JP2013216264A - Power generation control apparatus for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generation control apparatus for a hybrid vehicle capable of satisfying required driving force of an electric motor while maintaining a residual capacity of a storage battery.SOLUTION: A control apparatus 29 determines whether electric power generation of an electric generator 13 is to be performed in accordance with a state of a storage battery 11, and when power generation is permitted, a power generation amount equivalent to an output required for cruising is set, depending on a traveling state, and an additional power generation amount is also set in accordance with a required electric power amount depending on a vehicle state and the traveling state, and an internal combustion engine 12 and the electric generator 13 are controlled on the basis of the power generation amount and the additional power generation amount. The electric power covering the output required for cruising of the vehicle is covered by the power generation amount by the electric motor 13, and the electric power required to perform temporary acceleration or EV traveling of the vehicle is covered by the electric power of the storage battery 11 while a predetermined margin is complemented with the additional power generation amount, and thereby, the internal combustion engine 12 is miniaturized and driving is performed in the vicinity of the best fuel consumption point. Therefore, improvement of fuel economy and reduction of COemission amount and noise of the internal combustion engine 12 can be achieved, and the required residual capacity can be secured.

Description

  The present invention relates to a power generation control device for a hybrid vehicle that includes a generator driven by an internal combustion engine, a storage battery that stores electric power generated by the generator, and a control device that controls the internal combustion engine and the generator.

  A series hybrid that performs an EV traveling mode in which an electric motor is driven only by electric power stored in a storage battery and a series traveling mode in which the electric motor is driven by electric power generated by a generator driven by an internal combustion engine. In automobiles, the determination of the start of the internal combustion engine that drives the generator and the amount of power generated by the generator are determined based on the required driving force of the motor derived from the vehicle speed, the accelerator pedal opening degree, etc. and the remaining capacity of the storage battery. This is known from Patent Document 1 below.

  Further, in a parallel hybrid vehicle having two power sources of an internal combustion engine and an electric motor, it is possible to travel by the internal combustion engine alone, travel by the electric motor alone, and travel by both the internal combustion engine and the electric motor. Japanese Patent Application Laid-Open No. 2004-260260 discloses a battery that is operated at a constant rotational speed at the fuel economy best point where the fuel efficiency is basically the best, and when the output of the internal combustion engine has a surplus, generates power with the surplus output and charges the storage battery. It is.

WO2011 / 078189 JP 09-224304 A

  By the way, in a plug-in type hybrid vehicle, EV traveling that travels with the electric power stored in the storage battery is fundamental, and only when the remaining capacity of the storage battery decreases, the generator is driven by the internal combustion engine to charge the storage battery. The frequency with which the generator operates is inevitably smaller than that of a hybrid vehicle other than the plug-in type. Therefore, in a plug-in type hybrid vehicle, it is desirable to use an internal combustion engine that drives a generator that is small and has a small displacement.

  The one described in Patent Document 1 performs so-called “required output follow-up power generation control”, and determines the necessity of driving the internal combustion engine and the power generation amount of the generator from the required driving force of the motor and the remaining capacity of the storage battery. However, the series type hybrid vehicle equipped with a relatively small internal combustion engine in recent years has a required driving force of an electric motor compared to a conventional series type hybrid vehicle equipped with a relatively large internal combustion engine. If it is large, the rotational speed of the internal combustion engine will increase, which will greatly deviate from the fuel efficiency best point, and not only will the fuel efficiency of the series travel significantly deteriorate, but also the vibration and noise will increase due to the increase in the rotational speed of the internal combustion engine. May increase.

  In addition, what is described in Patent Document 2 performs so-called “fixed-point operation type power generation control”, and operates an internal combustion engine at the best fuel efficiency during series travel. In series-type hybrid vehicles equipped with an internal combustion engine, the amount of power generated by the generator driven by the internal combustion engine cannot meet the required driving force of the motor, and the storage battery tends to discharge, making it difficult to maintain energy. there is a possibility.

  The present invention has been made in view of the above-described circumstances, and compensates for the weak points of “required output follow-up type power generation control” and “fixed point operation type power generation control”, while maintaining the remaining capacity of the storage battery by power generation by a small internal combustion engine. An object of the present invention is to provide a power generation control device for a hybrid vehicle that can satisfy the required driving force of an electric motor.

  In order to achieve the above object, according to an invention described in claim 1, a generator driven by an internal combustion engine, a storage battery storing electric power generated by the generator, the internal combustion engine and the generator are provided. A control device for controlling, the control device determines whether or not the generator can generate power according to the state of the storage battery, and when power generation is permitted, A power generation amount is set, an additional power generation amount is set according to the amount of power required depending on the vehicle state and the traveling state, and the internal combustion engine and the generator are controlled based on the power generation amount and the additional power generation amount. A power generation control device for a hybrid vehicle is proposed.

  According to a second aspect of the invention, in addition to the configuration of the first aspect, the control device determines whether or not power generation is possible based on the depth of discharge of the storage battery. A control device is proposed.

  According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the control device determines whether or not power generation is possible based on a remaining capacity of the storage battery. A power generation control device for a hybrid vehicle is proposed.

  According to a fourth aspect of the present invention, in addition to the configuration of any one of the first to third aspects, the control device sets the power generation amount based on a vehicle speed. A power generation control device for a hybrid vehicle is proposed.

  According to the invention described in claim 5, in addition to the configuration of claim 4, the control device derives the rolling resistance and the air resistance during traveling based on the vehicle speed, and the derived rolling resistance and air resistance. A power generation control device for a hybrid vehicle is proposed in which the power generation amount is set based on the above.

  According to the invention described in claim 6, in addition to the configuration of any one of claims 1 to 5, the control device sets the additional power generation amount based on a road surface gradient estimated value. A power generation control device for a hybrid vehicle is proposed.

  According to the invention described in claim 7, in addition to the configuration of any one of claims 1 to 6, the control device sets the additional power generation amount based on the discharge depth of the storage battery. A power generation control device for a hybrid vehicle is proposed.

  According to the invention described in claim 8, in addition to the configuration of any one of claims 1 to 7, the control device sets the additional power generation amount based on the remaining capacity of the storage battery. A power generation control device for a hybrid vehicle is proposed.

  According to the invention described in claim 9, in addition to the configuration of any one of claims 1 to 8, the control device sets the additional power generation amount based on a vehicle speed. A power generation control device for a hybrid vehicle is proposed.

  According to the invention described in claim 10, in addition to the configuration of any one of claims 1 to 9, an air conditioner that air-conditions the vehicle interior is provided, and the control device includes the air conditioner of the air conditioner. Proposed is a power generation control device for a hybrid vehicle that determines whether operation is possible and sets the additional power generation amount according to the required temperature when the air conditioner is operating.

  According to an eleventh aspect of the invention, in addition to the configuration of any one of the first to tenth aspects, the control device corrects the added power generation amount according to a vehicle speed. A power generation control device for a hybrid vehicle is proposed.

  According to a twelfth aspect of the present invention, in addition to the configuration of any one of the first to eleventh aspects, the control device rotates the internal combustion engine from the power generation amount and the additional power generation amount. A power generation control device for a hybrid vehicle characterized by setting the number is proposed.

  According to a thirteenth aspect of the present invention, a generator driven by an internal combustion engine, a storage battery that stores electric power generated by the generator, an air conditioner that air-conditions a vehicle interior, the air conditioner, and the internal combustion engine An engine and a control device for controlling the power generator, the control device determines whether or not power generation is possible based on at least one parameter of a discharge depth and a remaining capacity of the storage battery, and permits power generation , Deriving at least one of air resistance and rolling resistance during traveling based on the vehicle speed, setting the power generation amount corresponding to the output required for the cruise based on the derived resistance, and estimating the vehicle gradient, Based on at least one parameter of the discharge depth of the storage battery, the remaining capacity of the storage battery, the vehicle speed, and the required temperature of the air conditioner, an additional power generation amount is set and set. Power generation control apparatus for a hybrid vehicle is proposed, which comprises setting the rotational speed of the internal combustion engine from coulometric and the plus power generation.

  The electric compressor 15 and the electric heater 16 of the embodiment correspond to the air conditioner of the present invention, and the cruise output PGENRL at each vehicle speed of the embodiment corresponds to the power generation amount of the present invention, and at each vehicle speed of the embodiment. The additional power generation amount PGENBASE corresponds to the additional power generation amount of the present invention.

According to the configuration of claim 1, a power generation control device for a hybrid vehicle includes a generator driven by an internal combustion engine, a storage battery that stores electric power generated by the generator, and a control device that controls the internal combustion engine and the generator. Prepare. The control device determines whether or not the generator can generate power according to the state of the storage battery, and when generating power, sets the amount of power generation that can cover the output necessary for the cruise according to the running state, and the vehicle The additional power generation amount is set according to the current or future power amount according to the state and running state, and the internal combustion engine and the generator are controlled based on the power generation amount and the additional power generation amount. The amount of power that can be used to cover the output is covered by the amount of power generated by the generator, and the amount of power required for temporary acceleration or EV driving of the vehicle is supplemented by the amount of power generated by adding a certain margin. it is to cover, to enable to be operated in the vicinity of the fuel best point while miniaturizing the internal combustion engine, a reduction in fuel consumption, reduction of CO ₂ emissions, as well as achieving a reduction in noise of the internal combustion engine, the storage battery is release Prevented from tends can be ensured remaining capacity required. In addition, since the amount of power generation that can cover the output necessary for the cruise is set according to the running state, it becomes possible to charge the storage battery with the surplus output of the generator during downhill or deceleration, reducing the efficiency of the internal combustion engine Without generating such a large output, the remaining capacity of the storage battery can be ensured by increasing the power generation frequency of the generator.

  According to the second aspect of the present invention, whether or not power generation is possible is determined based on the depth of discharge of the storage battery. Therefore, when the remaining capacity of the storage battery is insufficient, EV traveling can be prohibited and overdischarge can be prevented.

  Further, according to the configuration of the third aspect, since it is determined whether or not power generation is possible based on the remaining capacity of the storage battery, when the remaining capacity of the storage battery is insufficient, EV traveling can be prohibited to prevent overdischarge.

  According to the fourth aspect of the present invention, since the power generation amount is set based on the vehicle speed, the power generation amount that can cover the output required for the cruise that increases as the vehicle speed increases is secured by the power generation amount of the generator. be able to.

  According to the fifth aspect of the present invention, the rolling resistance and air resistance at the time of traveling are derived based on the vehicle speed, and the power generation amount is set based on the derived rolling resistance and air resistance. The amount of power generation that can be performed can be set with high accuracy.

  According to the configuration of the sixth aspect, since the additional power generation amount is set on the basis of the road surface gradient estimated value, the power generation amount capable of supplying the output required for the cruise that varies depending on the road surface gradient estimated value is generated. Can be ensured by.

  Further, according to the configuration of the seventh aspect, since the additional power generation amount is set based on the discharge depth of the storage battery, the fuel consumption of the internal combustion engine can be further reduced by suppressing the additional power generation amount to the necessary minimum.

  According to the configuration of the eighth aspect, since the control device sets the additional power generation amount based on the remaining capacity of the storage battery, the fuel consumption of the internal combustion engine can be further reduced by minimizing the additional power generation amount. .

  According to the ninth aspect of the present invention, since the control device sets the additional power generation amount based on the vehicle speed, the fuel consumption of the internal combustion engine can be further reduced by minimizing the additional power generation amount. In addition, since it is possible to determine whether or not excessive power generation is possible from the vehicle speed, that is, it is possible to generate excessive power in the optimal vehicle speed range, so power generation due to vibration at low speed or excessive operation at high speed is possible. It can suppress and can improve merchantability.

  Further, according to the configuration of the tenth aspect, whether or not the air conditioner can be operated is determined, and when the air conditioner is operating, the additional power generation amount is set based on the required temperature, so the power consumption of the air conditioner is added. It can be covered by power generation.

  Further, according to the configuration of the eleventh aspect, the amount of power generation added is corrected according to the vehicle speed, so that the amount of power generation that can cover the output required for the cruise that changes depending on the vehicle speed can be secured by the generator.

  According to the twelfth aspect of the present invention, since the rotational speed of the internal combustion engine is set from the power generation amount and the additional power generation amount, it is possible to cause the generator to generate power corresponding to the power generation amount and the additional power generation amount.

According to the configuration of claim 13, the control device determines whether or not the generator can generate power according to the state of the storage battery, and sets the power generation amount necessary for the cruise output according to the vehicle speed when the power generation is permitted. In addition, an additional power generation amount is set according to the amount of electric power required depending on the vehicle state and the traveling state, and the internal combustion engine and the generator are controlled based on the power generation amount and the additional power generation amount. The amount of power generated by the generator is used to provide sufficient power to cover the output, and the power required by the storage battery is used to temporarily accelerate the vehicle or perform EV travel while supplementing the power generation amount with a predetermined margin. This makes it possible to reduce the size of the internal combustion engine while driving near the best fuel efficiency, reduce fuel consumption, reduce CO ₂ emissions, and reduce noise of the internal combustion engine. In It is possible to secure the remaining capacity necessary to prevent the that. In addition, since the amount of power generation required for the cruise output is set according to the traveling state, it becomes possible to charge the storage battery with the surplus output of the generator when going downhill or decelerating, and the large output that reduces the efficiency of the internal combustion engine The remaining capacity of the storage battery can be secured by increasing the power generation frequency of the generator without generating power.

The block diagram which shows the whole structure of the power unit of a hybrid vehicle. The flowchart of an operation determination routine. The flowchart of a discharge depth calculation routine. 7 is a flowchart of a power generation execution determination routine. The flowchart of an electric power generation amount calculation routine. Explanatory drawing of the calculation method of the depth of discharge.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  A hybrid vehicle equipped with a storage battery 11 such as a lithium ion (Li-ion) type is a series hybrid vehicle in which a generator 13 is connected to a crankshaft of an internal combustion engine 12 and a motor 14 for traveling is connected to drive wheels. It is. The storage battery 11 includes an external charging plug 15 that can be connected to an external charging device (not shown), for example, and can be charged by the external charging device 16 through the external charging plug 15.

  The motor 13 and the generator 14 are, for example, three-phase DC brushless type, and the generator 13 is connected to the first power drive unit 17 and the motor 14 is connected to the second power drive unit 18. The first and second power drive units 17 and 18 include a PWM inverter by pulse width modulation (PWM) having a bridge circuit formed by bridge connection using a plurality of switching elements such as transistors, for example, and the first converter It is connected to the storage battery 11 via 19.

  For example, when the generator 13 generates power using the power of the internal combustion engine 12, the AC power generated from the generator 13 is converted into DC power by the first power drive unit 17 and then converted by the first converter 19. Then, the storage battery 11 is charged, or the second power drive unit 18 converts it into AC power again to supply power to the motor 14. For example, when the electric motor 14 is driven, the DC power output from the storage battery 11 or the DC power output from the generator 13 and converted by the second power drive unit 17 is converted to AC power by the second power drive unit 18. The electric motor 14 is supplied.

  On the other hand, for example, when the driving force is transmitted from the driving wheel side to the motor 14 side during deceleration of the hybrid vehicle, the motor 14 functions as a generator to generate a so-called regenerative braking force, and the kinetic energy of the vehicle body is converted into electric energy. As recovered. During power generation by the electric motor 14, the second power drive unit 18 converts AC generated (regenerative) power output from the electric motor 14 into DC power, and further converts the voltage by the first converter 19 to charge the storage battery 11.

  Further, a low-voltage 12V storage battery 20 for driving an electric load composed of various auxiliary machines is connected to the storage battery 11 via a second converter 21, and the second converter 21 is connected to a voltage between terminals of the storage battery 11 or further. The 12V storage battery 20 can be charged by stepping down the voltage across the terminals of the first converter 19 to a predetermined voltage value.

  For example, when the remaining capacity (SOC: State Of Charge) of the storage battery 11 is reduced, the inter-terminal voltage of the 12V storage battery 20 may be boosted by the second converter 21 so that the storage battery 11 can be charged. .

  In addition, an electric compressor 22 and an electric heater 23 that air-condition the passenger compartment are connected to the storage battery 11.

The control device 24 for controlling the power system of the hybrid vehicle includes, for example, a storage battery ECU 25, an internal combustion engine ECU 26, a converter as various ECUs (Electronic Control Units) configured by an electronic circuit such as a CPU (Central Processing Unit). The generator ECU 29 is connected to and controlled by the ECU 27, the motor ECU 28, the generator ECU 29, and the air conditioning ECU 30. The generator ECU 29 controls the power conversion operation of the first power drive unit 17, thereby generating power from the generator 13 by the power of the internal combustion engine 12. Control.

  The electric motor ECU 28 controls the driving and power generation of the electric motor 14 by controlling the power conversion operation of the second power drive unit 18.

  The power conversion operation of the first and second power drive units 17 and 18 is controlled according to a pulse for driving on / off the transistors of the first and second power drive units 17 and 18 by, for example, pulse width modulation (PWM). The operation amounts of the generator 13 and the electric motor 14 are controlled by the duty of this pulse, that is, the on / off ratio.

  The storage battery ECU 25 controls, for example, monitoring and protection of the high-voltage equipment system including the storage battery 11 and controls the power conversion operation of the second converter 21. For example, the storage battery ECU 25 calculates various state quantities such as a remaining capacity (SOC: State Of Charge) based on the detection signals of the inter-terminal voltage, current, and temperature of the storage battery 11. The storage battery ECU 25 is connected to a voltage sensor that detects the voltage of the storage battery 11, a current sensor that detects the current of the storage battery 11, and a temperature sensor that detects the temperature of the storage battery 11, and a detection signal output from these sensors is input. The

  The internal combustion engine ECU 26 controls, for example, fuel supply to the internal combustion engine 12 and ignition timing. For example, the internal combustion engine ECU 26 applies a control current to an electromagnetic actuator that drives the throttle valve, and electronically controls the throttle valve so that the valve opening degree according to an instruction from the storage battery ECU 25 is obtained. Further, when the control is performed following the request output from the driver, the internal combustion engine ECU 26 performs electronic control by supplying a control current to the electromagnetic actuator that drives the throttle valve in accordance with the accelerator pedal opening. Further, the internal combustion engine ECU 26 manages and controls all other ECUs. For this reason, detection signals output from various sensors that detect the state quantity of the hybrid vehicle are input to the internal combustion engine ECU 26.

  The various sensors are, for example, a vehicle speed sensor that detects the vehicle speed, a coolant temperature sensor that detects the coolant temperature of the internal combustion engine 12, an accelerator pedal opening sensor that detects the accelerator pedal opening, and the like.

  Each ECU is connected to a CAN (Controller Area Network) communication first line 31 of the vehicle together with sensors for detecting various states of the hybrid vehicle.

  The electric compressor 22 and the electric heater 23, together with a meter made up of instruments that display various states of the hybrid vehicle, are connected to a CAN (Controller Area Network) having a communication speed slower than the CAN (Controller Area Network) communication first line 31. It is connected to the communication second line 32.

  The internal combustion engine 12, the generator 13, and the first power drive unit 17 constitute an auxiliary power unit 33 that generates electric power with the driving force of the internal combustion engine 12.

  Next, power generation control of the hybrid vehicle having the above configuration will be described.

  The flowchart of FIG. 2 shows an operation determination routine, and six types of operation modes of the hybrid vehicle are determined by this routine.

  First, if the select range selected by the driver in step S1 is the “P” range (parking range) or the “N” range (neutral range), the generator power generation output PREQGEN which is the power generation amount of the generator 13 in step S2. Is set to the generator output PREQGENIDL during idling, and the generator internal combustion engine speed NGEN, which is the rotational speed of the internal combustion engine 12, is set to the generator internal combustion engine speed NGENIDL during idling in step S3. In step S4, if the remaining capacity SOC (State of Charge) of the storage battery 11 is equal to or lower than the idle power generation execution upper limit remaining capacity SOCIDLE, the operation mode is set to the first mode (REV idle mode) in step S5, and the operation determination routine is executed. finish. If the remaining capacity SOC of the storage battery 11 exceeds the idle power generation execution upper limit remaining capacity SOCIDLE in step S4, the operation mode is set to the second mode (idle stop mode) in step S6, and the operation determination routine is terminated.

  The remaining capacity SOC of the storage battery 11 is calculated by integrating the charging / discharging current detected by the current sensor to calculate the accumulated charge amount and the accumulated discharge amount. The accumulated charge amount and the accumulated discharge amount are determined in the initial state or the remaining capacity SOC immediately before the start of charge / discharge. It can be calculated by adding or subtracting to. Further, since the open circuit voltage (OCV) of the storage battery 11 is correlated with the remaining capacity SOC, it is also possible to calculate the remaining capacity SOC from the open voltage OCV.

  In the first mode (REV idle mode), in order to increase the remaining capacity SOC of the storage battery 11, the motor 14 is stopped in the “P” range (parking range) or the “N” range (neutral range). In this mode, idling operation of 12 is performed to cause the generator 13 to generate power, and the storage battery 11 is charged with the generated power of the generator 13.

  In the second mode (idle stop mode), since the remaining capacity SOC of the storage battery 11 is sufficient, the idling stop control of the internal combustion engine 12 is performed with the motor 14 stopped in the “P” range or the “N” range. In this mode, the generator 13 is stopped.

  When the selection range selected by the driver in step S1 is neither the “P” range nor the “N” range, for example, the “D” range (forward travel range) or the “R” range (reverse travel range). When the driver depresses the brake pedal in step S7 and the vehicle speed VP detected by the vehicle speed sensor in step S8 is zero, that is, when the vehicle is stopped, the process proceeds to steps S2 to S4. The first mode in step S5 or the second mode in step S6 is selected.

  If the driver does not step on the brake pedal in step S7 or if the vehicle speed VP is not zero in step S8 even if the driver steps on the brake pedal, for example, the vehicle decelerates for forward or reverse deceleration. If the vehicle speed VP and the accelerator pedal opening AP detected by the accelerator pedal opening sensor are parameters in step S9, the map is searched for the required driving force FREQF requested by the driver to be output to the motor 14.

  In the following step S10, the estimated gradient θ of the road surface on which the vehicle is currently traveling is calculated from the vehicle speed VP, the acceleration α calculated by time differentiation of the vehicle speed VP, and the previous value FREQFB of the required driving force FREQF. The estimated gradient value θ is calculated by equation (1).

θ = [FREQFB− (Ra + Rr + Rc)] / (W * g) (1)
Here, in equation (1), Ra is air resistance, Rr is rolling resistance, Rc is acceleration resistance, W is vehicle weight, and g is gravitational acceleration. Rr is calculated by equation (2), Rc is calculated by equation (3), and Rc is calculated by equation (4).

Ra = λ * S * VP ² (2)
Rr = W * μ (3)
Rc = α * W (4)
In the equations (2) to (4), λ is an air resistance coefficient, S is a front projection area, VP is a vehicle speed, μ is a rolling resistance coefficient, and α is an acceleration.

  In subsequent step S11, the discharge depth DOD of the storage battery 11 is calculated. Details thereof will be described later based on the flowchart of FIG. In subsequent step S12, it is determined whether or not the internal combustion engine 12 is driven to generate power by the generator 13, that is, whether or not power generation by the auxiliary power unit 33 is performed. Details thereof will be described later based on the flowchart of FIG. In subsequent step S14, a generator power generation output PREQGEN, which is a power generation amount by the power generator 13, is calculated. Details thereof will be described later based on the flowchart of FIG.

  In subsequent step S15, the generator internal combustion engine speed NGEN, which is the speed of the internal combustion engine 12 driving the generator 13, is retrieved from the table using the generator power generation output PREQGEN calculated in step S14 as a parameter. Since the generator 13 is connected to and driven by the internal combustion engine 12, the generator internal combustion engine speed NGEN increases as the generator power generation output PREQGEN increases.

  In subsequent step S16, when the required driving force FREQF calculated in step S9 is less than zero, that is, when the electric motor 14 is regenerating, if the power generation execution flag F_GEN = “0” (power generation not performed) in step S17. In step S18, the operation mode is set to the third mode (EV regeneration mode), and the operation determination routine is terminated. If the power generation execution flag F_GEN = “1” (power generation execution) in step S17, the operation mode is set to the fourth mode (REV regeneration mode) in step S19, and the operation determination routine is ended.

  The third mode (EV regeneration mode) is a mode in which the storage battery 11 is charged by causing the electric motor 14 to function as a generator with the driving force reversely transmitted from the driving wheels during deceleration of the vehicle, and the internal combustion engine 12 and the generator 13 are stopped. It is.

  In the fourth mode (REV regeneration mode), the storage battery 11 is charged by causing the motor 14 to function as a generator with the driving force reversely transmitted from the driving wheels when the vehicle is decelerated, and the generator 13 is driven by the internal combustion engine 12. In this mode, the storage battery 11 is charged with the power generated by the generator 13. Thus, not only charging of the storage battery 11 by regenerative power generation of the electric motor 14 but also charging of the storage battery 11 by driving of the auxiliary power unit 33 in parallel when the vehicle is decelerated, charging by regenerative power generation is insufficient. Even in this case, the storage battery 11 can be efficiently charged.

  When the required driving force FREQF is zero or more in step S16, that is, when the motor 14 is driven, if the power generation execution flag F_GEN = “1” (power generation execution) in step S20, the operation mode is changed to the fifth operation mode in step S21. The mode (REV travel mode) is set, and the operation determination routine is terminated. If the power generation execution flag F_GEN = “0” (power generation not performed) in step S20, the operation mode is set to the sixth mode (EV travel mode) in step S22, and the operation determination routine is terminated.

  The fifth mode (REV traveling mode) is a mode in which the electric motor 14 is driven by electric power generated by the auxiliary power unit 33 and / or electric power stored in the storage battery 11, and the internal combustion engine 12, the generator 13, and the electric motor 14 are driven. Are all driven.

  The sixth mode (EV traveling mode) is a mode in which the auxiliary power unit 33 is stopped and the electric motor 14 is driven by the electric power stored in the storage battery 11, and the internal combustion engine 12 and the generator 13 are stopped and the electric motor 14 is stopped. Is driven.

  Next, the discharge depth calculation routine, which is a subroutine of step S11, will be described based on the flowchart of FIG. 3 and the explanatory diagram of FIG.

  First, when the starter switch is turned on in step S101, the remaining capacity SOC at that time is set to the discharge depth calculation reference remaining capacity SOCINT in step S102. In subsequent step S103, it is determined whether or not the discharge depth calculation reference remaining capacity SOCINT is less than the discharge depth calculation reference remaining capacity lower limit SOCINTL, and the discharge depth calculation reference remaining capacity SOCINT is determined to be less than the discharge depth calculation reference remaining capacity lower limit SOCINTL. In step S104, the discharge depth calculation reference remaining capacity lower limit SOCINTL is set to the discharge depth calculation reference remaining capacity SOCINT. When it is determined that the discharge depth calculation reference remaining capacity SOCINT is equal to or greater than the discharge depth calculation reference remaining capacity lower limit SOCINTL, the discharge depth calculation reference remaining capacity lower limit SOCINTL is maintained at the value set in step S102.

  In subsequent step S105, a value obtained by subtracting the discharge depth calculation execution determination discharge amount DODLMT from the discharge depth calculation reference remaining capacity SOCINT is set as the discharge depth calculation execution lower limit threshold SOCLMTL. In subsequent step S106, a value obtained by adding the discharge depth calculation execution determination charge amount SOCUP to the discharge depth calculation reference remaining capacity SOCINT is set as the discharge depth calculation execution upper limit threshold SOCLMTH. In step S107, the discharge depth calculation execution flag F_DODLMT is set to “0” (not executed), and in step S108, the discharge depth DOD is set to the initial value “0”, and the discharge seismic intensity calculation routine ends.

  When the starter switch is turned off or not turned on in step S101, it is determined in step S109 whether the remaining capacity SOC exceeds the discharge depth calculation execution upper limit remaining capacity SOCUPH, and the remaining capacity SOC is determined as the discharge depth. When it is determined that the calculation execution upper limit remaining capacity SOCUPH is exceeded, the process proceeds to step S107 and step S108, and the discharge depth calculation is not executed. When it is determined in step S109 that the remaining capacity SOC is equal to or less than the discharge depth calculation execution upper limit remaining capacity SOCUPH, the process proceeds to step S110.

  In subsequent step S110, it is determined whether or not the remaining capacity SOC is equal to or less than the discharge depth calculation execution lower limit threshold SOCLMTL, and if the remaining capacity SOC is equal to or less than the discharge depth calculation execution lower limit threshold SOCLMTL (see point A in FIG. 6). In S111, the discharge depth calculation execution flag F_DODLMT is set to “1” (execution), and in step S112, a value obtained by subtracting the remaining capacity SOC from the discharge depth calculation reference remaining capacity SOCINT is set in the electric depth DOD, and the discharge depth calculation routine is performed. Exit. When it is determined in step S110 that the remaining capacity SOC exceeds the discharge depth calculation execution lower limit threshold SOCLMTL, the process proceeds to step S113.

  When the discharge depth calculation execution flag F_DODLMT is set to “1” (execution) in step S113, that is, when the discharge depth DOD is being calculated, the remaining capacity SOC is set to the discharge depth calculation execution upper limit in step S114. It is determined whether or not the threshold SOCLMTH is exceeded, and if the remaining capacity SOC exceeds the discharge depth calculation execution upper limit threshold SOCLMTH (see point B in FIG. 6), the process proceeds to step S102 to step S108 to execute the process. Then, the discharge depth calculation routine ends. In step S102, the alga discharge depth calculation reference remaining capacity SOCINT is updated with the remaining capacity SOC transferred from step 114, and the process is executed.

  When the discharge depth calculation execution flag F_DODLMT is set to “0” (not executed) in step S113, the discharge depth calculation routine is executed when it is determined in step S114 that the remaining capacity SOC is equal to or less than the discharge depth calculation execution upper limit remaining capacity SOCUPH. Exit.

  Next, the power generation execution determination routine, which is a subroutine of step S12, will be described based on the flowchart of FIG.

  First, in step S201, it is determined whether or not the remaining capacity SOC of the storage battery 11 is less than the REV mode power generation execution upper limit remaining capacity SOCREV, and when it is determined that the remaining capacity SOC of the storage battery 11 is greater than or equal to the REV mode power generation execution upper limit remaining capacity SOCREV, In step S202, the power generation execution flag F_GEN = “0” is set, power generation by the auxiliary power unit 33 is stopped, and the power generation execution determination routine is ended. Even when the remaining capacity SOC of the storage battery 11 is determined to be less than the REV mode power generation execution upper limit remaining capacity SOCREV in step S201, the cooling water temperature TW of the internal combustion engine 12 detected by the cooling water temperature sensor is determined in the subsequent step S203. When it is determined that the EV mode execution upper limit water temperature TWEV or less, since the warm-up of the internal combustion engine 12 is not completed, the power generation execution flag F_GEN is set to “0” in step S202, and the power generation by the auxiliary power unit 33 is stopped. The power generation execution determination routine is terminated.

  In step S201, it is determined that the remaining capacity SOC of the storage battery 11 is less than the REV mode power generation execution upper limit remaining capacity SOCREV, and the cooling water temperature TW of the internal combustion engine 11 detected by the cooling water temperature sensor in step S203 is the EV mode execution upper limit water temperature TWEV. When it is determined that the value exceeds the value, the power generation execution lower limit vehicle speed VPENDOD according to the discharge depth is searched in the table in step S204 using the discharge depth DOD as a parameter. Note that the power generation execution lower limit vehicle speed VPENDOD according to the depth of discharge decreases as the depth of discharge DOD increases. That is, when the capacity of the storage battery 11 is reduced, the auxiliary power unit 33 is operated at a low vehicle speed, whereby the frequency of EV traveling is reduced and overdischarge of the storage battery 11 is suppressed.

  In subsequent step S205, a table search is performed for a power generation execution lower limit vehicle speed VPGENSOC based on the remaining capacity using the remaining capacity SOC as a parameter. Note that the power generation lower limit vehicle speed VPGENSOC based on the remaining capacity decreases as the remaining capacity SOC decreases. That is, when the capacity of the storage battery 11 is reduced, the auxiliary power unit 33 is operated at a low vehicle speed, whereby the frequency of EV traveling is reduced and overdischarge of the storage battery 11 is suppressed.

  In subsequent step S206, it is determined whether or not the vehicle speed VP exceeds the power generation execution lower limit vehicle speed VPENDOD by the depth of discharge. When the vehicle speed VP is equal to or lower than the power generation execution lower limit vehicle speed VPENDOD by the discharge depth, the vehicle speed VP is generated by the remaining capacity in step S207. It is determined whether or not the lower limit vehicle speed VPGENSOC is exceeded. When the vehicle speed VP is equal to or lower than the power generation execution lower limit vehicle speed VPGENSOC based on the remaining capacity, the power generation execution flag F_GEN = “0” is set in step S202 to stop the power generation by the auxiliary power unit 33, and the power generation execution determination routine ends.

  When it is determined in step S206 that the vehicle speed VP exceeds the power generation execution lower limit vehicle speed VPENDOD according to the depth of discharge, in step S207, when it is determined that the vehicle speed VP exceeds the power generation execution lower limit vehicle speed VPGENSOC due to the remaining capacity, the power generation execution flag F_GEN = "1" is set to start power generation by the auxiliary power unit 33, and the power generation execution determination routine is ended.

  As a result, when the discharge depth DOD of the storage battery 11 increases or when the remaining capacity SOC of the storage battery 11 decreases, that is, when the storage battery 11 may be overdischarged, the auxiliary power unit 33 operates to generate power. By reducing the starting vehicle speed VP, overdischarge of the storage battery 11 can be prevented in advance.

  Next, the power generation amount calculation routine, which is a subroutine of step S14, will be described based on the flowchart of FIG.

  First, in step S401, a table search is performed for a power generation amount PGENRL corresponding to an output necessary for cruising at each vehicle speed using the vehicle speed VP as a parameter. The power generation amount PGENRL corresponding to the output required for cruising at each vehicle speed is the power generation amount that the auxiliary power unit 33 should generate in order for the electric motor 14 to generate a driving force that overcomes the rolling resistance and air resistance of the vehicle. It increases as the vehicle speed VP increases.

  In the next step S402, the vehicle speed VP and the road surface gradient estimated value θ calculated in step S10 are used as parameters to search the map for each vehicle speed and the power generation correction amount PGENLSLP of the gradient.

  In subsequent step S403, a table search is performed for the power generation amount PGENBASE added to power generation at each vehicle speed using the vehicle speed VP as a parameter. The additional power generation amount PGENBASE at each vehicle speed decreases as the vehicle speed VP increases.

  In the subsequent step S404, a map search is made for the power generation additional amount PENDOD for each vehicle speed and discharge depth using the vehicle speed VP and the discharge depth DOD as parameters, and in step S405, the power generation additional amount PGENSOC for each vehicle speed and remaining capacity is used for the vehicle speed VP and remaining capacity SOC as parameters. Search for a map. If the depth of discharge DOD increases or the remaining capacity SOC decreases, the additional power generation amount PGENBASE at each vehicle speed may be insufficient. Therefore, the additional power generation amount PENDOD at each vehicle speed and discharge depth and the additional power generation amount at each vehicle speed and remaining capacity. The power generation additional power generation amount PGENBASE at each vehicle speed is corrected by the amount PGENSOC.

  In the subsequent step S406, a table search is performed for the power generation additional amount PGENAC when using the air conditioning at each vehicle speed using the vehicle speed VP as a parameter.

  In step S407, it is determined whether or not the air conditioning use flag F_AC = “1” (air conditioning used). If the air conditioning use flag F_AC = “0” (no air conditioning is used) and neither the electric compressor 22 nor the electric heater 23 is used, in step S408, the power generation amount PGENRL corresponding to the output required for cruising at each vehicle speed, The generator power generation output PREQGEN is calculated by adding the power generation correction amount PGENLSLP of the gradient, the power generation additional power generation amount PGENBASE at each vehicle speed, the power generation additional amount PENDOD of each vehicle speed and discharge depth, and the power generation additional amount PGENSOC of each vehicle speed and remaining capacity, The power generation amount calculation routine is terminated.

  In step S407, if the air conditioning use flag F_AC = “1” and the electric compressor 22 or the electric heater 23 is used, in step S409, the power generation amount PGENRL corresponding to the output required for cruising at each vehicle speed, each vehicle speed, and The power generation correction amount PGENLSLP of the gradient, the power generation additional power generation amount PGENBASE at each vehicle speed, the power generation additional power amount PENDOD at each vehicle speed and discharge depth, the power generation additional power amount PGENSOC at each vehicle speed and the remaining capacity, and the power generation additional amount PGENAC at the time of air conditioning use at each vehicle speed The generator power generation output PREQGEN is calculated by addition, and the power generation amount calculation routine is terminated.

  In the present embodiment, the power generation amount PGENRL corresponding to the output required for cruising at each vehicle speed, which is an output corresponding to rolling resistance and air resistance that is always generated when the vehicle travels, is set as a predetermined margin amount. The auxiliary power unit 33 generates an output obtained by adding “power generation added power generation amount PGENBASE at each vehicle speed”, and other outputs that are temporarily required for acceleration and the like, and outputs that are required for EV traveling at low vehicle speeds. Is covered by the electric power stored in the storage battery 11. That is, it can be said that the control of the auxiliary power unit 33 according to the present embodiment is “cruising output follow-up power generation”.

This “cruise output follow-up control” provides the best fuel efficiency because the engine speed increases when the required power generation required by the motor is large. The problem that the fuel efficiency is greatly deteriorated when driving with the output of the auxiliary power unit and the vibration and noise increase due to the increase in the number of revolutions of the internal combustion engine when the required power generation amount is large is solved. Is done. In addition, if the internal combustion engine is downsized to reduce fuel consumption and CO ₂ emissions, which is a problem of conventional “fixed-point operation type power generation control”, and the engine is operated at the best point of fuel consumption, the amount of power generated by the generator will reduce the required driving force of the motor. The problem that the battery cannot be satisfied and the storage battery tends to discharge and it becomes difficult to maintain energy is solved.

  In addition, since “the power generation amount PGENRL corresponding to the output necessary for cruising at each vehicle speed” is set according to the vehicle speed VP, the storage battery 11 can be charged with the surplus output of the generator 13 during downhill or deceleration. Therefore, the power generation frequency of the generator 13 is increased during downhill or deceleration without performing high-output power generation that lowers the efficiency of the internal combustion engine 12, thereby making it easier to maintain the energy of the storage battery 11.

  Further, in the present embodiment, “the power generation implementation lower limit vehicle speed VPENDOD by the depth of discharge” and “the power generation implementation by the remaining capacity” which are vehicle speeds switched from EV running to REV running (that is, running by the electric power generated by the auxiliary power unit 33). Since the “lower limit vehicle speed VPGENSOC” is changed in accordance with the remaining capacity SOC of the storage battery 11 and the discharge depth DOD, it is possible to accurately perform energy control at low vehicle speed and low output.

  Further, since the “power generation amount PGENRL corresponding to the output necessary for cruising at each vehicle speed” during REV traveling is corrected by “the power generation correction amount PGENSLP of each vehicle speed and gradient”, the auxiliary power unit is compensated for the influence of the road surface gradient. In addition to appropriately controlling the power generation amount of 33, the “power generation additional power generation amount PGENBASE” at each vehicle speed is changed to “the power generation additional power generation amount PENDOD at each vehicle speed and discharge depth” and “the power generation additional power generation amount PGENSOC of each vehicle speed and remaining capacity”. ”And“ Additional power generation amount PGENAC when using air-conditioning at each vehicle speed ”, the power generation amount of the auxiliary power unit 33 is appropriately controlled by compensating for the effects of remaining capacity SOC, discharge depth DOD, and air-conditioning load. Therefore, it becomes possible to accurately perform energy control at medium and high vehicle speeds and medium and high power outputs.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, a plug-in type hybrid vehicle has been described, but the present invention can also be applied to a series type hybrid vehicle or a parallel type hybrid vehicle capable of running in series.

  The method for calculating the discharge depth DOD is not limited to the embodiment, and any method can be adopted.

DESCRIPTION OF SYMBOLS 11 Storage battery 12 Internal combustion engine 13 Generator 14 Electric motor 22 Electric compressor (air conditioner)
23 Electric heater (air conditioner)
24 Control device DOD Depth of discharge PGENRL Power generation amount PGENBASE corresponding to the output required for cruising at each vehicle speed Additional power generation amount SOC remaining capacity VP Vehicle speed θ Road surface gradient estimated value at each vehicle speed

Claims (13)

A generator driven by an internal combustion engine, a storage battery for storing electric power generated by the generator, and a control device for controlling the internal combustion engine and the generator;
The control device determines whether or not the generator can generate power according to the state of the storage battery, and when generating power, sets a power generation amount corresponding to the output necessary for the cruise according to the running state, and the vehicle A power generation of a hybrid vehicle characterized in that an additional power generation amount is set according to a power amount required depending on a state and a running state, and the internal combustion engine and the generator are controlled based on the power generation amount and the additional power generation amount Control device.   The said control apparatus determines the propriety of electric power generation based on the depth of discharge of the said storage battery, The power generation control apparatus of the hybrid vehicle of Claim 1 characterized by the above-mentioned.   The said control apparatus determines the propriety of electric power generation based on the remaining capacity of the said storage battery, The power generation control apparatus of the hybrid vehicle of Claim 1 or Claim 2 characterized by the above-mentioned.   The said control apparatus sets the said electric power generation amount based on a vehicle speed, The power generation control apparatus of the hybrid vehicle of any one of Claims 1-3 characterized by the above-mentioned.   5. The hybrid according to claim 4, wherein the control device derives rolling resistance and air resistance during traveling based on a vehicle speed, and sets the power generation amount based on the derived rolling resistance and air resistance. Power generation control device for automobiles.   6. The power generation control device for a hybrid vehicle according to claim 1, wherein the control device sets the additional power generation amount based on an estimated value of a road surface gradient. 7.   The said control apparatus sets the said additional power generation amount based on the depth of discharge of the said storage battery, The power generation control apparatus of the hybrid vehicle of any one of Claims 1-6 characterized by the above-mentioned.   The said control apparatus sets the said additional power generation amount based on the remaining capacity of the said storage battery, The power generation control apparatus of the hybrid vehicle of any one of Claims 1-7 characterized by the above-mentioned.   The said control apparatus sets the said additional power generation amount based on a vehicle speed, The power generation control apparatus of the hybrid vehicle of any one of Claims 1-8 characterized by the above-mentioned.   An air conditioner that air-conditions the interior of the vehicle is provided, and the control device determines whether the air conditioner can be operated, and sets the additional power generation amount according to the required temperature when the air conditioner is operating. The power generation control device for a hybrid vehicle according to any one of claims 1 to 9, wherein:   The said control apparatus correct | amends the said additional power generation amount according to a vehicle speed, The power generation control apparatus of the hybrid vehicle of any one of Claims 1-10 characterized by the above-mentioned.   The power generation control device for a hybrid vehicle according to any one of claims 1 to 11, wherein the control device sets a rotational speed of the internal combustion engine from the power generation amount and the additional power generation amount. . A generator driven by an internal combustion engine, a storage battery for storing electric power generated by the generator, an air conditioner that air-conditions a vehicle interior, and a controller that controls the air conditioner, the internal combustion engine, and the generator ,
The controller is
Determining whether or not power generation is possible based on at least one parameter of the discharge depth and remaining capacity of the storage battery,
When power generation is permitted, at least one of air resistance and rolling resistance during driving is derived based on the vehicle speed, and a power generation amount corresponding to the output required for the cruise is set based on the derived resistance.
An additional power generation amount is set based on at least one parameter of a vehicle gradient estimation value, a discharge depth of the storage battery, a remaining capacity of the storage battery, a vehicle speed, and a required temperature of the air conditioner, and the set power generation amount and the A power generation control device for a hybrid vehicle, wherein the number of revolutions of the internal combustion engine is set from the amount of power generation added.

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