JP4512057B2 - Drive control apparatus for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve fuel cost of a hybrid vehicle having an engine and a generator motor as a driving source. <P>SOLUTION: A plurality of transmission gear ratio candidates are calculated based on a vehicle requiring driving force, and a candidate of a specific power generation torque of the generator motor and a candidate of a specific assist torque are calculated relative to each of the plurality of transmission gear ratio candidates, and a plurality of combination candidates on a driving pattern between a plurality of engine output torque candidates and the specific power generation torque candidate and on a driving pattern between the plurality of engine output torque candidates and the specific assist torque are operated, relative to each of the plurality of transmission gear ratio candidates, and a fuel consumption equivalent amount is calculated in each combination candidate of each driving pattern, and a driving pattern wherein the fuel consumption equivalent amount becomes minimum is determined, to thereby always drive the vehicle with the best fuel cost. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a drive device for a hybrid vehicle having an engine and a generator motor as drive sources for the vehicle.

  The hybrid vehicle having an engine and an electric motor as a power source includes a series system in which the engine is driven as a power source for power generation and an electric motor is driven as a power source for traveling, There is a parallel system in which an engine is driven as a power source, and an electric motor is auxiliary driven when starting or accelerating. As a type combining the series method and the parallel method, there is a series / parallel method in which one or both of the electric motor and the engine are driven in accordance with the traveling state.

  In a parallel type or series / parallel type hybrid vehicle, it is possible to switch between series running by an electric motor and parallel running by an electric motor and an engine. In Patent Document 1, an engine torque steady deviation during series running is obtained from a motor current value and an engine torque command value during series running, and the engine torque command value is corrected using the engine torque steady deviation during parallel running. A speed control device for a hybrid vehicle is described.

In order to improve the fuel consumption of the hybrid vehicle, Patent Document 2 calculates the best fuel consumption rotation speed that is the rotation that can be output with the best fuel consumption, and the optimum secured rotation speed that is the lowest rotation speed that can output the maximum output, A control device is described in which the larger one of these two rotational speeds is selected as the target input rotational speed of the transmission, so that the driving range of the engine does not deviate from the best fuel consumption line while ensuring sufficient drive output. ing.
JP 2004-58776 A Japanese Patent Application Laid-Open No. 2002-254962

  For driving a hybrid vehicle having an engine and a generator motor as a driving source, a driving pattern for driving the vehicle by the engine and the generator motor, a driving pattern for driving the vehicle while generating power by driving the generator motor by the engine, and There is a drive pattern in which the generator motor is stopped and travels by the engine. There are various combinations of engine output values and assist output values in driving patterns in which the vehicle is driven by the engine and the generator motor. Similarly, in driving patterns in which the vehicle is driven while generating power by the engine, the engine There are various patterns of combinations of output values and power generation output values.

  Conventionally, a drive pattern in which the engine is operated in a region where the fuel efficiency is high is selected. However, depending on the traveling environment and traveling state of the vehicle, this is insufficient from the viewpoint of improving fuel efficiency. Further, it is necessary to appropriately set the drive pattern depending on the remaining capacity of the battery that supplies power to the generator motor and stores the power generated by the generator motor.

  An object of the present invention is to improve the fuel efficiency of a hybrid vehicle having an engine and a generator motor as drive sources.

  Another object of the present invention is to convert the power generation output into engine fuel consumption when generating the generator motor, and to convert the motor assist output into engine fuel consumption when assisting the engine with the motor torque of the generator motor. In conversion, the engine and the generator motor are driven by a drive pattern that minimizes the total fuel consumption.

  Another object of the present invention is to select a drive pattern according to the remaining capacity of the battery so that the remaining capacity of the battery can be maintained at an optimum value.

A drive control apparatus for a hybrid vehicle according to the present invention includes a transmission disposed between a power unit shaft connected to an engine as a drive source and a generator motor and drive wheels, and the generator motor supplies the drive wheels to the drive wheels. A drive control device for a hybrid vehicle that assists the drive force or generates the generator motor by the drive force of the engine, the vehicle request drive force calculation unit for calculating the vehicle request drive force of the driver, A gear ratio candidate calculation unit that calculates a plurality of gear ratio candidates based on the vehicle required driving force, and one generator torque candidate and one assist torque candidate for the generator motor for each of the plurality of gear ratio candidates. For each of the generator motor torque candidate calculation sections to be calculated and the plurality of speed ratio candidates, A drive pattern combination candidate calculation unit for calculating a drive pattern of a plurality of engine output torque candidates and one power generation torque candidate, and a combination candidate for drive patterns of a plurality of engine output torque candidates and one assist torque candidate, and a power generation torque The fuel consumption equivalent amount at the time of power generation calculated by the sum of the converted fuel consumption amount converted into engine fuel consumption amount and the engine fuel consumption amount for driving the vehicle, and the assist torque converted into engine fuel consumption amount The fuel consumption equivalent amount at the time of assist calculated by the sum of the converted fuel consumption amount and the engine fuel consumption amount for driving the vehicle is obtained for each combination candidate of the drive patterns, and the fuel consumption equivalent amount is calculated. A fuel consumption comparison unit that determines a drive pattern that minimizes the amount, and depending on the determined drive pattern And controlling serial engine and the generator motor.

In the drive control apparatus for a hybrid vehicle of the present invention, calculated on the basis of the first replacement efficiency coefficients of the terms of fuel consumption is preset a generator the power generation efficiency and the generator power output during power generation, said time assist and calculating on the basis of the converted fuel consumption and a second replacement efficiency coefficient set in advance and the motor output efficiency and motor assist output.

  In the drive control apparatus for a hybrid vehicle of the present invention, the first replacement efficiency coefficient and the second replacement efficiency coefficient are the same.

  The drive control apparatus for a hybrid vehicle according to the present invention is characterized in that the replacement efficiency coefficient is variable based on a remaining battery capacity (SOC).

  In the drive control apparatus for a hybrid vehicle of the present invention, a plurality of candidates for power generation torque and a plurality of candidates for assist torque are set in advance for each of the gear ratio candidates.

In the hybrid vehicle drive control device of the present invention, the fuel consumption equivalent amount for the drive pattern combination candidate when assisting is calculated first, and the engine output torque is all applied to the drive wheels from the fuel consumption equivalent amount. If the fuel consumption equivalent amount without transmission assist is smaller, the fuel consumption equivalent amount is obtained for the drive pattern combination candidate when power is generated, and the combination candidate with the smallest value is determined as the drive pattern. It is characterized by doing.

In the hybrid vehicle drive control device of the present invention, when the drive pattern to generate power is determined, the generator motor at the time of power generation is obtained by the ratio between the generated power and the fuel consumption increase amount of the engine for power generation. When the power generation rate is not within the predetermined power generation permission reference value range, the power generation state is not permitted or another drive pattern is determined. The power generation permission reference value is variable depending on a remaining battery capacity (SOC).

In the hybrid vehicle drive control device of the present invention, when the drive pattern to be assisted is determined, the motor output of the generator motor at the time of assist, which is obtained by the ratio between the discharge power and the fuel consumption reduction amount of the engine by the assist. When the rate is not within a predetermined assist permission reference value range, the assist state is not permitted or another drive pattern is determined. The assist permission reference value is variable depending on a remaining battery capacity (SOC).

  The drive control apparatus for a hybrid vehicle according to the present invention includes a torque converter provided with a lock-up clutch, and includes transmission gear ratio information when the lock-up clutch is on and off.

  According to the present invention, a plurality of speed ratio candidates are calculated based on the vehicle required driving force, and a specific power generation torque candidate and a specific assist torque candidate of the generator motor are calculated for each of the plurality of speed ratio candidates. , For each of the plurality of gear ratio candidates, a plurality of combination candidates for a drive pattern of a plurality of engine output torque candidates and a specific power generation torque candidate and a drive pattern of a plurality of engine output torque candidates and a specific assist torque By calculating and calculating the fuel consumption equivalent amount for each drive pattern combination candidate and determining the drive pattern that minimizes the fuel consumption equivalent amount, the vehicle can always be driven with the best fuel consumption. .

In the present invention, the fuel consumption equivalent amount at the time of power generation is calculated by the sum of the converted fuel consumption amount obtained by converting the power generation torque into the engine fuel consumption amount and the engine fuel consumption amount. It is calculated by the sum of the converted fuel consumption converted into the engine fuel consumption and the engine fuel consumption. The converted fuel consumption during power generation is calculated based on the generator power generation efficiency and the generator power generation output and a preset first replacement efficiency coefficient. The converted fuel consumption during assist is calculated based on the motor output efficiency and the motor assist output. It is calculated based on a preset second replacement efficiency coefficient. Furthermore, the replacement efficiency coefficient can be made variable based on the remaining battery capacity (SOC).

  In the present invention, when the fuel consumption equivalent amount is calculated for the drive pattern combination candidate with the first assist, and the fuel consumption equivalent amount without the assist is smaller than the fuel consumption equivalent amount. Can determine the fuel consumption equivalent amount for the drive pattern combination candidate when power is generated and determine the combination candidate having the smallest value as the drive pattern.

  In the present invention, when the drive pattern for power generation is determined, the power generation rate of the generator motor at the time of power generation determined by the ratio of the generated power and the increase in fuel consumption by power generation is within a predetermined power generation permission reference value range. If not, the power generation state is not allowed or another drive pattern can be determined. This power generation permission reference value can be made variable by the remaining battery capacity (SOC).

  In the present invention, when the driving pattern to be assisted is determined, the motor output rate of the generator motor at the time of assist determined by the ratio between the discharge power and the fuel consumption reduction amount by assist is within a predetermined assist permission reference value range. If not, the assist state is not permitted or another drive pattern can be determined. This assist permission reference value can be made variable by the remaining battery capacity (SOC).

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a skeleton diagram showing a drive device mounted on a hybrid vehicle. This drive device 10 has an engine 11 and a generator motor 12 as drive sources. The generator motor 12 has a function of a motor as a vehicle drive source and a function of a generator, that is, a generator. In the following description, the generator motor 12 is described as both the motor 12 and the generator 12.

  The crankshaft 13 of the engine 11 is connected to the power unit shaft 14, and the generator motor 12 includes a rotor 15 attached to the power unit shaft 14 and a stator 17 disposed outside the rotor 15 and fixed to the power unit case 16a. I have. The power unit shaft 14 is connected to the transmission input shaft 19 via the torque converter 18, and the engine torque and the motor torque transmitted to the power unit shaft 14 are transmitted to the transmission input shaft 19. Further, during power generation, the engine torque is transmitted to the rotor 15 via the power unit shaft 14.

  The torque converter 18 includes a pump shell 21 fixed to the power unit shaft 14 and provided with a front cover 20, and a turbine runner 24 attached to the turbine shaft 23 facing the pump impeller 22 provided on the pump shell 21. The turbine shaft 23 is connected to the transmission input shaft 19. The torque converter 18 is provided with a lockup clutch 25. The lockup clutch 25 is engaged with the front cover 20 to release the lockup-on state in which the crankshaft 13 is directly connected to the turbine shaft 23 and the direct connection state between the power unit shaft 14 and the turbine shaft 23 apart from the front cover 20. A lockup-off state in which the power of the drive source is transmitted to the transmission input shaft 19 via the turbine shaft 23 via the torque converter 18, and slip torque is transmitted to the transmission input shaft 19 by slip contact with the front cover 20. Operates in slip condition.

  A transmission 26 having a transmission input shaft 19 is incorporated in a transmission case 16b connected to the power unit case 16a. The transmission 26 has transmission elements such as clutches and brakes in addition to a plurality of planetary gear trains, and the power transmission path from the transmission input shaft 19 to the transmission output shaft 27 is switched by on / off control of the transmission elements. . As a result, the power unit power or torque input to the transmission input shaft 19 is converted to drive torque by the transmission 26 and is transmitted to the transmission output shaft 27 after being shifted. The transmission output shaft 27 is connected to a front wheel (not shown) as a drive wheel via a front wheel output shaft 28 and a front differential mechanism 29. A center differential mechanism 31 is incorporated in an extension case 16c connected to the transmission case 16b, and the transmission output shaft 27 is connected to a rear wheel (not shown) as a drive wheel via a rear wheel output shaft 32. ing. The center differential mechanism 31 is provided with a differential limiting clutch 33. By engaging the differential limiting clutch 33, the differential rotation of the pinion gear 34 is suppressed and the torque distribution ratio of the front and rear wheels is 50:50. Can be fixed to.

  Thus, the drive device 10 includes the engine 11 and the motor 12 as power sources, and can transmit the drive torque of one or both of the engine 11 and the motor 12 to the drive wheels. Further, the generator 12 can be driven by the engine 11 to charge the battery, and the vehicle can be driven by the engine 11 while charging. The drive device 10 is mounted on a parallel-type all-wheel drive hybrid vehicle. If the drive device 10 is not provided with the center differential mechanism 31, the drive device 10 is a drive for a hybrid vehicle having only the front wheels as drive wheels. It becomes a device. For example, the driving device 10 can drive the engine 11 as a main power source when the vehicle is traveling, and can assist the vehicle with assist torque of the motor 12 when starting or accelerating. The generator motor 12 functions as a generator during braking, and can collect regenerative energy and charge the battery.

  FIG. 2 is an output characteristic diagram of the engine 11 and the generator motor 12, and shows the relationship among the rotational speed of the power unit shaft 14, the output torque of the engine 11, the power generation torque and the assist torque of the generator motor 12. In FIG. 2, alternate long and short dash lines ηf1 to ηf4 indicate the fuel consumption rate map of the engine 11, and the fuel consumption rate of the engine 11 decreases as it goes from ηf1 to ηf4. Become. In FIG. 2, alternate long and short dash lines ηm1 to ηm3 indicate a motor output efficiency map when the generator motor 12 is operated as a motor, and the motor output efficiency increases from ηm1 to ηm3. On the other hand, alternate long and short dash lines ηg1 to ηg3 indicate a generator power generation efficiency map when the generator motor 12 is operated as a generator, and the generator output efficiency increases from ηg1 to ηg3. In FIG. 2, thick lines indicate change characteristics of the maximum output torque of the engine, the maximum assist torque of the motor, and the maximum power generation torque of the generator, respectively. In this specification, the fuel consumption rate is g / kwh generated by the engine, and the lower the value, the better the fuel consumption.

  The power of the power unit transmitted from the engine 11 and the motor 12 to the transmission input shaft 19 via the torque converter 18 is shifted by the transmission 26 and transmitted from the transmission output shaft 27 to the drive wheels. Is set to the engine speed and the engine torque indicated by point 1st (first speed) to point 5th (fifth speed) according to the shift speed, The same driving force Hp can be transmitted at the shift speed. That is, in order to satisfy the driver's required horsepower, that is, the vehicle required driving force Hp, when the driver depresses the accelerator pedal, the engine speed and the output torque change as indicated by points 1st to 5th in FIG. It will be. When the accelerator pedal depressing operation is performed and the required vehicle driving force Hp to be transmitted to the driving wheels changes, the required vehicle driving force Hp at each gear stage changes in the vertical axis direction in FIG.

  Each point 1st to 5th indicates a lockup clutch on state in which the lockup clutch 25 is fastened to the front cover 20. When the lock-up clutch 25 is separated from the front cover 20 under the respective shift speeds, the engine speed becomes the lock-up off (L / U: OFF) speed indicated by x, and the lock-up clutch 25 is in the slip state. In this case, the engine speed is an intermediate speed between each point 1st to 5th and the position of the mark x.

  When only the engine power is transmitted to the drive wheels without operating the generator motor 12 as a motor or a generator, only the engine torque is transmitted to the drive wheels. On the other hand, in order to transmit the power Hp necessary for the drive wheels while generating the generator 12 by the engine 11, it is necessary to increase the engine torque as indicated by a thick arrow, and the increased engine torque is generated by the generator 12 as the power generation torque. As transmitted. On the other hand, in order to transmit the power Hp required for the drive wheels from the engine 11 and the motor 12, the engine power is reduced by an amount corresponding to the assist torque from the motor 12. For example, in FIG. 2, the thick arrow indicates an increase in the output torque of the engine 11 for generating power from the generator 12 at the second to fourth gears, and this increase corresponds to the power generation torque of the generator 12. To do. A thin arrow indicates an increase in assist torque by the motor 12, and this increase corresponds to a torque decrease in the engine 11.

  FIG. 3 is a drive pattern diagram showing an example of drive patterns of the engine 11 and the generator motor 12 when the power unit output Pu is output from the drive source to the power unit shaft 14. As shown in FIG. 3, when the assist output of the motor 12 is added to the driving force of the vehicle, a plurality of engine output (Pe1 to Pe3) candidates and a plurality of motor assist output (Pm1 to Pm3) candidates Can be output as a unit output Pu to the power unit shaft 14 based on a drive pattern consisting of a specific engine output and a motor assist output selected from a combination of a plurality of drive patterns.

  Similarly, when the vehicle is driven while the generator 11 is driven by the engine 11 to generate electric power, a plurality of engine output (Pe5 to Pe7) candidates and a plurality of generator power generation output (Pg1 to Pg3) candidates are used. Driving the generator 12 to a specific generator power output while transmitting a specific engine output to the power unit shaft 14 based on a specific drive pattern selected from a combination of a plurality of drive patterns. it can. When the generator motor 12 is stopped, the engine output Pe4 is transmitted to the power unit shaft 14 as the power unit output Pu.

  FIG. 4 is a fuel efficiency characteristic diagram showing the relationship between the output torque of the engine 11 and the fuel consumption under the condition that the engine speed is the same. When the generator 11 is driven by the engine 11 to generate power, the power generation output of the generator 12 can be converted into the fuel consumption of the engine. On the other hand, when assisting vehicle driving by the motor 12, the assist output of the motor 12 can be converted into the fuel consumption of the engine. FIG. 4 shows a fuel consumption characteristic line indicating the relationship between the converted fuel consumption and the engine torque by converting the power generation output at the time of power generation of the generator motor 12 and the assist output at the time of assist into the fuel consumption of the engine. ing.

  In FIG. 4, when the same power generation torque is output from the engine to the generator 12 and the same assist torque is output from the motor 12 in each of the region where the engine output torque is small and the region where the engine output torque is large, A fuel consumption amount converted into consumption amount and a fuel consumption amount obtained by converting assist torque into engine fuel consumption amount are shown. In both power generation and assist, the region where the engine output torque is larger than the region where the engine output torque is small increases the fuel consumption of the converted engine for obtaining the same torque.

  In order to generate power by driving the generator 12 by the engine 11, as shown in FIG. 4, the converted fuel consumption Fg1 when generating power in a region where the engine torque is small generates power in a region where the engine torque is large. Therefore, the amount of fuel consumption of the engine is smaller when power is generated in a region where the engine torque is small. On the other hand, in order to assist the vehicle drive by the motor 12, as shown in FIG. 4, the converted fuel consumption of the motor 12 for obtaining the same assist torque drives the motor 12 in a region where the engine torque is large. In this case, the converted fuel consumption Fm2 is larger than the converted fuel consumption Fm1 when the motor 12 is driven in a region where the engine torque is small. The equivalent fuel consumption corresponding to That is, assisting in a region where the engine torque is large saves the fuel consumption of the engine, and the assist effect is increased.

Therefore, generating power in a region where the engine torque is small increases the power generation effect because the amount of fuel consumed to drive the engine for power generation is reduced. Meanwhile, who assists in the region engine torque is large, the assist effect increases with the terms of the fuel consumption of the engine corresponding to the assist torque increases. Thus, there are cases where it is advantageous for power generation and cases where it is advantageous for assist depending on the output torque of the engine. In addition, as shown in FIG. 2, the fuel consumption rate varies depending on the engine torque and the rotational speed, and the assist efficiency and the power generation efficiency of the generator motor 12 vary depending on the respective torque and rotational speed.

  Therefore, in the present invention, the fuel consumption equivalent amount at the time of power generation is calculated by the sum of the converted fuel consumption amount of the engine converted corresponding to the power generation torque at the time of power generation and the fuel consumption amount of the engine for driving the vehicle. . In addition, at the time of assist, the fuel consumption of the engine for obtaining the engine torque transmitted to the vehicle and the converted fuel consumption of the engine converted to correspond to the motor torque for assisting the engine torque are obtained at the time of assist. Calculate the fuel consumption equivalent amount. Then, with the condition that the fuel consumption equivalent amount is the lowest as one index, as shown in FIG. 3, a plurality of drive patterns composed of combinations of engine output torque candidates and assist output candidates, engine output torque candidates, A specific drive pattern with the lowest amount corresponding to fuel consumption is selected from among a plurality of drive patterns composed of combinations with power generation torque candidates.

  Even when the motor torque and the engine torque are transmitted to the drive wheels in FIG. 3, the engine output of the three drive patterns shown in FIG. When the engine output is Pe3, the fuel consumption may be lower than the case where the engine output is Pe1 and Pe2. Therefore, in the present invention, the fuel consumption equivalent amount obtained by the sum of the fuel consumption of the engine and the converted fuel consumption of the engine converted corresponding to the motor torque is obtained, and the drive pattern in which the drive pattern becomes the lowest To drive the engine 11 and the motor 12. As a result, the gasoline consumption of the entire power unit when the vehicle is driven by the engine 11 and the motor 12 can be reduced.

  Similarly, even when the generator 11 is driven by the engine 11 and the vehicle is driven by the engine 11 while generating electricity, the engine output is expressed as Pe7 among the three driving patterns shown in the figure depending on the traveling state of the vehicle. When the engine output is set to Pe5 and Pe6, the fuel consumption equivalent amount may be lower. Therefore, in the present invention, the fuel consumption equivalent amount obtained by the sum of the fuel consumption of the engine including power generation and the converted fuel consumption of the negative engine converted corresponding to the power generation torque is obtained. The engine 11 and the generator 12 are driven by the lowest driving pattern. Thereby, the gasoline consumption of the whole power unit when driving the vehicle while generating power with the engine 11 can be reduced.

  Thus, by controlling the engine 11 and the generator motor 12 with the power generation amount or the assist amount when the fuel consumption equivalent amount becomes the lowest, the total fuel consumption of the vehicle can be set to the best.

  Therefore, a combination of drive patterns of engine torque candidates and power generation torque candidates when driving power is transmitted to the vehicle while the generator 11 is generating power by the engine 11 based on the driving demand of the vehicle by the driver. A plurality of candidates are calculated, and further, a plurality of drive pattern combination candidates of engine torque candidates and assist torque candidates when engine torque and motor assist torque are transmitted to the drive wheels are calculated. Next, a drive pattern with the smallest amount corresponding to fuel consumption is selected from among all of these drive pattern combination candidates, and it is determined whether to generate power or assist with the selected drive pattern, and the engine 11 and generator motor 12 Control the operation of

  Therefore, for example, when the drive pattern in which the engine output torque is Pe7 and the power generation torque is Pg3 among the seven drive patterns shown in FIG. Thus, the operations of the engine 11 and the generator 12 are controlled. However, when the fuel consumption equivalent amount of the drive pattern having the assist torque candidates (Pm1 to Pm3) is calculated first, and the assist is not performed more than these fuel consumption equivalent amounts (when the engine output torque is Pe4 in FIG. 3) When the fuel consumption equivalent amount of () is smaller, the fuel consumption equivalent amount for the drive pattern having the power generation torque candidate may be obtained to determine the drive pattern having the smallest value. However, in all drive patterns, the engine speed is between the minimum value and the maximum value, and the engine torque is limited to be equal to or less than the maximum value.

To calculate the fuel consumption equivalent amount, the engine fuel consumption converted to the power generation torque when generating electricity, that is, the replacement (converted) fuel consumption, and the engine fuel consumption converted to assist torque when assisting, that is, the replacement (converted) ) Find the fuel consumption.

FIG. 5 is a conceptual diagram showing a conversion method of each replacement fuel consumption, that is, converted fuel consumption at the time of power generation and assist, and the calculation method of each converted fuel consumption will be described below with reference to FIG. .

(During power generation)
First, when the generator 11 is driven by the engine 11 to generate electric power, the relationship between the generator power generation output (Pg) and the engine fuel consumption for obtaining the power generation output, that is, the converted fuel consumption (f) is determined as follows. Street.

The generated power (Eg1) of the generator 12 at this time is
Eg1 = Pg × ηg1 (1).

  However, Pg is a generator power generation output (kW), that is, an output absorbed by the generator motor during power generation, and ηg1 is referred to by a map from the current generator power generation output (Pg) or the current power generation torque and the motor rotation speed. Generator power generation efficiency.

Battery power (V) stored in the battery by power generation is
V = Eg1 × μg1 (2) [2]

  However, μg1 is the current charging efficiency of the battery.

  Considering the power generation of the battery obtained by the above equation [2] as the power generation performed in the past predetermined period, Eg2 = V / μg2 (3).

Here, μg2 represents the average battery charging efficiency in the past predetermined period, and Eg2 represents the generated power in the predetermined period. Further, the engine output (Pe) for driving the generator 12 by the engine 11 and obtaining the generated power (Eg2) during the predetermined period is:
Pe = Eg2 / ηg2 [4]

  Here, ηg2 indicates the generator power generation efficiency in the predetermined period.

The fuel consumption rate (f) required to obtain this engine output (Pe) is
f = Pe · ηf (5)

  However, ηf represents the engine fuel efficiency when power is generated during the predetermined period.

  From the above formulas [1] to [5], the fuel consumption rate (f) of the engine when power is generated by the generator 12 has the following relationship with the generator power generation output (Pg).

f = (ηf · μg1 · ηg1 · Pg) / (ηg2 · μg2) [6]
In this equation [6], when (ηf / ηg2) is λ · R and (μg1 / μg2) is a coefficient K, the equation [6] is expressed as follows.

f = λ · R · K · Pg · ηg1 [7]
In [7], λ is a predetermined coefficient, and R is a replacement efficiency coefficient determined by a ratio of the engine fuel efficiency (ηf) and the generator power generation efficiency (ηg2). Therefore, the converted fuel consumption (f) required for driving the generator 12 by the engine 11, that is, the fuel consumption rate of the engine is proportional to the product of the generator power generation output (Pg), the generator power generation efficiency (ηg1), and λ · R. . Furthermore, in the case of power generation, the converted fuel consumption is a negative value.

(When assisting)
Next, when the engine power is assisted by the motor 12, the relationship between the motor assist output (Pm) and the engine fuel consumption for obtaining the output, that is, the converted fuel consumption (f) is obtained as follows. is there.

Motor power consumption (Em) (kW) during assist is
Em = Pm / ηm (11)

  However, ηm is the motor output efficiency, and is referred to by a map from the current motor assist output (Pm) or the current assist torque and the motor rotation speed.

The battery power (V) of the battery that supplies power to the motor 12 is
V = Em / μm (12)

  However, μm is the current discharge efficiency.

  Here, it is assumed that the battery power V used for the assist obtained in [12] has been generated in the past predetermined period.

When this battery power (V) is converted into generated power (Eg), the generated power (Eg) is
Eg = V / μg (13)

The engine output (Pe) corresponding to this generated power is
Pe = Eg / ηg (14)

However, ηg is the generator power generation efficiency in the predetermined period. The fuel consumption rate (f) required to obtain this engine output (Pe) is
f = Pe × ηf [15]
However, ηf represents the engine fuel consumption rate during power generation in the past predetermined period.

  From the above formulas [11] to [15], the fuel consumption rate (f) of the engine when the motor 12 assists the engine power has the following relationship with the motor assist output (Pm).

f = (Pm · ηf) / (μg · ηm · μm · ηg) [16]
If (ηf / ηg) is λ · R in the equation [16], (1 / (μg · μm)) is a coefficient K, and the equation [16] is expressed as follows.

f = λ · R · Pm · K / ηm [17]
In [17], λ is a predetermined coefficient, and R is a replacement efficiency coefficient obtained by the ratio of the engine fuel efficiency (ηf) and the generator power generation efficiency (ηg) in the past predetermined period as described above. Therefore, the converted fuel consumption (f) corresponding to the assist power of the motor when assisting the engine power by the motor 12, that is, the fuel consumption rate of the engine is proportional to the product of the motor assist output (Pm) and λ · R, Inversely proportional to motor output efficiency (ηm).

As described above, the generator power generation output (Pg) can be converted into the fuel consumption by the replacement efficiency coefficient (R) to calculate the converted fuel consumption, and the motor assist output (Pm) can be calculated as the replacement efficiency coefficient (R). The converted fuel consumption can be calculated by converting into the fuel consumption. The fuel consumption equivalent amount described above is calculated from the sum of each converted fuel consumption amount and the fuel consumption amount for driving the engine. Here, the calculation of the fuel consumption for driving the engine is obtained from the current engine output torque and the rotational speed.

  In this way, the current power generation torque is considered to have been generated in the past predetermined period and the fuel consumption rate at that time is obtained, and the current assist torque is considered to have been generated in the past predetermined period. Find the fuel consumption rate when.

FIG. 6 is a characteristic diagram showing the replacement efficiency characteristic showing the relationship between λ · R and the remaining battery capacity SOC (State of Charge) during power generation and during assist. Here, it can be considered that λ · R in the past predetermined period changes depending on the SOC. In other words, when the SOC is high, there is little need for power generation, so it is considered that power was generated where the engine fuel efficiency and generator power generation efficiency were relatively good. When the SOC was low, it was necessary to generate power regardless of the operating range. It is thought that power was generated where the fuel efficiency and generator power generation efficiency were relatively poor. FIG. 6 shows this relationship. As shown in FIG. 6, as the SOC becomes higher than a reference value (for example, 65%), the replacement efficiency coefficient at the time of assist decreases, and the converted fuel consumption by the assist torque of the motor and the power generation torque of the generator decreases. On the other hand, as the SOC becomes lower than the reference value, the replacement efficiency coefficient during power generation increases, and the converted fuel consumption due to the power generation torque of the generator and the assist torque of the motor increases.

  FIG. 7 is a fuel consumption characteristic diagram showing an example of the fuel consumption equivalent amount during power generation and during assist. In FIG. 7, the power generation outputs Pga to Pgc with the symbols a to c indicate the power generation output values determined as candidates, and the assist outputs PmA to PmC with the symbols A to C indicate the assist output values determined as candidates. .

The fuel consumption equivalent amount corresponding to the power generation outputs Pga to Pgc is calculated by calculating the fuel consumption amount of the engine corresponding to each power generation output (Pg), that is, the converted fuel consumption amount (f) from the above equation [7]. And the sum of the fuel consumption of the engine and the converted fuel consumption for driving the generator. On the other hand, the fuel consumption equivalent amount corresponding to the assist outputs PmA to PmC is obtained by calculating the fuel consumption rate of the engine corresponding to each assist output (Pm), that is, the converted fuel consumption amount (f) from the above equation [17]. It is obtained by the sum of the fuel consumption of the engine for driving the vehicle and the converted fuel consumption.

  Since the replacement efficiency coefficient R having the characteristics shown in FIG. 6 varies depending on the SOC, the fuel consumption equivalent amounts vary depending on the SOC amount as shown in FIG. For example, when the SOC amount is small, the fuel consumption equivalent amount is the smallest at the power generation output Pgc, and when the SOC amount is large, the fuel consumption equivalent amount is the smallest at the power generation output Pga. In the case where the amount is an intermediate value, the fuel consumption equivalent amount is the smallest at the power generation output Pgb. Similarly, for the assist outputs PmA to mC, a value that minimizes the fuel consumption equivalent amount is obtained for each SOC. In this way, the fuel consumption equivalent amount for the plurality of assist outputs and the power generation output is obtained, and the drive pattern of the engine output and the motor generator output is selected based on the value that minimizes the fuel consumption equivalent amount.

  FIG. 7 shows fuel consumption equivalent amounts for three types of SOCs, large, medium, and small. The amount of fuel consumption is classified for each power generation output candidate for each SOC amount by finely classifying the SOC amounts. And the fuel consumption equivalent amount is calculated for each of the assist output candidates. Similarly, as shown in FIG. 7, the power generation output candidates and the assist output candidates are not limited to three, and a large number of candidates are determined for the power generation output and the assist output, and fuel consumption is determined for each candidate. A considerable amount will be calculated.

  Thus, when the amount of SOC, which is the second index value, is added to the fuel consumption equivalent, which is the first index value, the fuel consumption equivalent is shown in FIG. If the drive of the power unit is controlled so as to minimize the fuel consumption equivalent amount shown in FIG. 7 according to the vehicle running situation that changes from moment to moment, the total fuel consumption of the vehicle is maintained while maintaining the SOC of the high voltage battery at an appropriate value. Can be the best.

  In addition to control using fuel consumption equivalent amount as an indicator, at the time of assist, which is determined by the ratio of the generator power generation rate during power generation determined by the ratio between the generated power and the increase in fuel consumption, and the ratio between motor power consumption and the decrease in fuel consumption Using the assist rate as an index, the drive pattern of the engine output and the motor generator output determined by the fuel consumption equivalent amount is evaluated, and the drive pattern can be changed to an efficient drive pattern as follows. Thereby, fuel consumption efficiency can be raised more.

  FIG. 8 is a power generation rate characteristic diagram showing the relationship between the power generation rate and the power generation output. The generator power generation rate ρg during power generation is ρg = Eg / ΔF. Here, Eg represents generated power, and ΔF represents an increase in fuel consumption of the engine due to power generation. The generator power generation rate ρg varies depending on the rotational speed of the power unit, the engine output torque, and the power generation output, that is, the power generation amount. In FIG. 8, ◯ indicates the power generation rate ρg when the rotational speed of the power unit shaft is 2400 rpm and the engine output torque is 60 Nm, and X indicates the rotational speed of the power unit shaft 14 is 2000 rpm and the engine output torque is 30 Nm. The power generation rate ρg is shown for each of the cases where the power generation output is Pga, Pgb, Pbc. In FIG. 8, symbol GP indicates a power generation permission reference value, and the power generation permission reference value GP varies between GPmax and GPmin in accordance with the amount of SOC. When the power generation rate ρg is higher than the power generation permission reference value GP, power is generated by the generator motor 12. On the other hand, when the power generation rate ρg is lower than the power generation permission reference value GP, the driving pattern for stopping power generation is selected, or the driving pattern that is the second or later driving pattern is selected from the side with the smaller fuel consumption equivalent amount. Is done.

  FIG. 9 is an assist rate characteristic diagram showing the relationship between the assist rate ρm and the assist output. The assist rate ρm at the time of assist is ρm = Em / −ΔF. Here, Em represents discharge power, and -ΔF represents the amount of fuel consumption reduction of the engine due to assist. The assist rate ρm also varies depending on the rotational speed of the power unit, the output torque of the engine, and the assist output. In FIG. 9, ◯ indicates the assist rate ρm when the rotational speed of the power unit shaft 14 is 2400 rpm and the engine output torque is 60 Nm, and X indicates that the rotational speed of the power unit shaft 14 is 2000 rpm and the engine output torque is 30 Nm. The assist rate ρm is shown for each case, and the assist outputs are PmA, PmB, and PmC, respectively. In FIG. 9, symbol MP indicates an assist permission reference value, and the assist permission reference value MP varies between MPmax and MPmin in accordance with the amount of SOC. When the assist rate ρm is lower than the assist permission reference value MP, the generator motor 12 assists. On the other hand, when the assist rate ρm is higher than the assist permission reference value MP, the drive pattern for stopping the assist is selected, or the drive pattern that is the second or later is selected from the one with the smaller fuel consumption equivalent amount. Is done.

  As described above, the engine output and the motor generator output drive pattern determined by the fuel consumption equivalent amount are evaluated using the power generation rate and the assist rate as an index, thereby reducing the fuel consumption amount and reducing the engine consumption by the efficient drive pattern. 11 and the generator motor 12 can be controlled. When determining the drive pattern of engine output and motor generator output using the fuel consumption equivalent amount as an index, only the drive patterns that satisfy the power generation permission reference value and the assist permission reference value using the power generation rate and the assist rate as an index are candidates. You may do it.

  FIG. 10 is a block diagram showing a control circuit 40 in the drive control apparatus for a hybrid vehicle of the present invention. The control circuit 40 includes a microprocessor CPU that calculates control signals, a ROM that stores arithmetic expressions and map data, a RAM that temporarily stores data, and the like. The circuit 40 includes the following calculation units and the like.

  The control circuit 40 includes a vehicle required driving force calculation unit 41, which is input with driving state signals such as an accelerator depression amount detection signal, a brake depression detection signal, and a vehicle speed detection signal. The Based on these signals, the calculation unit 41 calculates the required vehicle driving force to be transmitted to the drive wheels, and the calculation result is input to the power unit required torque calculation unit 42. The power unit required torque calculation unit 42 is further input with a signal from a transmission control unit (TCU) 43 and a vehicle speed signal. A transmission control unit (TCU) 43 determines a gear ratio, that is, a gear ratio based on a travel state signal such as an accelerator depression amount, and the determination signal is sent to the power unit required torque calculation unit 42 and the transmission shift of the transmission is also determined. An efficiency signal and a torque ratio detection signal in torque converter 18 are sent. The power unit required torque calculation unit 42 calculates the power unit torque to be output to the power unit shaft 14 and the power unit rotation speed based on the gear ratio, the torque ratio of the torque converter 18, and the like, and the respective calculation results are combined with the drive pattern. The data is sent to the candidate calculation unit 44.

  The power unit required torque calculator 42 sends a power unit rotation speed signal to the generator motor torque candidate calculator 45. The generator motor torque candidate calculation unit 45 is supplied with an SOC amount signal from the high-voltage battery control unit 46, and the generator motor torque candidate is calculated based on the SOC amount and the power unit rotational speed. The unit 45 calculates a plurality of power generation torque candidates and assist torque candidates, and sends a signal to the drive pattern combination candidate calculation unit 44.

  A drive pattern combination candidate signal from the drive pattern combination candidate calculation unit 44 is sent to the fuel consumption comparison unit 47, and an SOC amount signal from the high voltage battery control unit 46 is sent to the fuel consumption comparison unit 47. The drive pattern with the smallest fuel consumption equivalent amount is selected from among the drive pattern combination candidates. Based on the selected drive pattern, an engine request torque signal is sent to the engine control unit (ECU) 48, and a power generation torque signal is sent to the inverter control unit 49 when the generator motor 12 generates power. When assisting, an assist torque signal is sent.

  FIG. 11 is a block diagram showing a modified example of the control circuit 40. In FIG. 11, parts having the same functions as those in the functional configuration shown in FIG. The control circuit 40 shown in FIG. 11 has a gear ratio candidate calculation unit 51. The transmission ratio candidate calculation unit 51 is input with a driving state signal such as an accelerator pedal depression amount detection signal, a brake pedal depression detection signal, and a vehicle speed detection signal. A plurality of gear speed candidates that satisfy the vehicle required torque requested by the driver based on the driving situation, and a plurality of candidates for the operation pattern of the torque converter 18, that is, whether the lockup is turned on, off, or slipped Is sent to the power unit required torque calculator 42. The gear ratio signal determined by the fuel consumption comparison unit 47 is fed back to the transmission control unit (TCU) 43.

  The control circuit 40 shown in FIG. 11 includes a gear ratio candidate calculation unit 51. However, if the function is performed by the transmission control unit (TCU) 43, the control circuit 40 shown in FIG. Also, the same function as that of the gear ratio candidate calculation unit 51 can be achieved.

(Control method 1)
12 is a flowchart showing an algorithm of the first control method by the drive control apparatus of the present invention, and FIG. 13 is a block diagram showing a signal generation state in the control circuit shown in FIG. 10 according to the first control method. FIG. 14 is a characteristic diagram showing a drive pattern in the first control method.

  As shown in FIG. 12, the vehicle required driving force is calculated on the basis of the traveling state of the vehicle such as the depression amount of the accelerator pedal in step S1, and the information of the gear ratio calculated by the transmission control unit 43 is read in step S2. . When the gear ratio is obtained, the power unit required torque calculation unit 42 calculates the power unit torque and the rotational speed corresponding to the gear ratio in step S3. In FIG. 14, for example, the third speed is set based on the information of the gear ratio, and it is indicated that the torque and the rotational speed to be output to the power unit shaft 14 are values indicated by the symbol Hp3.

  Next, in step S4, a plurality of torque candidates for the generator motor 12 are calculated. The torque candidates include power generation torque and assist torque. In FIG. 14, for example, three types of power generation torques Pg1, Pg2, and Pg3 and three types of candidate assist torques Pm1, Pm2, and Pm3 are included. It is calculated. Next, in step S5, a plurality of drive pattern combination candidates are calculated. This combination of drive patterns is shown in FIG. 3, for example. However, this drive pattern includes a case where the regenerative energy is recovered by the generator motor 12 during braking of the vehicle.

  In FIG. 14, it is shown that three types of candidates for the power generation torque and the candidate for the assist torque are provided as candidates. However, the number of candidates can be set arbitrarily, and a plurality of candidates can be obtained in advance. Are stored as map data in the memory corresponding to each gear position.

  In step S6, the fuel consumption equivalent amount is calculated for each of the plurality of drive pattern combination candidates and compared with each other. In step S7, the drive pattern having the smallest fuel consumption equivalent amount among the plurality of drive pattern combination candidates. To decide. The engine torque, that is, the engine output Pe is determined in step S8 according to the determined drive pattern, and the assist torque, that is, the assist output Pm, or the power generation torque, that is, the power generation output Pg, is determined in step S9. Thus, when the drive pattern is determined in step S7, it is determined whether to generate power or to assist. Therefore, in the case of generating power, the generated output is determined in step S9, and in the case of assist, the assist assist output is determined. It is determined.

  With respect to the determined power generation torque and assist torque, the torque efficiency evaluation step of Step 10 is executed, and it is appropriate to drive the generator 12 with the determined power generation output, and the motor is determined based on the determined assist output. Whether or not it is appropriate to drive 12 is evaluated using the power generation rate (ρg) and the assist rate (ρm) described above as indices.

  FIG. 15 is a flowchart showing a subroutine of the torque efficiency evaluation step shown in step S9. In step S11, it is determined whether it is power generation or assist that is determined to have the smallest amount corresponding to fuel consumption. If it is determined that power generation is performed, the power generation rate ρg shown in FIG. 8 is calculated in step S12. If it is determined to be assist, an assist rate ρm shown in FIG. 9 is calculated in step S13. In step S14, it is determined whether or not the power generation rate ρg when the power generation torque determined in step S8 of FIG. 12 is output exceeds the power generation permission reference value Gp. In step S15, the assist torque determined in the same manner is determined. It is determined whether or not the assist rate ρm when outputting is equal to or less than the assist permission reference value Mp.

  If the power generation rate ρg is equal to or greater than the power generation permission reference value Gp when generating power, the power generation torque signal determined in step S9 shown in FIG. 12 is sent to the inverter control unit 49 (step S16). On the other hand, if the assist rate ρm is equal to or less than the assist permission reference value Mp when assisting, the assist torque signal determined in step S9 is sent to the inverter control unit 49 (step S17). If none of the permitted reference values is satisfied, another drive pattern close to the drive pattern determined in step S6 is determined in step S18. Similarly, the engine torque and assist for the new drive pattern are determined. Torque and power generation torque are determined. However, if neither of them satisfies the permission reference value, it may be determined not to generate or assist in step S18.

(Control method 2)
16 is a flowchart showing an algorithm of the second control method by the drive control apparatus of the present invention, and FIG. 17 is a block diagram showing a signal generation state in the control circuit shown in FIG. 11 according to the second control method. FIG. 18 is a characteristic diagram showing a drive pattern in the second control method.

  A driving condition signal such as an accelerator pedal is input to the gear ratio candidate calculation unit 51 of the control circuit 40 shown in FIG. 11, and a plurality of gear ratio candidates that satisfy the vehicle required driving force calculated in step S21 are calculated in step S22. FIG. 17 shows a state in which calculated values of a plurality of speed ratio candidates from candidates 1 to n are input to the power unit required torque calculator 42. In step S23, a plurality (1 to n) of rotational speed candidates and torque candidates of the power unit shaft 14 are calculated for each of the gear ratio candidates, and the torque candidate of the generator motor 12 corresponding to the rotational speed of the power unit shaft 14, that is, the generated torque. Assist torque candidates 1 to n are calculated (step S24). Next, in step S25, drive pattern combination candidates 1 to n, which are combinations of torque candidates 1 to n of the respective generator motors and engine torque candidates, are calculated.

  In FIG. 18, second speed, third speed, and fourth speed are calculated as speed ratio candidates, and drive pattern combination candidates that are combinations of engine torque and power generation torque or assist torque are calculated for each speed ratio candidate. It shows the state that was done. In the case of illustration at each gear stage, the power generation torque and the assist torque are stored in advance in the memory one by one. For each drive pattern combination candidate, a fuel consumption equivalent amount is calculated and compared, and a gear ratio at which the fuel consumption equivalent amount is minimized is determined in step S27. Based on the determined gear ratio, engine torque, Torque or assist torque is determined. The determined gear ratio is sent as a feedback signal to the transmission control unit 43 to set the gear ratio of the transmission 26. For the determined power generation torque or assist torque, the efficiency evaluation step shown in FIG. 15 is executed in step S30 as in step S9 described above.

(Control method 3)
19 is a flowchart showing an algorithm of a third control method by the drive control apparatus of the present invention, and FIG. 20 is a block diagram showing a signal generation state in the control circuit shown in FIG. 11 according to the third control method. FIG. 21 is a characteristic diagram showing a drive pattern in the third control method.

  In this control method as well, as in the second control method, the vehicle condition request calculated in step S31 is input to the speed ratio candidate calculation unit 51 of the control circuit 40 shown in FIG. In step S32, a plurality of gear ratio candidates that satisfy the driving force are calculated. FIG. 20 shows a state where calculated values of a plurality of speed ratio candidates from candidate 1 to candidate n are input to the power unit required torque calculation unit 42. In step S33, a plurality (1 to n) of rotation speed candidates of the power unit shaft 14 are calculated for each of the gear ratio candidates, and a plurality of torque candidates of the generator motor 12, that is, a plurality of power generations, are associated with the rotation speed of the power unit shaft 14. Torque and assist torque candidates 1 to n are calculated (step S34). Next, drive pattern combination candidates 1 to n including combinations of torque candidates 1 to n of the respective generator motors 12 and engine torque candidates are calculated in step S35.

  In FIG. 21, second speed, third speed, and fourth speed are calculated as speed ratio candidates, and for each speed ratio candidate, drive pattern combination candidates that are combinations of engine torque, a plurality of power generation torques, and assist torque. Indicates the calculated state. In the case of the third speed in FIG. 21, for example, three types of power generation torques Pg1, Pg2, and Pg3 and three types of candidate assist torques Pm1, Pm2, and Pm3 are calculated. Similarly, for the second speed and the fourth speed, three types of power generation torque and assist torque are calculated.

  For each drive pattern combination candidate, a fuel consumption equivalent amount is calculated and compared, and a gear ratio that minimizes the fuel consumption equivalent amount is determined in step S37, and engine torque and power generation are determined based on the determined gear ratio. Torque or assist torque is determined. The determined gear ratio is sent as a feedback signal to the transmission control unit 43 to set the gear ratio of the transmission 26. For the determined power generation torque or assist torque, an efficiency evaluation step is executed in step S39 as in step S29 described above.

  In the second control method, as shown in FIG. 18, one specific power generation torque candidate and one assist torque candidate are preset for each shift stage, whereas in the third control method, As shown in FIG. 21, a plurality of power generation torque candidates and a plurality of assist torque candidates are preset for each shift stage.

  In each of the control methods described above, an equivalent fuel consumption amount is calculated for a power generation torque candidate at the time of power generation to calculate a fuel consumption equivalent amount, and a converted fuel consumption amount is calculated for an assist torque candidate at the time of assist to correspond to fuel consumption. The amount is calculated, and the power generation torque or the assist torque with the smallest amount corresponding to fuel consumption among all candidates is determined. However, the fuel consumption equivalent amount for the assist torque candidate is obtained first, and the fuel consumption equivalent amount in the case where the assist is not performed, that is, the generator motor 12 is stopped from the fuel consumption equivalent amount, which is indicated by the engine output Pe4 in FIG. When it is determined that the amount of fuel consumption in the case of engine output is smaller, the amount of fuel consumption corresponding to the power generation torque candidate may be obtained and the power generation torque candidate having the smallest value may be determined. On the other hand, when the fuel consumption equivalent amount for the power generation torque candidate is obtained first, and it is determined that the fuel consumption equivalent amount without power generation is smaller than the fuel consumption equivalent amount, the fuel consumption for the assist torque candidate is determined. An equivalent amount may be obtained and an assist torque candidate having the smallest value may be determined.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, the transmission 26 has first to fifth shift speeds, but the shift speed is not limited to the fifth forward speed. The transmission 26 is not limited to a stepped transmission, and a continuously variable transmission can also be used.

It is a skeleton figure which shows the drive device mounted in a hybrid vehicle. It is an output characteristic diagram of an engine and a generator motor. It is a drive pattern diagram which shows the drive pattern of an engine and a generator. It is a fuel-consumption characteristic diagram which shows the relationship between an engine output torque and fuel consumption. It is a conceptual diagram which shows the conversion system of each substitution fuel consumption amount at the time of electric power generation and assist. It is a characteristic diagram which shows the substitution efficiency characteristic at the time of electric power generation and assist. It is a fuel consumption characteristic diagram which shows an example of the fuel consumption equivalent about each at the time of electric power generation and assist. It is a power generation efficiency characteristic diagram which shows the relationship between a power generation rate and a power generation output. It is an assist rate characteristic diagram which shows the relationship between an assist rate and an assist output. It is a block diagram which shows a control circuit. It is a block diagram which shows the modification of a control circuit. It is a flowchart which shows the algorithm of the 1st control system by a drive control apparatus. It is a block diagram which shows the generation state of the signal in the control circuit of a 1st control system. It is a characteristic diagram which shows the drive pattern in a 1st control system. It is a flowchart which shows the subroutine of the efficiency evaluation step of a torque. It is a flowchart which shows the algorithm of the 2nd control system by a drive control apparatus. It is a block diagram which shows the generation state of the signal in the control circuit of a 2nd control system. It is a characteristic diagram which shows the drive pattern in a 2nd control system. It is a flowchart which shows the algorithm of the 3rd control system by a drive control apparatus. It is a block diagram which shows the generation state of the signal in the control circuit of a 3rd control system. It is a characteristic diagram which shows the drive pattern in a 3rd control system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Drive apparatus 11 Engine 12 Generator motor 13 Crankshaft 14 Power unit shaft 15 Rotor 17 Stator 18 Torque converter 19 Transmission input shaft

Claims (11)

An engine as a drive source and a transmission disposed between a drive unit wheel and a power unit shaft connected to the generator motor, assisting the driving force to the drive wheel by the generator motor, and driving the engine A drive control device for a hybrid vehicle configured to generate the generator motor by force,
A vehicle required driving force calculation unit for calculating a vehicle required driving force of the driver;
A gear ratio candidate calculation unit that calculates a plurality of gear ratio candidates based on the vehicle required driving force;
For each of the plurality of gear ratio candidates, a generator motor torque candidate calculation unit that calculates one generator torque candidate and one assist torque candidate for the generator motor;
For each of the plurality of gear ratio candidates, a combination candidate for a drive pattern of a plurality of engine output torque candidates and one power generation torque candidate and a drive pattern of a plurality of engine output torque candidates and one assist torque candidate is calculated. A drive pattern combination candidate calculation unit to perform,
Equivalent fuel consumption during power generation calculated from the sum of converted fuel consumption converted from engine power consumption to engine fuel consumption and engine fuel consumption for driving the vehicle, and assist torque converted into engine fuel consumption The fuel consumption equivalent amount at the time of assist calculated by the sum of the converted fuel consumption amount and the engine fuel consumption amount for driving the vehicle is obtained for each combination candidate of the drive patterns, and the fuel consumption equivalent amount is calculated. A fuel consumption comparison unit that determines a drive pattern that minimizes the amount,
A drive control apparatus for a hybrid vehicle, wherein the engine and the generator motor are controlled according to the determined drive pattern.
In the drive control apparatus for a hybrid vehicle according to claim 1, calculated on the basis of the converted fuel consumption at the time of power generation in the first replacement efficiency coefficient set in advance a generator the power generation efficiency and the generator power output, the time assist drive control device for a hybrid vehicle and calculates on the basis of the converted fuel consumption and a second replacement efficiency coefficient set in advance and the motor output efficiency and motor assist output. 3. The drive control apparatus for a hybrid vehicle according to claim 2 , wherein the first replacement efficiency coefficient and the second replacement efficiency coefficient are the same. 4. The drive control apparatus for a hybrid vehicle according to claim 3 , wherein the replacement efficiency coefficient is variable based on a remaining battery capacity (SOC). Wherein the drive control apparatus for a hybrid vehicle according to any one of claims 1-4, a plurality of candidates of a plurality of candidates and the assist torque of the generator torque, to set in advance for each of the gear ratio candidate A drive control apparatus for a hybrid vehicle. In the drive control apparatus for a hybrid vehicle according to any one of claims 1 to 5 to calculate the fuel consumption amount corresponding for the combination candidate drive pattern in the case of assisted earlier, than its fuel consumption amount corresponding If the fuel consumption equivalent amount without assist, which transmits all the engine output torque to the drive wheels, is smaller, obtain the fuel consumption equivalent amount for the drive pattern combination candidate when power is generated. A hybrid vehicle drive control apparatus, wherein a combination candidate that decreases is determined as a drive pattern. The drive control device for a hybrid vehicle according to any one of claims 1 to 6 , wherein when a drive pattern to generate power is determined, a ratio between the generated power and the fuel consumption increase amount of the engine for power generation. Drive control of a hybrid vehicle, wherein the power generation state is not permitted or another drive pattern is determined when the power generation rate of the generator motor at the time of power generation determined by the step is not within a predetermined power generation permission reference value range apparatus. 8. The drive control apparatus for a hybrid vehicle according to claim 7 , wherein the power generation permission reference value is variable depending on a remaining battery capacity (SOC). The drive control apparatus for a hybrid vehicle according to any one of claims 1 to 6 , wherein when a drive pattern to be assisted is determined, the ratio is determined by a ratio between a discharge power and a reduction in fuel consumption of the engine due to the assist. The hybrid vehicle drive control device is characterized in that the assist state is not permitted or another drive pattern is determined when the motor output rate of the generator motor at the time of assist is not within a predetermined assist permission reference value range. . In the drive control apparatus for a hybrid vehicle according to claim 9, the drive control apparatus for a hybrid vehicle, characterized in that a variable the assist permission reference value by a battery remaining capacity (SOC). The drive control apparatus for a hybrid vehicle according to any one of claims 1 to 10 , further comprising a torque converter provided with a lock-up clutch, wherein the lock-up clutch is turned on and off as gear ratio information. A drive control apparatus for a hybrid vehicle, comprising:

Images