JP2010241185A - Charging controller for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control charging regeneration during the deceleration fuel cut of a hybrid vehicle so as to be capable of improving the fuel consumption more efficiently. <P>SOLUTION: When validity/invalidity of charging during deceleration fuel cut is to be determined, and when fuel cut is started, the fuel quantity conversion value of electrical energy to be obtained, by performing charging and fuel consumption relatively increasing due to the fact that a fuel cut period becomes short by performing charging are predictively calculating and comparing; then if the former is larger than the latter, regenerative charging is performed; and otherwise, the regenerative charging is not performed. Consequently, it is possible to effectively improve fuel consumption, by preliminarily determining the case that fuel consumption improvement is expected and by performing charging, in charging control, when deceleration fuel cut is to be performed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to regenerative charging control of a hybrid vehicle.

  In recent years, low fuel consumption vehicles have been actively developed from the viewpoints of energy problems and environmental protection, and among them, hybrid vehicles that have an engine and a motor and can use both for driving are attracting attention. The hybrid vehicle assists engine operation by accelerating and driving the motor in a low load and low rotation range where the engine efficiency is poor, while using the motor as a generator for steady running and deceleration. By charging the battery with surplus energy, fuel efficiency is improved.

  Since the motor is rotated as a generator during charging, the load on the vehicle propulsion force increases. Therefore, in order to improve fuel efficiency effectively, it is necessary to charge at a suitable timing.

  Patent Document 1 proposes an engine output control method that can be most efficiently charged with respect to fuel consumption when charging a battery while running with the engine as a power source.

  Patent Document 2 proposes a motor control method for calculating regenerative power from information related to vehicle speed and the remaining battery capacity, and preventing overcharging of the battery based on the regenerative power, with regard to regenerative charging during deceleration. Has been.

JP-A-9-98516 JP-A-7-123509

  An object of the present invention is to optimize the regenerative charge control at the time of deceleration fuel cut from the viewpoint of both the regenerative charge amount and the fuel consumption amount.

  In the present invention, when determining whether or not regeneration at the time of deceleration fuel cut is possible, at the start of fuel cut, the fuel amount converted value of the electric energy obtained by performing regeneration and the fuel cut period is shortened by performing regeneration. Therefore, the fuel consumption that increases relatively is calculated and compared, and regenerative charging is performed only when the former is determined to be greater than the latter.

  According to the present invention, in the charging control at the time of deceleration fuel cut, the fuel consumption can be effectively improved by performing the charging by predicting and judging in advance the case where an improvement in the fuel consumption can be expected.

The hardware block diagram of the hybrid vehicle charge control apparatus in a 1st Example. The figure showing the relationship between the presence or absence of regeneration at the time of a fuel cut, and the length of a fuel cut period. The figure which shows the flow of the whole control in a 1st Example. The figure which shows the prediction calculation method of the fuel quantity X in a 1st Example. The figure which shows the calculation method of fuel cut period ta and tb in a 1st Example. The figure which shows the main parameters in a vehicle physical model. The figure showing the fuel injection quantity characteristic with respect to engine speed and engine torque. The figure which shows the prediction calculation method of the electric energy Y which can be acquired in a 1st Example. The figure showing the fuel consumption characteristic and output characteristic with respect to engine speed and engine torque. The figure showing the shift of the engine operating point on a fuel injection amount characteristic diagram. The figure showing the difference in the vehicle speed change by the presence or absence of regeneration at the time of a fuel cut. The hardware block diagram of the charge control apparatus of the vehicle mounted with ISG in a 2nd Example. The figure showing the presence or absence of regeneration and an idle stop at the time of a fuel cut, and the relationship between the length of a fuel cut period. The figure which shows the flow of the whole control in a 2nd Example. The figure which shows the prediction calculation method of the fuel quantity xa in the 2nd Example, xb. The figure which shows the fuel cut period tc calculation method in 2nd Example.

  An embodiment of the hybrid vehicle regenerative charge control technology of the present invention will be described below.

  As a first embodiment of the present invention, an application example to a so-called mild hybrid vehicle will be described. In the mild hybrid vehicle of the present embodiment, it is assumed that the engine can run and the engine + motor with motor assist can be run.

  FIG. 1 shows the hardware configuration of the hybrid vehicle charge control device of this embodiment. This hybrid vehicle has an engine 101 and a motor generator 102 as drive sources, and can be driven by both the engine and the motor generator 102 in addition to being driven only by the engine 101. The motor generator 102 can contribute to driving by engaging the clutch based on a command from the ECU 106, and receives a rotational force from the outside by a part of torque from the driving wheel depending on the situation. Functions as a generator. Torque generated by the engine 101 and the motor generator 102 is shifted by the CVT 107 based on a command from the ECU 106, increased by the final reduction gear 108, and then transmitted to the drive wheels 109. The motor generator 102 is supplied with power from the battery 103 through the power control unit 104 and used for driving, and also has a function as a generator by being rotated from the outside. The generated power is generated by the power control unit 104. The voltage is adjusted to an appropriate voltage and the battery 103 is charged. The motor generator 102 as a generator uses a part of the torque of the engine 101 or receives a rotational force by a part of the torque from the driving wheel 109 during deceleration, and charges the battery 103 with the generated electric power. The power control unit 104 can switch between the charging operation and the power running operation of the motor generator 102 based on a command from the ECU 106. Engine 101 and motor generator 102 are controlled based on a command from ECU 106. However, motor generator 102 receives a command from ECU 106 through power control unit 104. The ECU 106 detects the engine speed from the engine speed detection device 110, the operating state of the motor generator 102 from the power control unit 104, the current SOC and temperature of the battery from the battery 103, and the accelerator opening from the accelerator opening detection device 111. The vehicle speed is obtained from the vehicle speed detection device 112, the road information such as the road surface gradient and the legal speed is obtained from the car navigation system 113, and the information by the road-to-vehicle communication 114 is obtained.

  Next, the relationship between the presence or absence of regeneration and the energy balance trade-off due to the length of the fuel cut period during fuel cut during deceleration will be described with reference to FIG. Generally, when a predetermined fuel cut permission condition is established for the accelerator opening obtained from the accelerator opening detecting device 111 and the engine rotational speed obtained from the engine rotational speed detecting device 110, the fuel cut is performed (t1). ). In FIG. 2, the fuel cut flag is changed from 0 to 1 to indicate the start of fuel cut. The state from the normal fuel cut to the fuel cut recovery is shown in FIG. Since no driving force is generated from the engine 101 during the fuel cut, the engine speed decreases with the vehicle speed, and when the engine speed reaches the fuel cut recovery speed (t3), the fuel supply is resumed (fuel cut flag 1 → 0). The fuel cut recovery engine speed is set to a predetermined number of engine speeds higher than the idle engine speed so as not to cause engine stall.

  When regenerative charging is performed during the fuel cut period during deceleration ((ii) in FIG. 2), in addition to running resistance, a load for generating power by rotating the motor generator 102 is generated, and regenerative charging is not performed. Compared with the case (i), the engine speed decreases more quickly. That is, since the fuel supply speed is reached early and the fuel supply is resumed (t2), the amount of fuel to be used increases compared to the case where regenerative charging is not performed. In (ii), the vehicle speed decreases rapidly for the same reason, and therefore the distance that can travel from t1 to t3 is shorter than (i). In order to travel the same distance as (i), energy may be additionally consumed depending on the vehicle speed after t3. Therefore, when (i) and (ii) are compared, there is a trade-off relationship between the amount of energy newly obtained by regenerative charging and the amount of consumed energy that increases.

  Hereinafter, regenerative charge control in consideration of the trade-off relationship will be described. The overall flow of this control is shown in FIG.

  In step 201, it is determined whether or not a predetermined fuel cut permission condition is satisfied for the engine speed obtained from the engine speed detecting means 110 and the accelerator opening obtained from the accelerator opening detecting device 111. If the cutting permission condition is satisfied, the fuel is cut (step 202), and if not satisfied, the fuel supply is continued (step 203).

  When the fuel cut is performed, in step 204, when the regenerative charge is performed during the fuel cut period, an extra required fuel consumption X (see FIG. 2) is compared with the case where the regenerative charge is not performed. Predict and calculate. A method for calculating the fuel consumption amount X will be described later.

  Next, in step 205, the amount of electric power Y (see FIG. 2) that can be newly acquired when regenerative charging is performed during the fuel cut period is predicted and calculated. A method for predicting the obtainable power amount Y will be described later.

  Next, in step 206, the acquirable electric energy Y predicted and calculated in step 205 is converted into a corresponding fuel consumption Yf (see FIG. 2). The conversion method from Y to Yf will be described later.

  Next, at step 207, when the regenerative charge is performed during the fuel cut period, an additional travel fuel amount Z necessary for traveling the same distance as when the regenerative charge is not performed is predicted and calculated. A method for predicting the additional travel fuel amount Z will be described later.

  In step 208, the sum of the fuel consumption amount X obtained in step 204 and the additional travel fuel amount Z obtained in step 207 is compared with the fuel consumption amount Yf obtained in step 206. Here, if Yf is greater than (X + Z), it can be determined that there is a merit of performing regenerative charging during the fuel cut period, and therefore, regeneration is performed in step 209. In other cases, regeneration is not performed because it is considered that there is no merit of regenerative charging.

  As described above, with respect to the charge control at the time of deceleration fuel cut, it is possible to effectively improve the fuel efficiency by predicting and judging in advance the case where an improvement in fuel efficiency can be expected.

  Next, the predictive calculation method of the fuel amount X in step 204 of FIG. 3 will be described with reference to FIG.

In the prediction calculation of the fuel amount X, the fuel injection amount Fidl required for maintaining the idle speed, the fuel cut period without regeneration (referred to as ta), the fuel cut period with regeneration (referred to as tb), (301, 302, 303), and using these,
X = Fidl * (ta−tb) (1)
Thus, the fuel amount X is obtained (304). A method for obtaining ta, tb, and Fidl will be described with reference to FIGS.

  FIG. 5 is a diagram showing a calculation method for obtaining the fuel cut periods ta and tb. Information on the engine speed, vehicle speed, and gradient at the start of fuel cut is obtained from the respective detection means (110, 112, 113), and a decrease prediction of the engine speed is made in the vehicle physical model 402 to cut the fuel. A period is calculated. The calculation in the vehicle physical model 402 will be described later. At this time, by assuming the presence / absence of regeneration by the regeneration presence / absence assumption means 401, the fuel cut period ta when there is no regeneration and the fuel cut period tb when there is regeneration are respectively obtained. When there is no regeneration, the clutch 105 is disengaged, so there is no load for rotating the motor generator 102, the vehicle speed decreases due to engine drive resistance and travel resistance (air resistance, rolling resistance, uphill resistance), and the engine speed Decreases. When regeneration is present, the clutch 105 is engaged, and the motor generator 102 and the engine 101 rotate at the same rotational speed. Therefore, in addition to the above running resistance, a load for rotating motor generator 102 and a load accompanying power generation are added as factors for decreasing the engine speed, and the engine speed is reduced earlier than when there is no regeneration. Therefore, there is a relationship ta> tb.

  Hereinafter, an outline of calculation for the vehicle physical model 402 for predicting the engine speed will be described. The main parameters are shown in FIG. The meanings of the symbols used in the calculation formula are as follows.

F: Vehicle driving force
Fe: Driving force by the engine
Fm: Driving force or charging load by motor generator
Fr: Resistance force that prevents the vehicle from traveling forward
Te: Engine torque Tcom: Engine combustion pressure torque Tfric: Friction loss torque in the engine
Tm: Motor generator torque Tmot: Torque during motor generator powering Tgen: Load torque during motor generator charging
Rr: Rolling resistance
Rl: Air resistance
Rs: resistance to climb
M: Vehicle weight
V: Vehicle speed
V0: Initial vehicle speed
α: Vehicle acceleration
r: tire radius
Nd: Drive shaft rotation speed
Ne: Engine speed
i: The total reduction ratio vehicle motion is the equation of motion,
F = M * α (2)
Follow. The left side of equation (2), vehicle driving force F is
F = Fe + Fm−Fr (3)
Each driving force or resistance force is represented by
Fe = Te * i / r (4)
Fm = Tm * i / r (5)
Fr = Rr + Rl + Rs (6)
It is. Engine torque Te and motor generator torque Tm are
Te = Tcomb−Tfric (7)
Tm = Tmot−Tgen (8)
It can be expressed as Either Tmot or Tgen has a value depending on the operating state (powering / charging) of the motor generator. Further, the vehicle acceleration α on the right side of the equation (2) is the vehicle speed V,
V = ∫αdt (9)
Are in a relationship. By applying the equations (3) to (9) to the equation (2) and giving the initial value V0 of the vehicle speed, a calculation formula for the vehicle speed can be obtained.

V = V0 + (1 / M) ∫Fdt (10)
Conversion from vehicle speed to drive shaft speed is
Nd = V / (2πr) (11)
And the engine speed is
Ne = Nd * i (12)
Is required.

  At the time of fuel cut which is the subject of the present invention, Tcomb = 0 on the right side of the equation (7).

In the equation (8), Tm = −Tgen when performing regenerative charging, and Tm = 0 when not performing regenerative charging. Therefore, the vehicle driving force in each of (i) and (ii) is
(I) Fi = −Tfric * i / r−Fr (13)
(Ii) Fii = − (Tfric + Tgen) * i / r−Fr (14)
The calculation calculation of the engine speed reduction is performed by integrating the expressions (10) to (12) using the expressions (13) and (14). This is the end of the description of the vehicle physical model 402.

  The fuel injection amount Fidl required for maintaining the idling engine speed is predicted by selecting an engine operating point (engine speed, engine torque) corresponding to the running state using a fuel injection characteristic chart as shown in FIG. Can do. For example, the engine operating point when an uphill is detected by the car navigation system 113 is a point that requires a larger torque than when running on a flat road, and the fuel injection amount Fidl is considered to be increased. For the fuel injection amount Fidl, a predetermined fixed value can be used without using the map as shown in FIG.

  Next, prediction calculation of the acquirable electric energy Y used in step 205 in FIG. 3 will be described with reference to FIG. The acquirable electric energy Y is calculated by the acquirable electric energy calculation means 508 with the power generation characteristics, the regenerative time tb, the charging efficiency, and the target charging amount of the motor generator 102 as input values (504, 505, 506, 507). . The power generation characteristic is calculated by the power generation characteristic calculation means 504 based on the engine speed obtained from the engine speed detection means 110. The regenerative time tb obtained at step 303 in FIG. 4 is used. The charging efficiency is calculated from the battery temperature (501) and the current SOC (502). The target charge amount is calculated from the target SOC (503) and the current SOC. Among these, the target SOC is set according to the vehicle speed. That is, if the vehicle speed is high, it is considered that there are many opportunities for regeneration before the next stop, so the target SOC is set lower than in the case where the vehicle speed is low.

Next, the conversion from the obtainable electric energy Y to the fuel amount Yf performed in step 206 of FIG. 3 will be described. The conversion from the obtainable electric energy Y to the fuel amount Yf is performed by a predetermined constant coefficient C. Yf = C * Y (15)
You may ask as. Alternatively, Yf can be obtained as an additional fuel amount for generating electric power Y by adding torque while the engine is running. For example, assuming that Y is 1/6 [kwh], to charge Y in 1 minute,
(1/6) [kwh] / (1/60) [h] = 10 [kw] (16)
It is necessary to generate electricity at. Assuming that the vehicle speed of the engine running is 50 [km / h], in order to generate 10 [kw], the engine operating point is changed as shown in the fuel consumption / output characteristic diagram of FIG. The torque is increased by 10 kw while maintaining the rotational speed. The change in the fuel injection amount at this time can be obtained by performing the same operating point shift on the fuel injection amount characteristic diagram of FIG. 10, for example, the fuel injection amount is 0.5 by the engine operating point shift. If [cc / sec] increases,
0.5 [cc / sec] * 60 [sec] = 30 [cc] (17)
This amount of fuel is required for power generation. Therefore, Yf in this case can be calculated as 30 [cc].

  Next, the additional running fuel amount Z that is predicted and calculated in step 207 will be described with reference to FIG. In FIG. 11, VSPa and VSPb represent changes in the predicted vehicle speed when regeneration is not performed during the fuel cut, and when regeneration is performed. In FIG. 11, a region surrounded by a line representing the time axis and the vehicle speed represents the travel distance. As described above, since VSPb decreases more quickly than VSPa, the distance traveled from t1 to t3 is shorter when regeneration is performed. When regeneration is performed, in order to reach the same point as when regeneration is not performed, it is necessary to additionally travel a short distance.

  The shortage distance to be supplemented by the additional travel is obtained by integrating (VSPa−VSPb) with respect to t1 to t3, and the amount of fuel necessary to travel the shortage distance is a value Z obtained in step 207. is there. Expected vehicle speeds VSPa and VSPb required at this time are obtained in the vehicle physical model 402 described with reference to FIG.

  If it is predicted that the deficit distance will continue to coast from before t3 and the vehicle speed is not expected to fall below a certain target vehicle speed, the deficit distance should be traveled without using additional energy. (FIG. 11A), and Z = 0. It is conceivable that the target vehicle speed is set to the legal speed of the road on the basis of information from the car navigation system 113. Alternatively, based on the information of the road-to-vehicle communication 114, it may be variably set according to the distance to a forward stop target such as a signal, a preceding vehicle, or a toll booth. When it is predicted that the vehicle speed is lower than the target vehicle speed at a certain timing during inertial running during the additional running (FIG. 11B), additional fuel is consumed from the timing to add engine torque, Assume that the target vehicle speed is achieved by consuming electric power and adding motor torque. In the former case, the required fuel amount corresponds to Z, and in the latter case, a value obtained by converting the required power amount into the fuel amount corresponds to Z. As the conversion method, the same method as in step 206 is used.

The regenerative charge control of the first embodiment described above can be simplified and control can be performed such that regeneration is performed when any of the following conditions or a plurality of combinations are satisfied.
・ Vehicle speed at the start of fuel cut is higher than a predetermined value ・ Engine speed at the start of fuel cut is higher than a predetermined value ・ Battery SOC at the start of fuel cut is lower than a predetermined value ・ During fuel cut Expected road surface slope is downhill greater than the prescribed value ・ Auxiliary equipment usage forecast during fuel cut is less than prescribed value

  The above is the description of the first embodiment.

  Next, an application example to a micro hybrid vehicle equipped with an ISG (Integrated Starter Generator) will be described as a second embodiment of the present invention. The ISG here is connected to the engine by a belt, and in addition to the normal alternator function, it is a device that serves as a starter when the engine is restarted after an idle stop. The ISG is always connected to the engine by an alternator belt, and the engine can be restarted more quickly and quietly than when a normal starter is returned from idle stop. Generally, ISG has a small capacity as a motor, so it is not used to drive a vehicle unlike a mild hybrid, but it actively stores regenerative energy during deceleration and is used to start an engine at idle start. .

  In FIG. 12, the hardware configuration of the charge control device of the ISG-equipped micro hybrid vehicle will be described. The description of the same components as those in the first embodiment is omitted. The second embodiment differs greatly from the first embodiment in that an ISG 601 is mounted instead of the motor generator 102 (FIG. 1), and the connection between the engine 101 and the ISG 601 is not via the clutch 105 (FIG. 1), and the alternator The belt 602 is always connected.

  Next, in FIG. 13, the relationship between the presence or absence of regeneration and the presence or absence of idle stop during fuel cut during deceleration and the trade-off due to the length of the fuel cut period will be described.

  In the fuel cut control described in the first embodiment, the fuel supply is resumed at the timing when the rotational speed is reduced to a predetermined engine rotational speed so that the engine rotational speed does not become equal to or lower than the idle rotational speed, and the idle rotational speed is maintained. It was. However, in this embodiment using idle stop, it is possible to perform control such that the engine speed is decreased and stopped without restarting the fuel supply only when the stop is predicted after deceleration.

  FIG. 13 (i) shows the behavior of fuel supply / cut and engine speed when neither regeneration nor idle stop is performed during fuel cut during deceleration. (Ii) shows the case with no regeneration and idling stop, (iii) shows the case with regeneration and no idling stop, and (iv) shows the case with both regeneration and idling stop. (Ii), (iii), and (iv) also show the amount of power that enters and leaves the battery. In each case, loss assessments regarding the fuel amount and the electric energy from the start of fuel cut to the accelerator ON are shown below.

The fuel cut period in (i) to (iv) of FIG.
tb (iii) <ta (i) <tc (ii, iv) (18)
In (i) and (iii), which have a shorter fuel cut period than (ii) and (iv), an extra fuel amount of xa and xb is required. In (iii) and (iv) in which regenerative charging is performed, the electric energy Y is acquired. On the other hand, in (iii) and (iv), since the vehicle speed decreases more rapidly than in (i) and (ii) in which regenerative charging is not performed, a shortage occurs in the travel distance (not shown). Additional energy is required to travel to the same point as (ii). Further, in (ii) and (iv) in which the idle stop is performed, the electric energy Yrst for engine restart is required. The above energy balance can be summarized as follows.
(I) Consuming fuel amount xa.
(Ii) Consuming electric energy Yrst for engine restart.
(Iii) The electric energy Y is acquired by regeneration. Consumes fuel amount xb and additional travel energy.
(Iv) Acquire electric energy Y by regeneration. Consumes engine restart electric energy Yrst and additional running energy.

  In order to effectively improve the efficiency, it is necessary to predict and calculate these losses and gains and make an optimal selection for regeneration and idle stop.

  The charge control at the time of deceleration fuel cut in consideration of the above will be described below. First, the overall control flow of this embodiment will be described with reference to FIG.

  In step 701, it is determined whether or not a predetermined fuel cut permission condition is satisfied for the engine speed obtained from the engine speed detection means 110 and the accelerator opening obtained from the accelerator opening detecting device 111. If the cut permission condition is satisfied, the fuel is cut (step 702), and if not satisfied, the fuel supply is continued (step 703).

  When the fuel cut is performed, it is determined in the next step 704 whether or not there is an opportunity to idle-stop ahead. This step 704 may be determined based on the information acquired by the road-to-vehicle communication 114, or may be determined by operating the switches by the driver. If it is determined that there is an idle stop opportunity ahead, the process proceeds to step 705. Otherwise, the control is the same as that of the first embodiment already described, and step 204 and subsequent steps in FIG. 3 are performed. The control contents of the first embodiment are omitted here because they overlap.

  If it is determined in step 704 that there is an idle stop opportunity ahead, in step 705, the fuel amounts xa and xb are predicted and calculated (see FIG. 13). These prediction calculation methods will be described later.

  In the next step 706, an acquirable electric energy Y when regenerating is predicted and calculated. Since this prediction calculation method has already been described in the first embodiment, it is omitted here.

  In the next step 707, an electric energy Yrst necessary for restarting the engine is predicted and calculated. Yrst may be a predetermined value or may be estimated from the engine coolant temperature or the like.

  In step 708, the power amounts Y and Yrst predicted and calculated in steps 706 and 707 are converted into the corresponding fuel amounts Yf and Yrstf. Since the conversion method from the amount of electric power to the amount of fuel has already been described in the first embodiment, it is omitted here.

  In step 709, when the regenerative charge is performed during the fuel cut period, the additional travel fuel amount Z necessary for reaching the same point as when the regenerative charge is not performed is predicted and calculated. A method for predicting the additional travel fuel amount Z will be described later.

In step 710, the values prepared so far are used to determine whether or not to perform regeneration and idle stop so as to maximize efficiency. Specifically, the four patterns shown in FIG. 13 are compared in terms of the required fuel amount. The amount of fuel required in each case is:
(I) xa, (ii) Yrstf, (iii) xb-Yf + Z, (iv) Yrstf-Yf + Z
It is. The smallest of these is determined to be optimal, and the corresponding regeneration / idle stop control is performed in step 711.

  By performing predictive calculation and control as described above, it is possible to improve efficiency in terms of fuel consumption, including the presence or absence of idle stop.

  Next, the prediction calculation method of the fuel amounts xa and xb in step 705 in FIG. 14 will be described with reference to FIG.

  The fuel amounts xa and xb are obtained from the fuel injection amount Fidl necessary for maintaining the idle speed and the time required for fuel supply. The fuel injection amount Fidl (801) required for maintaining the idling engine speed is as described in the first embodiment (FIG. 7). In calculating the time required for fuel supply, three types of fuel cut periods ta, tb, and tc in the four cases of FIG. 13 are required. Since the calculation of ta and tb (802, 803) has been described in the first embodiment, a description thereof will be omitted. tc (804) is the time from the start of fuel cut to accelerator ON (FIG. 13). As shown in FIG. 16, the engine restart timing is predicted and set based on the information obtained by road-to-vehicle communication 114. It is decided by doing. The information obtained by the road-to-vehicle communication 114 is, for example, information on how many seconds from now the signal turns blue when waiting for a signal.

Using Fidl, ta, tb, tc, xa and xb are
xa = Fidl * (tc−ta) (19)
xb = Fidl * (tc−tb) (20)
Is required.

  Next, prediction calculation of the additional travel fuel amount Z performed in step 709 will be described. The prediction calculation of the shortage distance to be compensated by the additional running is as described in FIG. 11 of the first embodiment. The additional travel fuel amount Z can be obtained from a fuel injection amount characteristic diagram as shown in FIG. 10, assuming that the vehicle travels the insufficient distance at a predetermined vehicle speed. The predetermined vehicle speed is set to an appropriate low vehicle speed in consideration that the traveling condition is before the stop target.

  The above is the description of the second embodiment.

101 Engine 102 Motor generator 103 Battery 104 Power control device 105 Clutch 106 ECU
107 CVT
108 Final reduction gear 109 Drive wheel 110 Engine rotation speed detection device 111 Accelerator opening detection device 112 Vehicle speed detection device 113 Car navigation system 114 Road-to-vehicle communication 301, 801 Fuel injection amount Fidl calculation means 302 required for maintaining idle rotation speed Fuel cut period ta calculation means 303 in case of not performing fuel cut period tb calculation means 304 in case of regeneration 401 Means for calculating fuel amount X from Ta, Tb, Fidl 401 Means for assuming presence / absence of regeneration 402 Vehicle physical model 403 Fuel cut period ta, tb calculation means 501 Battery temperature detection means 502 Current SOC detection means 503 Target SOC setting means 504 Power generation characteristic detection means 505 Regenerative time detection means 506 Charging efficiency calculation means 507 Target charge amount calculation means 508 Acquiring Calculation of electric energy Means 601 ISG
602 Alternator belt 802 Fuel cut period ta calculation means 803 when there is no regeneration and no idle stop 803 Fuel cut period tb calculation means 804 when there is no idle stop 804 Fuel cut period tc calculation when there is regeneration and there is an idle stop Means 805 Fuel amount xa calculating means 806 Fuel amount xb calculating means 901 Engine restart timing setting means 902 Fuel cut period tc calculating means S201, S701 Step S202 for determining whether or not fuel cut is possible Step S202 Step for implementing fuel cut S203, S703 Step S204 for Fuel Supply Step S205 for Predicting Calculation of Increased Fuel Amount for Regeneration, S706 Step for Predicting Retrievable Electricity Y for Regeneration Step S206 Corresponding to Acquired Electricity Y You Steps S207 and S709 converted to the fuel amount Yf Step S208 for performing prediction calculation of the additional travel fuel amount Z for the short distance when the regeneration is performed Step S209 for comparing the increased fuel amount X with the acquirable power equivalent fuel amount Yf Step S702 to be performed Step S704 to perform fuel cut execution Step S705 to determine whether or not there is an idle stop opportunity Prediction of the amount of fuel (xa, xb) that is required more when there is no idle stop than when the idle stop is performed Step S707 for performing calculation Step S708 for predicting and calculating the electric energy Yrst necessary for engine restart Step S710 for converting the obtainable electric energy Y and the electric energy Yrst necessary for engine restart into the corresponding fuel amounts Yf and Yrstf Implementation / non-execution of each idle stop Step S711 for determining implementation Step for implementing / not implementing regeneration and idle stop

Claims (14)

A charge control device mounted on a hybrid vehicle including an engine as a driving force source and a motor generator having a function as a driving force source and a generator,
Before starting the fuel cut of the hybrid vehicle,
Saving with and without regeneration by the motor generator based on the expected fuel cut period from the current engine speed to the idle speed when the motor generator performs regeneration and when it does not perform regeneration A saving fuel amount difference prediction means for predicting a difference in fuel amount;
An acquired electric energy predicting means for predicting an electric energy acquired when performing regeneration;
An acquired power fuel amount conversion means for obtaining an equivalent fuel amount corresponding to the power amount predicted by the acquired power amount prediction means;
A charge control apparatus comprising: a regeneration presence / absence determining unit that determines whether or not regeneration is performed by the motor generator based on the difference in the saved fuel amount and the equivalent fuel amount.   The fuel saving amount difference predicting means according to claim 1, wherein the fuel injection amount per unit time required for maintaining the idle speed of the engine of the hybrid vehicle, and the predicted fuel when the regenerative charging is performed and when not performed, respectively. A charge control device that calculates a difference in the amount of saved fuel based on the cut period.   The predicted fuel cut period according to claim 1 is performed by performing the engine speed at the start of the fuel cut, the vehicle speed at the start of the fuel cut, the prediction of the road condition at the start of the fuel cut, and the regenerative charging. A charge control device characterized by being predicted and calculated in a vehicle physical model using a load magnitude as an input.   The acquired power amount predicting means according to claim 1, wherein the engine speed at the start of the fuel cut, the vehicle speed at the start of the fuel cut, the battery temperature at the start of the fuel cut, and the battery charge at the start of the fuel cut. A charge control device that predicts the amount of acquired electric power based on a state and the predicted fuel cut period.   The acquired power fuel amount conversion means according to claim 1 calculates the fuel amount that is additionally required when charging the acquired power amount while the engine is running based on the fuel consumption characteristic specific to the engine. A charge control device that performs conversion from fuel to fuel amount.   The regeneration presence / absence determining means according to claim 1 includes a vehicle speed at the start of the fuel cut, an engine speed at the start of the fuel cut, a battery charge state at the start of the fuel cut, and a road ahead at the start of the fuel cut. A charge control device characterized in that the presence or absence of regeneration is determined by one or a combination of situation prediction and auxiliary equipment usage amount prediction at the start of fuel cut satisfying a predetermined condition. A charge control device mounted on a vehicle equipped with an idle stop function including an engine as a driving force source, and an alternator having a function as a generator and a start function of the engine,
Before starting the fuel cut,
In the case of not performing idle stop for each of the four cases of performing regeneration with the motor generator and performing idle stop and not performing and performing idle stop without performing regeneration, the current engine Predicted fuel amount difference prediction means for predicting the difference in the amount of fuel to be saved based on the time from the start of fuel cut to the restart in the case of performing the expected fuel cut period from the rotation speed to the idle rotation speed or when performing idle stop When,
An acquired electric energy predicting means for predicting an electric energy acquired when performing regeneration;
An acquired power fuel amount conversion means for obtaining an equivalent fuel amount 1 corresponding to the power amount predicted by the acquired power amount prediction means;
Restart power fuel amount conversion means for converting the amount of power required for engine restart when the idle stop is performed into an equivalent fuel amount 2;
Regenerative / idle stop presence / absence determining means for determining whether the motor generator performs regeneration and whether to perform idle stop based on the difference in the saved fuel amount and the equivalent fuel amount 1 and the equivalent fuel amount 2; A charge control device.   The fuel saving amount difference prediction means according to claim 7, wherein the fuel injection amount per unit time required for maintaining the idle speed of the engine of the vehicle equipped with the idle stop function, and when performing the regenerative charging, respectively, A charge control device that calculates an amount of fuel to be saved based on an expected fuel cut period and a period from the start of fuel cut to a restart.   9. The expected fuel cut period and the time from the start of fuel cut to the restart are the engine speed at the start of the fuel cut, the vehicle speed at the start of the fuel cut, and the road ahead at the start of the fuel cut. A charge control device characterized in that prediction calculation is performed in a vehicle physical model using a situation prediction and a load size due to the regenerative charging as inputs.   The idle period according to claim 8, wherein the period from the start of fuel cut to the restart is predicted and set based on information obtained by road-to-vehicle communication between the vehicle equipped with the idle stop function and road infrastructure. Charge control device for vehicles with stop function.   The acquired power amount predicting means according to claim 7, wherein the engine speed at the start of the fuel cut, the vehicle speed at the start of the fuel cut, the battery temperature at the start of the fuel cut, and the battery charge at the start of the fuel cut. A charge control device that predicts an acquired electric energy based on a state and an expected fuel cut period when performing regenerative charging according to claim 8.   The acquired electric power fuel amount conversion means according to claim 7 calculates an additional fuel amount required when charging the acquired electric power amount while the engine is running based on a fuel consumption characteristic specific to the engine. A charge control device that performs conversion from fuel to fuel amount.   The restart electric power fuel amount conversion means according to claim 7 is configured to calculate an additional fuel amount required for charging the electric energy required for restarting the engine while the engine is running based on a fuel consumption characteristic specific to the engine. A charge control device for a vehicle equipped with an idle stop function, wherein a conversion from an electric power amount to a fuel amount is performed by calculation. In claim 1 or 7,
A charge control device that predicts the amount of fuel for additional travel required when regenerating, and uses the amount of fuel for determining whether or not regeneration is performed or whether or not there is an idle stop.

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