JP5545284B2 - Air conditioning control device for vehicles - Google Patents

Description

  The present invention relates to a vehicle air conditioning control device.

  In recent years, various hybrid vehicles including an engine and a motor for driving the vehicle have been proposed and put into practical use. One of these is an electric vehicle (both series hybrid vehicles and range extender vehicles) in which a generator is driven by an engine to charge the battery and power is supplied from the battery to the driving motor and the driving wheels are driven by the driving motor. Say.) Is known. In this vehicle, the engine is used exclusively for power generation, and the power generated from the engine is not mechanically transmitted to the drive wheels.

  Generally, heating of the passenger compartment is performed using heat discarded from the engine to cooling water. Here, in the range extender vehicle, since the engine is exclusively for power generation, the engine is operated less frequently, and the amount of heat necessary for heating cannot be ensured only by exhaust heat of the engine. In view of this, it has been proposed that a range extender vehicle is equipped with an electric heater or a combustion heater as a heat generating device other than the engine, and the vehicle interior is heated using the heat generated by the heater and engine exhaust heat (for example, , See Patent Document 1). This Patent Document 1 discloses that the engine is not used for heating, and that heating is performed by a combustor (combustion heater).

Japanese Patent Laid-Open No. 09-11731

  However, in the vehicle disclosed in Patent Document 1, it is necessary to consume the fuel with the combustion heater to ensure the amount of heat for heating even when the vehicle travels a short distance or when the outside air temperature is not so low. The consumption of the fuel used for will increase. Also, if the heater alone is used to cover the heating heat under any cold conditions, it is necessary to install a heater having a large heating capacity that is assumed even under extreme cold conditions, and there is a concern that the cost will increase. . In particular, the configuration using a combustion heater is likely to have a problem that it is large and cost is increased as compared with the case where an electric heater is used.

  The main object of the present invention is to provide a vehicle air-conditioning control device that can reduce fuel consumption in a vehicle including a traveling motor and a power generation engine, and that can achieve this by using an inexpensive heater. It is what.

  Hereinafter, means for solving the above-described problems and the effects thereof will be described.

The present invention relates to a vehicle including a travel motor driven by power supply from a battery and a power generation engine driven to charge the battery, and an electric heater that generates heat by power supply from the battery; The present invention relates to a vehicle air-conditioning control apparatus that is applied to a vehicle air-conditioning system that has a heater core that is heated by exhaust heat from a power generation engine and generates heat, and that heats the interior of the vehicle by heat generated by the electric heater and the heater core. Further, the first configuration includes a required amount calculation means for calculating the required amount of heating when the vehicle interior heating is performed, and the heat generated by the electric heater based on the calculated required amount of vehicle interior heating. A first control means for performing heating, a heater heat generation determination means for determining whether or not the required amount can be satisfied by the generated heat when the electric heater is heated, and the heater heat generation determination means in the electric When it is determined that the required amount can be satisfied by heat generation of the heater, the operation of the power generation engine for heating the heater core is not performed, and the electric heater is heated in the heater heat generation determination means. And a second control means for heating the heater core by operating the power generation engine when it is determined that the required amount cannot be satisfied. .

  In the above configuration, when heating the passenger compartment, the heating control is made different depending on whether or not the required amount of heating in the passenger compartment can be satisfied by the heat generated by the electric heater. When the amount can be satisfied, the operation of the power generation engine for the purpose of heating the heater core is not performed, for example, the power generation engine is stopped. In this case, heating can be performed while the power generation engine is stopped, and fuel consumption can be suppressed by keeping the engine stopped. If the required amount cannot be satisfied even if the electric heater generates heat, the power generation engine is operated, the heater core is heated by engine exhaust heat, and the vehicle interior is heated by the heat generated by the heater core. At this time, the power generation engine is operated for heating (utilizing exhaust heat) only when the temperature is colder than originally assumed, for example, under extremely cold conditions. The fuel consumption is limited, and the fuel consumption can be reduced.

  Moreover, in the said structure, it is set as the structure which utilizes the waste heat of the engine for electric power generation as needed instead of being able to cover heating only with an electric heater under any cold condition. For this reason, it is not necessary to use an electric heater having a large heating capacity even in an extremely cold state, and the heating requirement can be satisfied by using a relatively inexpensive heater.

  As a method for determining whether or not the required amount can be satisfied by the heat generated by the electric heater, for example, the maximum amount of heat that can be generated by the electric heater is determined in advance, and the calculated required amount of heating in the vehicle interior Is larger than the maximum heat amount of the electric heater, it may be determined that the required amount cannot be satisfied due to the heat generated by the electric heater.

In the second configuration , the power generation engine is a water-cooled engine, and the heater core is heated by engine cooling water, and the temperature of the engine cooling water enables heating of the vehicle interior by the heater core. Water temperature determination means for determining whether or not the temperature is within a predetermined temperature range is provided, and the second control means determines that the required amount cannot be satisfied even if the electric heater is heated in the heater heat generation determination means. In this case, the heater core is heated by operating the power generation engine on condition that the temperature of the engine cooling water is determined not to be in the predetermined temperature range in the water temperature determination means.

  If the temperature of the engine cooling water is high to some extent and is in a predetermined temperature range (for example, 45 ° C. or higher), the vehicle interior can be heated by the heater core without the power generation engine being in an operating state. In view of this point, when the required amount of vehicle interior heating is relatively large and the required amount of vehicle interior heating cannot be satisfied even if the electric heater generates heat, the operation of the power generation engine is performed based on the temperature of the engine coolant. The heater core is heated by the above. In this case, unnecessary engine operation can be eliminated, and fuel consumption can be further reduced.

In the third configuration , the first control means in the second configuration is configured to adjust the amount of heat generated by the electric heater based on the temperature of the engine cooling water.

  When the temperature of the engine cooling water is relatively high and the vehicle interior can be heated by the heater core, the heating by the heat generation of the heater core can be performed in parallel with the heating by the heat generation of the electric heater. In this case, by using the heat of the engine coolant for heating, the heating burden by the electric heater can be reduced. Thereby, the power consumption by an electric heater can be reduced and the energy cost can be reduced.

In the fourth configuration , the vehicle calculates the remaining amount of electricity of the battery, and when the calculated remaining amount of electricity becomes equal to or less than a predetermined value, the vehicle is configured to charge the battery by operating the power generation engine. When the vehicle interior heating is performed, a heater drive restriction unit is provided that restricts the driving of the electric heater when the battery is charged.

  According to the above configuration, when the remaining amount of electricity in the battery is reduced, the driving of the electric heater is restricted, and the battery charging is performed with priority. Therefore, even in the above-described configuration in which the vehicle interior heating is basically performed by the heat generated by the electric heater, it is possible to suppress the inconvenience that the driving of the traveling motor is hindered due to the decrease in the remaining amount of electricity in the battery. . In addition, as a drive restriction | limiting of an electric heater, for example, it is possible to prohibit a heater drive, or to make a heater drive amount (energization amount) a very small amount. Further, when the battery is charged, the amount of exhaust heat (for example, engine water temperature) increases due to the operation of the power generation engine. Therefore, instead of heating by heat generated by the electric heater, heating by engine exhaust heat (heating by the heater core) is performed.

In the fifth configuration , the second control unit is configured to operate the power generation engine in the first operation mode while operating the power generation engine in the second operation mode when the battery is charged. In the operation mode, the power generation engine is operated in an engine operation state in which the engine output is lower than that in the second operation mode.

  According to the above configuration, when the required amount cannot be satisfied even if the electric heater generates heat, the power generation engine is operated in the first operation mode. In this case, since the first operation mode is an engine operation state in which the engine output is lower than the second operation mode, which is the engine operation state at the time of battery charging, the power generation amount (battery charging capacity) is small. However, the heater core can be heated by exhaust heat, and heating by the heater core can be promoted. It should be noted that the power generation amount in the first operation mode may be at least a power generation amount required for driving the electric heater.

In the sixth configuration , when the vehicle interior heating is performed, after the engine for power generation is operated and battery charging is started, the operation of the engine for power generation is stopped when the remaining amount of electricity rises to the first threshold value. On the other hand, when the vehicle interior heating is not performed, after the power generation engine is operated and battery charging is started, the operation of the power generation engine is stopped when the remaining amount of electricity rises to a second threshold value And the first threshold value is smaller than the second threshold value.

  According to the above configuration, the threshold for stopping the operation of the power generation engine after starting the battery charging by operating the power generation engine is different between when the vehicle interior heating is performed and when it is not performed, The “first threshold value” when the vehicle interior heating is performed is smaller than the “second threshold value” when the vehicle interior heating is not performed. As a result, when the vehicle interior heating is performed, the battery charging is terminated at an earlier stage than when the vehicle interior heating is not performed (normal time). In this case, when the vehicle interior heating is performed, the period in which the driving of the electric heater is restricted by giving priority to battery charging is reduced, which is advantageous in efficiently performing the vehicle interior heating.

The block diagram which shows the outline of the control system for vehicle air conditioning in embodiment of invention. The flowchart which shows the control processing of the heat_generation | fever and charge at the time of vehicle interior heating. The flowchart which shows a heating control process. The time chart which shows the control processing of the heat_generation | fever and charge at the time of vehicle interior heating. The figure which shows the control range of the remaining capacity at the time of vehicle interior heating in other embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. This embodiment is embodied in a control device for a vehicle air conditioning system of a hybrid vehicle (range extender vehicle) that includes a motor as a power source and an engine dedicated to power generation. In this system, an electronic control unit (hereinafter referred to as ECU) is used as a center to control a motor and an engine and to control air conditioning in the vehicle interior. FIG. 1 shows an overall schematic configuration diagram of this system.

  In FIG. 1, an engine 10 is a spark ignition type multi-cylinder gasoline engine and includes a throttle valve, an intake valve, an exhaust valve, a fuel injection valve, an ignition device, and the like. The exhaust passage 11 of the engine 10 is provided with a catalyst 12 for purifying CO, HC, NOx and the like in the exhaust, and the thermal energy (exhaust heat) contained in the exhaust is sent downstream from the catalyst 12. A heat recovery device 13 for recovery is provided. The heat recovery device 13 recovers the heat of the exhaust gas by transmitting it to the engine cooling water, and is used as a heat source when heating the interior of the vehicle, for example.

  Next, the configuration of the cooling system of the engine 10 will be described.

  A water jacket 14 is formed inside the cylinder block and the cylinder head of the engine 10, and cooling water is circulated and supplied to the water jacket 14 so that the engine 10 is cooled. The temperature of the cooling water in the water jacket 14 (cooling water temperature) is detected by a water temperature sensor 15. A circulation path 16 composed of a cooling water pipe or the like is connected to the water jacket 14, and a water pump 17 for circulating the cooling water is provided in the circulation path 16. The water pump 17 is, for example, a mechanical pump that is driven as the engine 10 rotates, but may be an electric pump. Moreover, the structure which can adjust the amount of cooling water with the water pump 17 may be sufficient.

  The circulation path 16 is provided on the outlet side of the engine 10 (water jacket 14) so as to extend toward the heater core 18 as a heat exchanging portion and return to the engine 10 again through the heat recovery device 13. The circulation path 16 is bifurcated in two directions on the upstream side of the heater core 18, and a radiator 21 as an atmospheric heat radiation portion is provided in one of the circulation paths 16 </ b> A. A radiator fan 23 that is rotationally driven by a DC motor or the like is provided in the vicinity of the radiator 21, and an air flow is formed in the vicinity of the radiator 21 by the driving of the radiator fan 23. In addition, a thermostat 22 that changes the flow path of the cooling water by operating according to the cooling water temperature is provided at a branch portion of the circulation path 16. When the cooling water is at a low temperature (below the thermostat operating temperature), the cooling water is prevented from flowing into the radiator 21, and the cooling water circulates in the circulation path 16 without being radiated by the radiator 21. . For example, before the engine 10 is warmed up (during warm-up operation), cooling (radiation) of cooling water in the radiator 21 is suppressed. On the other hand, when the cooling water reaches a high temperature (above the thermostat operating temperature), the cooling water is allowed to flow into the radiator 21, and the cooling water circulates in the circulation path 16 while being radiated by the radiator 21. Thereby, the cooling water is maintained at an appropriate temperature (for example, about 80 ° C.) under the engine operating condition.

  Next, the configuration of the air conditioner 30 will be described. The air conditioner 30 is disposed, for example, in the foremost part of the passenger compartment, and is configured such that a blower fan 19, an evaporator (evaporator) 32, a heater core 18, a PTC heater 33, and the like are accommodated in a casing 31.

  The casing 31 forms a passage 38 for air (air conditioned air) blown into the vehicle interior, and an air introduction port (not shown) for introducing air from outside or inside the vehicle is formed in the uppermost stream portion of the casing 31. Has been. In the casing 31, the blower fan 19 is disposed on the downstream side of the air inlet. The blower fan 19 is an electric blower driven by an electric motor. In this embodiment, the blower amount can be adjusted by the motor rotation speed.

  An evaporator 32 is disposed in the casing 31 on the downstream side of the blower fan 19. The evaporator 32 is a heat exchanger that performs heat exchange between the refrigerant flowing through the evaporator 32 and the conditioned air sent from the blower fan 19. The evaporator 32 is connected to a compressor (compressor) 35 and a condenser (condenser) 36 via a refrigerant pipe 34 and constitutes a refrigeration cycle together with the compressor 35 and the condenser 36.

  The compressor 35 sucks and compresses the refrigerant and discharges the refrigerant toward the evaporator 32. In the present embodiment, the compressor 35 is an electric type. The condenser 36 condenses the refrigerant discharged from the evaporator 32 by heat exchange between the refrigerant flowing through the condenser 36 and air blown from a fan (not shown) that is rotationally driven by a DC motor or the like. The refrigerant flowing out of the condenser 36 is gas-liquid separated by a receiver (not shown). Further, the separated liquid refrigerant is rapidly expanded by the expansion valve 37 to form a mist, and then supplied to the evaporator 32. In the evaporator 32, the refrigerant is vaporized by heat exchange between the conditioned air flowing through the passage 38 and the mist refrigerant, whereby the conditioned air flowing through the passage 38 is cooled.

  In the casing 31, the passage on the downstream side of the evaporator 32 is branched into a heating passage 39 and a cold air passage 41. Among them, the heater core 18 and the PTC heater 33 are disposed in the heating passage 39, and the conditioned air passing through the heating passage 39 is received by heat received from the heater core 18 (engine exhaust heat) and heat generated by the PTC heater 33. It is supposed to be heated.

  The PTC heater 33 is an electric heater that has a PTC element (positive characteristic thermistor) and generates heat when electric power is supplied to the PTC element. More specifically, the PTC heater 33 is composed of a plurality (three in this embodiment) of heating elements 33a, 33b, and 33c. In addition, switches SW1, SW2, and SW3 (not shown) are connected to each of the heating elements 33a, 33b, and 33c, and each switch SW1, SW2, and SW3 can be individually switched on / off. Thereby, the number of operating PTC heaters 33 to be energized, that is, the heating capacity of the PTC heaters 33 can be changed.

  A damper door 42 whose opening degree is adjusted by a damper door motor 54 is disposed on the passage entrance side of the heating passage 39 and the cold air passage 41. By adjusting the opening degree of the damper door 42 (damper opening degree), the air volume ratio between the air amount flowing through the heating passage 39 and the air amount flowing through the cold air passage 41 can be adjusted.

  In the casing 31, a mixing space 43 in which the air flowing through the heating passage 39 and the air flowing through the cold air passage 41 are mixed is formed on the outlet side of the heating passage 39 and the cold air passage 41. . Further, blowout ports 44, 45, and 46 for blowing the air in the mixing space 43 into the vehicle interior are disposed in the most downstream portion of the casing 31. In this embodiment, as the outlets 44, 45, 46, the face outlets 44, 46 that blow the conditioned air toward the upper body of the occupant in the vehicle interior and the foot outlet 45 that blows the conditioned air toward the feet of the occupant. Etc. are provided. Also, each of the air outlets 44, 45, 46 is provided with air volume adjusting doors 44a, 45a, 46a. By adjusting the opening degree of the air volume adjusting doors 44a, 45a, 46a, each air outlet opening 44a, 45a, 46a is adjusted. It is possible to adjust the amount of air blown into the vehicle compartment from 44, 45, 46.

  A motor MG1 as an auxiliary motor is connected to a crankshaft 47 that is an output shaft of the engine 10. The motor MG1 is a well-known synchronous generator motor that functions as both a generator and an electric motor. The motor MG1 generates electric power using the rotational energy of the crankshaft 47 and charges the battery 48 with the generated electric power. When the engine is started, the motor MG1 functions as an electric motor, and is driven by receiving power supplied from the battery 48 to apply initial rotation to the crankshaft 47 (motoring). An inverter INV1 is provided between the motor MG1 and the battery 48, and the rotational speed of the motor MG1 can be controlled by controlling the inverter INV1. The battery 48 can be charged by an external power source via the plug PG. The battery 48 is connected to a low-voltage battery (for example, a 12V auxiliary battery, not shown) via a DC-DC converter, and the low-voltage battery is charged by electric power from the battery 48.

  A motor MG2 as a main motor is connected to the battery 48 via an inverter INV2. The motor MG2 is a well-known synchronous generator motor that functions as both a generator and a motor. Wheels (drive wheels) 51 are connected to the motor MG2 via a speed reduction mechanism 49 and the like, and the power of the motor MG2 is transmitted to the drive wheels 51. The motor MG2 has a function of generating regenerative power when the vehicle decelerates, and charges the battery 48 with the generated power.

  In addition, the present system includes a crank angle sensor 52 that outputs a crank angle signal for each predetermined crank angle of the engine 10, a battery sensor 53 that detects a charge / discharge current of the battery 48, and an indoor temperature sensor 55 that detects a vehicle interior temperature Tr. In addition to the outside air temperature sensor 56 that detects the outside air temperature Tam and the evaporator temperature sensor 57 that detects the temperature Te of the conditioned air immediately after passing through the evaporator 32, the rotational positions of the rotors of the motors MG1 and MG2 are not shown. There are various sensors and switches such as a rotational position detection sensor for detecting the air conditioner, a blower switch for the operator to turn on / off the operation of the blower fan 19, and a temperature setting switch for the operator to set and input the vehicle interior temperature. Is provided. The evaporator temperature sensor 57 may be configured to detect the temperature of the heat exchange fins of the evaporator 32, for example, instead of the configuration of detecting the temperature of the conditioned air immediately after passing through the evaporator, and may be circulated in the evaporator 32. The structure which detects directly the temperature of the refrigerant | coolant to perform may be sufficient.

  As is well known, the ECU 60 is mainly composed of a microcomputer (hereinafter referred to as a microcomputer 61) composed of a CPU, ROM, RAM, and the like, and executes various control programs stored in the ROM, thereby performing various controls of the engine 10. The drive control of the motor MG1 and the motor MG2 is performed. Note that each of the motors MG1, MG2 and the engine 10 is actually controlled by a separate electronic control unit. Here, these electronic control units are represented as an ECU 60.

  In this embodiment, the engine 10 is dedicated to power generation, and the microcomputer 61 of the ECU 60 starts driving the fuel injection valve and the ignition device of the engine 10 and stops the operation of the engine 10 when the battery 48 is requested to be charged. The battery 48 is charged by switching from the state to the operation state. The presence / absence of the charge request for the battery 48 is determined based on, for example, a switch operation by the user or a remaining capacity SOC of the battery 48 calculated based on a detection value of the battery sensor 53.

  By the way, in the range extender vehicle, since the engine 10 is used exclusively for power generation, the frequency at which the engine 10 is in the operation stop state is high when a heating request is made. In such a case, if the engine 10 is switched from the operation stop state to the operation state every time a heating request is made and heating is performed using the engine exhaust heat, the fuel consumption of the engine 10 increases, and in terms of fuel consumption reduction. It is not preferable. On the other hand, if the PTC heater 33 alone is used to cover the required heating amount, it is necessary to mount a heater having a large heating capacity that is assumed even in extreme cold, and there is a concern about an increase in cost.

  Therefore, in the present embodiment, when the vehicle interior is heated, the contents of the heating control are made different depending on whether or not the required amount of vehicle interior heating can be satisfied by the heat generated by the PTC heater 33. Specifically, when the required amount of vehicle interior heating can be satisfied by the heat generated by the PTC heater 33, the engine 10 is not operated for the purpose of heating the heater core 18, and the engine 10 is left in an operation stopped state. Keep it. On the other hand, when the required amount of heating in the vehicle interior cannot be satisfied only by the heat generated by the PTC heater 33, the engine 10 is switched from the operation stop state to the operation state, and the vehicle interior heating is performed using the heat generated by the heater core 18 and the PTC heater 33. Do.

  FIG. 2 is a flowchart showing control processing of heat generation and charging during vehicle interior heating. This process is repeatedly executed by the microcomputer 61 of the ECU 60 at a predetermined cycle.

  In FIG. 2, first, in step S101, it is determined whether there is a request for heating and whether the blower fan 19 is in a blowing state. In this case, if step S101 is denied, it is considered that the subsequent heating process is unnecessary, and this process is terminated as it is. If step S101 is affirmed, the process proceeds to step S102 to perform the subsequent heating process.

  In step S102, it is determined whether or not the charge flag is zero. The charge flag is a flag indicating whether or not battery charging by the motor MG1 is performed. The charging flag = 0 indicates that battery charging is not performed, and the charging flag = 1 indicates that battery charging is performed. Indicates. Note that the charging flag is cleared to 0 when the initialization process is performed, such as when the IG key of the vehicle is turned on.

  When the charge flag = 0 (when step S102 is YES), the process proceeds to step S103, and it is determined whether or not the remaining capacity SOC of the battery 48 is less than a predetermined determination value Lo1. The determination value Lo1 is a threshold value for determining the start of battery charging, and is 20%, for example. If SOC ≧ Lo1, the process proceeds to step S104. In step S104, heating control using heat generated by the PTC heater 33 and engine exhaust heat is performed. Hereinafter, the heating control process of step S104 will be described with reference to FIG.

  In FIG. 3, in step S <b> 201, a heating required heat amount Q and a PTC operation number Nptc at the time of performing vehicle interior heating are calculated (required amount calculation means). The calculation procedure of the heating required heat quantity Q and the number of PTC operations Nptc is, for example, as follows.

(1) The target blowing temperature Tao is calculated by the following formula.
Tao = Ktset / Tset-Kr / Tr-Kam / Tam + C
Tset is a set temperature in the passenger compartment, Tr is a room temperature, and Tam is an outside air temperature. Further, Ktset, Kr, and Kam are gains for each of the above temperatures, and C is a constant.

(2) The temporary damper opening degree SW is calculated by the following equation.
SW = (Tao-Te) / (Tw-Te)
Te is the post-evaporator temperature, and Tw is the engine water temperature (= heater core temperature). The temporary damper opening degree SW is a mixing ratio necessary for realizing the target blowout temperature Tao. The small damper opening SW means that the necessity of heating the blown air in the heating passage 39 (heating by the PTC heater 33 or the heater core 18) is small.

  (3) The actual damper opening SW ′ is calculated. In the present embodiment, the actual damper opening degree SW ′ is controlled to either 1 or 0. If the temporary damper opening degree SW is larger than the predetermined value α, SW ′ = 1, and the temporary damper opening degree is set. If the degree SW is less than or equal to the predetermined value α, SW ′ = 0. When the actual damper opening degree SW ′ is thus calculated, the ECU 60 drives the damper door motor 54 based on the actual damper opening degree SW ′.

(4) The expected blowing temperature Taob is calculated by the following equation.
Taob = Te + SW ′ (Tw−Te)
(5) The heater undertemperature Tptc is calculated by the following equation.
Tptc = Tao-Taob
(6) The heating required heat quantity Q and the number of PTC operations Nptc are calculated by the following equations.
Q = Ga · ρa · Cp · Tptc
Nptc = Q / Kptc
Note that Ga is an air flow rate, ρa is an air density, Cp is a constant pressure specific heat, and Kptc is a reference heat generation amount in each of the heating elements 33a, 33b, and 33c of the PTC heater 33. The number of PTC operation Nptc is the number that operates (energizes) the heating elements 33a, 33b, and 33c in the PTC heater 33. In this embodiment, the PTC heater 33 is driven by the three heating elements 33a, 33b, and 33c as described above. The upper limit of the number of PTC operations Nptc is “3”.

  After calculating the heating required heat quantity Q and the number of PTC operations Nptc as described above, in step S202, an operation command is output for the PTC heater 33 (first control means). Here, if the engine water temperature is high, the heating required heat quantity Q may be borne by the heat quantity of the engine cooling water. In this embodiment, the number of operation commands for the PTC heater 33 is determined based on the engine water temperature. Yes. Specifically, the operation command number of the PTC heater 33 to be actually commanded is determined by setting the above PTC operation number Nptc as an upper limit and subtracting the operation stop number determined according to the engine water temperature from the upper limit. . In this case, the higher the engine water temperature, the smaller the number of operating PTC heaters 33 (that is, the smaller the PTC output), and the lower the engine water temperature, the larger the number of operating PTC heaters 33 (that is, the larger the PTC output). In addition, the drive of the PTC heater 33 is controlled.

  Thereafter, in step S203, when the PTC heater 33 is heated, whether the required heating amount Q can be satisfied by the generated heat, that is, whether the required heating amount Q can be satisfied only by driving the PTC heater 33 under the current conditions. (Heater heat generation determination means). Specifically, it is determined whether the heating required heat amount Q is larger than the maximum heat generation amount PTC_MAX of the PTC heater 33. If Q ≦ PTC_MAX, that is, if the heating required heat amount Q can be satisfied by the heat generated by the PTC heater 33, the process proceeds to step S204, the heat generation flag is cleared to 0, and the present process is terminated. The heat generation flag is a flag indicating whether or not heat generation by the engine 10 is being performed, that is, whether or not the engine 10 is in an operating state, and heat generation flag = 0 is heat generation being performed. No heat generation flag = 1 indicates that heat generation by the engine 10 is being performed.

  If Q> PTC_MAX, that is, if the heating required heat quantity Q cannot be satisfied even if the PTC heater 33 generates heat, the process proceeds to step S205, and it is determined whether the heat generation flag is 0 or not. At this time, if the engine is stopped and the heat generation flag = 0, the process proceeds to step S206, and it is determined whether or not the engine water temperature Tw is lower than the first determination value TWL (water temperature determination means). The first determination value TWL is a reference temperature on the lower limit side indicating that the heat of the engine coolant can be used as heat energy for heating. Therefore, Tw ≧ TWL means that heating of the passenger compartment by the heater core 18 is possible. In the present embodiment, for example, TWL = 45 ° C.

  When step S206 is negative (when Tw ≧ TWL), the present process is terminated, and when step S206 is positive (when Tw <TWL), the process proceeds to step S207. In step S207, 1 is set to the heat generation flag, and in subsequent step S208, the engine 10 is operated in the heat generation mode (second control means). This heat generation mode is an engine operation mode intended to use exhaust heat of the engine 10, and the engine output itself is smaller than that during engine operation in the charge mode. Specifically, the engine 10 is operated under the conditions of engine rotation speed = 2500 rpm and throttle opening = full open (WOT), the available heat is 5.8 kW, and the generated power is 3.6 kW. At this time, the power generation capability is not limited as long as it can generate at least the power consumed by the operation of the PTC heater 33. The heat generation mode corresponds to the first operation mode, and the charging mode corresponds to the second operation mode. Thereafter, this process is terminated.

  Further, when the heat generation flag is set to 1 as the engine 10 is operated, Step S205 is denied and the process proceeds to Step S209, where it is determined whether or not the engine coolant temperature Tw is larger than the second determination value TWH. The second determination value TWH is set to the temperature of the first determination value TWL + α, for example, TWH = 65 ° C.

  When step S209 is negative (when Tw ≦ TWH), the present process is terminated. When step S209 is positive (when Tw> TWH), the process proceeds to step S210. In step S210, the heat generation flag is cleared to 0, and in subsequent step S211, the operation of the engine 10 in the heat generation mode is stopped. Thereafter, this process is terminated.

  Returning to the description of FIG. 2, if it is determined in step S103 that SOC <Lo1, the process proceeds to step S105. In step S105, the charge flag is set to 1, and in the subsequent step S106, the operation of the PTC heater 33 is prohibited (heater drive limiting means). Then, in step S107, the engine 10 is operated in the charging mode. This charging mode is an engine operation mode for charging the battery 48, and the motor MG1 generates power with higher power generation efficiency than the heat generation mode described above. Specifically, the engine 10 is operated under the conditions of engine rotation speed = 3500 rpm, throttle opening = full open (WOT), available heat is 9.6 kW, and generated power is 5.3 kW.

  Further, after the charge flag is set to 1, step S102 is negative and the process proceeds to step S108. In step S108, it is determined whether or not the remaining capacity SOC of the battery 48 is larger than a predetermined determination value Lo2. The determination value Lo2 is a threshold value for determining the end of battery charging, and is 30%, for example. If SOC ≦ Lo2, the process is terminated as it is. If SOC> Lo2, the process proceeds to step S109. In step S109, the charge flag is cleared to 0, and in the subsequent step S110, the operation of the PTC heater 33 is permitted. In step S111, the operation of the engine 10 in the charging mode is stopped. Thereafter, this process is terminated.

  FIG. 4 is a time chart for more specifically explaining the operation of the heat generation and charging control process during vehicle interior heating. In FIG. 4, it is assumed that there is a request for heating throughout the entire period shown in the figure, and the blower fan 19 is in a blowing state (the blower switch is turned on).

  In FIG. 4, at the timing t1, the charge flag is 0, and the remaining capacity SOC of the battery 48 is equal to or greater than the determination value Lo1. Further, since the engine water temperature is relatively low, the PTC heater 33 has a Hi output. Here, the output of the PTC heater 33 is four-stage switching of Hi, Mid, Lo, and Off, and at the timing t1, the maximum output is the Hi output. Further, at the timing t1, even if the PTC heater 33 is heated, the heating requirement heat quantity Q cannot be satisfied by itself, so the engine 10 is operated in the heat generation mode (engine output = PWL). Thereafter, when the engine water temperature rises due to the operation of the engine 10 in the heat generation mode, the output of the PTC heater 33 is sequentially switched from Hi → Mid → Lo → Off in accordance with the water temperature rise.

  Then, the engine water temperature rises to the second determination value TWH at the timing t2, and the operation of the engine 10 is stopped. After the timing t2, the engine water temperature gradually decreases, and the output of the PTC heater 33 is sequentially switched in the order of Off → Lo → Mid → Hi. Thereafter, at timing t3, the engine water temperature decreases to the first determination value TWL, whereby the operation of the engine 10 in the heat generation mode is resumed. During the period from timing t1 to t4, the state where the charge flag is 0 and the remaining capacity SOC of the battery 48 is equal to or higher than the determination value Lo1 is maintained. The start and end of engine operation are repeatedly performed.

  When the remaining capacity SOC of the battery 48 becomes less than the determination value Lo1 at timing t4, the charging flag is set and the operation of the engine 10 in the charging mode is started. Further, the operation of the PTC heater 33 is stopped. After timing t4, battery charging is prioritized by stopping the operation of the PTC heater 33, and heating is performed by exhaust heat from the engine. After the timing t4, the remaining capacity SOC gradually increases, and when the remaining capacity SOC reaches the determination value Lo2 at the timing t5, the operation of the engine in the charging mode is stopped.

  After timing t5, the heating control using the heat generated by the PTC heater 33 and the engine exhaust heat is started again. Since the engine water temperature is sufficiently high at the timing t5, the operation of the PTC heater 33 is not started immediately, and the operation of the PTC heater 33 is started when the engine water temperature decreases to some extent. The subsequent operation is the same as the operation in the period from timing t1 to t4.

  Thereafter, at timing t6, as with timing t4, as the remaining capacity SOC of the battery 48 becomes less than the determination value Lo1, the charging flag is set and the operation of the engine 10 in the charging mode is started. Further, the operation of the PTC heater 33 is stopped.

  According to the embodiment described in detail above, the following excellent effects can be obtained.

  When heating the passenger compartment, if the required heat quantity Q can be satisfied by the heat generated by the PTC heater 33, the engine for the purpose of heating the heater core 18 until, for example, the outside air temperature drops below 0 ° C (or about ± 3 ° C). Thus, the heating operation is performed only by the heat generated by the PTC heater 33 without performing the operation 10. According to this configuration, heating can be performed while the engine 10 is stopped, and fuel consumption can be suppressed by keeping the engine 10 in a stopped state. Further, since the operation of the engine 10 can be reduced as much as possible when the vehicle interior heating is performed, the amount of CO2 emission can also be reduced.

  On the other hand, when heating the interior of the passenger compartment, if the required heat quantity Q cannot be satisfied due to the heat generated by the PTC heater 33, the engine 10 is switched to the operating state and the interior of the passenger compartment is heated by exhaust heat from the engine. . In this configuration, the engine 10 is operated for heating only in a limited situation, for example, under extremely cold conditions, so that the consumption of fuel for heating can be reduced.

  In addition, the PTC heater 33 alone is not able to cover heating under any cold conditions, but the exhaust heat of the engine 10 is used as necessary, so that the heater for heating is in an extremely cold state. It is not necessary to use what has the assumed large heating capacity. Therefore, a heating requirement can be satisfied using an inexpensive heater.

  When it is determined that the heating required heat quantity Q cannot be satisfied due to the heat generated by the PTC heater 33 during the heating of the passenger compartment, the temperature of the engine cooling water is not within a predetermined temperature range where the heater core 18 can heat the passenger compartment. The heater core 18 is heated by operating the engine 10 on the condition that it is determined as follows. According to this configuration, unnecessary engine operation can be eliminated, and fuel consumption can be further reduced.

  On the other hand, when the temperature of the engine cooling water is in a predetermined temperature range in which heating of the vehicle interior by the heater core 18 is possible, heating by heating of the heater core 18 can be performed in parallel with heating by heating of the PTC heater 33. . In view of this point, in the present embodiment, the amount of heat generated by the PTC heater 33 is adjusted based on the temperature of the engine coolant. By using the heat of the engine cooling water for heating, the heating burden by the PTC heater 33 can be reduced, and the power consumption by the PTC heater 33 can be reduced.

  When carrying out the vehicle interior heating, when the battery 48 is charged, the drive of the PTC heater 33 is limited. Specifically, when there is a heating request, the remaining capacity SOC of the battery 48 is the battery charge. The operation of the PTC heater 33 is prohibited when it is less than a predetermined determination value Lo1, which is a threshold value for determining start. Therefore, even in the present configuration in which the vehicle interior heating is basically performed by the heat generated by the PTC heater 33, it is possible to suppress inconvenience that the motor traveling is hindered due to the decrease in the remaining amount of electricity of the battery 48.

  When only the heat generated by the PTC heater 33 does not satisfy the heating required heat quantity Q and the engine 10 is put into an operating state, the engine operating state is set so that the engine output becomes lower than the engine operating state during battery charging. . In this case, although the power generation amount (battery charging capacity) is small, the heater core 18 can be heated by engine exhaust heat, and heating by the heater core 18 can be promoted.

(Other embodiments)
The present invention is not limited to the description of the above embodiment, and may be implemented as follows, for example.

  In the above embodiment, when the vehicle interior heating is performed in a state where the charge flag is 0 and the remaining capacity SOC of the battery 48 is equal to or greater than the determination value Lo1 (for example, the period from t1 to t4 in FIG. 4), When the engine water temperature rises to the second determination value TWH, the operation of the engine 10 is stopped (period t2 to t3 in FIG. 4), but this may be changed. For example, after the engine water temperature rises to the second determination value TWH, the engine 10 may be in an idle operation state and the engine operation may be continued. In short, after the engine water temperature has risen to the second determination value TWH, the engine exhaust heat does not have to be so large, and the fuel consumption of the engine 10 may be shifted to a relatively small state.

  In the above embodiment, the operation of the PTC heater 33 is stopped during the operation of the engine 10 in the charging mode (for example, the period from t4 to t5 in FIG. 4), but instead, the operation in the charging mode is performed. During operation of the engine 10, the heat generation amount of the PTC heater 33 (in other words, the power consumption by the PTC heater 33) may be limited to a predetermined minute amount.

  In the above embodiment, when the operation command is output for the PTC heater 33, the PTC operation number Nptc is set as the upper limit, and the operation stop number determined according to the engine water temperature is subtracted from the upper limit, whereby the operation of the PTC heater 33 is performed. Although the number of commands is increased or decreased (step S202 in FIG. 3), this may be changed. For example, the PTC heater number Nptc calculated in step S201 may be used as it is, that is, the heating by the PTC heater 33 may be performed without increasing or decreasing the engine water temperature.

  -You may make it the control range (range of a lower limit-upper limit) of remaining capacity SOC at the time of implementation of battery charge control differ between the time of implementation of vehicle interior heating, and the time of non-implementation. In this case, when the vehicle interior heating is performed, the control range of the remaining capacity SOC is set to a range on the low SOC side compared to when the vehicle interior heating is not performed, and thus the vehicle interior heating using the PTC heater 33 is actively performed. To do.

  Specifically, as shown in FIG. 5, each threshold value for battery charge control may be set variably. In FIG. 5, the period before the timing t11 is the heating non-execution period. In the non-execution period, the battery charge control is performed with the upper limit value Th1 and the lower limit value Th2. That is, when the remaining capacity SOC decreases to Th2, charging is performed by operating the engine 10, and thereafter, charging by operating the engine 10 is stopped when the remaining capacity SOC increases to Th1. In addition, after the timing t11 is an implementation period of heating, battery charge control is performed in the implementation period with the upper limit value as Th3 and the lower limit value as Th4. That is, when the remaining capacity SOC decreases to Th4, charging is performed by operating the engine 10, and thereafter, charging by operating the engine 10 is stopped when the remaining capacity SOC increases to Th3. At this time, Th3 <Th1, Th4 <Th2, and when the vehicle interior heating is performed, the vehicle in which the PTC heater 33 is actively used has priority over maintaining the remaining capacity SOC of the battery 48 in the high SOC range. Room heating is carried out. According to the above configuration, when the vehicle interior heating is performed, the period in which the driving of the PTC heater 33 is restricted by giving priority to battery charging is reduced, which is advantageous in efficiently performing the vehicle interior heating. Become.

  In the above embodiment, the case where the PTC heater 33 is used as the electric heater has been described. However, the present invention is not limited to this as long as heat is generated by power supply from the battery 48. For example, a resistance heating method, an induction heating method, etc. A heater can be employed.

  DESCRIPTION OF SYMBOLS 10 ... Engine (power generation engine), 13 ... Heat recovery device, 14 ... Water jacket, 18 ... Heater core, 19 ... Blower fan, 21 ... Radiator, 30 ... Air conditioner, 32 ... Evaporator, 33 ... PTC heater (electric heater) ), 33a, 33b, 33c ... heating element, 35 ... compressor, 36 ... condenser, 39 ... heating passage, 42 ... damper door, 47 ... crankshaft, 60 ... ECU (required amount calculation means, first control means, heater heat generation) Determination means, second control means, water temperature determination means, heater drive restriction means), 61... Microcomputer, MG1... Motor, MG2.

Claims (4)

In a vehicle comprising a traveling motor driven by power supply from a battery and a power generation engine driven for charging the battery, an electric heater that generates heat by power supply from the battery, and the power generation engine A vehicle air conditioning control device applied to a vehicle air conditioning system that has a heater core that is heated by exhaust heat and generates heat, and that heats the interior of the vehicle by heat generated by the electric heater and the heater core,
The vehicle calculates a remaining amount of electricity in the battery, and has a charging function for charging the battery by operating the power generation engine when the calculated remaining amount of electricity becomes a predetermined value or less. By stopping the operation of the power generation engine when the remaining amount of electricity is greater than or equal to a predetermined value after starting the battery charging by operating the engine for the engine, the remaining amount of electricity is within a predetermined control range,
A required amount calculating means for calculating a required amount of the heating when the vehicle interior heating is performed;
First control means for performing heating of the vehicle interior by heat generation of the electric heater based on the calculated required amount of vehicle interior heating;
Heater heating determination means for determining whether the required amount can be satisfied by the generated heat when the electric heater is heated;
When the heater heat generation determination unit determines that the required amount can be satisfied by the heat generation of the electric heater, the heater heat generation determination unit does not operate the power generation engine to heat the heater core. A second control means for operating the power generation engine to heat the heater core when it is determined that the required amount cannot be satisfied even if the electric heater generates heat;
Heater driving limiting means for limiting the driving of the electric heater when charging the battery when performing vehicle interior heating;
Equipped with a,
During implementation of the passenger compartment heating, the control range vehicular air conditioning control apparatus according to claim be relocated to a lower side than that in the non-execution of the passenger compartment heating a. The power generation engine is a water-cooled engine, and the heater core is heated by engine cooling water.
Water temperature determination means for determining whether or not the temperature of the engine cooling water is within a predetermined temperature range in which heating of the vehicle interior by the heater core is possible;
In the case where it is determined in the heater heat generation determination unit that the required amount cannot be satisfied even if the electric heater generates heat, the second temperature control unit determines that the engine cooling water temperature is the predetermined temperature in the water temperature determination unit. The vehicle air conditioning control device according to claim 1, wherein the heater core is heated by operating the power generation engine on condition that it is determined not to be in an area.   The vehicle air conditioning control device according to claim 2, wherein the first control unit adjusts a heat generation amount of the electric heater based on a temperature of the engine cooling water. In the second control means, the power generation engine is operated in the first operation mode, and the power generation engine is operated in the second operation mode when the battery is charged.
In the first operation mode, the vehicle air conditioning control according to any one of claims 1 to 3 to operate the generator engine with an engine operating condition in which the engine output becomes lower output than that of the second operating mode apparatus.

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