JP6413850B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control apparatus for a hybrid vehicle including an engine, an electric motor that can generate electric power using at least a part of power from the engine, and a battery that can be charged by electric power generated by the electric motor.

  Conventionally, a CD (Charge Depleting) mode in which a vehicle is driven by actively using electric power stored in a battery, and a CS (Charge Sustaining) in which an engine and an electric motor are controlled so that the SOC of the battery does not become lower than a predetermined value. ) Mode is known which can be set as a travel mode (see, for example, Patent Document 1). In this hybrid vehicle, when the CS mode is set and the SOC of the battery becomes equal to or higher than the first threshold value, the traveling mode is switched to the CD mode. Further, when the battery mode SOC is lower than the first threshold value and equal to or higher than the second threshold value lower than the predetermined value when the CS mode is set, the battery is charged with the power generated by the generator driven by the engine. Charged.

JP 2013-049381 A

  By the way, in the hybrid vehicle as described above, the auxiliary battery (second battery) is electrically connected to the battery (first battery) charged by the power generated by the generator via a DC / DC converter or the like. Thus, it will be possible to charge the auxiliary battery with the electric power stored in the battery to suppress the rise of the auxiliary battery (insufficient charging). However, when the CD mode and the CS mode are selectively set as the travel modes as described above, the battery SOC sufficient to charge the auxiliary battery can be secured depending on the travel mode setting. There is a risk of disappearing.

  Therefore, in the hybrid vehicle in which the CD mode and the CS mode are selectively set as the traveling mode, the present invention is configured so that the SOC of the first battery is determined when performing the pumping charging that charges the second battery with the electric power from the first battery. The main purpose is to ensure that it is adequately secured.

  A control apparatus for a hybrid vehicle according to the present invention includes an engine, an electric motor capable of generating electric power using at least a part of power from the engine, a first battery that can be charged by electric power generated by the electric motor, and the first In a hybrid vehicle control device including a second battery that can be charged by electric power from a battery, a CD mode that prioritizes electric travel in which operation of the engine is stopped according to the SOC of the first battery, and the engine One of the CS modes giving priority to the hybrid driving in which the vehicle is driven is set as the driving mode of the hybrid vehicle, and the pumping charging for charging the second battery with the electric power from the first battery is allowed. And the travel mode is set to the CS mode.

  The control device for the hybrid vehicle selects one of a CD mode in which priority is given to electric travel in which the operation of the engine is stopped and a CS mode in which priority is given to hybrid travel in which the engine is operated, in accordance with the SOC of the first battery. Set as the driving mode of the hybrid vehicle. Further, the control device sets the traveling mode to the CS mode when the pumping charging for charging the second battery with the electric power from the first battery is permitted. As a result, even when the first battery (SOC) is in a state where the CD mode should be set as the running mode when the execution of the pumping-out charging is allowed, the CS mode is set to the running mode, whereby the hybrid vehicle It becomes easy to drive the engine during the traveling. Therefore, when pumping-out charging is permitted, the hybrid vehicle is driven by at least a part of the power from the engine, or the electric power from the motor that generates electricity using at least a part of the power from the engine as necessary. 1 battery can be charged. As a result, it is possible to suppress a decrease in SOC due to the electric power stored in the first battery being consumed for running the hybrid vehicle. Therefore, when performing the pumping-up charging of the second battery, the SOC of the first battery Can be ensured sufficiently.

  Further, the control device sets the CD mode as the running mode when the SOC of the first battery is equal to or higher than a first threshold, and is allowed to perform the pumping charge, and the first battery. When the SOC is less than a second threshold value greater than the first threshold value, switching from the CS mode to the CD mode may be prohibited. As a result, it is possible to better suppress the decrease in the SOC of the first battery while the execution of the pump-out charging is allowed.

  Furthermore, the hybrid vehicle may have a mode switch that allows the driver to switch the driving mode, and the control device allows the driver to perform the pumping charging when the CD is allowed to be executed. When the mode is selected and the SOC of the first battery is greater than or equal to the second threshold, switching from the CS mode to the CD mode may be permitted. As a result, it is possible to allow the engine to stop operating when the pumping-out charging is executed.

  The first battery may be rechargeable with electric power from an external power source. Furthermore, the second battery may be an auxiliary battery that is electrically connected to the first battery via a voltage converter.

It is a schematic block diagram which shows the hybrid vehicle containing the control apparatus by this invention. It is explanatory drawing which shows the flow from the assembly start of the hybrid vehicle exported abroad to vehicle registration. 2 is a flowchart showing an example of a mode setting routine executed in the hybrid vehicle of FIG.

  Next, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 including a control device according to the present invention. A hybrid vehicle 20 shown in the figure is connected to an engine 22, a single pinion planetary gear 30, motors MG1 and MG2 each configured as a synchronous generator motor, a main battery (first battery) 40, and a main battery 40. Power control device (hereinafter referred to as “PCU”) 50 for driving motors MG1 and MG2, an auxiliary battery (second battery) 60, and hybrid electronic control as a control device according to the present invention for controlling the entire vehicle. And a unit (hereinafter, “electronic control unit” is referred to as “ECU”) 70.

  The engine 22 is an internal combustion engine that generates power by explosive combustion of a mixture of hydrocarbon fuel such as gasoline and light oil and air, and is controlled by an engine ECU 25 configured as a microcomputer including a CPU (not shown). . The planetary gear 30 includes a sun gear (first element) 31 connected to the rotor of the motor MG1, and a ring gear (second element) 32 connected to the drive shaft 35 and coupled to the rotor of the motor MG2 via the transmission 36. And a planetary carrier (third element) 34 that rotatably supports the plurality of pinion gears 33 and is connected to the crankshaft (output shaft) of the engine 22 via the damper 28. The drive shaft 35 is connected to left and right wheels (drive wheels) DW via a gear mechanism (not shown) and a differential gear 38. The transmission 36 performs connection between the rotor of the motor MG2 and the drive shaft 35 and release of the connection, and can set the gear ratio between the rotor and the drive shaft 35 in a plurality of stages. It is controlled by the ECU 70.

  The motor MG1 mainly operates as a generator that is driven by the load-driven engine 22 to generate (generate power), and the motor MG2 mainly uses the power from the main battery 40 and the power from the motor MG1. The regenerative braking force is output when the hybrid vehicle 20 is braked while operating as an electric motor driven by at least one of them to generate power. Motors MG1 and MG2 exchange power with main battery 40 via PCU 50.

  The main battery 40 is a lithium ion secondary battery or a nickel hydride secondary battery having a rated output voltage of 200 to 300 V, for example, and is managed by a battery ECU 45 configured as a microcomputer including a CPU (not shown). The battery ECU 45 inputs signals from the voltage sensor, current sensor, temperature sensor, etc. of the main battery 40, and based on the voltage between terminals, the charge / discharge current, etc., the SOC (charge ratio) of the main battery 40, the allowable charge power Win The allowable discharge power Wout and the like are calculated.

  The hybrid vehicle 20 of the present embodiment is configured as a plug-in hybrid vehicle that can charge the main battery 40 with electric power from the external power source 100 such as a household power source, and electric power that connects the main battery 40 and the PCU 50. It includes a charger 47 connected to the line. The charger 47 converts the AC power from the external power supply 100 supplied via the power plug into DC power, or converts the DC power voltage from the AC / DC converter into the main battery 40. A DC / DC converter to be supplied and the like are included (all are not shown) and controlled by the hybrid ECU 70.

  The PCU 50 includes, in addition to the first inverter that drives the motor MG1, the second inverter that drives the motor MG2, and the boost converter (voltage conversion module) that boosts the power from the main battery 40 (all not shown), Alternatively, it includes a DC / DC converter 54 that can step down the power from motor MG1 and supply it to auxiliary battery 60 and a plurality of auxiliary machines (not shown). The PCU 50 is controlled by a motor ECU 55 configured as a microcomputer including a CPU (not shown). The motor ECU 55 receives a command signal from the hybrid ECU 70, a pre-boosting voltage and a post-boosting voltage detected by a voltage sensor (not shown), a detected value of a resolver (not shown) that detects the rotational position of the rotor of the motors MG1 and MG2, The phase current applied to the motors MG1 and MG2 detected by the current sensor not to be input is input. The motor ECU 55 performs switching control of the first and second inverters and the boost converter based on these input signals. Further, motor ECU 55 calculates the rotational speed of the rotors of motors MG1 and MG2 based on the detected value of the resolver.

  The hybrid ECU 70 is configured as a microcomputer including a CPU (not shown) and the like, and exchanges various signals with the ECUs 25, 45, and 55 via a network (CAN). Furthermore, the hybrid ECU 70 inputs, for example, a signal from a start switch, an accelerator opening detected by an accelerator pedal position sensor, a vehicle speed detected by a vehicle speed sensor, a rotation speed of the motors MG1 and MG2, and the like. When the hybrid vehicle 20 travels, the hybrid ECU 70 sets a required torque Tr * required for travel based on the accelerator opening and the vehicle speed, and sets the target value for the main battery 40 based on the SOC of the main battery 40. Discharge power Pb * is set. Further, the hybrid ECU 70 sets the target engine power Pe * and the target rotational speed Ne * of the engine 22 based on the required torque Tr * and the target charge / discharge power Pb *, and transmits the target engine power Pe * and the target rotational speed Ne * to the required torque Tr *. Torque commands Tm1 * and Tm2 * for the corresponding motors MG1 and MG2 are set and transmitted to the motor ECU 55. The engine ECU 25 executes intake air amount control, fuel injection control, ignition timing control and the like based on the target engine power Pe * and the like, and the motor ECU 55 controls the PCU 50 based on the torque commands Tm1 * and Tm2 *.

  In the hybrid vehicle 20, the engine 22 is operated or stopped according to the required torque Tr *, the target charge / discharge power Pb *, and the like. When the operation of the engine 22 is stopped according to the required torque Tr *, the target charge / discharge power Pb *, etc., the motor MG2 is controlled so as to output a torque according to the required torque Tr * to the drive shaft 35. Thus, hybrid vehicle 20 travels (EV (electric) travel) with the power from motor MG2. When the engine 22 is operated and the main battery 40 is charged or discharged, the engine 22 outputs power corresponding to the sum of the power corresponding to the required torque Tr * and the target charge / discharge power Pb *. Controlled. At this time, the motors MG1 and MG2 are controlled so that a part (during charging) or all (during discharging) of the power output from the engine 22 is torque-converted together with the planetary gear 30 and output to the drive shaft 35. Thus, hybrid vehicle 20 travels (HV (hybrid) travel) using power from engine 22 (direct torque) and power from motor MG2. Furthermore, when the target charge / discharge power Pb * is zero and the engine 22 is operated according to the required torque Tr *, the motors MG1 and MG2 convert all of the output power of the engine 22 to the drive shaft 35 by torque conversion. Controlled to output. At this time, the main battery 40 is neither charged nor discharged, and the hybrid vehicle 20 travels (HV (hybrid) travel) with power (direct torque) from the engine 22 and power from the motor MG2.

  In addition, the hybrid ECU 70 prioritizes EV traveling in which the operation of the engine 22 is stopped over HV traveling in which the engine 22 is operated and prioritizes HV traveling over EV traveling in accordance with the SOC of the main battery 40. One of the CS modes to be performed is set as the travel mode of the hybrid vehicle 20. Thus, in the plug-in hybrid vehicle 20 having the main battery 40 that can be charged by the electric power from the external power supply 100, the setting of the CD mode and the CS mode is made possible, thereby providing an opportunity to execute EV traveling. It becomes possible to further increase the fuel consumption.

  Specifically, the hybrid ECU 70 sets a first threshold value S1 (for example, 25 to 25) in which the SOC of the main battery 40 is predetermined when the system is started (for example, immediately after the main battery 40 is charged with electric power from the external power supply 100). If it exceeds 35%, the CD mode is set to the running mode. Further, when the SOC of the main battery 40 becomes equal to or less than the first threshold value S1 during traveling of the hybrid vehicle 20 with the CD mode set, the hybrid ECU 70 switches the traveling mode from the CD mode to the CS mode. When the CS mode is set to the traveling mode, the engine 22 determination threshold (for example, engine start determination power) that is set sufficiently smaller than the threshold used when the CD mode is set is used. As a result, when the CS mode is set, the engine 22 that has been stopped is easily started. Therefore, the motor MG2 is driven by the electric power from the motor MG1 that generates electric power using at least a part of the power from the engine. Opportunities for charging the battery 40 can be increased.

  Furthermore, in the present embodiment, the hybrid ECU 70 is electrically connected to a mode switch 75 that allows the driver to switch the driving mode. Accordingly, the driver of the hybrid vehicle 20 can select a desired one of the CD mode and the CS mode as the travel mode by operating the mode switch 75. When the hybrid ECU 70 determines that the driver has selected the CD mode based on the signal from the mode switch 75, the hybrid ECU 70 sets the mode switch flag Fms to 1 and determines that the driver has selected the CS mode. The mode switch flag Fms is set to the value 0.

  FIG. 2 is an explanatory diagram showing a flow from the start of assembly of the hybrid vehicle 20 to be exported overseas to vehicle registration. As shown in the figure, when the assembly of the hybrid vehicle 20 is started, the main battery 40 delivered from the manufacturer is assembled to the vehicle body at a predetermined timing. The main battery 40 is delivered in a state of being charged to some extent at a manufacturing factory or the like. In addition, after the assembly of the hybrid vehicle 20 is completed, various inspections are performed, and the auxiliary battery 60 and the auxiliary device (load) are controlled in order to cut off the dark current of the entire vehicle and prevent the auxiliary battery 60 from being depleted. The short pin of the fuse provided in between is extracted. Thereafter, the hybrid vehicle 20 is transported to a loading port by a trailer or the like, and is loaded by self-propelled in a car dedicated ship at the loading port. The hybrid vehicle 20 transported to the unloading port by the automobile exclusive ship is landed by self-propelled from the automobile exclusive ship. Furthermore, the hybrid vehicle 20 is transported over a land route from a loading port to a dealer or the like by a trailer or the like, and a short pin is inserted in the dealer or the like. The hybrid vehicle 20 is parked in a parking space such as a dealer until vehicle registration is completed and delivered to the user.

  Here, even if the short pin is extracted, the remaining capacity of the auxiliary battery 60 decreases due to self-discharge. Therefore, when the hybrid vehicle 20 is exported, it is necessary to prevent the auxiliary battery 60 from rising (insufficiently charged) until the short pin once extracted is inserted again (during sea transportation). is there. For this reason, in the hybrid vehicle 20, the self-propelled timing between when the short pin is pulled out and when it is reinserted into the fuse or the like (for example, when loading on a trailer, loading on a dedicated car, At the time of unloading from a dedicated ship, etc., the pumping charge for charging the auxiliary battery 60 with the electric power from the main battery 40 is executed.

The pump-up charging of the auxiliary battery 60 is performed by controlling the DC / DC converter 54 when the hybrid vehicle 20 is traveling (running) in a state where all of the following conditions (1) to (6) are satisfied. Is done.
(1) The short pin is pulled out.
(2) The start switch is turned on and the system is activated (ReadyOn).
(3) The network (CAN) is not interrupted.
(4) The travel distance is less than a predetermined distance (for example, about 20 km).
(5) The SOC is set to a value that is greater than or equal to the charge start SOC (for example, a value of about 20%), which is the lowest SOC during transportation determined in consideration of the power required for pumping and charging, and smaller than the upper limit SOC. It is less than the charge stop SOC (for example, a value of about 30%).
(6) The allowable charging power Win is included in a range from a predetermined charging allowable threshold to a charging prohibition threshold.
In hybrid vehicle 20, a mode setting routine shown in FIG. 3 is executed by hybrid ECU 70 so that the SOC of main battery 40 is sufficiently ensured when pumping up auxiliary battery 60 is executed.

  The mode setting routine of FIG. 3 is repeatedly executed at predetermined intervals by the hybrid ECU 70 when the system of the hybrid vehicle 20 is activated between the time when the short pin is removed and the time when the hybrid vehicle 20 is reinserted into the fuse or the like. At the start of the mode setting routine, the hybrid ECU 70 (CPU) first starts a travel mode such as the values of various flags including the mode switch flag Fms, the travel distance of the hybrid vehicle 20, the SOC of the main battery 40, and the allowable charge power Win. Data necessary for setting is input (step S100). Further, based on the data input in step S100, the hybrid ECU 70 determines whether or not the pumping charge of the auxiliary battery 60 is permitted, that is, all the conditions (1) to (6) are satisfied. It is determined whether or not (step S110). When it is determined in step S110 that at least one of the above conditions (1) to (6) is not satisfied, the hybrid ECU 70 once ends this routine without executing the processing after step S100.

  When it is determined in step S110 that execution of the pumping charge of the auxiliary battery 60 is permitted, the hybrid ECU 70 determines whether or not the predetermined flag F is a value 0 (step S120). The flag F is set (reset) to a value of 0 when the system is started, for example. When this routine is executed for the first time after the system is started, an affirmative determination is made in step S120. If it is determined in step S120 that the flag F has a value of 0, the hybrid ECU 70 determines whether the CD mode is selected as the travel mode by the driver based on the value of the mode switch flag Fms input in step S100. Is determined (step S130).

  When it is determined in step S130 that the CD mode is not selected by the driver, the hybrid ECU 70 sets the CS mode to the traveling mode of the hybrid vehicle 20 and sets the flag F to 0 (step S135). ), This routine is temporarily terminated. When it is determined in step S130 that the CD mode is selected by the driver, the hybrid ECU 70 determines whether or not the SOC of the main battery 40 input in step S100 is equal to or greater than a predetermined second threshold S2. Is determined (step S140). For example, the second threshold value S2 is larger than the first threshold value S1 used for switching between the CD mode and the CS mode during normal driving of the hybrid vehicle 20, and is smaller than the above-described normal upper limit SOC (for example, the above-described charging). It is determined in advance to a value similar to the stop SOC).

  When it is determined in step S140 that the SOC is less than the second threshold value S2, the hybrid ECU 70 ensures that the SOC of the main battery 40 is secured when the auxiliary battery 60 is pumped up and charged. Then, without setting the CD mode selected by the driver, the CS mode is set to the running mode and the flag F is set to 0 (step S135), and this routine is terminated once. On the other hand, when it is determined in step S140 that the SOC is equal to or greater than the second threshold value S2, the hybrid ECU 70 sets the CD mode selected by the driver to the traveling mode and sets the flag F to the value 1 (step S150). ). Further, in step S150, the hybrid ECU 70 stores the SOC value of the main battery 40 input in step S100 as the SOC value Scd at the time of switching to the CD mode, and once ends this routine.

  When the process of step S150 is executed, when this routine is executed thereafter, it is determined in step S120 that the flag F has a value of 1. In this case, the hybrid ECU 70 calculates the SOC change amount (decrease amount) ΔS by subtracting the SOC input in step S100 from the SOC value Scd at the time of switching to the CD mode stored in step S150. (Step S160). Further, the hybrid ECU 70 determines whether or not the calculated SOC change amount ΔS is equal to or greater than a predetermined threshold value ΔSref (for example, a value of about 5%) (step S170).

  If it is determined in step S170 that the SOC change amount ΔS is less than the threshold value ΔSref, the hybrid ECU 70 temporarily ends this routine without switching the traveling mode, that is, while maintaining the traveling mode in the CD mode. On the other hand, when it is determined in step S170 that the SOC change amount ΔS is equal to or greater than the threshold value ΔSref, the hybrid ECU 70 switches the travel mode from the CD mode to the CS mode and sets the flag F to 0 (step S170). (S135) This routine is once terminated.

  As a result of the execution of the mode setting routine as described above, in the hybrid vehicle 20, all of the above conditions (1) to (6) are satisfied, and the pumping charging for charging the auxiliary battery 60 with the electric power from the main battery 40 is performed. If the execution is permitted, the traveling mode is basically set to the CS mode (step S135). Thus, even when the main battery 40 is in a state in which the CD mode should be set as the traveling mode when the pumping-out charging of the auxiliary battery 60 is permitted (even if SOC> S1), the CS mode Is set to the traveling mode, which makes it easier for the engine 22 to be operated (started) while the hybrid vehicle 20 is traveling (such as during self-running for loading or unloading). Therefore, when pumping and charging are allowed, the hybrid vehicle 20 is driven by at least a part of the power from the engine 22, or the MG 1 that generates power using at least a part of the power from the engine 22 as necessary. It becomes possible to charge the main battery 40 with electric power. As a result, the electric power stored in the main battery 40 can be prevented from being consumed (taken out) by the motor MG2 for traveling of the hybrid vehicle 20, and the SOC can be reduced. When charging is performed, the SOC of the main battery 40 can be ensured sufficiently.

  Moreover, in the hybrid vehicle 20, the pumping charge is allowed to be executed, and the SOC of the main battery 40 is less than the second threshold value S2, which is larger than the first threshold value S1 used for switching between the CD mode and the CS mode during normal driving. If it is, switching from the CS mode to the CD mode is prohibited (steps S140 and S135). As a result, it is possible to better suppress the decrease in the SOC of the main battery 40 while the pumping charge is allowed to be executed.

  Furthermore, in the hybrid vehicle 20, while the pumping charge is allowed to be executed, the CD mode is selected by the driver via the mode switch 75, and the SOC of the main battery 40 is equal to or higher than the second threshold value S2. The switching from the CS mode to the CD mode is allowed (steps S130 to S150). Thereby, the operation stop of the engine 22 can be permitted when the pumping-out charging is executed. As a result, for example, the hybrid vehicle 20 can set the CD mode when traveling in the cab of an automobile ship, and the operation of the engine 22 can be stopped to keep the air in the cab clean.

  As described above, in the hybrid vehicle 20, it is possible to ensure sufficient SOC of the main battery 40 when performing the pumping charging that charges the auxiliary battery 60 with the electric power from the main battery 40. .

  In addition, the period which permits the pumping-up charge of the auxiliary battery 60 is not limited to the above-mentioned transportation, and may be an arbitrary timing. The application target of the present invention is not limited to the plug-in hybrid vehicle 20 having the main battery 40 that can be charged by the electric power from the external power supply 100. That is, the present invention may be applied to a non-plug-in hybrid vehicle as long as either the CD mode or the CS mode can be set as the traveling mode. Further, although the hybrid vehicle 20 is a two-motor hybrid vehicle having a power distribution planetary gear 30, the present invention may be applied to a two-motor hybrid vehicle not having a power distribution planetary gear. In addition, the present invention may be applied to a single motor type hybrid vehicle or a series type hybrid vehicle. In the hybrid vehicle 20, a simple reduction gear mechanism may be employed instead of the transmission 36.

  And this invention is not limited to the said embodiment at all, and it cannot be overemphasized that a various change can be made within the range of the extension of this invention. Furthermore, the mode for carrying out the invention described above is merely a specific embodiment of the invention described in the column for solving the problem, and is described in the column for means for solving the problem. It is not intended to limit the elements of the invention.

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

  20 hybrid vehicle, 22 engine, 25 engine ECU, 28 damper, 30 planetary gear, 31 sun gear, 32 ring gear, 33 pinion gear, 34 planetary carrier, 35 drive shaft, 36 transmission, 38 differential gear, 40 main battery, 45 battery ECU, 47 charger, 50 PCU, 54 DC / DC converter, 55 motor ECU, 60 auxiliary battery, 70 hybrid ECU, 75 mode switch, 100 external power supply, MG1, MG2 motor.

Claims (1)

An engine, an electric motor capable of generating electric power using at least a part of power from the engine, a main battery that can be charged by electric power generated by the electric motor, and an auxiliary battery that can be charged by electric power from the main battery, In a hybrid vehicle control device including:
Depending on the SOC of the main battery, the driving mode of the hybrid vehicle is selected from either a CD mode that gives priority to electric driving in which the operation of the engine is stopped or a CS mode that gives priority to hybrid driving in which the engine is operated. And when the pumping charge for charging the auxiliary battery with the electric power from the main battery is permitted while the connection between the auxiliary battery and the auxiliary machine is cut off , the travel mode is set. A control apparatus for a hybrid vehicle, wherein the control mode is set to the CS mode.

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