JP5906641B2 - Vehicle drive control device - Google Patents

Description

  The present invention relates to a vehicle drive control device, and more particularly, to a vehicle drive control device that can prevent unstable behavior of a vehicle that can run while the internal combustion engine is stopped and that is caused by poor start of the internal combustion engine.

Vehicles that are equipped with an internal combustion engine and a drive motor and can run with at least the internal combustion engine stopped include a range / extender electric vehicle and a plug-in hybrid vehicle (PHEV). These vehicle drive control devices include drive control means for controlling the internal combustion engine and the drive motor, and an SOC (State Of Charge) which is a power storage state of the drive battery during traveling while the internal combustion engine is stopped. When it becomes low, it controls to start the internal combustion engine.
Japanese Unexamined Patent Application Publication No. 2011-121482 discloses a technique for changing the vehicle speed that triggers the start according to the stop time of the internal combustion engine.
Japanese Patent No. 3214 1 50 discloses, in drivable parallel type hybrid vehicle by the driving force of the driving motor alone, techniques for operating an internal combustion engine is disclosed utilizing a braking force to prevent the startability deterioration of the internal combustion engine ing.
Japanese Patent Application Laid-Open No. 2010-174840 discloses a technique for changing the start frequency of the internal combustion engine by adjusting the start SOC threshold value of the internal combustion engine in accordance with the required purge amount of the canister.
Japanese Patent Application Laid-Open No. 2010-158927 discloses a technique for operating and purging the evaporated fuel gas collected in the canister during a stoppage while operating the internal combustion engine with minimal deterioration in fuel efficiency regardless of the remaining battery level of the plug-in hybrid vehicle. Yes.

JP 2011-121482 A Japanese Patent No. 3214150 JP 2010-174840 A JP 2010-158927 A

By the way, in the range / extender type electric vehicle and the plug-in hybrid vehicle, there are situations (situations) in which the internal combustion engine is not used for a long period of time depending on the usage method of the vehicle user (user, driver). A conventional vehicle that runs with the driving force of the internal combustion engine will not start the internal combustion engine if left untreated for a long time, but the situation for starting the internal combustion engine next time is greatly different from that of a range extender type electric vehicle.
The latter (automobile running with the driving force of the internal combustion engine) starts the internal combustion engine when the vehicle is stopped, while the former (range extender type electric automobile or the like) may start the internal combustion engine while running. If a start-up failure occurs when starting the internal combustion engine during driving, the range / extender type electric vehicle or plug-in hybrid vehicle will have reduced output (driving force) during driving, which has the disadvantage of affecting smooth driving. is there.

In general, it is considered that an internal combustion engine has a high possibility of starting failure in the following situations.
・ When the internal combustion engine has not been started for a long period of time ・ In a low-temperature environment ・ When the oil has not been changed for a long time Even if some conditions overlap, there is no problem in most situations, I would like to avoid starting the internal combustion engine in a situation as much as possible, and I would like to start it when approaching such a situation.

  The present invention reduces the opportunity to start an internal combustion engine in a situation that causes an undesirable start failure, and ensures a long non-use time during which the internal combustion engine is stopped while starting within a problem-free range. Objective.

The present invention includes a drive control unit that includes an internal combustion engine and a drive motor, and that controls the internal combustion engine and the drive motor, and at least the vehicle drive control device that can travel with the internal combustion engine stopped. The internal combustion engine has a function of starting the internal combustion engine by outputting a start command when a predetermined start condition is satisfied, and obtaining a first function corresponding to a possibility of occurrence of a start failure of the internal combustion engine. A second function corresponding to the impact due to the starting failure is calculated, a starting factor value corresponding to the starting failure risk of the internal combustion engine is calculated based on the first function and the second function, and this starting factor value The internal combustion engine is forcibly started when is equal to or greater than a preset value .

In the present invention, the forced start is performed in consideration of the risk of start failure by the two functions of the function corresponding to the possibility of start failure and the function corresponding to the impact due to start failure. Undesirable levels of some starting failures can be reduced.
Since the present invention forcibly starts by judging the risk of starting failure, it is possible to secure a certain amount of non-use time of the internal combustion engine.

FIG. 1 is a system diagram of a vehicle drive control device. (Example) FIG. 2 is a flowchart of the vehicle drive control apparatus. (Example) FIG. 3 is a table showing a setting example of the first function. (Example) FIG. 4 is a graph showing a setting example of the first function. (Example) FIG. 5 is a table showing a setting example of the second function. (Example) FIG. 6 is a graph showing a setting example of the second function. (Example) FIG. 7 is a graph showing a setting example of a setting value for determining the starting factor value. (Example)

  Embodiments of the present invention will be described below with reference to the drawings.

1 to 7 show an embodiment of the present invention. In FIG. 1, 1 is a vehicle and 2 is a drive control device. The vehicle 1 is a range extender type electric vehicle that can run with at least the internal combustion engine 3 stopped. In the drive control device 2 of the vehicle 1, a generator 4 driven by an internal combustion engine 3, a drive battery 5, and a drive motor 6 are connected by a high voltage cable (HV + / HV−) 7. Although not shown, the internal combustion engine 3 includes a control device that performs fuel injection control and air-fuel ratio control, and various devices that are generally known detection means and auxiliary devices provided on the input and output sides thereof. An electric load 8 and a charger 9 are connected to the high voltage cable 7. The other electric load 8 is an electric load driven by a high voltage such as an A / C compressor or an air conditioning heater. The charger 9 is connected to the external charger 10 to charge the driving battery 5.
The driving battery 5 can store the electric power generated by the generator 4 and the external electric power supplied by the charger 9, and can output SOC (State Of Charge) which is a power saving state. The drive motor 6 is driven using the power generated by the generator 4 or the power stored in the drive battery 5, and can drive the vehicle 1 by driving the drive wheels 12 via the drive shaft 11. It is. Thus, the vehicle 1 is equipped with the internal combustion engine 3 and the drive motor 6, and can travel with the drive motor 6 while at least the internal combustion engine 3 is stopped.
The internal combustion engine 3, the generator 4, the drive battery 5, and the drive motor 6 are connected to drive control means 13 of the drive control device 2. An accelerator sensor 14 that detects the accelerator opening and a vehicle speed sensor 15 that detects the vehicle speed are connected to the drive control means 13. The drive control means 13 inputs internal combustion engine speed information from the internal combustion engine 3, inputs power saving state information (SOC) from the drive battery 5, inputs an accelerator opening signal from the accelerator sensor 14, and a vehicle speed sensor 15. Input the vehicle speed signal from.
The drive control means 13 is an internal combustion engine control command for driving / stopping the internal combustion engine 3, a power generation torque command to the generator 4 connected to the internal combustion engine 3, management of the SOC of the high-voltage drive battery 5, the vehicle 1 A drive torque command to the drive motor 6 for propelling the vehicle is performed, and the system mounted on the vehicle 1 is integratedly controlled.

The drive control device 2 of the vehicle 1 manages the SOC of the drive battery 5 by the drive control means 13 and starts the internal combustion engine 3 when the SOC falls below a certain threshold value. If the vehicle user frequently charges the drive battery 5 with the external charger 10, there is a situation in which the SOC of the drive battery 5 is kept relatively high and the internal combustion engine 3 is not started for a long period of time. . If there is a situation in which the internal combustion engine 3 is not started for a long time as described above, a start failure may occur at the next start.
Generally, it is considered that the internal combustion engine 3 is likely to cause a start failure in the following situation.
-When the internal combustion engine has not been started for a long period of time-In a low temperature environment-When the oil has not been changed for a long period of time A poor starting of the internal combustion engine 3 causes an impact. The impact caused by the start failure of the internal combustion engine 3 is a physical impact applied to the vehicle 1 or an energy loss corresponding thereto. The following situations have a large impact due to poor starting of the internal combustion engine 3.
-When traveling at high speed (the output of the drive motor 6 is suddenly reduced due to the SOC of the drive battery 5 being too low)
・ Low temperature environment (decrease in passenger compartment temperature due to inability to secure heating power)
・ High temperature environment (rise in passenger compartment temperature due to inability to secure power for cooling)
Before this situation occurs, it is necessary to inform the vehicle user of the possibility of the start failure of the internal combustion engine 3. Further, it is necessary to prevent the starting failure of the internal combustion engine 3 itself.

From the above viewpoint, the drive control device 2 of the vehicle 1 not only reduces the SOC of the drive battery 5, but also the possibility of the start failure of the internal combustion engine 3 and the impact due to the start failure are large. Is forcibly started, and the vehicle user is notified of the possibility of starting failure.
The drive control device 2 includes, in the drive control means 13, an outside air temperature sensor 16 that detects the outside air temperature of the vehicle 1, a time measuring means 17 that times the unused time of the internal combustion engine 3, and a notification means that notifies the vehicle user of a message. 18 is connected. The drive control means 13 inputs an outside air temperature signal from the outside air temperature sensor 16, inputs non-use time information of the internal combustion engine 3 from the time measuring means 17, and a vehicle user can cause a start failure of the internal combustion engine 3 to the notification means 18. Output a message to notify about sex.
The drive control means 13 has a function of starting the internal combustion engine 3 by outputting a start command when a predetermined start condition is satisfied. When the start factor value P is less than the preset set value A, that is, in normal use, the drive control means 13 is based on the detected decrease in the SOC of the drive battery 5 as a predetermined start condition. The internal combustion engine 3 is started in order to keep the SOC of the drive battery 5 within a predetermined range. The drive control means 13 generates power by the generator 4 by starting the internal combustion engine 3 and charges the drive battery 5. A part of the generated power can be distributed so as to be used for driving the vehicle 1.
On the other hand, the drive control means 13 obtains a first function corresponding to the possibility of the start failure of the internal combustion engine 3, obtains a second function corresponding to the impact due to the start failure of the internal combustion engine 3, and the first function. Based on the second function, a starting factor value corresponding to the risk of starting failure of the internal combustion engine 3 is calculated, and the internal combustion engine 3 is forcibly started based on the determination on the starting factor value.
In the embodiment, the drive control means 13 uses a numerical value X = f (t, t, which corresponds to the possibility of start failure of the internal combustion engine 3 based on the non-use time t and the outside air temperature T of the internal combustion engine 3 as a first function. T) is set, and the second function Y sets a numerical value Y = g (v, T) corresponding to the impact due to the start failure of the internal combustion engine 3 based on the vehicle speed v and the outside air temperature T, and sets the start factor value P to When the numerical value X of the first function is multiplied by the numerical value Y of the second function (P = X * Y), and this starting factor value P is equal to or greater than a preset set value A (P ≧ In A), the internal combustion engine 3 is forcibly started.
Further, the drive control means 13 has a function of detecting the SOC of the drive battery 5, and when the start factor value P is less than a preset set value A (P <A), a predetermined start condition The internal combustion engine 3 is started to keep the SOC of the driving battery 5 within a predetermined range based on the detected SOC of the driving battery 5.

Here, the value X of the possibility of starting failure, the impact value Y due to the starting failure, and the set value A will be described.
That is, the value of the possibility of start failure is X (0 ≦ X ≦ 1), the impact value due to start failure is Y (0 ≦ Y ≦ 1), and these are multiplied to determine the start factor of the internal combustion engine 3. The value is P (0 ≦ P ≦ 1).
P = X * Y (1)
Using this P, the internal combustion engine 3 is forcibly started when the following relationship is established.
P ≧ A (2)

The set value A is a constant. Further, the value X of the possibility of starting failure is a function of the non-use time t and the outside air temperature T of the internal combustion engine 3. The impact value Y due to the start failure is a function of the vehicle speed v and the outside temperature T.
X = f (t, T) (3)
Y = g (v, T) (4)

An example of setting the value X by the first function is shown in FIGS. It is recommended that the value X of the first function be set such that the value becomes larger as the non-use time t of the internal combustion engine 3 becomes longer and the outside air temperature T becomes lower.
Next, examples of setting the value Y by the second function are shown in FIGS. It is recommended that the value Y of the second function be set such that the value increases as the vehicle speed v increases and the outside air temperature T decreases.
However, Y = 0 should not be set when the vehicle speed v = 0. This is because when the value X of the first function is very large, the internal combustion engine 3 is actively started even at v = 0 (if the abnormality of the internal combustion engine 3 is known before starting running, damage to the vehicle user). Is minimized). Here, as an example, the starting factor value P (= X * Y) at the outside air temperature T = 25 ° C. is shown in FIG. When the set value A = 0.18, the internal combustion engine 3 is forcibly started in a region where the starting factor value P is above the plane S.
In addition, since sensing is difficult, the element of oil change is not included intentionally, but if possible, it is desirable to include it as an element of the value X of the first function (oil change days, oil properties, etc.)

The drive control device 2 of the vehicle 1 starts the internal combustion engine 3 when a predetermined start condition is satisfied, while starting the internal combustion engine 3 based on the value X of the first function and the value Y of the second function. A starting factor value P corresponding to the defect risk is calculated, and the internal combustion engine 3 is forcibly started based on the determination with respect to the starting factor value P.
As shown in FIG. 2, when the control is started (101), the drive control device 2 of the vehicle 1 inputs various parameters (non-use time t, outside air temperature T, vehicle speed v) (102), and the first function The value X of the second function is obtained (103), the value Y of the second function is obtained (104), the starting factor value P is obtained from the value X of the first function and the value Y of the second function (105), and the starting factor is obtained. It is determined whether the value P is equal to or greater than a set value A (0 ≦ A ≦ 1) (106).
If this determination (106) is YES, the internal combustion engine 3 is forcibly started (107), and the control is ended (108). If this determination (106) is NO, the internal combustion engine 3 is normally started (starting at an arbitrary timing such as when the start condition is established by the SOC of the driving battery 5) (109), and the control is ended ( 108).

Thus, the drive control device 2 of the vehicle 1 is based on the first function corresponding to the possibility of the start failure of the internal combustion engine 3 and the second function corresponding to the impact due to the start failure of the internal combustion engine 3. A starting factor value corresponding to the risk of starting failure of the internal combustion engine 3 is calculated, and the internal combustion engine 3 is forcibly started based on the determination with respect to the starting factor value.
As a result, the drive control device 2 performs the forced start in consideration of the risk of a start failure by using two functions, so that it is possible to reduce some of the start failures that are not desired among the start failures. In addition, since the drive control device 2 determines the risk of starting failure and forcibly starts, the non-use time of the internal combustion engine 3 can be secured to some extent.
Further, the drive control device 2 sets a numerical value X corresponding to the possibility of a start failure of the internal combustion engine 3 based on the non-use time t and the outside air temperature T of the internal combustion engine 3 as the first function, Based on the vehicle speed v and the outside air temperature T, the function sets a numerical value Y corresponding to the impact caused by the starting failure of the internal combustion engine 3, and multiplies the numerical value X of the first function and the numerical value Y of the second function to start the factor. The value P is calculated, and the internal combustion engine 3 is forcibly started when the starting factor value P is greater than or equal to the preset set value A.
As a result, the drive control device 2 determines not only the vehicle speed indicating the traveling state of the vehicle 1 but also the outside air temperature T related to the state of the internal combustion engine 3 and the non-use time t. High and low judgment can be made with high accuracy. In addition, since the drive control device 2 can set the determination of the start failure risk as desired, it is possible to set the optimal forced start timing while ensuring the non-use time according to the unique characteristics of each internal combustion engine for each vehicle.
Since the set value A is set to an acceptable level, the judgment is “If the start factor value P is greater than or equal to the set value A”, the actual value is less than the set value A in normal vehicle usage. Yes, it will be forcibly started at the boundary from less than the set value A to the set value A, and there will be no situation of starting for the first time in an undesired situation completely exceeding the set value A. it can.
Further, when the starting factor value P is less than the preset set value A (P <A), the drive control device 2 determines this based on the SOC of the driving battery 5 detected as a predetermined starting condition. The internal combustion engine 3 is started to keep the SOC of the drive battery 5 within a predetermined range.
Thus, the drive control device 2 starts at any time according to the SOC of the drive battery 5 in normal use with a relatively low risk of starting failure, and thus starts according to the use state of the vehicle user. In addition to this, the drive control device 2 can forcibly start the internal combustion engine 3 to maintain a low start failure risk while securing a non-use time of the internal combustion engine 3.
In this embodiment, the starting factor value P is obtained by multiplication (multiplication) of the value X of the first function and the value Y of the second function. However, depending on the specifications and characteristics of the internal combustion engine 3, It can be considered that the starting factor value P can be obtained by adding (adding) the value X of the first function and the value Y of the second function.
In this embodiment, the application method for the range extender type electric vehicle has been described. However, the present invention can also be applied to a torque split type electric vehicle (HEV) and a parallel type hybrid vehicle (HEV) that can hardly cut an internal combustion engine. is there.

Further, the drive control device 2 of the vehicle 1 notifies the vehicle user of the possibility of the start failure of the internal combustion engine 3. This notification is performed when the vehicle user is away from the vehicle 1 or when the vehicle user gets on the vehicle 1. This is to prevent anxiety given to the vehicle user when the internal combustion engine 3 is started by the above-described control. For example, a situation where the vehicle 1 is left in the garage for a long time and then charged, and the vehicle 1 is started up with the recognition that the internal combustion engine 3 does not start. As a result, the internal combustion engine 3 is operated in the garage. .
Therefore, when the numerical value X of the first function corresponding to the possibility of starting failure of the internal combustion engine 3 exceeds preset values B and C, the drive control means 13 notifies the vehicle user by the notification means 18. Message is output.
First, a vehicle user who is away from the vehicle 1 uses an external charger 10 that gives notification by a communication means capable of wireless communication such as a mobile phone or a communication means capable of wired communication such as PLC communication using a charging cable. . By this communication means, the vehicle user can constantly confirm information such as the next oil change period and the non-use time of the internal combustion engine 3, and the value X of the first function corresponding to the possibility of the start failure of the internal combustion engine 3 When a certain set value B (0 ≦ B ≦ 1) is exceeded, a caution is notified to the vehicle user.
Next, a vehicle user who has boarded the vehicle 1 is notified by notification means (display, voice, etc.) via the interface of the vehicle 1. This notifying means notifies the vehicle user of an alarm when the possibility of starting failure X exceeds a set value C (0 ≦ C ≦ 1) (notifies the vehicle speed or the like for starting the internal combustion engine 3). You may).

For this reason, as shown in FIG. 1, the notification means 18 communicates a message output with a communication signal in order to indirectly notify the vehicle user via a device outside the vehicle (external charger 10, wireless communication station). The first notification function unit 181 is configured by output, and the second notification function unit 182 performs message output by sound output or display output in order to directly notify the vehicle user.
The first notification function means 181 includes a transmission / reception device 19 that outputs a signal to the outside of the vehicle by wire or wirelessly. The first notification function means 181 outputs a message to the vehicle user as a communication signal output when the numerical value X of the first function corresponding to the possibility of starting failure exceeds a preset value B. The message is output as an acoustic output or a display output to a portable terminal or the like possessed by the vehicle user via the transmission / reception device 20 of the external charger 10 outside the vehicle or a wireless communication station.
Said 2nd notification function means 182 is provided with the apparatus 21 mounted in the vehicle inside by the wire communication. When the numerical value X of the first function corresponding to the possibility of starting failure exceeds a preset setting value C, the second notification function means 182 outputs a message to the vehicle user from the device 21 by sound output or display output. Output.

As described above, the drive control device 2 of the vehicle 1 has a case in which the numerical value X of the first function corresponding to the possibility of the start failure of the internal combustion engine 3 exceeds the preset values B and C (X> B, In X> C), the notification means 18 outputs a message to the vehicle user.
Thereby, since the drive control apparatus 2 can notify in advance of the occurrence of an undesirable starting failure, it can suppress discomfort given to the vehicle user. Further, the drive control device 2 can prompt the vehicle user to perform maintenance, and can improve the durability of the vehicle 1.
Since the setting value B and the setting value C of the notification means 18 are settings for the value X of the first function, they cannot be generally compared, but while the starting factor value P <the setting value A, the first function Setting each setting value A, B, C so that the value X> the setting value B and the value X of the first function> the setting value C will notify an undesired start failure. desirable.
The drive control device 2 has notified the vehicle user of the possibility of occurrence of a start failure of the internal combustion engine 3 to the vehicle user by the notification means 18. However, an operation element such as a start switch that can arbitrarily start the internal combustion engine 3 is provided. When the vehicle user is informed of the starting factor value P of the internal combustion engine 3 or information related thereto by the notification means 18, the vehicle user forcibly starts the internal combustion engine 3 by operating the operating element himself / herself. You can also

  The present invention is capable of preventing unstable behavior due to poor starting of an internal combustion engine of a vehicle capable of stopping the internal combustion engine during traveling, and is applied to a system equipped with a generator such as a power source for a train car and a bus. Can be applied.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Drive control apparatus 3 Internal combustion engine 4 Generator 5 Drive battery 6 Drive motor 7 High voltage cable 8 Other electric load 9 Charger 10 External charger 11 Drive shaft 12 Drive wheel 13 Drive control means 14 Acceleration sensor 15 Vehicle speed sensor 16 Outside temperature sensor 17 Timekeeping means 18 Notification means

Claims (4)

In a drive control device for a vehicle that is equipped with an internal combustion engine and a drive motor, and that has drive control means for controlling the internal combustion engine and the drive motor, and that can run at least while the internal combustion engine is stopped, the drive control means has a predetermined start While having a function of starting the internal combustion engine by outputting a start command when the condition is satisfied, a first function corresponding to the possibility of occurrence of the start failure of the internal combustion engine is obtained, and due to the start failure of the internal combustion engine A second function corresponding to impact is obtained, a starting factor value corresponding to the risk of starting failure of the internal combustion engine is calculated based on the first function and the second function, and this starting factor value is set in advance. A vehicle drive control device , wherein the internal combustion engine is forcibly started when the value is equal to or greater than a value . The drive control means sets the numerical value corresponding to the possibility of the start failure of the internal combustion engine based on the non-use time and the outside air temperature of the internal combustion engine as the first function, and the second function as a vehicle speed. And a numerical value corresponding to the impact due to the starting failure of the internal combustion engine based on the outside air temperature, and the starting factor value is calculated by multiplying the numerical value of the first function and the numerical value of the second function. 2. The vehicle drive control device according to claim 1, wherein the internal combustion engine is forcibly started when the starting factor value is equal to or greater than a preset set value. The vehicle is equipped with a drive battery, and the drive control means has a function of detecting the SOC of the drive battery, and the predetermined factor is determined when the start factor value is less than a preset value. 3. The vehicle drive according to claim 2, wherein the internal combustion engine is started in order to keep the SOC of the driving battery within a predetermined range based on the SOC of the driving battery detected as a starting condition of the vehicle. Control device.   The drive control means includes notification means for notifying a vehicle user, and when the numerical value of the first function corresponding to the possibility of occurrence of a start failure of the internal combustion engine exceeds a preset value, the notification means The vehicle drive control device according to claim 2, wherein a message is output to the vehicle user by the above.

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