JP2021110275A - Control device for fuel supply system - Google Patents

Abstract

To provide a control device for a fuel supply system, capable of specifying a site where abnormality occurs.SOLUTION: The control device includes an execution device and a storage device. The execution deice executes information acquisition processing (S200-S260), and determination processing (S300). In the information acquisition processing, information of a magnitude relation with a normal range about each of five values for a fuel pressure, an integration term in fuel pressure feedback processing, a voltage value, a current value, and a revolving speed is stored as primary information (S230) when the value different from the value deviating from the normal range at the time of starting the information acquisition processing, out of the five values, deviates from the normal range (S210: YES), and stored as secondary information (S260) when finishing the information acquisition processing after a given time passes (S200: NO). In the determination processing, the presence or absence of abnormality in the fuel supply system and a site where the abnormality occurs are specified on the basis of the primary information and the secondary information that the storage device stores in the information acquisition processing.SELECTED DRAWING: Figure 18

Description

The present invention relates to a control device for a fuel supply system of an internal combustion engine.

Patent Document 1 includes, as a means for determining an abnormality in the fuel supply system of an internal combustion engine, a fuel leak determining means having a function of determining the presence or absence of a fuel leak from the balance between the fuel discharge amount and the fuel consumption of the fuel pump. The control device is disclosed.

Japanese Unexamined Patent Publication No. 2005-146888

By the way, as an abnormality of the fuel supply system, there may be an abnormality of various parts. For example, the impeller of the fuel pump may malfunction or the fuel filter may be clogged.
Since all of them affect the fuel supply, it is not possible to identify which part has an abnormality only by detecting that the fuel supply is excessive or deficient. If the part where the abnormality occurs can be identified, the part causing the abnormality can be efficiently repaired.

Hereinafter, means for solving the above problems and their actions and effects will be described.
In order to solve the above problems, the control device of the fuel supply system detects the electric fuel pump, the fuel injection valve for injecting fuel, and the fuel pressure in the fuel pipe from the fuel pump to the fuel injection valve. The pressure sensor, the voltage value and the current value in the fuel pump, and the rotation speed of the impeller per unit time are detected, and the power supply to the fuel pump is feedback-controlled by pulse width modulation so as to realize the required rotation speed. Applies to fuel supply systems with a pump controller. This control device determines the difference between the required rotation speed calculation process that calculates the required rotation speed based on the required fuel supply amount and the required fuel pressure, and the detection value of the fuel pressure detected by the pressure sensor and the required fuel pressure. It is provided with an execution device and a storage device that execute the fuel pressure feedback process for correcting the required fuel supply amount so as to be small and output the required rotation speed to the pump control device. Then, in this control device, the executing device has any of the five values of the fuel pressure detected by the pressure sensor, the integration term in the fuel pressure feedback process, the voltage value, the current value, and the rotation speed. This is a process that is executed for a certain period of time from the time when the value deviates from the normal range, and among the above five values, a value different from the value that deviates from the normal range when the process is started deviates from the normal range. At that time, the information on the magnitude relationship between the five values at that time and the normal range is stored in the storage device as primary information, and when the processing is completed after the certain period has elapsed, the above 5 at that time. Based on the information acquisition process that stores information on the magnitude relationship between the two values with the normal range as secondary information in the storage device, and the primary information and the secondary information stored in the storage device in the information acquisition process. The determination process for identifying the presence / absence of an abnormality and the part where the abnormality has occurred in the fuel supply system is executed.

In the above fuel supply system, feedback control regarding the number of revolutions by the pump control device and feedback control based on the fuel pressure by the fuel pressure feedback process executed by the control device are executed. In such a fuel supply system, the fuel pump is controlled through these two feedback controls so that the fuel pressure does not deviate from the required fuel pressure.

While an abnormality occurs in the fuel supply system and the control for absorbing the fluctuation of the fuel pressure due to the abnormality is performed through these two feedback controls, the above five values fluctuate. The mode of time-series change of the above five values differs depending on the location where the abnormality occurs.

On the other hand, in the above control device, the execution device changes the fuel pressure due to an abnormality for a certain period of time after one of the above five values deviates from the normal range, that is, through feedback control. The information acquisition process is executed when the control for absorption is performed. Then, in the information acquisition process, the primary information and the secondary information, which are information about the above five values at the time points separated in time series, are stored in the storage device. Then, the executing device performs the determination process based on the primary information and the secondary information stored in the storage device. Therefore, in the determination process, it is possible to reflect the mode of time-series change of the above five values. Therefore, according to the above control device, it is possible to identify the site where the abnormality is occurring.

Since the normal range is set based on the fuel injection amount, it does not change unless the fuel injection amount changes.
In one aspect of the control device of the fuel supply system, the storage device stores determination data in which the combination of the primary information and the secondary information and the relationship between the occurrence site of the abnormality are stored, and the execution device. In the determination process, the primary information and the secondary information stored in the information acquisition process are collated with the determination data to identify the presence or absence of an abnormality in the fuel supply system and the part where the abnormality occurs. do.

According to the above configuration, the primary information and the secondary information can be collated with the determination data to identify the part where the abnormality has occurred.
When the impeller malfunctions, the rotation speed of the impeller decreases and the fuel supply amount becomes insufficient, so that the fuel pressure decreases. As a result, the number of revolutions or the fuel pressure first deviates from the normal range. Then, the information acquisition process is started from this point.

After that, the power supply to the fuel pump is increased by the feedback control of the rotation speed by the pump control device, and the voltage value and the current value are increased. As a result, the voltage value or the current value deviates from the normal range, and the information on the magnitude relationship between the above five values and the normal range at this time is stored as the primary information.

In the case of impeller malfunction, which makes it difficult for the impeller to rotate, the impeller's rotation speed recovers and the fuel pressure recovers quickly when the force that drives the impeller increases due to the increase in voltage and current values. The integration term in pressure feedback control hardly changes and does not deviate from the normal range. Therefore, in this case, the primary information is information indicating that the integral term is within the normal range and the voltage value or current value is higher than the normal range.

When the rotation speed of the impeller is restored and the fuel pressure is restored in this way, the increase in the voltage value and the current value due to the feedback control of the rotation speed is stopped. Therefore, the secondary information stored when the information acquisition process is completed after a certain period of time is that the fuel pressure, integral term, and rotation speed are within the normal range, and the voltage value and current value are higher than the normal range. It becomes the information to show.

Therefore, in one aspect of the control device of the fuel supply system, the execution device is information that the primary information indicates that the integration term is within the normal range and the voltage value or the current value is higher than the normal range. When the secondary information is information indicating that the fuel pressure, the integral term, and the rotation speed are within the normal range, and the voltage value and the current value are higher than the normal range, the determination process is performed. It is determined that the impeller is malfunctioning.

According to such a configuration, it is possible to determine that the impeller malfunction has occurred based on the primary information and the secondary information.
If the suction filter provided at the suction port of the fuel pump is clogged, it will be difficult to pump the fuel. Therefore, even if the impeller is rotating at a rotation speed that matches the required rotation speed, the amount of fuel supplied. Is insufficient and the fuel pressure drops. As a result, the fuel pressure first deviates from the normal range. Then, the information acquisition process is started from this point.

Since the impeller rotates at a rotation speed that matches the required rotation speed, the voltage value, current value, and rotation speed change within the normal range, but the fuel pressure continues to be below the required fuel pressure. The integration term in fuel pressure feedback control gradually increases. As a result, the integral term first deviates from the normal range, and information on the magnitude relationship between the above five values and the normal range at this time is stored as primary information. In this case, the primary information is information indicating that the fuel pressure is lower than the normal range, the voltage value, the current value, and the rotation speed are within the normal range, and the integral term is higher than the normal range.

If the required fuel supply amount is increased through the feedback control of the fuel pressure as the fuel pressure continues to be lower than the required fuel pressure, the required rotation speed increases, and the voltage value, the current value, and the rotation speed increase. It will increase. As a result, the amount of fuel supplied increases even when clogging occurs, and the fuel pressure gradually recovers.

When the fuel pressure is recovered in this way, the increase in the integral term due to the feedback control of the fuel pressure and the increase in the voltage value, the current value, and the rotation speed are stopped. Therefore, the secondary information stored when the information acquisition process is completed after a certain period of time is that the fuel pressure is within the normal range and the integral term, voltage value, current value, and rotation speed are higher than the normal range. It becomes the information to show.

Therefore, in one aspect of the control device of the fuel supply system, the execution device has the primary information that the fuel pressure is lower than the normal range and the voltage value, the current value, and the rotation speed are within the normal range. Information indicating that the integration term is higher than the normal range, and the secondary information is that the fuel pressure is within the normal range and the integration term, the voltage value, the current value, and the rotation speed are higher than the normal range. When the information indicates that, in the determination process, it is determined that the suction filter in the fuel pump is clogged.

According to such a configuration, it is possible to determine that the suction filter is clogged based on the primary information and the secondary information.
If an abnormality occurs in the pump control device, the fuel pump cannot be driven properly, and the voltage value, the current value, and the rotation speed of the impeller may decrease significantly. Therefore, when such an abnormality occurs, any one of the voltage value, the current value, and the rotation speed first deviates from the normal range. Then, the information acquisition process is started from this point.

If an abnormality occurs in the pump control device and this happens, the pump control device cannot control the rotation speed feedback, so the voltage and current values and the impeller rotation speed continue to remain at extremely low levels. It will be. As a result, the fuel pressure gradually decreases. When the fuel pressure drops and deviates from the normal range, information on the magnitude relationship between the above five values and the normal range at that time is stored as primary information. At this point, the integral term has not increased much yet. Therefore, the primary information is information indicating that the fuel pressure, voltage value, current value, and rotation speed are lower than the normal range and the integral term is within the normal range.

After that, the fuel pressure continues to be below the required fuel pressure, so the integral term becomes large. Due to the feedback control of the fuel pressure, the required fuel supply amount is increased and the required rotation speed is also increased. However, when an abnormality occurs in the pump control device, the voltage value, the current value, and the impeller rotation speed continue to remain at extremely low levels, and the fuel pressure does not recover. Therefore, the secondary information stored when the information acquisition process is completed after a certain period of time has a fuel pressure, a voltage value, a current value, and a rotation speed lower than the normal range and an integral term higher than the normal range. It becomes information indicating that.

Therefore, in one aspect of the control device of the fuel supply system, the execution device has the primary information that the fuel pressure, the voltage value, the current value, and the rotation speed are lower than the normal range, and the integration term is normal. It is information indicating that it is within the range, and the secondary information indicates that the fuel pressure, the voltage value, the current value, and the rotation speed are lower than the normal range and the integration term is higher than the normal range. When the information is shown, it is determined in the determination process that an abnormality has occurred in the pump control device.

According to such a configuration, it is possible to determine that an abnormality has occurred in the pump control device based on the primary information and the secondary information.
If the pressure sensor has an abnormality, it may not be possible to detect the actual fuel pressure, and it may continue to output a signal indicating a value far from the actual pressure. Therefore, when such an abnormality occurs, the fuel pressure first deviates from the normal range. Then, the information acquisition process is started from this point. For example, if the pressure sensor continues to output a signal indicating a pressure lower than the actual fuel pressure, the information acquisition process starts when the fuel pressure value first drops and deviates from the normal range. Will be done.

In this case, since the fuel pressure continues to be below the required fuel pressure, the integration term in the fuel pressure feedback control gradually increases. As a result, the integration term deviates from the normal range, and information on the magnitude relationship between the above five values and the normal range at this time is stored as primary information. In this case, the primary information is information indicating that the fuel pressure is lower than the normal range, the voltage value, the current value, and the rotation speed are within the normal range, and the integral term is higher than the normal range.

If the required fuel supply amount is increased through the feedback control of the fuel pressure as the fuel pressure continues to be lower than the required fuel pressure, the required rotation speed increases, and the voltage value, the current value, and the rotation speed increase. It will increase. However, if an abnormality occurs in the pressure sensor, the voltage value, current value, and impeller rotation speed will increase, and the pressure sensor will operate even if the actual fuel pressure increases due to the increase in fuel supply. Since the output signal does not change, the fuel pressure value does not recover. Therefore, the secondary information stored when the information acquisition process is terminated after a certain period of time is such that the fuel pressure is lower than the normal range and the integral term, voltage value, current value, and rotation speed are higher than the normal range. It becomes information indicating that.

Therefore, in one aspect of the control device of the fuel supply system, the execution device has the primary information that the fuel pressure is lower than the normal range and the voltage value, the current value, and the rotation speed are within the normal range. Information indicating that the integration term is higher than the normal range, and the secondary information is that the fuel pressure is lower than the normal range and the integration term, the voltage value, the current value, and the rotation speed are higher than the normal range. When the information indicates that the voltage is high, it is determined in the determination process that an abnormality has occurred in the pressure sensor.

According to such a configuration, it is possible to determine that an abnormality has occurred in the pressure sensor based on the primary information and the secondary information.
It is possible that the pressure sensor will continue to output a signal indicating a pressure higher than the normal range. In this case, the information acquisition process is started by first increasing the fuel pressure value and deviating from the normal range.

In this case, since the state in which the fuel pressure exceeds the required fuel pressure continues, the integral term in the feedback control of the fuel pressure gradually becomes smaller and becomes a negative value. As a result, the integration term deviates from the normal range, and information on the magnitude relationship between the above five values and the normal range at this time is stored as primary information. In this case, the primary information is information indicating that the fuel pressure is higher than the normal range, the integral term is lower than the normal range, and the voltage value, the current value, and the rotation speed are within the normal range.

If the required fuel supply amount decreases through the feedback control of the fuel pressure as the fuel pressure continues to exceed the required fuel pressure, the required rotation speed decreases, and the voltage value, current value, and rotation speed decrease. It will decrease. However, if an abnormality occurs in the pressure sensor, the voltage value, current value, and impeller rotation speed will decrease, and the pressure sensor will operate even if the actual fuel pressure decreases due to the decrease in fuel supply. Since the output signal does not change, the fuel pressure value does not decrease. Therefore, the secondary information stored when the information acquisition process is completed after a certain period of time has an integral term, a voltage value, a current value, and a rotation speed lower than the normal range and a fuel pressure higher than the normal range. It becomes information indicating that.

Therefore, in one aspect of the control device of the fuel supply system, the execution device has the primary information that the integration term is lower than the normal range, the voltage value, the current value, and the rotation speed are within the normal range, and the rotation speed is within the normal range. Information indicating that the fuel pressure is higher than the normal range, and the secondary information is that the integration term, the voltage value, the current value, and the rotation speed are lower than the normal range, and the fuel pressure is lower than the normal range. When the information indicates that the voltage is high, it is determined in the determination process that an abnormality has occurred in the pressure sensor.

According to such a configuration, it is possible to determine that an abnormality has occurred in the pressure sensor based on the primary information and the secondary information.
When the input of the required rotation speed to the pump control device is interrupted, the pump control device does not drive the fuel pump, so that the voltage value, the current value, and the rotation speed of the impeller become "0". Therefore, when such an abnormality occurs, the voltage value, the current value, and the rotation speed deviate from the normal range. Then, the information acquisition process is started from this point.

In such a state, the fuel pump stops, so that the fuel pressure gradually decreases. When the fuel pressure drops and deviates from the normal range, information on the magnitude relationship between the above five values and the normal range at that time is stored as primary information. At this point, the integral term has not increased much yet. Therefore, the primary information is information indicating that the fuel pressure is lower than the normal range, the integral term is within the normal range, and the voltage value, the current value, and the rotation speed are "0".

After that, the fuel pressure continues to be below the required fuel pressure, so the integral term becomes large. Due to the feedback control of the fuel pressure, the required fuel supply amount is increased and the required rotation speed is also increased. However, when the input of the required rotation speed to the pump control device is interrupted, the pump control device does not drive the fuel pump, so that the voltage value, the current value, and the rotation speed of the impeller remain "0" and do not change. Therefore, the fuel pressure does not recover. Therefore, the secondary information stored when the information acquisition process is terminated after a certain period of time is such that the fuel pressure is lower than the normal range, the integral term is higher than the normal range, and the voltage value, current value, and rotation speed are stored. Is information indicating that is "0".

Therefore, in one aspect of the control device of the fuel supply system, the execution device has the primary information that the fuel pressure is lower than the normal range and the integration term is within the normal range, and the voltage value, the current value, and the current value are described. Information indicating that the number of revolutions is "0", and the secondary information is that the fuel pressure is lower than the normal range and the integration term is higher than the normal range, and the voltage value, the current value, and the above. When the information indicates that the number of revolutions is "0", it is determined in the determination process that the input of the required number of revolutions to the pump control device is interrupted.

According to such a configuration, it can be determined that the input of the required rotation speed to the pump control device is interrupted based on the primary information and the secondary information.
When the fuel runs out, the fuel pump sucks in air and spins, which reduces the load on the fuel pump motor. Then, the voltage value and the current value decrease through the feedback of the rotation speed by the pump control device. As a result, the voltage value or the current value deviates from the normal range. Then, the information acquisition process is started from this point.

Due to the lack of fuel, the supply of fuel by the fuel pump is delayed, and the fuel pressure gradually decreases. When the fuel pressure drops and deviates from the normal range, information on the magnitude relationship between the above five values and the normal range at that time is stored as primary information. At this point, the integral term has not increased much yet. Therefore, the primary information is information indicating that the fuel pressure, voltage value, and current value are lower than the normal range, and the integral term and the rotation speed are within the normal range.

After that, the fuel pressure continues to be below the required fuel pressure, so the integral term becomes large. Due to the feedback control of the fuel pressure, the required fuel supply amount is increased and the required rotation speed is also increased. As a result, the voltage value, the current value, and the rotation speed are increased through the feedback control of the rotation speed by the pump control device. However, when the fuel runs out, the fuel pressure does not recover because the fuel supply amount does not increase even if the rotation speed is increased. Therefore, the secondary information stored when the information acquisition process is terminated after a certain period of time is information indicating that the fuel pressure is lower than the normal range and the integral term and the rotation speed are higher than the normal range. ..

Therefore, in one aspect of the control device of the fuel supply system, the execution device has the primary information that the fuel pressure, the voltage value, and the current value are lower than the normal range, and the integral term and the rotation speed are normal. When the information indicates that the fuel pressure is within the range and the secondary information is information indicating that the fuel pressure is lower than the normal range and the integral term and the rotation speed are higher than the normal range, the determination is made. In the process, it is determined that the fuel has run out.

According to such a configuration, it can be determined that the fuel has run out based on the primary information and the secondary information.

The schematic diagram which shows the structure of the control device which is one Embodiment of the control device of a fuel supply system, and the fuel supply system which is the control target of the control device. The block diagram which shows the flow of the process about the fuel pressure control executed by the control device of the same embodiment. A graph showing the relationship between fuel temperature and required fuel pressure. A timing chart showing changes in (a) fuel pressure, (b) integration term, (c) voltage value, (d) current value, (e) rotation speed, and (f) fuel injection amount in a normal state. The transition of (a) fuel pressure, (b) integration term, (c) voltage value, (d) current value, (e) rotation speed, and (f) fuel injection amount when the impeller malfunctions is shown. Timing chart. The figure which shows the combination of the primary information and the secondary information when the impeller malfunction occurs. Changes in (a) fuel pressure, (b) integration term, (c) voltage value, (d) current value, (e) rotation speed, and (f) fuel injection amount when the suction filter is clogged. Timing chart to show. The figure which shows the combination of the primary information and the secondary information when the suction filter is clogged. Changes in (a) fuel pressure, (b) integration term, (c) voltage value, (d) current value, (e) rotation speed, and (f) fuel injection amount when an abnormality occurs in the pump control device Timing chart to show. The figure which shows the combination of the primary information and the secondary information when an abnormality occurs in a pump control device. The transition of (a) fuel pressure, (b) integration term, (c) voltage value, (d) current value, (e) rotation speed, and (f) fuel injection amount when an abnormality occurs in the pressure sensor is shown. Timing chart. (A) and (b) The figure which shows the combination of the primary information and the secondary information when an abnormality occurs in a pressure sensor. Changes in (a) fuel pressure, (b) integration term, (c) voltage value, (d) current value, (e) rotation speed, and (f) fuel injection amount when the input to the pump control device is interrupted. Timing chart showing. The figure which shows the combination of the primary information and the secondary information when the input to a pump control device is interrupted. A timing chart showing changes in (a) fuel pressure, (b) integration term, (c) voltage value, (d) current value, (e) rotation speed, and (f) fuel injection amount when fuel runs out. The figure which shows the combination of the primary information and the secondary information when a fuel shortage occurs. A flowchart showing a processing flow in a routine that starts timing of a period during which information acquisition processing is being executed. A flowchart showing a processing flow in a routine related to information acquisition processing and judgment processing. A flowchart showing a processing flow in a routine related to a determination process.

Hereinafter, embodiments of the control device of the fuel supply system will be described with reference to FIGS. 1 to 19.
FIG. 1 shows the configuration of a fuel supply system for an in-vehicle engine. The control device 100 of the present embodiment is applied to the fuel supply system of this in-vehicle engine.

As shown in FIG. 1, the fuel supply system to which the control device 100 is applied is provided with a fuel pump 52 installed in the fuel tank 51. The fuel pump 52 is an electric pump that rotates the impeller by a brushless motor. Further, the fuel supply system is provided with a fuel injection valve 44 provided in the intake port of the engine and a delivery pipe 71 to which the fuel injection valve 44 is connected. The engine equipped with this fuel supply system is an in-line 4-cylinder engine, and four fuel injection valves 44 are connected to the delivery pipe 71.

The fuel supply system is provided with a fuel passage 72 for sending fuel from the fuel pump 52 to the delivery pipe 71. That is, the fuel passage 72 and the delivery pipe 71 are fuel pipes from the fuel pump 52 to the fuel injection valve 44. The delivery pipe 71 is provided with a pressure sensor 132 that detects the fuel pressure Pf, which is the pressure of the fuel inside. The pressure sensor 132 indicates the fuel pressure Pf at a gauge pressure based on the atmospheric pressure.

The fuel pump 52 sucks the fuel in the fuel tank 51 through the suction filter 53 in response to the power supply and sends it out to the fuel passage 72. In the portion of the fuel passage 72 located inside the fuel tank 51, the pressure of the fuel sent to the fuel passage 72 by the fuel pump 52, that is, the fuel pressure Pf, which is the pressure of the fuel in the fuel pipe, is the default valve opening pressure. A relief valve 56 is provided to open the valve and relieve the fuel from the fuel pipe to the fuel tank 51 when the amount exceeds the above.

An engine including such a fuel supply system is controlled by the control device 100. The control device 100 is an engine control device and also controls the fuel supply system of the engine. That is, the control device 100 is also a control device for the fuel supply system.

The control device 100 includes an execution device 101 that executes various arithmetic processes, and a storage device 102 that stores control programs and data. Then, the control device 100 controls the engine including the control of the fuel supply system by reading and executing the program stored in the storage device 102 by the execution device 101.

The control device 100 is input with detection signals of various sensors for detecting the operating state of the engine. As shown in FIG. 1, the accelerator position sensor 142 inputs a detection signal of the driver's accelerator operation amount, and the vehicle speed sensor 141 inputs a vehicle speed detection signal which is the traveling speed of the vehicle. There is.

Further, detection signals of various other sensors are input to the control device 100. For example, as shown in FIG. 1, in the control device 100, in addition to the pressure sensor 132 that detects the fuel pressure Pf in the delivery pipe 71, the air flow meter 133, the crank position sensor 134, the cam position sensor 135, and the cooling water temperature sensor 136 is connected.

The air flow meter 133 detects the temperature of the air sucked into the cylinder through the intake passage of the engine and the intake air amount which is the mass of the sucked air. The crank position sensor 134 outputs a crank angle signal according to a change in the rotational phase of the crankshaft, which is the output shaft of the engine. The control device 100 calculates the engine speed, which is the number of revolutions of the crankshaft per unit time, based on the crank angle signal input from the crank position sensor 134.

The cam position sensor 135 outputs a cam angle signal according to a change in the rotation phase of the cam shaft. The cooling water temperature sensor 136 detects the cooling water temperature, which is the temperature of the cooling water of the engine.

Further, a fuel temperature sensor 137 that detects the fuel temperature Tf, which is the temperature of the fuel in the fuel tank 51, is also connected to the control device 100.
Further, the control device 100 is connected to a pump control device 200 that controls the rotation speed Np, which is the rotation speed of the impeller of the fuel pump 52 per unit time. The pump control device 200 increases or decreases the rotation speed Np by adjusting the power supplied to the fuel pump 52 by pulse width modulation based on a command from the control device 100. The pump control device 200 provides information on the voltage value Vp, which is the average value of the voltage in the power supply by pulse width modulation, the current value Ip, which is the current supplied to the fuel pump 52, and the rotation speed Np. Is sending to.

The control device 100 executes fuel injection amount control and fuel pressure control as part of engine control.
In controlling the fuel injection amount, the control device 100 first calculates the required injection amount Q, which is a required value of the fuel injection amount of the fuel injection valve 44, according to the engine operating state such as the engine speed and the engine load. Subsequently, the control device 100 calculates the valve opening time of the fuel injection valve 44 required for fuel injection for the required injection amount Q based on the detected value of the pressure sensor 132. Then, the control device 100 opens the fuel injection valve 44 of each cylinder to inject fuel for a period corresponding to the calculated valve opening time. Further, as a part of the fuel injection control, the control device 100 stops the fuel injection and stops the supply of the fuel to the combustion chamber of the engine during deceleration when the operation amount of the accelerator is "0". It also performs fuel cut control to reduce the fuel consumption rate.

Subsequently, the details of the fuel pressure control will be described. Fuel pressure control is performed for the following purposes. When the fuel sent from the fuel pump 52 and flowing through the fuel passage 72 receives the heat of the engine and becomes high in temperature, vapor is generated in the fuel passage 72, and the supply of fuel to the delivery pipe 71 may be delayed. The higher the fuel pressure, the higher the fuel vaporization temperature. Therefore, in order to prevent the generation of vapor in the fuel passage 72, the fuel supply amount by the fuel pump 52 may be increased to increase the fuel pressure Pf. However, if the fuel supply amount is increased, the power consumption of the fuel pump 52 will increase accordingly. Therefore, in fuel pressure control, in order to prevent the generation of vapor and maintain the fuel pressure Pf at a low pressure as much as possible, the fuel supply amount by the fuel pump 52 is adjusted to suppress the generation of vapor while suppressing the generation of vapor. It is preventing.

FIG. 2 shows a flow of processing related to fuel pressure control executed by the execution device 101 of the control device 100. As shown in FIG. 2, the fuel pressure control is performed through each of the required fuel pressure calculation process M200, the required rotation speed calculation process M210, and the fuel pressure feedback process M230.

In the required fuel pressure calculation process M200, the execution device 101 calculates the required fuel pressure Pf *, which is a target value of the fuel pressure Pf, based on the fuel temperature Tf detected by the fuel temperature sensor 137.

As shown by the alternate long and short dash line in FIG. 3, the control device 100 switches the required fuel pressure Pf * in three stages according to the fuel temperature Tf. In FIG. 3, in addition to the required fuel pressure Pf * shown by the two-dot chain line, the relationship between the saturated vapor pressure of the fuel and the fuel temperature is shown by a solid line, a one-dot chain line, and a broken line. The solid line shows the relationship between the saturated vapor pressure of gasoline and the fuel temperature, and the one-point chain line shows the saturated vapor pressure and fuel temperature of the E20 fuel containing 20% of ethanol in volume ratio among the mixed fuels of gasoline and ethanol. Shows the relationship with. Further, the broken line shows the relationship between the saturated vapor pressure of the M15 fuel containing 15% of methanol in the volume ratio and the fuel temperature among the mixed fuels of gasoline and methanol.

In the control device 100, the fuel temperature is such that the required fuel pressure Pf * does not fall below the saturated vapor pressure even when the fuel having the highest saturated vapor pressure is used among the fuels expected to be used. The higher the Tf, the higher the required fuel pressure Pf *. Specifically, in the required fuel pressure calculation process M200, the execution device 101 calculates "P1" as the required fuel pressure Pf * when the fuel temperature Tf is less than "T1" as shown in FIG. Then, when the fuel temperature Tf is equal to or higher than “T1” and less than “T2” higher than “T1”, the executing device 101 calculates “P2” higher than “P1” as the required fuel pressure Pf *. .. Further, when the fuel temperature Tf is "T2" or higher, the execution device 101 calculates "P3" as the required fuel pressure Pf *, which is higher than "P2" and slightly lower than the valve opening pressure Px of the relief valve 56. ..

In the required rotation speed calculation process M210, the execution device 101 performs the required rotation speed, which is a target value of the rotation speed Np, based on the required fuel supply amount Q * and the required fuel pressure Pf * calculated through the required fuel pressure calculation process M200. Calculate the number Np *. The required fuel supply amount Q * is a correction amount ΔQ calculated through the fuel pressure feedback process M230, which will be described later, with the required injection amount Q calculated through the required injection amount calculation process M100 executed as part of the fuel injection amount control. This is the corrected value.

In the control device 100, in the required rotation speed calculation process M210, the execution device 101 determines the rotation speed Np required to realize the required fuel pressure Pf * in consideration of the fuel consumption due to the execution of the fuel injection control. Calculated as the required rotation speed Np *.

Specifically, the execution device 101 calculates the required rotation speed Np * using the rotation speed calculation mapping data stored in the storage device 102. As shown in FIG. 2, the rotation speed calculation mapping data is an arithmetic map that outputs the required rotation speed Np * by inputting the required fuel pressure Pf * and the required fuel supply amount Q *. This calculation map is created so that the required rotation speed Np * can be calculated based on the result of an experiment using gasoline as a fuel, for example. FIG. 2 illustrates the contour lines of the required rotation speed Np *. In this calculation map, the higher the required fuel pressure Pf * and the larger the required fuel supply amount Q *, the larger the output required rotation speed Np *.

In the fuel pressure feedback process M230, the execution device 101 calculates the correction amount ΔQ based on the required fuel pressure Pf * calculated through the required fuel pressure calculation process M200 and the fuel pressure Pf detected by the pressure sensor 132. Then, the execution device 101 adds the calculated correction amount ΔQ to the required injection amount Q calculated through the required injection amount calculation process M100 to calculate the required fuel supply amount Q *. Specifically, this feedback control is a PID control that calculates a correction amount ΔQ by a proportional term, an integral term, and a differential term with respect to the deviation between the required fuel pressure Pf * and the fuel pressure Pf. In the fuel pressure feedback process M230, the execution device 101 increases the correction amount ΔQ when the fuel pressure Pf is smaller than the required fuel pressure Pf *. On the other hand, when the fuel pressure Pf is larger than the required fuel pressure Pf *, the execution device 101 reduces the correction amount ΔQ.

As a result, the required rotation speed Np * calculated by inputting the required fuel supply amount Q * corrected by the correction amount ΔQ calculated through the fuel pressure feedback process M230 is input to the pump control device 200. Then, the pump control device 200 feedback-controls the power supplied to the fuel pump 52 by pulse width modulation so as to realize the input required rotation speed Np *. That is, the power supply is reduced when the rotation speed Np is higher than the required rotation speed Np *, and supplied when the rotation speed Np is lower than the required rotation speed Np * so that the rotation speed Np matches the required rotation speed Np *. Increase power.

When the required rotation speed Np * is increased, the amount of fuel discharged from the fuel pump 52 increases per unit time, so that the fuel pressure Pf increases. On the other hand, if the required rotation speed Np * is reduced, the amount of fuel discharged from the fuel pump 52 per unit time is reduced, so that the fuel pressure Pf is lowered. That is, the fuel pressure feedback process M230 is a process of calculating the required fuel supply amount Q * by correcting the required injection amount Q so as to reduce the deviation between the fuel pressure Pf and the required fuel pressure Pf *.

By the way, as an abnormality of the fuel supply system, there may be an abnormality of various parts. For example, the impeller of the fuel pump 52 may malfunction, or the suction filter 53 may be clogged.

Since all of them affect the fuel supply, it is only detected that the fuel supply is excessive or deficient by detecting that the fuel pressure Pf deviates from the required fuel pressure Pf *. Then, it is not possible to identify which part of the abnormality is occurring.

In this fuel supply system, feedback control for the rotation speed Np by the pump control device 200 and feedback control based on the fuel pressure Pf by the fuel pressure feedback process M230 executed by the control device 100 are executed. That is, in this fuel supply system, the fuel pump 52 is controlled through these two feedback controls so that the fuel pressure Pf does not deviate from the required fuel pressure Pf *.

While an abnormality occurs in this fuel supply system and control is performed to absorb fluctuations in the fuel pressure Pf due to the abnormality through these two feedback controls, the fuel pressure Pf, the integration term I, the voltage value Vp, and the current The value Ip and the number of revolutions Np fluctuate. The mode of time-series change of these five values differs depending on the site where the abnormality occurs.

Therefore, in the control device 100, the execution device 101 absorbs fluctuations in the fuel pressure Pf due to an abnormality for a certain period of time after any of these five values deviates from the normal range, that is, through feedback control. Information acquisition processing is executed when the control for Then, in the information acquisition process, the storage device 102 stores the primary information and the secondary information, which are information about these five values at the time points separated in time series. Then, the execution device 101 performs a determination process based on the primary information and the secondary information stored in the storage device 102.

Hereinafter, the information acquisition process and the determination process executed by the execution device 101 of the control device 100 will be described with reference to FIGS. 4 to 19.
First, the normal range of five values of fuel pressure Pf, integration term I, voltage value Vp, current value Ip, and rotation speed Np will be described with reference to FIG. 4 showing an example in the case where no abnormality occurs. In FIG. 4, the normal range of each of these five values is shown by a broken line. In the example shown in FIG. 4, the fuel temperature Tf is constant and the required fuel pressure Pf * does not change.

As shown in FIG. 4A, in this case, the fuel pressure Pf is constant and does not change. The normal range for the fuel pressure Pf is a wide range in which it can be said that no abnormality has occurred in the pressure sensor 132 in consideration of the variation in the accuracy of the pressure sensor 132. It is set in the range of. In the case of the example shown in FIG. 4, since no abnormality has occurred, the value of the fuel pressure Pf is within the normal range.

Similarly, as shown in FIGS. 4 (b) to 4 (e), the normal range is the detection accuracy, calculation error, and sensitivity of each value in the integration term I, voltage value Vp, current value Ip, and rotation speed Np. It is set to a wide range where it can be said that no abnormality has occurred.

As shown in FIGS. 4 (c) to 4 (f), the voltage value Vp, the current value Ip, and the rotation speed Np change in the same manner as the fuel injection amount. This is because the required fuel pressure Pf * is constant, so in order to match the fuel pressure Pf with the required fuel pressure Pf *, the required injection amount Q is increased or decreased, that is, the fuel pump 52 is driven according to the increase or decrease in the fuel injection amount. This is because it is necessary to increase or decrease the amount to increase or decrease the fuel supply amount. Therefore, the normal range of the voltage value Vp, the current value Ip, and the rotation speed Np is set as a range of several percent above and below the median value of each value calculated based on the fuel injection amount.

As shown in FIG. 4 (b), the integral term I changes at a constant value and does not fluctuate. This is because, in the example shown in FIG. 4, the fuel pressure Pf does not fluctuate and the state of matching the required fuel pressure Pf * continues. Therefore, the integral term I is also within the normal range.

Next, under the same conditions as the example shown in FIG. 4, five values of fuel pressure Pf, integral term I, voltage value Vp, current value Ip, and rotation speed Np when an abnormality occurs in the fuel supply system The transition is shown, and the primary information and the secondary information stored in the storage device 102 in the information acquisition process will be described.

FIG. 5 shows the transition of five values of the fuel pressure Pf, the integration term I, the voltage value Vp, the current value Ip, and the rotation speed Np when the impeller malfunction occurs in the fuel pump 52. Note that FIG. 5 (f) shows the transition of the fuel injection amount similar to that of FIG. 4 (f), and shows that the transition is under the same conditions as the example shown in FIG. When a malfunction of the impeller occurs, such as when a foreign substance is caught in the impeller, the resistance when rotating the impeller increases, so that the rotation speed of the impeller decreases. Therefore, as shown in FIGS. 5A and 5E, the rotation speed Np decreases, and the fuel supply amount becomes insufficient, so that the fuel pressure Pf decreases.

As a result, the rotation speed Np or the fuel pressure Pf first deviates from the normal range. In the control device 100, the information acquisition process is started at the time when any of the above five values deviates from the normal range, that is, at the time t10 in FIG.

After that, as shown in FIGS. 5 (c) and 5 (d), the power supplied to the fuel pump 52 is increased by the feedback control of the rotation speed Np by the pump control device 200, and the voltage value Vp and the current value Ip are increased. Increase. As a result, the voltage value Vp or the current value Ip deviates from the normal range. In the control device 100, among the above five values, the value different from the value deviating from the normal range when the information acquisition process is started deviates from the normal range, that is, in FIG. 5, the time t21 is the above. Information on the magnitude relationship between the five values of and the normal range is stored as primary information.

As shown in FIGS. 5A and 5E, in the case of a malfunction of the impeller that makes it difficult for the impeller to rotate, when the voltage value Vp and the current value Ip increase, the force for driving the impeller increases. The rotation speed Np, which is the rotation speed of the impeller, recovers, and the fuel pressure Pf also recovers quickly. Therefore, as shown in FIG. 5B, the integral term I in the feedback control of the fuel pressure Pf hardly changes and does not deviate from the normal range.

Therefore, as shown in FIG. 6, in this case, the primary information is information indicating that the integral term I is within the normal range and the voltage value Vp or the current value Ip is higher than the normal range.
At time t30, when a predetermined time has elapsed since the information acquisition process was started at time t10, information on the magnitude relationship between the above five values at the time of time t30 and the normal range is stored as secondary information.

As shown in FIG. 5, the feedback control of the rotation speed Np by the pump control device 200 recovers the rotation speed of the impeller, and when the fuel pressure Pf recovers, the voltage value Vp and the current value Ip by the feedback control of the rotation speed Np The growth stops.

Therefore, at time t30, the fuel pressure Pf, the integral term I, and the rotation speed Np are within the normal range, and the voltage value Vp and the current value Ip are higher than the normal range.
Therefore, as shown in FIG. 6, the secondary information stored when the information acquisition process is terminated at time t30 is such that the fuel pressure Pf, the integral term I, and the rotation speed Np are within the normal range, and the voltage value Vp and the current value. This is information indicating that Ip is higher than the normal range.

In the control device 100, the primary information and the secondary information shown in FIG. 6 are stored in the storage device 102 in advance as determination data for determining that the impeller malfunction has occurred. In the determination process executed by the execution device 101, the primary information and the secondary information stored through the information acquisition process during the operation of the fuel supply system are collated with the determination data. Then, when the data matches the determination data shown in FIG. 6, it is determined that the impeller is malfunctioning. In FIG. 6, "-" is entered in the columns of the fuel pressure Pf and the rotation speed Np, indicating that the values of the fuel pressure Pf and the rotation speed Np are irrelevant for the primary information. Further, the columns of the voltage value Vp and the current value Ip are shown in parentheses, indicating that either one of the voltage value Vp and the current value Ip should match the determination data.

FIG. 7 shows the transition of five values of the fuel pressure Pf, the integral term I, the voltage value Vp, the current value Ip, and the rotation speed Np when the suction filter 53 is clogged. Note that FIG. 7 (f) shows the transition of the fuel injection amount similar to that of FIG. 4 (f), and shows that the transition is under the same conditions as the example shown in FIG. When the suction filter 53 provided at the suction port of the fuel pump 52 is clogged, it becomes difficult to pump the fuel. Therefore, even if the impeller is rotating at a rotation speed corresponding to the required rotation speed Np *, the fuel supply amount is insufficient and the fuel pressure Pf is lowered.

Therefore, as shown in FIG. 7A, in this case, the fuel pressure Pf first deviates from the normal range. Then, the information acquisition process is started from the time t10. As shown in FIG. 7, clogging that suddenly lowers the fuel pressure Pf occurs because sludge due to rust or the like is accumulated in the fuel tank 51, and the sludge is once caused by the shaking of the fuel. For example, when the fuel is sucked up by the fuel pump 52.

In this case, the impeller is rotating at a rotation speed commensurate with the required rotation speed Np *. Therefore, as shown in FIGS. 7 (c) to 7 (e), the voltage value Vp, the current value Ip, and the rotation speed Np change within the normal range. On the other hand, since the state in which the fuel pressure Pf is lower than the required fuel pressure Pf * continues, the integral term I in the feedback control of the fuel pressure Pf gradually increases as shown in FIG. 7B. As a result, at time t22, the integral term I deviates from the normal range, and information on the magnitude relationship between the above five values at time t22 and the normal range is stored as primary information.

As shown in FIG. 8, in this case, the primary information is that the fuel pressure Pf is lower than the normal range, the voltage value Vp, the current value Ip, and the rotation speed Np are within the normal range, and the integral term I is lower than the normal range. It will be information indicating that it is expensive.

At time t30, when a predetermined time has elapsed since the information acquisition process was started at time t10, information on the magnitude relationship between the above five values at the time of time t30 and the normal range is stored as secondary information.

As the fuel pressure Pf continues to be below the required fuel pressure and the required fuel supply amount Q * is increased through the feedback control of the fuel pressure Pf, the required rotation speed Np * increases. As a result, the voltage value Vp, the current value Ip, and the rotation speed Np increase as shown after the time t22 in FIGS. 7 (c) to 7 (e). As a result, the amount of fuel supplied increases even when the suction filter 53 is clogged. Then, as shown in FIG. 7A, the fuel pressure Pf gradually recovers. When the fuel pressure Pf is recovered in this way, the increase in the integral term I due to the feedback control of the fuel pressure Pf and the increase in the voltage value Vp, the current value Ip, and the rotation speed Np are stopped.

Therefore, at time t30, the fuel pressure Pf is within the normal range, and the integral term I, the voltage value Vp, the current value Ip, and the rotation speed Np are higher than the normal range.
Therefore, as shown in FIG. 8, the secondary information stored when the information acquisition process is terminated at time t30 is such that the fuel pressure Pf is within the normal range and the integral term I, the voltage value Vp, the current value Ip, and the rotation speed. This is information indicating that Np is higher than the normal range.

In the control device 100, the primary information and the secondary information shown in FIG. 8 are stored in the storage device 102 in advance as determination data for determining that the suction filter 53 is clogged. In the determination process executed by the execution device 101, the primary information and the secondary information stored through the information acquisition process during the operation of the fuel supply system are collated with the determination data. Then, when the data matches the determination data shown in FIG. 8, it is determined that the suction filter 53 is clogged.

FIG. 9 shows the transition of five values of the fuel pressure Pf, the integral term I, the voltage value Vp, the current value Ip, and the rotation speed Np when an abnormality occurs in the pump control device 200. Note that FIG. 9 (f) shows the transition of the fuel injection amount similar to that of FIG. 4 (f), and shows that the transition is under the same conditions as the example shown in FIG. If an abnormality occurs in the pump control device 200, the fuel pump 52 cannot be driven properly, and the voltage value Vp, the current value Ip, and the rotation speed of the impeller may be significantly reduced.

Therefore, when such an abnormality occurs, as shown in FIGS. 9 (c) to 9 (e), any one of the voltage value Vp, the current value Ip, and the rotation speed Np first deviates from the normal range. Then, the information acquisition process is started from the time t10.

When an abnormality has occurred in the pump control device 200 and such a state occurs, the feedback control of the rotation speed Np by the pump control device 200 cannot be performed. Therefore, the voltage value Vp, the current value Ip, and the rotation speed Np will continue to change at extremely low levels. As a result, the fuel pressure Pf gradually decreases as shown in FIG. 9A. As a result, at time t23, the fuel pressure Pf deviates from the normal range, and information on the magnitude relationship between the above five values at time t23 and the normal range is stored as primary information. At this point, the integral term I has not increased so much.

As shown in FIG. 10, in this case, the primary information indicates that the fuel pressure Pf, the voltage value Vp, the current value Ip, and the rotation speed Np are lower than the normal range and the integral term I is within the normal range. It becomes information.

At time t30, when a predetermined time has elapsed since the information acquisition process was started at time t10, information on the magnitude relationship between the above five values at the time of time t30 and the normal range is stored as secondary information.

As shown in FIG. 9B, after the time t23, the fuel pressure Pf continues to be below the required fuel pressure, so that the integral term I becomes large. In this case, the required fuel supply amount Q * is increased and the required rotation speed Np * is also increased by the feedback control of the fuel pressure Pf. However, when an abnormality has occurred in the pump control device 200, the voltage value Vp, the current value Ip, and the rotation speed Np are shown in FIGS. 9 (a) and 9 (c) to 9 (e). Continues to remain at a significantly lower level and the fuel pressure Pf does not recover. Therefore, at time t30, the fuel pressure Pf, the voltage value Vp, the current value Ip, and the rotation speed Np are lower than the normal range, and the integral term I is higher than the normal range.

Therefore, as shown in FIG. 10, the secondary information stored when the information acquisition process is terminated at time t30 is such that the fuel pressure Pf, the voltage value Vp, the current value Ip, and the rotation speed Np are lower than the normal range. This is information indicating that the integration term I is higher than the normal range.

In the control device 100, the primary information and the secondary information shown in FIG. 10 are stored in the storage device 102 in advance as determination data for determining that an abnormality has occurred in the pump control device 200. In the determination process executed by the execution device 101, the primary information and the secondary information stored through the information acquisition process during the operation of the fuel supply system are collated with the determination data. Then, when the data matches the determination data shown in FIG. 10, it is determined that an abnormality has occurred in the pump control device 200.

FIG. 11 shows fuel pressure Pf, integration term I, voltage value Vp, when an abnormality occurs in the pressure sensor 132 and the pressure sensor 132 continues to output a signal indicating a pressure lower than the actual fuel pressure. The transition of five values of the current value Ip and the rotation speed Np is shown. Note that FIG. 11 (f) shows the transition of the fuel injection amount similar to that of FIG. 4 (f), and shows that the transition is under the same conditions as the example shown in FIG. When such an abnormality occurs, the fuel pressure Pf first deviates from the normal range.

Therefore, in this case, as shown in FIG. 11A, the value of the fuel pressure Pf first decreases and deviates from the normal range. Then, the information acquisition process is started from the time t10.

In this case, since the state in which the fuel pressure Pf is lower than the required fuel pressure continues, the integral term I in the feedback control of the fuel pressure Pf gradually increases as shown in FIG. 11B. As a result, at time t24, the integral term I deviates from the normal range, and information on the magnitude relationship between the above five values at time t24 and the normal range is stored as primary information.

As shown in FIG. 12A, in this case, the primary information is that the fuel pressure Pf is lower than the normal range, the voltage value Vp, the current value Ip, and the rotation speed Np are within the normal range, and the integral term I is normal. It is information indicating that it is higher than the range.

At time t30, when a predetermined time has elapsed since the information acquisition process was started at time t10, information on the magnitude relationship between the above five values at the time of time t30 and the normal range is stored as secondary information.

As the fuel pressure Pf continues to be below the required fuel pressure and the required fuel supply amount Q * is increased through the feedback control of the fuel pressure Pf, the required rotation speed Np * increases, and FIG. 11 (Fig. 11) c) As shown in FIGS. 11 (e), the voltage value Vp, the current value Ip, and the rotation speed Np increase. However, when an abnormality occurs in the pressure sensor 132, the voltage value Vp, the current value Ip, and the rotation speed Np increase, and the pressure increases even if the actual fuel pressure increases due to the increase in the fuel supply amount. The signal output by the sensor 132 does not change. Therefore, as shown in FIG. 11A, the value of the fuel pressure Pf does not recover.

Therefore, at time t30, the fuel pressure Pf is lower than the normal range, and the integral term I, the voltage value Vp, the current value Ip, and the rotation speed Np are higher than the normal range.
Therefore, as shown in FIG. 12A, the secondary information stored when the information acquisition process is terminated at time t30 is such that the fuel pressure Pf is lower than the normal range and the integral term I, the voltage value Vp, and the current. It is information indicating that the value Ip and the rotation speed Np are higher than the normal range.

By the way, when an abnormality has occurred in the pressure sensor 132, contrary to the state shown in FIG. 11, the pressure sensor 132 may continue to output a signal indicating a pressure higher than the normal range. .. In this case, contrary to the example shown in FIG. 11, the information acquisition process is started by first increasing the value of the fuel pressure Pf and deviating from the normal range.

In this case, since the state in which the fuel pressure Pf exceeds the required fuel pressure Pf * continues, the integral term I in the feedback control of the fuel pressure Pf gradually becomes smaller and becomes a negative value. As a result, the integral term I deviates from the normal range, and information on the magnitude relationship between the above five values and the normal range at this time is stored as primary information.

As shown in FIG. 12B, in this case, the primary information is that the fuel pressure Pf is higher than the normal range, the integral term I is lower than the normal range, and the voltage value Vp, the current value Ip, and the rotation speed Np are. It is information indicating that it is within the normal range.

As the fuel pressure Pf continues to exceed the required fuel pressure Pf * and the required fuel supply amount Q * decreases through the feedback control of the fuel pressure Pf, the required rotation speed Np * decreases and the voltage The value Vp, the current value Ip, and the rotation speed Np decrease. However, when an abnormality occurs in the pressure sensor 132, the voltage value Vp, the current value Ip, and the rotation speed Np decrease, and the pressure decreases even if the actual fuel pressure decreases due to the decrease in the fuel supply amount. The signal output by the sensor 132 does not change. Therefore, the value of the fuel pressure Pf does not decrease even in this case. Therefore, as shown in FIG. 12B, the secondary information stored when the information acquisition process is terminated after a certain period of time has the integral term I, the voltage value Vp, the current value Ip, and the rotation speed Np. It is information indicating that the fuel pressure Pf is lower than the normal range and higher than the normal range.

In the control device 100, the primary information and the secondary information shown in FIG. 12 are stored in the storage device 102 in advance as determination data for determining that an abnormality has occurred in the pressure sensor 132. In the determination process executed by the execution device 101, the primary information and the secondary information stored through the information acquisition process during the operation of the fuel supply system are collated with the determination data. Then, when it matches with the determination data shown in FIG. 12, that is, when it matches with any of the determination data shown in FIG. 12 (a) and the determination data shown in FIG. 12 (b), the pressure is applied. It is determined that an abnormality has occurred in the sensor 132.

FIG. 13 shows the fuel pressure Pf, the integration term I, and the voltage when the input of the required rotation speed Np * to the pump control device 200 is interrupted due to the interruption of communication from the control device 100 to the pump control device 200. The transition of five values of the value Vp, the current value Ip, and the rotation speed Np is shown. Note that FIG. 13 (f) shows the transition of the fuel injection amount similar to that of FIG. 4 (f), and shows that the transition is under the same conditions as the example shown in FIG. When the input of the required rotation speed Np * to the pump control device 200 is interrupted, the pump control device 200 does not drive the fuel pump 52. Therefore, the voltage value Vp, the current value Ip, and the rotation speed Np become "0".

Therefore, when such an abnormality occurs, as shown in FIGS. 13 (c) to 13 (e), the voltage value Vp, the current value Ip, and the rotation speed Np first deviate from the normal range. Then, the information acquisition process is started from the time t10.

In such a state, the fuel pump 52 is stopped, so that the fuel pressure Pf gradually decreases as shown in FIG. 13 (a). As a result, at time t25, the fuel pressure Pf deviates from the normal range, and information on the magnitude relationship between the above five values at time t25 and the normal range is stored as primary information. At this point, the integral term I has not increased so much.

Therefore, as shown in FIG. 14, the primary information indicates that the fuel pressure Pf is lower than the normal range, the integral term I is within the normal range, and the voltage value Vp, the current value Ip, and the rotation speed Np are “0”. It becomes the information to show.

At time t30, when a predetermined time has elapsed since the information acquisition process was started at time t10, information on the magnitude relationship between the above five values at the time of time t30 and the normal range is stored as secondary information.

As shown in FIG. 13B, after the time t25, the fuel pressure Pf continues to be below the required fuel pressure, so that the integral term I becomes large. In this case, the required fuel supply amount Q * increases and the required rotation speed Np * also increases due to the feedback control of the fuel pressure. However, when the input of the required rotation speed Np * to the pump control device 200 is interrupted, the pump control device 200 does not drive the fuel pump 52. Therefore, as shown in FIGS. 13 (c) to 13 (e), the voltage value Vp, the current value, and the rotation speed of the impeller remain “0” and do not change. Therefore, as shown in FIG. 13A, the fuel pressure Pf does not recover. Therefore, at time t30, the fuel pressure Pf is lower than the normal range, the integral term I is higher than the normal range, and the voltage value Vp, the current value Ip, and the rotation speed Np are “0”.

Therefore, as shown in FIG. 14, the secondary information stored when the information acquisition process is terminated at time t30 has a fuel pressure Pf lower than the normal range, an integral term I higher than the normal range, and a voltage value. This is information indicating that Vp, the current value Ip, and the rotation speed Np are "0".

In the control device 100, the primary information and the secondary information shown in FIG. 14 are stored in the storage device 102 in advance as determination data for determining that the input of the required rotation speed Np * to the pump control device 200 is interrupted. I remember. In the determination process executed by the execution device 101, the primary information and the secondary information stored through the information acquisition process during the operation of the fuel supply system are collated with the determination data. Then, when the data matches the determination data shown in FIG. 14, it is determined that the input of the required rotation speed Np * to the pump control device 200 is interrupted.

FIG. 15 shows the transition of five values of the fuel pressure Pf, the integral term I, the voltage value Vp, the current value Ip, and the rotation speed Np when the fuel runs out. Note that FIG. 15 (f) shows the transition of the fuel injection amount similar to that of FIG. 4 (f), and shows that the transition is under the same conditions as the example shown in FIG. When the fuel runs out, the fuel pump 52 sucks in air and spins, so that the load on the motor of the fuel pump 52 is reduced. Then, the voltage value Vp and the current value Ip decrease through the feedback of the rotation speed Np by the pump control device 200.

Therefore, as shown in FIGS. 15 (c) and 15 (d), the voltage value Vp or the current value Ip first deviates from the normal range. Then, the information acquisition process is started from the time t10.

In such a state, the fuel supply by the fuel pump 52 is delayed due to the fuel shortage, so that the fuel pressure Pf gradually decreases as shown in FIG. 15A. As a result, at time t26, the fuel pressure Pf deviates from the normal range, and information on the magnitude relationship between the above five values at time t26 and the normal range is stored as primary information. At this point, the integral term I has not increased so much.

Therefore, as shown in FIG. 16, the primary information is information indicating that the fuel pressure Pf, the voltage value Vp, and the current value Ip are lower than the normal range, and the integral term I and the rotation speed Np are within the normal range. ..

At time t30, when a predetermined time has elapsed since the information acquisition process was started at time t10, information on the magnitude relationship between the above five values at the time of time t30 and the normal range is stored as secondary information.

As shown in FIG. 15B, after the time t26, the fuel pressure Pf continues to be below the required fuel pressure, so that the integral term I becomes large. Due to the feedback control of the fuel pressure Pf, the required fuel supply amount Q * is increased, and the required rotation speed Np * is also increased. As a result, the voltage value Vp, the current value Ip, and the rotation speed Np increase as shown in FIGS. 15 (c) to 15 (e) through the feedback control of the rotation speed Np by the pump control device 200.

However, when the fuel runs out, the fuel supply amount does not increase even if the rotation speed Np is increased. Therefore, as shown in FIG. 15A, the fuel pressure Pf does not recover in this case. At time t30, the fuel pressure Pf is lower than the normal range, and the integral term I and the rotation speed Np are higher than the normal range.

Therefore, as shown in FIG. 16, in the secondary information stored when the information acquisition process is terminated at time t30, the fuel pressure Pf is lower than the normal range, and the integral term I and the rotation speed Np are lower than the normal range. It is information that shows that it is expensive.

In the control device 100, the primary information and the secondary information shown in FIG. 16 are stored in the storage device 102 in advance as determination data for determining that the pump control device 200 has run out of fuel. In the determination process executed by the execution device 101, the primary information and the secondary information stored through the information acquisition process during the operation of the fuel supply system are collated with the determination data. Then, when the data matches the determination data shown in FIG. 16, it is determined that the fuel has run out. In FIG. 16, "-" is entered in the columns of the voltage value Vp and the current value Ip, indicating that the values of the voltage value Vp and the current value Ip do not matter for the secondary information.

Next, a series of processing flows related to the information acquisition processing and the determination processing executed by the execution device 101 of the control device 100 will be described.
The execution device 101 of the control device 100 repeatedly executes a series of processes shown in FIG. 17 while the fuel supply system is operating, and determines the timing when any of the above five values deviates from the normal range. Starts the time counting of the elapsed time since the detection and the start of the information acquisition process. The routine shown in FIG. 17 is repeatedly executed by the execution device 101 on the condition that the determination process is not performed and the time counting of the elapsed time is not executed when the fuel supply system is operating. ..

As shown in FIG. 17, when this routine is started, the execution device 101 of the control device 100 first determines whether or not any of the above five values deviates from the normal range in the process of step S100. To judge.

If it is determined in step S100 that any of the above five values deviates from the normal range (step S100: YES), the execution device 101 advances the process to step S110. Then, the execution device 101 starts timing by the timer in the process of step S110, and temporarily ends this routine.

On the other hand, if it is determined in step S100 that none of the above five values deviates from the normal range (step S100: NO), the process of step S110 is not executed. Terminate the routine once.

By repeatedly executing this routine, it is possible to detect the timing when any of the above five values deviates from the normal range and start timing.
When the execution device 101 starts timing through the routine shown in FIG. 17, the execution device 101 repeatedly executes the routine shown in FIG. This routine is a routine related to information acquisition processing and determination processing, and is repeatedly executed by the execution device 101 while timekeeping by the timer is being executed. In the control device 100, the start timing of the information acquisition process is when the process of FIG. 18 is executed for the first time after the time counting by the timer is started.

As shown in FIG. 18, when this routine is started, the execution device 101 first determines in the process of step S200 whether or not the time measured by the timer is less than the specified time.

If it is determined in the process of step S200 that the time measured by the timer is less than the specified time (step S200: YES), the execution device 101 advances the process to step S210. Then, in the process of step S210, the execution device 101 normally has a value different from the value that deviates from the normal range when an affirmative determination is made in the process of step S100 in the routine of FIG. 17 among the above five values. Determine if the range is out of range.

If it is determined in the process of step S210 that the normal range is not deviated (step S210: NO), the execution device 101 temporarily terminates this routine as it is. On the other hand, if it is determined in the process of step S210 that the process deviates from the normal range (step S210: YES), the execution device 101 advances the process to step S220.

In the process of step S220, the execution device 101 determines whether or not the primary information has been stored in the information acquisition process this time.
If it is determined in the process of step S220 that the primary information has not yet been stored in the information acquisition process this time (step S220: NO), the execution device 101 advances the process to step S230. In the process of step S230, the execution device 101 stores in the storage device 102 as primary information information on the magnitude relationship with respect to the normal range for the above five values at that time. Then, the execution device 101 temporarily terminates this routine.

On the other hand, when it is determined in the process of step S220 that the primary information in the current information acquisition process is already stored (step S220: YES), the execution device 101 temporarily terminates this routine as it is.

When the routine of FIG. 18 is repeated and the time measured by the timer reaches the specified time, it is determined in the process of step S200 that the time measured by the timer is equal to or longer than the specified time.

If it is determined in the process of step S200 that the time counting time by the timer is equal to or longer than the specified time (step S200: NO), the execution device 101 advances the process to step S240. In the process of step S240, the execution device 101 resets the timer and ends the time counting by the timer. As a result, when the current information acquisition process is terminated and this routine is terminated, this routine is not repeated, and the routine shown in FIG. 17 is executed again on condition that the determination process is not executed.

The execution device 101 then proceeds to step S250. In the process of step S250, the execution device 101 determines whether or not the primary information has been stored in the current information acquisition process, as in the process of step S220.

If it is determined in the process of step S250 that the primary information has not yet been stored in the current information acquisition process (step S250: NO), the execution device 101 ends this routine as it is. In this case, although one of the above five values once deviated from the normal range, the default time elapsed without the other values deviating from the normal range, resulting in an abnormality. Terminates this routine without determining. In this case, the routine of FIG. 17 will be repeatedly executed again.

On the other hand, if it is determined in the process of step S250 that the primary information is already stored (step S250: YES), the execution device 101 proceeds to the process to step S260. Then, in the process of step S260, the execution device 101 stores the information of the magnitude relation with respect to the normal range for the above five values at that time in the storage device 102 as secondary information.

Then, the execution device 101 advances the process to step S300 and executes the determination process shown in FIG.
As shown in FIG. 19, when the routine of this determination process is started, the execution device 101 first, in the process of step S310, stores the acquired data consisting of the primary information and the secondary information acquired through the information acquisition process this time, and the storage device. The determination data stored in advance in 102 is collated. Then, the execution device 101 advances the process to step S320.

In the process of step S320, the execution device 101 determines whether or not the determination data includes data that matches the acquired data.
If it is determined in the process of step S320 that the determination data includes data that matches the acquired data (step S320: YES), the execution device 101 advances the process to step S330. Then, in the process of step S330, the execution device 101 determines that an abnormality corresponding to the matched determination data has occurred, and outputs a specific abnormality code corresponding to the abnormality. For example, when the determination data corresponding to the malfunction of the impeller matches the acquired data, a specific abnormality code indicating that the malfunction of the impeller has occurred is output and stored in the storage device 102.

As shown in FIG. 1, the control device 100 is connected to a warning display unit 110 that displays an icon as information indicating that an abnormality has occurred and notifies the occupant that an abnormality has occurred. ing. When the execution device 101 determines the abnormality, the control device 100 causes the warning display unit 110 to display an icon indicating that an abnormality has occurred. When the specific abnormality code is output through the process of step S330, the control device 100 causes the warning display unit 110 to display an icon corresponding to the type of the specific abnormality code, and the occupant generates the specified abnormality through the determination process. Notify that you are.

On the other hand, in the process of step S230, when it is determined that there is no data matching the acquired data in the determination data (step S320: NO), the execution device 101 advances the process to step S340. .. Then, in the process of step S340, the execution device 101 outputs a general abnormality code indicating that an abnormality has occurred in the fuel supply system and stores it in the storage device 102. This general abnormality code is an abnormality code indicating that an abnormality has been detected in the fuel supply system, although the location where the abnormality has occurred has not been identified. When a general abnormality code is output through the process of step S340, the control device 100 displays an icon corresponding to the general abnormality code on the warning display unit 110, and informs the occupant that an abnormality has occurred in the fuel supply system. Notify.

When the process of step S330 or step S340 is completed and the determination process of S300 is completed in this way, the execution device 101 ends the routine shown in FIG.
The operation of this embodiment will be described.

In the above fuel supply system, feedback control for the rotation speed Np by the pump control device 200 and feedback control based on the fuel pressure Pf by the fuel pressure feedback process executed by the control device 100 are executed. In such a fuel supply system, the fuel pump 52 is controlled through these two feedback controls so that the fuel pressure Pf does not deviate from the required fuel pressure Pf *.

While an abnormality occurs in the fuel supply system and the control for absorbing the fluctuation of the fuel pressure Pf due to the abnormality is performed through these two feedback controls, the above five values fluctuate. The mode of time-series change of the above five values differs depending on the location where the abnormality occurs.

On the other hand, in the control device 100, the execution device 101 deviates from the normal range of any of the above five values for a certain period of time, that is, through feedback control, the fuel pressure Pf due to an abnormality. The information acquisition process is executed when the control for absorbing the fluctuation of is performed. Then, in the information acquisition process, the storage device 102 stores the primary information and the secondary information, which are information about the above five values at the time points separated in time series. Then, the execution device 101 performs a determination process based on the primary information and the secondary information stored in the storage device 102.

The effect of this embodiment will be described.
(1) In the determination process, it is possible to reflect the mode of time-series change of the above five values. Therefore, according to the control device 100, it is possible to identify the portion where the abnormality is occurring.

(2) Even if the fuel pressure Pf recovers through feedback control such as impeller malfunction or clogging of the suction filter 53, the abnormality can be detected and the portion can be specified. Therefore, the fuel pressure Pf cannot be properly controlled, and repair can be urged before the condition becomes so serious that the operation cannot be continued.

As a result, it is possible to carry out appropriate repairs before the driving cannot be continued to prevent the situation where the driving cannot be continued on the road.
(3) In the control device 100, the storage device 102 stores determination data in which the combination of the primary information and the secondary information and the relationship between the occurrence site of the abnormality are associated with each other. According to such a configuration, the primary information and the secondary information can be collated with the determination data, and the portion where the abnormality occurs can be easily identified.

(4) According to the control device 100 described above, it can be determined that the impeller malfunction has occurred based on the primary information and the secondary information.
(5) According to the control device 100 described above, it can be determined that the suction filter 53 is clogged based on the primary information and the secondary information.

(6) According to the control device 100 described above, it can be determined that an abnormality has occurred in the pump control device 200 based on the primary information and the secondary information.
(7) According to the control device 100 described above, it can be determined that an abnormality has occurred in the pressure sensor 132 based on the primary information and the secondary information.

(8) According to the above-mentioned control device 100, it can be determined that the input of the required rotation speed Np * to the pump control device 200 is interrupted based on the primary information and the secondary information.
(9) According to the above-mentioned control device 100, it can be determined that the fuel has run out based on the primary information and the secondary information.

This embodiment can be modified and implemented as follows. The present embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
-As described above, if the abnormality can be detected and the part can be identified, the repair can be performed efficiently. For example, if the identified abnormality information is transmitted to the maintenance shop together with the vehicle identification code through the in-vehicle communication device, the parts can be prepared before the goods are stored in the maintenance shop. In particular, in the case of a vehicle used to provide services such as ride sharing and car sharing, such an embodiment can shorten the maintenance time of the vehicle and shorten the downtime, which is the time when the vehicle cannot operate. ..

-The method of determination processing is not limited to the method of informationing the determination data and the acquired data stored in advance. For example, the determination process may be performed by using a function that inputs the primary information and the secondary information and outputs the determination result. For example, it is conceivable to execute a determination process for identifying the type of abnormality using a machine-learned model that inputs primary information and secondary information and outputs a determination result.

The mapping data stored in the storage device 102 does not have to be an arithmetic map. For example, it may be a function.
-Although the example in which the fuel temperature Tf is detected by the fuel temperature sensor 137 is shown, the fuel temperature Tf may be obtained by estimation.

-The content of the determination data is not limited to that shown in the above embodiment. For example, any of the determination data shown in the above embodiment may be omitted. Even in that case, the type of abnormality can be specified for the type of abnormality included in the determination data. Further, if the site can be specified by the combination of the primary information and the secondary information, determination data other than those illustrated in the above embodiment may be stored.

-The determination data shown in FIG. 12 (a) and the determination data shown in FIG. 12 (b) are stored as the determination data for determining that an abnormality has occurred in the pressure sensor 132. Although an example is shown, only one of these may be stored in the storage device 102. Even in this case, if the acquired data matching the stored determination data is stored in the storage device 102, it is possible to determine the occurrence of an abnormality in the pressure sensor 132.

The control device 100 is (A) one or more processors that execute various processes according to a computer program (software), and (B) an integrated circuit (ASIC) for a specific application that executes at least a part of the various processes. It can be configured as a circuitry including one or more dedicated hardware circuits such as (C) a combination thereof. The processor includes a CPU and a storage device such as a RAM and a ROM, and the storage device stores a program code or an instruction configured to cause the CPU to execute a process. A storage device, or computer-readable medium, includes any available medium accessible by a general purpose or dedicated computer.

44 ... Fuel injection valve 51 ... Fuel tank 52 ... Fuel pump 53 ... Suction filter 56 ... Relief valve 71 ... Delivery pipe 72 ... Fuel passage 100 ... Control device 101 ... Execution device 102 ... Storage device 110 ... Warning display 132 ... Pressure sensor 133 ... Air flow meter 134 ... Crank position sensor 135 ... Cam position sensor 136 ... Cooling water temperature sensor 137 ... Fuel temperature sensor 141 ... Vehicle speed sensor 142 ... Accelerator position sensor 200 ... Pump control device

Claims (9)

An electric fuel pump, a fuel injection valve for injecting fuel, a pressure sensor for detecting the fuel pressure in the fuel pipe from the fuel pump to the fuel injection valve, and a voltage value and a current value in the fuel pump. It is applied to a fuel supply system including a pump control device that feedback-controls the power supply to the fuel pump by pulse width modulation so as to detect the rotation speed of the impeller per unit time and realize the required rotation speed.
The required rotation speed calculation process for calculating the required rotation speed based on the required fuel supply amount and the required fuel pressure, and the deviation between the detected value of the fuel pressure detected by the pressure sensor and the required fuel pressure are reduced. It is a control device of a fuel supply system including an execution device for executing a fuel pressure feedback process for correcting a required fuel supply amount and outputting the required rotation speed to the pump control device, and a storage device.
In the execution device, one of the five values of the fuel pressure detected by the pressure sensor, the integration term in the fuel pressure feedback process, the voltage value, the current value, and the rotation speed is within the normal range. It is a process that is executed for a certain period of time from the time of deviation, and when a value different from the value that deviates from the normal range when the process is started out of the above five values deviates from the normal range, the above-mentioned at that time. Information on the magnitude relationship between the five values and the normal range is stored in the storage device as primary information, and when the processing is completed after a certain period of time has passed, the normal range for the five values at that time is used. An abnormality in the fuel supply system based on an information acquisition process that stores information related to the magnitude of the above as secondary information in the storage device, and the primary information and the secondary information stored in the storage device in the information acquisition process. A control device for a fuel supply system that executes a judgment process that identifies the presence or absence of information and the location of an abnormality. The storage device stores determination data in which the combination of the primary information and the secondary information and the relationship between the occurrence site of the abnormality are associated with each other.
In the determination process, the execution device collates the primary information and the secondary information stored in the information acquisition process with the determination data, and the presence or absence of an abnormality and the occurrence of an abnormality in the fuel supply system are generated. The control device for a fuel supply system according to claim 1, wherein a part is specified. The execution device is
The primary information is information indicating that the integral term is within the normal range and the voltage value or the current value is higher than the normal range.
When the secondary information is information indicating that the fuel pressure, the integral term, and the rotation speed are within the normal range, and the voltage value and the current value are higher than the normal range.
The control device for a fuel supply system according to claim 1 or 2, wherein in the determination process, it is determined that a malfunction of the impeller has occurred. The execution device is
The primary information is information indicating that the fuel pressure is lower than the normal range, the voltage value, the current value, and the rotation speed are within the normal range, and the integral term is higher than the normal range.
When the secondary information is information indicating that the fuel pressure is within the normal range and the integral term, the voltage value, the current value, and the rotation speed are higher than the normal range.
The control device for a fuel supply system according to any one of claims 1 to 3, wherein in the determination process, it is determined that the suction filter in the fuel pump is clogged. The execution device is
The primary information is information indicating that the fuel pressure, the voltage value, the current value, and the rotation speed are lower than the normal range and the integration term is within the normal range.
When the secondary information is information indicating that the fuel pressure, the voltage value, the current value, and the rotation speed are lower than the normal range and the integral term is higher than the normal range.
The control device for a fuel supply system according to any one of claims 1 to 4, wherein in the determination process, it is determined that an abnormality has occurred in the pump control device. The execution device is
The primary information is information indicating that the fuel pressure is lower than the normal range, the voltage value, the current value, and the rotation speed are within the normal range, and the integral term is higher than the normal range.
When the secondary information is information indicating that the fuel pressure is lower than the normal range and the integral term, the voltage value, the current value, and the rotation speed are higher than the normal range.
The control device for a fuel supply system according to any one of claims 1 to 5, wherein in the determination process, it is determined that an abnormality has occurred in the pressure sensor. The execution device is
The primary information is information indicating that the integral term is lower than the normal range, the voltage value, the current value, and the rotation speed are within the normal range, and the fuel pressure is higher than the normal range.
When the secondary information is information indicating that the integral term, the voltage value, the current value, and the rotation speed are lower than the normal range and the fuel pressure is higher than the normal range.
The control device for a fuel supply system according to any one of claims 1 to 6, wherein in the determination process, it is determined that an abnormality has occurred in the pressure sensor. The execution device is
The primary information is information indicating that the fuel pressure is lower than the normal range, the integral term is within the normal range, and the voltage value, the current value, and the rotation speed are "0".
When the secondary information is information indicating that the fuel pressure is lower than the normal range, the integral term is higher than the normal range, and the voltage value, the current value, and the rotation speed are "0". ,
The control device for a fuel supply system according to any one of claims 1 to 7, wherein in the determination process, it is determined that the input of the required rotation speed to the pump control device is interrupted. The execution device is
The primary information is information indicating that the fuel pressure, the voltage value, and the current value are lower than the normal range, and the integral term and the rotation speed are within the normal range.
When the secondary information is information indicating that the fuel pressure is lower than the normal range and the integral term and the rotation speed are higher than the normal range.
The control device for a fuel supply system according to any one of claims 1 to 8, which determines that a fuel shortage has occurred in the determination process.

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