JP6411951B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine.

  In order to meet recent automobile fuel efficiency regulations and exhaust gas regulations, improvements in fuel efficiency and exhaust emissions are required. In order to improve the fuel efficiency and exhaust emissions, it is essential to suppress the deterioration of the combustion state of the engine and improve the combustion stability. And in order to improve the combustion stability of an engine, it is necessary to adjust appropriately the ignition energy supplied from an ignition device according to the composition and combustion state of the cylinder gas to burn.

  As a conventional technique for adjusting the ignition energy as described above, in Patent Document 1, in-cylinder in each cycle based on a predetermined frequency component extracted from a discharge voltage in at least a part of a discharge period leading to ignition. Estimate the turbulence intensity index value indicating the turbulence intensity of the gas and the turbulent combustion speed that is the combustion speed in the turbulent state of the gas mixture in the cylinder, and depending on the turbulence intensity index value and the turbulent combustion speed A technique for adjusting the ignition energy supplied to the spark plug during the combustion period in the cycle has been proposed.

International Publication No. 2014/085504

  In the prior art described in Patent Document 1, the ignition energy supplied to the ignition plug is calculated based on the turbulence intensity index value of the in-cylinder gas and the turbulent combustion speed estimated based on the predetermined frequency component extracted from the discharge voltage. By adjusting, combustion fluctuations between cycles are suppressed.

  Incidentally, the ignition energy required for stable combustion changes depending on the intake humidity. If the intake air humidity is high, it is necessary to increase the ignition energy supplied from the ignition device. Conversely, if the intake air humidity is low, the ignition energy supplied from the ignition device may be small.

  However, in the prior art described in Patent Document 1, it is not considered to adjust the ignition energy supplied from the ignition device in response to a change in ignition energy necessary for stable combustion caused by intake air humidity. For this reason, there is a possibility that deterioration of the combustion state, fuel consumption, and the like may occur due to excessive and insufficient ignition energy due to the intake humidity.

  The present invention has been made in view of the above-described problems, and the object of the present invention is to suppress deterioration of the combustion state and realize improvement in fuel consumption and exhaust emission even if the intake humidity changes. An object of the present invention is to provide a control device for an internal combustion engine that can perform the above-described operation.

  In order to solve the above-described problems, a control device for an internal combustion engine according to the present invention includes an ignition device that ignites an air-fuel mixture supplied to a combustion chamber, and a humidity detection unit that detects the humidity of intake air constituting the air-fuel mixture And controlling the ignition energy of the ignition device based on the humidity of the intake air.

  According to the present invention, by adjusting the ignition energy of the ignition device based on the intake humidity obtained by the humidity detection unit that detects the humidity of the intake air, the deterioration of the combustion state due to excess or shortage of ignition energy is suppressed, It is possible to improve fuel efficiency and exhaust emissions.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

1 is a system configuration diagram showing the configuration of an internal combustion engine to which a first embodiment of an internal combustion engine control device (ECU) according to the present invention is applied. The system block diagram which shows the internal structure of ECU shown in FIG. The block diagram which shows roughly the internal structure of ECU shown in FIG. The figure which shows an example of the relationship between the electricity supply time to the ignition device calculated by the electricity supply time calculation part shown in FIG. 3, and the intake air humidity detected by the humidity sensor. The block diagram which shows schematically the internal structure of 2nd Embodiment of the control apparatus (ECU) of the internal combustion engine which concerns on this invention. The figure which shows an example of the relationship between the frequency | count of ignition of the ignition device in one combustion stroke calculated by the ignition frequency | count calculation part shown in FIG. 5, and the intake air humidity detected by the humidity sensor. The block diagram which shows schematically the internal structure of 3rd Embodiment of the control apparatus (ECU) of the internal combustion engine which concerns on this invention. The time chart which each demonstrated the behavior of the primary current of the ignition coil, the secondary voltage, and the secondary current in the control processing by ECU shown in FIG. The figure which shows an example of the relationship between the discharge time of the ignition device calculated by the overlap discharge unit shown in FIG. 7, and the intake humidity detected by the humidity sensor. The system block diagram which shows the other examples of the internal combustion engine to which 1st-3rd embodiment of the control apparatus (ECU) of the internal combustion engine which concerns on this invention is applied.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a control device for an internal combustion engine according to the present invention will be described with reference to the drawings.

[First Embodiment]
First, with reference to FIGS. 1-4, 1st Embodiment of the control apparatus of the internal combustion engine which concerns on this invention is described.

  FIG. 1 is a system configuration diagram showing the configuration of an internal combustion engine (engine) to which a first embodiment of an internal combustion engine control device (ECU) according to the present invention is applied.

  The engine 100 of the illustrated embodiment is an automobile gasoline engine that performs spark ignition combustion, and includes an airflow sensor 1 that measures the amount of intake air and a humidity sensor (humidity detection) that detects intake humidity (humidity of intake air). 3) and an electronic control throttle 2 for adjusting the intake pipe pressure are provided at appropriate positions of the intake pipe 13 for introducing the intake air into the combustion chamber 4. The humidity sensor 3 is a sensor capable of detecting relative humidity or absolute humidity. The humidity sensor 3 may be a sensor that directly measures the intake humidity, or may be a sensor that detects a predetermined physical quantity and estimates the intake humidity. Further, it is desirable that the humidity sensor 3 is set at a position where the amount of water supplied to the combustion chamber 4 can be obtained with high accuracy according to the system.

  The engine 100 also includes a fuel injection device 8 that injects fuel into the cylinder 9 (combustion chamber 4) of each cylinder, and an ignition device that supplies ignition energy to ignite the air-fuel mixture supplied to the combustion chamber 4. 11 is provided for each cylinder. Although not shown, a high pressure fuel pump for supplying high pressure fuel to the fuel injection device 8 is connected to the fuel injection device 8 by a fuel pipe, and a fuel for measuring the fuel injection pressure in the fuel pipe. A pressure sensor is provided.

  Further, a three-way catalyst 6 for purifying exhaust and an air-fuel ratio detector, which is an air-fuel ratio sensor 5 that detects the air-fuel ratio of exhaust on the upstream side of the three-way catalyst 6, etc. Provided in position.

  Further, an accelerator opening sensor 7 for detecting the depression amount of the accelerator pedal, that is, an accelerator opening, and a battery voltage sensor 12 for measuring the battery voltage are provided at appropriate positions, although not shown, Is provided with a crank angle sensor for calculating a rotation angle.

  Signals obtained from the air flow sensor 1, the humidity sensor 3, the air-fuel ratio sensor 5, the accelerator opening sensor 7, the battery voltage sensor 12, and the like are sent to an ECU (engine control unit) 20 that is a control device.

  The ECU 20 calculates the energization time of the ignition device 11 based on the output signal of the battery voltage sensor 12. Further, the ECU 20 calculates a required torque based on the output signal of the accelerator opening sensor 7. That is, accelerator opening sensor 7 is used as a required torque detection sensor that detects a required torque for engine 100. ECU 20 calculates the rotational speed of engine 100 based on an output signal of a crank angle sensor (not shown). Further, the ECU 20 optimally calculates main operating amounts of the engine 100 such as an air flow rate, a fuel injection amount, an ignition timing, and a fuel pressure based on the operating state of the engine 100 obtained from the output signals of the various sensors.

  The fuel injection amount calculated by the ECU 20 is converted into a valve opening pulse signal and sent to the fuel injection device 8. Further, an ignition signal is sent to the ignition device 11 so as to be ignited at the ignition timing calculated by the ECU 20. The throttle opening calculated by the ECU 20 is sent to the electronic control throttle 2 as a throttle drive signal.

  Fuel is injected from the fuel injection device 8 into the air flowing into the cylinder 9 from the intake pipe 13 through the intake valve, and an air-fuel mixture is formed. This air-fuel mixture explodes by a spark generated from the ignition device 11 at a predetermined ignition timing, and the piston is pushed down by the combustion pressure to become a driving force of the engine 100. Further, the exhaust gas after the explosion is sent to the three-way catalyst 6 through the exhaust pipe 10, and the exhaust components are purified in the three-way catalyst 6 and discharged to the outside.

  FIG. 2 is a system block diagram showing an internal configuration of ECU 20 shown in FIG. The ECU 20 mainly includes an input circuit 20a, an input / output port 20b, a RAM 20c, a ROM 20d, and a CPU 20e, and an ignition device drive circuit 20f that generates a drive signal for driving the ignition device 11.

  Output signals of the air flow sensor 1, the humidity sensor 3, the air-fuel ratio sensor 5, the accelerator opening sensor 7, and the battery voltage sensor 12 are input to the input circuit 20a of the ECU 20. However, the input signal is not limited to these. The input signal of each input sensor is sent to the input port in the input / output port 20b. The signal sent to the input / output port 20b is stored in the RAM 20c and is processed by the CPU 20e. A control program describing the contents of the arithmetic processing is written in advance in the ROM 20d.

  A value indicating the operation amount of each actuator calculated in accordance with the control program is stored in the RAM 20c, then sent to the output port in the input / output port 20b, and sent to each actuator via each drive circuit. It is sent to an ignition device drive circuit (hereinafter also referred to as an ignition control unit) 20f that controls the ignition device 11.

  FIG. 3 is a block diagram schematically showing an internal configuration of the ECU 20 shown in FIG. 1, and is a diagram showing an outline of a block for controlling the ignition device 11 implemented in the ECU 20. The ECU 20 in the illustrated embodiment mainly includes an energization time calculation unit 31 and an ignition control unit 32 including the ignition device drive circuit 20f. The energization time calculation unit 31 includes an energization time basic value calculation unit 33 and And an energization time correction value calculation unit 34.

  The energization time calculation unit 31 calculates the energization time to the ignition device 11 in one combustion stroke from the battery voltage information measured by the battery voltage sensor 12 and the intake humidity information detected by the humidity sensor 3, and the calculation result Is sent to the ignition control unit 32.

  Specifically, the energization time basic value calculation unit 33 calculates the energization time basic value that is the base of the energization time based on the battery voltage information. Here, the lower the battery voltage is, the smaller the ignition energy supplied from the ignition device 11 is, so that the energization time basic value is increased. Further, the energization time correction value calculation unit 34 calculates an energization time correction value (correction amount of the energization time to the ignition device 11) for correcting the energization time basic value based on the intake humidity information. Here, since the energization time necessary for stable combustion becomes longer as the intake air humidity is higher, the energization time correction value is calculated to be larger. Then, the energization time correction value is added to or integrated with the energization time basic value to calculate the energization time that is the output of the energization time calculation unit 31. By such a calculation, the energization time to the ignition device 11 calculated by the energization time calculation unit 31 becomes longer as the battery voltage is lower and the intake humidity is higher. In other words, the energization time to the ignition device 11 calculated by the energization time calculation unit 31 can be shortened as the battery voltage is higher and the intake humidity is lower.

  In this embodiment, the energization time that is the output of the energization time calculation unit 31 is calculated by adding or integrating the energization time correction value to the energization time basic value, but is set in advance. You may make it acquire a value from a map.

  The ignition control unit 32 calculates the ignition timing from the ignition device 11 in one combustion stroke, and based on the ignition timing and the energization time output from the energization time calculation unit 31, the energization start timing to the ignition device 11 The energization end time is calculated.

  Supplying from the ignition device 11 in the combustion stroke is started by controlling the ignition device 11 to start energization to the ignition device 11 at the energization start timing and end energization to the ignition device 11 at the energization end timing. Adjust the ignition energy.

  In this embodiment, the battery voltage information and the intake humidity information are input to the energization time calculation unit 31, but the input to the energization time calculation unit 31 is not limited to this, and other information is input. You may make it input.

  FIG. 4 is a diagram showing an example of the relationship between the energization time (also referred to as the set energization time) to the ignition device 11 calculated by the energization time calculator 31 shown in FIG. 3 and the intake air humidity detected by the humidity sensor 3. It is. As already described, the ECU 20 according to the present embodiment is stable by adjusting the set energization time based on the intake air humidity detected by the humidity sensor 3 and adjusting the ignition energy supplied from the ignition device 11. Supply ignition energy required for combustion.

As shown in FIG. 4, in the prior art in which the energization time to the ignition device 11 is set without considering the intake humidity, when stable combustion is performed regardless of the intake humidity, the intake humidity is maximum (h _max ). Therefore, it is necessary to set the set energization time to Te (h _max ).

On the other hand, in the ECU 20 according to the present embodiment, the set energization time is set to Te (h _max ) when the intake humidity is maximum (h _max ), but the set energization is set when the intake humidity is h ₁ (h ₁ <h _max ). In order to set the time to Te (h ₁ ) (Te (h ₁ ) <Te (h _max )), when the intake air humidity is h ₁ , the set energization time is set to Te (h _max ) − as compared with the prior art. It can be shortened by Te (h ₁ ).

  Thereby, even if the intake humidity changes, it is possible to improve fuel consumption and exhaust emission without deteriorating the combustion state.

[Second Embodiment]
Next, a second embodiment of the control apparatus for an internal combustion engine according to the present invention will be described with reference to FIGS. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 5 is a block diagram schematically showing the internal configuration of the second embodiment of the control apparatus (ECU) for the internal combustion engine according to the present invention, and an outline of the block for controlling the ignition device 11 implemented in the ECU 20. FIG. The ECU 20 in the illustrated embodiment mainly includes an energization time calculation unit 51, an ignition control unit 52, and an ignition frequency calculation unit 53.

  The energization time calculation unit 51 calculates the energization time to the ignition device 11 in one combustion stroke from the battery voltage information measured by the battery voltage sensor 12, and sends the calculation result to the ignition control unit 52. Here, since the ignition energy supplied from the ignition device 11 is smaller as the battery voltage is lower, the energization time is calculated to be longer.

  The ignition frequency calculation unit 53 calculates the ignition frequency of the ignition device 11 in one combustion stroke based on the intake air humidity detected by the humidity sensor 3. Here, the higher the intake humidity, the lower the combustion stability, so that the number of ignitions of the ignition device 11 in one combustion stroke is increased. In other words, the calculation is performed such that the lower the intake air humidity, the less the number of ignitions of the ignition device 11 in one combustion stroke.

  The ignition control unit 52 calculates the ignition timing from the ignition device 11 in one combustion stroke, the ignition timing, the energization time output from the energization time calculation unit 51, and the ignition output from the ignition frequency calculation unit 53. Based on the number of times, an energization start timing and an energization end timing for the ignition device 11 are calculated for the number of ignitions in the combustion stroke. The ignition control unit 52 may set the energization time output from the energization time calculation unit 51 by the number of times of ignition output from the ignition frequency calculation unit 53, or the energization time output from the energization time calculation unit 51. The time may be divided and set by the number of ignitions output from the ignition frequency calculation unit 53.

  Supplying from the ignition device 11 in the combustion stroke is started by controlling the ignition device 11 to start energization to the ignition device 11 at the energization start timing and end energization to the ignition device 11 at the energization end timing. Adjust the ignition energy.

  In this embodiment, the battery voltage information is input to the energization time calculation unit 51. However, the input to the energization time calculation unit 51 is not limited to this, and other information is input. May be.

  FIG. 6 shows an example of the relationship between the number of ignitions of the ignition device 11 (also referred to as the set number of ignitions) in one combustion stroke calculated by the ignition frequency calculation unit 53 shown in FIG. 5 and the intake air humidity detected by the humidity sensor 3. FIG. As already described, the ECU 20 according to the present embodiment adjusts the number of ignitions based on the intake air humidity detected by the humidity sensor 3 and adjusts the ignition energy supplied from the ignition device 11, thereby stabilizing combustion. The ignition energy required for the is supplied.

The threshold value of the intake air humidity and h _2, the number of ignitions of igniter 11 in an combustion stroke which can ensure stable combustion, once when the intake humidity is less than h _2, when the intake humidity is h ₂ above 2 Times. In the prior art, the number of ignitions is fixed to 1 or 2 without considering the intake humidity. For example, by fixing the number of ignitions to 1, the combustion stability is low when the intake humidity is high. Or by fixing the number of ignitions to 2 times, when the intake air humidity is low, excessive ignition energy is supplied and fuel consumption deteriorates.

On the other hand, in the ECU 20 according to the present embodiment, the threshold value h ₂ of the intake humidity is set according to the above conditions, and when the intake humidity is less than h ₂ , the ignition device 11 is ignited once in one combustion stroke, When the intake humidity is equal to or higher than h _2, the ignition device 11 is ignited twice in one combustion stroke.

  Thereby, even if the intake humidity changes, it is possible to improve fuel consumption and exhaust emission without deteriorating the combustion state.

  In the above embodiment, the number of ignitions of the ignition device 11 in one combustion stroke is set to one or two. However, in the system in which the upper limit of the number of ignitions of the ignition device 11 in one combustion stroke is n times (n> 2). May set the number of ignitions in a range of 0 to n times.

[Third Embodiment]
Next, a third embodiment of the control apparatus for an internal combustion engine according to the present invention will be described with reference to FIGS. Note that in the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 7 is a block diagram schematically showing an internal configuration of the third embodiment of the control apparatus (ECU) for the internal combustion engine according to the present invention, and an outline of a block for controlling the ignition device 11 implemented in the ECU 20. FIG. The ECU 20 of the illustrated embodiment mainly includes an energization time calculation unit 71 and an ignition control unit 72, and an overlap discharge unit that includes a cylinder switching circuit 74, an overlap time control circuit 75, and a booster circuit 76. 73 is connected.

  Here, the ignition device 11 applies high voltage current from the booster circuit 76 to the secondary coil of the ignition coil 11b so as to improve ignitability and perform stable combustion. That is, by interrupting the primary current flowing through the primary coil of the ignition coil 11b, a high voltage of several kV generated in the secondary coil causes discharge breakdown in the discharge gap of the spark plug, and the secondary coil of the ignition coil 11b After the discharge current starts to flow, the DC-DC converter maintains the direct current voltage (usually about 500 V or more) higher than the discharge maintenance voltage value capable of maintaining this discharge state, while the output current from the DC-DC converter is changed to the ignition coil. It is superimposed on the discharge current in addition.

  As shown in FIG. 7, the ignition control unit 72 of the ECU 20 outputs an ignition control signal for the cylinders via a signal line 77 and outputs an overlap request signal via a signal line 78. The overlap discharge unit 73 is provided in an engine room or the like separately from the ECU 20, the booster circuit 76 and the secondary coil of each ignition coil 11b are connected by a high voltage line 79, and a high voltage of about 500V is applied to the secondary coil. To be applied. When the igniter 11 a provided in each ignition coil 11 b is switched to start discharge at a normal ignition timing for the cylinder to be ignited, the high voltage necessary to maintain the discharge state via the high-voltage line 79. A current is supplied to the secondary coil. In the combustion chamber 4, the spark plug is spark-discharged to ignite the air-fuel mixture, and so-called overlap discharge is performed following this normal discharge.

  The cylinder switching circuit 74 of the overlap discharge unit 73 determines the ignition timing of each cylinder based on the ignition control signal output from the ignition control unit 72, and the overlap time control circuit 75 is the overlap control output from the ignition control unit 72. The overlap discharge time required for the overlap discharge is controlled based on the request signal. The above-described overlap discharge is performed by supplying a high-voltage current necessary for the overlap discharge to the secondary coil of the ignition coil 11b corresponding to each cylinder in accordance with the input signal of the ignition control signal and the overlap request signal for each cylinder. be able to.

  FIG. 8 is a time chart for explaining the behavior of the primary current, secondary voltage, and secondary current of the ignition coil 11b in the control process by the ECU 20 shown in FIG.

  At time t1 when the output from the ignition control signal is turned on, the primary current starts to flow through the ignition coil 11b by switching of the igniter 11a. Then, when the primary current of the ignition coil 11b is cut off at the subsequent time t2, a high voltage is generated on the secondary coil side, and discharge is started at the ignition plug. Also, upon receiving the input information of the overlap request signal, the overlap time control circuit 75 determines the time for executing the overlap discharge. Further, the cylinder switching circuit 74 that determines the ignition timing of the target cylinder determines the target cylinder that is to be boosted by the booster circuit 76 based on the ignition control signal. Then, in conjunction with the time t3 before the time t2 when the primary current is cut off, a high-voltage current necessary for the overlap discharge is passed through the secondary coil of the ignition coil 11b of the target cylinder, and cooperates with the control circuit of the igniter 11a. And overlapping discharge is generated.

  Then, the overlap time control circuit 75 cuts off the flow of the high-voltage current from the booster circuit 76 and ends the overlap discharge at time t4 when the overlap discharge ends.

  In the present embodiment, the ignition control unit 72 of the ECU 20 acquires a value from the table of the overlapped discharge time tw with respect to the intake humidity set in advance based on the intake humidity information detected by the humidity sensor 3. The discharge time of the ignition device 11 in one combustion stroke is corrected by adjusting the overlap request signal. As described in the first embodiment, the higher the intake air humidity, the longer the discharge time required for stable combustion. Therefore, the discharge time is corrected to be longer. Conversely, the discharge time is corrected to be shorter as the intake air humidity is lower.

  FIG. 9 is a diagram illustrating an example of the relationship between the discharge time (also referred to as set discharge time) of the ignition device calculated by the overlapping discharge unit 73 shown in FIG. 7 and the intake air humidity detected by the humidity sensor 3. As already described, the ECU 20 according to the present embodiment adjusts the overlap request signal based on the intake air humidity detected by the humidity sensor 3, adjusts the set discharge time of the ignition device 11, and supplies it from the ignition device 11. By adjusting the ignition energy to be supplied, the ignition energy required for stable combustion is supplied.

Similar to the first embodiment, in the present embodiment, the intake humidity is h in comparison with the conventional technique in which the set discharge time is set to Td (h _max ) so that stable combustion is performed regardless of the intake humidity. _{Since the} set discharge time at ₃ (h ₃ <h _max ) is set to Td (h ₃ ) (Td (h ₃ ) <Td (h _max )), the set discharge time is set to Td (h _max ) −Td (h ₃ ) It can be shortened only.

  As a result, as in the first and second embodiments, even if the intake humidity changes, fuel consumption and exhaust emission can be improved without deteriorating the combustion state.

  In the first to third embodiments described above, the case where one ignition device 11 is provided for the combustion chamber 4 has been described (particularly, refer to FIG. 1), but as shown in FIG. A plurality of (two in the illustrated example) ignition devices 11, 11 </ b> A of the same type or different types may be provided for the chamber 4. Various ignition devices such as an ignition device that performs spark ignition and an ignition device that performs plasma jet ignition can be adopted as the separately provided ignition device 11A. In this case, the ECU 20 calculates the energization time and the ignition timing of both the ignition devices 11 and 11A, and sends an ignition signal to each of them. The intake humidity information detected by the humidity sensor 3 for both the ignition devices 11 and 11A The ignition energy may be corrected (controlled) based on the above, or the ignition energy may be corrected (controlled) based on the intake humidity information detected by the humidity sensor 3 for one of the ignition devices (specifically) (Refer to the first to third embodiments for a typical correction method).

  The present invention is not limited to the first to third embodiments described above, and includes various modifications. For example, the first to third embodiments described above have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. Moreover, it is possible to add / delete / replace other configurations for a part of the configurations of the embodiments.

  Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

DESCRIPTION OF SYMBOLS 1 ... Air flow sensor 2 ... Electronically controlled throttle 3 ... Humidity sensor (humidity detection part)
4 ... Combustion chamber 5 ... Air-fuel ratio sensor 6 ... Three-way catalyst 7 ... Accelerator opening sensor 8 ... Fuel injection device 9 ... Cylinder 10 ... Exhaust pipe 11 ... Ignition device 12 ... Battery voltage sensor 13 ... Intake pipe 20 ... ECU (control) apparatus)
20a ... input circuit 20b ... input / output port 20c ... RAM
20d ... ROM
20e ... CPU
20f ... ignition device drive circuit 31, 51, 71 ... energization time calculation unit 32, 52, 72 ... ignition control unit 33 ... energization time basic value calculation unit 34 ... energization time correction value calculation unit 53 ... ignition frequency calculation unit 73 ... overlap Discharge unit 74 ... Cylinder switching circuit 75 ... Overlap time control circuit 76 ... Boosting circuit 77, 78 ... Signal line 79 ... High pressure line 100 ... Engine (internal combustion engine)

Claims (3)

A control device for an internal combustion engine, comprising: an ignition device that ignites an air-fuel mixture supplied to a combustion chamber; and a humidity detector that detects the humidity of intake air constituting the air-fuel mixture,
A CPU for controlling the ignition energy of the ignition device by increasing the energization time to the ignition device as the battery voltage becomes lower;
The CPU reduces the number of ignitions of the ignition device so as to shorten the energization time to the ignition device in one combustion stroke as the humidity of the intake air detected by the humidity detection unit decreases, or by correcting to shorten the discharge time of the ignition device, the control device of the combustion engine within which controls the ignition energy of the ignition device.   2. The control device for an internal combustion engine according to claim 1, wherein a plurality of ignition devices are provided for one combustion chamber. The control device for an internal combustion engine according to claim 2 , wherein at least one ignition energy of the plurality of ignition devices is controlled.

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