JP2015120482A - Hybrid vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hybrid vehicle control device which properly warms up a catalyst by avoiding the lowering of fuel economy when there arise both a catalyst warmup requirement and an SOC control requirement while securing a charging capacity of a battery.SOLUTION: When a catalyst warmup control flag is turned on (S10: YES), and a low-SOC control flag is turned on(S12: YES), an ECU (hybrid vehicle control device) calculates regenerative power Preg_av, charging allowable power Win, and vehicle traveling power Prun (S13), and calculates battery charging/discharging power Pbatt on the basis of a difference between the regenerative power Preg_av and the charging allowable power Win (S14). Furthermore, the ECU calculates engine requirement output Peng by subtracting the battery charging/discharging power Pbatt from the vehicle traveling power Prun (S15), and performs ignition retardant control by setting an ignition retardant angle IGTrtd (S16, S18). By this constitution, a catalyst can be properly warmed up while taking the charging allowable power Win into consideration.

Description

  The present invention relates to a hybrid vehicle control apparatus capable of controlling output of an engine and a motor generator and charging / discharging of a battery in a hybrid vehicle.

  In recent years, a hybrid vehicle equipped with an engine and a motor generator as a driving force source of a vehicle has attracted attention because of the social demand for low fuel consumption and low exhaust emissions. There is also known a control device that performs catalyst warm-up control when the temperature of a catalyst that purifies engine exhaust is lower than a predetermined temperature.

For example, in the control device disclosed in Patent Document 1, in a hybrid vehicle using a lithium ion battery as a battery, a low SOC control request is output when the battery temperature is lower than a predetermined temperature, and the SOC management center is a normal value ( For example, the allowable charging power (input limit) Win of the battery is increased by lowering the value from 60% to a slightly smaller value (for example, 45%).
When the catalyst temperature is lower than a predetermined temperature, a catalyst warm-up request is output. When the catalyst warm-up request is output, the catalyst warm-up control mode is set regardless of the output of the low SOC control request, and the engine is operated so as to be operated independently at idle speed (no load operation) with the ignition retarded. By controlling, the catalyst is warmed up. That is, when both the battery temperature and the catalyst temperature are low, the deterioration of the emission is suppressed by giving priority to the catalyst warm-up control over the low SOC control.

JP 2008-284909 A

  When there is both a catalyst warm-up request and a low SOC control request, the control device of Patent Document 1 has a large reduction in fuel consumption because the engine is operated without load. Further, since the allowable charging power Win is not increased due to the decrease in the SOC, there is a possibility that the energy during the deceleration regeneration of the motor generator cannot be sufficiently charged to the battery.

  The present invention was created in view of the above points, and its purpose is to avoid a decrease in fuel consumption and to secure a battery charging capacity when both a catalyst warm-up request and a low SOC control request are present. However, an object of the present invention is to provide a hybrid vehicle control device that appropriately warms up the catalyst.

The present invention relates to an engine, a catalyst that is provided in an exhaust pipe, purifies exhaust, a motor generator that can generate driving force by consuming electric power by a power running operation, and that can generate electric power by a regenerative operation, and a motor generator In a hybrid vehicle equipped with a battery that can be charged and discharged by receiving and transferring electric power with the battery, a “catalyst warm-up request” for warming up the catalyst, and a charge allowable power (Win) by reducing the SOC management center of the battery ) Is an invention relating to a hybrid vehicle control device capable of controlling the driving of the engine and the motor generator and the charging / discharging of the battery in accordance with the “low SOC control request”.
Here, “battery” means a general power storage device that can be charged and discharged, and includes a capacitor and the like.

In this hybrid vehicle control device, when there is both a catalyst warm-up request and a low SOC control request, the regenerative power (Preg_av) that may be generated by the regenerative operation of the motor generator and changes according to the vehicle speed is determined by the battery temperature. (Tb) The engine is loaded while being controlled to be within the allowable charging power range determined by (Tb) and SOC, and the exhaust heat energy (Eexh) supplied to the catalyst exceeds the catalyst warm-up required energy (Eexhtgt) Thus, “catalyst warm-up control” for warming up the catalyst is executed.
Here, the exhaust heat energy is obtained, for example, as an integrated value of the exhaust heat flow (Qexh) calculated based on the exhaust temperature and the exhaust flow rate.

In the present invention, as in the prior art of Patent Document 1, the catalyst warm-up control is prioritized over the low SOC control at the time of catalyst warm-up request, and the engine is not loaded with no load. Since the engine is warmed up, a reduction in fuel consumption can be avoided.
In addition, control is performed so that the regenerative power is within the range of allowable charging power. Specifically, the battery is charged / discharged according to the power balance (Preg_av−Win), which is a power value obtained by subtracting the allowable charging power from the regenerative power, and the charging allowable power Win is expanded when the battery is discharged, thereby All the energy during deceleration regeneration by the generator can be charged to the battery. Therefore, the catalyst can be appropriately warmed up while ensuring the charging capacity of the battery.

  The hybrid vehicle control device of the present invention preferably calculates the vehicle travel power (Prun) necessary for traveling of the hybrid vehicle when both the catalyst warm-up request and the low SOC control request exist. (1) When the vehicle speed (V) is lower than a predetermined vehicle speed threshold value (Vx) and the regenerative power is smaller than the charge allowable power, the engine output (Peng) is made larger than the vehicle running power to charge the battery. . (2) When the vehicle speed is higher than the vehicle speed threshold value and the regenerative power is larger than the allowable charging power, the engine output is made smaller than the vehicle running power to discharge the battery.

In the case of the control (1), the SOC increases when the battery is charged, but the chargeable power has a margin for the regenerative power, and the objectives of both the low SOC control and the catalyst warm-up control are achieved simultaneously. .
In the case of the control (2), the SOC decreases due to the battery discharge, and the regenerative power can be controlled so as to be within the range of the allowable charging power. Therefore, the purpose of both the low SOC control and the catalyst warm-up control is Achieved at the same time.

  Further, in the catalyst warm-up control of the present invention, the exhaust heat energy is increased by carrying out “ignition delay control” in which the ignition timing of the engine is retarded by a predetermined ignition retard amount (IGTrtd). It is preferable to warm up. As a result, the exhaust heat energy can be increased in a shorter time and the catalyst can be warmed up earlier than in the method of increasing the exhaust heat energy only by increasing the exhaust flow rate.

Assuming ignition retard control, the battery is preferably charged by the control (1) described above, and the ignition retard amount is made relatively smaller than the control (2). Further, in the control (2), the battery is discharged, and the ignition retard amount is made relatively larger than the control (1).
In the case of the control (1), the ignition retard amount is set to be small, and the catalyst is warmed up early by mainly increasing the exhaust heat flow by increasing the exhaust flow rate. Thereby, it is possible to avoid a reduction in fuel consumption when the catalyst is warmed up, and to promote warming up of the catalyst and the engine.
In the case of the control (2), the ignition delay amount is set to be large, and the catalyst is warmed up early by mainly increasing the exhaust heat flow due to the ignition delay effect.

1 is a system diagram of a hybrid vehicle to which a hybrid vehicle control device according to an embodiment of the present invention is applied. The flowchart of the catalyst warm-up control by one Embodiment of this invention. The map which shows the relationship between vehicle speed V and regenerative power Preg_av. The map which shows the relationship between battery temperature Tb and SOC, and charge allowable electric power Win. The map which shows the relationship between power balance (Preg_av-Win) and battery charging / discharging electric power Pbatt. The map which shows the relationship between ignition retard amount IGTrtd and exhaust thermal efficiency (eta) exh. The time chart of the catalyst warm-up control by one Embodiment of this invention.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a hybrid vehicle control device of the present invention will be described with reference to the drawings.
(One embodiment)
First, an example of a hybrid vehicle to which the hybrid vehicle control device of the present invention is applied will be described with reference to FIG. A hybrid vehicle 10 shown in FIG. 1 is a so-called series parallel hybrid vehicle including an engine 2 and two motor generators (shown as “MG” in the figure) 31 and 32 as a driving force source. A hybrid vehicle to which the control device of another embodiment is applied only needs to include at least one motor generator.

  The engine 2 is, for example, a 4-cylinder engine that outputs power by burning fuel such as gasoline or light oil. The engine 2 generates power by causing an air-fuel mixture of air sucked through the throttle valve and fuel injected from the fuel injection valve to explode and burn with electric sparks from the spark plug. Note that the throttle valve, the fuel injection valve, and the spark plug are not shown. Exhaust gas from each cylinder of the engine 2 is collected in the exhaust pipe 22 via the exhaust manifold 21, purified by the catalyst 23 provided in the exhaust pipe 22, and then discharged into the atmosphere.

  In the example of the hybrid vehicle 10, the power of the engine 2 is transmitted to the power split mechanism 16 via the crankshaft 15. The power split mechanism 16 splits the power of the engine 2, drives the wheels 14 with one power, and causes the first motor generator 31 to generate power with the other power. Note that the control device of another embodiment may be applied to a hybrid vehicle that does not include a power split mechanism.

The motor generators 31 and 32 are, for example, permanent magnet type synchronous three-phase AC motors, and are connected to batteries via inverters 33 and 34 (indicated as “INV” in the figure) for converting DC power and three-phase AC power. 4 is electrically connected.
The motor generators 31 and 32 can generate power by consuming electric power by a power running operation and can generate electric power by a regenerative operation. The first motor generator 31 is driven by the inverter 33, functions as a generator that generates power mainly by the driving force of the engine 2, and charges the battery 4 with the generated power. The second motor generator 32 is driven by the inverter 34 and functions as an electric motor that drives the wheels 14 via the axle 13 by consuming the electric power discharged from the battery 4 mainly by a power running operation. The second motor generator 32 performs a regenerative operation when the hybrid vehicle 10 decelerates, and charges the battery 4 with the generated power.

The battery 4 is a chargeable / dischargeable power storage device such as a nickel hydride or lithium ion battery. Further, it is assumed that the battery 4 includes a power storage device such as an electric double layer capacitor.
The battery 4 can be charged / discharged by receiving / transmitting electric power from / to the motor generators 31 and 32, and charged in a range where SOC (State Of Charge) is within a predetermined limit amount.

The direct current power of the battery 4 is converted into three-phase alternating current power by the inverter 34 and supplied to the second motor generator 32. In addition, the direct current power of the battery 4 is converted to low voltage direct current power by a DCDC converter, for example. Used as
In an actual hybrid vehicle, the battery 4 is also called a “main machine battery” or a “high voltage battery” in order to distinguish it from a low voltage battery for auxiliary equipment. However, in this specification, the battery for auxiliary equipment is not particularly referred to, and therefore simply referred to as “battery 4”.

The ECU 5 corresponds to the “hybrid vehicle control device” of the present invention, and receives signals such as the vehicle speed and the accelerator opening degree by the driver's accelerator operation, and the engine 2, catalyst 23, motor generators 31 and 32, battery Information such as the current operating state, temperature, SOC, etc., such as 4 is acquired, and the driving of each driving force source is comprehensively controlled and managed.
In an actual hybrid, the ECU 5 is an engine ECU, MG-ECU, battery ECU, or other individual ECU that is assigned control for each control target, and communicates with these individual ECUs to manage the entire vehicle in an integrated manner. PM (Power Management) -A plurality of control devices such as an ECU. However, in this specification, detailed control sharing is not mentioned, and the ECU 5 as a comprehensive control device executes all the controls described later.

The main operation of the ECU 5 will be described. The ECU 5 is attached to the engine 2 in the vicinity of the crank angle, the cooling water temperature, the cylinder pressure, the cam angle, the throttle opening, the intake air amount, the intake / exhaust temperature, the air / fuel ratio, the oxygen signal, and the catalyst 23 in the exhaust pipe 22. Information such as the catalyst temperature Tcat from the obtained catalyst temperature sensor 24 is acquired, and various control amounts are calculated based on the information. The catalyst temperature sensor 24 may not be provided, and the catalyst temperature Tcat may be estimated from, for example, the engine stop period and the outside air temperature.
The ECU 5 outputs a drive signal to the fuel injection valve, a drive signal to the throttle motor that adjusts the opening of the throttle valve, a control signal to the spark plug, a control signal to the valve timing adjustment device, etc. The operation of the engine 2 is controlled.

Further, the ECU 5 calculates a torque command for the motor generators 31 and 32 based on the vehicle speed signal and the accelerator opening signal, and further based on the electrical angle signal from the rotation angle sensor, the current feedback signal from the current sensor, and the like. Thus, the energization of the motor generators 31 and 32 is controlled by controlling the switching operation of the inverters 33 and 34.
Further, the ECU 5 acquires information on the battery 4 such as the battery temperature Tb and the SOC, and performs control so as to appropriately charge and discharge within the range of the allowable charging power (input limit) Win and the allowable discharging power (output limit) Wout. .

  In the hybrid vehicle configured as described above, in the conventional technology of Patent Document 1, since the allowable charge power Win decreases when the battery temperature Tb is low, the SOC management center is slightly smaller than the normal value (for example, 60%). By reducing the value to a value (for example, 45%), a “low SOC control request” for expanding the charge allowable power (input limit) Win of the battery is output. When the catalyst temperature Tcat is lower than the predetermined temperature, a catalyst warm-up request is output. When both the catalyst warm-up request and the low SOC control request are present, the catalyst warm-up control is prioritized over the low SOC control, and the engine is controlled so that the engine is operated independently at idle speed (no load operation) with the ignition retarded. To warm up the catalyst.

However, in this prior art, the fuel consumption is greatly reduced because the engine is operated without load. Further, since the allowable charging power Win is not increased due to the decrease in the SOC, there is a possibility that the energy during the deceleration regeneration of the motor generator cannot be sufficiently charged to the battery.
Therefore, in order to solve the above-described problem, the ECU 5 of the present embodiment avoids a decrease in fuel consumption and appropriately secures the battery charging capability when both the catalyst warm-up request and the low SOC control request exist. The control for warming up the catalyst is performed.

Next, a catalyst warm-up control routine executed by the ECU 5 of the present embodiment will be described with reference to FIGS. In the description of the flowchart below, the symbol “S” means a step. In the description of the control, if the reference numerals in FIG. 1 are written in all of the engine, battery, motor generator, etc., the text becomes difficult to read.
First, it is determined in S10 whether the catalyst warm-up control flag is ON, that is, whether there is a catalyst warm-up request. When the catalyst warm-up control flag is OFF (S10: NO), the following steps are not executed and the process is terminated. When the catalyst warm-up control flag is ON (S10: YES), the process proceeds to the following steps.

  In S11, based on the deviation between the target catalyst temperature Ttgt and the current catalyst temperature Tcat, a catalyst warm-up required energy Eexhtgt which means “exhaust heat energy necessary for activating the catalyst” is calculated using a map or the like. . The target catalyst temperature Ttgt is set in advance as a temperature necessary for catalyst activity. As the current catalyst temperature Tcat, a value detected by a temperature sensor or a value estimated based on an engine stop period, an outside air temperature, or the like is used. The map is created in advance based on the heat capacity of the catalyst, the outside air temperature, and the like.

In S12, it is determined whether the low SOC control flag is ON, that is, whether there is a low SOC control request. When there is a low SOC control request (S12: YES), the process proceeds to S13 in order to perform the catalyst warm-up control in consideration of the charge allowable power Win. When there is no low SOC control request (S12: NO), the process proceeds to S17.
In S13, regenerative power Preg_av, charge allowable power Win, and vehicle travel power Prun are calculated.

The regenerative power Preg_av is electric power that may be generated by a regenerative operation of the motor generator when the vehicle is decelerated, and is calculated using a characteristic map of the vehicle speed V and the regenerative power Preg_av shown in FIG. Note that the subscript “reg” of “Preg_av” means “regeneration”, and “av” means “available”.
As shown in FIG. 3, the regenerative power Preg_av increases as the vehicle speed V increases. Therefore, in the relationship with the allowable charging power Win, the regenerative power Preg_av is smaller than the allowable charging power Win in the region lower than the vehicle speed threshold Vx, and the regenerative power Preg_av is the allowable charging power Win in the region higher than the vehicle speed threshold Vx. Become bigger.

  Charging allowable power Win is calculated using a characteristic map of battery temperature Tb and charging allowable power Win shown in FIG. As shown in FIG. 4, when the battery temperature is lower than Tb0 on the low temperature side or higher than Tb2 on the high temperature side, charging / discharging is not possible, and charging is performed according to the battery temperature Tb and SOC in the range of the battery temperature from Tb0 to Tb1. The allowable power (input limit) Win and the discharge allowable power (output limit) Wout change.

For example, paying attention to the IVp portion indicating the charging side (power negative side) where the battery temperature Tb is around 0 ° C., the allowable charging power Win that is the absolute value of power as the SOC decreases from 60% to 50% and 40%. It can be seen that increases.
The vehicle travel power Prun is calculated as a power required for travel based on at least the accelerator opening, the vehicle speed, and the like.

  Here, the “power value obtained by subtracting the allowable charging power Win from the regenerative power Preg_av” is referred to as “power balance (Preg_av−Win)” for convenience. In S14, based on the power balance (Preg_av-Win), the battery charge / discharge power Pbatt is calculated using the map shown in FIG. The battery charge / discharge power Pbatt is the charge / discharge required for the battery to load the engine in a state where the regenerative power Preg_av is within the range of the charge allowable power Win, that is, the power balance (Preg_av−Win) is negative. Of power. When the battery charge / discharge power Pbatt is positive, it means discharge, and when it is negative, it means charge.

As described above, the power balance (Preg_av−Win) is larger as the vehicle speed is higher or the SOC is higher, and is smaller as the vehicle speed is lower or the SOC is lower. Therefore, the battery is basically required to be discharged when the power balance (Preg_av-Win) is large, and to be charged when the power balance (Preg_av-Win) is small.
However, in the map of FIG. 5, when the power balance (Preg_av−Win) is 0, the charging / discharging inversion position is not set, and when the power balance (Preg_av−Win) is 0, the discharge is set to some extent. A dead zone DZ that is not charged / discharged is provided in a negative region of the power balance (Preg_av-Win). As a result, the regenerative power Preg_av is stabilized at a value lower than the charge allowable power Win by a predetermined amount.

In S15, the engine request output Peng at the time of engine load operation is calculated by the equation (1).
Peng = Prun−Pbatt (1)
When the battery charge / discharge power Pbatt is positive, the engine required output Peng during engine load operation is smaller than the vehicle travel power Prun. When the battery charge / discharge power Pbatt is negative, the engine request output Peng during engine load operation is the vehicle travel power. It becomes larger than power Prun.

S16 to S18 are steps for substantially warming up the catalyst. In the present embodiment, as a method for warming up the catalyst, “ignition delay control” is performed in which the ignition timing of the engine is retarded by a predetermined ignition delay amount IGTrtd. The unit of the ignition retard amount IGTrtd is the cam shaft angle [° CA].
In S16, the ignition retard amount IGTrtd is calculated using a map based on the engine required output Peng that is related to the exhaust flow rate and is calculated in S15 and the engine water temperature thw that is related to the warm-up state of the engine.

On the other hand, in S17 which proceeds when there is no low SOC control request (S12: NO), the engine load eloload which is related to the exhaust flow rate and used in normal engine control and the engine water temperature thw which is related to the warm-up state of the engine. Based on the map, the ignition retard amount IGTrtd is calculated using the map.
When the ignition retard amount IGTrtd is thus set in S16 or S17, the process proceeds to S18. In S18, the engine is operated by igniting the ignition timing obtained by retarding the ignition delay amount IGTrtd set in S16 or S17 with respect to the normal engine ignition timing calculated separately.

In S19, exhaust heat energy Eexh supplied to the catalyst is calculated. Two methods will be described as this calculation method.
The first method is a calculation method based on the exhaust heat efficiency ηexh. As shown in the map of FIG. 6, when the ignition delay amount IGTrtd is increased, the thermal energy supplied to the exhaust increases, and the exhaust thermal efficiency ηexh increases. On the other hand, the engine shaft efficiency ηeng decreases. Therefore, the exhaust thermal efficiency ηexh is calculated from the ignition retard amount IGTrtd using a map that is created by experimentally obtaining the characteristics of the exhaust thermal efficiency ηexh with respect to the ignition retard amount IGTrtd.

Further, the injection fuel heat flow Qinj is calculated from the equation (2.1), and the correction coefficient considering the exhaust heat efficiency ηexh, the heat loss to the exhaust pipe, and the like is further calculated from the equation (2.2). The exhaust heat flow Qexh is calculated by multiplying α. And exhaust heat energy Eexh is obtained by integrating | accumulating the exhaust heat flow Qexh by Formula (2.4).
Qinj = injection amount × heat generation amount of fuel (2.1)
Qexh = Qinj × ηexh × α (2.2)
Eexh = Σ (Qexh) (2.4)

The second method is a calculation method from the exhaust temperature and the exhaust flow rate. Based on the exhaust temperature detected by the exhaust temperature sensor installed upstream of the catalyst in the exhaust pipe and the exhaust flow rate, the exhaust heat flow Qexh is calculated by the equation (2.3). Further, the exhaust flow rate may be regarded as substantially equal to the engine intake air amount, and the engine intake air amount may be substituted. Similarly to the first method, the exhaust heat energy Eexh is obtained by integrating the exhaust heat flow Qexh by the equation (2.4).
Qexh = constant specific heat of exhaust x (exhaust temperature-outside air temperature) x exhaust flow rate (2.3)
Eexh = Σ (Qexh) (2.4)

In S20, the catalyst warm-up required energy Eexhtgt set in S11 is compared with the exhaust heat energy Eexh supplied to the catalyst calculated in S19. When the exhaust heat energy Eexh supplied to the catalyst is equal to or less than the catalyst warm-up required energy Eexhtgt (S20: NO), it is determined that the catalyst warm-up is not completed, and the control routine is terminated while the catalyst warm-up control flag remains on.
On the other hand, when the exhaust heat energy Eexh exceeds the catalyst warm-up required energy Eexhtgt (S20: YES), it is determined that the catalyst warm-up is completed, the ignition retard amount IGTrtd is cleared (S21), and the catalyst warm-up control is performed. The flag is turned off (S22). Thereby, in the routine after the next time, it is determined NO in S10, and the execution of the catalyst warm-up control is prohibited.

  Next, the behavior of the hybrid vehicle realized by the catalyst warm-up control will be described with reference to the time chart of FIG. In the time charts shown in FIGS. 7A to 7I, the horizontal axis is the common time axis, and (a) the low SOC control flag ON / OFF, (b) the catalyst warm-up control flag ON / OFF, and (c). Vehicle speed, (d) engine speed, (e) ignition delay amount IGTrtd, (f) travel power Prun and engine required output Peng, (g) chargeable power Win and regenerative power Preg_av, (h) SOC, (i ) Exhaust heat energy Eexh is the vertical axis. Hereinafter, in the description, reference symbols (a) to (i) to be referred to and related steps of the flowchart (FIG. 2) are described.

Low SOC control is required throughout the period represented by this time chart, and the low SOC control flag is always ON (a). The actual SOC is higher than the target management center SOC ^* by the low SOC control (h).
When the engine is started at time t1 (d), the catalyst warm-up control flag is turned ON (b) because the catalyst temperature is lower than the predetermined temperature. Then, according to S11 of the flowchart, the catalyst warm-up required energy Eexhtgt is calculated (i).

  Further, according to S13, the regenerative power Preg_av is calculated from the vehicle speed V (g). At this time, the regenerative power Preg_av has a margin with respect to the charge allowable power Win, that is, the power balance (Preg_av−Win) is sufficiently negative. Therefore, in S14, the battery charge / discharge power Pbatt is a negative value (charge). ). Then, the engine required output Peng is set to a value larger than the vehicle running power Prun by the battery charge / discharge power Pbatt (f), and the engine is operated by reflecting the ignition delay amount IGTrtd (e) calculated in S16. Thereby, the exhaust heat energy Eexh starts to increase, and the catalyst is warmed up (i).

Between time t1 and time t2, the battery charge / discharge power Pbatt is on the charging side, so the SOC gradually increases during traveling and the charge allowable power Win decreases (g).
Near the time t2, the regenerative power Preg_av approaches the charge allowable power Win. Therefore, in S14, the battery charge / discharge power Pbatt is set to 0, and the vehicle travel power Prun and the engine request output eng are matched (f).

From time t2 to time t3, the regenerative power Preg_av increases as the vehicle speed V increases (c). However, by setting the battery charge / discharge power Pbatt to the discharge side (f) and decreasing the SOC (h), the regenerative power Preg_av is controlled to be within the range of the charge allowable power Win (g). By this control, the SOC eventually approaches the target management center SOC ^* , and the same effect as the low SOC control can be obtained.
Further, the exhaust heat energy Eexh continuously increases and the catalyst is warmed up (i).

  When the exhaust heat energy Eexh reaches the catalyst warm-up required energy Eexhgt at time t3 (i), it is determined that the catalyst warm-up has been completed (S20: YES). Therefore, the ignition delay amount IGTrtd is cleared in S21 and S22 (e), and the catalyst warm-up control flag is turned OFF (b).

Next, the effect by this embodiment is demonstrated.
When both the catalyst warm-up request and the low SOC control request are present, the ECU (hybrid vehicle control device) of the present embodiment sets the power balance (Preg_av−Win) that is the difference between the regenerative power Preg_av and the charge allowable power Win. Based on this, the battery charge / discharge power Pbatt is calculated, and the battery warm-up control is executed while adjusting the engine required output Peng by appropriately charging and discharging the battery.

  Specifically, refer to FIG. In a region where the vehicle speed V is lower than the vehicle speed threshold Vx and the power balance is negative (Preg_av−Win <0), all the energy during deceleration regeneration by the motor generator can be received by the battery. There is little need to expand.

Therefore, the engine output Peng is increased, the exhaust gas flow rate is increased, and the ignition retard amount IGTrtd is set to be small. That is, mainly by increasing the exhaust heat flow Qexh by increasing the exhaust flow rate and operating at a point with good engine efficiency, it is possible to avoid a decrease in fuel consumption when the catalyst is warmed up, and also to warm up the catalyst and engine. Can be promoted.
At this time, the engine output Peng is larger than the traveling power Prun, and the battery charge / discharge power Pbatt is negative. That is, the electric power obtained by subtracting the traveling power Prun from the engine output Peng is charged from the motor generator to the battery.

  On the contrary, in the region where the vehicle speed V is higher than the vehicle speed threshold value Vx and the power balance is positive (Preg_av−Win> 0), the energy during deceleration regeneration by the motor generator cannot be received by the battery. There is a need to expand the chargeable power Win by reducing the power. In this case, since the vehicle speed V is high and the traveling power Prun is relatively large, it is easy to reduce the SOC even while the engine is loaded.

In reducing the engine output Peng, the ignition retard amount IGTrtd is set to a larger value and increased. That is, the engine shaft efficiency ηeng is prevented from being extremely lowered by continuing the load operation while promoting the catalyst warm-up by increasing the exhaust heat flow Qexh mainly by the ignition delay effect. Thereby, a reduction in fuel consumption can be avoided.
At this time, the engine output Peng is smaller than the traveling power Prun, and the battery charge / discharge power Pbatt is positive. That is, the electric power obtained by subtracting the engine output Peng from the running power Prun is discharged from the battery to the motor generator and used as the driving force of the motor generator.

In short, in the present embodiment, as in the prior art of Patent Document 1, when the catalyst warm-up is requested, the engine warm-up control is prioritized over the low SOC control and the engine is not loaded, but the engine is loaded. However, since the catalyst is warmed up, a reduction in fuel consumption can be avoided.
Further, by charging / discharging the battery according to the power balance (Preg_av−Win) and expanding the charge allowable power Win when the battery is discharged, it is possible to charge the battery with all the energy during deceleration regeneration by the motor generator. To. Therefore, the catalyst can be appropriately warmed up while ensuring the charging capacity of the battery.

  In the present embodiment, the exhaust gas thermal efficiency Eexh is increased by increasing the exhaust thermal efficiency ηexh or the exhaust gas temperature by performing ignition delay control that retards the ignition timing, and the catalyst and the engine are warmed up. Thereby, compared with the method of increasing the exhaust heat energy Eexh only by increasing the exhaust flow rate, the exhaust heat energy Eexh can be increased in a short time and the catalyst can be warmed up early.

(Other embodiments)
(A) In FIG. 1 of the above embodiment, as an example of a hybrid vehicle to which the control device of the present invention is applied, a so-called series parallel hybrid provided with an engine 2, two motor generators 31 and 32, and a power split mechanism 16. Showed the car. The hybrid vehicle to which the control device of the present invention is applied is not limited to this, and any other configuration may be used as long as it includes an engine, one or more motor generators, a battery, and a catalyst. For example, a configuration having low relevance to the technical features of the present invention, such as a clutch, a transmission, and a differential gear mechanism, may be freely selected.

(A) The method for warming up the catalyst and the engine is not limited to ignition retard control, and a method such as increasing the amount of intake air to the engine may be implemented.
(C) The map used for calculating the ignition retard amount IGTrtd in S16 and S17 in the flowchart of FIG. 3 is not limited to the map based on the engine required output Peng or the engine load eload and the engine water temperature thw, but other “exhaust flow rate and It may be based on “related parameters” and “parameters related to engine warm-up condition”.
As mentioned above, this invention is not limited to the said embodiment at all, In the range which does not deviate from the meaning of invention, it can implement with a various form.

10 ... Hybrid car,
2 ... Engine,
22 ... exhaust pipe, 23 ... catalyst,
31, 32... Motor generator,
4 ... Battery,
5 ... ECU (hybrid vehicle control device).

Claims (6)

Engine (2),
A catalyst (23) provided in the exhaust pipe (22) for purifying exhaust;
Motor generators (31, 32) capable of generating driving force by consuming electric power by power running operation and generating electric power by regenerative operation;
A battery (4) that can be charged and discharged by transferring power to and from the motor generator;
In a hybrid vehicle (10) including: a catalyst warm-up request for warming up the catalyst, and a low SOC control request for increasing chargeable power (Win) by lowering the SOC management center of the battery A hybrid vehicle control device (5) capable of controlling driving of the engine and the motor generator and charging / discharging of the battery,
When both the catalyst warm-up request and the low SOC control request are present,
The regenerative power (Preg_av) that may be generated by the regenerative operation of the motor generator and changes according to the vehicle speed is controlled to be within the range of the charge allowable power determined by the battery temperature (Tb) and the SOC. Catalyst warm-up control is performed to warm the catalyst so that the engine is loaded and exhaust heat energy (Eexh) supplied to the catalyst exceeds catalyst warm-up required energy (Eexhtgt). A hybrid vehicle control device. When both the catalyst warm-up request and the low SOC control request are present,
Calculate the vehicle running power (Prun) required for running the hybrid vehicle,
When the vehicle speed (V) is lower than a predetermined vehicle speed threshold value (Vx) and the regenerative power is smaller than the charging allowable power, the engine output (Peng) is made larger than the vehicle running power to charge the battery,
2. The battery according to claim 1, wherein when the vehicle speed is higher than the vehicle speed threshold and the regenerative power is greater than the chargeable power, the battery is discharged by making the engine output smaller than the vehicle travel power. Hybrid vehicle control device. In the catalyst warm-up control,
3. The hybrid vehicle according to claim 1, wherein the exhaust heat energy is increased by performing ignition delay control that retards the ignition timing of the engine by a predetermined ignition delay amount (IGTrtd). 4. Control device. When both the catalyst warm-up request and the low SOC control request are present,
Calculate the vehicle running power (Prun) required for running the hybrid vehicle,
When the vehicle speed (V) is lower than a predetermined vehicle speed threshold value (Vx) and the regenerative power is smaller than the charging allowable power, the engine output (Peng) is made larger than the vehicle running power to charge the battery, And relatively reducing the ignition retardation amount,
When the vehicle speed is higher than the vehicle speed threshold and the regenerative power is larger than the charge allowable power, the engine output is made smaller than the vehicle running power to discharge the battery, and the ignition delay amount is The hybrid vehicle control device according to claim 3, wherein the hybrid vehicle control device is made larger.   The exhaust heat energy is obtained as an integrated value of the exhaust heat flow (Qexh) calculated based on the exhaust heat efficiency (ηexh) that rises as the ignition retardation amount increases and the injected fuel heat flow (Qinj). The hybrid vehicle control device according to claim 3 or 4, characterized in that:   The hybrid vehicle control according to any one of claims 1 to 4, wherein the exhaust heat energy is obtained as an integrated value of an exhaust heat flow (Qexh) calculated based on an exhaust temperature and an exhaust flow rate. apparatus.

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