Heating control method for hybrid vehicles and heating control device for hybrid vehicles

Abstract

By preventing the release of thermal energy from the coolant through the radiator during winter heating, heating efficiency is improved, thereby enhancing the fuel economy of hybrid vehicles. [Solution] The hybrid vehicle 1 heats the cabin by raising the temperature of the coolant using the heat output of the heat pump 15 and the amount of heat dissipated by the engine 3, and cools the cabin by circulating the coolant to the radiator 45. When the engine 3 is driven while the heat pump 15 is being driven by the controller 21, the heat pump 15 is stopped, and when the temperature of the coolant rises above the engine stop temperature, which is lower than the switching temperature at which the coolant is circulated to the radiator 45, due to the amount of heat dissipated by the engine 3, the engine 3 is stopped.

Description

Technical Field

[0001] The present invention relates to a heating control method for a hybrid vehicle and a heating control device for a hybrid vehicle.

Background Art

[0002] Conventionally, a control device for a hybrid vehicle having an engine and an electric motor as power sources is disclosed in Patent Document 1. In the control device disclosed in Patent Document 1, when the temperature of the cooling water decreases and forced driving of the engine is estimated, the engine is driven in advance to increase the temperature of the cooling water and avoid forced driving of the engine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above-described conventional control device, since the temperature of the cooling water is raised in advance, there is a case where the thermostat opens and the thermal energy of the cooling water is released from the radiator. During heating in winter, since the thermal energy of the cooling water is used for heating, if it is released from the radiator, there is a problem that the heating efficiency decreases and the fuel consumption of the hybrid vehicle decreases.

[0005] An object of the present invention is to provide a heating control method for a hybrid vehicle and an apparatus thereof that can improve the heating efficiency and improve the fuel consumption of the hybrid vehicle by preventing the thermal energy of the cooling water from being released from the radiator during heating in winter.

Means for Solving the Problems

[0006] A heating control method and apparatus for a hybrid vehicle according to one aspect of the present invention, when the heating system is driven to heat the interior of the vehicle, if the internal combustion engine is driven, the heating system is stopped, and if the amount of heat emitted by the internal combustion engine causes the temperature of the coolant to rise above the internal combustion engine stop temperature, which is lower than the switching temperature at which the coolant is circulated to the outdoor heat exchanger, the internal combustion engine is stopped. [Effects of the Invention]

[0007] According to the present invention, it is possible to prevent the release of thermal energy from the coolant from the radiator during heating in winter, thereby improving heating efficiency and thus improving the fuel efficiency of hybrid vehicles. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 shows the configuration of the powertrain of a hybrid vehicle according to one embodiment. [Figure 2] Figure 2 is a flowchart showing the processing procedure for heating control processing during startup of a hybrid vehicle by a controller according to one embodiment. [Figure 3] Figure 3 is a time chart showing an example of heating control processing during startup of a hybrid vehicle by a controller according to one embodiment. [Figure 4] Figure 4 is a flowchart showing the processing procedure for heating control processing during normal heating by a controller according to one embodiment. [Figure 5] Figure 5 is a time chart showing an example of heating control processing during normal heating by a controller according to one embodiment. [Figure 6A] Figure 6A is a flowchart showing the processing procedure for heating control when the heating load is large, using a controller according to one embodiment. [Figure 6B] Figure 6B is a flowchart showing the processing procedure for heating control when the heating load is large, using a controller according to one embodiment. [Figure 7]Figure 7 is a time chart showing an example of heating control processing when the heating load is large by a controller according to one embodiment. [Modes for carrying out the invention]

[0009] The heating control method and apparatus for a hybrid vehicle according to this embodiment will be described below with reference to the drawings. In the drawings, the same parts are denoted by the same reference numerals, and detailed descriptions are omitted.

[0010] [Powertrain Configuration] Referring to Figure 1, the configuration of the powertrain of the hybrid vehicle according to this embodiment will be described. Figure 1 is a diagram showing the configuration of the powertrain of the hybrid vehicle. As shown in Figure 1, the hybrid vehicle 1 includes an engine 3, a motor generator 5, an inverter 7, a motor generator 9, an inverter 11, a battery 13, a heat pump 15, and a cooling system 17. The hybrid vehicle 1 also includes a controller 21, motor controllers 23 and 25, and a battery controller 27.

[0011] Hybrid vehicle 1 is equipped with an engine 3 and a motor generator 9 as its power source. The engine 3 drives the motor generator 5 to generate electricity, charges the battery 13 with the generated electricity, and drives the motor generator 9 with the electricity stored in the battery 13 to propel the vehicle. In addition, hybrid vehicle 1 uses the heat output of the heat pump 15 and the heat dissipation amount of the engine 3 to raise the temperature of the coolant to heat the passenger compartment, and circulates the coolant through the radiator 45 of the cooling system 17 to cool it.

[0012] Engine 3 is an internal combustion engine, such as a gasoline engine or a diesel engine, and drives the motor generator 5. The coolant of engine 3 circulates through the cooling system 17 and is used for heating the vehicle interior.

[0013] The motor generator 5 is provided on the output shaft of the engine 3 to generate electricity, and the generated electric power is charged to the battery 13 via the inverter 7. The inverter 7 converts the AC power output from the motor generator 5 into DC power and supplies it to the battery 13.

[0014] The motor generator 9 drives the drive wheels T when the power of the battery 13 is supplied via the inverter 11. The inverter 11 converts the DC power supplied from the battery 13 into AC power and supplies it to the motor generator 9.

[0015] The battery 13 is connected to the motor generators 5 and 9 via the inverters 7 and 11, and is charged by the electric power generated by the motor generator 5 and the electric power regenerated by the motor generator 9. Also, the battery 13 supplies electric power for running to the motor generator 9 and supplies electric power for heating to the heat pump 15.

[0016] The heat pump 15 is a heating device driven by the power of the battery 13, and includes a compressor 31, a water-cooled condenser 33, an expansion valve 35, and an outdoor heat exchanger 37, which are connected by a refrigerant passage 39 respectively. In the heat pump 15, the expansion valve 35 reduces the pressure of the refrigerant to lower the temperature, the outdoor heat exchanger 37 absorbs heat from the atmosphere to raise the temperature of the refrigerant, and the compressor 31 compresses the refrigerant to further raise the temperature. Then, in the water-cooled condenser 33, heat exchange is performed between the refrigerant with increased temperature and the cooling water of the engine 3 to raise the temperature of the cooling water.

[0017] The cooling system 17 is a system for cooling the cooling water of the engine 3, and includes a thermostat 41, a water-cooled condenser 33, an air conditioning control (HVAC) unit 43, a radiator 45, and a temperature sensor 47, which are connected by a cooling water passage 48 respectively. The air conditioning control unit 43 includes a heater core 49 and a fan 51.

[0018] The thermostat 41 regulates the flow of the cooling water flowing out from the engine 3. When the temperature of the cooling water becomes equal to or higher than a predetermined switching temperature, the thermostat 41 regulates the flow of the cooling water so that the cooling water circulates to the radiator 45. On the other hand, when the temperature of the cooling water is lower than the switching temperature, the thermostat 41 regulates the flow of the cooling water so that the cooling water does not circulate to the radiator 45. The switching temperature is set to a temperature at which the cooling water is circulated to the radiator 45.

[0019] The air-conditioning control unit 43 performs air conditioning in the passenger compartment of the hybrid vehicle 1. In the present embodiment, the case of performing heating in particular will be described. The radiator 45 is an outdoor heat exchanger that cools the cooling water of the engine 3, and reduces the temperature of the cooling water by performing heat exchange between the cooling water circulating inside and the air in the atmosphere.

[0020] In the cooling system 17, the cooling water whose temperature has risen in the engine 3 further rises in temperature in the water-cooled condenser 33 and then flows into the air-conditioning control unit 43. In the air-conditioning control unit 43, the inflowing cooling water exchanges heat with the air blown from the fan 51 in the heater core 49, and the air whose temperature has risen is sent into the passenger compartment to perform heating in the passenger compartment. That is, the heating in the passenger compartment is performed by raising the temperature of the cooling water by the heat radiation output of the heat pump 15 and the heat radiation amount of the engine 3. The cooling water that has passed through the air-conditioning control unit 43 is detected for its temperature by the temperature sensor 47 and then returns to the engine 3. When the temperature of the cooling water detected by the temperature sensor 47 rises to the switching temperature, the thermostat 41 opens the valve to circulate the cooling water to the radiator 45.

[0021] The controller 21 is a power train controller that controls the power train of the hybrid vehicle 1, and functions as a heating control device that particularly controls the heating in the passenger compartment of the hybrid vehicle 1. Specifically, the controller 21 raises the temperature of the cooling water by the heat radiation output of the heat pump 15 and the heat radiation amount of the engine 3 to perform heating in the passenger compartment, and circulates the cooling water to the radiator 45 for cooling.

[0022] The controller 21 consists of general-purpose electronic circuits including a microcomputer, microprocessor, and CPU, as well as peripheral devices such as memory, and has a computer program installed for performing heating control processing. Each function of the controller 21 can be implemented by one or more processing circuits. The processing circuits include, for example, programmed processing devices including electrical circuits, and also devices such as application-specific integrated circuits (ASICs) or conventional circuit components arranged to perform the functions described in the embodiments.

[0023] The motor controller 23 controls the motor generator 5 via the inverter 7 according to the control of the controller 21. The motor controller 25 controls the motor generator 9 via the inverter 11 according to the control of the controller 21. The battery controller 27 controls the charging and discharging of the battery 13 according to the control of the controller 21.

[0024] [Heating control processing during startup of hybrid vehicles] Next, the heating control process performed by the controller 21 according to this embodiment during the startup of the hybrid vehicle 1 will be described. Figure 2 is a flowchart showing the processing procedure for the heating control process during the startup of the hybrid vehicle 1, and Figure 3 is a time chart showing an example of the heating control process during the startup of the hybrid vehicle 1. The heating control process shown in Figures 2 and 3 starts when the power to the hybrid vehicle 1 is turned ON.

[0025] As shown in Figure 2, in step S101, the controller 21 determines whether or not a request to start the engine 3 has been output based on the energy management control. The energy management control controls the power state of the hybrid vehicle 1 according to the State of Charge (SOC) of the battery 13, and requests the start of the engine 3 as needed. If a request to start the engine 3 is output, the process proceeds to step S103; if no request to start the engine 3 is output, the process continues to determine whether or not a start request has been output.

[0026] In step S103, the controller 21 determines whether the temperature of the engine 3's coolant is lower than the minimum starting temperature. The minimum starting temperature is the lowest temperature required to start the engine 3, for example, 10°C. If the coolant temperature is lower than the minimum starting temperature, the process proceeds to step S105; if the coolant temperature is equal to or higher than the minimum starting temperature, the process proceeds to step S109.

[0027] In step S105, the controller 21 drives the heat pump 15 when the hybrid vehicle 1 is started because the coolant temperature is lower than the minimum starting temperature. Here, the heat pump 15 is driven at maximum output. For example, as shown in Figure 3, at time t0, when a request to start the engine 3 is output, the coolant temperature is lower than the minimum starting temperature of 10°C, so the heat dissipation output of the heat pump 15 is driven at maximum output Pm. At this time, the engine 3 is not running, so the total heating output is also Pm.

[0028] In step S107, the controller 21 determines whether the temperature of the coolant has risen to above the minimum starting temperature as a result of driving the heat pump 15. If the temperature of the coolant is above the minimum starting temperature, the process proceeds to step S109. If the temperature of the coolant remains below the minimum starting temperature, the controller 21 continues to determine whether it has risen above the minimum starting temperature.

[0029] In step S109, the controller 21 detects in step S107 that the coolant temperature has risen above the minimum starting temperature, and therefore starts the engine 3. For example, as shown in Figure 3, at time t1, the coolant temperature reaches the minimum starting temperature of 10°C, so the engine 3 starts and the engine speed increases. At this time, the engine 3 outputs a heat output of Pe, and the heat pump 15 is driven at its maximum output Pm, so the total heating output increases to Pm + Pe.

[0030] In step S111, the controller 21 determines whether the temperature of the engine 3's coolant is equal to or above the heating requirement temperature. The heating requirement temperature is the lower limit of the coolant temperature required for heating the passenger compartment, for example, 65°C. If the coolant temperature is equal to or above the heating requirement temperature, the process proceeds to step S113. If the coolant temperature is lower than the heating requirement temperature, the process continues to determine whether the coolant temperature is equal to or above the heating requirement temperature.

[0031] In other words, through the processing in steps S109 and S111, when the coolant temperature reaches or exceeds the minimum starting temperature, the controller 21 drives the engine 3 to raise the coolant temperature to the heating requirement temperature using the heat output of the heat pump 15 and the amount of heat dissipated by the engine 3.

[0032] In step S113, the controller 21 stops the heat pump 15. In step S111, it was detected that the cooling water temperature was above the heating requirement temperature, so the controller 21 stops the heat pump 15, which is being driven at maximum output. For example, as shown in Figure 3, at time t2, the cooling water temperature reaches the heating requirement temperature of 65°C, so the heat pump 15 is stopped and the heat output of the heat pump 15 becomes 0. At this time, the engine 3 is being driven at a heat output of Pe, so the total heating output is equal to the heat output of the engine 3, Pe, and the cooling water temperature continues to rise.

[0033] Thus, if the coolant temperature is low when the hybrid vehicle 1 is started, the heat pump 15 and engine 3 are driven to raise the coolant temperature to above the heating requirement temperature, and the heating control process at startup of the hybrid vehicle 1 according to this embodiment is terminated.

[0034] [Heating control processing during normal heating] Next, the heating control process by the controller 21 according to this embodiment during normal heating will be described. Figure 4 is a flowchart showing the processing procedure of the heating control process during normal heating, and Figure 5 is a time chart showing an example of the heating control process during normal heating. The heating control process shown in Figures 4 and 5 starts when the temperature of the engine 3's coolant rises above the heating requirement temperature, as shown in the flowchart of Figure 2. Furthermore, the heating control process of this embodiment is performed during normal heating when the outside temperature is 5 to 10°C and the heating load is moderate.

[0035] As shown in Figure 4, in step S201, the controller 21 determines whether or not a request to start the engine 3 has been output based on the energy management control. If a request to start the engine 3 has been output, the process proceeds to step S203. On the other hand, if a request to start the engine 3 has not been output, the controller 21 continues to determine whether or not a request to start the engine 3 has been output.

[0036] In step S203, the controller 21 determines whether the pre-set assumed heat output of the engine 3 is equal to or greater than the currently requested heating heat output. The heating heat output is the amount of heat required to heat the vehicle interior as requested. If the assumed heat output is equal to or greater than the heating heat output, the process proceeds to step S205. On the other hand, if the assumed heat output is less than the heating heat output, the heat output of the engine 3 alone is insufficient, and the heating control process during normal heating according to this embodiment is terminated in order to perform the heating control process for cases with a large heating load, which will be described later.

[0037] In step S205, the controller 21 starts the engine 3 in accordance with the engine start request output in step S201.

[0038] In step S207, the controller 21 determines whether the heat pump 15 is running or not. If it is running, the process proceeds to step S209; otherwise, the process proceeds to step S211.

[0039] In step S209, the controller 21 stops the heat pump 15. For example, as shown in Figure 5, when a request to start the engine 3 is output at time t3, the engine 3 starts and its rotational speed increases, and the engine 3 outputs a heat output amount Pe, which is the expected heat output. At this time, the heat pump 15 is driven by the heating request amount PN, but the heat output Pe from the engine 3 alone can exceed the heating request amount PN, so the heat pump 15 is stopped. Therefore, the total value of the heating output increases from PN to Pe at time t3. In other words, when the engine 3 is started while the heat pump 15 is being driven to heat the vehicle interior, the controller 21 stops the heat pump 15.

[0040] In step S211, the controller 21 determines whether the temperature of the engine 3's coolant is above the engine stop temperature, which is lower than the switching temperature of the thermostat 41. The switching temperature is the temperature at which the thermostat 41 opens and circulates the coolant to the radiator 45, for example, 90°C. The engine stop temperature is a temperature lower than the switching temperature and preset to stop the engine 3, for example, 85°C.

[0041] When the coolant temperature rises to the switching temperature, the coolant will circulate to the radiator 45. Therefore, by setting the engine stop temperature to a temperature lower than the switching temperature, the coolant is prevented from circulating to the radiator 45. If the coolant temperature of engine 3 is above the engine stop temperature, the process proceeds to step S213; otherwise, it proceeds to step S215.

[0042] In step S213, the controller 21 stops the engine 3. Specifically, the controller 21 stops the engine 3 when the amount of heat dissipated by the engine 3 causes the coolant temperature to rise above the engine stop temperature, which is lower than the switching temperature. This prevents the coolant temperature from rising further and reaching the switching temperature. The controller 21 also stops the engine 3 if a request to stop the engine 3 is output based on the energy management control.

[0043] For example, as shown in Figure 5, at time t4, the coolant temperature reaches the engine stop temperature of 85°C, so engine 3 stops, the engine speed becomes 0, and the heat dissipation from engine 3 also becomes 0. At this time, the heat pump 15 also stops, so the total heating output also becomes 0. Therefore, the coolant temperature decreases over time after time t4.

[0044] In step S215, the controller 21 determines whether the temperature of the engine 3's coolant is below the heating requirement temperature. If the coolant temperature is below the heating requirement temperature, the process proceeds to step S217; if it is above the heating requirement temperature, the process proceeds to step S219.

[0045] In step S217, the controller 21 starts the heat pump 15. At this time, the heat pump 15 is driven so that its heat output is equal to the required heating amount. As a result, the temperature of the cooling water is maintained at or above the required heating temperature. In other words, the controller 21 drives the heat pump 15 so that the temperature of the cooling water is maintained at or above the required heating temperature.

[0046] For example, as shown in Figure 5, at time t5, when the cooling water temperature drops to the heating requirement temperature of 65°C, the controller 21 drives the heat pump 15 with the heating requirement heat amount PN. At this time, since the engine 3 is stopped, the total heating output also becomes PN. As a result, the cooling water temperature is maintained at or above the heating requirement temperature of 65°C.

[0047] In step S219, the controller 21 determines whether the power to the hybrid vehicle 1 is turned off. If the power is not turned off, the process returns to step S201. On the other hand, if the power is turned off, the heating control process during normal heating according to this embodiment is terminated.

[0048] [Heating control process when heating load is high] Next, the heating control process by the controller 21 according to this embodiment when the heating load is large will be described. Figures 6A and 6B are flowcharts showing the processing procedure for heating control when the heating load is large, and Figure 7 is a time chart showing an example of heating control when the heating load is large. The heating control process shown in Figures 6A, 6B, and 7 starts when the assumed heat output becomes lower than the required heating amount and the process ends, as shown in the flowchart of Figure 4. Furthermore, the heating control process of this embodiment is performed when the outside temperature is below 5°C or when the heating load is large when warming up the vehicle interior.

[0049] As shown in Figure 6A, in step S301, the controller 21 determines whether or not a request to start the engine 3 has been output based on the energy management control. If a request to start the engine 3 has been output, the process proceeds to step S303. On the other hand, if a request to start the engine 3 has not been output, the controller 21 continues to determine whether or not a request to start the engine 3 has been output.

[0050] In step S303, the controller 21 starts the engine 3 in accordance with the engine start request output in step S301.

[0051] In step S305, the controller 21 determines whether the heat pump 15 is stopped or not. If it is stopped, the process proceeds to step S307; otherwise, the process proceeds to step S309.

[0052] In step S307, the controller 21 starts the heat pump 15 because the amount of heat dissipated by the engine 3 alone is insufficient to meet the heating requirements.

[0053] In step S309, when the engine 3 is driven, the controller 21 drives the heat pump 15 so that its heat output is the difference between the heat required for heating and the heat released by the engine 3, since the heat required for heating is greater than the heat released by the engine 3. In other words, the heat pump 15 outputs the amount of heat that the engine 3 cannot release to meet the heat required for heating.

[0054] For example, as shown in Figure 7, when a request to start engine 3 is output at time t6, engine 3 starts, its rotational speed increases, and engine 3 outputs a heat output Pe. At this time, the heat pump 15 was driven by the heating request heat amount PN, but since engine 3 has started and output a heat output Pe, the heat output of the heat pump 15 decreases to the heat output Ph (=PN-Pe), which is the difference between the heating request heat amount PN and the heat output Pe of engine 3. Therefore, the total heating output remains unchanged at PN at time t6.

[0055] In step S311 of Figure 6B, the controller 21 determines whether the temperature of the engine 3's coolant is above the heat pump stop temperature. The heat pump stop temperature is a temperature lower than the engine stop temperature that stops the engine 3, and is a preset temperature for stopping the heat pump 15, for example, 80°C. If the temperature of the engine 3's coolant is above the heat pump stop temperature, the process proceeds to step S313; otherwise, it proceeds to step S325.

[0056] In step S313, the controller 21 stops the heat pump 15 if the cooling water temperature rises above the heat pump stop temperature after driving the heat pump 15 in step S307. For example, as shown in Figure 7, at time t7, if the cooling water temperature of the engine 3 rises above the heat pump stop temperature of 80°C due to an unexpected reduction in heating load, the heat pump 15 stops and the heat output becomes 0. Therefore, the total heating output is reduced to the heat output Pe of the engine 3. This makes it possible to prevent the cooling water temperature from rising to the engine stop temperature or switching temperature.

[0057] In step S315, the controller 21 determines whether the temperature of the engine 3's coolant is above the engine stop temperature. If the temperature of the engine 3's coolant is above the engine stop temperature, the process proceeds to step S317; otherwise, it returns to step S311.

[0058] In step S317, the controller 21 detects that the coolant temperature is above the engine stop temperature and stops the engine 3. This prevents the coolant temperature from reaching the switching temperature even if the coolant temperature continues to rise further after the heat pump 15 is stopped due to an unexpected reduction in heating load, etc. The controller 21 also stops the engine 3 if a request to stop the engine 3 is output based on energy management control.

[0059] In step S319, the controller 21 determines whether the heat pump 15 is stopped or not. If it is stopped, the process proceeds to step S321; otherwise, the process proceeds to step S323.

[0060] In step S321, the controller 21 starts the heat pump 15 in order to output the required amount of heat for heating, since the engine 3 stopped in step S317.

[0061] In step S323, the controller 21 drives the heat pump 15 so that its heat output equals the heating requirement. For example, as shown in Figure 7, at time t8, when the coolant temperature reaches the engine stop temperature of 85°C, the engine 3 stops, the engine speed becomes 0, and the heat output of the engine 3 also becomes 0. Then the heat pump 15 starts up and is driven with a heat output equal to the heating requirement PN. Therefore, the total heating output rises to the heating requirement PN even when the engine 3 is stopped.

[0062] In step S325, the controller 21 determines whether the power to the hybrid vehicle 1 is turned off. If the power is not turned off, the process returns to step S301. On the other hand, if the power is turned off, the heating control process for high heating loads according to this embodiment is terminated.

[0063] [Effects of the Embodiment] As described in detail above, in this embodiment, when the engine 3 is driven while the heat pump 15 is being driven to heat the cabin, the controller 21 stops the heat pump 15, and when the amount of heat released by the engine 3 causes the coolant temperature to rise above the engine stop temperature, which is lower than the switching temperature, the engine 3 is stopped. This prevents the coolant temperature from rising to the switching temperature, thus preventing the coolant from circulating to the radiator 45. Therefore, since the thermal energy of the coolant is prevented from being released from the radiator 45 during winter heating, heating efficiency can be improved and the fuel efficiency of the hybrid vehicle 1 can be improved.

[0064] Furthermore, in this embodiment, when the engine 3 is driven, if the required amount of heat for heating is greater than the amount of heat dissipated by the engine 3, the controller 21 drives the heat pump 15 so that its heat output is the difference between the required amount of heat for heating and the amount of heat dissipated by the engine 3. This allows the heat output of the heat pump 15 to compensate when the required amount of heat for heating is large and the amount of heat dissipated by the engine 3 alone is insufficient. Also, since only the insufficient amount of heat is compensated for by the heat output of the heat pump 15, heating efficiency can be improved and the fuel efficiency of the hybrid vehicle 1 can be improved.

[0065] Furthermore, in this embodiment, the controller 21 stops the heat pump 15 after it has been driven, if the temperature of the coolant rises to a heat pump stop temperature that is lower than the engine stop temperature. This prevents the coolant temperature from rising before it reaches the engine stop temperature.

[0066] Furthermore, in this embodiment, the controller 21 drives the heat pump 15 when the coolant temperature is lower than the minimum starting temperature when the hybrid vehicle 1 is started. When the coolant temperature rises above the minimum starting temperature, the controller 21 drives the engine 3 to raise the coolant temperature to the heating requirement temperature using the heat output of the heat pump 15 and the heat output of the engine 3. As a result, when the hybrid vehicle 1 is started, the coolant temperature can be efficiently raised to the heating requirement temperature by utilizing both the heat pump 15 and the engine 3.

[0067] As described above, embodiments of the present invention have been presented, but the statements and drawings that constitute part of this disclosure should not be understood as limiting the invention. Various alternative embodiments, examples, and operational techniques will become apparent to those skilled in the art from this disclosure. [Explanation of Symbols]

[0068] 1. Hybrid vehicle 3 Engines 5.9 Motor Generator 7, 11 Inverters 13 batteries 15 Heat pump 17 Cooling System 21 Controllers 23, 25 Motor Controller 27 Battery Controller 31 Compressor 33 Water-cooled condensers 35 Expansion valve 37 Outdoor heat exchanger 41 Thermostat 43. Air conditioning control unit 45 Radiator 47 Temperature Sensor 49 Heater core 51 Fans T-tire

Claims

1. A heating control method for a hybrid vehicle, which raises the temperature of the coolant by the heat output of an electric-driven heating device and the amount of heat emitted by an internal combustion engine to heat the interior of the vehicle, and circulates the coolant to an outdoor heat exchanger for cooling, When the heating system is being driven to heat the interior of the vehicle, if the internal combustion engine is driven, the heating system will be stopped. If the amount of heat dissipated by the internal combustion engine causes the temperature of the cooling water to rise above the internal combustion engine shutdown temperature, which is lower than the switching temperature at which the cooling water is circulated to the outdoor heat exchanger, the internal combustion engine will be shut down. A method for controlling the heating system in a hybrid vehicle.

2. When the internal combustion engine is driven, if the amount of heat required for heating the vehicle interior is greater than the amount of heat emitted by the internal combustion engine, the heating device is driven so that its heat output becomes equal to the difference between the amount of heat required for heating and the amount of heat emitted by the internal combustion engine. A heating control method for a hybrid vehicle according to claim 1.

3. If, after the heating system has been driven, the temperature of the cooling water rises to a heating system stop temperature that is lower than the internal combustion engine stop temperature, the heating system will be stopped. A heating control method for a hybrid vehicle according to claim 2.

4. When the hybrid vehicle is started, if the temperature of the coolant is lower than the minimum starting temperature required to start the internal combustion engine, the heating system is activated. When the temperature of the coolant rises above the minimum starting temperature, the internal combustion engine is driven, and the heat output of the heating system and the heat output of the internal combustion engine raise the temperature of the coolant to the required heating temperature for heating the vehicle interior. A heating control method for a hybrid vehicle according to any one of claims 1 to 3.

5. A heating control device for a hybrid vehicle that raises the temperature of the cooling water to heat the cabin by using the heat output of an electric-driven heating device and the amount of heat emitted by an internal combustion engine, and circulates the cooling water to an outdoor heat exchanger for cooling, When the heating system is being driven to heat the interior of the vehicle, if the internal combustion engine is driven, the heating system will be stopped. If the amount of heat dissipated by the internal combustion engine causes the temperature of the cooling water to rise above the internal combustion engine shutdown temperature, which is lower than the switching temperature at which the cooling water is circulated to the outdoor heat exchanger, the internal combustion engine will be shut down. A heating control system for hybrid vehicles.

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