Vehicle air conditioning system and vehicle air conditioning method
The vehicle air conditioning system includes: a refrigerant circuit; a heat medium circuit including high-temperature medium and low-temperature medium circuits; interior and exterior heat exchangers; an exhaust heat recovery circuit; and a switching part. The system operates in: a mode in which the heat medium in the high-temperature medium circuit is supplied to the interior heat exchanger and exhaust heat from onboard equipment is recovered by the heat medium in the low-temperature medium circuit, while the heat medium recovered and transferred exhaust heat to the refrigerant is supplied to the exterior heat exchanger; and another mode in which the heat medium in the high-temperature medium circuit is supplied to the interior heat exchanger and exhaust heat from onboard equipment is recovered by the heat medium in the low-temperature medium circuit, while the heat medium recovered and transferred exhaust heat to the refrigerant is caused to bypasses the exterior heat exchanger.
1 . A vehicle air conditioning system comprising:
a refrigerant circuit in which a refrigerant circulates in accordance with a refrigerating cycle;
a heat medium circuit that includes a high-temperature medium circuit in which a heat medium absorbing heat from the refrigerant of the refrigerant circuit circulates and a low-temperature medium circuit in which a heat medium releasing heat to the refrigerant of the refrigerant circuit circulates;
an interior heat exchanger that causes heat exchange between the heat medium and air;
an exterior heat exchanger that causes heat exchange between the heat medium and outside air;
an exhaust heat recovery circuit that is configured such that heat is transferrable and receivable between onboard equipment and the heat medium; and
a switch unit that is configured to switch a direction in which the heat medium flows,
wherein the switch unit is configured such that, in an exhaust heat recovery heating mode, in which the heat medium of the high-temperature medium circuit is supplied to the interior heat exchanger, exhaust heat from the onboard equipment is recovered to the heat medium of the low-temperature medium circuit, and the heat medium that has recovered the exhaust heat and that has released heat to the refrigerant is supplied to the exterior heat exchanger in a case where a first condition in which a temperature of the onboard equipment is lower than a heating target temperature set in the air conditioning system, and
wherein the switch unit is configured such that, in an exhaust-heat-as-main-heat-source heating mode, in which the heat medium of the high-temperature medium circuit is supplied to the interior heat exchanger, the exhaust heat from the onboard equipment is recovered to the heat medium of the low-temperature medium circuit, and the heat medium that has recovered the exhaust heat and that has released heat to the refrigerant is caused to bypass the exterior heat exchanger in a case where a second condition in which a temperature of the heat medium of the low-temperature medium circuit that has released heat to the refrigerant after recovering the exhaust heat from the onboard equipment is higher than a temperature of the outside air is satisfied in addition to the first condition, and
wherein the exhaust heat recovery heating mode and the exhaust-heat-as main-heat source heating mode are provided as operating modes of the air conditioning system, and
wherein the exhaust heat recovery circuit includes,
a heat exchange path in which the heat medium of one of the high-temperature medium circuit and the low-temperature medium circuit is thermally coupled to the onboard equipment,
a bypass of high-temperature side through which the heat medium of the high-temperature medium circuit bypasses the onboard equipment, and
a bypass of low-temperature side through which the heat medium of the low-temperature medium circuit bypasses the onboard equipment, and
the heat mediums are distributable to the heat exchange path and the bypasses by operating the switch unit.
2 . The vehicle air conditioning system according to claim 1 , further comprising:
an outside air temperature sensor that detects a temperature of the outside air,
a heat medium temperature sensor that detects a temperature of the heat medium at an outlet of an evaporator in which heat is released from the heat medium to the refrigerant, at an inlet of the exterior heat exchanger, or between the outlet and the inlet; and
a controller that controls operation of the switch unit in accordance with an operating mode,
wherein the controller selects the exhaust-heat-as-main-heat-source heating mode by using an outside air temperature detected by the outside air temperature sensor and a temperature detected by the heat medium temperature sensor.
3 . The vehicle air conditioning system according to claim 2 ,
wherein the interior heat exchanger includes a first heat exchanger and a second heat exchanger that are disposed in series in a direction in which the air is caused to flow by a blower, and
in the exhaust-heat-as-main-heat-source heating mode, the heat medium of the high-temperature medium circuit is supplied to the first heat exchanger on a windward side and the heat medium that has recovered the exhaust heat and has released heat to the refrigerant is supplied to the second heat exchanger on a leeward side.
4 . The vehicle air conditioning system according to claim 2 ,
wherein a high-temperature side exhaust heat recovery heating mode in which the exhaust heat from the onboard equipment is recovered to the heat medium of the high-temperature medium circuit, the heat medium that has recovered the exhaust heat and that has absorbed heat from the refrigerant is supplied to the interior heat exchanger, and the heat medium of the low-temperature medium circuit is supplied to the exterior heat exchanger is provided as the operating mode.
5 . The vehicle air conditioning system according to claim 1 ,
wherein the interior heat exchanger includes a first heat exchanger and a second heat exchanger that are disposed in series in a direction in which the air is caused to flow by a blower, and
in the exhaust-heat-as-main-heat-source heating mode, the heat medium of the high-temperature medium circuit is supplied to the first heat exchanger on a windward side and the heat medium that has recovered the exhaust heat and has released heat to the refrigerant is supplied to the second heat exchanger on a leeward side.
6 . The vehicle air conditioning system according to claim 5 , further comprising:
a damper that is configured to change an amount of inflow of the air that passes through the first heat exchanger and that flows into the second heat exchanger,
wherein, in the exhaust-heat-as-main-heat-source heating mode, the damper is operated to restrict the air from flowing into the second heat exchanger.
7 . The vehicle air conditioning system according to claim 6 ,
wherein a dehumidification and heating mode in which the heat medium of the low-temperature medium circuit is supplied to the first heat exchanger and the heat medium of the high-temperature medium circuit is supplied to the second heat exchanger is provided as an operating mode.
8 . The vehicle air conditioning system according to claim 6 ,
wherein a high-temperature side exhaust heat recovery heating mode in which the exhaust heat from the onboard equipment is recovered to the heat medium of the high-temperature medium circuit, the heat medium that has recovered the exhaust heat and that has absorbed heat from the refrigerant is supplied to the interior heat exchanger, and the heat medium of the low-temperature medium circuit is supplied to the exterior heat exchanger is provided as an the operating mode.
9 . The vehicle air conditioning system according to claim 5 ,
wherein a dehumidification and heating mode in which the heat medium of the low-temperature medium circuit is supplied to the first heat exchanger and the heat medium of the high-temperature medium circuit is supplied to the second heat exchanger is provided as an operating mode.
10 . The vehicle air conditioning system according to claim 9 ,
wherein a high-temperature side exhaust heat recovery heating mode in which the exhaust heat from the onboard equipment is recovered to the heat medium of the high-temperature medium circuit, the heat medium that has recovered the exhaust heat and that has absorbed heat from the refrigerant is supplied to the interior heat exchanger, and the heat medium of the low-temperature medium circuit is supplied to the exterior heat exchanger is provided as the operating mode.
11 . The vehicle air conditioning system according to claim 5 ,
wherein a high-temperature side exhaust heat recovery heating mode in which the exhaust heat from the onboard equipment is recovered to the heat medium of the high-temperature medium circuit, the heat medium that has recovered the exhaust heat and that has absorbed heat from the refrigerant is supplied to the interior heat exchanger, and the heat medium of the low-temperature medium circuit is supplied to the exterior heat exchanger is provided as an operating mode.
12 . The vehicle air conditioning system according to claim 1 ,
wherein a high-temperature side exhaust heat recovery heating mode in which the exhaust heat from the onboard equipment is recovered to the heat medium of the high-temperature medium circuit, the heat medium that has recovered the exhaust heat and that has absorbed heat from the refrigerant is supplied to the interior heat exchanger, and the heat medium of the low-temperature medium circuit is supplied to the exterior heat exchanger is provided as an operating mode.
13 . A vehicle air conditioning method in which a vehicle air conditioning system is used, the air conditioning system including a refrigerant circuit in which a refrigerant circulates in accordance with a refrigerating cycle, a heat medium circuit that includes a high-temperature medium circuit in which a heat medium absorbing heat from the refrigerant of the refrigerant circuit circulates and a low-temperature medium circuit in which a heat medium releasing heat to the refrigerant of the refrigerant circuit circulates, an interior heat exchanger that causes heat exchange between the heat medium and air, an exterior heat exchanger that causes heat exchange between the heat medium and outside air, an exhaust heat recovery circuit that is configured such that heat is transferrable and receivable between onboard equipment and the heat medium, and a switch unit that is configured to switch a direction in which the heat medium flows, the air conditioning method comprising:
causing the heat medium of the low-temperature medium circuit to recover exhaust heat from the onboard equipment in a case where a first condition in which a temperature of the onboard equipment is lower than a heating target temperature set in the air conditioning system, and
causing the heat medium of the low-temperature medium circuit to recover the exhaust heat from the onboard equipment and causing the heat medium that has recovered the exhaust heat to bypass the exterior heat exchanger in a case where a second condition in which a temperature of the heat medium of the low-temperature medium circuit that has released heat to the refrigerant after recovering the exhaust heat from the onboard equipment is higher than a temperature of the outside air is satisfied in addition to the first condition.
14 . A vehicle air conditioning system comprising:
a refrigerant circuit in which a refrigerant circulates in accordance with a refrigerating cycle;
a heat medium circuit that includes a high-temperature medium circuit in which a heat medium absorbing heat from the refrigerant of the refrigerant circuit circulates and a low-temperature medium circuit in which a heat medium releasing heat to the refrigerant of the refrigerant circuit circulates;
an interior heat exchanger that causes heat exchange between the heat medium and air;
an exterior heat exchanger that causes heat exchange between the heat medium and outside air,
an exhaust heat recovery circuit that is configured such that heat is transferrable and receivable between onboard equipment and the heat medium; and
a switch unit that is configured to switch a direction in which the heat medium flows,
wherein the switch unit is configured such that, in an exhaust heat recovery heating mode, in which the heat medium of the high-temperature medium circuit is supplied to the interior heat exchanger, exhaust heat from the onboard equipment is recovered to the heat medium of the low-temperature medium circuit, and the heat medium that has recovered the exhaust heat and that has released heat to the refrigerant is supplied to the exterior heat exchanger in a case where a first condition in which a temperature of the onboard equipment is lower than a heating target temperature set in the air conditioning system, and
wherein the switch unit is configured such that, in an exhaust-heat-as-main-heat-source heating mode, in which the heat medium of the high-temperature medium circuit is supplied to the interior heat exchanger, the exhaust heat from the onboard equipment is recovered to the heat medium of the low-temperature medium circuit, and the heat medium that has recovered the exhaust heat and that has released heat to the refrigerant is caused to bypass the exterior heat exchanger in a case where a second condition in which a temperature of the heat medium of the low-temperature medium circuit that has released heat to the refrigerant after recovering the exhaust heat from the onboard equipment is higher than a temperature of the outside air is satisfied in addition to the first condition, and
wherein the exhaust heat recovery heating mode and the exhaust-heat-as main-heat source heating mode are provided as operating modes of the air conditioning system, and
wherein a high-temperature side exhaust heat recovery heating mode in which the exhaust heat from the onboard equipment is recovered to the heat medium of the high-temperature medium circuit, the heat medium that has recovered the exhaust heat and that has absorbed heat from the refrigerant is supplied to the interior heat exchanger, and the heat medium of the low-temperature medium circuit is supplied to the exterior heat exchanger is provided as an operating mode.