JP6558280B2 - Control system - Google Patents

Description

  The present invention is applied to a hybrid vehicle including an engine and a motor as a drive source of the vehicle, a battery that stores electric power for driving the motor, and a power generation unit that generates electric power for charging the battery. The present invention relates to a control system for controlling the state of charge of a battery.

  For example, Patent Literature 1 describes a charge control device for a hybrid vehicle that can execute efficient energy management in the hybrid vehicle. In the charge control device of Patent Literature 1, the target SOC is changed according to the travel mode desired by the driver (whether or not in the power mode) and the travel environment (uphill or downhill). Specifically, in the case of the power mode and the uphill road, the target SOC is changed to a value larger than usual. Then, engine power generation is performed, and the SOC of the battery increases. As a result, the motor-assistable SOC range is expanded for traveling uphill. On the other hand, in the power mode and the downhill road, the target SOC is changed to a value smaller than normal. As a result, the regenerative SOC range when traveling downhill is expanded.

JP 2008-279803 A

  However, the SOC of the battery is not only based on the driving mode desired by the driver and the driving environment of the vehicle, but also by taking into account other factors to control the use of more energy and driving performance. Improvements can be expected. For example, as the battery deteriorates with use, the internal resistance increases. For this reason, the SOC is unlikely to increase when the battery is charged. Therefore, by controlling the SOC in consideration of the deterioration of the battery, it becomes easy to secure energy for performing motor assist. In addition, not only on uphill or downhill roads, but when the vehicle driver depresses the accelerator pedal more strongly, or when the switch that sets the vehicle's travel mode is set to the power mode, the battery's stored power By actively using the motor to drive the motor or regenerate power with the generator, the vehicle can be driven according to the driver's acceleration request and deceleration request, and drivability can be improved. it can.

  However, when such various factors are taken into account, if the target SOC is corrected based on the respective factors, for example, the correction values for the respective correction factors are contradictory to each other, and appropriate correction can be performed as a whole. There is a fear of not being.

  The present invention has been made in view of the above-described points, and an object of the present invention is to provide a control system that can appropriately control the state of charge of a battery even when various correction factors are taken into consideration. And

In order to achieve the above object, a control system according to a first invention includes a motor (16) and an engine (18) as a vehicle drive source, a battery (10) for storing electric power for driving the motor, and a battery. And a power generation unit (14, 16) for generating electric power for charging the battery, and for controlling the state of charge of the battery,
An SOC detector (12, 30) for detecting the SOC of the battery;
Electric power discharged from the battery and electric power charged in the battery so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S500, S510) for estimating the magnitude of the acceleration / deceleration request by the driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and also estimates the driver estimated by the acceleration / deceleration request estimation unit. The magnitude of the acceleration / deceleration request is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor.
The battery can be charged from the outside,
The control unit makes a medium-term correction factor that the battery is externally charged and that the fuel of the engine has been refueled, and corrects the limit value of the SOC change amount per unit time according to the medium-term correction factor. , the amount of change in SOC detected by SOC detection unit, so that the limit value or less, by controlling the electric power to be charged in the power及beauty battery-discharged from the battery,
When the battery is externally charged, the control unit increases the SOC change amount limit value, and when the engine fuel is supplied, the SOC change amount limit value is greater than when the battery is externally charged. Is configured so as to be reduced.
The control system according to the second invention comprises a motor (16) and an engine (18) as a vehicle drive source, a battery (10) for storing electric power for driving the motor, and electric power for charging the battery. And a power generation unit (14, 16) for controlling a charging state of a battery, which is applied to a hybrid vehicle comprising:
An SOC detector (12, 30) for detecting the SOC of the battery;
Electric power discharged from the battery and electric power charged in the battery so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S510) for estimating the magnitude of the acceleration / deceleration request by the driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and also estimates the driver estimated by the acceleration / deceleration request estimation unit. The magnitude of the acceleration / deceleration request is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor.
The control unit uses the magnitude of the SOC target value as a medium-term correction factor, corrects the limit value of the SOC change amount per unit time according to the magnitude of the SOC target value, and determines the SOC value detected by the SOC detection unit. Control the power discharged from the battery and the power charged to the battery so that the amount of change is less than or equal to the limit value,
When the SOC target value is larger than the median value of the range defined by the SOC upper and lower limit values, the control unit corrects the increase-side SOC change amount limit value to be smaller than when the SOC target value is smaller. Configured as follows.
A control system according to a third aspect of the invention includes a motor (16) and an engine (18) as a vehicle drive source, a battery (10) for storing electric power for driving the motor, and electric power for charging the battery. And a power generation unit (14, 16) for controlling a charging state of a battery, which is applied to a hybrid vehicle comprising:
An SOC detector (12, 30) for detecting the SOC of the battery;
Electric power discharged from the battery and electric power charged in the battery so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S510) for estimating the magnitude of the acceleration / deceleration request by the driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and also estimates the driver estimated by the acceleration / deceleration request estimation unit. The magnitude of the acceleration / deceleration request is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor.
The control unit uses the magnitude of the SOC target value as a medium-term correction factor, corrects the limit value of the SOC change amount per unit time according to the magnitude of the SOC target value, and determines the SOC value detected by the SOC detection unit. the amount of change is such that a limit value or less, by controlling the electric power to be charged in the power及beauty battery-discharged from the battery,
When the SOC target value is smaller than the median of the range defined by the SOC upper and lower limit values, the control unit corrects so that the limit value of the decrease-side SOC change amount becomes smaller than when the SOC target value is larger. Configured as follows.
A control system according to a fourth aspect of the invention generates a motor (16) and an engine (18) as a vehicle drive source, a battery (10) for storing electric power for driving the motor, and electric power for charging the battery. And a power generation unit (14, 16) for controlling a charging state of a battery, which is applied to a hybrid vehicle comprising:
An SOC detector (12, 30) for detecting the SOC of the battery;
Electric power discharged from the battery and electric power charged in the battery so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S510) for estimating the magnitude of the acceleration / deceleration request by the driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and also estimates the driver estimated by the acceleration / deceleration request estimation unit. The magnitude of the acceleration / deceleration request is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor.
The hybrid vehicle has a function of automatically adjusting the speed so as to follow the preceding vehicle,
When the frequency of sudden acceleration exceeding a predetermined acceleration is equal to or higher than a predetermined value, in order to suppress the sudden acceleration, the limit value for the change amount of the decreasing SOC target value is corrected to be small. The

  As described above, in the control system according to the present invention, the deterioration degree of the battery is used as a long-term correction factor, and the SOC target value is corrected according to the long-term correction factor. Specifically, for example, the SOC target value is corrected so that the SOC target value is increased as the degree of deterioration progresses. On the other hand, the magnitude of the acceleration / deceleration request of the driver of the hybrid vehicle is used as a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor. For example, the SOC upper limit value is increased and / or the SOC lower limit value is decreased as the request becomes stronger according to the magnitude of the driver's acceleration request or deceleration request.

  In this way, the correction factors are classified into at least a long-term correction factor and a short-term correction factor, and the correction target based on the long-term correction factor is different from the correction target based on the short-term correction factor. Therefore, when controlling the state of charge of the battery in consideration of various factors, it is possible to appropriately control the state of charge of the battery by suppressing the conflicting correction factors.

  The reference numerals in the parentheses merely show an example of a correspondence relationship with a specific configuration in an embodiment described later in order to facilitate understanding of the present invention, and are intended to limit the scope of the present invention. Not intended.

  Further, the technical features described in the claims of the claims other than the features described above will become apparent from the description of embodiments and the accompanying drawings described later.

It is a block diagram which shows an example of the whole structure of the control system for controlling the charge condition of the battery charged / discharged by the motor generator based on embodiment. It is a flowchart including the process for controlling the SOC of a battery based on the correction process based on each correction factor, the corrected target value, etc. which are performed in hybrid ECU. It is explanatory drawing for demonstrating each correction object by a long-term correction factor, a medium-term correction factor, and a short-term correction factor. It is the flowchart which showed the detail of the correction process based on a long-term correction factor. It is a flowchart which shows the detail of the correction process based on a medium-term correction factor when a medium-term correction factor is a driving | running | working route. It is a flowchart which shows the detail of the correction | amendment process based on a medium-term correction factor when a medium-term correction factor is external charge and oil supply. It is a flowchart which shows the detail of the correction process based on a short-term correction factor when a short-term correction factor is the magnitude | size of the acceleration / deceleration request | requirement of the driver | operator of a hybrid vehicle. It is a flowchart which shows the detail of the correction process based on a short-term correction factor in case a short-term correction factor is the operating condition of an electric equipment.

  An embodiment of a control system according to the present invention will be described in detail with reference to the drawings. FIG. 1 schematically shows an example of the configuration of a control system 100 according to the present embodiment.

  As shown in FIG. 1, the control system 100 includes a battery 10 mounted on the vehicle. The battery 10 supplies electric power to a motor generator (M / G) 16 and other electric devices 22 described later. Further, when the motor generator 16 generates electric power, the battery 10 is charged with the electric power. The battery 10 is configured by connecting a large number of battery cells in series, and can output a high voltage of, for example, 200V to 300V. As the battery 10, a nickel hydride secondary battery or a lithium ion secondary battery can be used.

  When the battery 10 is charged and discharged, a charge / discharge current (battery current) flowing through the battery 10 is detected by the current sensor 12. The battery current detected by the current sensor 12 is output to the battery ECU 30.

  In FIG. 1, an engine 18 is an internal combustion engine that generates power for driving a vehicle by burning fuel such as gasoline or light oil. The power generated by the engine 18 is transmitted to drive wheels via a clutch and a transmission (not shown). In addition, part of the power generated by the engine 18 may be used for power generation by the motor generator 16.

  A motor generator 16 is provided on a drive shaft that transmits the power of the engine 18. The motor generator 16 is composed of, for example, a three-phase synchronous motor or a three-phase induction motor. The motor generator 16 functions as an electric motor that generates positive torque (driving torque) when electric power is supplied from the battery 10, and is negatively driven by the drive shaft by the engine 18 or during braking of the vehicle. It has a function as a generator that generates power while generating the torque (braking torque). By providing a clutch between motor generator 16 and engine 18, it becomes possible to drive the vehicle only with torque generated by motor generator 16.

  Inverter 14 is provided between battery 10 and motor generator 16, converts the DC power of battery 10 into AC power, and supplies the AC power to motor generator 16. Further, the inverter 14 converts AC power generated by the motor generator 16 into DC power and supplies the DC power to the battery 10. At this time, the power supplied from the battery 10 to the motor generator 16 and the power supplied from the motor generator 16 to the battery 10 are controlled by controlling the opening and closing of a plurality of switching elements constituting the inverter 14 by a motor generator ECU 34 described later. Electric power can be controlled.

  Based on the battery current detected by the current sensor 12, the battery ECU 30 calculates an SOC (State of charge: the ratio of the actual charge amount with respect to the charge amount at the time of full charge) representing the state of charge of the battery 10. For example, the battery ECU 30 integrates the charging / discharging current with the charging current of the battery 10 as a positive value and the discharging current of the battery 10 as a negative value, and calculates the current SOC of the battery 10 based on the integrated value. For this reason, the current sensor 12 and the battery ECU 30 correspond to the SOC detection unit in the claims. The SOC detection unit is not limited to the one that calculates the SOC based on the battery current detected by the current sensor 12, and for example, calculates based on a battery electrolyte specific gravity sensor, a cell voltage sensor, a battery terminal voltage sensor, or the like. It is good also as a structure.

  The hybrid (H / V) ECU 32 corresponds to a control unit in the claims. The hybrid ECU 32 calculates a driving torque necessary for driving the vehicle based on information such as the accelerator opening and the vehicle speed indicating the accelerator pedal operation amount of the driver. When the driving torque necessary for driving the vehicle is calculated, the hybrid ECU 32 further considers the actual SOC of the battery 10, that is, considers the SOC range in which the motor can be assisted. The drive torque required for the motor generator 16 and the engine 18 is determined so that the total drive torque value of the motor and the engine 18 matches the required drive torque. When the SOC of battery 10 is extremely low, only engine 18 generates drive torque, and motor generator 16 generates power using a portion of the generated power of engine 18. In some cases.

  Hybrid ECU 32 outputs the determined required drive torque as a control command for each of motor generator ECU 34 and engine ECU 36. The motor generator ECU 34 controls the opening and closing of a plurality of switching elements constituting the inverter 14 in order to realize the required drive torque for the motor generator 16. The engine ECU 36 controls the fuel injection amount, the injection timing, the ignition timing, the intake air amount of the engine 18 and the like so as to realize the required drive torque for the engine 18. When the motor generator 16 generates power, the hybrid ECU 32 outputs a negative driving torque as the required driving torque to the motor generator ECU 34.

  Further, the hybrid ECU 32 calculates a braking torque necessary for braking the vehicle based on information such as a brake depression amount indicating the operation amount of the brake pedal and a vehicle speed. When the braking torque necessary for braking the vehicle is calculated, the hybrid ECU 32 further considers the actual SOC of the battery 10, that is, considers the regenerative SOC range, and the motor generator and the hydraulic brake ( The required braking torque for the motor generator 16 and the hydraulic brake is determined so that the total braking torque value (not shown) matches the required braking torque. Hybrid ECU 32 outputs the determined required braking torque as a control command for each of motor generator ECU 34 and brake ECU (not shown). The motor generator ECU 34 controls opening and closing of a plurality of switching elements constituting the inverter 14 so as to collect electric power corresponding to the required braking torque from the motor generator 16 in order to realize the required braking torque to the motor generator 16. The brake ECU controls the hydraulic pressure supplied to the brake cylinder of each wheel in order to achieve the required braking torque for the hydraulic brake.

  The hybrid ECU 32 receives a signal from a switch for setting the vehicle driving mode (eco mode, normal mode, power mode, etc.) and determines the driving torque and braking torque in consideration of the driving mode. good. For example, it is determined that the driving torque to be generated is increased in the order of the eco mode, the normal mode, and the power mode for the same accelerator pedal depression operation. Further, it is determined that the braking torque to be generated increases in the order of the eco mode, the normal mode, and the power mode for the same brake pedal depression operation.

  In addition, the hybrid ECU 32 controls the SOC of the battery 10 to an appropriate range, so that the initial value of the SOC target value (for example, 50%) and the initial value of the SOC upper limit value that is set based on the SOC target value (for example, the target) Value + 20%: + 20% is the initial value of the upper limit value) and the initial value of the SOC lower limit value (for example, target value -20%: -20% is the initial value of the lower limit value), and further, the SOC change amount per unit time Each initial value of the limit value is stored. The hybrid ECU 32 is charged with the electric power discharged from the battery 10 and the battery 10 so that the calculated actual SOC is within a range defined by the SOC upper limit value and the SOC lower limit value and approaches the target SOC. Control power. That is, if the battery 10 falls into an overcharge state where the SOC is excessively high or an overdischarge state where the SOC is excessively low, there is a risk of performance deterioration of the battery 10. Therefore, when the actual SOC approaches the SOC upper limit value, hybrid ECU 32 creates a control command that suppresses charging of battery 10 so as not to exceed the SOC upper limit value, and outputs the control command to motor generator ECU 34. On the other hand, when the actual SOC approaches the SOC lower limit value, hybrid ECU 32 creates a control command for suppressing discharge from battery 10 and outputs it to motor generator ECU 34 so as not to fall below the SOC lower limit value.

  Furthermore, the hybrid ECU 32 is configured to be able to acquire information related to the travel route from the navigation device 20. The navigation device 20 displays the position of the vehicle on the map on the display based on the current position of the vehicle detected by a current position detection unit (not shown) and the map data, and displays the position of the vehicle when the destination is set. The travel route is set and guided. When the travel route to the destination is set, information such as the travel route, road gradient information on the travel route, the shape, position, and number of the curved road is output to the hybrid ECU 32. As will be described in detail later, the information related to the travel route is used by the hybrid ECU 32 to set a limit value for the amount of change in SOC per unit time as a medium-term correction factor when controlling the SOC of the battery 10. Is done.

  For example, the electric device 22 directly receives power supplied from the battery 10 and steps down the output voltage of the battery 10 to charge a low-voltage battery (not shown) in addition to the motor that drives the compressor of the air conditioner. This corresponds to a DC-DC converter (not shown). The hybrid ECU 32 detects the operating status of the electric device 22. As will be described in detail later, the operating status of the electrical device 22 is used by the hybrid ECU 32 to correct the SOC upper limit value and the SOC lower limit value as a short-term correction factor.

  Here, as described above, the SOC of the battery 10 has a target value and an optimum range based on the target value. Further, by changing (correcting) the target value and the optimum range in consideration of various factors, further efficient use of energy and improvement of drivability can be expected. For example, when the battery 10 deteriorates with use, the internal resistance increases. For this reason, when the battery 10 is charged, the SOC is unlikely to increase. Therefore, by controlling the SOC in consideration of the deterioration of the battery 10, it is easy to secure energy for performing motor assist. Further, when the driver of the vehicle depresses the accelerator pedal more strongly, or when the switch for setting the traveling mode of the vehicle is set to the power mode, the motor generator 16 actively utilizes the power of the battery 10. By driving the vehicle or regenerating large electric power with the motor generator 16, the vehicle can be driven according to the driver's acceleration request and deceleration request, and drivability can be improved.

  However, when such various factors are taken into account, if the target SOC is corrected based on the respective factors, for example, the correction values for the respective correction factors are contradictory to each other, and appropriate correction can be performed as a whole. There is a fear of not being.

  Therefore, in this embodiment, the correction factor is classified into a long-term correction factor, a medium-term correction factor, and a short-term correction factor, and is corrected by a long-term correction factor, a correction target by a medium-term correction factor, and a short-term correction factor. The correction target by was made different. For this reason, when the SOC (charged state) of the battery 10 is controlled in consideration of various correction factors, it is possible to appropriately control the SOC of the battery 10 while suppressing the conflict of the respective correction factors. It becomes.

  Hereinafter, the correction target by each correction factor, the SOC control method of the battery 10 based on the corrected target value and the SOC range, and the like will be described in detail.

  FIG. 2 is a flowchart including a correction process based on each correction factor and a process for controlling the SOC of the battery 10 based on the corrected target value, etc., which is executed in the hybrid ECU 32 as the control unit.

  First, in step S100 of the flowchart of FIG. 2, a correction process based on a long-term correction factor is performed. However, since the correction process based on the long-term correction factor does not need to be frequently executed, for example, it is preferable to execute the correction process every predetermined time. Therefore, when the predetermined time has not elapsed since the previous execution, the process of step S100 may be skipped.

  In the present embodiment, the long-term correction factor is the degree of deterioration of the battery 10. Further, the correction target based on the long-term correction factor is the SOC target value (median value) as shown in FIG. Details of the correction processing based on the long-term correction factor will be described with reference to the flowchart of FIG.

  In step S200 of the flowchart of FIG. 4, it is determined whether or not the battery 10 has been replaced for reasons such as the lifetime. Whether or not the battery 10 has been replaced depends on, for example, that the power supply by the battery 10 is interrupted and then the power supply by the battery 10 is restarted, the SOC value of the battery 10 at the time of the restart, and the current and voltage in the battery 10 It can be determined from the estimated value of the internal resistance obtained from the above. If it is determined that the battery 10 has not been replaced, the process proceeds to step S210. If it is determined that the battery 10 has been replaced, the process proceeds to step S250.

  In step S210, an index indicating the degree of deterioration of the battery 10 is calculated. The index indicating the degree of deterioration can be calculated based on, for example, a temperature history and an overcharge / discharge history in addition to the duration of use of the battery 10. Specifically, the index indicating the degree of deterioration is calculated so as to indicate that the degree of deterioration has progressed as the duration of use of the battery 10 increases. Regarding the temperature history, the index indicating the degree of deterioration is calculated so as to indicate that the degree of deterioration has progressed as the number of times the temperature of the battery 10 exceeds the predetermined temperature range increases. Furthermore, regarding the overcharge / discharge history, the index indicating the degree of deterioration is calculated so as to indicate that the degree of deterioration has progressed as the number of times the SOC of the battery 10 deviates from the upper and lower limit values. However, the index indicating the degree of deterioration may be calculated based on at least one of the battery 10 usage duration, temperature history, and overcharge / discharge history. Alternatively, an estimated value of the internal resistance may be calculated from the relationship between the voltage and current of the battery 10, and an index indicating the degree of deterioration of the battery 10 may be calculated based on the internal resistance. The processing in step S210 corresponds to the deterioration degree estimation unit in the claims.

  In subsequent step S220, a correction amount corresponding to the degree of deterioration is calculated. Specifically, the correction amount is calculated such that the correction amount increases as the index indicating the deterioration degree calculated in step S210 indicates that the deterioration degree has advanced. In step S230, the corrected SOC target value is calculated by adding the calculated correction amount to the initial value of the SOC target value. In step S240, the calculated corrected SOC target value is stored in the memory. Thus, the stored corrected SOC target value is used to control the SOC of the battery 10 until the next time a new corrected SOC target value is calculated.

  On the other hand, in step S250 executed when it is determined in step S200 that the battery 10 has been replaced, the corrected SOC target value stored in the memory is reset. Thereby, when the hybrid ECU 32 controls the SOC of the battery 10 after replacement, the initial value of the SOC target value held by itself is used.

  Returning to the flowchart of FIG. In subsequent step S110, correction processing based on a medium-term correction factor is performed. In the present embodiment, the medium-term correction factor is a travel route to a target value set in the navigation device 20. Further, when the battery 10 can be charged by an external charging facility (so-called plug-in hybrid), the medium-term correction factors are that the battery 10 is externally charged (powered), and the fuel of the engine 18 is refueled. That is. The correction target based on the medium-term correction factor is a limit value of the SOC change amount per unit time as shown in FIG. Details of the correction process based on the medium-term correction factor will be described based on the flowcharts of FIGS. 5 and 6. The flowchart of FIG. 5 shows the correction process when the medium-term correction factor is the travel route, and the flowchart of FIG. 6 shows the correction process when the medium-term correction factor is external charging and refueling.

  In step S300 of the flowchart of FIG. 5, it is determined whether or not the navigation device 20 has set a travel route to the destination. In this determination process, when it is determined that the travel route is not set, the process illustrated in the flowchart of FIG. 5 ends. On the other hand, if it is determined that the travel route has been set, the process proceeds to step S310.

  In step S <b> 310, the hybrid ECU 32 receives information related to the set travel route (travel route information) from the navigation device 20. The travel route information includes information such as the travel route, road gradient information on the travel route, the shape, position, and number of curved roads. In the subsequent step S320, it is determined whether or not the road gradient in the travel route is greater than a predetermined reference gradient, or whether or not the number of curved roads having a curvature greater than or equal to a predetermined number is greater than the reference number. In this determination process, when it is determined that the road gradient in the travel route is larger than the predetermined reference gradient or the number of curved roads having a curvature greater than or equal to the predetermined number is larger than the reference number, the process proceeds to step S330. On the other hand, when it is determined that the road gradient in the travel route is equal to or less than the predetermined reference gradient and the number of curved roads having a curvature equal to or greater than the predetermined value is equal to or less than the reference number, the process proceeds to step S340.

  In step S330, the correction amount of the limit value that limits the actual SOC change amount per unit time is set to the first correction amount. On the other hand, in step S340, the correction amount is set to zero. In step S350, the correction limit value is calculated by correcting the initial value of the SOC change amount limit value using the set correction amount.

  As a result, when the road gradient included in the travel route is larger than the reference gradient, the limit value of the SOC change amount is corrected by the first correction amount as compared with the case where the road gradient is smaller than that. become. Accordingly, it is possible to allow a larger motor torque to be generated when traveling on an uphill road. Furthermore, it becomes possible to charge the battery 10 with larger regenerative electric power when traveling downhill. Further, when the number of curved roads included in the travel route is larger than the reference number, the limit value of the SOC change amount is corrected so as to be larger than when the number is less than the reference number. Therefore, deceleration at the time of entering the curved road makes it easier to collect larger regenerative electric power, and it is possible to generate a large assist torque by the motor when leaving the curved road.

  In the above example, the example in which the correction amount is switched in a binary manner based on whether the road gradient is larger than the reference gradient and whether the number of curved roads is larger than the reference number has been described. However, the correction amount may be set continuously according to the magnitude of the road gradient and / or according to the number of curved roads. In addition, the limit value of the SOC change amount may not be corrected over the entire travel route, but the limit value of the SOC change amount may be corrected only in a predetermined distance range including the corresponding part. Further, for example, when the travel route includes an uphill road with a large road gradient but the road slope of the downhill road is small, or conversely, the road route includes a downhill road with a large road gradient but the road slope of the uphill road is small, etc. Only one of the limit value for limiting the increase in the change amount and the limit value for limiting the decrease may be corrected.

  Next, the flowchart of FIG. 6 will be described. In step S400 of the flowchart of FIG. 6, it is determined whether the battery 10 is externally charged or the fuel of the engine 18 is refueled. In this determination process, if it is determined that the battery 10 is externally charged, the process proceeds to step S410. If it is determined that the fuel has been supplied, the process proceeds to step S420.

  In step S410, the correction amount of the limit value for limiting the actual SOC change amount per unit time is set to the first correction amount. On the other hand, in step S420, the correction amount is set to a second correction amount that is smaller than the first correction amount. In step S430, the correction limit value is calculated by correcting the initial value of the SOC change amount limit value using the set correction amount.

  Thereby, when the battery 10 is externally charged, the limit value of the SOC change amount of the battery 10 is increased, and when the fuel of the engine 18 is refueled, the SOC change amount limit of the battery 10 is more than that. The value can be reduced. As a result, when the battery 10 is externally charged, it is possible to actively utilize the externally charged electric power and to perform large torque assist by the motor generator 16 or travel of the vehicle only by the motor generator 16. On the other hand, when fuel is supplied, there is a margin in the amount of fuel, so that charging of the battery 10 during engine power generation can be allowed within a short time.

  Returning to the flowchart of FIG. In step S120, correction processing based on a short-term correction factor is performed. In the present embodiment, the short-term correction factor is the magnitude of the acceleration / deceleration request of the driver of the hybrid vehicle. The magnitude of the driver's acceleration / deceleration request can be estimated based on, for example, the degree of depression of the accelerator pedal or the brake pedal by the driver, or a signal from a switch that sets the traveling mode of the vehicle. The operating status of the electric device 22 that consumes the power of the battery 10 is also a short-term correction factor. As shown in FIG. 3, correction targets based on the short-term correction factor are an SOC upper limit value and an SOC lower limit value that define a range in which an actual SOC change is allowed with reference to the SOC target value. Details of the correction processing based on the short-term correction factor will be described with reference to the flowcharts of FIGS. The flowchart of FIG. 7 shows the correction processing when the short-term correction factor is the magnitude of the acceleration / deceleration request of the driver of the hybrid vehicle, and the flowchart of FIG. The correction process in a certain case is shown.

  In step S500 of the flowchart of FIG. 7, a sensor signal for detecting a driver's driving operation with respect to an accelerator pedal and a brake pedal and a signal from a switch for setting a traveling mode are captured. If the hybrid vehicle is not provided with a travel mode switch, only the sensor signal needs to be captured.

  In the subsequent step S510, it is determined whether or not the driver's acceleration / deceleration request is large based on the sensor signal and / or the switch signal. For example, if the driver's accelerator pedal or brake pedal is depressed quickly and the degree of depression is deep, or if the travel mode setting switch is set to the power mode, it is determined that the driver's acceleration / deceleration request is large. To do. The processing in step S510 corresponds to the acceleration / deceleration request estimation unit in the claims. If it is determined that the driver's acceleration / deceleration request is large, the process proceeds to step S520. On the other hand, if it is determined that the driver's acceleration / deceleration request is not large, the process proceeds to step S530.

  In step S520, a correction amount is set for increasing the SOC upper limit value and the SOC lower limit value so as to expand the range that the actual SOC can take. In other words, a correction amount for correcting the SOC upper limit value to a larger value and a correction amount for correcting the SOC lower limit value to a smaller value are set. At this time, the correction amount may be a constant value, or may be set to a continuous or multi-stage value according to the magnitude of the acceleration / deceleration request. On the other hand, in step S530, the correction amount is set to zero. For this reason, even if the correction amounts for the SOC upper limit value and the SOC lower limit value have been previously set in step S520, the previously set correction amount is reset by executing this step S530. In step S540, the correction upper limit value and the correction lower limit value are calculated by correcting the initial values of the SOC upper limit value and the SOC lower limit value using the set correction amount.

  Next, the flowchart of FIG. 8 will be described. In step S600 of the flowchart of FIG. 8, the hybrid ECU 32 detects the operating status of the electric device 22. The processing in step S600 corresponds to an operation status detection unit in the claims. In the subsequent step S610, it is determined whether or not the power consumption from the battery 10 is greater than a predetermined threshold based on the detected operating status of the electrical device 22. If it is determined that the power consumption by the electrical device 22 is greater than the predetermined threshold, the process proceeds to step S620. If it is determined that the power consumption is less than the predetermined threshold, the process proceeds to step S630.

  In step S620, as in step S520, a correction amount for correcting the SOC upper limit value and the SOC lower limit value so as to expand the range that can be taken by the actual SOC is set. At this time, the correction amount may be a fixed value, or may be set to a continuous or multi-stage value according to the power consumption of the electrical device 22. On the other hand, in step S630, the correction amount is set to zero. For this reason, even if the correction amounts of the SOC upper limit value and the SOC lower limit value were previously set in step S620, the correction amount set previously is reset by executing this step S630. In step S640, the correction upper limit value and the correction lower limit value are calculated by correcting the initial values of the SOC upper limit value and the SOC lower limit value using the set correction amount.

  Returning to the flowchart of FIG. As described above, when the correction process based on the long-term correction factor, the medium-term correction factor, and the short-term correction factor is completed, the process of step S130 is subsequently executed. In step S <b> 130, the charge / discharge amount in the battery 10 is calculated using the corrected SOC target value, the correction limit value, and the correction upper / lower limit value in consideration of the relationship with the actual SOC of the battery 10. That is, the hybrid ECU 32 discharges from the battery 10 according to the traveling state of the hybrid vehicle and generates a driving torque by the motor generator 16 or charges the battery 10 with regenerative power to thereby apply a braking torque to the motor generator 16. Is generated. As described above, the amount of charge / discharge when the battery 10 is charged or discharged falls within the range in which the actual SOC of the battery 10 is defined by the correction upper and lower limit values, and the amount of change per unit time. Is calculated to be less than or equal to the correction limit value. In step S140, the driving torque or the braking torque based on the calculated charge / discharge amount is output to the motor generator ECU 34 as a control command. In this way, the hybrid ECU 32 controls the power discharged from the battery 10 and the power charged in the battery 10.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the correction factor is classified into a long-term correction factor, a medium-term correction factor, and a short-term correction factor, and a correction target based on a long-term correction factor, a correction target based on a medium-term correction factor, and a short-term correction factor. The correction target by the factor was made different. However, the SOC target value and the upper and lower limit values may be corrected based on the long-term correction factor and the short-term correction factor without using the medium-term correction factor.

  In the above-described embodiment, as the short-term correction factor, the SOC upper limit value and the SOC lower limit value are corrected based on the magnitude of the acceleration / deceleration request of the driver of the hybrid vehicle. However, depending on the driving situation, only the SOC upper limit value may be corrected in a certain driving situation, and only the SOC lower limit value may be corrected in another driving situation.

  In the above-described embodiment, the limit value of the SOC change amount per unit time is corrected based on the travel route and / or refueling or power supply as a medium-term correction factor. However, the SOC target value may also be a medium-term correction factor, and the SOC change amount limit value may be corrected according to the SOC target value. For example, when the SOC target value is larger than the median value of the range defined by the upper and lower limit values, the increase side SOC change amount limit value is corrected to be smaller than when the SOC target value is smaller. In this case, it is preferable that the limit value for the SOC change amount on the decrease side is larger than the limit value for the SOC change amount on the increase side. On the contrary, when the SOC target value is smaller than the median value, correction is performed so that the limit value of the SOC change amount on the decrease side is smaller than when the SOC target value is larger. In this case, it is preferable that the limit value of the increase SOC change amount is larger than the limit value of the decrease SOC change amount. Thereby, it is possible to control the SOC target value so as to approach the median value.

  Furthermore, for example, when the vehicle is provided with a function of automatically adjusting the speed so that the vehicle follows the preceding vehicle, and when the frequency of sudden acceleration over a predetermined acceleration is a predetermined value or more, In order to suppress the rapid acceleration, the limit value of the change amount of the SOC target value on the decrease side may be corrected to be small. On the other hand, even if the frequency of sudden deceleration is high, the limit value for the amount of change in the increasing SOC target value is not reduced. This is because when a rapid deceleration is necessary to ensure safety, the regenerative brake is effectively operated and the large regenerative electric power can be recovered during the rapid deceleration.

  In the above-described embodiment, a hybrid vehicle including one motor generator 16 has been described. However, the hybrid vehicle generates a generator motor that generates electric power using engine power, a driving torque of the vehicle, and a braking torque. A motor generator may be provided separately.

DESCRIPTION OF SYMBOLS 10 ... Battery, 12 ... Current sensor, 14 ... Inverter, 16 ... Motor generator, 18 ... Engine, 20 ... Navigation device, 22 ... Electric equipment, 30 ... Battery ECU, 32 ... Hybrid ECU, 34 ... Motor generator ECU, 36 ... Engine ECU, 100 ... control system

Claims (13)

A motor (16) and an engine (18) as a drive source of the vehicle, a battery (10) for storing electric power for driving the motor, and a power generation unit (14,) for generating electric power for charging the battery 16), and a control system for controlling the state of charge of the battery.
An SOC detector (12, 30) for detecting the SOC of the battery;
The electric power discharged from the battery and the battery are charged so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling the power to be generated;
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S510) for estimating the magnitude of an acceleration / deceleration request by a driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and uses the acceleration / deceleration request estimation unit. The estimated acceleration / deceleration demand of the driver is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor,
The battery can be charged from the outside,
The control unit has a medium-term correction factor that the battery is externally charged and that the fuel of the engine is refueled, and a limit value of the SOC change amount per unit time according to the medium-term correction factor And controlling the electric power discharged from the battery and the electric power charged in the battery so that the amount of change in the SOC detected by the SOC detection unit is equal to or less than a limit value,
When the battery is externally charged, the control unit increases the limit value of the SOC change amount. When the fuel of the engine is refueled, the control unit is more than when the battery is externally charged. A control system that corrects the limit value of the SOC change amount to be small. A motor (16) and an engine (18) as a drive source of the vehicle, a battery (10) for storing electric power for driving the motor, and a power generation unit (14,) for generating electric power for charging the battery 16), and a control system for controlling the state of charge of the battery.
An SOC detector (12, 30) for detecting the SOC of the battery;
The electric power discharged from the battery and the battery are charged so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling the power to be generated;
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S510) for estimating the magnitude of an acceleration / deceleration request by a driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and uses the acceleration / deceleration request estimation unit. The estimated acceleration / deceleration demand of the driver is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor,
The control unit uses the magnitude of the SOC target value as a medium-term correction factor, corrects the limit value of the SOC change amount per unit time in accordance with the magnitude of the SOC target value, and is detected by the SOC detection unit And controlling the electric power discharged from the battery and the electric power charged in the battery so that the amount of change in the SOC is less than or equal to the limit value,
When the SOC target value is larger than the median of the range defined by the SOC upper and lower limit values, the control unit is configured so that the limit value for the increase amount of SOC change is smaller than when the SOC target value is smaller. Control system to compensate. A motor (16) and an engine (18) as a drive source of the vehicle, a battery (10) for storing electric power for driving the motor, and a power generation unit (14,) for generating electric power for charging the battery 16), and a control system for controlling the state of charge of the battery.
An SOC detector (12, 30) for detecting the SOC of the battery;
The electric power discharged from the battery and the battery are charged so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling the power to be generated;
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S510) for estimating the magnitude of an acceleration / deceleration request by a driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and uses the acceleration / deceleration request estimation unit. The estimated acceleration / deceleration demand of the driver is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor,
The control unit uses the magnitude of the SOC target value as a medium-term correction factor, corrects the limit value of the SOC change amount per unit time in accordance with the magnitude of the SOC target value, and is detected by the SOC detection unit And controlling the electric power discharged from the battery and the electric power charged in the battery so that the amount of change in the SOC is less than or equal to the limit value,
When the SOC target value is smaller than the median value of the range defined by the SOC upper and lower limit values, the control unit is configured so that the limit value of the SOC change amount on the decrease side is smaller than when the SOC target value is larger. Control system to compensate. A motor (16) and an engine (18) as a drive source of the vehicle, a battery (10) for storing electric power for driving the motor, and a power generation unit (14,) for generating electric power for charging the battery 16), and a control system for controlling the state of charge of the battery.
An SOC detector (12, 30) for detecting the SOC of the battery;
The electric power discharged from the battery and the battery are charged so that the SOC detected by the SOC detection unit falls within a range defined by the SOC upper limit value and the SOC lower limit value with reference to a predetermined SOC target value. A control unit (32) for controlling the power to be generated;
A deterioration degree estimation unit (S210) for estimating the deterioration degree of the battery;
An acceleration / deceleration request estimation unit (S510) for estimating the magnitude of an acceleration / deceleration request by a driver of the hybrid vehicle,
The control unit uses the deterioration degree of the battery estimated by the deterioration degree estimation unit as a long-term correction factor, corrects the SOC target value according to the long-term correction factor, and uses the acceleration / deceleration request estimation unit. The estimated acceleration / deceleration demand of the driver is a short-term correction factor, and the SOC upper limit value and the SOC lower limit value are corrected according to the short-term correction factor,
The hybrid vehicle has a function of automatically adjusting the speed so as to follow the preceding vehicle,
A control system that corrects the limit value of the change amount of the SOC target value on the decrease side to be small in order to suppress sudden acceleration when the frequency at which sudden acceleration over a predetermined acceleration is performed is a predetermined value or more. A navigation device (20) for guiding the hybrid vehicle to a destination;
When the route to the destination is set in the navigation device, the control unit uses the route as a medium-term correction factor, and corrects the limit value of the SOC change amount per unit time according to the medium-term correction factor. , the amount of change in SOC detected by the SOC detector unit, so that the limit value or less, in any one of claims 1 to 4 for controlling the power charged to the power and the battery is discharged from the battery The described control system. 6. The control system according to claim 5 , wherein the control unit corrects the limit value of the SOC change amount so that the limit value of the SOC change amount is larger when the road gradient in the route is larger than when the road gradient is small. The control system according to claim 5 , wherein the control unit corrects the limit value of the SOC change amount to be larger when the number of curved roads in the route is larger than when the number of curved roads is small. When the acceleration / deceleration request of the driver of the hybrid vehicle is large, the control unit expands a range defined by the SOC upper limit value and the SOC lower limit value compared to a case where the acceleration / deceleration request is small. The control system according to any one of claims 1 to 4 , wherein the SOC upper limit value and / or the SOC lower limit value are corrected as described above. An operation state detection unit (S600) for detecting an operation state of the electric device (22) mounted on the hybrid vehicle, which is operated by the electric power stored in the battery,
Wherein, as a short-term correction factors the operating status of the electric device that is detected by the operation status detection unit, according to any one of claims 1 to 4 to correct the SOC upper limit value and the SOC lower limit value Control system. When the controller determines that the power consumption of the battery is large based on the operating status of the electrical device, the control unit and the SOC upper limit value are compared with the case where it is determined that the power consumption of the battery is small. The control system according to claim 9 , wherein the SOC upper limit value and / or the SOC lower limit value is corrected so that a range defined by the SOC lower limit value is expanded. The control system according to any one of claims 1 to 10 , wherein the deterioration degree estimation unit estimates the deterioration degree of the battery based on at least one of a use duration time, a temperature history, and an overcharge / discharge history of the battery. . The control system according to claim 11 , wherein the control unit corrects the SOC target value so as to increase with the progress of the deterioration degree of the battery estimated by the deterioration degree estimation unit. The control system according to claim 11 or 12 , wherein the control unit resets a correction value for the SOC target value when the battery is replaced.

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