METHOD AND APPARATUS FOR COOLING AN AIR CONDITIONING SYSTEM CONTROLLER

Abstract

An air conditioning system for use with a vehicle is configured to provide conditioned air. The air conditioning system includes a controller configured to vary a flow of the conditioned air and the controller is arranged to be cooled by the conditioned air.

Claims

1. An air conditioning system for use with a vehicle, the air conditioning system comprising an electric energy source configured to provide electric energy, an air conditioner including a compressor configured to be driven by the electric energy and an evaporator including a coil and a fan configured to conduct air across the coil to provide conditioned air during operation of the air conditioner, and a frequency drive connected with the electric energy source and the compressor, the frequency drive configured to direct the electric energy from the electric energy source to the compressor and to vary at least one of a frequency and a voltage of the electric energy to vary at least one of a speed and a torque of the compressor to meet a desired cooling load of the air conditioner, and wherein the frequency drive is positioned in a flow path of the conditioned air to cause the conditioned air to cool the frequency drive during use of the air conditioning system.

2. The air conditioning system of claim 1, wherein the frequency drive comprises a variable frequency drive.

3. The air conditioning system of claim 2, wherein the variable frequency drive is positioned downstream of the coil.

4. The air conditioning system of claim 2, wherein the variable frequency drive is positioned upstream of the coil.

5. The air conditioning system of claim 1, wherein the electric energy source includes at least one of a battery, capacitor, and a motor-generator.

6. The air conditioning system of claim 1, wherein the compressor of the air conditioner is driven directly by the electric energy.

7. The air conditioning system of claim 1, wherein the frequency drive includes a liquid-cooled frequency drive and the air conditioning system further includes a heat exchanger fluidly connected with the liquid-cooled frequency drive.

8. The air conditioning system of claim 7, wherein at least a portion of the heat exchanger is positioned in the flow path of the conditioned air.

9. The air conditioning system of claim 1, wherein the frequency drive includes a thermal portion that generates heat during use and the thermal portion is positioned in the flow path of the conditioned air.

10. An air conditioning system for use with a vehicle, the air conditioning system comprising an air conditioner configured to provide conditioned air during use of the air conditioner, the air conditioner including a compressor configured to be driven by electric energy, and a controller electrically connected with the compressor, the controller configured to vary at least one of a speed and a torque of the compressor, and at least a portion of the controller is positioned in a flow path of the conditioned air.

11. The air conditioning system of claim 10, wherein the controller comprises a variable frequency drive.

12. The air conditioning system of claim 11, wherein the air conditioner further includes an evaporator and the variable frequency drive is located in the flow path of the conditioned air downstream of the evaporator.

13. The air conditioning system of claim 12, further comprising a battery connected with the variable frequency drive and configured to direct the electric energy having a direct current to the variable frequency drive.

14. The air conditioning system of claim 10, wherein the controller comprises a liquid-cooled variable frequency drive electrically connected with the compressor and a heat exchanger that is fluidly connected with the liquid-cooled variable frequency drive and at least a portion of the heat exchanger is positioned in the flow path of the conditioned air.

15. A method comprising the steps of providing an air conditioner configured to provide conditioned air, the air conditioner including a compressor and an evaporator in fluid communication with the compressor, connecting a controller with the compressor, the controller configured to vary at least one of a speed and a torque of the compressor, and positioning a thermal portion of the controller in a flow path of the conditioned air.

16. The method of claim 15, further comprising driving the compressor with electric energy.

17. The method of claim 16, wherein the controller is configured to vary at least one of a frequency and a voltage of the electric energy to vary the at least one of the speed and the torque of the compressor.

18. The method of claim 16, wherein the thermal portion of the controller comprises a variable frequency drive.

19. The method of claim 15, wherein the controller comprises a liquid-cooled variable frequency drive and a heat exchanger in fluid communication with the liquid-cooled variable frequency drive and the thermal portion of the controller comprises at least a portion of the heat exchanger.

20. The method of claim 19, further comprising positioning the liquid-cooled variable frequency drive out of the flow path of the conditioned air.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 is a diagrammatic view of an air conditioning system in accordance with the present disclosure showing that the air conditioning system includes an air conditioner, a controller, and optionally an electric energy source such as, for example, a battery, capacitor, motor-generator, and any combination thereof and that the controller includes a variable frequency drive configured to be cooled by the conditioned air produced by the air conditioner;

[0020] FIG. 2 is a perspective and diagrammatic view of the air conditioning system of FIG. 1;

[0021] FIG. 3 is a diagrammatic view of an another embodiment of an air conditioning system in accordance with the present disclosure showing that the air conditioning system includes an air conditioner, a controller, and optionally an electric energy source and that the controller includes a liquid-cooled variable frequency drive and a heat exchanger fluidly coupled to the liquid-cooled variable frequency drive and the heat exchanger is configured to be cooled by conditioned air produced by the air conditioner during use of the air conditioner;

[0022] FIG. 4 is a perspective and diagrammatic view of the air conditioning system of FIG. 3; and

[0023] FIG. 5 is another diagrammatic view of the air conditioning system of FIG. 3.

DETAILED DESCRIPTION OF THE DRAWINGS

[0024] For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to a number of illustrative embodiments illustrated in the drawings and specific language will be used to describe the same.

[0025] A first embodiment of an air conditioning system 10 in accordance with the present disclosure is shown in FIGS. 1 and 2. The air conditioning system 10 includes a controller 14 comprising a frequency drive 16 and an air conditioner 12 connected with the variable frequency drive 16. The frequency drive 16 is located in a flow path of conditioned air 32 produced by the air conditioner 12 to cool the variable frequency drive 16 during use of the air conditioner 12. A second embodiment of an air conditioning system 210 in accordance with the present disclosure is shown in FIGS. 3-5. The air conditioning system 210 includes an air conditioner 212 and a controller 214. The controller 214 includes a liquid-cooled frequency drive 216 and a heat exchanger 234. The heat exchanger 234 is located in a flow path of conditioned air 32 produced by the air conditioner 212. In the illustrative embodiments, frequency drives 16, 216 comprise variable frequency drives.

[0026] The air conditioning system 10 is adapted for use in a vehicle (not shown) such as, for example, a bus. The air conditioning system 10 includes the air conditioner 12, the controller 14, and, optionally, an electric energy source 18 as shown in FIGS. 1 and 2. The air conditioner 12 is configured to provide conditioned air 32 for a passenger compartment of the vehicle. The conditioned air 32 may include air that has been cooled by an evaporator 22 of the air conditioner 12. The conditioned air 32 may include ambient air that is moved by a blower 28 toward the evaporator 22.

[0027] The controller 14 comprises the variable frequency drive 16 and the variable frequency drive 16 is configured to vary at least one of a frequency and a voltage of electric energy used to power the air conditioner 12. In embodiments that include the electric energy source, the electric energy source 18 is configured to provide the electric energy to the controller 14. The variable frequency drive 16 is located in the flow path of the conditioned air 32 to cause the conditioned air 32 to cool the variable frequency drive 16 during use of the air conditioning system 10.

[0028] The air conditioner 12 includes a compressor 20 and an evaporator 22 as shown in FIGS. 1 and 2. The compressor 20 is configured to be driven by the electric energy for example from electric energy source 18 to compress refrigerant (or other fluid). In the illustrative embodiment, the compressor 20 of the air conditioner 12 is driven directly by the electric energy. That is, the compressor 20 is an electrically powered compressor 20 and not powered by rotating energy, for example, from a motor.

[0029] When the refrigerant reaches the evaporator 22, the refrigerant absorbs heat from the surrounding atmospheric air and vaporizes to cool the air and produce the conditioned air 32 which is then blown out of the air conditioner 12 to cool the vehicle. Illustratively, the air conditioner 12 further includes a condenser 24 and an expansion tank 26 connected with the compressor 20 and the evaporator 22.

[0030] The illustrative evaporator 22 includes a coil 30 and a blower 28 as shown in FIGS. 1 and 2. The refrigerant is conducted through the coil 30 and the blower 28 directs a flow of air across the coil 30 to blow the conditioned air 32 out of the air conditioner 12.

[0031] The controller 14 is connected with the compressor 20 and configured to vary at least one of a frequency and a voltage of electric energy powering the compressor 20 to vary at least one of a speed and a torque of the compressor 20 to meet a desired cooling load of the air conditioning system 10. A thermal portion of the controller 14 produces heat during use of the controller 14. The thermal portion is located in a flow path of the conditioned air 32 so that that thermal portion of the controller 14 is cooled by the conditioned air 32 during use of the air conditioning system 10 as suggested in FIG. 1.

[0032] The frequency drive 16 may receive the desired cooling load from operator input. The frequency drive 16 drive may determine the desired cooling load.

[0033] In illustrative embodiments, the thermal portion of the controller 14 comprises one or more components and/or one or more portions of components of the controller 14. In illustrative embodiments, the thermal portion of the controller 14 is positioned downstream of the coil 30 of the evaporator 22 in a flow path of the conditioned air 32. In some embodiments, the thermal portion of the controller 14 is positioned upstream of the coil 30 of the evaporator 22 in a flow path of the blower 28.

[0034] Illustratively, the controller 14 comprises the variable frequency drive 16 and at least a portion of the variable frequency drive 16 comprises the thermal portion of the controller 14. As a result, at least a portion of the variable frequency drive 16 is located in the flow path of conditioned air 32.

[0035] The electric energy source 18 is configured to direct electric energy to the variable frequency drive 16 and/or to the compressor 20. Illustratively, the electric energy source 18 provides electric energy having a direct current. In illustrative embodiments, the electric energy source 18 comprises one or more of a battery, a capacitor, and a motor-generator. The battery and/or capacitor may be chemical, capacitive, or any other suitable alternative.

[0036] Illustratively, the air conditioning system 10 is incorporated into a vehicle. In some embodiments, the vehicle includes a powertrain and the air conditioning system 10. The powertrain includes a prime mover and wheels configured to be driven by the prime mover. In illustrative embodiments, the prime mover comprises a combustion engine. In other embodiments, the prime mover comprises an electric motor. The electric energy source 18 may be configured to be powered by energy produced by the prime mover. The electric energy source 18 may be further configured to start the prime mover.

[0037] The air conditioning system 210 is substantially similar to the air conditioning system 10 and includes the air conditioner 12, a controller 214, and, optionally, the electric energy source 18 as shown in FIGS. 3-5. The controller 214 includes the liquid-cooled variable frequency drive 216 and the heat exchanger 234 connected fluidly to the liquid-cooled variable frequency drive 216. The liquid-cooled variable frequency drive 216 is configured to vary at least one of the frequency and the voltage of electric energy used to power the air conditioner 12. At least a portion of the heat exchanger 234 is located in the flow path of the conditioned air 32 to cause the conditioned air 32 to cool the heat exchanger 234 during use of the air conditioning system 10. In some embodiments, the liquid-cooled variable frequency drive 216 is spaced apart from the flow path of the conditioned air such that the liquid-cooled variable frequency drive 216 is positioned out of the flow path of the conditioned air.

[0038] During use of the air conditioning system 210, a liquid is conducted through the heat exchanger 234 and the liquid-cooled variable frequency drive 216. The liquid is conducted through the liquid-cooled variable frequency drive 216 to remove heat from the liquid-cooled variable frequency drive 216. The warmed liquid is conducted through the heat exchanger 234 and the conditioned air 32 is conducted across the heat exchanger 234 to remove heat from and cool the liquid. The liquid may then be conducted to the liquid-cooled variable frequency drive 216 to cool the liquid-cooled variable frequency drive 216.

[0039] In some embodiments, the liquid is conducted directly from the heat exchanger 234 to the liquid-cooled variable frequency drive 216. In other embodiments, the liquid is conducted from the heat exchanger 234 to other components of the air conditioning system 210 before being directed to the liquid-cooled variable frequency drive 216. In some embodiments, the liquid continuously cools the liquid-cooled variable frequency drive 216. In some embodiments, the controller 214 further includes a valve that can be varied to adjust the flow of the liquid through the heat exchanger 234 and the liquid-cooled variable frequency drive 216.

[0040] In some embodiments, the frequency drive includes a fluid-cooled variable frequency drive. In some embodiments, the fluid used to cool the fluid-cooled variable frequency drive is a gas. In some embodiments, the heat exchanger 234 is located in a flow path of the blower 28 downstream of the evaporator 22. In some embodiments, the heat exchanger 234 is located in a flow path of the blower 28 upstream of the evaporator 22.

[0041] While the disclosure has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments thereof have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.