Control system for hybrid vehicles

Abstract

The present invention provides a control device for a hybrid vehicle that can ensure opportunities for detecting differential pressure between the front and rear axles while suppressing an increase in fuel consumption. [Solution] The hybrid vehicle includes a control device, an internal combustion engine, an exhaust passage, a filter for collecting particulate matter contained in the exhaust, and a differential pressure sensor for detecting the front-to-rear differential pressure, which is the difference between the pressure upstream of the filter and the pressure downstream of the filter. The control device includes a processing circuit. The processing circuit performs differential pressure detection control, which repeatedly detects the front-to-rear differential pressure, provided that the front-to-rear differential pressure is greater than or equal to a first predetermined value. If the front-to-rear differential pressure falls below a second predetermined value which is greater than the first predetermined value during the execution of the differential pressure detection control, the processing circuit starts output boosting control, which increases the requested output to the internal combustion engine (step S21). The processing circuit performs defect determination control, which determines whether or not there is a defect in the filter using the multiple front-to-rear differential pressure data collected by the differential pressure detection control.

Description

Technical Field

[0004] , , , ,

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[0001] This invention relates to a control device for a hybrid vehicle.

Background Art

[0002] Patent Document 1 discloses a vehicle in which a collector for collecting fine particles in exhaust gas is installed in the middle of an exhaust passage. The collector incorporates a filter for collecting fine particles. The control device of the vehicle determines the presence or absence of a defect in the filter by detecting a differential pressure before and after, which is the difference in pressure between the upstream side and the downstream side of the collector, using a differential pressure sensor. The higher the exhaust pressure on the upstream side of the collector, the greater the difference between the differential pressure before and after when the filter is normal and the differential pressure before and after when the filter is defective. Therefore, when determining the presence or absence of a defect in the filter by detecting the differential pressure before and after, it is preferable that the exhaust pressure in the exhaust passage is high.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A hybrid vehicle can use the output of a motor as a driving force for the vehicle in addition to the output of an internal combustion engine. Therefore, hybrid vehicles tend to emit less exhaust gas generated during the operation of the internal combustion engine compared to vehicles equipped with only an internal combustion engine. In addition, hybrid vehicles tend to have fewer opportunities to operate the internal combustion engine compared to vehicles equipped with only an internal combustion engine.

[0005] Therefore, in hybrid vehicles, the period during which the exhaust pressure in the exhaust passage is at a pressure suitable for detecting the differential pressure across the front and rear of the filter, which is necessary to determine whether or not the filter is damaged, is short. As a result, hybrid vehicles may have fewer opportunities to detect the differential pressure across the front and rear of the filter, which is necessary to determine whether or not the filter is damaged. [Means for solving the problem]

[0006] The control device for a hybrid vehicle to solve the above problems is applied to a hybrid vehicle that includes an internal combustion engine and a motor generator as power sources to drive the drive shaft, a battery that charges the power generated by the motor generator using the output of the internal combustion engine, an exhaust passage that guides the exhaust from the internal combustion engine to the rear of the vehicle, a filter that collects particulate matter contained in the exhaust, and a differential pressure sensor that detects the front-to-rear differential pressure, which is the difference between the pressure upstream of the filter and the pressure downstream of the filter. The control device for the hybrid vehicle includes a processing circuit. The processing circuit performs differential pressure detection control, which repeatedly detects the front-to-rear differential pressure, on the condition that a value correlated with the exhaust pressure is greater than or equal to a first predetermined value. If, during the execution of the differential pressure detection control, the value correlated with the exhaust pressure falls below a second predetermined value which is greater than the first predetermined value, the processing circuit starts output boosting control, which increases the output requested from the internal combustion engine as a control to increase the output of the internal combustion engine and increase the amount of power generated by the motor generator. The processing circuit performs a defect determination control to determine whether or not there is a defect in the filter using a plurality of differential pressure data collected by the differential pressure detection control. [Effects of the Invention]

[0007] The control device for the hybrid vehicle described above can ensure the opportunity to detect the differential pressure between the front and rear axles while suppressing an increase in fuel consumption. [Brief explanation of the drawing]

[0008] [Figure 1]Figure 1 is a schematic diagram showing the configuration of a control device in one embodiment and a hybrid vehicle to which the control device is applied. [Figure 2] Figure 2 is a flowchart showing the sequence of processes that determine whether or not the processing circuit shown in Figure 1 performs differential pressure detection control. [Figure 3] Figure 3 is a flowchart showing the sequence of processes that determine whether or not the processing circuit shown in Figure 1 starts output boosting control. [Figure 4] Figure 4 is a flowchart showing the sequence of processes by which the processing circuit shown in Figure 1 determines whether or not to terminate the output boosting control. [Figure 5] Figure 5 is a flowchart showing the sequence of processes by which the processing circuit shown in Figure 1 manipulates the filter defect detection flag. [Modes for carrying out the invention]

[0009] Below, one embodiment of the control device for a hybrid vehicle will be described with reference to Figures 1 to 5. <Configuration of hybrid vehicle 1 to which control device 100 is applied> As shown in Figure 1, the control device 100 of this embodiment includes a processing circuit 101 that executes a program and performs various processes, and a storage device 102 in which the program is stored. The processing circuit 101 includes a processor. The storage device 102 is capable of storing various data. The hybrid vehicle 1 to which the control device 100 is applied is equipped with an internal combustion engine 10. The hybrid vehicle 1 is equipped with a first motor generator 71 and a second motor generator 72, which are two motor generators that combine the functions of both a motor and a generator. The hybrid vehicle 1 is equipped with a battery 77, a first inverter 75 and a second inverter 76. The battery 77 charges the power generated by the first motor generator 71 and the second motor generator 72 using the output of the internal combustion engine 10. The battery 77 supplies the stored power to the first motor generator 71 and the second motor generator 72 when they are functioning as motors. The first inverter 75 adjusts the amount of power exchanged between the first motor generator 71 and the battery 77. The second inverter 76 adjusts the amount of power exchanged between the second motor generator 72 and the battery 77.

[0010] The internal combustion engine 10 has multiple cylinders 11 for burning a fuel-air mixture. The internal combustion engine 10 is provided with an intake passage 15 that serves as an introduction path for air to the multiple cylinders 11. The intake passage 15 is equipped with a throttle valve 16, which is a valve for adjusting the amount of intake air. The portion of the intake passage 15 downstream of the throttle valve 16 branches out for each cylinder. Each of the cylinder-specific branches in the intake passage 15 is equipped with a fuel injection valve 17. Each of the multiple cylinders 11 is equipped with an ignition device 18 that ignites the fuel-air mixture introduced into the cylinder 11 by spark discharge.

[0011] The hybrid vehicle 1 is provided with an exhaust passage 21 that guides the exhaust gas discharged from the cylinder 11 during operation of the internal combustion engine 10 to the rear of the vehicle. The exhaust passage 21 is equipped with a catalytic converter 22 that oxidizes HC and CO and reduces NOx in the exhaust gas. Downstream of the exhaust from the catalytic converter 22 is a filter 23 that collects particulate matter contained in the exhaust gas. Downstream of the exhaust from the catalytic converter 22 is a differential pressure sensor 83 that detects the differential pressure, which is the difference between the pressure upstream of the filter 23 and the pressure downstream of the filter 23. The differential pressure is a value relating to the exhaust pressure within the exhaust passage 21. The processing circuit 101 acquires the differential pressure detection signal from the differential pressure sensor 83.

[0012] The hybrid vehicle 1 is equipped with a first planetary gear mechanism 40. The first planetary gear mechanism 40 has an external gear sun gear 41 and an internal gear ring gear 42 which is coaxially arranged with the sun gear 41. Between the sun gear 41 and the ring gear 42 are a plurality of pinion gears 43 which mesh with both the sun gear 41 and the ring gear 42. Each pinion gear 43 is supported by a carrier 44 so as to be able to rotate and revolve freely. The carrier 44 of the first planetary gear mechanism 40 is connected to a crankshaft 14, which is the output shaft of the internal combustion engine 10. A first motor generator 71 is connected to the sun gear 41. A ring gear shaft 45 is connected to the ring gear 42. Drive wheels 63 are connected to the ring gear shaft 45 via a reduction mechanism 60, a differential mechanism 61, and a drive shaft 62. The internal combustion engine 10, the first motor generator 71, and the second motor generator 72 are power sources that drive the drive shaft 62. The second motor generator 72 is connected to the ring gear shaft 45 via the second planetary gear mechanism 50.

[0013] The second planetary gear mechanism 50 has an external gear sun gear 51 and an internal gear ring gear 52 which is coaxially arranged with the sun gear 51. Between the sun gear 51 and the ring gear 52 are multiple pinion gears 53 which mesh with both the sun gear 51 and the ring gear 52. Each pinion gear 53 is capable of rotation but is not capable of orbiting. A ring gear shaft 45 is connected to the ring gear 52. A second motor generator 72 is connected to the sun gear 51.

[0014] The processing circuit 101 acquires detection signals from various sensors installed in the internal combustion engine 10. The internal combustion engine 10 is equipped with an air flow meter 82, a crank angle sensor 85, and a water temperature sensor 86 as sensors. The air flow meter 82 is located upstream of the throttle valve 16 in the intake passage 15. The air flow meter 82 detects the intake air volume, which is the flow rate of air flowing through the intake passage 15 that introduces outside air into the internal combustion engine 10. The crank angle sensor 85 is located near the crankshaft 14. The crank angle sensor 85 detects the rotational phase of the crankshaft 14. Based on the detection signal from the crank angle sensor 85, the processing circuit 101 calculates the engine rotational speed NE, which is the rotational speed of the crankshaft 14 of the internal combustion engine 10. The water temperature sensor 86 detects the temperature of the coolant flowing through the cooling water passage of the internal combustion engine 10.

[0015] The processing circuit 101 acquires a detection signal from the accelerator position sensor 80 indicating the amount the driver has pressed the accelerator pedal. The processing circuit 101 acquires a detection signal from the vehicle speed sensor 81 indicating the vehicle speed, which is the driving speed of the hybrid vehicle 1. The processing circuit 101 acquires the State of Charge (SOC), which is the amount of power stored in the battery 77, from the battery 77.

[0016] The processing circuit 101 calculates a required torque, which is a required value of the torque output to the ring gear shaft 45, based on the operation amount of the accelerator pedal and the vehicle speed. The processing circuit 101 determines the torque distribution of the internal combustion engine 10, the first motor generator 71, and the second motor generator 72 according to the required torque and the SOC of the battery 77. The processing circuit 101 controls the internal combustion engine 10, the first motor generator 71, and the second motor generator 72 based on the determined torque distribution. For example, when starting the internal combustion engine 10, the processing circuit 101 causes the first motor generator 71 to function as a starter. Specifically, the control device 100 rotates the sun gear 41 by the first motor generator 71 to rotate the crankshaft 14 and start the internal combustion engine 10. At this time, the reaction force acting on the ring gear shaft 45 from the internal combustion engine 10 is canceled by the torque of the second motor generator 72.

[0017] When a predetermined stop condition is satisfied, the processing circuit 101 automatically stops the operation of the internal combustion engine 10, and when a predetermined start condition is satisfied, the processing circuit 101 executes intermittent operation control to automatically start the internal combustion engine 10. That is, the processing circuit 101 executes intermittent operation control to repeatedly perform the operation and the operation stop of the internal combustion engine 10 according to the driving situation of the hybrid vehicle 1. The processing circuit 101 can prohibit the execution of the intermittent operation control. When the intermittent operation control is prohibited, the processing circuit 101 does not automatically stop the internal combustion engine 10 even if the condition for automatically stopping the internal combustion engine 10 is satisfied. When the intermittent operation control is prohibited during the intermittent stop of the internal combustion engine 10, the intermittent stop is interrupted and the internal combustion engine 10 is restarted.

[0018] <Regarding differential pressure detection control> The processing circuit 101 executes differential pressure detection control for repeatedly detecting the front-rear differential pressure on the condition that the intake air amount, which is a value correlated with the exhaust pressure, is not less than a first predetermined value. The processing circuit 101 repeatedly executes a series of processes shown in FIG. 2 during a trip.

[0019] As shown in FIG. 2, when starting this series of processes, in the process of step S10, the processing circuit 101 determines whether the filter defect determination flag is "OFF". The filter defect determination flag is a flag indicating whether the presence or absence of a defect in the filter 23 has been determined. That the filter defect determination flag is "ON" indicates that the processing circuit 101 has determined the presence or absence of a defect in the filter 23. That the filter defect determination flag is "OFF" indicates that the processing circuit 101 has not determined the presence or absence of a defect in the filter 23. The filter defect determination flag is set to "OFF" at the start of a trip. The filter defect determination flag may be set to "OFF" at the end of a trip.

[0020] When the filter defect determination flag is "OFF" (step S10: YES), the processing circuit 101 advances the process to step S11. When the filter defect determination flag is not "OFF", that is, when the filter defect determination flag is "ON" (step S10: NO), the processing circuit 101 ends the series of processes shown in FIG. 2 without performing the subsequent processes.

[0021] In the process of step S11, the processing circuit 101 determines whether the engine rotational speed NE of the internal combustion engine 10 is equal to or greater than a predetermined value. When the engine rotational speed NE is equal to or greater than the predetermined value (step S11: YES), the processing circuit 101 advances the process to step S12. When the engine rotational speed NE is less than the predetermined value (step S11: NO), the processing circuit 101 ends the series of processes shown in FIG. 2 without performing the subsequent processes.

[0022] In the process of step S12, the processing circuit 101 determines whether the intake air amount, which is a value correlated with the exhaust pressure, is equal to or greater than a first predetermined value, which is an appropriate value in the detection of the differential pressure between the front and rear. When the intake air amount is equal to or greater than the first predetermined value (step S12: YES), the processing circuit 101 advances the process to step S13. When the intake air amount is less than the first predetermined value (step S12: NO), the processing circuit 101 ends the series of processes shown in FIG. 2 without performing the subsequent processes.

[0023] In step S13, the processing circuit 101 starts differential pressure detection control to acquire the differential pressure across the front and rear. Specifically, the processing circuit 101 controls the differential pressure sensor 83 to start detecting the differential pressure across the front and rear. The processing circuit 101 acquires a differential pressure detection signal from the differential pressure sensor 83. Based on the acquired differential pressure detection signal, the processing circuit 101 calculates the differential pressure across the front and rear. The processing circuit 101 stores the calculated differential pressure across the front and rear in the storage device 102. The storage device 102 can store multiple differential pressure data sets. The processing circuit 101 stores the acquired differential pressure data in the storage device 102. After that, the processing circuit 101 proceeds to step S14.

[0024] In step S14, the processing circuit 101 determines whether the intake air volume is less than a first default value. If the intake air volume is less than the first default value (step S14: YES), the processing circuit 101 proceeds to step S15. In step S15, the processing circuit 101 terminates the differential pressure detection control. That is, the processing circuit 101 controls the differential pressure sensor 83 to terminate the detection of the differential pressure across the front and rear. After that, the processing circuit 101 terminates the series of processes shown in Figure 2.

[0025] The processing circuit 101 continues differential pressure detection control if the intake air volume is not less than the first default value, i.e., if the intake air volume is greater than or equal to the first default value (step S14: NO). The processing circuit 101 continues to acquire the front-to-rear differential pressure detection signal from the differential pressure sensor 83 and calculates the front-to-rear differential pressure data until the intake air volume falls below the first default value. The processing circuit 101 stores the acquired front-to-rear differential pressure data in the storage device 102.

[0026] <Regarding output boost control> During differential pressure detection control, if the differential pressure across the system falls below a second default value which is greater than a first default value, the processing circuit 101 starts output boosting control to increase the requested output Pe to the internal combustion engine 10. Output boosting control is a control that increases the output of the internal combustion engine 10 and also increases the amount of electricity generated by the motor generator.

[0027] The processing circuit 101 repeatedly executes the series of processes shown in Figure 3 while differential pressure detection control is being performed. As shown in Figure 3, when this series of processes is started, the processing circuit 101 determines in step S20 whether the intake air volume is less than the second default value. If the intake air volume is less than the second default value (step S20: YES), the processing circuit 101 proceeds to step S21. If the intake air volume is not less than the second default value, that is, if the intake air volume is greater than or equal to the second default value (step S20: NO), the processing circuit 101 terminates the series of processes shown in Figure 3.

[0028] In step S21, the processing circuit 101 starts output boosting control. After that, the processing circuit 101 proceeds to step S22. Output boost control is a control that increases the requested output Pe, which corresponds to the target value in the output control of the internal combustion engine 10 performed by the processing circuit 101, compared to when output boost control is not performed. When output boost control is started, the output of the internal combustion engine 10 increases, so the processing circuit 101 increases the amount of power generated by the first motor generator 71. The processing circuit 101 suppresses fluctuations in power at the ring gear shaft 45 by using the increased output resulting from the increased correction of the requested output Pe for power generation. The power generated by the first motor generator 71 is charged to the battery 77. At this time, the internal combustion engine 10 is generating an output greater than the output required to drive the drive shaft 62. Due to the increase in the requested output Pe by output boost control, the intake air amount is maintained at or above the second default value. Output boost control is not limited to control that maintains the intake air amount at or above the second default value. For example, output boost control may be a control that maintains the requested output Pe at a constant amount. For example, output boost control may be a control that maintains the requested output Pe at the time the output boost control was initiated. For example, output boost control may be a control that increases the requested output Pe by a certain amount.

[0029] In step S22, the processing circuit 101 determines whether the termination condition for output boost control is met. The termination condition for output boost control will be described later. If the termination condition for output boost control is met (step S22: YES), the processing circuit 101 proceeds to step S23. In step S23, the processing circuit 101 terminates the output boost control. After that, the processing circuit 101 temporarily terminates the series of processes shown in Figure 3. If the termination condition for output boost control is not met (step S22: NO), the processing circuit 101 continues the output boost control.

[0030] <Conditions for terminating output boost control> The processing circuit 101 performs a series of processes to determine whether the termination condition for output boost control is met while output boost control is being executed. The processing circuit 101 repeatedly performs this series of processes while output boost control is being executed.

[0031] As shown in Figure 4, when this series of processes is executed, in the process of step S30, the processing circuit 101 determines whether the state of the battery 77 has met the predetermined conditions, by determining whether the state of charge (SOC), which is information about the state of the battery 77, is equal to or greater than a predetermined value. If the SOC of the battery 77 is equal to or greater than a predetermined value (step S30: YES), the processing circuit 101 proceeds to step S31.

[0032] In step S31, the processing circuit 101 limits the charging of power to the battery 77. Then, the processing circuit 101 proceeds to step S32. In step S32, the processing circuit 101 terminates the output boosting control. After that, the processing circuit 101 temporarily terminates the series of processes shown in Figure 4.

[0033] If the State of Charge (SOC) of the battery 77 is less than a predetermined value (step S30: NO), the processing circuit 101 proceeds to step S33. In step S33, the processing circuit 101 determines whether the output boost control has continued for a predetermined time. If the output boost control has continued for a predetermined time (step S33: YES), the processing circuit 101 proceeds to step S32. In step S32, the processing circuit 101 terminates the output boost control. After that, the processing circuit 101 temporarily terminates the series of processes shown in Figure 4. If the output boost control has not continued for a predetermined time (step S33: NO), the processing circuit 101 temporarily terminates the series of processes shown in Figure 4 while continuing the output boost control.

[0034] <Regarding Missing Data Detection Control> The processing circuit 101 performs defect detection control to determine whether or not there is a defect in the filter 23 using multiple differential pressure data collected by differential pressure detection control. The processing circuit 101 repeatedly performs defect detection control during the trip until the filter defect detection flag is "ON". If the filter defect detection flag is "ON", the processing circuit 101 does not perform defect detection control. Note that the processing circuit 101 may be configured to perform defect detection control even if the filter defect detection flag is "ON".

[0035] As shown in Figure 5, when this series of processes is started, the processing circuit 101 determines in step S40 whether the filter defect detection flag is "OFF" or not. If the filter defect detection flag is "OFF" (step S40: YES), the processing circuit 101 proceeds to step S41. If the filter defect detection flag is not "OFF", that is, if the filter defect detection flag is "ON" (step S40: NO), the processing circuit 101 terminates the series of processes shown in Figure 5 without performing the subsequent processes.

[0036] In step S41, the processing circuit 101 determines whether or not it has acquired a predetermined number of front-to-rear differential pressure data points. The processing circuit 101 determines that it has acquired a predetermined number of front-to-rear differential pressure data points if the number of front-to-rear differential pressure data points stored in the storage device 102 is greater than or equal to the predetermined number. If the processing circuit 101 has acquired a predetermined number of front-to-rear differential pressure data points (step S41: YES), it proceeds to step S42. If the processing circuit 101 has not acquired a predetermined number of front-to-rear differential pressure data points (step S41: NO), it terminates the series of processes shown in Figure 5 without performing the subsequent processes.

[0037] In step S42, the processing circuit 101 calculates the average value of the acquired differential pressure data by averaging it. After that, the processing circuit 101 proceeds to step S43.

[0038] In step S43, the processing circuit 101 determines whether the average value of the differential pressure data across the front and rear is greater than or equal to a predetermined value. If the average value of the differential pressure across the front and rear is greater than or equal to a predetermined value (step S43: YES), the processing circuit 101 proceeds to step S44. In step S44, the processing circuit 101 makes a normal determination, which means that there are no defects in the filter 23. After that, the processing circuit 101 proceeds to step S46. In step S46, the processing circuit 101 sets the filter defect determination flag to ON. After that, the processing circuit 101 completes the series of processes shown in Figure 5. If the average value of the differential pressure across the front and rear is less than a predetermined value (step S43: NO), the processing circuit 101 proceeds to step S45. In step S45, the processing circuit 101 makes an abnormal determination, which means that there are defects in the filter 23. After that, the processing circuit 101 proceeds to step S46. In step S46, the processing circuit 101 sets the filter defect detection flag to ON. After that, the processing circuit 101 completes the series of processes shown in Figure 5.

[0039] The processing circuit 101 may use a value other than the average value of the differential pressure data in step S43. For example, in step S43, the processing circuit 101 may determine whether the mode of the differential pressure data stored in the storage device 102 is greater than or equal to a predetermined value.

[0040] <Operation of this embodiment> The processing circuit 101 of the control device 100 performs differential pressure detection control, which repeatedly detects the differential pressure between the front and rear sections, provided that the intake air volume, a value correlated with the exhaust pressure, is greater than or equal to a first default value. When the intake air volume falls below a second default value, which is greater than the first default value, the processing circuit 101 starts output boosting control. This makes it easier to maintain the differential pressure between the front and rear sections at a value greater than the first default value, and thus makes it easier to continue the differential pressure detection control.

[0041] <Effects of this embodiment> (1) The control device 100 described above can ensure an opportunity to detect the differential pressure before and after the filter 23, which is necessary to determine whether or not the filter 23 is defective.

[0042] (2) The processing circuit 101 terminates the output boost control when it has been performed for a predetermined time. During the period when the processing circuit 101 is performing the output boost control, the internal combustion engine 10 generates an output greater than the output required to drive the drive shaft 62. Therefore, when the processing circuit 101 is performing the output boost control, the amount of fuel injected by the internal combustion engine 10 increases. As a result, while the processing circuit 101 is performing the output boost control, the fuel consumption of the hybrid vehicle 1 increases compared to when the output boost control is not being performed. Therefore, the processing circuit 101 terminates the output boost control when it has been performed for a predetermined time. This allows the control device 100 to ensure an opportunity to detect the differential pressure between the front and rear while suppressing an increase in the fuel consumption of the hybrid vehicle 1.

[0043] (3) While the processing circuit 101 is performing output boost control, the output of the internal combustion engine 10 does not decrease easily even if the hybrid vehicle 1 is decelerated by the driver's braking operation. In other words, even if the speed of the hybrid vehicle 1 decreases, the driving sound of the internal combustion engine 10 does not change easily. In particular, if the output boost control is continued until the State of Charge (SOC) of the battery 77 is above a predetermined value, depending on the state of the battery 77, the period during which the driving sound of the internal combustion engine 10 does not change even if the speed of the hybrid vehicle 1 decreases may be extended. If the driving sound of the internal combustion engine 10 does not change even if the speed of the hybrid vehicle 1 decreases, it may cause discomfort to the driver of the hybrid vehicle 1. The processing circuit 101 terminates the output boost control if the output boost control has continued for a predetermined time, even if the SOC of the battery 77 is below a predetermined value. Therefore, the control device 100 can shorten the period during which the driving sound of the internal combustion engine 10 does not change even if the speed of the hybrid vehicle 1 decreases. This allows the control device 100 to shorten the period during which the driving noise of the internal combustion engine 10 causes discomfort to the driver, provided that it has an opportunity to detect the differential pressure between the front and rear axles.

[0044] (4) In order for the processing circuit 101 to continue output boosting control, it is necessary to charge the battery 77 by converting the surplus output generated by the internal combustion engine 10 into electricity. If the battery 77 is overcharged, the performance of the battery 77 may deteriorate. The processing circuit 101 acquires the state of charge (SOC) of the battery 77 as information regarding the state of the battery 77. If the SOC of the battery 77 is above a predetermined value, the processing circuit 101 limits the charging of electricity to the battery 77 and terminates the output boosting control. In this way, the processing circuit 101 prevents the battery 77 from being overcharged. Therefore, the control device 100 can ensure an opportunity to detect the differential pressure between the front and rear while protecting the battery 77.

[0045] (5) When the defect detection control is completed, the processing circuit 101 turns on the filter defect detection flag. When the filter defect detection flag is ON, the processing circuit 101 does not execute differential pressure detection control. While the processing circuit 101 is executing differential pressure detection control, the processing circuit 101 may execute output boost control. When the processing circuit 101 is executing output boost control, the amount of fuel injected by the internal combustion engine 10 increases. Therefore, while the processing circuit 101 is executing differential pressure detection control, the fuel consumption of the hybrid vehicle 1 may increase compared to when differential pressure detection control is not being executed. Therefore, when the filter defect detection flag, which indicates that the defect detection control is completed, is ON, the processing circuit 101 does not execute differential pressure detection control. In this way, the control device 100 can suppress the increase in fuel consumption by not executing differential pressure detection control after determining whether or not there is a defect in the filter 23.

[0046] <Example of changes> This embodiment can be implemented with the following modifications. This embodiment and the following modifications to this embodiment can be combined with each other to the extent that they do not contradict each other technically.

[0047] The processing circuit 101 may determine whether or not to terminate the output boost control based solely on whether or not the State of Charge (SOC) of the battery 77 is equal to or greater than a predetermined value. The processing circuit 101 may determine whether or not to terminate the output boost control based solely on whether or not the output boost control has continued for a predetermined time.

[0048] The processing circuit 101 may use information other than the State of Charge (SOC) of the battery 77 as information regarding the state of the battery 77 as a condition for terminating the output boost control. For example, the processing circuit 101 may use the temperature of the battery 77 as information regarding the state of the battery 77 as a default condition. In this case, the processing circuit 101 will limit the charging of power to the battery 77 and terminate the output boost control when the temperature of the battery 77 exceeds a default temperature.

[0049] The processing circuit 101 may perform differential pressure detection control even if the filter defect detection flag is ON. The processing circuit 101 may use a value other than the intake air volume as a value correlated with the exhaust pressure. For example, the processing circuit 101 may use the engine load ratio KL as a value correlated with the exhaust pressure. The engine load ratio KL represents the ratio of the current cylinder inflow air volume to the cylinder inflow air volume when the internal combustion engine 10 is operated steadily at full load at the current engine speed NE. The cylinder inflow air volume is the amount of air that flows into each of the multiple cylinders 11 during the intake stroke. When the engine speed NE is the same, the higher the engine load ratio KL, the greater the exhaust pressure. The processing circuit 101 may be set to start detecting the differential pressure between the front and rear cylinders when the engine speed NE is above a predetermined value and the engine load ratio KL is above a predetermined value.

[0050] The processing circuit 101 may use the exhaust flow rate, which is the sum of the intake air volume and the mass flow rate of the fuel injected from the fuel injection valve 17, as a value that correlates with the exhaust pressure. If the hybrid vehicle 1 is equipped with a sensor that directly measures exhaust pressure, the processing circuit 101 may use the pressure measured by the sensor as a value correlated with the exhaust pressure.

[0051] The control device 100 may be configured as a circuit including one or more processors that execute various processes according to a computer program (software). Alternatively, the control device 100 may be configured as a circuit including one or more dedicated hardware circuits, such as application-specific integrated circuits (ASICs), or a combination thereof, that execute at least some of the various processes. The processor includes a CPU and memory such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to execute processes. Memory, or computer-readable media, includes any available media that can be accessed by a general-purpose or dedicated computer. [Explanation of symbols]

[0052] 1…Hybrid vehicle, 10…Internal combustion engine, 15…Intake passage, 21…Exhaust passage, 23…Filter, 62…Drive shaft, 77…Battery, 82…Airflow meter, 83…Differential pressure sensor, 100…Control device, 101…Processing circuit, Pe…Requested output

Claims

1. A control device applicable to a hybrid vehicle, comprising: an internal combustion engine and a motor generator as power sources for driving the drive shaft; a battery for charging the power generated by the motor generator using the output of the internal combustion engine; an exhaust passage for guiding exhaust from the internal combustion engine to the rear of the vehicle; a filter for collecting particulate matter contained in the exhaust; and a differential pressure sensor for detecting the front-to-rear differential pressure, which is the difference between the pressure upstream of the filter and the pressure downstream of the filter; Equipped with a processing circuit, The processing circuit described above Condition that the value correlated with the exhaust pressure is greater than or equal to a first predetermined value, a differential pressure detection control is performed to repeatedly detect the differential pressure across the front and rear. During the execution of the differential pressure detection control, if the value correlated with the exhaust pressure falls below a second default value which is greater than the first default value, an output boost control is initiated to increase the output required by the internal combustion engine and increase the amount of power generated by the motor generator, thereby increasing the output required by the internal combustion engine. Using the multiple data of the differential pressures before and after the differential pressure collected by the differential pressure detection control, a defect determination control is executed to determine whether or not there is a defect in the filter. Control system for hybrid vehicles.

2. If the output boost control continues for a predetermined time, the output boost control will be terminated. A control device for a hybrid vehicle according to claim 1.

3. The processing circuit acquires information regarding the state of the battery, When the battery state meets the predetermined conditions, the charging of power to the battery is restricted and the output boost control is terminated. A control device for a hybrid vehicle according to claim 1.

4. When the aforementioned missing data detection control is completed, control is performed to turn on the filter missing data detection flag. If the filter defect detection flag is ON, the differential pressure detection control will not be performed. A control device for a hybrid vehicle according to claim 1.

5. As a value correlated with the exhaust pressure, the intake air volume detected by an airflow meter, which detects the flow rate of air flowing through the intake passage that introduces outside air into the internal combustion engine, is used. A control device for a hybrid vehicle according to any one of claims 1 to 4.

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