U.S. patent application number 13/602417 was filed with the patent office on 2014-03-06 for mild ambient vehicular heat pump system.
This patent application is currently assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC. The applicant listed for this patent is Harry E. Eustice, Mark D. Nemesh, Bryan M. Styles, Mukund S. Wankhede. Invention is credited to Harry E. Eustice, Mark D. Nemesh, Bryan M. Styles, Mukund S. Wankhede.
Application Number | 20140060102 13/602417 |
Document ID | / |
Family ID | 50098681 |
Filed Date | 2014-03-06 |
United States Patent
Application |
20140060102 |
Kind Code |
A1 |
Nemesh; Mark D. ; et
al. |
March 6, 2014 |
MILD AMBIENT VEHICULAR HEAT PUMP SYSTEM
Abstract
A vehicular heat pump system for controlling the temperature of
a passenger compartment and vehicle battery is provided. The heat
pump system may include a cooling mode and a heating mode. The
components of each of the respective heating and cooling circuits
may include: a compressor, an AC condenser, a heat pump condenser,
a cabin evaporator, a heat pump evaporator, a receiver/dryer, a
plurality of expansion devices, and a plurality of flow control
valves. The use of multiple evaporators and condensers eliminates
the need to reverse the direction of refrigerant flow upon a change
in operating mode; therefore, the position of the low-pressure side
of the system remains constant in all operating modes. The
low-pressure side of the system is not cooled with ambient air,
minimizing the complexity of the system and eliminating the need to
interrupt heating mode in order to de-ice the outside heat
exchanger.
Inventors: |
Nemesh; Mark D.; (Troy,
MI) ; Wankhede; Mukund S.; (Fort Gratiot, MI)
; Styles; Bryan M.; (South Lyon, MI) ; Eustice;
Harry E.; (Troy, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Nemesh; Mark D.
Wankhede; Mukund S.
Styles; Bryan M.
Eustice; Harry E. |
Troy
Fort Gratiot
South Lyon
Troy |
MI
MI
MI
MI |
US
US
US
US |
|
|
Assignee: |
GM GLOBAL TECHNOLOGY OPERATIONS
LLC
Detroit
MI
|
Family ID: |
50098681 |
Appl. No.: |
13/602417 |
Filed: |
September 4, 2012 |
Current U.S.
Class: |
62/238.7 ;
62/238.1 |
Current CPC
Class: |
B60H 1/00278 20130101;
B60H 1/00921 20130101; B60H 2001/00307 20130101; B60H 2001/00949
20130101 |
Class at
Publication: |
62/238.7 ;
62/238.1 |
International
Class: |
F25B 30/02 20060101
F25B030/02; F25B 29/00 20060101 F25B029/00 |
Claims
1. A heat pump system for use in a vehicle having a battery and a
passenger compartment comprising: a heating circuit, having a
low-pressure side and a high-pressure side, the heating circuit
configured to circulate refrigerant in a first operating mode, to
heat the passenger compartment and cool the battery; a cooling
circuit, having a low pressure side and a high pressure side, the
cooling circuit configured to circulate refrigerant in a second
operating mode, to cool and dehumidify the passenger compartment
and cool the battery; wherein in the low pressure side of each of
the respective heating circuit and cooling circuit remains constant
during operation of the heat pump system in each of the respective
first operating mode and second operating mode.
2. The heat pump system of claim 1 wherein the heating circuit
further includes: a compressor configured to compress the
refrigerant; at least one low-side pressure sensor configured to
monitor the pressure of the refrigerant entering the compressor; at
least one high-side pressure sensor configured to monitor the
pressure of the refrigerant exiting the compressor; a first flow
control valve configured to receive refrigerant from the
compressor; a refrigerant-to-air heat pump condenser configured to
receive refrigerant from the first flow control valve and further
configured to cool and condense the refrigerant; and wherein the
refrigerant-to-air heat pump condenser is configured to exchange
heat between the refrigerant flowing through the refrigerant-to-air
heat pump condenser and air flowing across the refrigerant-to-air
heat pump condenser to heat the passenger compartment.
3. The heat pump system of claim 2 further comprising: a receiver
dryer configured to receive refrigerant from the refrigerant-to-air
heat pump condenser and further configured to remove moisture from
the refrigerant; a first expansion device configured to receive
refrigerant from the receiver dryer and further configured to allow
the refrigerant to cool and expand; a second flow control valve
configured to receive refrigerant from the receiver dryer; and
wherein the receiver dryer is configured to expel refrigerant to
one of the first expansion device and second flow control
valve.
4. The heat pump system of claim 3 wherein the receiver dryer is
configured to expel refrigerant to the first expansion device.
5. The heat pump system of claim 4 further comprising an RESS
chiller configured to act as a heat pump evaporator capable of
exchanging heat from air surrounding the vehicle battery to the
refrigerant, the RESS chiller further configured to receive
refrigerant from the first expansion device and expel refrigerant
to the compressor.
6. The heat pump system of claim 3 wherein the receiver dryer is
configured to expel refrigerant to the second flow control
valve.
7. The heat pump system of claim 6 further comprising: a second
expansion device configured to receive refrigerant from the second
flow control valve and further configured to allow the refrigerant
to cool and expand; and a cabin evaporator configured to receive
refrigerant from the second expansion device and expel refrigerant
to the compressor, the cabin evaporator further configured to
exchange heat between the refrigerant and air in the passenger
compartment to cool and dehumidify the passenger compartment.
8. The heat pump system of claim 1 wherein the cooling circuit
further comprises: a compressor configured to compress the
refrigerant; at least one low-side pressure sensor configured to
monitor the pressure of the refrigerant entering the compressor; at
least one high-side pressure sensor configured to monitor the
pressure of the refrigerant exiting the compressor; and an AC
condenser configured to receive refrigerant from one of the third
flow control valve and the compressor, the AC condenser further
configured to cool and condense the refrigerant.
9. The heat pump system of claim 8 wherein the AC condenser is
configured to receive refrigerant from the compressor and expel
refrigerant to the third flow control valve.
10. The heat pump system of claim 8 further comprising: a receiver
dryer configured to remove moisture from the refrigerant; and
wherein the AC condenser is configured to receive refrigerant from
the third flow control valve and expel refrigerant to the receiver
dryer.
11. The heat pump system of claim 8 further comprising: a receiver
dryer configured to receive refrigerant from one of the AC
condenser and the third flow control valve, the receiver dryer
further configured to remove moisture from the refrigerant; a first
thermal expansion device configured to receive refrigerant from the
receiver dryer and further configured to allow the refrigerant to
cool and expand; and an RESS chiller configured to act as a heat
pump evaporator capable of exchanging heat from air surrounding the
battery to the refrigerant, the RESS chiller further configured to
receive refrigerant from the first expansion device and expel
refrigerant to the compressor.
12. The heat pump system of claim 8 further comprising: a receiver
dryer configured to receive refrigerant from one of the AC
condenser and the third flow control valve, the receiver dryer
further configured to remove moisture from the refrigerant; a
second flow control valve configured to receive refrigerant from
the receiver dryer; a second expansion device configured to receive
refrigerant from the second flow control valve and further
configured to allow the refrigerant to cool and expand; a cabin
evaporator configured to receive refrigerant from the second
expansion device and expel refrigerant to the compressor, the cabin
evaporator further configured to exchange heat between the
refrigerant and air in the passenger compartment to cool and
dehumidify the passenger compartment.
13. The heat pump system of claim 1 wherein the heating circuit
includes: an compressor configured to compress the refrigerant; at
least one low-side pressure sensor configured to monitor the
pressure of the refrigerant entering the compressor; at least one
high-side pressure sensor configured to monitor the pressure of the
refrigerant exiting the compressor; a first flow control valve
configured to receive refrigerant from the compressor; a
refrigerant-to-coolant heat pump condenser having a refrigerant
cavity and a coolant cavity, the refrigerant-to-coolant heat pump
condenser configured to receive refrigerant from the first flow
control valve and further configured to exchange heat from
refrigerant flowing through the refrigerant cavity to coolant
flowing through the coolant cavity; a coolant heater core
configured to receive coolant from the refrigerant-to-coolant heat
pump condenser and further configured to exchange heat between the
coolant flowing through the coolant heater core and air flowing
across the coolant heater core to the passenger compartment; a
receiver dryer configured to receive refrigerant from the
refrigerant cavity, the receiver dryer further configured to remove
moisture from the refrigerant; a coolant valve configured to
receive coolant from the coolant heater core; a heating source
configured to receive coolant from the coolant valve and further
configured to warm the coolant; an electric coolant pump configured
to receive coolant from one of the coolant valve and heating source
and further configured to expel coolant to the coolant cavity; and
wherein the coolant valve is configured to direct coolant to one of
the heating source and the electric coolant pump.
14. The heat pump of claim 13 wherein the heat pump system further
includes: a first thermal expansion device configured to receive
refrigerant from the receiver dryer and further configured to allow
the refrigerant to cool and expand; and an RESS chiller configured
to act as a heat pump evaporator capable of exchanging heat from
air surrounding the vehicle battery to the refrigerant, the RESS
chiller further configured to receive refrigerant from the first
expansion device and expel refrigerant to the compressor.
15. The heat pump system of claim 13 further comprising: a second
flow control valve configured receive refrigerant from the receiver
dryer; a second expansion device configured to receive refrigerant
from the second flow control valve and further configured to allow
the refrigerant to cool and expand; and a cabin evaporator
configured to receive refrigerant from the second expansion device
and expel refrigerant to the compressor, the cabin evaporator
further configured to exchange heat between the refrigerant and air
in the passenger compartment to cool and dehumidify the passenger
compartment.
16. A vehicle comprising: a passenger compartment; a vehicle
battery configured to provide a power source for the vehicle; a
heat pump system including: a heating circuit, having a
low-pressure side and a high-pressure side, the heating circuit
configured to circulate refrigerant in a first operating mode, to
heat the passenger compartment and cool the battery; a cooling
circuit, having a low-pressure side and a high-pressure side, the
cooling circuit configured to circulate refrigerant in a second
operating mode, to cool and dehumidify the passenger compartment
and cool the battery; a plurality of flow control valves, including
at least a first flow control valve, a second flow control valve,
and a third flow control valve, each of the respective first,
second, and third flow control valves configured to receive and
selectively distribute refrigerant through one of the heating
circuit and cooling circuit; and wherein the low-pressure side of
each of the respective heating circuit and cooling circuit remains
constant during operation of the heat pump system in each of the
respective first operating mode and second operating mode.
17. The vehicle of claim 16 wherein the heating circuit includes: a
compressor configured to compress the refrigerant; at least one
low-side pressure sensor configured to monitor the pressure of the
refrigerant entering the compressor; at least one high-side
pressure sensor configured to monitor the pressure of the
refrigerant exiting the compressor; the first flow control valve
configured to receive refrigerant from the compressor; a
refrigerant-to-air heat pump condenser configured to receive
refrigerant from the first flow control valve and further
configured to condense and cool the refrigerant, wherein the
refrigerant-to-air heat pump condenser is configured to exchange
heat between the refrigerant flowing through the refrigerant-to-air
heat pump condenser and air flowing across the refrigerant-to-air
heat pump condenser to heat the passenger compartment; a receiver
dryer configured to receive refrigerant from the heat pump
condenser and further configured to remove moisture from the
refrigerant; a first expansion device configured to receive
refrigerant from the receiver dryer and further configured to allow
the refrigerant to cool and expand; and an RESS chiller configured
to act as a heat pump evaporator capable of exchanging heat from
air surrounding the vehicle battery to the refrigerant, the RESS
chiller further configured to receive refrigerant from the first
expansion device and expel refrigerant to the compressor.
18. The vehicle of claim 17 wherein the heating circuit further
includes: a compressor configured to compress the refrigerant; at
least one low-side pressure sensor configured to monitor the
pressure of the refrigerant entering the compressor; at least one
high-side pressure sensor configured to monitor the pressure of the
refrigerant exiting the compressor; the first flow control valve
configured to receive refrigerant from the compressor; a
refrigerant-to-air heat pump condenser configured to receive
refrigerant from the first flow control valve and further
configured to condense and cool the refrigerant, wherein the
refrigerant-to-air heat pump condenser is configured to exchange
heat between the refrigerant flowing through the refrigerant-to-air
heat pump condenser and air flowing across the refrigerant-to-air
heat pump condenser to heat the passenger compartment; a receiver
dryer configured to receive refrigerant from the heat pump
condenser and further configured to remove moisture from the
refrigerant; the second flow control valve configured to receive
refrigerant from the receiver dryer; a second expansion device
configured to receive refrigerant from the second flow control
valve and further configured to allow the refrigerant to cool and
expand; and a cabin evaporator configured to receive refrigerant
from the second expansion device and expel refrigerant to the
compressor, the cabin evaporator further configured to exchange
heat between the refrigerant and air in the passenger compartment
to cool and dehumidify the passenger compartment.
19. The vehicle of claim 16 wherein the cooling circuit includes:
an compressor configured to compress the refrigerant; at least one
low-side pressure sensor configured to monitor the pressure of the
refrigerant entering the compressor; at least one high-side
pressure sensor configured to monitor the pressure of the
refrigerant exiting the compressor; an AC condenser configured to
receive refrigerant from one of the second flow control valve and
the compressor, the AC condenser further configured to cool and
condense the refrigerant; the third flow control valve configured
to receive refrigerant from one of the compressor and the AC
condenser; a receiver dryer configured to receive refrigerant from
one of the AC condenser and the third flow control valve, the
receiver dryer further configured to remove moisture from the
refrigerant; a first expansion device configured to receive
refrigerant from the receiver dryer and further configured to allow
the refrigerant to cool and expand; and an RESS chiller configured
to act as a heat pump evaporator capable of exchanging heat from
air surrounding the vehicle battery to the refrigerant, the RESS
chiller further configured to receive refrigerant from the first
expansion device and expel refrigerant to the compressor.
20. The vehicle of claim 16 wherein the cooling circuit further
includes: a compressor configured to compress the refrigerant; at
least one low-side pressure sensor configured to monitor the
pressure of the refrigerant entering the compressor; at least one
high-side pressure sensor configured to monitor the pressure of the
refrigerant exiting the compressor; an AC condenser configured to
receive refrigerant from one of the second flow control valve and
the compressor, the AC condenser further configured to cool and
condense the refrigerant; the third flow control valve configured
to receive refrigerant from one of the compressor and the AC
condenser; a receiver dryer configured to receive refrigerant from
one of the AC condenser and the third flow control valve, the
receiver dryer further configured to remove moisture from the
refrigerant; the second flow control valve configured to receive
refrigerant from the receiver dryer; a second expansion device
configured to receive refrigerant from the second flow control
valve and further configured to allow the refrigerant to cool and
expand; and a cabin evaporator configured to receive refrigerant
from the second expansion device and expel refrigerant to the
compressor, the cabin evaporator further configured to exchange
heat between the refrigerant and air in the passenger compartment
to cool and dehumidify the passenger compartment.
Description
TECHNICAL FIELD
[0001] The disclosure relates to a vehicular heat pump system for
use in mild ambient temperatures.
BACKGROUND
[0002] In conventional heating, ventilating, and air conditioning
(HVAC) systems, two separate fluid circuits are present: a
refrigerant fluid circuit for cooling the cabin and a coolant fluid
circuit for heating the cabin. The cooling circuit circulates a
refrigerant which may be a compound such as R-134a or the like. The
heating circuit circulates a fluid which may generally be a mixture
of ethylene glycol and water. Such HVAC systems may include
reversible refrigerant heat pump systems, in which the refrigerant
flow is controlled by refrigerant valves, thus, permitting the heat
pump system to operate in both cabin heating mode and cabin cooling
mode, by reversing the function of the two heat exchangers.
[0003] In cabin cooling mode, refrigerant flows from the compressor
through an outside heat exchanger acting as a condenser, into an
expansion valve, and through an inside heat exchanger acting as an
evaporator. Heat is extracted from the air blown across the inside
heat exchanger (evaporator), thereby providing cooled air to the
passenger compartment.
[0004] In cabin heating mode, the refrigerant heat exchanger
located outside the passenger compartment (outside heat exchanger)
acts as an evaporator. The refrigerant heat exchanger inside the
passenger compartment (inside heat exchanger) acts as a condenser.
The refrigerant flows from the compressor through the inside heat
exchanger acting as a condenser, into a receiver and orifice tube
or other type of expansion device, and through the outside heat
exchanger acting as an evaporator. Heat from the refrigerant is
absorbed by the air flowing across the inside heat exchanger, which
is blown into the passenger compartment to provide heat.
SUMMARY
[0005] A vehicular heat pump system for controlling the temperature
of the passenger compartment and vehicle battery, for use in mild
ambient temperatures, is provided. The heat pump system may include
two operating modes: a cooling mode and a heating mode, which, in
operation, may circulate a refrigerant. The refrigerant is
generally directed along a heating circuit in heating mode and a
cooling circuit in cooling mode. The refrigerant may be directed
along one of the respective heating circuit or cooling circuit and
through a plurality of components to cool or warm the passenger
compartment and to cool the vehicle battery.
[0006] The vehicular heat pump system may include a compressor, an
AC condenser, a heat pump condenser, a cabin evaporator, a
rechargeable energy storage system (RESS) chiller acting as heat
pump evaporator, a receiver dryer, a plurality of expansion
devices, and a plurality of flow control valves.
[0007] The vehicular heat pump system may operate in two operating
modes, namely heating mode and cooling mode, either independently
or simultaneously. During heating mode, the system employs a heat
pump condenser, inside the HVAC module or within the vehicle
underhood, and the RESS chiller as the heat pump evaporator.
Additionally, the heating circuit may include a cabin evaporator,
which may be configured to cool and dehumidify air transmitted to
the passenger compartment. In cooling mode, the system utilizes an
independent AC condenser outside the HVAC module, and a cabin
evaporator.
[0008] It is, therefore, not necessary to require the reversal of
refrigerant flow when changing operating modes. Absent the
requirement to reverse the system, the position of the low-pressure
side of the system, defined between one of the plurality of
expansion devices and the compressor, remains constant in all
operating modes reducing or eliminating the need to de-ice an
outside heat exchanger in heating mode, and allowing uninterrupted
heating of the passenger compartment.
[0009] The above features and advantages, and other features and
advantages, of the present invention are readily apparent from the
following detailed description of some of the best modes and other
embodiments for carrying out the invention, as defined in the
appended claims, when taken in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1A is a schematic diagram of a first configuration of a
first embodiment of the vehicular heat pump system operating in
heating mode;
[0011] FIG. 1B is a schematic diagram of a second configuration of
the first embodiment of the vehicular heat pump system operating in
heating mode;
[0012] FIG. 2A is a schematic diagram of a third configuration of
the first embodiment of the vehicular heat pump system operating in
cooling mode;
[0013] FIG. 2B is a schematic diagram of a fourth configuration of
the first embodiment of the vehicular heat pump system operating in
cooling mode;
[0014] FIG. 3 is a schematic diagram of a fifth configuration of
the first embodiment of the vehicular heat pump system; and
[0015] FIG. 4 is a schematic diagram of a second embodiment of the
vehicular heat pump system wherein the heat pump condenser is a
refrigerant-to-coolant heat exchanger located in the vehicle
underhood.
DETAILED DESCRIPTION
[0016] The following description and figures refer to example
embodiments and are merely illustrative in nature and not intended
to limit the invention, its application, or uses. Throughout the
figures, some components are illustrated with standardized or basic
symbols. These symbols are representative and illustrative only,
and are in no way limiting to any specific configuration shown, to
combinations between the different configurations shown, or to the
claims. All descriptions of componentry are open-ended and any
examples of components are non-exhaustive.
[0017] Referring to the figures, wherein like reference numbers
correspond to like or similar components throughout the several
views, a vehicular heat pump system 100, 200 for controlling the
temperature of a vehicle passenger compartment 122 and vehicle
battery 115, for use in cool and mild ambient temperatures is
provided and shown in a variety of configurations and operating
modes, in FIGS. 1A-B, 2A-B, 3, and 4.
[0018] The heat pump system 100, may operate in two modes: a
cooling mode, as shown in FIGS. 2A-B, 3, and 4, and a heating mode,
as shown in FIGS. 1A-B, 3, and 4. When operating in each of the
respective heating mode and cooling mode, the heat pump system 100
circulates a refrigerant. The refrigerant may be one of R-134a,
R-1234yf, R-744, R-152a or the like. In heating mode, the
refrigerant may be directed through a plurality of components along
the heating circuit 125 to heat and dehumidify a vehicle passenger
compartment 122 and/or cool a vehicle battery 115. In cooling mode
the refrigerant may be directed through a plurality of components
along the cooling circuit 124 to cool and dehumidify the vehicle
passenger compartment 122 and/or cool the vehicle battery 115.
[0019] The heating circuit 125, shown generally in FIG. 1A, may
include a compressor 102 having a compressor inlet 126 and a
compressor outlet 127; at least one high-side refrigerant pressure
sensor 117; a first flow control valve 114; a second flow control
valve 106; a third flow control valve 104; a heat pump condenser
111a; a receiver dryer 105; a first expansion device 108; a second
expansion device 107; an RESS chiller 110 functioning as a heat
pump evaporator; a cabin evaporator 113; at least one low-side
refrigerant pressure sensor 116; and at least one control module
123.
[0020] The heating circuit 125 has a distinct high-pressure side
and low-pressure side. The high-pressure side, wherein the
refrigerant is in a condensed high pressure state, is defined
between a compressor outlet 127 and each of the respective
expansion devices 107, 108. The low-pressure side of the system,
wherein the refrigerant in an expanded, low pressure state, is
defined between each of the respective expansion devices 107, 108
and the compressor inlet 126.
[0021] The compressor 102 may be driven by an electric motor (not
shown), which may be of the single or variable speed variety. The
compressor 102 may also be a pump driven by a belt connected to the
engine crankshaft (not shown). The compressor 102 may include a
compressor inlet 126 and a compressor outlet 127. The compressor
102 may be configured to receive refrigerant gas on the
low-pressure side of the system at the compressor inlet 126 and may
pressurize the refrigerant gas into a high-pressure state. The
compressor 102 may be further configured to expel compressed
refrigerant gas to the compressor outlet 127, exiting on the
high-pressure side of the system.
[0022] The at least one low-side refrigerant pressure sensor 116
may be positioned on the low-pressure side of the compressor 102
proximate the compressor inlet 126. The at least one high-side
refrigerant pressure sensor 117 may be positioned on the
high-pressure side of the compressor 102 proximate the compressor
outlet 127.
[0023] The heating circuit 125 may additionally include a first
flow control valve 114 that may be fully open when the heat pump
system 100 is operating in heating mode. The first flow control
valve 114 may be fully open in heating mode and may be configured
to direct and selectively distribute refrigerant to the heat pump
condenser 111a. The third flow control valve 104 may be fully
closed in heating mode. The second flow control valve 106 may be
fully open, in heating mode, if passenger compartment 122
dehumidification is needed; the second flow control valve 106 may
be fully closed, in heating mode, if passenger compartment 122
dehumidification is not needed.
[0024] The heat pump condenser may be a refrigerant-to-air heat
exchanger 111a located within the HVAC module 121, as shown in
FIGS. 1A-B. Alternatively, the heat pump condenser may be a
refrigerant-to-coolant heat exchanger 111c located in the vehicle
underhood 152, as shown in FIG. 4. The heat pump condenser 111a,
111c may include a condenser inlet 128 and a condenser outlet 129.
The heat pump condenser 111a, 111c may be configured to receive
pressurized refrigerant gas at the condenser inlet 128, and may
extract heat from the pressurized refrigerant gas as it passes
through the condenser 111a, 111c, to the extent that the
pressurized refrigerant gas is cooled to a point at which it is
reclaimed into a liquid state. The heat extracted from the
refrigerant may be exchanged to the air flowing across the heat
pump condenser 111a. The heated air may be directed to the
passenger compartment 122. The cooled liquid refrigerant may be
expelled from the heat pump condenser 111a, 111c at the heat pump
condenser outlet 129.
[0025] The receiver dryer 105 may include a receiver dryer inlet
134 and a receiver dryer outlet 135. The receiver dryer 105 may
further include a plurality of desiccants (not shown) to attract
and remove moisture from the system 100. The receiver dryer 105 may
receive the high-pressure refrigerant liquid at the receiver dryer
inlet 134 and expel the high pressure refrigerant liquid from the
receiver dryer outlet 135.
[0026] The first expansion device 108 may allow the high pressure
liquid refrigerant to expand, reducing the pressure in the system
100. The first expansion device 108 may direct and selectively
distribute refrigerant to the RESS chiller 110, at a significantly
reduced pressure. The first expansion device 108 may be a
thermostatic or thermal expansion valve, and may be configured to
hold a constant evaporator superheat state as the refrigerant
enters RESS chiller 110, which acts as a heat pump evaporator. The
thermostatic or thermal expansion valve may be a conventional,
mechanically driven, thermal expansion valve, with which no
electronic devices are associated, as shown in FIGS. 1A-B, or the
thermal expansion valve may be an electronically driven thermal
expansion valve, as shown in FIGS. 2A-B, 3, and 4. The first
expansion device 108 may be either electronic or mechanical in any
of the configurations shown in FIGS. 1A-B, 2A-B, 3, and 4. The
first expansion device 108 may monitor, such as with a sensor or a
bulb, the temperature of the refrigerant leaving the RESS chiller
110, and may improve the performance of the heat exchange by
letting additional or less refrigerant into the RESS chiller
110.
[0027] The RESS chiller 110 may be located outside the HVAC module
121. The RESS chiller 110 may function as a heat pump evaporator
that may include coils (not shown) or the like to dissipate heat
from the battery 115 to the cooled refrigerant. The RESS chiller
110 may direct refrigerant over the low-side pressure sensor 116
and back to the compressor 102.
[0028] If dehumidification of the passenger compartment 122 is
needed, the heating circuit 125 may also circulate refrigerant
along flow path 150, as shown in FIG. 1A. In such a case, the
heating circuit 125 may also include a cabin evaporator 113, a
second flow control valve 106, and a second expansion device 107.
Additionally, the second flow control valve 106 may be fully open,
during heating mode, when passenger compartment 122
dehumidification is desired. The second expansion device 107 may be
configured to receive refrigerant from the receiver dryer 105
through the second flow control valve 106 and may be further
configured to allow the high-pressure refrigerant to expand,
reducing the pressure in the system 100.
[0029] The second expansion device 107 may control and selectively
distribute refrigerant to the cabin evaporator 113, at a
significantly reduced pressure. The second expansion device 107 may
be a thermostatic or thermal expansion valve, and is configured to
hold a constant evaporator superheat state as the refrigerant
enters the cabin evaporator 113. The thermostatic or thermal
expansion valve may be a conventional, mechanically driven, thermal
expansion valve, with which no electronic devices are associated,
as shown in FIGS. 2A-B, or the thermal expansion valve may be an
electronically driven thermal expansion valve, as shown in FIGS.
1A-B, 3, and 4. The second expansion device 107 may be either
electronic or mechanical in any of the configurations shown in
FIGS. 1A-B, 2A-B, 3, and 4. The second expansion device 107 may
monitor, such as with a sensor or a bulb, the temperature of the
refrigerant leaving the cabin evaporator 113, and may improve the
performance of the heat exchange by letting additional or less
refrigerant into the cabin evaporator 113.
[0030] The cabin evaporator 113 may be located within the HVAC
module 121. The cabin evaporator 113 may include coils (not shown).
The cabin evaporator 113 may be configured to cool and dehumidify
the air flowing across the coils (not shown) and into the passenger
compartment 122. The cabin evaporator 113 may further include a fan
(not shown) to direct air over the coils impregnated with
refrigerant, and facilitate the direction of the air into the
passenger compartment 122. The cabin evaporator 113 may be further
configured to direct refrigerant over the low-side pressure sensor
116 and back to the compressor 102.
[0031] The cooling circuit 124, shown generally in FIG. 2A-B may
include a compressor 102 having a compressor inlet 126 and a
compressor outlet 127; at least one high-side refrigerant pressure
sensor 117; an AC condenser 103; a first flow control valve 114; a
second flow control valve 106, a third flow control valve 104; a
receiver dryer 105; a first expansion device 108; an RESS chiller
110 functioning as a heat pump evaporator; a second expansion
device 107; a cabin evaporator 113; at least one low-side
refrigerant pressure sensor 116; and at least one control module
123.
[0032] The cooling circuit 124 has a distinct high pressure side
and low pressure side. The high pressure side, wherein the
refrigerant is in a condensed high pressure state, is defined
between a compressor outlet 127 and each of the respective
expansion devices 107, 108. The low pressure side of the system,
wherein the refrigerant in an expanded low pressure state, is
defined between each of the respective expansion devices 107, 108
and the compressor inlet 126.
[0033] The compressor 102 may be driven by an electric motor (not
shown), which may be of the single or variable speed variety. The
compressor 102 may also be a pump driven by a belt connected to the
engine crankshaft (not shown). The compressor 102 may include a
compressor inlet 126 and a compressor outlet 127. The compressor
102 may receive refrigerant gas on the low pressure side of the
system at the compressor inlet 126 and may pressurize the
refrigerant gas into a high pressure state. The compressor 102 may
direct compressed refrigerant gas to the compressor outlet 127,
exiting on the high pressure side of the system 100.
[0034] The at least one low-side refrigerant pressure sensor 116
may be positioned on the low-pressure side of the compressor 102
proximate the compressor inlet 126. The at least one high-side
refrigerant pressure sensor 117 may be positioned on the
high-pressure side of the compressor 102 proximate the compressor
outlet 127.
[0035] In cooling mode, the first flow control valve 114 may be
fully closed. Each of the respective second flow control valve 106
and third flow control valve 104 may be fully open, in cooling mode
and may be further configured to receive and expel refrigerant.
[0036] The AC condenser 103 may be located outside the HVAC module
121. The AC condenser 103 may include an AC condenser inlet 130 and
an AC condenser outlet 131. The AC condenser 103 may receive
pressurized refrigerant gas at the condenser inlet 130, and may
cool and condense the pressurized refrigerant gas as it flows
through the AC condenser 103, to the extent that the pressurized
refrigerant gas is cooled and condensed to a point at which it is
reclaimed into a liquid state. The AC condenser outlet 131 may be
configured to expel cooled liquid refrigerant.
[0037] The receiver dryer 105 may include a receiver dryer inlet
134 and a receiver dryer outlet 135. The receiver dryer 105 may
further include a plurality of desiccants (not shown) to attract
and remove moisture from the system 100. The receiver dryer 105 may
receive the high-pressure refrigerant liquid at the receiver dryer
inlet 134 and expel the high pressure refrigerant liquid from the
receiver dryer outlet 135 to one of the first expansion device 108
and the second expansion device 107.
[0038] The first and second expansion devices 108, 107 may allow
the high pressure liquid refrigerant to expand, reducing the
pressure of the refrigerant as it exits the first and second
expansion devices 108, 107. The first and second expansion devices
108, 107 may be further configured to control and selectively
distribute refrigerant to each of the respective RESS chiller 110
functioning as a heat pump evaporator and cabin evaporator 113, at
a significantly reduced pressure. The first and second expansion
devices 108, 107 may be thermostatic or thermal expansion valves,
and may be configured to hold a constant evaporator superheat state
as the refrigerant enters one of the RESS chiller 110, which acts
as a heat pump evaporator and the cabin evaporator 113. Each of the
respective first expansion device 108 and second expansion device
107 may be either electronic or mechanical in any of the
configurations shown in FIGS. 1A-B, 2A-B, 3, and 4. The first and
second expansion devices 108, 107 may monitor, such as with a
sensor or a bulb, the temperature of the refrigerant leaving either
the RESS chiller 110 or cabin evaporator 113, and may improve the
performance of the heat exchange by letting additional or less
refrigerant into the RESS chiller 110 or cabin evaporator 113.
[0039] The RESS chiller 110 may include coils (not shown) or the
like to dissipate heat from the battery 115 to the cooled
refrigerant. The RESS chiller 110 may direct refrigerant over the
low-side pressure sensor 116 and back to the compressor 102.
[0040] The cabin evaporator 113 may be located within the HVAC
module 121. The cabin evaporator 113 may include coils (not shown),
which may function to allow the refrigerant flow across the coils
(not shown). The cabin evaporator 113 may be configured to cool and
dehumidify the air flowing across the coils (not shown) and into
the passenger compartment 122. The cabin evaporator 113 may further
include a fan (not shown) to direct air over the coils impregnated
with refrigerant, and facilitate the direction of the air into the
passenger compartment 122. The cabin evaporator 113 may be
configured to direct refrigerant over the low-side pressure sensor
116 and back to the compressor 102.
[0041] As shown in FIGS. 1A-B, 2A-B, 3, and 4, each of the
respective heating circuit 125 and cooling circuit 124 may include
at least one control module 123 that may be electrically connected
with at least one electrical connection 136 and may be configured
to monitor and control the heat pump system 100 in a variety of
operating modes. The at least one control module 123 may be
configured to communicate with the motor (not shown) which may
drive the compressor 102. The at least one control module 123 may
further be configured to communicate with the first and second
expansion devices 108, 107; the plurality of flow control valves
104, 106, 114, 120; the pressure sensors 116, 117; and other
subsystems through the at least one electrical connection 136.
[0042] Illustrative examples of the vehicular heat pump system 100,
200 are shown in FIGS. 1A-B, 2A-B, 3, and 4. Each of the
embodiments depicts a vehicular heat pump system 100, 200 capable
of operating in both heating mode and cooling mode without the need
to reverse the system 100, 200 upon a change in operating mode.
Additionally, each embodiment will allow a hybrid or electric
vehicle to operate in both hybrid mode and electric vehicle mode
(EV mode) in ambient temperatures at least as low as about
4.degree. C.
[0043] FIGS. 1A-B depict a first configuration and a second
configuration of a first embodiment of the heat pump system 100
operating in heating mode. In the first configuration, shown in
FIG. 1A, low-pressure refrigerant gas is directed across a low-side
pressure sensor 116 to a compressor 102. The compressor 102 may be
configured to receive the low-pressure refrigerant gas at the
compressor inlet 126. The compressor 102 may compress the
refrigerant gas, produce a high-pressure refrigerant gas, and expel
the high pressure refrigerant gas at the compressor outlet 127.
[0044] The high pressure refrigerant gas may be expelled from the
compressor outlet 127 and directed across a high-side pressure
sensor 117, to the first flow control valve 114. The first flow
control valve 114 may be fully open in heating mode, and may be
configured to direct and selectively distribute the high pressure
refrigerant gas to the heat pump condenser 111a.
[0045] The heat pump condenser 111a, may be a refrigerant-to-air
heat exchanger and may be housed within the HVAC module 121. The
heat pump condenser 111a may be configured to receive the
high-pressure refrigerant gas from the first flow control valve 114
at the heat pump condenser inlet 128. The heat pump condenser 111a
may, additionally, be configured to cool and condense the
pressurized refrigerant gas as it flows through the heat pump
condenser 111a, to the extent that the refrigerant reclaims liquid
form. The heat extracted from the refrigerant may be exchanged to
the air flowing across the heat pump condenser 111a. The heated air
may be directed to the passenger compartment 122. The cooled liquid
refrigerant may be expelled from the heat pump condenser outlet 129
and directed to the receiver dryer 105.
[0046] The receiver dryer 105 may be configured to receive the
liquid refrigerant at the receiver dryer inlet 134 from the heat
pump condenser 111a. The receiver dryer 105 may be further
configured to remove moisture from the system 100 through the use
of a plurality of desiccants (not shown), which may attract and
remove additional moisture from the refrigerant being directed to
one of the cabin evaporator 113 and the RESS chiller 110 acting as
a heat pump evaporator. After the excess moisture is extracted from
the system 100, the refrigerant liquid may be expelled from the
receiver dryer outlet 135 and directed to at least one of the first
expansion device 108 or second expansion device 107.
[0047] If cabin dehumidification is not needed, the second flow
control valve 106 may be fully closed and all refrigerant expelled
from the receiver dryer 105 may be directed to the first expansion
device 108. If cabin dehumidification is needed, the second flow
control valve 106 may be fully open and the refrigerant expelled
from the receiver dryer 105 may be directed and selectively
distributed to one of the first expansion device 108 and the second
expansion device 107.
[0048] High pressure, liquid refrigerant may be directed from the
receiver dryer 105 to the first expansion device 108. The first
expansion device 108 may be configured to receive refrigerant and
further configured to allow the liquid refrigerant to depressurize
and expand. The first expansion device 108 may be further
configured to direct and selectively distribute refrigerant to the
RESS chiller 110, which may act as a heat pump evaporator.
[0049] The RESS chiller 110 acting as a heat pump evaporator may be
configured to receive the cooled liquid refrigerant from the first
expansion device 108. The RESS chiller 110 may be further
configured to dissipate excess heat from the battery 115 to the
refrigerant, and expel the refrigerant over the at least one
low-side pressure sensor 116 and back to compressor 102.
[0050] High pressure, liquid refrigerant may also be directed from
the receiver dryer 105 to the second expansion device 107.
Refrigerant directed to the second expansion device 107 may flow
along flow path 150 and may first pass through the second flow
control valve 106, which may be fully open, when cabin
dehumidification is needed. The second flow control valve 106 may
be configured to direct and selectively distribute refrigerant to
the second expansion device 107. The second expansion device 107
may be configured to receive the liquid refrigerant and allow the
liquid refrigerant to depressurize and expand. The second expansion
device 107 may be further configured to direct and selectively
distribute refrigerant to the cabin evaporator 113.
[0051] The cabin evaporator 113 may be configured to receive the
cooled liquid refrigerant from the second expansion device 107. The
cabin evaporator 113 may be further configured to cool and
dehumidify the air flowing across the cabin evaporator 113 and into
the passenger compartment 122. The cabin evaporator 113 may be
further configured to expel the refrigerant over the low-side
pressure sensor 116 and back to the compressor 102.
[0052] In the second configuration, shown in FIG. 1B, the third
flow control valve 104 may be relocated and placed between the
compressor 102 and the AC condenser 103, to combat refrigerant
pooling inside the AC condenser 103.
[0053] FIGS. 2A-B depict a third configuration and a fourth
configuration of the first embodiment of the heat pump system 100
operating in cooling mode. In the third configuration of the first
embodiment, shown in FIG. 2A, the compressor 102 may be configured
to receive low pressure refrigerant gas at the compressor inlet
126, after the low pressure refrigerant gas passes a low-side
pressure sensor 116. The compressor 102 may compress the
refrigerant gas, producing a high-pressure refrigerant gas. The
compressor 102 may be further configured to expel the high-pressure
refrigerant gas at the compressor outlet 127.
[0054] The high-pressure refrigerant gas may be directed from the
compressor outlet 127 across a high-side pressure sensor 117 and
directed to an AC condenser 103. The AC condenser 103 may be
configured to receive the high-pressure refrigerant gas at an AC
condenser inlet 130. The AC condenser 103 may additionally be
configured to cool and condense the high-pressure refrigerant gas,
to the extent that the refrigerant reclaims liquid form. The cooled
liquid refrigerant may be expelled from the AC condenser outlet 131
and directed to the third flow control valve 104. The third flow
control valve 104 may be configured to direct and selectively
distribute the high-pressure refrigerant gas to the receiver dryer
105.
[0055] The receiver dryer 105 may be configured to receive the
liquid refrigerant at the receiver dryer inlet 134. The receiver
dryer 105 may be further configured to remove moisture from the
system through the use of a plurality of desiccants (not shown),
which may attract and remove moisture prior to the refrigerant
being directed to one of the cabin evaporator 113 and RESS chiller
110. After the excess moisture is extracted from the system, the
refrigerant liquid may be expelled from the receiver dryer outlet
135 and directed and selectively distributed to one of the second
flow control valve 106 and the first expansion device 108. The
selective direction by the at least one control module 123 may be
based on the necessary balance between the cooling of the passenger
compartment 122 and the cooling of the battery 115.
[0056] If cooling is desired in the passenger compartment 122 only,
all refrigerant will be directed to the second flow control valve
106, which will be fully open, and on to second expansion device
107. If cooling is desired for the battery 115 only, all
refrigerant will be directed to the first expansion device 108, as
the second flow control valve 106 will be fully closed. If both the
passenger compartment 122 and the battery 115 require cooling, the
refrigerant will be directed and selectively distributed to each of
the respective first expansion device 108 and the second expansion
device 107.
[0057] High-pressure, liquid refrigerant directed to the second
expansion device 107 may first pass through the second flow control
valve 106, which may be fully open in cooling mode. The second flow
control valve 106 may be configured to direct, selectively
distribute, and meter refrigerant to the second expansion device
107. The second expansion device 107 may be configured to receive
the liquid refrigerant and allow the liquid refrigerant to
depressurize and expand. The second expansion device 107 may direct
and selectively distribute refrigerant to the cabin evaporator
113.
[0058] The cabin evaporator 113 may be configured to receive the
cooled liquid refrigerant from the second expansion device 107. The
cabin evaporator 113 may be further configured to cool and
dehumidify the air flowing across the cabin evaporator 113 and into
the passenger compartment 122. The cabin evaporator 113 may be
further configured to expel and direct the refrigerant over the
low-side pressure sensor 116 and back to the compressor 102.
[0059] If battery 115 cooling is needed in addition to passenger
compartment 122 cooling, high-pressure liquid refrigerant may also
be directed from the receiver dryer 105 to the first expansion
device 108 in cooling mode. The first expansion device 108 may be
configured to receive the liquid refrigerant from the receiver
dryer 105 and allow the liquid refrigerant to depressurize and
expand. The first expansion device 108 may be further configured to
direct and selectively distribute refrigerant to the RESS chiller
110.
[0060] The RESS chiller 110 may act as a heat pump evaporator. The
RESS chiller 110 may be configured to receive the cooled liquid
refrigerant from the first expansion device 108. The RESS chiller
110 may be further configured to dissipate excess heat from the
battery 115 to the refrigerant, and expel and direct the
refrigerant over the low-side pressure sensor 116 and back to the
compressor 102.
[0061] In the fourth configuration of the first embodiment, shown
in FIG. 2B, the third flow control valve 104 may be relocated
between the compressor 102 and the AC condenser 103, to combat
refrigerant pooling inside the AC condenser 103. In the fourth
configuration, the third flow control valve 104 may be configured
to receive high-pressure refrigerant gas from the compressor outlet
127. The third flow control valve 104 may be fully open and may be
further configured to direct, selectively distribute, and meter
refrigerant flow to the AC condenser 103.
[0062] FIG. 3 depicts the fifth configuration of the first example
embodiment of the vehicular heat pump system 100, which is
applicable in both heating mode and cooling mode. In fifth
configuration, shown in FIG. 3, the first flow control valve 114
and the third flow control valve 104 may be replaced with a
three-way, two-position flow control valve 120. This three-way,
two-position control valve 120 can serve as the flow control valve
114 between the compressor 102 and heat pump condenser 111a, which
may be fully open in heating mode and the flow control valve 104
between the compressor 102 and AC condenser 103, which may be fully
open in cooling mode.
[0063] FIG. 4 depicts a second embodiment of the vehicular heat
pump system 200, which is applicable in both heating mode and
cooling mode. In the second embodiment, the cooling circuit 124
functions in the same manner as the cooling circuits 124 described
with respect to the third and fourth configurations of the first
embodiment shown in FIGS. 2A-2B and 3.
[0064] The heating circuit 125 of the second embodiment may contain
substantially the same structure as described with respect to the
first embodiment described above. However, the heat pump condenser
111c may be a refrigerant-to-coolant heat exchanger rather than a
refrigerant-to-air heat exchanger 111a. Further, in the third
example embodiment, the refrigerant-to-coolant heat pump condenser
111c may be located in the vehicle underhood 152, rather than
within the HVAC module 121.
[0065] The refrigerant-to-coolant heat pump condenser 111c may
include a refrigerant cavity 140 and a coolant cavity 137. The
refrigerant cavity 140 may include a refrigerant inlet 146 and a
refrigerant outlet 148. The coolant cavity 137 may include a
coolant inlet 138 and a coolant outlet 139.
[0066] The refrigerant-to-coolant heat pump condenser 111c may be
configured to receive pressurized refrigerant gas at the
refrigerant inlet 146, and may extract heat from the pressurized
gas as it flows through the refrigerant cavity 140 to the extent
that the pressurized refrigerant gas is cooled and condensed to a
point at which it is reclaimed into a liquid state. The heat
extracted from the refrigerant as it flows through the refrigerant
cavity 140 may be transferred to the coolant flowing through the
coolant cavity 137.
[0067] The warmed coolant flowing through the coolant cavity 137
may be expelled from the coolant outlet 139 and directed through a
coolant heater core 112. The coolant heater core 112 may be housed
in the HVAC module 121. Heat may then be transferred from the
coolant flowing through the coolant heater core 112 to the air
flowing across the coolant heater core 112. The heated air may be
directed across the coolant heater core 112 to the passenger
compartment 122.
[0068] In vehicles that are electric only propulsion vehicles, the
vehicular heat pump system 200 may further include: an electric
coolant pump 144. In such systems, coolant may be expelled from the
coolant heater core 112 and directed to the electric coolant pump
144. The electric coolant pump 144 may be configured to receive
coolant from the coolant heater core 112 and expel coolant to the
coolant cavity 137. The coolant cavity 137 may be configured to
receive coolant from the electric coolant pump 144 at the coolant
cavity inlet 138.
[0069] In advanced propulsion vehicles, the vehicular heat pump
system 200 may further include an electric coolant pump 144; a
heating source 143, such as an internal combustion engine, a fuel
cell stack, a fuel operated heater, a thermal storage device or the
like; and a coolant valve 142. In such systems, coolant may be
expelled from the coolant heater core 112 and directed to the
coolant valve 142. The coolant valve 142 may be a three-way,
two-position valve and may be configured to direct coolant flow
from the heater core 112 to the coolant pump 144, when the heating
source 143 is too cold to operate. When the heating source 143 is
sufficiently warmed, the coolant valve 142 may be further
configured to direct coolant flow from the coolant heater core 112
to the heating source 143, which may expel coolant to the coolant
pump 144.
[0070] The cooled, liquid refrigerant may be expelled from the heat
pump condenser outlet 148 and directed to the receiver dryer 105.
The receiver dryer 105 may be configured to receive the liquid
refrigerant at the receiver dryer inlet 134. The receiver dryer 105
may be further configured to remove moisture from the system
through the use of a plurality of desiccants (not shown), which may
attract and remove additional moisture from the refrigerant. After
the excess moisture is extracted from the system 100, the
refrigerant liquid may be expelled from the receiver dryer outlet
135 and directed to at least one of the respective first expansion
device 108 or the second expansion device 107.
[0071] If cabin dehumidification is not needed, all refrigerant
expelled from the receiver dryer 105 may be directed to the first
expansion device 108, as the second flow control valve 106 will be
fully closed. If cabin dehumidification is needed, the refrigerant
expelled from the receiver dryer 105 may be directed and
selectively distributed to one of the first expansion device 108
and the second expansion device 107, through the fully open second
control valve 106.
[0072] High pressure, liquid refrigerant directed to the second
expansion device 107, may flow along flow path 150 and may first
pass through the second flow control valve 106. The second flow
control valve 106, may be fully open in heating mode if passenger
compartment 122 dehumidification is needed. The second flow control
valve 106 may be configured to direct and selectively distribute
refrigerant to the second expansion device 107. The second
expansion device 107 may be configured to receive the liquid
refrigerant and allow the liquid refrigerant to depressurize and
expand. The second expansion device 107 may be further configured
to direct and selectively distribute refrigerant to the cabin
evaporator 113.
[0073] The cabin evaporator 113 may be configured to receive the
cooled, liquid refrigerant from the second expansion device 107.
The cabin evaporator 113 may be further configured to cool and
dehumidify the air flowing across the evaporator 113 and into the
passenger compartment 122. The cabin evaporator 113 may be further
configured to expel and direct refrigerant over the low-side
pressure sensor 116 and back to the compressor 102.
[0074] Refrigerant may also be directed from the receiver dryer 105
to the first expansion device 108. The first expansion device 108
may be configured to receive and allow the liquid refrigerant to
depressurize and expand. The first expansion device may be further
configured to direct and selectively distribute refrigerant to the
RESS chiller 110.
[0075] The RESS chiller 110 may act as a heat pump evaporator and
may be configured to receive the cooled, liquid refrigerant from
the first expansion device 108. The RESS chiller 110 may be further
configured to dissipate excess heat from the battery 115 to the
refrigerant, and expel and direct the refrigerant over the low-side
pressure sensor 116 and back to the compressor 102.
[0076] The mild ambient heat pump system 100 maintains an
independent heating circuit 125 and an independent cooling circuit
124. Therefore, the system 100 does not require a reversing upon a
change to the operating mode. Each of the heat exchangers always
function as an evaporator 110, 113 or always functions as a
condenser 103, 111a, 111c, rather than as conventional heat
exchangers, which switch between evaporator function and condenser
function upon a change in operating mode. Accordingly, the position
of the low-pressure side of the system remains constant in all
operating modes. The low-pressure side of the system is always
defined between each of the respective expansion devices 107, 108
and the compressor inlet 126. Additionally, the low-pressure side
of the heat pump system is not directly cooled with ambient air.
Such a configuration of the vehicular heat pump system 100, 200
allows for passenger compartment 122 heating in EV mode in mild and
cold ambient temperatures without interruption, as the de-icing of
the RESS chiller 110 during heating mode is not necessary. Such a
system 100, 200 also preserves underhood 152 packing space which
can be scarce in hybrid or electric vehicle models.
[0077] The detailed description and the drawings or figures are
supportive and descriptive of the invention, but the scope of the
invention is defined solely by the claims. While some of the best
modes and other embodiments for carrying out the claimed invention
have been described in detail, various alternative designs and
embodiments exist for practicing the invention defined in the
appended claims.
* * * * *