JP2015116991A - Control device of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress deterioration in fuel economy at the time of heating by appropriately setting an output distribution between an engine and a MG (a motor generator) and an output distribution between a hot water heater and an electric heater.SOLUTION: After EG output (output of an engine 11) and MG output (output of a MG 12) are set based on travel request power, HP output corresponding to the MG output is set on an optimum HP output distribution line connecting the HP output (output of an electric heater 42) maximizing system utility function to the MG output; and HC output (output of a hot-water heater 22) is set by subtracting the HP output from heating request power. This allows the HC output and the HP output to be set so as to maximize the system utility function for the EG output and the MG output, where the system utility function is defined using the travel request power, the heating request power, generated power, discharged power, cooling-water heating power, cooling-water radiating power and fuel consumption power.

Description

  The present invention relates to a control device for a hybrid vehicle equipped with an engine and a motor as a power source for the vehicle.

  In recent years, a hybrid vehicle equipped with an engine and a motor as a power source of the vehicle has attracted attention because of the social demand for low fuel consumption and low exhaust emissions. Such hybrid vehicles tend to deteriorate fuel consumption due to lack of heat in winter. In particular, when the heat of the engine coolant becomes insufficient, the engine is forcibly operated and engine efficiency may be reduced.

  Therefore, as a technique for compensating for the lack of heat of the cooling water, for example, as described in Patent Document 1 (Japanese Patent Laid-Open No. 5-221233), in addition to a hot water heating apparatus that uses the heat of the cooling water of the engine, There is an electric heater equipped with an electric heating device that generates heat. In such a system, when the cooling water temperature is lower than a predetermined value, heating is performed by both the hot water heating device and the electric heating device with the output distribution of the hot water heating device and the electric heating device being constant, and the cooling water temperature is a predetermined value. In some cases, heating is performed only by the hot water heater.

Japanese Patent Laid-Open No. 5-221233

  However, in the prior art, when the cooling water temperature is lower than a predetermined value, the output distribution between the hot water heating device and the electric heating device is made constant.

  Even when the cooling water temperature is low, the heat of the cooling water is taken away by the heater core of the hot water heating apparatus, so that the cooling water temperature may further decrease, and the engine is forcibly operated when the cooling water temperature falls below a predetermined water temperature. While the engine is forcibly operated, EV traveling that stops the combustion of the engine and runs with the power of the motor cannot be performed, so that the fuel consumption deteriorates. Even when the driving load is high and the engine output is large (the amount of heat generated is large), if the cooling water temperature is lower than a predetermined value, electric power is consumed by the electric heating device, and accordingly, the EV traveling distance can be increased accordingly. It becomes shorter and fuel consumption worsens.

  Therefore, the problem to be solved by the present invention is a hybrid vehicle capable of improving fuel efficiency by appropriately setting the output of a power source (engine or motor) or a heating device (hot water heating device or electric heating device) of the vehicle. It is to provide a control device.

  In order to solve the above problems, an invention according to claim 1 is directed to an engine (11) and a motor (12) mounted as a power source of a vehicle, and a generator (12, 17) driven by the engine (11). And a chargeable / dischargeable battery (18, 21), a hot water heater (22) that uses the heat of the cooling water of the engine (11), and an electric heater (42) that generates heat by electricity. In the hybrid vehicle control device, the output of the hot water heating device (22) or the electric heating device (42) in which the system efficiency falls within a predetermined appropriate range with respect to the output of the engine (11) or the motor (12). On the distribution line, it is configured to include a control means (33) for setting the output of the hot water heater (22) or the electric heater (42) corresponding to the output of the engine (11) or the motor (12). That.

  In this configuration, after setting the output of the engine or motor first, the output of the hot water heater or electric heater is set on the output distribution line based on the output of the engine or motor. The output of the hot water heater or electric heater can be set so that the system efficiency is within an appropriate range with respect to the output of the motor. Thereby, the output of a hot water heating apparatus or an electric heating apparatus can be appropriately set with respect to the output of the engine or motor at that time, system efficiency can be improved, and fuel consumption can be improved.

  In the invention according to claim 2, the output of the engine (11) or the motor (12) in which the system efficiency is within a predetermined appropriate range with respect to the output of the hot water heater (22) or the electric heater (42). A configuration comprising control means (33) for setting the output of the engine (11) or the motor (12) corresponding to the output of the hot water heater (22) or the electric heater (42) on the connected output distribution line; It is a thing.

  In this configuration, after setting the output of the hot water heater or electric heater first, the output of the engine or motor is set on the output distribution line based on the output of the hot water heater or electric heater. The output of the engine or motor can be set so that the system efficiency falls within an appropriate range with respect to the output of the hot water heater or electric heater. Thereby, the output of an engine or a motor can be set appropriately with respect to the output of the hot water heater or electric heater at that time, the system efficiency can be improved, and the fuel efficiency can be improved. The invention according to claim 2 is effective in the case where the degree of freedom is high in the distribution of the traveling output such as during auto-cruise (cruise control) or the case where comfort is prioritized such as at the start of heating.

FIG. 1 is a diagram showing a schematic configuration of a hybrid vehicle control system in Embodiment 1 of the present invention. FIG. 2 is a flowchart showing the flow of processing of the output setting routine of the first embodiment. FIG. 3 is a block diagram illustrating a method for calculating the optimum HP output. FIG. 4 is a diagram for explaining a method for creating an optimum HP output distribution calculation map. FIG. 5 is a diagram conceptually illustrating an example of the optimum HP output distribution calculation map. FIG. 6 is a flowchart showing the flow of processing of the output setting routine of the second embodiment. FIG. 7 is a diagram conceptually illustrating an example of the HC output ratio calculation map. FIG. 8 is a block diagram illustrating a method for calculating the optimum MG output.

  Hereinafter, some embodiments embodying the mode for carrying out the present invention will be described.

A first embodiment of the present invention will be described with reference to FIGS.
First, a schematic configuration of a hybrid vehicle control system will be described with reference to FIG.
An engine 11 that is an internal combustion engine and a motor generator (hereinafter referred to as “MG”) 12 are mounted as power sources for the vehicle. The power of the output shaft (crankshaft) of the engine 11 is transmitted to the transmission 13 via the MG 12, and the power of the output shaft of the transmission 13 is transmitted to the wheels 16 via the differential gear mechanism 14, the axle 15 and the like. . The transmission 13 may be a stepped transmission that switches the shift speed step by step from a plurality of shift speeds, or may be a CVT (continuously variable transmission) that shifts continuously.

  A rotary shaft of the MG 12 is connected between the engine 11 and the transmission 13 in a power transmission path for transmitting the power of the engine 11 to the wheels 16 so that the power can be transmitted. Note that a clutch (not shown) for intermittently transmitting power may be provided between the engine 11 and the MG 12 (or between the MG 12 and the transmission 13).

  The main battery 18 is charged with the power generated by the generator 17 driven by the power of the engine 11. An inverter 19 that drives the MG 12 is connected to the main battery 18, and the MG 12 exchanges power with the main battery 18 via the inverter 19. The generator 17 is connected to the low voltage battery 21 via the DC-DC converter 20. The main battery 18 and the low-voltage battery 21 are both batteries that can be charged and discharged (charge and discharge are possible).

  Moreover, as a heating device for heating the vehicle interior, a hot water heating device 22 that uses heat of the cooling water of the engine 11 and an electric heating device 42 (heat pump device) that generates heat by electricity are mounted.

  In the hot water heater 22, a heating hot water circuit 23 is connected to a cooling water passage (not shown) of the engine 11, and a heating heater core 24 and an electric water pump 25 are provided in the hot water circuit 23. . The electric water pump 25 is driven by the electric power of the low-voltage battery 21, and the electric water pump 25 circulates cooling water (hot water) between the engine 11 and the heater core 24.

  The electric heating device 42 includes an electric compressor 37 that compresses a low-temperature and low-pressure gas refrigerant into a high-temperature and high-pressure gas refrigerant, and an indoor heat exchanger 38 that releases heat from the high-temperature and high-pressure gas refrigerant into a high-pressure liquid refrigerant. A condenser), an expansion valve 39 that expands the high-pressure liquid refrigerant under reduced pressure to form a low-temperature and low-pressure liquid refrigerant, and an outdoor heat exchanger 40 that absorbs heat into the low-temperature and low-pressure liquid refrigerant to form a low-temperature and low-pressure gas refrigerant ( An evaporator) and an accumulator 41 for separating the liquid refrigerant that has not been evaporated by the outdoor heat exchanger 40 and supplying only the gas refrigerant to the compressor 37.

  The electric compressor 37 is connected to the low voltage battery 21 via a compressor inverter (not shown). The air conditioner ECU 36 described later controls the compressor inverter by controlling the compressor inverter. A blower fan 26 that generates warm air is disposed in the vicinity of the heater core 24 and the indoor heat exchanger 38, and a radiator fan 27 is disposed in the vicinity of the outdoor heat exchanger 40.

  The accelerator sensor 28 detects the accelerator opening (the amount of operation of the accelerator pedal), and the shift switch 29 detects the operation position of the shift lever. Further, a brake operation (or a brake operation amount by a brake sensor) is detected by the brake switch 30, and a vehicle speed is detected by the vehicle speed sensor 31.

  The hybrid ECU 33 is a computer that comprehensively controls the entire vehicle, and reads the output signals of the various sensors and switches described above to detect the driving state of the vehicle. The hybrid ECU 33 includes an engine ECU 34 that controls the operation of the engine 11, an MG-ECU 35 that controls the inverter 19 to control the MG 12 and the generator 17, and heating devices 22 and 42 (the electric water pump 25, the blower Control signals, data signals, and the like are transmitted to and received from the air conditioner ECU 36 that controls the fan 26, the electric compressor 37, etc., and the ECUs 11, 36, 36, and the engine 11, MG 12, generator 17, heating The devices 22, 42 and the like are controlled.

  By the way, when the cooling water temperature of the engine 11 is low, there is a possibility that the cooling water temperature is further lowered only by the heating by the hot water heating device 22. In this case, if the engine 11 is forcibly operated in order to raise the temperature of the cooling water, the EV traveling that stops the combustion of the engine 11 and travels with the power of the MG 12 cannot be performed. Further, if the output of the electric heating device 42 is increased, the cooling water temperature can be prevented from decreasing. However, since electric power is consumed by the electric heating device 42, the distance that the EV can travel is shortened and the fuel consumption is deteriorated.

  In order to improve the fuel efficiency, it is required to use the heat effectively so that the heat of the cooling water is not insufficient, to minimize the output of the electric heating device 42, and to increase the EV travelable distance. Needs to set the output distribution of the hot water heater 22 and the electric heater 42 appropriately.

  Therefore, in the first embodiment, the hybrid ECU 33 executes an output setting routine of FIG. 2 to be described later, whereby the outputs of the engine 11 and MG 12 and the outputs of the hot water heater 22 (heater core 24) and the electric heater 42 are as follows. Set as follows. In the following description, the output of the engine 11 is expressed as “EG output”, and the output of the MG 12 is expressed as “MG output”. Further, the output of the hot water heater 22 (heater core 24) is expressed as “HC output”, and the output of the electric heater 42 is expressed as “HP output”.

First, an EG output and an MG output are set based on the required travel power of the vehicle.
Thereafter, the HP output corresponding to the MG output is set on the HP output distribution line that connects the HP output in which the system efficiency is within a predetermined appropriate range with respect to the MG output. In this case, in the first embodiment, the driving power of the vehicle, the amount of heating heat, the generated power of the MG 12 and the generator 17, the discharged power of the main battery 18 and the low-voltage battery 21, the amount of cooling water heating, the amount of heat dissipated in cooling water, and the fuel consumption power. The system efficiency function is defined using (the value obtained by multiplying the fuel consumption by the lower heating value of the fuel), and on the optimum HP output distribution line connecting the HP output that maximizes the system efficiency function with respect to the MG output. , HP output corresponding to MG output is set.

Thereafter, the HC output is set based on the required heating power of the vehicle and the HP output.
Thereby, the HC output and the HP output are set so that the system efficiency is within an appropriate range with respect to the EG output and the MG output at that time (in this embodiment, the system efficiency function is maximum).

Hereinafter, the processing content of the output setting routine of FIG. 2 executed by the hybrid ECU 33 in the first embodiment will be described.
The output setting routine shown in FIG. 2 is repeatedly executed at a predetermined period during the power-on period of the hybrid ECU 33, and serves as a control means in the claims.

  When this routine is started, first, in step 101, the required travel power of the vehicle (power required for traveling of the vehicle) is calculated by a map or a mathematical formula based on the accelerator opening or the like. Further, the required heating power (power required for heating the passenger compartment) is calculated based on the outside air temperature, the passenger compartment temperature, the target passenger compartment temperature, and the like using a map or a mathematical expression.

  Thereafter, the process proceeds to step 102, where the EG output and the MG output are set based on the required travel power. In this case, for example, the system efficiency function is defined using the travel request power, the generated power, and the discharge power without considering the heating request so that the system efficiency function is within a predetermined range including the maximum or the maximum. Set EG output and MG output. Alternatively, the charging / discharging power corresponding to the battery SOC (the charging state of the main battery 18 and the low voltage battery 21) is calculated from a map or the like, and the charging / discharging power is added to the traveling required power to calculate the required vehicle power. The engine 11 is turned on / off based on whether or not the vehicle required power is greater than the threshold value, and the EG output and the MG output are set. However, when the cooling water temperature is equal to or lower than a predetermined value when heating is on, EV traveling is prohibited and the engine 11 is operated.

  The EG output calculated in step 102 is set as the EG output commanded to the engine ECU 34, and the MG output calculated in step 102 is set as the MG output commanded to the MG-ECU 35.

  Thereafter, the process proceeds to step 103, and the HP output corresponding to the MG output is set on the optimum HP output distribution line connecting the HP output having the maximum system efficiency function with respect to the MG output. Specifically, as shown in FIG. 3, an optimum HP output corresponding to the travel required power, the required heating power, and the MG output is calculated using an optimal HP output distribution calculation map (see FIG. 5). The optimum HP output distribution calculation map is created in advance based on test data, design data, and the like, and is stored in the ROM of the hybrid ECU 33.

  The optimum HP output distribution calculation map is created as follows. First, the required travel power of the vehicle (travel power), the required heating power (heating heat per unit time), the generated power of the MG 12 and the generator 17, the discharged power of the main battery 18 and the low-voltage battery 21, and the cooling water heating power (unit) The system efficiency function is defined by the following formula (1) using the cooling water heating amount per hour) and the cooling water heat radiation power (cooling water heat radiation amount per unit time).

  Here, [-] means a dimensionless number. α is a weighting coefficient (for example, 1.0) of generated power, and β is a coefficient (for example, 0.3) for converting discharged power to fuel consumption power. Further, δ is a coefficient (for example, 0.2) for converting the cooling water radiation power into fuel consumption power, and γ is a weighting coefficient (for example, 1.0) of the cooling water heating power.

  As shown in FIG. 4, in this system efficiency function, the output distribution of the engine 11 and the MG 12 and the output distribution of the hot water heater 22 and the electric heater 42 are changed for each combination of the travel required power and the required heating power. A contour line (efficiency graph) of the system efficiency function is created, and an optimum HP output distribution line connecting the HP output that maximizes the system efficiency function with respect to the MG output is calculated. The optimum HP output distribution calculation map (see FIG. 5) is created using the data of the optimum HP output distribution line for each combination of the travel required power and the required heating power calculated in this way.

After calculating the optimum HP output, the optimum HC output is obtained by subtracting the optimum HP output from the required heating power.
Optimal HC output = Heating demand power-Optimal HP output

  Thereafter, the routine proceeds to step 104, where the predicted value of the future battery SOC is calculated by the following equation using the current battery SOC, MG output, HP input (power consumption of the electric heating device 42) and the SOC conversion coefficient K1. .

Battery SOC predicted value = current battery SOC + K1 × (−MG output−HP input)
Here, the SOC conversion coefficient K1 is the reciprocal of the battery output corresponding to 1% of the battery SOC. As the MG output, the MG output set in step 102 is used. The HP input (power consumption of the electric heating device 42) is calculated based on the HP output (optimum HP output) set in step 103 above.

  Further, the current cooling water temperature, the cooling water heating power of the engine 11 (cooling water heating amount per unit time), the cooling water heat dissipation power of the heater core 24 (cooling water heat dissipation amount per unit time), and the water temperature conversion coefficient K2 are used. Thus, the predicted value of the future cooling water temperature is calculated by the following equation.

Predicted cooling water temperature value = current cooling water temperature + K2 x (cooling water heating power-cooling water heat dissipation power)
Here, the water temperature conversion coefficient K2 is calculated from the cooling water amount and the specific heat of the cooling water. Further, the cooling water heating power of the engine 11 is calculated based on the EG output set in step 102 above. The cooling water radiating power of the heater core 24 is calculated based on the HC output (optimum HC output) set in step 103 above.

  Thereafter, the process proceeds to step 105, where it is determined whether or not the predicted battery SOC value is equal to or greater than a predetermined value and the predicted coolant temperature is equal to or greater than the predetermined value. Here, the predetermined value used for the determination of the battery SOC predicted value is set to a value slightly higher than the lower limit value (allowable lower limit value) of the battery SOC, for example. Moreover, the predetermined value used for the determination of the predicted coolant temperature is set to a value slightly higher than the lower limit (allowable lower limit) of the coolant temperature, for example.

If it is determined in step 105 that the predicted battery SOC value is equal to or greater than the predetermined value and the predicted coolant temperature is equal to or greater than the predetermined value, the process proceeds to step 106 to change the HP output commanded to the air conditioner ECU 36 to the optimal HP output. At the same time, the HC output commanded to the air conditioner ECU 36 is set to the optimum HC output.
HP output = optimum HP output
HC output = optimum HC output

  On the other hand, if it is determined in step 105 that the predicted battery SOC value is less than the predetermined value or the predicted coolant temperature is less than the predetermined value, the process proceeds to step 107, where the predicted battery SOC value is less than the predetermined value. It is determined whether or not.

  If it is determined in step 107 that the predicted battery SOC value is less than the predetermined value (including the case where the predicted battery SOC value is less than the predetermined value and the predicted coolant temperature is less than the predetermined value), the process proceeds to step 108. Then, the HP output and the HC output are set (corrected) so that the battery SOC does not fall below the lower limit value.

Specifically, the corrected HP output is calculated by the following equation using the margin to the battery SOC lower limit value (current battery SOC-battery SOC lower limit value), the SOC conversion coefficient K1, and the COP conversion coefficient K3. .
HP output after correction = margin to battery SOC lower limit / K1 x K3
Here, the COP conversion coefficient K3 is a coefficient for converting electric power into heat output (amount of heat per unit time).

Further, the corrected HC output is calculated by the following equation using the uncorrected HC output (optimum HC output), the uncorrected HP output (optimum HP output), and the corrected HP output.
HC output after correction = HC output before correction + (HP output before correction−HP output after correction)
The HP output and HC output calculated in step 108 are set as the HP output and HC output commanded to the air conditioner ECU 36.

  On the other hand, if it is determined in step 107 that the predicted coolant temperature is less than the predetermined value, the process proceeds to step 109, where HP output and HC output are set (corrected) so that the coolant temperature does not fall below the lower limit value. To do.

Specifically, the corrected HC output is calculated by the following equation using a margin (current cooling water temperature−cooling water temperature lower limit value) up to the cooling water temperature lower limit value and the water temperature conversion coefficient K2.
HC output after correction = margin to cooling water temperature lower limit / K2

Further, the corrected HP output is calculated by the following equation using the uncorrected HP output (optimum HP output), the uncorrected HC output (optimum HC output), and the corrected HC output.
HP output after correction = HP output before correction + (HC output before correction−HC output after correction)
The HP output and HC output calculated in step 109 are set as the HP output and HC output commanded to the air conditioner ECU 36.

  In the first embodiment described above, after setting the EG output and the MG output based on the required travel power, on the optimum HP output distribution line connecting the HP output that maximizes the system efficiency function with respect to the MG output, The HP output corresponding to the MG output is set, and the HC output is set by subtracting the HP output from the required heating power. Thereby, the system efficiency can be improved by appropriately setting the outputs of the hot water heater 22 and the electric heater 42 with respect to the outputs of the engine 11 and the MG 12 at that time. As a result, it is possible to suppress the forced operation of the engine 11 by suppressing the decrease in the coolant temperature, and to effectively use the amount of heat generated by the engine 11 to reduce the power consumption of the electric heating device 42 as much as possible. The distance that can be traveled can be increased, and fuel consumption can be improved. Further, the balance between the charge / discharge amount and the heat generation amount associated with traveling, the discharge amount and the heat release amount used for heating can be adjusted, and the battery SOC can be managed while effectively utilizing the cooling water heat.

  In the first embodiment, for example, when the optimum HP output distribution calculation map (see FIG. 5) is travel required power = 6 kW, heating required power = 3 kW, and MG output = 6 kW (MG output ratio = 100%), The optimum HP output is set to 2.4 kW (HP output ratio = 80%). In this case, EG output = 0 kW and HC output = 0.6 kW. As a result, when the required travel power is low (6 kW), the vehicle can travel as much as possible to improve fuel efficiency. Moreover, since there is no heat_generation | fever of the engine 11, the fall of a cooling water temperature can be suppressed by carrying 80% of heating request | requirement power with the electric heating apparatus 42. FIG.

  Further, the optimum HP output distribution calculation map shows that when the required travel power is 12 kW, the required heating power is 4 kW, and the MG output is -6 kW (MG output ratio = -50%), the optimal HP output is 0.6 kW (HP Output ratio = 16%). In this case, EG output = 18 kW and HC output = 3.4 kW. Thus, when the required traveling power is high (12 kW), the HC output is set to be high (3.4 kW) because the cooling water heating amount of the engine 11 is large. In addition, the MG output is set to a negative value (power generation side) and the MG 12 generates power (charges the battery 18) because the engine 11 is operated with higher efficiency due to an increase in load, and the battery SOC. It is for recovery. Furthermore, an electric heating device 42 is also used so as not to overuse the cooling water heat quantity.

  In the first embodiment, the HP output is set on the optimum HP output distribution line that connects the HP output that maximizes the system efficiency function with respect to the MG output. You may make it set HP output on the HP output distribution line which tied HP output with which a system efficiency function is in the predetermined range near the maximum with respect to MG output. Further, the system efficiency function is not limited to the system efficiency function described in the first embodiment, and the HP output distribution is obtained by connecting HP outputs in which the system efficiency calculated by another method is within an appropriate range (for example, within a predetermined range near the maximum or maximum) You may make it set HP output on a line. Alternatively, the HC output is set on the HC output distribution line connecting the HC outputs in which the system efficiency (including the system efficiency function) is within an appropriate range (for example, within a predetermined range near the maximum or maximum) with respect to the MG output. You may do it.

  Further, the HP output is set on the HP output distribution line connecting the HP outputs in which the system efficiency (including the system efficiency function) is within an appropriate range (for example, within a predetermined range near the maximum) with respect to the EG output. Anyway. Alternatively, the HC output is set on the HC output distribution line connecting the HC outputs in which the system efficiency (including the system efficiency function) is within an appropriate range (for example, within a predetermined range near the maximum or maximum) with respect to the EG output. You may do it.

  Next, a second embodiment of the present invention will be described with reference to FIGS. However, description of substantially the same parts as those in the first embodiment will be omitted or simplified, and different parts from the first embodiment will be mainly described.

  In the second embodiment, an EG output, an MG output, an HC output, and an HP output are set as follows by executing an output setting routine of FIG.

First, the HC output and the HP output are set based on the required heating power of the vehicle.
Thereafter, the MG output corresponding to the HP output is set on the MG output distribution line connecting the MG outputs whose system efficiency is within a predetermined appropriate range with respect to the HP output. At this time, in the second embodiment, the driving power of the vehicle, the heating heat amount, the generated power of the MG 12 and the generator 17, the discharge power of the main battery 18 and the low-voltage battery 21, the cooling water heating amount, and the cooling water heat dissipation amount are used. A system efficiency function is defined, and an MG output corresponding to the HP output is set on the optimum MG output distribution line connecting the MG outputs that maximize the system efficiency function with respect to the HP output.

Thereafter, the EG output is set based on the required traveling power of the vehicle and the MG output.
Thereby, the EG output and the MG output are set so that the system efficiency is within an appropriate range (the system efficiency function is maximum in this embodiment) with respect to the HC output and the HP output at that time.

Hereinafter, the processing content of the output setting routine of FIG. 6 executed by the hybrid ECU 33 in the second embodiment will be described.
The output setting routine shown in FIG. 6 is repeatedly executed at a predetermined cycle during the power-on period of the hybrid ECU 33, and serves as a control means in the claims.

  When this routine is started, first, in step 201, the required travel power of the vehicle is calculated based on the accelerator opening and the like by using a map or a mathematical expression. Further, the required heating power is calculated by a map or a mathematical formula based on the outside air temperature, the passenger compartment temperature, the target passenger compartment temperature, and the like.

  Then, it progresses to step 202 and sets HC output and HP output based on heating request power. Specifically, first, an HC output ratio corresponding to the battery SOC and the coolant temperature is calculated using an HC output ratio calculation map (see FIG. 7). The HC output ratio calculation map is created in advance based on test data, design data, and the like, and is stored in the ROM of the hybrid ECU 33. Thereafter, the heating request power is multiplied by the HC output ratio to obtain the HC output, and the HC output is subtracted from the heating request power to obtain the HP output.

HC output = heating required power x HC output ratio
HP output = heating required power−HC output The HC output and HP output calculated in step 202 are set as the HC output and HP output commanded to the air conditioner ECU 36.

  Thereafter, the process proceeds to step 203, and the MG output corresponding to the HP output is set on the optimal MG output distribution line connecting the MG output having the maximum system efficiency function with respect to the HP output. Specifically, as shown in FIG. 8, an optimal MG output corresponding to the travel required power, the required heating power, and the HP output is calculated using an optimal MG output distribution calculation map. The optimal MG output distribution calculation map is created in advance based on test data, design data, and the like, and is stored in the ROM of the hybrid ECU 33.

  The optimal MG output distribution calculation map is created as follows. In the system efficiency function, the output distribution of the engine 11 and the MG 12 and the output distribution of the hot water heating device 22 and the electric heating device 42 are changed for each combination of the required travel power and the required heating power, and the contour of the system efficiency function (efficiency graph) ) To calculate the optimum MG output distribution line connecting the MG outputs having the maximum system efficiency function with respect to the HP outputs. An optimal MG output distribution calculation map is created using the data of the optimal MG output distribution line for each combination of the travel required power and the required heating power calculated in this way.

After calculating the optimum MG output, the optimum EG output is obtained by subtracting the optimum MG output from the required travel power.
Optimal EG output = Traveling demand power-Optimal MG output

  Thereafter, the process proceeds to step 204, and the predicted value of the future battery SOC is calculated by the following equation using the current battery SOC, MG output, HP input (power consumption of the electric heating device 42) and the SOC conversion coefficient K1. .

Battery SOC predicted value = current battery SOC + K1 × (−MG output−HP input)
Here, the MG output (optimum MG output) set in step 203 is used as the MG output. The HP input (power consumption of the electric heating device 42) is calculated based on the HP output set in step 202 above.

Thereafter, the process proceeds to step 205, where it is determined whether or not the predicted battery SOC value is greater than or equal to a predetermined value. If it is determined in step 205 that the predicted battery SOC value is greater than or equal to a predetermined value, the process proceeds to step 206, where the MG output commanded to the MG-ECU 35 is set to the optimum MG output and commanded to the engine ECU 34. Set the EG output to the optimum EG output.
MG output = optimum MG output
EG output = optimum EG output

  On the other hand, if it is determined in step 205 that the predicted battery SOC value is less than the predetermined value, the process proceeds to step 207, where the MG output and the EG output are set (corrected) so that the battery SOC does not fall below the lower limit value. To do.

Specifically, the corrected MG output is calculated by the following equation using the margin to the battery SOC lower limit value (current battery SOC-battery SOC lower limit value), the SOC conversion coefficient K1, and the conversion coefficient K4.
MG output after correction = margin to battery SOC lower limit / K1 x K4
Here, the conversion coefficient K4 is a coefficient for converting electric power into a mechanical output.

Further, using the EG output before correction (optimum EG output), the MG output before correction (optimum MG output), and the corrected MG output, the corrected EG output is calculated by the following equation.
EG output after correction = EG output before correction + (MG output before correction−MG output after correction)

  The MG output calculated in step 207 is set as the MG output commanded to the MG-ECU 35, and the EG output calculated in step 207 is set as the EG output commanded to the engine ECU 34.

  In the second embodiment described above, after setting the HC output and the HP output based on the heating required power, on the optimum MG output distribution line connecting the MG output that maximizes the system efficiency function with respect to the HP output, The MG output corresponding to the HP output is set, and the EG output is set by subtracting the MG output from the travel required power. Thereby, the output of the engine 11 and the MG 12 can be appropriately set with respect to the outputs of the hot water heater 22 and the electric heater 42 at that time, the system efficiency can be improved, and the fuel efficiency can be improved. The second embodiment is effective when the degree of freedom is high in the distribution of traveling output, such as during auto-cruise (cruise control), or when comfort is prioritized such as at the start of heating.

  In the second embodiment, the MG output is set on the optimum MG output distribution line connecting the MG output that maximizes the system efficiency function with respect to the HP output. However, the present invention is not limited to this. For example, The MG output may be set on the MG output distribution line in which the MG output whose system efficiency function is within a predetermined range near the maximum is connected to the HP output. Furthermore, the MG output may be set on the MG output distribution line connecting the MG outputs in which the system efficiency calculated by another method is within an appropriate range (for example, within a predetermined range near the maximum or the maximum). Alternatively, the EG output is set on the EG output distribution line that connects the EG outputs in which the system efficiency (including the system efficiency function) is within an appropriate range (for example, within a predetermined range near the maximum) with respect to the HP output. You may do it.

  Further, the MG output is set on the MG output distribution line connecting the MG outputs in which the system efficiency (including the system efficiency function) is within an appropriate range (for example, within a predetermined range near the maximum) with respect to the HC output. Anyway. Alternatively, the EG output is set on the EG output distribution line connecting the EG outputs in which the system efficiency (including the system efficiency function) is within an appropriate range (for example, within a predetermined range near the maximum) with respect to the HC output. You may do it.

  In the first and second embodiments, the output setting routine is executed by the hybrid ECU. However, the present invention is not limited to this, and other ECUs (for example, an engine ECU, an MG-ECU, an air conditioner ECU, etc.) The output setting routine may be executed in at least one of them, or the output setting routine may be executed in both the hybrid ECU and another ECU.

  In addition, the present invention is not limited to the hybrid vehicle having the configuration shown in FIG. 1, and hybrid vehicles having various configurations (for example, a hybrid vehicle having a plurality of motor generators) in which an engine and a motor generator are mounted as a power source of the vehicle. The present invention can also be applied to a PHV vehicle (plug-in hybrid vehicle) that can charge a battery from a power source outside the vehicle.

  DESCRIPTION OF SYMBOLS 11 ... Engine, 12 ... MG (motor, generator), 17 ... Generator, 18 ... Main battery, 21 ... Low voltage battery, 22 ... Hot water heater, 33 ... Hybrid ECU (control means), 42 ... Electric heater

Claims (2)

An engine (11) and a motor (12) mounted as a power source of the vehicle; a generator (12, 17) driven by the engine (11); a chargeable / dischargeable battery (18, 21); In a hybrid vehicle control device comprising a hot water heater (22) that uses the heat of cooling water of the engine (11) and an electric heater (42) that generates heat by electricity,
On the output distribution line connecting the outputs of the hot water heating device (22) or the electric heating device (42) whose system efficiency is within a predetermined appropriate range with respect to the output of the engine (11) or the motor (12) The control means (33) for setting the output of the hot water heater (22) or the electric heater (42) corresponding to the output of the engine (11) or the motor (12) is provided. A hybrid vehicle control device. An engine (11) and a motor (12) mounted as a power source of the vehicle; a generator (12, 17) driven by the engine (11); a chargeable / dischargeable battery (18, 21); In a hybrid vehicle control device comprising a hot water heater (22) that uses the heat of cooling water of the engine (11) and an electric heater (42) that generates heat by electricity,
On the output distribution line that connects the output of the engine (11) or the motor (12) with a system efficiency within a predetermined appropriate range with respect to the output of the hot water heater (22) or the electric heater (42) The control means (33) for setting the output of the engine (11) or the motor (12) corresponding to the output of the hot water heater (22) or the electric heater (42) is provided. A hybrid vehicle control device.

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