JP2023036119A - Control device of hybrid vehicle - Google Patents

Abstract

To suppress a situation that desired torque cannot be outputted to a driving shaft, while suppressing a vehicle from vibrating.SOLUTION: When a vehicle speed is below or equal to a predetermined vehicle speed, temporary output power of a first motor is set so that the power is constant in a range of a hysteresis width with power which should be outputted from the first motor as a center, and a second motor is controlled so that the second motor is driven in a range of power limit values of the second motor based on the set temporary output power and an output limit of a battery, where the hysteresis width is set on the basis of, an input/output difference as a difference between the output limit and an input limit of the battery.SELECTED DRAWING: Figure 4

Description

The present invention relates to a control device for a hybrid vehicle, and more specifically, an engine, first and second motors, planetary gears, and a battery are mounted on a hybrid vehicle to control the engine and the first and second motors. The present invention relates to a hybrid vehicle control device.

Conventionally, as a hybrid vehicle control device of this type, there has been proposed one in which an engine, first and second motors, planetary gears, and a battery are all mounted in a hybrid vehicle (see, for example, Patent Document 1). ). The planetary gear has three rotating elements connected to the rotating shaft of the first motor, the output shaft of the engine, and the drive shaft connected to the drive wheels. The rotation shaft of the second motor is connected to the drive shaft. A battery exchanges power with the first and second motors. In this device, when the electric power generated by the first and second motors is greater than the input limit of the battery at the time of starting, the first motor drives the engine, the first motor consumes electric power, and then the first motor The engine and the first and second motors are controlled so that the vehicle starts running with power output from the engine that generates power to the drive shaft. Since the vehicle starts while preventing the battery from being charged with electric power exceeding the input limit, the starting performance can be ensured while protecting the battery.

JP 2004-357459 A

In the hybrid vehicle control apparatus described above, when the power output from the engine fluctuates, the torques of the first and second motors fluctuate. Since the second motor inputs and outputs power to the drive shaft, vehicle vibration occurs when the torque of the second motor fluctuates. As a method of suppressing such vehicle vibration, the temporary output power of the first motor is set so as to be constant within the range of the hysteresis width centered on the target power based on the torque command of the first motor, and the temporary output power and the battery A possible method is to drive the second motor within the range of the power limit value of the second motor based on the output limit of . However, when the hysteresis width is constant, the power limit value of the second motor becomes small depending on the value of the temporary output power, and the second motor cannot output sufficient torque, and the desired torque cannot be output to the drive shaft. If the hysteresis width is reduced in order to output a desired torque to the drive shaft, vehicle vibration will increase.

A main object of the hybrid vehicle control device of the present invention is to suppress the inability to output a desired torque to the drive shaft while suppressing vibration of the vehicle.

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

The hybrid vehicle control device of the present invention includes:
an engine, a first motor, a planetary gear in which three rotating elements are connected to a rotary shaft of the first motor, an output shaft of the engine, and a drive shaft coupled to drive wheels; A control device for a hybrid vehicle that includes a connected second motor and a battery that exchanges electric power with the first and second motors, and is mounted on the hybrid vehicle to control the engine and the first and second motors. There is
When the vehicle speed is equal to or lower than a predetermined vehicle speed, the provisional output power of the first motor is set so as to be constant within the range of the hysteresis width centered on the target power to be output from the first motor, and the set provisional output power is set. controlling the second motor so that the second motor is driven within a power limit value range of the second motor based on the power and the output limit of the battery;
The hysteresis width is set based on an input/output difference as a difference between an output limit and an input limit of the battery.

In the hybrid vehicle control system of the present invention, when the vehicle speed is equal to or lower than the predetermined vehicle speed, the temporary output power of the first motor is kept constant within the range of the hysteresis width around the target power to be output from the first motor. is set, and the second motor is controlled so that the second motor is driven within the range of the power limit value of the second motor based on the set temporary output power and the output limit of the battery. As the "predetermined vehicle speed", a vehicle speed predetermined as a threshold value for determining whether or not there is a high possibility that the vehicle will stop can be used. Then, the hysteresis width is set based on the input/output difference, which is the difference between the battery output limit and input limit. As a result, even when the absolute value of either the output limit or the input limit of the battery becomes 0 due to deterioration of the battery condition, the hysteresis width is prevented from becoming 0, The output power can be brought closer to the target power of the first motor. Since it is possible to suppress the hysteresis width from reaching the value of 0, it is possible to suppress frequent changes in the provisional output power of the first motor as compared with the case where the hysteresis width has the value of 0, thereby suppressing torque fluctuations of the second motor. It is possible to suppress the vibration of the vehicle. Also, since the tentative output power of the first motor can be brought close to the target power of the first motor, the tentative output power becomes excessively large relative to the target power of the first motor, and the power limit value of the second motor becomes too small. Therefore, it is possible to prevent the drive of the second motor from being excessively limited, and prevent the output of the desired torque from being output to the drive shaft. As a result, it is possible to suppress the inability to output the desired torque to the drive shaft while suppressing the vibration of the vehicle.

In such a hybrid vehicle control device of the present invention, the hysteresis width may be set to be smaller when the input/output difference is small than when it is large. By doing so, it is possible to further suppress the inability to output the desired torque to the drive shaft.

In this case, the hysteresis width may be set to the input/output difference, or may be set to a value obtained by multiplying the input/output difference by a predetermined positive coefficient. By doing so, the hysteresis width can be set more appropriately.

Further, in the hybrid vehicle control apparatus of the present invention, the hysteresis width may be set to the smaller value of the input/output difference and the maximum value of the input/output difference that allows vibration of the vehicle. By doing so, the vibration of the vehicle can be suppressed within the allowable range.

1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the invention; FIG. 4 is an explanatory diagram showing an example of a relationship between a temperature Tb of a battery 50 and basic values Winb and Woutb; FIG. FIG. 4 is an explanatory diagram showing an example of a relationship between a charge ratio SOC of a battery 50 and an input/output limit correction coefficient; 4 is a flowchart showing an example of a drive control routine executed by the HVECU 70 of the hybrid vehicle 20 of the embodiment; 4 is a flowchart showing an example of a drive control routine executed by the HVECU 70 of the hybrid vehicle 20 of the embodiment; FIG. 4 is an explanatory diagram showing an example of a required torque setting map; FIG. 5 is an explanatory diagram showing an example of torque limits Tm1min and Tm1max of the motor MG1; FIG. 9 is an explanatory diagram showing how a temporary power Pm1his of the motor MG1 is set;

Next, a mode for carrying out the present invention will be described using examples.

FIG. 1 is a configuration diagram showing the outline of the configuration of a hybrid vehicle 20 as one embodiment of the present invention. As illustrated, the hybrid vehicle 20 of the embodiment includes an engine 22, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50 as a power storage device, and an electronic control unit for hybrid (hereinafter referred to as " HVECU”) 70.

The engine 22 is configured as an internal combustion engine that outputs power using gasoline, light oil, or the like as fuel. The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24 .

Although not shown, the engine ECU 24 is configured as a microprocessor centering on a CPU. In addition to the CPU, the engine ECU 24 includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. . Signals from various sensors necessary for controlling the operation of the engine 22 are input to the engine ECU 24 through an input port. Signals input to the engine ECU 24 include, for example, a crank angle θcr from a crank position sensor 23 that detects the rotational position of the crankshaft 26, and a cooling water temperature from a water temperature sensor (not shown) that detects the temperature of the cooling water of the engine 22. Tw can be mentioned. In addition, the throttle opening TH from a throttle valve position sensor (not shown) that detects the position of the throttle valve, the intake air amount Qa from an air flow meter (not shown) attached to the intake pipe, and the temperature sensor (not shown) attached to the intake pipe The intake air temperature Ta can also be mentioned. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 through an output port. The signals output from the engine ECU 24 include, for example, a drive control signal to a throttle motor that adjusts the position of a throttle valve, a drive control signal to a fuel injection valve, and a drive control signal to an ignition coil integrated with an igniter. can be mentioned. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotational speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 23 .

The planetary gear 30 is configured as a single pinion planetary gear mechanism. The sun gear of the planetary gear 30 is connected to the rotor of the motor MG1. A ring gear of the planetary gear 30 is connected to a drive shaft 36 that is connected to drive wheels 39a and 39b via a differential gear 38. As shown in FIG. A crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30 via a damper 28 .

The motor MG1 is configured as, for example, a synchronous generator-motor, and the rotor is connected to the sun gear of the planetary gear 30 as described above. The motor MG2 is configured as, for example, a synchronous generator-motor, and has a rotor connected to the drive shaft 36 . Inverters 41 , 42 are connected to motors MG<b>1 , MG<b>2 and are connected to battery 50 via power line 54 . The motors MG1 and MG2 are rotationally driven by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as a “motor ECU”) 40 .

Although not shown, the motor ECU 40 is configured as a microprocessor centering on a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. . The motor ECU 40 receives signals from various sensors necessary to drive and control the motors MG1 and MG2, such as rotational position θm1 from rotational position detection sensors 43 and 44 for detecting the rotational positions of the rotors of the motors MG1 and MG2. , .theta.m2 and phase currents from current sensors for detecting the currents flowing in the respective phases of the motors MG1 and MG2 are inputted via the input ports. The motor ECU 40 outputs switching control signals to a plurality of switching elements (not shown) of the inverters 41 and 42 through output ports. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on the rotational positions .theta.m1 and .theta.m2 of the rotors of the motors MG1 and MG2 from the rotational position detection sensors 43 and 44, respectively.

The battery 50 is configured as, for example, a lithium-ion secondary battery or a nickel-hydrogen secondary battery, and is connected to the inverters 41 and 42 via a power line 54 . The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52 .

Although not shown, the battery ECU 52 is configured as a microprocessor centering on a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. . Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 through an input port. Signals input to the battery ECU 52 include, for example, the voltage Vb of the battery 50 from the voltage sensor 51a installed between the terminals of the battery 50 and the current of the battery 50 from the current sensor 51b attached to the output terminal of the battery 50. Ib, the temperature Tb of the battery 50 from the temperature sensor 51c attached to the battery 50 can be mentioned. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the power storage ratio SOC based on the integrated value of the current Ib of the battery 50 from the current sensor 51b, and performs input/output based on the calculated power storage ratio SOC and the temperature Tb of the battery 50 from the temperature sensor 51c. Limits Win and Wout are calculated. The power storage ratio SOC is the ratio of the amount of electric power that can be discharged from the battery 50 to the total capacity of the battery 50 . The input/output limits Win, Wout are the allowable charge/discharge power with which the battery 50 may be charged/discharged.

Battery ECU 52 sets input/output limits Win and Wout of battery 50 by the following method. As for the input limit Win, first, a basic value Winb (negative value) of the input limit Win is set based on the temperature Tb of the battery 50, and an input limit correction coefficient (positive value ) is set, and the set basic value Winb is multiplied by the input limit correction coefficient to set the normal input limit Winn (negative value). Then, the larger value (as an absolute value) of the set normal input limit Winn and the protection input limit Winp (negative value) as the maximum value of the power allowed to be input to the inverter 41 from the viewpoint of protecting the inverter 41 is the smaller value) to the input limit Win. Regarding output limit Wout, first, a base value Woutb (positive value) of output limit Wout is set based on temperature Tb of battery 50, and an output limit correction coefficient (positive value ) is set, and the set basic value Woutb is multiplied by the output limit correction coefficient (positive value) to set the normal output limit Woutn (positive value). Then, the smaller value of the set normal output limit Woutn and the protective output limit Woutp (positive value) as the maximum value of the power that is allowed to be output from the inverter 42 from the viewpoint of protecting the inverter 42 is used as the output limit. Set to Wout. FIG. 2 shows an example of the relationship between the temperature Tb of the battery 50 and the basic values Winb and Woutb, and FIG. 3 shows an example of the relationship between the charge ratio SOC of the battery 50 and the input/output limit correction coefficient.

Although not shown, the HVECU 70 is configured as a microprocessor centering on a CPU, and in addition to the CPU, has a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. Signals from various sensors are input to the HVECU 70 through input ports. Signals input to the HVECU 70 include, for example, an ignition signal from an ignition switch 80 and a shift position SP from a shift position sensor 82 that detects the operating position of a shift lever 81 . Further, the accelerator opening Acc from an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83, the brake pedal position BP from a brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, and the vehicle speed sensor 88. Vehicle speed V can also be mentioned. The HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via communication ports, as described above.

The hybrid vehicle 20 of the embodiment configured in this way can be driven in a hybrid driving mode (HV driving mode) in which the engine 22 is operated and in an electric driving mode (EV driving mode) in which the engine 22 is stopped. The engine 22 and the motors MG1 and MG2 are controlled so as to run.

Next, the operation of the hybrid vehicle 20 of the embodiment thus configured will be described. 4 and 5 are flowcharts showing an example of a drive control routine executed by the HVECU 70 of the hybrid vehicle 20 of the embodiment. This routine is repeatedly executed every predetermined time (for example, every several milliseconds).

When this routine is executed, the CPU of the HVECU 70 first detects the accelerator opening Acc from the accelerator pedal 83, the vehicle speed V from the vehicle speed sensor 88, the rotational speed Ne of the engine 22 from the engine ECU 24, the motor MG1 from the motor ECU 40, and the speed V from the vehicle speed sensor 88. In addition, data required for control such as rotational speeds Nm1 and Nm2 of motor MG2 and input/output limits Win and Wout from battery ECU 52 are input (step S100).

Subsequently, the required torque Tr* required for the drive shaft 36 is set based on the accelerator opening Acc and the vehicle speed V, and the required power Pe* to be output by the engine 22 is set (step S110). In the embodiment, the required torque Tr* is set by determining in advance the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr* and storing it in the ROM as a required torque setting map. When V is given, the corresponding required torque Tr* is derived from the required torque setting map and set. FIG. 6 shows an example of the required torque setting map. In the embodiment, the required power Pe* of the engine 22 is set by multiplying the set required torque Tr* by the rotation speed Nd of the drive shaft 36 (the rotation speed Nm2 of the motor MG2), which is required for running (the drive shaft 36 The required charge/discharge power Pb* (a positive value when the battery 50 is discharged) based on the charge/discharge ratio SOC of the battery 50 is subtracted from the required power Pd* to obtain the power required for the vehicle. The required power Pe* (required for the engine 22) is calculated.

When the required torque Tr* and the required power Pe* are set, the point at which the engine 22 can be operated efficiently among the operation points (points determined from the torque and the rotation speed) of the engine 22 that can output the set required power Pe* is determined. 22 are set as the target torque Te* and the target rotation speed Ne* (step S120).

Then, the torque command for the motor MG1 (previous Tm1*) and the gear ratio of the planetary gear 30 (the number of teeth of the sun gear 31/the number of teeth of the ring gear 32) set in the process of step S170 described later when this routine was executed last time are is used to calculate the output torque Teest as the torque estimated to be output from the engine 22 according to the following equation (1) (step S130).

Teeth=(1+ρ)・previous Tm1*/ρ (1)

Next, using the target rotation speed Ne* of the engine 22, the rotation speed Nm2 of the motor MG2, and the gear ratio ρ of the planetary gear 30, the target rotation speed Nm1* of the motor MG1 is calculated by Equation (2), and the calculated motor MG1 , the target rotation speed Nm1* of the motor MG1, the rotation speed Nm1 of the motor MG1 input in step S100, the output torque Teest of the engine 22 set in step S130, and the gear ratio ρ of the planetary gear 30, the torque A provisional torque Tm1tmp is calculated as a provisional value of the command Tm1* (step S140). Equation (3) is a relational expression in feedback control for rotating the motor MG1 at the target rotation speed Nm1* (rotating the engine 22 at the target rotation speed Ne*). is a feedforward term, and the second and third terms on the right side are proportional and integral terms of feedback. The first term on the right side can be easily derived using a collinear chart. Also, "k1" in the second term on the right side is the gain of the proportional term, and "k2" in the third term on the right side is the gain of the integral term.

Nm1*=Ne*・(1+ρ)/ρ-Nm2・ρ(2)
Tm1tmp=-ρ・Teach/(1+ρ)+k1・(Nm1*-Nm1)+k2・∫(Nm1*-Nm1)dt (3)

Subsequently, as shown in the following equation (4), the torque command Tm1* for the motor MG1 divided by the gear ratio ρ of the planetary gear 30 is added to the required torque Tr* to obtain a provisional torque command Tm2* for the motor MG2. is calculated as a provisional torque Tm2tmp (step S150).

Tm2tmp=Tr*+Tm1*/rho (4)

Then, torque limits Tm1min and Tm1max are set as the upper and lower limits of the torque that may be output from the motor MG1 that satisfy both the following equations (5) and (6) (step S160). Here, equation (5) is a relationship in which the sum of the torques output from the motors MG1 and MG2 to the ring gear shaft 32a is within the range from 0 to the required torque Tr*, and equation (6) is: The relationship is such that the sum of the power input/output by the motors MG1 and MG2 is within the range of the input/output limits Win and Wout of the battery 50 . FIG. 7 is an explanatory diagram showing an example of torque limits Tm1min and Tm1max of the motor MG1. The torque limits Tm1min and Tm1max can be obtained as the maximum and minimum values of the provisional torque Tm1tmp in the shaded area in the drawing. As can be seen from FIG. 7, when the required torque Tr* is a positive value, the sum of the torques output from the motors MG1 and MG2 to the drive shaft 36 is the required torque Tr*, and the relationship between the motor MG1 and the motor MG2 The driving point of the motor MG1 that satisfies the relation that the sum of the electric power input and output by and is the input limit Win of the battery 50 is set to the torque limit Tm1min. That is, the torque limit Tm1min is calculated by the equation (7) obtained from the equations (5) and (6). Further, the sum of the torques output from the motors MG1 and MG2 to the drive shaft 36 is 0, and the sum of the power input/output from the motors MG1 and MG2 is the output limit Wout of the battery 50. and the drive point of the motor MG1 that satisfies the above relationship is set to the torque limit Tm1max. That is, the torque limit Tm1max is calculated by the formula (8) obtained from the formulas (5) and (6).

0≦-Tm1tmp/ρ+Tm2tmp≦Tr* (5)
Win≦Tm1tmp・Nm1+Tm2tmp・Nm2≦Wout (6)
Tm1min=(Win-Tr*Nm2)/(Nm1+Nm2/ρ) (7)
Tm1max=Wout/Nm1r+Nm2/ρ (8)

When the torque limits Tm1min and Tm1max are set in this manner, the smaller one of the provisional torque Tm1tmp of the motor MG1 and the torque limit Tm1max and the torque limit Tm1min, whichever is larger, are obtained as shown in the following equation (9). (The provisional torque Tm1tmp of the motor MG1 is limited by the torque limits Tm1min and Tm1max to set the torque command Tm1* of the motor MG1) (step S170).

Tm1*=max(min(Tm1tmp,Tm1max),Tm1min) (9)

Subsequently, the target power Pm1 to be output from the motor MG1 is calculated from the product of the calculated torque command Tm1* for the motor MG1 and the rotational speed Nm1 of the motor MG1 input at step S100 (step S180).

Subsequently, it is determined whether or not the vehicle speed V input in step S100 is equal to or lower than a predetermined vehicle speed Vref (step S190). The predetermined vehicle speed Vref is a vehicle speed predetermined as a threshold value for determining whether or not there is a high possibility that the vehicle will stop.

When the vehicle speed V exceeds the predetermined vehicle speed Vref in step S190, it is determined that the possibility of the vehicle stopping is not high, and the output of the motor MG1 is reduced from the output limit Wout and the input limit Win of the battery 50, and the output of the motor MG2 is reduced. The hysteresis width His used for setting the output of the motor MG1 (hereinafter referred to as a temporary power (temporary output power) Pm1his of the motor MG1) when setting the output limit of the motor MG1 is set to a predetermined width ΔWmax (step S200 ). The predetermined width ΔWmax is a value determined in advance by experiment or analysis as a constant value in consideration of suppressing frequent changes in the permissible output range P2 of the motor MG2, which will be described later.

After setting the hysteresis width His, the temporary power Pm1his of the motor MG1 is calculated using the following equation (10) based on the set hysteresis width His (step S220). In equation (10), "previous Pm1his" is the tentative power of motor MG1 calculated in step S230 of the previous routine.

Pm1his=min(max(previous Pm1his,Pm1-His),Pm1+His) (10)

FIG. 8 shows how the temporary power Pm1his of the motor MG1 is set. In the figure, the solid line indicates the target power Pm1 of the motor MG1, and the dashed line indicates the tentative power Pm1his of the motor MG1. As shown in FIG. 8 and equation (10), when the previous tentative power of the motor MG1 (previous Pm1his) is within the range of the hysteresis width His around the target power Pm1 of the motor MG1, the previous tentative power is The temporary power Pm1his of the motor MG1 is set, and if the previous temporary power is not within the range of the hysteresis width His, the temporary power Pm1his of the motor MG1 is changed so as to be within the range. The provisional power Pm1his of the motor MG1 is directly reflected in the setting of the allowable output range P2 of the motor MG2, which is the output limit of the motor MG2, which will be described later. can be prevented from being frequently changed in the permissible output range P2 of the motor MG2.

When the provisional power Pm1his of the motor MG1 is set in this way, the set provisional power Pm1his is subtracted from the output limit Wout and input limit Win of the battery 50 input in step S100 to obtain the output lower limit value and output upper limit value of the motor MG2. The allowable output range P2 is calculated and set (step S230), and the torque limits Tm2min and Tm2max of the motor MG2 are obtained by dividing the output lower limit value and output lower limit value of the motor MG2 in the allowable output range P2 by the rotation speed Nm2 of the motor MG2. and are calculated (step S240).

Then, the smaller value of the torque limit Tm2max and the larger one of the provisional torque Tm2tmp and the torque limit Tm2min set in step S150 is set as the torque command Tm2* (the provisional torque Tm2tmp is set to the torque limit). The value limited by Tm2min and Tm2max is set as the torque command Tm2* (step S250). Then, the target torque Te* of the engine 22 is transmitted to the engine ECU 24, and the torque commands Tm1* and Tm2* of the motors MG1 and MG2 are transmitted to the motor ECU 40 (step S260), and this routine ends. Upon receiving the target torque Te*, the engine ECU 24 performs controls such as ignition control and fuel injection control so that the engine 22 outputs a torque corresponding to the target torque Te*. Upon receiving the torque commands Tm1* and Tm2*, the motor ECU 40 controls the switching elements of the inverters 41 and 42 so that the torque corresponding to the torque command Tm1* is output from the motor MG1 and the torque corresponding to the torque command Tm2* is output from the motor MG2. switching control. In this way, when the vehicle speed V exceeds the predetermined vehicle speed Vref, setting the hysteresis width His to the predetermined width ΔWmax suppresses frequent changes in the allowable output range P2 of the motor MG2, and reduces the temporary power Pm1his of the motor MG1. Frequent changes are suppressed, and frequent changes of the torque limit Tm2min and the torque limit Tm2max are suppressed. As a result, frequent changes in the torque command Tm2* are suppressed, and vibration of the vehicle due to fluctuations in the torque output from the motor MG2 can be suppressed.

When the vehicle speed V is equal to or lower than the predetermined vehicle speed Vref in step S190, it is determined that the vehicle is highly likely to stop, and the input/output difference |Wout-Win| as the absolute value of the output limit Wout minus the input limit Win. is set as the hysteresis width His (step S210), and the provisional power Pm1his of the motor MG1 is set using the set hysteresis width His (step S220). Using the temporary power Pm1his thus set, the permissible output range P2 of the motor MG2 is calculated (step 230), and the torque limit Tm2min and the torque limit Tm2max are set so that the power output from the motor MG2 is within the permissible output range P2. Then (step S240), the provisional torque Tm2tmp is limited by the torque limit Tm2min and the torque limit Tm2max, and the torque is set to the torque command Tm2* (step S250). It is transmitted (step S260), and this routine ends.

is set to the hysteresis width His in step S210, the hysteresis width His is within a range not less than 0, and the smaller the output limit Wout and the larger the input limit Win (input The smaller the absolute value of the limit Win, the narrower it is set. The narrower the hysteresis width His is set, the closer the temporary power Pm1his of the motor MG1 is set to the target power Pm1 of the motor MG1. becomes smaller, the temporary power Pm1his is set to a value close to the target power Pm1 of the motor MG1. Therefore, the temporary power Pm1his becomes excessively large with respect to the target power Pm1 of the motor MG1, and the upper limit value (=Wout-Pm1his) of the allowable output range P2 of the motor MG2 becomes too small. Tm2* is prevented from being set too small. This can prevent the motor MG<b>2 from outputting the desired torque, and can prevent the drive shaft 36 from outputting the desired torque (required torque Tr*). Therefore, it is possible to prevent a situation in which the torque that can be output from the motor MG2 becomes small and the vehicle cannot start moving after it stops. Further, since the hysteresis width His is set to the input/output difference |Wout−Win|, the hysteresis width His can be set wider than the value 0 when the output limit Wout is 0 and the input limit Win is not 0. As the hysteresis width His is set wider, frequent changes in the temporary power Pm1his of the motor MG1 are suppressed, and frequent changes in the torque command Tm2* of the motor MG2 are suppressed. As a result, fluctuations in the torque output from the motor MG2 can be suppressed, and vibration of the vehicle can be suppressed. Therefore, it is possible to suppress the inability to output the desired torque to the drive shaft 36 while suppressing the vibration of the vehicle.

According to the hybrid vehicle 20 of the embodiment described above, when the vehicle speed V is equal to or lower than the predetermined vehicle speed Vref, the temporary power of the first motor is kept constant within the range of the hysteresis width His centered on the target power Pm1 of the motor MG1. Power Pm1his (provisional output power) is set, and within the allowable output range P2 of the motor MG2 (within the power limit value of the motor MG2) based on the set provisional power Pm1his and the input limit Win and output limit Wout of the battery. and the hysteresis width His is set to the input/output difference |Wout-Win| between the output limit Wout and the input limit Win of the battery 50. While suppressing vibration, it is possible to suppress the inability to output a desired torque to the drive shaft 36 .

In the hybrid vehicle 20 of the embodiment, the hysteresis width His is set to the input/output difference |Wout-Win|. However, when the input/output difference |Wout-Win| is small, the hysteresis width His may be set to be smaller than when it is large. It may be set to a value multiplied by a predetermined coefficient. Further, the hysteresis width His may be set based on the input/output difference |Wout-Win|. For example, the input/output difference |Wout-Win| It may be set to the smaller value of the maximum value. In this way, excessive vibration of the vehicle can be suppressed.

In the hybrid vehicle 20 of the embodiment, the battery ECU 52 sets the input/output limits Win and Wout of the battery 50 . However, input/output limits Win and Wout may be set by other electronic control units such as motor ECU 40 and HVECU 70, or may be set by a plurality of electronic control units (for example, motor ECU 40 and HVECU 70).

In the hybrid vehicle 20 of the embodiment, the battery 50 is used as the power storage device, but a capacitor may be used.

Although the hybrid vehicle 20 of the embodiment includes the engine ECU 24, the motor ECU 40, the battery ECU 52, and the HVECU 70, at least some of these may be configured as a single electronic control unit.

In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is output to the drive shaft 36, but the power of the motor MG2 is output to the axle to which the drive shaft 36 is connected (the axle to which the drive wheels 39a and 39b are connected). may be connected to different axles.

The correspondence relationship between the main elements of the embodiments and the main elements of the invention described in the column of Means for Solving the Problems will be described. In the embodiment, the motor ECU 40, the battery ECU 52, and the HVECU 70 correspond to a "hybrid vehicle control device".

Note that the correspondence relationship between the main elements of the examples and the main elements of the invention described in the column of Means for Solving the Problems is the Since it is an example for specifically explaining the mode for solving the problem, it does not limit the elements of the invention described in the column of the means for solving the problem. That is, the interpretation of the invention described in the column of Means to Solve the Problem should be made based on the description in that column, and the Examples are based on the description of the invention described in the column of Means to Solve the Problem. This is only a specific example.

Although the embodiments for carrying out the present invention have been described above, the present invention is not limited to such embodiments at all, and can be modified in various forms without departing from the scope of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICABILITY The present invention is applicable to the manufacturing industry of control devices for hybrid vehicles.

20 hybrid vehicle, 22 engine, 23 crank position sensor, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 planetary gear, 36 drive shaft, 38 differential gear, 39a, 39b drive wheels, 40 motor Electronic control unit (motor ECU) 41, 42 inverter 43, 44 rotational position detection sensor 50 battery 51a voltage sensor 51b current sensor 51c temperature sensor 52 battery electronic control unit (battery ECU) 54 power line , 70 hybrid electronic control unit (HVECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, MG1, MG2 motor.

Claims (5)

an engine, a first motor, a planetary gear in which three rotating elements are connected to a rotary shaft of the first motor, an output shaft of the engine, and a drive shaft coupled to drive wheels; A control device for a hybrid vehicle that includes a connected second motor and a battery that exchanges electric power with the first and second motors, and is mounted on the hybrid vehicle to control the engine and the first and second motors. There is
When the vehicle speed is equal to or lower than a predetermined vehicle speed, the provisional output power of the first motor is set so as to be constant within a range of hysteresis width centered on the target power to be output from the first motor, and the set provisional output power is set. controlling the second motor so that the second motor is driven within a power limit value range of the second motor based on the power and the output limit of the battery;
A control device for a hybrid vehicle, wherein the hysteresis width is set based on an input/output difference as a difference between the output limit and the input limit of the battery. A control device for a hybrid vehicle according to claim 1,
A control device for a hybrid vehicle, wherein the hysteresis width is set to be smaller when the input/output difference is small than when the input/output difference is large. A control device for a hybrid vehicle according to claim 2,
A control device for a hybrid vehicle that sets the hysteresis width to the input/output difference. A control device for a hybrid vehicle according to claim 2,
A control device for a hybrid vehicle, wherein the hysteresis width is set to a value obtained by multiplying the input/output difference by a predetermined coefficient that is a positive value. A control device for a hybrid vehicle according to claim 1,
A control device for a hybrid vehicle, wherein the hysteresis width is set to the smaller one of the input/output difference and the maximum value of the input/output difference that allows vibration of the vehicle.

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