JP2013071602A - Device and method for controlling hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively use electric power stored in a battery when a hybrid vehicle travels on an upward slope.SOLUTION: A device for controlling a hybrid vehicle on which a battery for storing electric power to drive a motor for allowing the hybrid vehicle to travel is mounted includes: a slope information acquisition section acquiring information on a slope of a road surface on which the hybrid vehicle travels; and a controller controlling, on the basis of the result acquired at the slope information acquisition section, discharge an output of the battery to a first output higher than a reference output when the slope of the road surface is higher than a slope threshold.

Description

  The present invention relates to a control apparatus for a hybrid vehicle including a battery that stores electric power for driving a motor that drives the hybrid vehicle.

  As a power source for running a hybrid vehicle, a hybrid vehicle having a motor that operates with electric power supplied from a battery and an engine is known. The hybrid vehicle achieves excellent power performance by optimally distributing the driving force of the engine and the motor according to various driving conditions.

JP 2008-265636 A JP 2002-291104 A JP-A-11-187777 JP 2007-221914 A

  However, in the conventional hybrid vehicle, when traveling uphill, only the engine is used and the motor is not fully used. For example, when the road surface from the starting point to the destination is a climbing hill, the battery is only a heavy object because the motor is used less frequently. In view of the above, an object of the present invention is to effectively utilize the electric power stored in the battery when the hybrid vehicle travels uphill.

  In order to solve the above-described problems, a hybrid vehicle control device according to the present invention is (1) a hybrid vehicle control device equipped with a battery that stores electric power for driving a motor that drives the hybrid vehicle, Based on the acquisition result of the gradient information acquisition unit and the gradient information acquisition unit that acquires information about the gradient of the road surface on which the hybrid vehicle travels, the discharge output of the battery is calculated when the road surface gradient is higher than a gradient threshold value. And a controller that controls the first output to be higher than the reference output.

  (2) In the configuration of (1), the controller can control the discharge power of the battery to the first output only when the amount of charge of the battery is higher than a discharge threshold. According to the configuration of (2), when the hybrid vehicle travels uphill, the power stored in the battery can be used more effectively.

  (3) In the configuration of (2) above, a storage amount information acquisition unit that acquires information about the storage amount of the battery, a temperature information acquisition unit that acquires information about the temperature of the battery, the temperature of the battery, A storage unit that stores correspondence information in which the storage amount of the battery, a road surface gradient, and the first output are associated with each other, and the controller includes the gradient information acquisition unit and the storage amount information acquisition The first output is determined by reading out information on the first output corresponding to the acquisition result of the temperature information acquisition unit from the storage unit. According to the structure of (3), the appropriate battery output according to the road surface gradient can be obtained.

  (4) In the configurations of (1) to (3), when the road surface gradient decreases after the controller sets the discharge output of the battery as the first output, the controller outputs the first output. And the discharge output of the battery is controlled to a second output that is lower and higher than the reference output. According to the structure of (4), since the fall of the electrical storage amount of a battery is suppressed, when a road surface changes from a climbing slope to a flat ground, a hybrid vehicle can be driven using the electric power stored in the battery.

  (5) In the configurations of (1) to (4) above, the gradient information acquisition unit may be a road surface gradient sensor mounted on the hybrid vehicle.

  In order to solve the above-described problems, a hybrid vehicle control method according to the present invention includes (6) a hybrid vehicle control method including a battery that stores electric power for driving a motor that drives the hybrid vehicle. A gradient information acquisition step for acquiring information relating to the gradient of the road surface on which the vehicle travels, and a first higher battery than the reference output when the road gradient is higher than a gradient threshold based on the acquisition result in the gradient information step. And a discharge step for discharging at an output of.

  (7) In the configuration of (6) above, further including a storage amount information acquisition step of acquiring information related to the storage amount of the battery, and in the discharging step, when the storage amount of the battery is higher than a discharge threshold Only the battery can be discharged at the first output. According to the configuration of (7), when the hybrid vehicle travels uphill, the power stored in the battery can be used more effectively.

  (8) In the configuration of (7), the storage unit of the hybrid vehicle associates the temperature of the battery, the amount of electricity stored in the battery, the gradient of the road surface, and the first output. Is stored, and further includes a temperature information acquisition step of acquiring information related to the temperature of the battery. In the discharging step, the temperature information acquisition step, the storage amount acquisition step, and the gradient information acquisition step are acquired. The first output is determined by reading out information on the first output corresponding to the acquisition result from the storage unit. According to the structure of (8), the appropriate battery output according to the road surface gradient can be obtained.

  (9) In the configurations of (6) to (8) above, in the discharging step, after the battery is discharged at the first output, if the road surface gradient decreases, the discharge is more than the first output. The battery can be discharged with a second output that is low and higher than the reference output. According to the structure of (9), since the fall of the electrical storage amount of a battery is suppressed, when a road surface changes from a climbing slope to a flat ground, a hybrid vehicle can be driven using the electric power stored in the battery.

  According to the present invention, when the hybrid vehicle travels uphill, the power stored in the battery can be used effectively.

It is a block diagram of a hybrid vehicle. It is a block diagram of a control apparatus. It is the flowchart which showed the control method of the battery by a control apparatus.

    Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a hardware configuration in a part of a hybrid vehicle according to an embodiment of the present invention.

  Referring to FIG. 1, hybrid vehicle 1 includes a battery 11, smoothing capacitors C1 and C2, a voltage converter 12, an inverter 13, a motor generator MG1, a motor generator MG2, and a power split planetary gear P1. , Including a reduction planetary gear P2, a reduction gear D, an engine 14, a relay 15, an ECU 30, a monitoring unit 31, and a storage unit 32.

  As the battery 11, an assembled battery in which a plurality of secondary batteries are connected in series can be used. A nickel metal hydride battery or a lithium ion battery can be used as the secondary battery. Hybrid vehicle 1 further includes a power supply line PL1 and a ground line SL. The battery 11 is connected to the voltage converter 12 via system main relays SMR-G, SMR-B, and SMR-P constituting the relay 15. A system main relay SMR-G is connected to the plus terminal of the battery 11, and a system main relay SMR-B is connected to the minus terminal of the battery 11. The system main relay SMR-P and the precharge resistor 17 are connected in parallel to the system main relay SMR-B.

  The ECU 30 turns off all the system main relays SMR-G, SMR-B, and SMR-P when the current is interrupted, that is, when the ignition switch is in the OFF position. That is, the exciting current for the coils of the system main relays SMR-G, SMR-B, and SMR-P is turned off. The ECU 30 may be a CPU or an MPU, or may include an ASIC circuit that executes at least a part of processes executed in these CPUs.

  When the hybrid system is activated (when the main power supply is connected), that is, for example, when the driver depresses the brake pedal and pushes the push start switch, the ECU 30 first turns on the system main relay SMR-G. Next, the ECU 30 turns on the system main relay SMR-P to perform precharging.

  A precharge resistor 17 is connected to the system main relay SMR-P. For this reason, even if the system main relay SMR-P is turned on, the input voltage to the inverter 13 rises gently, and the occurrence of an inrush current can be prevented.

  When the position of the ignition switch is switched from the ON position to the OFF position, the ECU 30 first turns off the system main relay SMR-B, and then turns off the system main relay SMR-G. Thereby, the electrical connection between the battery 11 and the inverter 13 is cut off, and the power supply is cut off. System main relays SMR-B, SMR-G, and SMR-P are controlled to be in a conductive / non-conductive state according to a control signal supplied from ECU 30.

  Capacitor C1 is connected between power supply line PL1 and ground line SL, and smoothes the voltage between the lines. The voltage converter 12 boosts the voltage across the capacitor C1. Capacitor C2 smoothes the voltage boosted by voltage converter 12. Inverter 13 converts the DC voltage applied from voltage converter 12 into a three-phase AC and outputs the same to motor generator MG2. Reduction planetary gear P <b> 2 transmits the power obtained by motor generator MG <b> 2 to reduction device D to drive hybrid vehicle 1. The power split planetary gear P1 splits the power obtained by the engine 14 into two paths, one of which is transmitted to the wheels via the speed reducer D, and the other drives the motor generator MG1 to generate power. The electric power generated by the motor generator MG1 is used to drive the motor generator MG2, thereby assisting the engine 14. Reduction planetary gear P2 transmits the power transmitted through reduction gear D to motor generator MG2 when the hybrid vehicle decelerates, and drives motor generator MG2 as a generator. The electric power obtained by motor generator MG2 is converted from a three-phase AC to a DC voltage in inverter 13 and transmitted to voltage converter 12. At this time, the ECU 30 controls the voltage converter 12 to operate as a step-down circuit. The electric power stepped down by the voltage converter 12 is stored in the battery 11.

The monitoring unit 31 acquires information regarding the voltage, current, and temperature of the battery 11.
The monitoring unit 31 may be unitized with the battery 11. When the secondary battery constituting the battery 11 is a lithium ion battery, the voltage value acquired by the monitoring unit 31 may be the voltage value of each battery cell (unit cell). When the secondary battery constituting the battery 11 is a nickel metal hydride battery, the voltage value detected by the monitoring unit 31 may be the voltage value of each battery module (single battery in which a plurality of battery cells are connected in series). Good. The temperature of the battery 11 may be acquired via a thermistor (not shown). The ECU 30 controls the state of charge (SOC) of the battery 11 to be maintained within a control range defined by the control upper limit value and the control lower limit value.

  Next, a hybrid vehicle control device (hereinafter referred to as a control device) will be described with reference to the functional block diagram of FIG. Elements that are the same as those in FIG. 1 are given the same reference numerals. The control device 10 includes a battery 11, an ECU (corresponding to a controller) 30, a storage unit 32, a storage amount acquisition unit 82, a gradient information acquisition unit 83, and a temperature information acquisition unit 84.

  The gradient information acquisition unit 83 acquires information related to the road surface gradient. The gradient information acquisition unit 83 may be a road surface gradient sensor that detects the gradient θ of the road surface on which the hybrid vehicle 1 travels. The road surface gradient sensor may be an inclination sensor. In this case, the ECU 30 calculates the slope of the road surface based on the output result of the inclination sensor. Here, as described above, the ECU 30 may include a CPU, an MPU, or an ASIC circuit that executes at least a part of processing executed in these CPUs, etc., and the number of CPUs is not limited. . Therefore, for example, the CPU that performs charge / discharge control of the battery 11 and the CPU that calculates the gradient of the road surface based on the output result of the inclination sensor may be different.

  However, the gradient information acquisition unit 83 includes a vehicle position detection device that detects the current position of the hybrid vehicle 1 (see FIG. 1), and a map data storage unit that stores road map data including road surface gradient information. It may be a navigation device. In this case, the ECU 30 can acquire information on the road surface gradient θ on which the hybrid vehicle 1 travels by reading road surface gradient information corresponding to the current position of the hybrid vehicle 1 from the map data storage unit. Here, the map data storage unit may be the storage unit 32. In this case, the gradient information acquisition part 83 is implement | achieved when a vehicle position detection apparatus and the memory | storage part 32 cooperate.

  The storage amount information acquisition unit 82 acquires information related to the storage amount of the battery 11. The storage amount information acquisition unit 82 may be a voltage sensor included in the monitoring unit 31 illustrated in FIG. In this case, the ECU 30 calculates the amount of electricity stored in the battery 11 from the information regarding the voltage acquired by the voltage sensor.

  The temperature information acquisition unit 84 acquires information related to the temperature of the battery 11. The temperature information acquisition unit 84 may be a thermistor included in the monitoring unit 31 illustrated in FIG. In this case, the ECU 30 calculates the temperature of the battery 11 from the information regarding the temperature acquired by the thermistor.

  The storage unit 32 stores correspondence information in which the temperature of the battery 11, the amount of power stored in the battery 11, the road surface gradient, and the first output are associated with each other. Here, the first output means an output required for the battery 11 when the hybrid vehicle 1 travels uphill as will be described later. The output of the battery 11 depends on the temperature of the battery 11 and the amount of electricity stored. Further, when the road surface has a large gradient, the output of the battery 11 is increased to more effectively use the electric power stored in the battery 11. be able to. Therefore, the correspondence information is stored in the storage unit 32 in advance, and the correspondence stored in the storage unit 32 based on the acquisition results of the storage amount information acquisition unit 82, the gradient information acquisition unit 83, and the temperature information acquisition unit 84. An appropriate output corresponding to the road surface gradient can be obtained from the information.

  Furthermore, after the output of the battery 11 is controlled to the first output, when the road surface gradient θ decreases, the output of the battery 11 is reduced from the first output to the second output. When the road surface gradient θ decreases, it indicates that the slope is approaching the end, and when the road surface changes from a slope to a flat ground by reducing the output of the battery 11, the usage time of the battery 11 on a flat ground Can be lengthened. Similar to the first output, the second output is stored in the storage unit 32 together with information related to the temperature of the battery 11, the amount of electricity stored in the battery 11, and the gradient of the road surface.

  Here, the first output is higher than the reference output of the battery 11. The reference output of the battery 11 means the output of the battery 11 when the hybrid vehicle 1 stopped on the plane is initially started. That is, the hybrid vehicle 1 has a traveling mode in which the vehicle 11 travels using only the electric power of the battery 11 at the initial start, and the output of the battery 11 at the initial automatic time becomes the reference output. Further, the second output is higher than the reference output and lower than the first output.

  Next, a battery control method by the control device 10 will be described with reference to the flowchart of FIG. In step S101, the ECU 30 determines whether or not the charged amount of the battery 11 is higher than the discharge threshold. If the charged amount of the battery 11 is higher than the discharge threshold, the ECU 30 proceeds to step S102. Here, it is preferable that the discharge threshold is a storage amount close to a full charge of the battery 11. When the battery 11 is nearly fully charged, the electric power necessary for the hybrid vehicle 1 to travel uphill is stored in the battery 11, and the electric power stored in the battery 11 can be used effectively.

  In step S102, the ECU 30 determines whether or not the road surface gradient θ is larger than the gradient threshold value. If the road surface gradient θ is larger than the gradient threshold value, the ECU 30 proceeds to step S103. Here, the gradient threshold corresponds to a case where the output at the start of the vehicle exceeds the output upper limit value of the battery 11. That is, the gradient threshold value is determined from the output upper limit value, and specifically, is determined by the hardware configuration such as the output condition of the battery 11 and the output condition of the motor generator MG2.

  In step S <b> 103, the ECU 30 determines the first storage amount, temperature, and road surface gradient θ corresponding to the current battery 11 based on the acquisition results of the storage amount information acquisition unit 82, the gradient information acquisition unit 83, and the temperature information acquisition unit 84. Are read out from the correspondence information stored in the storage unit 32 to determine the first output. Thereby, the hybrid vehicle 1 travels in a state where the discharge output of the battery 11 is controlled to the first output. In this case, the travel mode of the hybrid vehicle 1 may be an EV travel mode that travels using only the power of the battery 11 or an HV travel mode that travels using both the power of the battery 11 and the power of the engine 14. .

  In step S105, the ECU 30 determines whether or not the charged amount of the battery 11 has become smaller than the lower limit value. If the charged amount of the battery 11 has become smaller than the lower limit value, the ECU 30 proceeds to step S110 and proceeds to step S110. If the amount of stored power does not become smaller than the lower limit value, the process proceeds to step S106. Here, the lower limit value can be appropriately set from the viewpoint of preventing overdischarge of the battery 11. In step S110, the ECU 30 stops discharging the battery 11. In this case, the hybrid vehicle 1 is switched to a travel mode using only the engine 14.

  In step S106, the ECU 30 determines whether or not the road surface gradient θ is lower than the gradient threshold value. If the road surface gradient θ is lower than the gradient threshold value, the ECU 30 proceeds to step S107, and the road surface gradient θ is increased. If it is not lower than the gradient threshold, the process returns to step S104.

  In step S <b> 107, the ECU 30 performs the second operation corresponding to the current storage amount, temperature, and road surface gradient θ of the battery 11 based on the acquisition results of the storage amount information acquisition unit 82, the gradient information acquisition unit 83, and the temperature information acquisition unit 84. Is read out from the correspondence information stored in the storage unit 32, and the second output is determined. Thereby, the output of the battery 11 falls from the 1st output to the 2nd output, and the fall of the storage amount of the battery 11 can be suppressed. As a result, when the road surface changes from climbing to flat, the motor generator MG2 can be driven using the electric power stored in the battery 11, that is, the hybrid vehicle 1 can be driven.

  In step S108, the ECU 30 determines whether or not the charged amount of the battery 11 has become smaller than the lower limit value. If the charged amount of the battery 11 has become smaller than the lower limit value, the ECU 30 proceeds to step S110. If the amount of stored power does not become smaller than the lower limit value, the process proceeds to step S109. The meaning of the lower limit value is omitted because it has been described above. In step S110, the ECU 30 stops discharging the battery 11. In this case, the hybrid vehicle 1 is switched to a travel mode using only the engine 14.

  In step S109, the ECU 30 determines whether or not the road surface gradient θ is 0 degrees. If the road surface gradient θ is 0 degrees, the ECU 30 proceeds to step S110, and the road surface gradient θ is 0 degrees. If not, the process returns to step S107.

  As described above, according to the present embodiment, the hybrid vehicle 1 can be driven using the electric power of the battery 11 when the road surface gradient θ is larger than the gradient threshold value. Thereby, the electric power stored in the battery 11 can be used effectively.

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 10 Control apparatus 11 Battery 12 Voltage converter 13 Inverter 14 Engine 15 Relay 17 Precharge resistance 30 ECU31 Monitoring unit 32 Memory | storage part 82 Electricity storage amount information acquisition part 83 Inclination information acquisition part 84 Temperature information acquisition part

Claims (9)

A control device for a hybrid vehicle equipped with a battery for storing electric power for driving a motor that drives the hybrid vehicle,
A gradient information acquisition unit for acquiring information on the gradient of the road surface on which the hybrid vehicle runs;
And a controller that controls the discharge output of the battery to a first output higher than a reference output when the road surface gradient is higher than a gradient threshold value based on an acquisition result of the gradient information acquisition unit. A control device for a hybrid vehicle.   2. The control apparatus for a hybrid vehicle according to claim 1, wherein the controller controls the discharge power of the battery to the first output only when a storage amount of the battery is higher than a discharge threshold. A storage amount information acquisition unit for acquiring information related to a storage amount of the battery;
A temperature information acquisition unit for acquiring information related to the temperature of the battery;
A storage unit that stores correspondence information in which the temperature of the battery, the storage amount of the battery, the slope of the road surface, and the first output are associated with each other;
The controller determines the first output by reading out information on the first output corresponding to the acquisition results of the gradient information acquisition unit, the storage amount information acquisition unit, and the temperature information acquisition unit from the storage unit. The control apparatus for a hybrid vehicle according to claim 2.   When the road surface slope is lowered after the discharge output of the battery is the first output, the controller outputs a second output that is lower than the first output and higher than the reference output. The hybrid vehicle control device according to any one of claims 1 to 3, wherein a discharge output of the battery is controlled.   The hybrid vehicle control device according to any one of claims 1 to 4, wherein the gradient information acquisition unit is a road surface gradient sensor mounted on the hybrid vehicle. In a control method of a hybrid vehicle equipped with a battery that stores electric power for driving a motor that drives the hybrid vehicle,
A gradient information acquisition step of acquiring information relating to a gradient of a road surface on which the hybrid vehicle travels;
And a discharging step of discharging the battery with a first output higher than a reference output when a road surface gradient is higher than a gradient threshold value based on a result obtained in the gradient information step. Control method. Furthermore, it has a storage amount information acquisition step of acquiring information regarding the storage amount of the battery,
The method for controlling a hybrid vehicle according to claim 6, wherein, in the discharging step, the battery is discharged with the first output only when a storage amount of the battery is higher than a discharge threshold. The storage unit of the hybrid vehicle stores correspondence information that associates the temperature of the battery, the amount of electricity stored in the battery, the slope of the road surface, and the first output,
And a temperature information obtaining step for obtaining information on the temperature of the battery,
In the discharging step, the first output is read out from the storage unit by reading information about the first output corresponding to the acquisition result acquired in the temperature information acquisition step, the storage amount acquisition step, and the gradient information acquisition step. 8. The method for controlling a hybrid vehicle according to claim 7, wherein the output is determined.   In the discharging step, after the battery is discharged at the first output, if the road surface slope decreases, the second output is lower than the first output and higher than the reference output. The method for controlling a hybrid vehicle according to claim 6, wherein the battery is discharged.

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