JP5664456B2 - vehicle - Google Patents

Description

  The present invention relates to a vehicle including an internal combustion engine, an electric motor capable of generating electric power using at least a part of power from the internal combustion engine, and a power storage device capable of exchanging electric power with the electric motor.

  Conventionally, as an input / output control device for a secondary battery for a hybrid vehicle, an input / output possible power is calculated by using a secondary battery charge rate (SOC) and a preset SOC-input / output possible power correlation. A battery that controls input / output of a secondary battery based on the input / output available power is known (see, for example, Patent Document 1). In this input / output control device, when the secondary battery is in the input state (charged state) after the secondary battery is charged and discharged with a large current, the larger the charging rate (SOC), the larger the positive value. In addition, when the secondary battery is in the output state (discharge state), the battery state transition coefficient set so as to take a smaller negative value as the charging rate (SOC) becomes smaller is integrated, and the absolute value of the integrated value Is used as an index that quantitatively represents the change in the battery state of the secondary battery caused by the large current input / output. When it is determined that the index is equal to or greater than a predetermined value, the input possible power is corrected to be smaller as the charging rate (SOC) is larger, and the output possible power is smaller as the charging rate (SOC) is smaller. It is corrected so as to become smaller. As a result, the internal resistance of the secondary battery changes due to the continuous charging or discharging after the secondary battery is charged and discharged with a large current, and the secondary battery is charged due to the change in the internal resistance. Even if the correlation between the rate (SOC) and the input / output power is changed from the above-described predetermined SOC-input / output possible power correlation, the secondary battery can be input / output so as to correspond to the actual change of the correlation. Power is corrected. Therefore, even if the secondary battery is continuously charged at a relatively high current value, charging and discharging can be stabilized while suppressing deterioration of the secondary battery.

JP 2005-160184 A

  As described above, when the input power is limited based on the value of the index when the secondary battery is to be charged, charging is performed within the range of the limited input power. However, if charging is continued within the range of input power that is limited in this way, the above index (the absolute value of the integrated value) does not decrease, and the input power limit becomes more difficult to be released. Therefore, the limited charging is further continued. As described above, it is not preferable to suppress the deterioration of the secondary battery even though the charging of the secondary battery is limited, and the charging of the secondary battery is continuously limited. During this time, for example, the electric power regenerated by the electric motor cannot be effectively used, and the energy efficiency may be deteriorated. On the other hand, in order to prevent the input power from being restricted, it is conceivable to appropriately switch between charging and discharging of the secondary battery. However, if the charging / discharging power of the secondary battery is changed frequently, it is required for the entire vehicle. Therefore, the NV characteristic may be deteriorated due to fluctuations in engine sound.

  In view of the above, the main object of the present invention is to suppress deterioration of a power storage device due to continuous charging and improve energy efficiency while maintaining a good NV characteristic of a vehicle.

  The vehicle of the present invention employs the following means in order to achieve the main object described above.

The vehicle of the present invention
An internal combustion engine, an electric motor capable of generating electric power using at least part of the power from the internal combustion engine, an electric storage device capable of exchanging electric power with the electric motor, and a target charge of the electric storage device based on a charging rate of the electric storage device Target charge / discharge power setting means for setting discharge power, allowable charge power setting means for setting allowable charge power of the power storage device based on the state of the power storage device, and the power storage device based on the target charge / discharge power In a vehicle comprising a control means for controlling the internal combustion engine and the electric motor so as to be charged / discharged within a range of the allowable charging power,
Allowable charging power limiting means for limiting the allowable charging power set by the allowable charging power setting means as charging power as charging of the power storage device continues, and
When the allowable charging power is limited by the allowable charging power limiting means and the charging duration of the power storage device is equal to or greater than a determination threshold, at least the power storage device is charged until a predetermined release condition is satisfied. A target charge / discharge power correcting means for correcting the target charge / discharge power so as to be stopped,
The determination threshold is set shorter when the vehicle speed is included in a predetermined high vehicle speed range than when the vehicle speed is included in a low vehicle speed range lower than the high vehicle speed range.

  In this vehicle, as the charging of the power storage device continues, the allowable charging power is limited as charging power by the allowable charging power limiting means. Further, when the allowable charging power is limited by the allowable charging power limiting means and the charging duration time of the power storage device exceeds the determination threshold, charging of the power storage device is stopped at least until a predetermined release condition is satisfied. Thus, the target charge / discharge power is corrected. The determination threshold is set shorter when the vehicle speed is included in a predetermined high vehicle speed range than when the vehicle speed is included in a low vehicle speed range lower than the high vehicle speed range. As a result, in high vehicle speed regions where changes in the operating sound of the internal combustion engine in response to fluctuations in the target charge / discharge power are difficult to manifest, the NV characteristic is reduced by shortening the determination threshold and interrupting the continuation of charging of the power storage device early. While maintaining good, the limit of allowable charging power, that is, charging of the power storage device, can be released as quickly as possible. Also, in a low vehicle speed range where changes in the operating sound of the internal combustion engine in response to fluctuations in the target charge / discharge power are likely to become obvious, the target charge / discharge power can be increased by increasing the determination threshold within a range where deterioration of the power storage device can be suppressed. It is possible to maintain the NV characteristic satisfactorily by suppressing the change of the operation sound of the internal combustion engine in accordance with the fluctuation of. Therefore, in this vehicle, it is possible to suppress deterioration of the power storage device due to continuous charging and improve energy efficiency while maintaining good NV performance.

1 is a schematic configuration diagram of a hybrid vehicle 20 that is a vehicle according to an embodiment of the present invention. It is a time chart which illustrates a mode that charging / discharging electric power of battery 50 and input restriction Win change with restrictions of input restriction Win. It is a flowchart which shows an example of the charging / discharging request | requirement power setting routine performed by battery ECU52 of an Example. It is explanatory drawing which illustrates the 1st threshold value setting map for heating non-execution time and heating execution time. It is a time chart which shows an example of a mode that the charging / discharging electric power of the battery 50 and the input limitation Win change by correction | amendment of charging / discharging request | requirement power Pb *. It is a time chart which shows the other example of a mode that the charging / discharging electric power of the battery 50 and the input limitation Win change by correction | amendment of charging / discharging request | requirement power Pb *.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 that is a vehicle according to an embodiment of the present invention. A hybrid vehicle 20 shown in the figure includes an engine 22 that uses gasoline, light oil, or the like as fuel, an engine electronic control unit (hereinafter referred to as “engine ECU”) 24 that controls the engine 22, and an output shaft of the engine 22. A planetary gear 30 having a planetary carrier 34 connected to the crankshaft 26 via a damper 28, a motor MG1 connected to the sun gear 31 of the planetary gear 30 and capable of generating power using at least part of the power from the engine 22, and the planetary gear A reduction gear 35 connected to a ring gear shaft 32a as a drive shaft connected to the ring gear 32, a motor MG2 connected to the ring gear shaft 32a via the reduction gear 35, a gear mechanism 37 and a ring gear shaft 32a; Connected via differential gear 38 Drive wheels 39a, 39b, an inverter 41 interposed between the motor MG1 and the power line 54, an inverter 42 interposed between the motor MG2 and the power line 54, and inverters 41, 42. A motor electronic control unit (hereinafter referred to as “motor ECU”) 40 that drives and controls the motors MG1 and MG2, a battery 50 connected to the power line 54, and a battery electronic control unit that manages the battery 50 (hereinafter referred to as “motor ECU”). , And a hybrid electronic control unit (hereinafter referred to as “hybrid ECU”) 70 that controls the entire vehicle while communicating with the engine ECU 24, the motor ECU 40, and the battery ECU 52.

  The battery 50 is configured as a lithium ion secondary battery in the embodiment. Further, the battery ECU 52 is provided with a signal necessary for managing the battery 50, for example, a battery temperature Tb from a temperature sensor (not shown) attached to the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current Ib (hereinafter, the discharging current from the battery 50 indicates a positive value and the charging current of the battery 50 indicates a negative value) is input from a current sensor (not shown). Further, the battery ECU 52 outputs data related to the state of the battery 50 to the hybrid ECU 70 and the engine ECU 24 by communication as necessary. Further, in order to manage the battery 50, the battery ECU 52 calculates the remaining capacity (charging ratio) SOC based on the integrated value of the charging / discharging current Ib detected by the current sensor, and calculates the remaining capacity SOC and the battery temperature Tb. Based on the above, an input limit Win (negative value in the embodiment) as the charge allowable power of the battery 50 and an output limit Wout (positive value in the embodiment) as the discharge allowable power of the battery 50 are calculated. For the input / output limits Win and Wout of the battery 50, basic values of the input / output limits Win and Wout are set based on the battery temperature Tb, and the set basic value is multiplied by a correction coefficient based on the remaining capacity (SOC) of the battery 50. Can be set.

  Furthermore, battery ECU 52 sets charge / discharge required power Pb * of battery 50 based on remaining capacity SOC. In the embodiment, the relationship between the remaining capacity SOC and the charge / discharge required power Pb * is predetermined as a charge / discharge required power setting map and stored in a ROM (not shown) of the battery ECU 52. The battery ECU 52 stores the remaining capacity SOC in the remaining capacity SOC. The corresponding charge / discharge required power Pb * is derived from the charge / discharge required power setting map and set. The charge / discharge required power setting map is, for example, the charge / discharge required power Pb * so that the battery 50 is charged when the remaining capacity SOC of the battery 50 is smaller than a predetermined control center (target charge ratio) SOC *. Is set to a negative constant value Pc, and when the remaining capacity SOC is larger than the control center SOC *, the charge / discharge required power Pb * is set to a positive constant value Pd so that the battery 50 is discharged. It is done.

  When the ignition switch 80 is turned on in the hybrid vehicle 20 configured as described above, the hybrid ECU 70 detects the accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, and the vehicle speed sensor 88. The required torque Tr * is set based on the vehicle speed V, and the required power Pe * required for the engine 22 is set based on the set required torque Tr * and the charge / discharge required power Pb * of the battery 50. The hybrid ECU 70 sets the target rotational speed Ne * and the target torque Te * of the engine 22 based on the required power Pe *, and within the range of the input limit Win and the output limit Wout based on the target torque Te * and the like. Torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are set so that a torque corresponding to the required torque Tr * is obtained, and the set command values are transmitted to the engine ECU 24 and the motor ECU 40. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * from the hybrid ECU 70 receives the amount of intake air in the engine 22 so that the engine 22 is operated at the operating point consisting of the target rotational speed Ne * and the target torque Te *. Control such as adjustment control, fuel injection control, and ignition control is performed. The motor ECU 40 that receives the torque commands Tm1 * and Tm2 * performs switching control of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. As a result, the engine 22 and the motors MG1, MG2 are charged / discharged based on the charge / discharge required power Pb * within the range of the input limit Win and the output limit Wout, and the torque corresponding to the required torque Tr * is obtained. To be controlled.

  Here, a power storage device such as a lithium ion secondary battery tends to deteriorate when continuously charged with a large current, and particularly deteriorates as the charging current value (absolute value) increases and the charging time increases. Have a tendency to For this reason, in the hybrid vehicle 20 of the embodiment, in order to suppress the deterioration of the battery 50, the charging of the battery 50 is limited when it is charged with a relatively large charging current or continuously charged for a relatively long time. Thus, the value of the input limit Win based on the battery temperature Tb and the remaining capacity SOC is limited (corrected) by the battery ECU 52. Specifically, the battery ECU 52 of the embodiment calculates a limit value Winlim for the input limit Win set based on the battery temperature Tb and the remaining capacity SOC at predetermined time intervals according to the following equation (1). Then, according to the following equation (2), the battery ECU 52 has a smaller one of the larger one of the input limit Win and the limit value Winlim, and a negative value relatively close to a predetermined value 0 or a limit value Winref that is 0. Is set (reset) as the final input restriction Win. Hereinafter, the input restriction Win that is set based on the battery temperature Tb and the remaining capacity SOC and is corrected according to the above equation (2) is appropriately referred to as “pre-restriction input restriction Winb”.

Winlim = previous Winlim-k1, Ib-k2, (Ib-Ibref) (1)
Win = min (Winref, max (Win, Winlim)) (2)

  The first term on the right side in the above equation (1) is the latest limit value Winlim calculated last time, and a negative value having a relatively large absolute value set in advance as an initial value is used. Further, the second term on the right side in the equation (1) is obtained by multiplying the charge / discharge current Ib detected by the current sensor by a predetermined coefficient k1. Further, the third term on the right side of the equation (1) is preliminarily set as a charge / discharge current Ib detected by the current sensor and a negative value that does not cause deterioration of the battery 50 even if the battery 50 is continuously charged. It is obtained by multiplying the difference from the determined reference current value Ibref (negative value) by the coefficient k2. Therefore, the limit value Winlim increases toward the positive side (absolute value decreases) as the battery 50 is charged with a large current (the charge / discharge current Ib increases toward the negative side), and the battery 50 continues to be charged for a long time. The larger it is, the larger it is on the positive side. Further, the limit value Winlim increases toward the negative side (absolute value increases) as the battery 50 is discharged with a large current (the charge / discharge current Ib increases toward the positive side), and discharge of the battery 50 continues for a long time. The larger it is, the larger the negative side.

  Then, the input limit Win based on the battery temperature Tb and the remaining capacity SOC (pre-limit input limit Winb) is limited (corrected) according to the equation (2), so that when the variation range of the limit value Winlim is small, the pre-limit input limit Winb Is set as the final input restriction Win as it is. Further, when the battery 50 is charged with a large current or continuously charged for a long time, the value of the limit value Winlim increases on the positive side (the absolute value decreases), and the input is based on the battery temperature Tb and the remaining capacity SOC. When larger than the limit Win, the smaller one of the limit value Winlim and the limit value Winref (the one with a larger absolute value) is set as the final input limit Win.

  Thereby, as indicated by a broken line in FIG. 2, the final input limit Win is limited to a limit value Winref which is a predetermined threshold value on the charging side, and the battery 50 is charged with a large current or continues for a long time. The more the battery is charged, the smaller the charging power is limited. That is, when the limit value Winlim becomes larger than the input limit Win (pre-limit input limit Winb) based on the battery temperature Tb and the remaining capacity SOC, the limit of the input limit Win is started, and the limit value Winlim reaches the limit value Winref. The limit value Winlim is set as the final input limit Win, and when the limit value Winlim becomes larger than the limit value Winref, the limit value Winref is set as the final input limit Win. The limit value Winlim changes to the negative side when the battery 50 is discharged with a large current as described above or the discharge is continued for a long time. Therefore, even if the battery 50 is charged with a large current or continuously charged for a long time, the above-described input limit Win limitation, that is, the battery 50 charging limitation is released according to the amount of discharge after charging. become.

  Further, in the hybrid vehicle 20 of the embodiment, when the charging / discharging required power Pb * is set to a negative value and charging of the battery 50 is requested, the range of the input limit Win of the battery 50 set as described above. In other words, the motors MG1 and MG2 are controlled so that the battery 50 is charged with electric power larger than the input limit Win (absolute value is small). Therefore, for example, when the charging of the battery 50 is continued, the input limit Win of the battery 50 starts to be limited by the limit value Winlim (time t10 in FIG. 2), and the limit value Winlim is set as the final input limit Win. Then, the power (charging power) applied to the battery 50 starts to be limited by the input limit Win (time t20 in FIG. 2). When the limit value Winref starts to be set as the final input limit Win due to the limit value Winlim becoming larger than the limit value Winref (time t30 in FIG. 2), charging of the battery 50 is requested thereafter. If so, charging of the battery 50 with electric power equal to or higher than the limit value Winref is continued.

  However, if the charging of the battery 50 with relatively small electric power equal to or greater than the limit value Winref is continued, the limit value Winlim further increases to the positive side, and therefore the limit value Winref is set as the input limit Win. Thus, the charging with the limited charging power, that is, the limitation of the charging of the battery 50 is not easily released. In addition, it is not preferable in order to suppress the deterioration of the battery 50 that the charging is continued even though the charging of the battery 50 is restricted. Further, while the charging limitation of the battery 50 is continued, there is a possibility that the electric power regenerated by the motor MG2 cannot be effectively used and the energy efficiency is deteriorated. For this reason, in the hybrid vehicle 20 of the embodiment, the battery 50 is charged and discharged more appropriately, thereby suppressing the deterioration of the battery 50 and canceling the continuation of the restriction of the input restriction Win to improve the energy efficiency. The battery ECU 52 appropriately corrects the charge / discharge required power Pb * of the battery 50 set based on the capacity SOC.

  FIG. 3 is a flowchart illustrating an example of a charge / discharge required power setting routine that is repeatedly executed by the battery ECU 52 at predetermined time intervals in order to set the charge / discharge required power Pb *. At the start of the charge / discharge required power setting routine shown in the figure, the battery ECU 52 determines the vehicle speed V, the battery temperature Tb of the battery 50, the remaining capacity SOC, the charge duration time t1, the pre-restriction input limit Winb (the above equation (2)). Data necessary for the setting and correction of the charge / discharge required power Pb * such as the value before the correction), the input limit Win (set according to the above equation (2)), and the value of the heating flag Fh are input (step S100). ). The vehicle speed V may be directly input from the vehicle speed sensor 88 or may be input from the hybrid ECU 70 through communication. The charging duration time t1 is measured by a t1 timer (not shown) while the battery 50 is being charged, that is, from when charging of the battery 50 is started to when it is stopped. Further, the heating flag Fh is set to a value of 0 when the vehicle interior (not shown) is not heated and is heated by the electronic controller for air conditioning (not shown) that controls the air conditioner (not shown). The value is sometimes set to 1 and is input from the air conditioning electronic control unit by communication.

  After the data input process of step S100, the battery ECU 52 derives and sets the charge / discharge required power Pb * corresponding to the remaining capacity SOC from the above-described charge / discharge required power setting map (step S110). Next, the battery ECU 52 determines whether or not the vehicle interior is heated based on the value of the heating flag Fh (step S120), and then determines the charging duration threshold (determination threshold) tref1 and the charging according to the determination result. A time limit threshold (second determination threshold) tref2 is set (steps S130 and S140). That is, when the vehicle interior is not heated, the battery ECU 52 derives the charging duration threshold value tref1 corresponding to the vehicle speed V and the battery temperature Tb input in step S100 from the first threshold setting map for when heating is not performed. In addition to the setting, the charging limit time threshold value tref2 corresponding to the vehicle speed V and the remaining capacity SOC input in step S100 is derived and set from the second threshold setting map for when heating is not performed (step S130). When the vehicle interior is being heated, the battery ECU 52 derives and sets the charging duration threshold value tref1 corresponding to the vehicle speed V and the battery temperature Tb input in step S100 from the first threshold setting map for performing heating. At the same time, the charging limit time threshold value tref2 corresponding to the vehicle speed V and the remaining capacity SOC input in step S100 is derived and set from the second threshold setting map for performing heating (step S140).

  In the embodiment, the first threshold setting map for when heating is not performed and when heating is performed is, for example, when the battery temperature Tb is lower than a predetermined value, the lower the battery temperature Tb (the absolute value of the input limit Win of the battery 50). The charging duration threshold value tref1 is shortened and the charging duration threshold value tref1 in a high vehicle speed range equal to or higher than a predetermined reference vehicle speed Vref (for example, about 20 to 30 km / h) is set as illustrated in FIG. It is created in advance so as to be shorter than the charging duration threshold value tref1 in the low vehicle speed range on the lower speed side than the reference vehicle speed Vref. And the 1st threshold value setting map for the heating execution time makes the charging duration threshold value tref1 corresponding to the same vehicle speed shorter than the first threshold value setting map for the heating non-execution time as illustrated in FIG. Created in advance. In the embodiment, the charging duration threshold value tref1 is set to a time longer than the estimated time from when the limit value Winlim is the initial value until the input limit Win is limited according to the above equation (2). Further, the first threshold setting map for the heating non-execution time and the heating execution time may be created so that the charging duration threshold value tref1 is shortened as the vehicle speed V increases.

  In the embodiment, the second threshold setting map for when heating is not performed and for when heating is performed, for example, when the remaining capacity SOC is equal to or less than a predetermined value, the discharge of the battery 50 is suppressed as the remaining capacity SOC is lower. As described above, the charging limit time threshold value tref2 is shortened, and the charging limit time threshold value tref2 in the high vehicle speed range equal to or higher than the reference vehicle speed Vref (for example, about 20 to 30 km / h) is set to the charging limit in the low vehicle speed range on the lower speed side than the reference vehicle speed Vref. It is created in advance so as to be shorter than the time threshold value tref2 (see FIG. 4). Then, the second threshold setting map for heating execution is created in advance so that the charging limit time threshold tref2 corresponding to the same vehicle speed is shorter than the second threshold setting map for heating non-execution. In the embodiment, the charging limit time threshold value tref2 is set to a time longer than the expected time until the restriction of the input restriction Win according to the above equation (2) is canceled by executing the process of step S170 described later. The Further, the second threshold setting map for when heating is not performed and when heating is performed may be created so that the charging limit time threshold tref2 is shortened as the vehicle speed V increases.

  After setting the charging duration threshold value tref1 and the charging limitation time threshold value tref2 in step S130 or S140, the battery ECU 52 has the input limitation Win limited and the charging duration t1 of the battery 50 input in step S100 is the same. It is determined whether or not the charging duration threshold value tref1 set in step S130 or S140 is not less than (step S150). In step S150 of the embodiment, if the input restriction Win input in step S100 is larger than the pre-restriction input restriction Winb input in step S100 (if the absolute value is small), the input restriction Win is restricted. If the input restriction Win before restriction and the input restriction Win are the same, it is judged that the input restriction Win is not restricted. If it is determined in step S150 that the input restriction Win is restricted and the charging duration t1 of the battery 50 is equal to or longer than the charging duration threshold tref1, the battery ECU 52 sets a predetermined flag F to a value 1. At the same time, the t1 timer is reset, the t2 timer (not shown) is turned on (step S160), and the charge / discharge required power Pb * is reset to a predetermined positive value, for example, to be set in step S110. The charge / discharge required power Pb * is corrected (step S170), and this routine is temporarily terminated.

  On the other hand, when it is determined in step S150 that the input restriction Win is not restricted or the charging duration time t1 of the battery 50 is less than the charging duration threshold value tref1, the battery ECU 52 has a value of 1 for the flag F. It is determined whether or not (step S180). When the flag F is 1, the battery ECU 52 has the input restriction Win not restricted, and the time (charge limit time) t2 measured by the t2 timer is the charge restriction set in step S130 or S140. It is determined whether or not it is equal to or greater than the time threshold tref2 (step S190). When it is determined in step S190 that the input limit Win is limited or the time t2 measured by the t2 timer is less than the charge limit time threshold tref2, the battery ECU 52 determines the charge / discharge required power Pb in step S170. * Is corrected and this routine is terminated once. On the other hand, when it is determined in step S190 that the input limit Win is not limited and the time t2 measured by the t2 timer is equal to or greater than the charge limit time threshold value tref2, the battery ECU 52 sets the flag F to After setting the value to 0 and resetting the t2 timer (step S200), this routine is temporarily terminated without correcting the charge / discharge required power Pb *. Also, when it is determined in step S180 that the flag F is 0, the battery ECU 52 once ends this routine without correcting the charge / discharge required power Pb *.

  As a result of executing the charge / discharge required power setting routine as described above, the battery 50 is continuously charged with a large current, so that the input limit Win is limited according to the above equation (2) as shown in FIG. When the charging duration t1 of the battery 50 becomes equal to or longer than the charging duration threshold value tref1 (step S150), the charge / discharge required power Pb * is temporarily set to a charge side value (negative value) based on the remaining capacity SOC. Even if this is done (step S110), the charge / discharge required power Pb * is reset (corrected) to a value on the discharge side (positive value) (step S170). Then, the charge / discharge required power Pb * is corrected in such a manner that the restriction on the input restriction Win is released in step S190 and the time (charge restriction time) t2 measured by the t2 timer is equal to or greater than the charge restriction time threshold tref2. It is executed until it is determined that it has become. Thereby, in the hybrid vehicle 20 of the embodiment, even if the input restriction Win is restricted according to the above equation (2) due to the battery 50 being continuously charged with a large current, as shown in FIG. The input restriction Win can be released by stopping the battery 50 and discharging the battery 50.

  Here, when the vehicle speed V is included in the above-mentioned low vehicle speed range and the vehicle interior is not heated, the traveling sound is relatively low and there is no operation sound of the air conditioner (blower). Changes in the operating sound of the engine 22 in response to fluctuations in the power Pb * are likely to be manifested. Therefore, when the vehicle speed V is included in the low vehicle speed range and the vehicle interior is not heated, the charging duration threshold value tref1 and the charging time limit threshold value are set within the range in which the deterioration of the battery 50 can be suppressed as in the above embodiment. By making tref2 relatively long, it is possible to prevent the required power Pe * for the engine 22 from greatly fluctuating in a short cycle by correcting the required charge / discharge power Pb *. Thus, when the vehicle speed V is included in the low vehicle speed range and the vehicle interior is not heated, the input charging Win in which the actual charging power of the battery 50 is limited according to the above equation (2) as shown in FIG. However, it is possible to maintain the NV characteristics satisfactorily by suppressing the change in the operating sound of the engine 22 according to the fluctuation of the charge / discharge required power Pb *.

  On the other hand, when the vehicle speed V is included in the above-described high vehicle speed range, the charging duration threshold value tref1 and the charging limit time threshold value tref2 are set shorter than when the vehicle speed V is included in the low vehicle speed range. (Step S130 or S140). As a result, in a high vehicle speed range where changes in the operating sound of the engine 22 in response to fluctuations in the required charge / discharge power Pb * are difficult to manifest due to the presence of traveling noise, the charging duration threshold value tref1 is shortened to charge the battery 50. By cutting the continuation early and shortening the charging time limit threshold tref2 to shorten the charging / discharging cycle of the battery 50, it is possible to remove the restriction on the input restriction Win as quickly as possible while maintaining good NV characteristics. . Further, when the passenger compartment is heated, the charging duration threshold value tref1 and the charging limit time threshold value tref2 are set shorter than when the passenger compartment is not heated (step S140). As a result, the charging duration threshold value tref1 is shortened at the time of vehicle interior heating in which the change in the operating sound of the engine 22 according to the fluctuation of the charge / discharge required power Pb * is difficult to manifest due to the presence of the operating sound of the air conditioner (blower). By stopping the charging of the battery 50 as soon as possible and shortening the charging / discharging cycle of the battery 50 by shortening the charging limit time threshold value tref2, the limitation of the input limit Win is made as fast as possible while maintaining the NV characteristics well. Can be released.

  As described above, in the hybrid vehicle 20 according to the embodiment, the input restriction Win is limited as the charging power according to the above equation (2) as the charging of the battery 50 continues. If the input restriction Win is restricted according to the above equation (2) and the charging duration t1 of the battery 50 is equal to or longer than the charging duration threshold tref1 (step S150), the release condition is satisfied in step S190. The charging / discharging required power Pb * as the target charging / discharging power is corrected so that the charging of the battery 50 is stopped until the battery 50 is discharged (step S170). The charging duration threshold value tref1 as the determination threshold is set to be shorter when the vehicle speed V is included in the high vehicle speed range than when the vehicle speed V is included in a low vehicle speed range lower than the high vehicle speed range. (Steps S130 and S140). As a result, in a high vehicle speed range in which changes in the operation sound of the engine 22 according to fluctuations in the charge / discharge required power Pb * are difficult to be manifested, the continuation of the charging of the battery 50 is cut off early by shortening the charging duration threshold value tref1. Thus, it is possible to remove the input restriction Win, that is, the restriction on charging of the battery 50 as quickly as possible while maintaining the NV characteristics satisfactorily. Further, in the low vehicle speed range in which the change in the operation sound of the engine 22 according to the change in the required charge / discharge power Pb * is likely to be obvious, the charging duration threshold value tref1 is increased within a range in which the deterioration of the battery 50 can be suppressed. Further, it is possible to suppress the change in the operation sound of the engine 22 in accordance with the fluctuation of the charge / discharge required power Pb * and maintain the NV characteristics well. Therefore, in the hybrid vehicle 20 of the embodiment, it is possible to suppress deterioration of the battery 50 due to continuous charging and improve energy efficiency while maintaining good NV performance.

  Note that the above equation (1) for setting the limit value Winlim is not limited to the above-described one, and, for example, a recovery term that increases in accordance with an elapsed time from when the battery 50 is stopped to when charging is restarted. May be included. In this case, when charging of the battery 50 is stopped, the limit value Winlim increases to the negative side. Therefore, the charge / discharge required power Pb * may be set to 0 in step S170 of FIG. Further, the correction procedure of the required charge / discharge power Pb * as the target charge / discharge power is not limited to the above-described one. That is, after an affirmative determination is made in step S150 described above, the charge / discharge required power Pb * may be gradually changed to a predetermined positive value or value 0 by a smoothing process, a rate process, or the like. After an affirmative determination is made in S190, the charge / discharge required power Pb * may be gradually changed to the value set in step S110 by a smoothing process, a rate process, or the like. Furthermore, the hybrid vehicle 20 of the above embodiment is a so-called two-motor type hybrid vehicle including the motor MG1 and the motor MG2 (second electric motor), but the application target of the present invention is not limited to this. . That is, the present invention relates to a so-called series-type hybrid vehicle including an engine (internal combustion engine) and a motor (electric motor) that can generate electric power using at least a part of power from the engine, an engine (internal combustion engine), and the engine. It can be applied to a so-called single-motor hybrid vehicle that includes a motor (electric motor) that can generate power using at least a part of the power from the engine and that can output driving power and regenerative braking force. Not too long.

  Here, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. That is, in the above embodiment, the engine 22 corresponds to the “internal combustion engine”, the motor MG1 corresponds to the “electric motor”, the battery 50 capable of exchanging electric power with the motor MG1 corresponds to the “power storage device”, and in step S110 The battery ECU 52 that executes the process corresponds to “target charge / discharge power setting means”, and the battery ECU 52 that sets the pre-limit input limit Winb based on the state of the battery 50 corresponds to “allowable charge power setting means”. , The hybrid ECU 70, the engine ECU 24, and the motor ECU 40 that control the engine 22 and the motors MG1, MG2 so as to be charged and discharged within the range of the input limit Win based on the charge / discharge required power Pb * correspond to “control means”. The battery ECU 52 that restricts the input restriction Win according to the above equation (2) It corresponds to the force limiting means ", battery ECU52 executing the processing in step S120~S200 correspond to the" target charge-and-discharge power correcting unit ".

  The embodiments of the present invention have been described above using the embodiments. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

  The present invention can be used in the vehicle manufacturing industry.

  20 hybrid vehicle, 22 engine, 24 engine ECU, 30 planetary gear, 40 motor ECU, 41, 42 inverter, 50 battery, 52 battery ECU, 70 hybrid ECU, MG1, MG2 motor.

Claims (1)

An internal combustion engine, an electric motor capable of generating electric power using at least part of the power from the internal combustion engine, an electric storage device capable of exchanging electric power with the electric motor, and a target charge of the electric storage device based on a charging rate of the electric storage device Target charge / discharge power setting means for setting discharge power, allowable charge power setting means for setting allowable charge power of the power storage device based on the state of the power storage device, and the power storage device based on the target charge / discharge power In a vehicle comprising a control means for controlling the internal combustion engine and the electric motor so as to be charged / discharged within a range of the allowable charging power,
Allowable charging power limiting means for limiting the allowable charging power set by the allowable charging power setting means as charging power as charging of the power storage device continues, and
When the allowable charging power is limited by the allowable charging power limiting means and the charging duration of the power storage device is equal to or greater than a determination threshold, at least the power storage device is charged until a predetermined release condition is satisfied. A target charge / discharge power correcting means for correcting the target charge / discharge power so as to be stopped,
The determination threshold is set shorter when the vehicle speed is included in a predetermined high vehicle speed range than when the vehicle speed is included in a low vehicle speed range lower than the high vehicle speed range. .

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