical insulator. The insulating portion 4 is sandwiched between a flange 21 formed at the end of the exhaust passage 2 and a flange 31 formed at the end of the housing 3. The exhaust passage 2 and the housing 3 are fastened by bolts and nuts, for example. In addition, these bolts and nuts are also insulated so that electricity does not flow through these bolts and nuts. In this way, electricity is prevented from flowing between the exhaust passage 2 and the housing 3.

  An electrode 5 is attached to the housing 3. The electrode 5 penetrates the side surface of the housing 3, extends from the side surface of the housing 3 toward the central axis of the housing 3, bends in the vicinity of the central axis, and upstream of the flow of exhaust gas, and is parallel to the central axis It extends toward the upstream side of the exhaust flow. Further, it bends further to the side surface side of the housing 3 on the upstream side, passes through the side surface of the housing 3 and communicates with the outside.

  In order to prevent electricity from flowing between the electrode 5 and the housing 3, the electrode 5 is provided with insulator portions 51 and 55 made of an electrical insulator. The insulator portions 51 and 55 are located between the electrode 5 and the housing 3, and have a function of insulating electricity and fixing the electrode 5 to the housing 3.

  One end of the electrode 5 is connected to the power supply 6 via the power supply side electric wire 52. The power source 6 can energize the electrode 5 and change the applied voltage. The power source 6 is connected to the control device 7 and the battery 8 through electric wires. The control device 7 controls the voltage that the power source 6 applies to the electrode 5. The power supply 6 is connected to a ground wire 54 for connection to a potential reference point. The power source 6 is grounded by the ground wire 54.

  The other end of the electrode 5 is connected to the ground wire 54 via a short-circuit wire 56. A switch 57 for opening and closing the circuit is provided in the middle of the short-circuit wire 56. When the switch 57 is turned on while a voltage is applied by the power source 6, electricity flows through the short-circuited wire 56. At this time, since the electrode 5 is short-circuited, the temperature of the electrode 5 rises. In the present embodiment, the short-circuit wire 56 and the switch 57 correspond to the reproducing device in the present invention. Further, in this embodiment, the power source side electric wire 52 is connected to the downstream side insulator 51, and the short circuit wire 56 is connected to the upstream side insulator 55, but instead, the downstream side insulator 51 is connected. The short-circuited wire 56 may be connected to the power supply side electric wire 52 and the upstream side insulator portion 55 may be connected.

  A ground side electric wire 53 is connected to the housing 3, and the housing 3 is grounded via the ground side electric wire 53. The ground side electric wire 53 is provided with a detection device 9 that detects a current passing through the ground side electric wire 53. For example, the detection device 9 detects a current by measuring a potential difference between both ends of a resistor provided in the middle of the ground-side electric wire 53. The detection device 9 is connected to the control device 7 via an electric wire. Then, the current detected by the detection device 9 is input to the control device 7. In addition, since the electric capacity of the ground side electric wire 53 is smaller than that of the power source side electric wire 52, the response when detecting the current is higher when the detection device 9 is provided in the ground side electric wire 53. However, the detection device 9 may be provided in the power supply side electric wire 52 instead of the ground side electric wire 53.

  Note that an accelerator opening sensor 71, a crank position sensor 72, a temperature sensor 73, and an air flow meter 74 are connected to the control device 7. The accelerator opening sensor 71 outputs an electrical signal corresponding to the amount of depression of the accelerator pedal by the driver of the vehicle on which the internal combustion engine is mounted, and detects the engine load. The crank position sensor 72 detects the engine speed. The temperature sensor 73 detects the temperature of the internal combustion engine by detecting the temperature of the cooling water of the internal combustion engine or the temperature of the lubricating oil. The air flow meter 74 detects the intake air amount of the internal combustion engine.

  In addition, a switch 57 is connected to the control device 7 via an electric wire, and the control device 7 performs an ON-OFF operation of the switch 57. Here, when the voltage is applied from the power source 6 to the electrode 5, the current passes through the short-circuited wire 56 by turning on the switch. On the other hand, when the switch is turned off, no current flows through the short-circuited wire 56.

  In the particulate matter processing apparatus 1 configured in this way, electrons are emitted from the electrode 5 by applying a negative high DC voltage from the power source 6 to the electrode 5 when the switch 57 is OFF. That is, electrons are emitted from the electrode 5 by making the potential of the electrode 5 lower than that of the housing 3. The electrons in the exhaust gas can be negatively charged by the electrons. Negatively charged PM moves due to Coulomb force and gas flow. When the PM reaches the housing 3, the electrons that have negatively charged the PM are emitted to the housing 3. The PM that has released electrons to the housing 3 aggregates to increase the particle size. Moreover, the number of PM particles is reduced due to aggregation of PM. That is, by applying a voltage to the electrode 5, the particle diameter of PM can be increased and the number of PM particles can be reduced.

  By the way, when a substance such as PM or water adheres to the electrode 5 including the insulator portion 51, the insulating property of the electrode 5 is lowered. And electricity can flow between the electrode 5 and the housing 3 through these deposits. Then, since electrons emitted from the electrode 5 are reduced, it is difficult to charge the PM floating in the exhaust gas, and it is difficult to aggregate the PM. For this reason, the regeneration process of the electrode 5 is implemented.

  Here, the regeneration process of the electrode 5 is a process for removing deposits such as PM and water adhering to the electrode 5 including the insulator parts 51 and 55. In this embodiment, the electrode 5 is regenerated by applying a voltage from the power source 6 while turning on the switch 57. That is, by short-circuiting the electrode 5, the temperature of the electrode 5 is raised and the deposits are removed by burning or evaporation. In order to oxidize PM quickly, it is better that the oxygen concentration in the exhaust gas is high. Therefore, the oxygen concentration in the exhaust gas may be increased before the electrode 5 is short-circuited or when the electrode 5 is short-circuited. In order to increase the oxygen concentration in the exhaust gas, for example, in a hybrid vehicle including an internal combustion engine and a motor as a vehicle drive source, the crankshaft of the internal combustion engine may be rotated by the motor without supplying fuel to the internal combustion engine. Good. Thereby, since air can be discharged | emitted from an internal combustion engine, the oxygen concentration in exhaust_gas | exhaustion can be raised. Further, by temporarily increasing the engine speed before stopping the internal combustion engine and stopping the fuel supply when the engine speed is high, air can be discharged into the exhaust passage. Then, the electrode 5 may be short-circuited when the internal combustion engine stops thereafter. Further, at the time of fuel cut during the deceleration operation, the oxygen concentration in the exhaust gas becomes high. Therefore, the electrode 5 may be short-circuited at this time.

  The regeneration of the electrode 5 is performed when the amount of PM estimated to be attached to the electrode 5 becomes equal to or greater than a threshold value. That is, when the amount of PM adhering to the electrode 5 increases, the insulating property of the electrode 5 decreases, and it becomes difficult to aggregate the PM. Therefore, the electrode 5 is regenerated. The threshold value is a lower limit value of the PM amount that requires regeneration of the electrode 5. This may be a PM adhesion amount that makes aggregation of PM difficult. Further, the threshold value may be a value with a certain margin so that the regeneration of the electrode 5 is performed before the aggregation of PM is actually difficult.

The amount of PM adhering to the electrode 5 is calculated by subtracting the integrated value of the PM amount removed from the electrode 5 in the past from the integrated value of the PM amount adhering to the electrode 5 in the past. The amount of PM adhered to the electrode 5 in the past has a correlation with the number of PM particles (number / cm ³ ) discharged from the internal combustion engine. Therefore, by integrating the number of PM particles and multiplying the integrated value by a predetermined coefficient, it is possible to obtain an integrated value of the PM amount adhering to the electrode 5 in the past (hereinafter referred to as an attached PM integrated amount). it can. In addition, you may obtain | require the adhesion PM integrated amount by integrating | accumulating the value which multiplied the predetermined coefficient to the PM particle number.

  On the other hand, the integrated value of the PM amount removed from the electrode 5 in the past can be calculated based on the current detected by the detection device 9.

  Here, FIG. 2 is a time chart showing transition of current during fuel cut. The detection current is a current detected by the detection device 9. Further, the fuel cut of the internal combustion engine is performed during the period described as “in fuel cut” in FIG. 2. That is, the supply of fuel to the internal combustion engine is stopped. Note that the fuel cut can also be included when a small amount of fuel is supplied so that the engine speed does not decrease excessively.

As shown in FIG. 2, the detected current increases during the fuel cut. Here, since the oxygen concentration in the exhaust gas becomes high during the fuel cut, the PM adhering to the electrode 5 is oxidized. It is considered that the detection current increases due to the movement of electrons when PM is oxidized. For this reason, the amount of increase when the detection current increases and the duration during which the detection current increases correlate with the amount of PM removed from the electrode 5. Therefore, in this embodiment, the amount of PM removed from the electrode 5 is calculated based on the integrated value of the detected current. It is assumed that PM is removed from the electrode 5 when the detected current becomes equal to or greater than the predetermined value I0. The predetermined value I0 is obtained in advance by experiments or the like as the lower limit value of the current detected when PM is removed from the electrode 5. In FIG. 2, the detection current I (t1) is equal to or greater than the predetermined value I0 at the time t1, and the detection current I (t2) is equal to or less than the predetermined value I0 at the time t2. In FIG. 2, the integral value is obtained as an area of a portion that is equal to or smaller than the detection current I (t) and equal to or larger than the predetermined value I0. This corresponds to the area of the hatched portion in FIG. This area is defined as an energization area S. This energization area S can be obtained by the following equation.

  The energization area S obtained in this way is correlated with the amount of PM removed from the electrode 5. Therefore, the amount of PM removed from the electrode 5 per fuel cut can be calculated by multiplying the energization area S by a predetermined coefficient. By integrating the PM amount, an integrated value of the PM amount removed from the electrode 5 in the past (hereinafter referred to as a removed PM integrated amount) can be obtained. In addition, the removal PM integrated amount can be obtained by integrating the energized area S and multiplying the integrated value by a predetermined coefficient.

  Then, by subtracting the removed PM accumulated amount from the accumulated PM accumulated amount, the PM amount adhering to the electrode 5 at that time (hereinafter referred to as the residual PM amount) can be calculated. When the residual PM amount is equal to or greater than the threshold value, the electrode 5 is regenerated.

  Next, FIG. 3 is a flowchart showing a determination flow of electrode regeneration timing according to the present embodiment. This routine is repeatedly executed by the control device 7 every predetermined time.

In steps S101 to S103, the number of PM particles (pieces / cm ³ ) is calculated. The number of PM particles is the number of PM particles discharged from the internal combustion engine, and is the number of PM particles before flowing into the housing 3. Since the number of PM particles is correlated with the engine speed, the engine load, and the temperature of the internal combustion engine (for example, the temperature of the lubricating oil or the temperature of the cooling water), the number of PM particles is calculated based on these values.

For this reason, in step S101, the engine speed and the engine load are acquired. The engine speed is detected by a crank position sensor 72 and the engine load is determined by an accelerator opening sensor 7.
1 is detected. In step S102, the temperature of the internal combustion engine is acquired. The temperature of the internal combustion engine is detected by a temperature sensor 73.

  In step S103, the number of PM particles is calculated. Here, FIG. 4 is a diagram showing an example of a map for calculating the number of PM particles from the engine speed and the engine load. The control device 7 stores a plurality of this relationship according to the temperature of the internal combustion engine. Then, the number of PM particles is obtained from the engine speed and the engine load using a map corresponding to the detected temperature of the internal combustion engine. This map is obtained in advance by experiments or the like.

  A particle number sensor for detecting the number of PM particles in the exhaust gas may be provided in the exhaust passage 2 upstream of the housing 3, and the detection value of the particle number sensor may be used. This particle number sensor detects the number of PM particles per unit volume in the exhaust gas. The particle number sensor is connected to the control device 7 via an electric wire. The number of PM particles detected by the particle number sensor is input to the control device 7.

  In this embodiment, the control device 7 that processes step S103 corresponds to the particle number detection device of the present invention. Further, when the number of PM particles is detected by a particle number sensor, the particle number sensor corresponds to the particle number detection device in the present invention.

  In step S104, the applied voltage to the electrode 5 is calculated based on the number of PM particles calculated in step S103. This is an applied voltage for aggregating PM.

FIG. 5 is a diagram showing an example of a map for calculating the applied voltage (V) from the exhaust gas amount (g / sec) from the internal combustion engine and the number of PM particles (× 10 ⁵ particles / cm ³ ). is there. This map is obtained in advance by experiments or the like. Since the exhaust gas amount from the internal combustion engine is correlated with the intake air amount of the internal combustion engine, it can be obtained based on the intake air amount detected by the air flow meter 74.

  Here, since the inertia force of PM becomes smaller as the amount of exhaust gas is smaller, the influence of electrostatic action becomes relatively larger. For this reason, PM tends to aggregate. Therefore, as the amount of exhaust gas decreases, PM aggregates with a smaller applied voltage. For this reason, the applied voltage is reduced as the amount of exhaust gas decreases. Also, the greater the number of PM particles, the shorter the distance between the PM particles, so that the influence of electrostatic action becomes relatively large. For this reason, the PM aggregates with a smaller applied voltage as the number of PM particles increases. For this reason, the applied voltage is decreased as the number of PM particles is increased.

  The applied voltage may be a value such that the reduction rate of the number of PM particles becomes a predetermined value (for example, 40%). The applied voltage may be a predetermined value that is determined in advance. This specified value can be a value with a margin so that no pulse current is generated.

  Then, after the applied voltage is calculated, the process proceeds to step S105, and the current is acquired. This current is a value detected by the detection device 9. The applied voltage may be controlled based on this current.

  In step S106, the number of PM particles calculated in step S103 is integrated. In step S107, the accumulated amount of adhered PM is calculated based on the integrated value of the number of PM particles calculated in step S106. The accumulated amount of adhered PM is obtained by multiplying the accumulated value of the number of PM particles calculated in step S106 by a predetermined coefficient. This predetermined coefficient is obtained in advance by experiments or the like. In this embodiment, the control device 7 that processes step S107 corresponds to the adhesion amount integrating device in the present invention.

  In step S108, it is determined whether or not a fuel cut is in progress. That is, it is determined whether or not the PM adhering to the electrode 5 is in a state to be removed. If an affirmative determination is made in step S108, the process proceeds to step S109. If a negative determination is made, the removal PM integrated amount does not change, and the process proceeds to step S112.

  In step S109, the energization area S is calculated. That is, the energization area S, which is the hatched area in FIG. 2, is calculated by the above integral formula.

  In step S110, the removed PM amount is calculated. The removal PM amount is obtained by multiplying the energization area S calculated in step S109 by a predetermined coefficient. This predetermined coefficient is obtained in advance by experiments or the like.

  In step S111, the removal PM integrated amount is calculated. That is, the removed PM amount calculated in step S110 is integrated. In the present embodiment, the control device 7 that processes step S111 corresponds to the removal amount integrating device in the present invention.

  In step S112, the residual PM amount is calculated. That is, the removal PM integration amount calculated in step S111 is subtracted from the adhesion PM integration amount calculated in step S107.

  In step S113, it is determined whether the residual PM amount calculated in step S112 is greater than or equal to a threshold value. The threshold value here is obtained in advance by experiments or the like as the lower limit value of the residual PM amount that requires regeneration of the electrode 5. That is, in this step, it is determined whether or not the electrode 5 needs to be regenerated.

  If an affirmative determination is made in step S113, the process proceeds to step S114. If a negative determination is made, regeneration of the electrode 5 is not necessary, and thus this routine is terminated.

  In step S114, the electrode regeneration flag is turned ON. The electrode regeneration flag is a flag that is turned on when the electrode 5 needs to be regenerated and turned off when the electrode 5 is not regenerated. Note that the initial value of the electrode regeneration flag is OFF. When the electrode regeneration flag is turned ON, the regeneration process of the electrode 5 is performed in the operation state suitable for the regeneration of the electrode 5. In this embodiment, the control device 7 that processes step S113 and step S114 corresponds to the regeneration timing determination device in the present invention.

  In this manner, the amount of PM remaining on the electrode 5 can be estimated by calculating the amount of PM removed from the electrode 5 based on the current during fuel cut. Thereby, since the regeneration time of the electrode 5 can be optimized, the aggregation of PM can be promoted. Moreover, since it can suppress that regeneration of the electrode 5 is performed more than necessary, energy consumption can be reduced, so that deterioration of fuel consumption can be suppressed.

DESCRIPTION OF SYMBOLS 1 Particulate matter processing apparatus 2 Exhaust passage 3 Housing 4 Insulation part 5 Electrode 6 Power supply 7 Control apparatus 8 Battery 9 Detection apparatus 21 Flange 31 Flange 51 Insulator part 52 Power supply side electric wire 53 Ground side electric wire 54 Ground electric wire 55 Insulator part 56 Short circuit electric wire 57 Switch 71 Accelerator opening sensor 72 Crank position sensor 73 Temperature sensor 74 Air flow meter

Claims (3)

An electrode provided in an exhaust passage of the internal combustion engine;
A power source connected to the electrode for applying a voltage;
A detection device for detecting a current through the electrode;
A regenerator that regenerates the electrode, which is a process for removing deposits on the electrode;
An adhesion amount accumulating device that estimates or detects the number of particles of particulate matter in the exhaust gas of the internal combustion engine and obtains an accumulated value of the amount of PM adhering to the electrode based on the number of particles of the particulate matter ;
A removal amount integrating device for estimating an integrated value of the amount of PM removed from the electrode based on a current detected by the detection device during a fuel cut of the internal combustion engine;
When the value obtained by subtracting the integrated value of the PM amount obtained by the removal amount integrating device from the integrated value of the PM amount obtained by the adhesion amount integrating device is equal to or greater than a threshold value, the regeneration device regenerates the electrode. A reproduction time determination device to perform,
A particulate matter processing apparatus comprising: A processing section provided in the exhaust passage and provided with the electrode;
An insulating part for insulating electricity between the processing part and the exhaust passage;
A grounding unit for grounding the processing unit;
With
The particulate matter processing apparatus according to claim 1, wherein the detection device detects current at the grounding portion.   The removal amount integrating device calculates the amount of PM removed from the electrode based on a value obtained by integrating the current detected by the detection device during a fuel cut of the internal combustion engine, and integrates the amount of PM. The particulate matter processing apparatus according to claim 1 or 2.

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