JP2006187046A - Hybrid vehicle controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a hybrid vehicle with low fuel consumption. <P>SOLUTION: This hybrid vehicle equipped with an engine 1, an alternator 2, a storage device 3 and a drive motor 4, it is determined whether or not SOC of the storage device 3 and a requested driving force to be supplied from the storage device 3 requested by the hybrid vehicle are feasible and, if YES, present operation efficiency is maintained or first operation efficiency for increasing it is calculated. If NO, second operation efficiency to satisfy the requested driving force by electric power from the engine 1 and the alternator 2 is calculated. The first operation efficiency or the second operation efficiency is set as target operation efficiency, and the engine 1, the generator 2, the storage device 3 and driving motor 4 are controlled to satisfy the target operation efficiency. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a control device for a hybrid vehicle.

Conventionally, by detecting the amount of power stored in a power storage device and matching the amount of power stored with the driving efficiency of a hybrid vehicle, a target value for driving efficiency corresponding to the necessity of charging the power storage device is set, and the target value is realized. As described above, Patent Document 1 discloses a control device for a hybrid vehicle that effectively reduces the amount of fuel consumed during traveling by performing power generation by an internal combustion engine or the like and charge / discharge control of a power storage device.
JP 2002-171604 A

  When the hybrid vehicle travels, the driver may be required to promptly start up the driving force. In this case, electric power is supplied from the power storage device to the drive motor, and the drive force can be quickly started up as compared with the engine. Therefore, the power storage device must always store a predetermined amount of abnormal power storage so that power can be supplied from the power storage device to the drive motor in preparation for a driving force request from the driver.

  In the above invention, when the amount of power stored in the power storage device (hereinafter referred to as SOC (State Of Charge)) is associated with the driving efficiency of the hybrid vehicle, the SOC is always used in preparation for the driving force request from the driver as described above. It was necessary to maintain the amount of electricity stored above a predetermined amount (hereinafter referred to as driving force ensuring SOC). For this purpose, the lower limit value of the SOC of the power storage device is set as the driving force ensuring SOC so that the driving force request from the driver as described above can always be realized. Then, operation efficiency, for example, fuel injection control of the engine is performed so that charging is performed when the SOC of the power storage device is always lower than the lower limit value so that the SOC of the power storage device is equal to or higher than the lower limit value. As a result, the SOC of the power storage device does not fall below the lower limit value, so the vehicle travels while ensuring the driving force securing SOC. By the way, when the SOC of the power storage device is changing over the lower limit value, the surplus power is used to improve the driving efficiency of the vehicle. That is, when the operation efficiency of the power generation device is poor, the power storage device is discharged, and when the operation efficiency of the power generation device is good, the power storage device is charged. Alternatively, electric power generated by regenerative braking by the drive motor during deceleration of the vehicle can be stored.

  The charge / discharge control of the power storage device for improving the fuel efficiency is performed by repeating charge / discharge between the SOC lower limit value and the upper limit SOC which is a physical limit value of the power storage capacity of the power storage device. Therefore, the larger the chargeable / dischargeable capacity between the SOC lower limit value and the upper limit value, the higher the fuel efficiency improvement effect can be expected (for example, the ability to store more regenerative power greatly contributes to the fuel efficiency improvement).

  However, in order to ensure the driving force securing SOC as described above, the fuel efficiency improvement effect will be under pressure unless the capacity of the power storage device is increased.

  In view of this, it is known that the required power storage amount of the driving force ensuring SOC increases or decreases depending on the driving state of the vehicle. For example, in the case of high vehicle speeds, there is little demand for a quick rise in driving force, so the driving force securing SOC may be minimal, and conversely, in driving situations where there is a lot of acceleration / deceleration in urban areas, mountainous areas, etc. It is necessary to secure a lot. Therefore, it is conceivable to increase / decrease the driving force securing SOC in accordance with the driving situation to change the SOC lower limit value as described above to increase the chargeable / dischargeable power storage amount that can be used for fuel efficiency improvement control.

  However, even when the driving force securing SOC is increased or decreased, the chargeable / dischargeable storage capacity that can be used for improving the fuel efficiency also changes according to the increase or decrease of the driving force securing SOC, so that the target efficiency is frequently changed to improve the fuel efficiency. There was a problem that the contribution was not enough.

  The present invention was invented to solve such problems, and aims to improve the fuel efficiency of a hybrid vehicle.

  In the present invention, a power generation device that generates electric power for driving the vehicle, a drive device that drives the vehicle with electric power and generates electric power during regenerative travel of the vehicle, and the power generation device and the drive device are electrically connected. In a control device for a hybrid vehicle comprising a power storage device that stores power and supplies power to the drive device, charge state detection means for detecting the charge state of the power storage device, and power storage required for realizing the drive force request Driving force securing energy calculating means for calculating the driving force securing energy of the device, and driving force for determining whether or not the driving force request can be realized by the power supplied from the storage device based on the charging state and the driving force securing energy The first driving effect in which the operating efficiency of the power generator is maintained or increased when the driving force request can be realized by the realizability determining means and the power supplied from the power storage device. The first driving efficiency calculating means for calculating the second driving efficiency that enables the required driving force to be realized by the electric power from the power generation device when the driving force request cannot be realized by the electric power supplied from the power storage device Second operating efficiency calculation means, target operating efficiency setting means for setting the target operating efficiency to the first operating efficiency or the second operating efficiency, and the power generation device, the driving device, and the power storage device to control the target operating efficiency Control means.

  In addition, a power generation device composed of an internal combustion engine and a generator for driving the vehicle, a drive device for driving the vehicle with electric power, an electric connection between the power generation device and the drive device to store electric power, and electric power to the drive device In a control device for a hybrid vehicle that travels by transmitting a driving force from at least one of the internal combustion engine and the drive device to an output shaft, a charge state detection unit that detects a charge state of the power storage device Driving power securing energy calculating means for calculating the driving power securing energy of the power storage device necessary for realizing the driving power demand, and the power supplied from the power storage device based on the charging state and the driving power securing energy. The driving efficiency of the power generation device when the driving force request can be realized by the driving force realization feasibility determining means for determining whether or not it is feasible and the power supplied from the power storage device The required driving force can be realized by the electric power from the power generation device when the driving force request cannot be realized by the first operating efficiency calculating means for calculating the first operating efficiency maintained or increased and the electric power supplied from the power storage device. A second operating efficiency calculating means for calculating the second operating efficiency, a target operating efficiency setting means for setting the target operating efficiency to the first operating efficiency or the second operating efficiency, and a power generator so as to realize the target operating efficiency And a control means for controlling the drive device and the power storage device.

  According to the present invention, when the required driving force required for the vehicle can be realized by the electric power supplied from the power storage device, the first driving efficiency is calculated so as to maintain or increase the driving efficiency of the power generation device. When the required driving force required for the power supply device cannot be realized by the electric power supplied from the power storage device, the second driving efficiency for realizing the required driving force by the electric power from the power generation device is calculated, and the first operating efficiency or the first 2 Set the operating efficiency to the target operating efficiency. Since the power generation device, the drive device, and the power storage device are controlled so as to achieve the target operating efficiency, if the required driving force can be achieved only with the power supplied from the power storage device, for example, the fuel efficiency of the engine is maintained high. be able to.

  The configuration of the first embodiment of the present invention will be described with reference to the block diagram of FIG. This embodiment is a series hybrid vehicle.

  The series hybrid vehicle is an internal combustion engine 1 that produces an output by burning gasoline or the like as an actuator for driving the vehicle, and is directly connected to the engine 1 to convert the output of the engine 1 into electric power, and performs cranking when the vehicle is started. A generator 2, a power storage device 3 that stores electric power, and a drive motor 4 that is a drive device driven by electric power are provided (the engine 1 and the generator 2 constitute a power generation device).

  The power storage device 3 stores the electric power converted by the generator 2 and supplies the electric power to the drive motor 4. Moreover, the electric power obtained by the drive motor 4 at the time of regenerative travel is stored. As the power storage device 3, for example, a secondary battery using nickel hydride, lithium ions, or the like, or an electric double layer capacitor is used. Note that the power storage device 3 supplies power to the generator 2 when cranking is performed when the vehicle is started.

  The drive motor 4 generates torque by the electric power stored in the power storage device 3, transmits the torque to the tire 5 via the final gear 6, and causes the vehicle to travel. Further, during regenerative traveling in which the vehicle decelerates by a braking device (not shown), electric power is generated by regenerative energy, and a part of the electric power is charged to the power storage device 3.

  In this drive system, the output from the engine 1 is converted into electric power by the generator 2, and the electric power is mainly used to generate torque by the drive motor 4, and the torque is transmitted to the tire to travel. Further, the power generated excessively by the generator 2 is charged in the power storage device 3, and part of the power generated by the drive motor 4 is also charged in the power storage device 3 during regenerative travel. The power charged in the power storage device 3 is used as auxiliary power to the drive motor 4 during acceleration or the like. Also used in auxiliary machinery.

  The control system for controlling the vehicle includes an engine controller 7 that controls the output of the engine 1, a generator controller 8 that performs vector control of the rotational speed of the generator 2, that is, the electric power generated by the generator 2, and the drive motor 4. A drive motor controller 10 that performs torque vector control is provided. Further, a power storage device controller 9 that detects the voltage and current of the power storage device 3 and calculates the SOC of the power storage device 3 is provided. Further, an integrated controller 11 that issues an output command to the engine controller 7 according to the SOC of the power storage device 3 and the throttle opening of a throttle (not shown), issues a rotation command for the motor 2 to the generator controller 8, and issues a motor torque command to the drive motor controller 10. Is provided.

  Next, charge / discharge control of the power storage device 3 in the control system will be described with reference to the flowchart of FIG. In addition, this control is repeatedly calculated for every predetermined period of 10 ms, for example.

  In step S100, the state of charge of power storage device 3 is detected by a voltage sensor (not shown) and a current sensor (not shown) provided in power storage device 3. As a method for detecting the state of charge of the power storage device 3, the current I (A) flowing through the power storage device 3 is detected by a current sensor, and the SOC of the power storage device 3 is calculated by integration according to equation (1).

  Here, SOC (%) is the state of charge of the power storage device 3, and CAP (Ah) is the capacity of the power storage device 3. In addition, since there is a possibility that an error occurs in the current value detected by the current sensor, the state of charge of the power storage device 3 may be corrected by appropriately correcting the current value by a method other than integrating the current value (step) S100 constitutes a charge state detection means).

  In step S101, the required driving force requested by the driver, that is, the driving force securing SOC (driving force securing energy) of the power storage device 3 necessary for realizing acceleration is calculated (step S101 constitutes the driving force securing energy calculating means. To do).

  A case where the accelerator pedal is depressed by the driver and the vehicle is requested to accelerate will be described with reference to FIG. When the accelerator pedal is depressed as shown in FIG. 3 (a) and an acceleration request is made from the driver, the output of the engine 1 is to be increased according to the requested output (solid line in FIG. 3 (b)). However, since a response delay occurs in the output from the engine 1 (dotted line in FIG. 3B), in the hybrid vehicle, electric power is supplied from the power storage device 3 to the drive motor 4 (FIG. By indicating the discharge power), the drive motor 4 generates an output with little response delay, and responds to the driver's acceleration request. Therefore, it is necessary to store in advance the power supplied to the drive motor 4 in the power storage device 3 (the shaded area in FIG. 3C indicates the power required for the acceleration request).

  Next, the driving force securing SOC necessary for satisfying the driver acceleration request will be described with reference to FIG. The driving force securing SOC required to satisfy the driver's acceleration request is determined by the traveling state of the vehicle, for example, the vehicle speed. When the vehicle speed is high, there is a high possibility that the accelerator opening is already deeply depressed, and the driving force securing SOC for the driver's acceleration request becomes small. In addition, when the vehicle speed is low, there is a high possibility that the accelerator opening is not deeply depressed, and if the accelerator opening is deeply depressed after that, the acceleration request required for the vehicle may increase. In order to satisfy the demand, the driving force securing SOC increases. In this embodiment, the driving force securing SOC necessary for satisfying the driver's acceleration request is calculated from the map shown in FIG. 4 according to the vehicle speed. Further, the driving force securing SOC may be corrected not only by the vehicle speed but also by the gradient of the road surface.

  In step S102, the current SOC of power storage device 3 calculated in step S100 is compared with the driving force securing SOC calculated in step S101, and whether the driving force securing SOC is equal to or smaller than the SOC of power storage device 3 is determined. to decide. When the driving force securing SOC is smaller than the SOC of the power storage device 3, that is, when the required acceleration can be realized by generating torque in the drive motor 4 with the electric power stored in the power storage device 3, the first of step S103 When the driving efficiency setting control proceeds to the driving efficiency setting control and the SOC of the power storage device 3 is larger than the SOC of the power storage device 3, that is, when the drive motor 4 is caused to generate torque with the power stored in the power storage device 3 and the requested acceleration cannot be realized. Advances to the second driving efficiency setting control of step S104 (step S102 constitutes a driving force realization feasibility judging means).

  Note that in the comparison between the driving force ensuring SOC and the SOC of the power storage device 3 in step S102, hysteresis (correction means) may be provided in the comparison. Here, a comparison determination between the driving force ensuring SOC and the SOC of the power storage device 3 when hysteresis is provided will be described with reference to FIG. When hysteresis is provided, once the driving force securing SOC becomes smaller than the SOC of power storage device 3 (moves from point a to point b in FIG. 5), the SOC of power storage device 3 becomes a predetermined SOC (in FIG. 5). , C)), it is determined that the requested acceleration cannot be realized even if electric power is supplied from the power storage device 3 and torque is generated in the drive motor 4. When the SOC of the power storage device 3 reaches a predetermined SOC, it is determined that power can be supplied from the power storage device 3 to generate torque in the drive motor 4 to achieve the requested acceleration (from point c to point d in FIG. 5). Move to). As a result, in the comparison between the driving force securing SOC and the SOC of the power storage device 3, it is possible to suppress changes in the operating points of the actuators due to frequent judgment changes in the magnitude relationship between the driving force securing SOC and the SOC of the power storage device 3. , The feeling of incongruity given to the driver can be reduced.

  The driving force ensuring SOC sets a lower limit SOC corresponding to the lower limit voltage of the power storage device 3 in order to prevent overdischarge of the power storage device 3, and uses the SOC obtained by adding an SOC for realizing an acceleration request with respect to the lower limit SOC as a driving force. The secured SOC is assumed. When the engine 1 is restarted from the power storage device 3, the SOC obtained by adding the SOC necessary for restarting the engine 1 to the lower limit SOC is set as the driving force securing SOC. That is, three energy reserves are set in advance in the power storage device, the first energy for preventing overdischarge, the second energy for starting the engine, and the third energy for securing driving force. . In the present invention, the first energy and the second energy are fixed values, and the third energy is a fluctuation value as described above.

  Next, the first operation efficiency setting control in step S103 will be described with reference to the flowchart of FIG.

  In step S200, the driving efficiency when the driving force ensuring SOC is changed in S101 is calculated. The operating efficiency is the fuel consumption per generated power when the engine 1 is operated and the generator 2 generates power. The operating efficiency depends on the fuel consumption characteristics of the engine 1, the loss characteristics of the generator 2, the charge / discharge efficiency of the power storage device 3, and the like. Change.

  As for the operation efficiency, the characteristics shown in FIG. 7 can be obtained with the generated power on the horizontal axis and the operating efficiency on the vertical axis according to each driving force requirement. The line on the graph represents the power supplied to the drive motor 4 in order to realize the drive power requirement of the driver as the drive power.

  In this embodiment, when the fuel consumption characteristic of the engine is approximately 30 [kW], the power generation amount per unit fuel is the largest, that is, the fuel consumption characteristic is good.

  Here, the tendency when the drive power in FIG. 7 is 5 [kW] is that the power generation amount of the engine 1 is set to 5 [kW] when the operation is performed only by the power generated by the engine 1. In this case, the amount of power generation is too small and the fuel consumption characteristics are significantly deteriorated. Therefore, power generation by the engine 1 is stopped and power is supplied from the power storage device 3. Alternatively, when the SOC of the power storage device 3 is lowered, the engine 1 is operated at about 30 [kW] with good fuel efficiency of the engine 1 and the remaining 25 [kW] is charged in the power storage device 3. In this case, although the fuel consumption at that time deteriorates, the power stored in a state where the fuel consumption characteristics are good is slightly improved in efficiency due to charging / discharging, but the fuel consumption efficiency remains approximately good. is there. That is, in the future, it is possible to supply the electric power stored with good fuel consumption efficiency to the drive motor 4, so that it can be understood that it is possible to contribute to improving the fuel consumption in view of the entire vehicle travel. Further, for example, it is understood that it is efficient to supply 20 [kW] from the power storage device 3 and generate the remaining 30 [kW] with the engine 1 when the drive power is 50 [kW]. However, when the SOC of the power storage device 3 is low and 20 [kW] cannot be supplied, when the SOC is extremely low, all power is generated by the engine 1, and when the SOC has some margin, about 10 [kW] is supplied. It is conceivable to operate 1 at 40 [kW] to suppress the deterioration of the fuel consumption rate.

  These tendencies are shown in a form corresponding to the SOC of the power storage device 3 in FIG. That is, when the tendency of FIG. 7 is viewed from the power storage device 3 side, the operation efficiency is deteriorated when the charge amount is increased, and the operation efficiency is improved when the charge amount is decreased. That is, it can be seen that if the SOC of the power storage device 3 is sufficiently secured, it is not necessary to increase the amount of charge and good operating efficiency can be maintained. The operation efficiency is calculated from the map of FIG. 9 in which the tendency of FIG. 8 is expressed as the relationship between the SOC of the power storage device 3 and the operation efficiency. If the SOC is low, the target operating efficiency is set low and charging is promoted even if the efficiency is low. Conversely, if the SOC is high, discharging is given priority, and charging is performed only when the efficiency is high. . Thereby, it becomes possible to set the target operation efficiency according to the necessity of charge based on SOC. In the figure, the relationship between the SOC and the target operating efficiency is linear, but it may be characterized so that the fuel consumption during traveling can be effectively reduced based on the above tendency.

  From these tendencies, the driving efficiency set in S200 is that if the driving force ensuring SOC is increased, the available SOC that contributes to the determination of the driving efficiency is reduced, and the bad driving efficiency is set. On the other hand, if the driving force securing SOC is decreased, the available SOC is increased, so that a good driving efficiency can be set.

  In step S201, the current operation efficiency is compared with the operation efficiency calculated in S200. Here, the current operating efficiency is the operating efficiency set in the previous control.

  If the current operation efficiency is greater than the operation efficiency calculated in S200, that is, if the current operation efficiency is better, the process proceeds to S202.

In S202, the current operation efficiency is maintained and the process proceeds to S204. In S204, the first operation efficiency that is the target operation efficiency is set with the operation efficiency set in S202 or S203 described later as the first operation efficiency (Step S204). A target operating efficiency setting means).

  Here, S202 is a feature of the present invention. When the step of S202 is reached, it is determined in the previous determination of S102 of FIG. In S201, it is determined that the available SOC is reduced due to the change in the driving force securing SOC, and the driving efficiency is deteriorated. That is, the SOC in the case of reaching the step of S202 is equal to or greater than the driving force ensuring SOC, and indicates that the SOC is insufficient to achieve the current target operating efficiency. Originally, since it is determined in S201 that the SOC is insufficient, it is desirable to reset a new target operating efficiency corresponding to the insufficient SOC. However, the driving force securing SOC is secured in preparation for a driver's rapid accelerator operation, and there is a possibility of switching to another traveling scene without using the driving force securing SOC. The target driving efficiency is determined on the assumption of a long-term schedule, whereas the driving force ensuring SOC is a time difference resulting from being determined on the assumption of a relatively short-term schedule. In the present invention, this difference is utilized to maintain the target operating efficiency.

On the other hand, if the relationship between the driving efficiency calculated in S200 in S201 and the current driving efficiency is better in S200, the process proceeds to S203. In S203 and S204, the driving efficiency calculated in S200 is newly set. Set as 1 operating efficiency. In this way, the process proceeds to S203, unlike the case of S202 described above, when the driving efficiency changes in a favorable direction, that is, when the SOC that can be used for fuel efficiency improvement control is increasing. In such a case, since the driving efficiency is improved by changing the driving efficiency, it is expected that the fuel efficiency is improved by setting the driving efficiency calculated in S200 (steps S200 to S203 constitute the first driving efficiency calculating means. ).

  On the other hand, if the driving force ensuring SOC is larger than the SOC of power storage device 3 in step S102, the process proceeds to step S104. Next, the second operation efficiency setting control in step S104 will be described using the flowchart of FIG.

  In step S300, the current power consumption of the drive motor 4 is calculated, and the driving efficiency ηd during direct travel, which is the driving efficiency when the power consumed by the drive motor 4 is generated by the generator 2, is calculated. The driving efficiency ηd during direct travel is set by power consumption, fuel consumption characteristics of the engine 1, loss characteristics of the generator 2, etc. (Step S300 constitutes drive motor power consumption calculation means and direct travel operation efficiency calculation means. ).

In step S301, a deviation between the driving force securing SOC calculated in step S300 and the current SOC of the power storage device 3 is calculated, and from the direct driving operation efficiency ηd calculated in step S104,
η = ηd + K × (SOCd−SOC) Formula (2)
To calculate and set the operation efficiency (hereinafter referred to as second operation efficiency) η as the target operation efficiency. Here, K is a specified value (where K is determined as an allowable deterioration in operating efficiency), and SOCd is a driving force securing SOC (steps S300 and S301 are second operating efficiency setting means, target Constitutes operating efficiency setting means).

  When the deviation between the driving force securing SOC and the SOC of the power storage device 3 is large, the second operating efficiency η increases, that is, the second operating efficiency η decreases, and the driving power securing SOC and the SOC of the power storage device 3 are reduced. Is small, the second operating efficiency η decreases, that is, the second operating efficiency η increases. Thereby, when the deviation between the driving force ensuring SOC and the SOC of power storage device 3 is large, the SOC of power storage device 3 can be quickly increased. Further, when the deviation between the driving force ensuring SOC and the SOC of power storage device 3 is small, the second operating efficiency can be increased and the SOC of power storage device 3 can be increased.

  With the above control, when the driving force ensuring SOC is larger than the SOC of the power storage device 3, the second operation efficiency is set so as to promote the charging of the power storage device 3. Thereby, the SOC of power storage device 3 can be increased, and rapid acceleration can be realized.

  In step S105, target generated power that achieves the target operating efficiency is set from the map shown in FIG. 11 from the target operating efficiency that is the first operating efficiency calculated in step S103 or the second operating efficiency calculated in step S104. For example, assuming that the target operating efficiency is the broken line in FIG. 9 and the driving power is 20 kW, the target generated power by the generator 2 is a in the figure. Here, when the target generated power is larger than the drive power, a charging mode for charging the power storage device 3 from the engine 1, and when the target generated power is smaller than the drive power, the engine 1 is operated, and further the power storage device Assist mode in which discharge is performed from 3 and torque is generated by the drive motor 4. Direct mode in which the drive power is equal to the target generated power, and the power generated by the generator 2 by operating the engine 1 is directly used by the drive motor 4. If there is no generated power that realizes the EV mode, the EV mode discharges only from the power storage device 3, and each travel mode is determined according to the drive motor 4 and the generated power. Note that details regarding the selection of the operation mode include a method described in Japanese Patent Application Laid-Open No. 2002-171604, which is a conventional example. In addition, in FIG. 9, when there are a plurality of generated powers that achieve the target operating efficiency, the larger generated power is selected as the target generated power.

  In step S106, each actuator operating point with the smallest fuel consumption by the engine 1 is calculated based on the target generated power set in step S105. In the calculation, the operating point of the engine 1 corresponding to the generated power as shown in FIG. 14 is uniquely obtained using the efficiency characteristic of the generator 2 shown in FIG. 12 and the fuel consumption characteristic of the engine 1 shown in FIG. it can. Although the operating point of the engine 1 is shown in FIG. 14, the operating point of the corresponding generator 2 can also be calculated based on the figure.

  In step S107, charge / discharge control is performed to achieve the target operating point of each actuator. In charge / discharge control, the engine 1 and the generator 2 are controlled so as to realize the obtained operating point, and the drive motor 4 is controlled so as to satisfy the driver's required driving force.

  When the SOC of the power storage device 3 is larger than the driving force ensuring SOC by the above control, the first operating efficiency having a high operating efficiency is set, and the SOC of the power storage device 3 is smaller than the driving force ensuring SOC. Sets the second operating efficiency for promoting the charging of the power storage device 3 and controls the engine 1 to improve the fuel efficiency of the engine 1 and the power storage device when the SOC of the power storage device 3 is small 3 can be increased.

  Next, the effect of the first embodiment of the present invention will be described.

  In this embodiment, the driving force ensuring SOC required for supplying the required driving force required for the hybrid vehicle from the power storage device 3 is compared with the current SOC of the power storage device 3, and the power storage device is more than the driving force ensuring SOC. When the SOC of 3 is large, the current operation efficiency is maintained or the first operation efficiency that is higher than the current operation efficiency is set, and the SOC of the power storage device 3 is smaller than the driving force securing SOC In this case, the second operation efficiency is set such that the amount of charge to the power storage device 3 is larger than the first operation efficiency. Then, the engine 1, the generator 2, the power storage device 3, and the drive motor 4 are controlled based on the first operation efficiency and the second operation efficiency. Accordingly, when the SOC of the power storage device 3 is larger than the SOC for securing the driving force, the fuel efficiency of the engine 1 can be improved by operating the engine 1 with the first driving efficiency having a relatively high driving efficiency. . Further, when the SOC of the power storage device 3 is smaller than the SOC for securing the driving force, the SOC of the power storage device 3 is increased by operating the engine 1 with the second operating efficiency that promotes charging of the power storage device 3. Therefore, when electric power is required from the power storage device 3, power can be supplied from the power storage device 3, the output of the engine 1 can be reduced or stabilized, and the fuel consumption of the engine 1 can be improved.

  When the first driving efficiency is set, the current driving efficiency is compared with a predetermined driving efficiency at which the fuel efficiency of the engine 1 set in advance is good. When the current driving efficiency is higher than the predetermined driving efficiency, By maintaining the current driving efficiency, the fuel consumption of the engine 1 can be stabilized, and the fuel consumption of the engine 1 can be improved.

  Further, when the current operation efficiency is lower than the predetermined operation efficiency, the operation efficiency is calculated from the SOC of the power storage device 3, and when the calculated operation efficiency is higher than the current operation efficiency, the calculated operation efficiency is calculated. If the calculated driving efficiency is lower than the current driving efficiency, the current driving efficiency is maintained, so that the driving efficiency of the engine 1 is changed or maintained so that the fuel efficiency of the engine is improved. can do.

  When setting the second driving efficiency, the power consumption of the drive motor 4 is calculated, and the driving efficiency ηd during direct travel, which is the driving efficiency when the power consumed by the drive motor 4 is generated by the generator 2, is calculated. . When the deviation between the driving force SOC and the SOC of the power storage device 3 is large with respect to the driving efficiency during direct travel ηd, the direct travel operation efficiency ηd that increases the amount of charge to the power storage device 3 is corrected, Set the operation efficiency of 2. Accordingly, the amount of power generated by the engine 1, that is, the generator 2, is increased in accordance with the SOC of the power storage device 3, and the SOC of the power storage device 3 is increased. For example, the first fuel efficiency of the engine 1 is good at the next control. It becomes easy to shift to driving efficiency, and the fuel consumption of the engine 1 can be improved.

  When the first driving efficiency or the second driving efficiency is set by comparing the driving force securing SOC with the SOC of the power storage device 3, by providing hysteresis, the driving power securing SOC and the SOC of the power storage device 3 It is possible to prevent frequent changes in the comparison determination, and it is possible to suppress changes in the operating points of the n actuators such as the engine 1. This can reduce the uncomfortable feeling felt by the driver.

  Next, a second embodiment of the present invention will be described using the schematic configuration diagram of FIG. This embodiment is a parallel hybrid vehicle.

  The parallel hybrid vehicle is an engine 31 that is an internal combustion engine that generates an output by burning gasoline or the like as an actuator for driving the vehicle, a transmission 34 that changes a rotation speed and a rotation radius of an output shaft of the engine 31, and a transmission. A speed reduction device 35 that further reduces the rotational speed of the motor 34, a motor 33 that is the same as or independently of the engine 1 and powers the vehicle, and a power storage device 42 that supplies electric power to the motor 33 and stores regenerative energy during vehicle deceleration. Prepare.

  The engine 31 and the motor 33 can be connected by the clutch 32, that is, the traveling of the vehicle by the clutch 32 is switched between traveling by the power of the engine 31 and the motor 33 and traveling by the power of the motor 33 alone. Torque generated by the engine 31 and the motor 33 is decelerated by the reduction gear 35 and transmitted to the tire 37 via the final gear 36 so that the vehicle travels.

  The clutch 32 is a powder clutch and can adjust the transmission torque. A dry single plate clutch or a wet multi-plate clutch may be used.

  The transmission 34 is a continuously variable transmission, and is supplied with pressure oil from a hydraulic device 38. When a belt type continuously variable transmission is used, the belt and the clamp are lubricated. An oil pump (not shown) that supplies the pressure oil of the hydraulic device 38 is driven by a motor 39. The transmission 34 may be a toroidal continuously variable transmission in addition to the belt type, a transmission that changes in stages, or a transmission that uses planetary gears. In a transmission using a planetary gear, for example, the output shaft of the engine 31 is coupled to the carrier, the output shaft of the motor 33 is coupled to the sun gear, and the ring gear is coupled to the reduction gear 35. Thus, by changing the rotation speed of the sun gear, it is possible to change the rotation speed of the carrier and the ring gear steplessly, and at this time, it is possible to create a state in which the driving force of the engine 31 is not transmitted to the reduction gear 35. Therefore, the clutch 32 need not be provided.

  The motor 33 and the motor 39 are AC electric motors, and an inverter 40 is provided between the motor 33 and the power storage device 42, and an inverter 41 is provided between the motor 39 and the power storage device 42. The inverters 40 and 41 convert the power charged from the motor 33 to the power storage device 42 from AC to DC, and the power supplied from the power storage device 42 to the motors 33 and 39 is converted from DC to AC. The motors 33 and 39 may use DC motors, and in that case, DC-DC converters are used instead of the inverters 40 and 41.

  The power storage device 42 uses a secondary battery such as a lithium-ion battery, a nickel-hydrogen battery, or a lead battery, or an electric double layer capacitor.

  An integrated controller 44 that controls the output of the engine 31 and the like is also provided.

  Since the charge / discharge control of the power storage device 3 of this embodiment is the same as the control of the first embodiment, description thereof will be omitted, but the motor 33 is controlled instead of the drive motor 4 of the first embodiment. To do. The driving efficiency is set in consideration of the gear ratio by the transmission 34 and the like.

  In addition, the driving efficiency ηd at the time of direct traveling in step S300 in the first embodiment is the driving efficiency when the required driving force is realized by the engine 31.

  With the above configuration, the same effect as that of the first embodiment can be obtained.

  Next, a third embodiment of the present invention will be described using the schematic configuration diagram of FIG. This embodiment is a fuel cell vehicle.

  The fuel cell vehicle includes a fuel cell 51 that generates power using raw materials supplied from an oxidant supply device (not shown) as well as a hydrogen supply device (not shown), a fuel cell controller 52 that controls the power generated by the fuel cell 51, and an integrated controller 53. Is provided. In addition, although the polymer electrolyte fuel cell is used for the fuel cell 51, various types of fuel cells such as phosphoric acid and molten carbonate type may be used. The hydrogen supply device may be a hydrogen cylinder or a device provided with a reformer. About another structure, it is the same as the case where the engine 1 and the generator 2 are used.

  Since the charge / discharge control of the power storage device 3 of this embodiment is the same as the control of the first embodiment, description thereof is omitted here, but the fuel cell 51 is controlled instead of the engine 1 of the first embodiment. To do.

  Also in this embodiment, the same effect as the first embodiment can be obtained.

  It goes without saying that the present invention is not limited to the above-described embodiments, and includes various modifications and improvements that can be made within the scope of the technical idea.

  The present invention can be used for a hybrid vehicle using the output from the power storage device.

1 is a schematic configuration diagram of a first embodiment of the present invention. It is a flowchart which shows the charge / discharge control from the electrical storage apparatus of this invention. It is a map which shows the change of the accelerator opening at the time of the acceleration request | requirement with the vehicle of this invention. It is a map which shows the change of an output when there is an acceleration request | requirement in the vehicle of this invention. It is a map which shows the change of the electrical storage state of the electrical storage apparatus when the vehicle of this invention has an acceleration request | requirement. It is a map which shows the relationship between the vehicle speed of this invention, and driving force ensuring SOC. It is a map which shows the hysteresis at the time of comparing driving force ensuring SOC and SOC of an electrical storage apparatus in this invention. It is a flowchart which shows the 1st driving | operation efficiency setting control of this invention. It is a map which shows the driving | operation efficiency characteristic of this invention. It is a map which shows the operating efficiency of this invention, and the charge amount to an electrical storage apparatus. It is a map which calculates the driving | operation efficiency of this invention. It is a flowchart which shows the 2nd operation efficiency setting control of this invention. It is a map which shows the relationship of the target operating efficiency of this invention, target generated electric power, and drive electric power. It is a map which shows the efficiency characteristic of the generator of this invention. It is a map which shows the fuel consumption characteristic of the engine of this invention. It is a map which calculates | requires the operating point of the engine of this invention. It is a schematic block diagram of 2nd Embodiment of this invention. It is a schematic block diagram of 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Generator 3 Power storage device 4 Drive motor 11 Integrated controller

Claims (8)

A power generator for generating electric power for driving the vehicle;
A driving device for driving the vehicle with electric power and generating electric power during regenerative running of the vehicle;
In a control device for a hybrid vehicle, comprising: a power storage device that is electrically connected to the power generation device and the drive device to store power, and that supplies power to the drive device;
Charging state detecting means for detecting a charging state of the power storage device;
Driving force securing energy calculating means for calculating driving power securing energy of the power storage device necessary for realizing the driving force request;
Based on the state of charge and the energy for securing driving force, a driving force realization availability determination unit that determines whether the driving force request can be realized by electric power supplied from the power storage device;
First operating efficiency calculation means for calculating first operating efficiency for maintaining or increasing the operating efficiency of the power generation device when the driving force request can be realized by the power supplied from the power storage device;
Second operating efficiency calculating means for calculating second operating efficiency that enables the required driving force to be realized by the electric power from the power generation device when the driving force request cannot be realized by the electric power supplied from the power storage device; ,
Target operating efficiency setting means for setting target operating efficiency to the first operating efficiency or the second operating efficiency;
A control device for a hybrid vehicle, comprising: control means for controlling the power generation device, the drive device, and the power storage device so as to achieve the target driving efficiency. The first driving efficiency calculation means includes driving efficiency calculation means for calculating driving efficiency based on the state of charge,
When the driving efficiency calculated by the driving efficiency calculating means is higher than the current driving efficiency, the calculated driving efficiency is set as the first driving efficiency,
2. The hybrid vehicle according to claim 1, wherein when the driving efficiency calculated by the driving efficiency calculating unit is lower than the current driving efficiency, the current driving efficiency is set as the first driving efficiency. Control device. The second operating efficiency calculation means includes
Driving device power consumption calculating means for calculating power consumption of the driving device for realizing the driving force request;
Direct driving driving efficiency calculation means for calculating driving efficiency when the power generation device generates power necessary to supply power consumption of the driving device,
The second driving efficiency is calculated by performing correction so that the driving efficiency calculated by the driving efficiency calculation means during direct driving becomes worse as the deviation between the driving force securing energy and the charging state is larger. The hybrid vehicle control device according to 1 or 2. The driving force realization feasibility determining means compares the charge state with the driving force securing energy,
When the state of charge is larger than the driving force ensuring energy, it is determined that the required driving force can be realized by electric power supplied from the power storage device,
4. The method according to claim 1, wherein when the state of charge is smaller than the driving force ensuring energy, it is determined that the required driving force cannot be realized by electric power supplied from the power storage device. The control apparatus of the hybrid vehicle as described in one.   The driving force realization feasibility judging means stores the previous driving force realization feasibility judgment result, and when comparing the charge state and the driving force securing energy, the judgment result is changed from the previous judgment result. 5. The control apparatus for a hybrid vehicle according to claim 1, further comprising correction means for performing correction so as to be difficult.   6. The hybrid vehicle control device according to claim 1, wherein the power generation device includes an internal combustion engine and a generator.   6. The hybrid vehicle control device according to claim 1, wherein the power generation device is a fuel cell. A power generation device comprising an internal combustion engine and a generator for driving the vehicle;
A driving device for driving the vehicle with electric power;
A power storage device that is electrically connected to the power generation device and the drive device to store electric power and supplies electric power to the drive device, and has a driving force from at least one of the internal combustion engine and the drive device. In a control device for a hybrid vehicle that travels by being transmitted to an output shaft,
Charging state detecting means for detecting a charging state of the power storage device;
Driving force securing energy calculating means for calculating driving power securing energy of the power storage device necessary for realizing the driving force request;
Based on the state of charge and the energy for securing driving force, a driving force realization availability determination unit that determines whether the driving force request can be realized by electric power supplied from the power storage device;
A first operating efficiency calculating means for calculating a first operating efficiency that maintains or increases the operating efficiency of the power generator when the driving force request can be realized by the power supplied from the power storage device;
Second operating efficiency calculating means for calculating second operating efficiency that enables the required driving force to be realized by the electric power from the power generation device when the driving force request cannot be realized by the electric power supplied from the power storage device; ,
Target operating efficiency setting means for setting target operating efficiency to the first operating efficiency or the second operating efficiency;
A control device for a hybrid vehicle, comprising: control means for controlling the power generation device, the drive device, and the power storage device so as to achieve the target driving efficiency.

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