A COOLING SYSTEM AND METHOD FOR A MAGNETIC RESONANCE IMAGING SYSTEM

Abstract

 According to the invention, a cooling system (200) for an imaging system comprises a compressor module (210) that comprises a liquid cooler (204), a cooling circuit (220) coupled between an inlet and an outlet of the liquid cooler and configured to provide a circulation path for circulating liquid coolant of the liquid cooler between the inlet (206) and the outlet (208). The cooling circuit comprises a liquid cooled section (250) and an air cooled section (260), the liquid coolant flowing in the liquid cooled section is liquid cooled, and the liquid coolant flowing in the air cooled section is air cooled. The cooling system further comprises a controller (240) coupled to the cooling circuit and configured to detect a failure of liquid cooling and to determine the liquid cooling and/or the air cooling to operate either in an operation mode or an idle mode upon detecting the failure of liquid cooling. By providing a redundant or backup air cooling to dissipate heat of the liquid coolant flowing through the compressor module, the reliability of the cooling system is enhanced. In a preferred embodiment the imaging system is a magnetic resonance imaging system.

Description

FIELD OF THE INVENTION

[0001] This invention relates to the field of medical systems, and in particular to a cooling system for a magnetic resonance imaging (MRI) system.

BACKGROUND OF THE INVENTION

[0002] MRI systems use liquid helium to cool the superconducting magnetic coils. Heat is removed from the liquid helium via the use of a cooling system comprising a coldhead - compressor combination. Typically, the coldhead extends into the cryostat cooling the liquid helium of the magnet. The cooling system also employs helium as a refrigerant which is separate from liquid helium of the magnet. The refrigerant gas is compressed by the compressor, and the coldhead serves as an expansion engine for removing heat. Conventionally, the cooling system includes a water circulation system, e.g., a water chiller, that is coupled to the compressor to provide liquid cooling for dissipating the heat generated by the compression of the helium gas.

[0003] The cooling system is commonly operated continuously ("24/7") to prevent the vaporization and subsequent loss of liquid helium. When the cooling system fails, the expensive liquid helium begins to be lost, and, if the cooling system is not quickly repaired, magnet imaging function will be lost. Therefore, typically, expensive urgent repair service is required.

[0004] It is infeasible to provide redundant coldhead-compressor cooling systems due to size and efficiency constraints. A second coldhead would need to be situated in the cryostat reservoir, and would introduce a substantial amount of ambient heat (loss of cooling) into the reservoir when this second coldhead-compressor cooling system is in 'backup' (non-operating) mode.

[0005] Compounding this problem, advances in technology continue to be developed to reduce the size of the reservoir, thereby reducing the amount of expensive liquid helium required. With a small reservoir, however, the vaporization of a relatively small amount of liquid helium could force a shutdown of the MRI system. Accordingly, the reduction in size of the reservoir causes an increased dependence upon the reliability of the refrigeration system to minimize vaporization of the liquid helium. US20190003743A1 provides a cooling system with dual compressors. However, the cooling system with dual compressors has a higher cost and larger footprint area.

SUMMARY OF THE INVENTION

[0006] It is an object of the invention to provide a cost-efficient and compact cooling system that enables continuous operation of the cooling system.

[0007] According to the invention, this object is addressed by the subject matter of the independent claims. Various embodiments of the invention are described in the sub claims.

[0008] Therefore, according to the invention, a cooling system for a magnetic resonance imaging system comprises a compressor module that comprises a liquid cooler, a cooling circuit coupled between an inlet and an outlet of the liquid cooler and configured to provide a circulation path for circulating liquid coolant of the liquid cooler between the inlet and the outlet. The cooling circuit comprises a liquid cooled section and an air cooled section, the liquid coolant flowing in the liquid cooled section is liquid cooled, and the liquid coolant flowing in the air cooled section is air cooled. The cooling system further comprises a controller coupled to the cooling circuit and configured to detect a failure of the liquid cooling and to determine the liquid cooling and the air cooling to operate either in an operation mode or an idle mode upon detecting the failure of the liquid cooling. By providing a redundant or backup air cooling to dissipate heat of the liquid coolant flowing through the compressor module, the reliability of the cooling system is enhanced.

[0009] According to an embodiment of the present invention, the liquid cooled section is coupled in parallel with the air cooled section. The liquid cooled section comprises a first line extending from an outlet of a coolant module to an upstream inlet of a first check valve, the first check valve, a second line extending from a downstream outlet of the first check valve to the inlet of the liquid cooler, and a third line extending from the outlet of the liquid cooler to an inlet of the coolant module, and wherein the air cooled section comprises a second check valve, an air cooled heat exchanger with a fan, and a pump connected in series between the inlet and the outlet of the liquid cooler. By connecting the air cooled section in parallel with the liquid cooled section, the air cooling and liquid cooling can operate independently of each other. No matter what failure occurs to the liquid cooling, the air cooling can operate independently to provide continuous cooling to the liquid coolant flowing through the liquid cooler of the compressor module.

[0010] According to another embodiment of the present invention, the coolant system further comprises a refrigeration module configured to convert a working medium in liquid-phase into gas-phase by heat from the compressor module and compress the working medium in the gas-phase up to a higher pressure and a higher temperature, and a condensing module coupled to the refrigeration module to liquefying the high-pressure and high-temperature working medium in the gas-phase. Such two-stage cooling of evaporation and condensation provides a compacter structure of heat transfer.

[0011] According to yet another embodiment of the present invention, the first and second check valves passively control a flow direction of the liquid coolant in the cooling circuit based on the determined mode of operation of the liquid cooling and the air cooling. In a passive control, the first check valve and the second check valve which are referred to as one-way flow valves, are mechanically placed in the "open" state, without external power or influence, due to produced flow of liquid coolant.

[0012] According to yet another embodiment of the present invention, the cooling system further comprises a cabinet having a housing defined by a base wall, opposite side walls extending upwardly from side edges of the base wall and a top wall connected to upper ends of the side walls, wherein the housing of the cabinet is configured to define an interior of the cabinet, wherein a front access opening which defines an access to the interior of the cabinet is configured to be closed by a door panel attached to at least one of the side walls; and a separating wall extending between the top wall and the base wall and spaced apart from the side walls and configured to divide the interior of the cabinet into a first chamber and a second chamber, and wherein the air cooled section is positioned in the first chamber and the remaining components of the cooling system is positioned in the second chamber. Advantageously, components of the cooling system can be resided in a single cabinet and therefore the footprint area of the cooling system is significantly reduced.

[0013] According to another embodiment of the present invention, a part of the door panel covering the first chamber has a plurality of openings and configured to serve as an air exhaust side of the air cooling.

[0014] According to another embodiment of the present invention, the cabinet does not have a rear wall and the rear of the cabinet is configured to serve as an air intake side of the air cooling.

[0015] According to another embodiment of the present invention, the compressor module is configured to be wheeled into the interior of the cabinet.

[0016] According to another embodiment of the present invention, wherein the cooling circuit comprises an air cooled heat exchanger with a fan, a line coupled between an outlet of a coolant module and the air cooled heat exchanger, and a line coupled between the air cooled heat exchanger and the inlet of the liquid cooler, providing a combination of liquid cooling and air cooling that are coupled in series. Although the cooling system will encounter a failure in case of a flow blockage, it is still attractive owning to its low cost and compact structure.

[0017] According to the invention, a method of cooling a magnetic resonance imaging system comprises the steps of providing a liquid coolant from an outlet of a coolant module, directing the liquid coolant from the outlet of the coolant module to an inlet of a liquid cooler of a compressor module through a cooling circuit with a combination of liquid cooling and air cooling, dissipating heat generated by the compressor module by the liquid cooler to the liquid coolant, directing the heated liquid coolant from an outlet of the liquid cooler to an inlet of the coolant module, detecting a failure of the liquid cooling, and determining the liquid cooling and the air cooling to operate either in an operation mode or an idle mode upon detecting the failure of the liquid cooling.

[0018] According to some embodiment of the invention, the method may further comprise passively controlling a flow direction of the liquid coolant in the cooling circuit based on the determined mode of operation of the liquid cooling and the air cooling by a first and second check valves respectively positioned in the liquid cooling and air cooling.

[0019] According to yet another embodiment of the invention, the method may further comprise arranging the compressor module, the cooling circuit, and the coolant module in an interior of a cabinet, and dividing the interior of the cabinet into a first chamber and a second chamber by a separating wall.

[0020] Further, according to the invention, an MRI system comprising a cooling system according to any of the embodiments stated above is provided.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. Such an embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention.

FIG. 1 illustrates an MRI system 100 that includes a conventional cooling system;

FIG. 2 illustrates a cooling system 200 for an MRI system according to one embodiment of the present invention;

FIG. 3 illustrates a cooling system 300 for an MRI system according to another embodiment of the present invention;

FIG. 4A illustrates a schematic diagram of a next generation liquid cooling cabinet 400 according to one embodiment of the present invention;

FIG. 4B depicts a front view illustration of the next generation liquid cooling cabinet 400 according to one embodiment of the presentation invention;

FIG. 5 illustrates a cooling system 500 for an MRI according to yet another embodiment of the present invention; and

FIG. 6 illustrates a method for cooling an MRI according to one embodiment of the present invention.

[0022] Throughout the drawings, the same reference numerals indicate similar or corresponding features or functions. The drawings are included for illustrative purposes and are not intended to limit the scope of the invention.

DETAILED DESCRIPTION

[0023] In the following description, for purposes of explanation rather than limitation, specific details are set forth such as the particular architecture, interfaces, techniques, etc., in order to provide a thorough understanding of the concepts of the invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments, which depart from these specific details. In like manner, the text of this description is directed to the example embodiments as illustrated in the Figures, and is not intended to limit the claimed invention beyond the limits expressly included in the claims. For purposes of simplicity and clarity, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

[0024] FIG. 1 illustrates an example of an MRI system 100 that includes a conventional cooling system. The MRI system 100 includes a conventional water-cooled compressor unit 120. The water-cooled compressor module 120 includes a compressor 122 which supplies compressed helium gas to a coldhead 104 through manifold 112 and receives expanded helium gas from coldhead 104 through manifold 114. As illustrated in FIG. 1, the internal components of the MRI equipment 110, and in particular the superconducting magnetic coils (not illustrated), are cooled by liquid helium in a reservoir 102. The coldhead 104 is in thermal contact with the reservoir 102. In this manner, heat from the superconducting magnetic coils is transferred to the reservoir 102 of liquid helium, which is cooled by the coldhead 104. For the purposes of this disclosure, a "reservoir" is herein defined as a volume that contains liquid helium cooled by the coldhead 104. The water-cooled compressor module 120 further includes a water cooler 124 through which high pressure helium and/or high pressure oil from the compressor 122 flows. Cooling water flows through the water cooler 124 in a counter-flow heat transfer relation with the helium and oil. A water circulation module 140, e.g., a water chiller, provides cold water through a first line 104 and receives hot water through a second line 106, thereby dissipating heat generated by the compressor 122.

[0025] FIG. 2 illustrates an example of a cooling system 200 according to one embodiment of the present invention. The cooling system 200 includes a compressor module 210, a cooling circuit 220, a coolant module 230 and a controller 240. The compressor module 210 further comprises a compressor 202 and a liquid cooler 204. Low temperature coolant flows from an outlet 232 of the coolant module 230, through a line 222 to an upstream inlet of a first check valve 224. The first check valve 224 allows the low temperature coolant to flow in line 226 from a downstream outlet of the first check valve 224 and then to an inlet 206 of the liquid cooler 204. Heated by the heat generated by the compressor 202, high temperature coolant is outputted to an outlet 208 of the liquid cooler 204, and then flows to an inlet 234 of the coolant module 230 through line 228. The high temperature coolant is liquid cooled by the coolant module 230 and then is outputted as low temperature coolant to the outlet 232, thereby providing a continuous supply of coolant in a cooling system. It shall be acknowledged by the skilled in the art that the liquid coolant can be, but not limited to, water with an additive such as glycol.

[0026] To further enhance the reliability of the closed loop cooling system, the cooling circuit 200 further includes a second check valve 242, an air cooled heat exchanger 244 and a pump 246 is coupled in series between the inlet 206 and outlet 208 of the liquid cooler 204. More specifically, the pump 246 is connected to the line 228 to transfer the high temperature coolant from the outlet 208 of the liquid cooler 204 to finned-tube bundle of the air cooled heat exchanger 244. Fan 248 drives air through the finned-tube bundle of the air cooled heat exchanger 244 in a counter-flow heat transfer relation with the liquid coolant in the air cooled heat exchanger 244. Low temperature coolant is output from the air cooled heat exchanger 244 and flows to the inlet 206 of the liquid cooler 204 through the second check valve 242, whose upstream inlet is connected to the output of the air cooled heat exchanger 244 and downstream outlet is connected to the line 226 on the downstream side of the first check valve 224. In a passive control, the first check valve 224 and the second check valve 242 which are referred to as one-way flow valves, are mechanically placed in the "open" state, without external power or influence, due to the flow produced by the coolant module 230 and the pump 246, respectively. In such arrangement, the cooling circuit 220 coupled between the inlet 206 and the outlet 208 of the liquid cooler 204 comprises a liquid cooled section 250 and an air cooled section 260 coupled in parallel to provide dual circulation paths for the liquid coolant of the liquid cooler 204. The liquid cooled section 250 as surrounded by the dotted line comprises the line 222, the first check valve 224 and the line 228 which connect the liquid cooler 204 to the coolant module 230, and the liquid coolant flowing in the liquid cooled section 250 is liquid cooled by the coolant module 230. The air cooled section 260, comprising the pump 246, the air cooled heat exchanger 244 with fan 248 and the second check valve 242, provides air cooling to the liquid coolant flowing in the air cooled section 260.

[0027] In operation, the controller 240 coupled to the cooling circuit 220 is configured to detect a failure of the liquid cooling and then select the liquid cooled section 250 and air cooled section 260 to operate in an operation mode or an idle mode accordingly. The failure of the liquid cooling may include, but not limited to, a loss of cooling function and a flow blockage. In one embodiment, upon the detection of the liquid cooling failiure, the controller 240 enables the operation of the air cooled section 260 by activating the pump 246 and the fan 248. The second check valve 242 is in the "open" state due to the flow produced by the activated pump 246 to allow the coolant flow of the liquid cooler 204 in the air cooled section 260, thereby providing air cooling. As the liquid coolant flowing out of the air cooled section 260 is on the downstream side of the first check valve 224, the first check valve 224 can prevent the backflow of the liquid coolant, e.g., to the circulation path (not illustrated) of the cooling system 200 for cooling gradient amplifier and/or radio frequency amplifier of an MRI equipment. When the air cooling is in the operation mode, the liquid cooling can be placed in the operation mode or the idle mode based on a determined failure mode of the liquid cooling. In one embodiment, when the failure of the liquid cooling leads to a higher temperature coolant flowing into the inlet 206 of the liquid cooler 204, it is required to deactivate the coolant circulation in the liquid cooling, since the higher temperature coolant will negatively affect the performance of the air cooling. In an alternative embodiment, the liquid cooling and air cooling can both operate in the operation mode to enhance reliability and efficiency via redundancy design. In summary, the air cooling remains in operation or is activated from the idle mode to the opeartion mode to provide continuous cooling to the superconducting magnetic coils, when there exists a failure with the liquid cooling. When the proper maintenance and repair of the liquid cooling is completed, the controller 240 places the air cooled section 260 back to the idle mode or remains in the operation mode. In the idle mode of the air cooled section 260, the pump 246 and the fan 248 are inactivated, and the second check valve 242 is in "closed" state due to lack of the flow produced by the pump 246. The first check valve 224 is in the "open" state due to the flow produced by the coolant module 230 to allow the coolant flow to the inlet 206 of the liquid cooler 204. The second check valve 242 in the "closed" shuts off the coolant flow from downstream outlet of the first check valve 224 to the air cooled heat exchanger 244.

[0028] In summary, to enhance the cooling reliability, the cooling system 200 provides a cooling circuit 220 comprising the liquid cooled section 250 and the air coole section 260 coupled in parallel, allowing redundant liquid cooling and air cooling combination or activation of backup air cooling when a failure the liquid cooling is detected.

[0029] FIG. 3 illustrates another example of a cooling system 300 according to one embodiment of the present invention. Components similar with or identical to those in FIG. 2 will not herein described in details. In the embodiment of FIG. 3, the coolant module 230 further comprises a condensing module 310 and a refrigeration module 320. The cold liquid coolant flowing out of the refrigeration module 320 are transported to the water-cooled compressor module 210 and other water-cooled components through a liquid cooling circuit that comprises pumps, water pipelines, and check valves. As illustrated in the liquid cooling of the cooling circuit 330 in FIG. 3, a pump 332 is coupled in line 334 to transfer the cold coolant flowing out of the refrigeration module 320 to the inlet 206 of the liquid cooler 204 through the first check valve 224. In the cooling system 300, heat from the water-cooled compressor module 210 is transferred by two-stage cooling of evaporation and condensation in the coolant system 230. In the first stage of the cooling, heat from the water-cooled compressor module 210 is transferred to the refrigeration module 320 by evaporator 322 and the liquid cooling circuit of the cooling circuit 330 flowing through the evaporator 322. The liquid cooling circuit of the cooling circuit 330 is also referred to as a secondary coolant loop. As a result of the first-stage heat transfer, working medium of the refrigeration module 320 with low temperature and low pressure in liquid-phase is heated to a gas-phase. Through a compressor 324 in the refrigeration module 320, the working medium in gas-phase flowing out of the evaporator 322 is compressed up to a much higher temperature and pressure. With the working medium of high temperature and pressure, the second stage of heat transfer happens at condenser 312 by liquefying the high-pressure and high-temperature working medium in gas-phase that leaves the compressor 324. Finally, the heat transferred to the condensing module 310 can be dissipated to outdoor. The condensing module 310 is also referred to as primary coolant loop. The two-stage cooling provides a compacter structure of heat transfer, which will be described in more details with reference to FIG. 4. Such liquid cooling with two-stage heat transfer and arranged in a single cabinet is referred to as an integrated liquid cooling cabinet. It shall be understood by the skilled in the art that the redundant or backup air cooling is readily appliable to liquid cooling comprising a water chiller and a traditional liquid cooling cabinet (LCC). The specific structure of LCC irrelevant to the present invention is not described in details and only those components relevant to the present invention are described in above description with reference to accompanying drawings.

[0030] FIG. 4A illustrates a schematic diagram of an integrated liquid cooling cabinet 400 according to one embodiment of the present invention. The integrated liquid cooling cabinet 400 comprises a cabinet 402 in the shape of a cuboid. The cabinet 402 has an open housing 403 defined by a base wall 412, opposite side walls 414 and 416 extending upwardly from side edges of the base wall 412, and a top wall 418 connected to the upper ends of the side walls 414 and 416 to define an interior of the cabinet 402. In the embodiment of FIG. 4A, a front access opening defining an access to the interior of the cabinet 402 can be closed by a door panel 420, as shown in FIG. 4B. The door panel 420 can be pivotally attached to either or both of the side walls 414 and 416. The cabinet 402 sits next to and separated from a wall of a room by a predetermined space, with the rear side of the cabinet 402 left exposed. The interior of the cabinet 402 is further separated into a first chamber 404 and a second chamber 406 by a separating wall 408 extending between the top wall 418 and the base wall 412. The air cooled section 260 of the cooling circuit 330, namely the air cooled heat exchanger 244 with the fan 248 is arranged in the first chamber 404. The remaining components of the cooling system 300, namely the coolant module 230, the liquid cooling section 250 of the cooling loop 330, the controller 240, and the liquid cooled compressor module 210, are arranged in the second chamber 406. When the air cooled section 260 operates in the operation mode, the cold intake air from the predetermined space at the rear side of the cabinet 402 is taken into the first chamber 404. Hot exhaust air is exhausted through a lot of openings arranged on the section of the door panel 420 that closes the front access to the first chamber 404. Owing to the separating wall 408, the hot exhaust air cannot enter the second chamber 406 and therefore cannot be taken in from the intake side of the air cooled section 260. As such, hot air recirculation can be eliminated.

[0031] In the embodiment of the integrated liquid cooling cabinet 400 in FIG. 4A, the liquid cooled compressor module 210 can be wheeled into the second chamber 406 and placed on the base wall 412 of the cabinet 402 next to the separating wall 408. The refrigeration module 320 of the coolant module 230 is positioned on the base wall of the cabinet 402 between the liquid cooled compressor module 210 and the side wall 416 of the cabinet 402. In the middle of the second chamber 406, an electric box 410 enclosing the controller 240 and other electric components, e.g., inverter, electric actuator, etc., are arranged above the liquid cooled compressor module 210. Primary and secondary coolant loops are arranged in the remaining space of the second chamber 406. More specifically, the condensing module 310, also referred to as primary coolant loop, is positioned in the middle of the second chamber 406 at the rear of the electric box 410, as shown in dotted line in FIG. 4A. Secondary coolant loop is arranged above the electric box 410. As such, the entire cooling can be realized by cheap components residing in a single cabinet 402. Benefiting from compact structure and elimination of expensive water chiller, the integrated liquid cooling cabinet 400 provides a cost-effective and small footprint cooling solution to MRI. It can be contemplated by the skilled in the art that, alternatively, a rear wall with openings can also allow the intake of cold air from the predetermined space. It is also contemplated that two or more door panels with each attached to a respective side wall can also be placed in either an open position or close position to open or close the front access opening. It is also contemplated by the skilled in the art that the gist of the invention is readily applicable to other cooling system, e.g., a cooling system with a water chiller and a liquid cooling cabinet (LCC), by placing the air cooled heat exchanger with the fan into a dedicated chamber separated from the remaining space of the LCC and carefully designing the air intake and air exhaust direction of the air cooling.

[0032] FIG. 5 illustrates an example of a cooling system 500 according to another embodiment of the present invention. In the embodiment of FIG. 5, a line 522 coupled to the outlet 232 of the coolant module 230 for flowing in the cold coolant is connected in series with the air cooled heat exchanger 260 before the cold coolant flows into the inlet 206 of the liquid cooler 204. In one embodiment, both the liquid cooling and the air cooling can be activated to operate such that redundant cooling can ensure continuous and reliable operation of the cooling system 500 even if a failure happens to the liquid cooling. Alternatively, the air cooling is used as a backup cooling solution which is activated by switching on the fan 248 only when a failure of the liquid cooling is detected. It is understood by the skilled in the art that the serially connected liquid and air cooling combination provides a more cost-effective and simply cooling system. However, when there is a flow blockage in the coolant circulation path, the cooling system 500 will encounter a failure. In view that the flow blockage does not happen frequently, the cooling system 500 is still attractive due to its low cost, compact structure and relatively reliable performance.

[0033] FIG. 6 illustrates a method of cooling a MRI system according to one embodiment of the present invention. FIG. 6 is described in connection with the cooling system 200 in FIG. 2. In step 602, the coolant module 230 provides a liquid coolant from its outlet 232. In step 604, the cooling circuit 220 with a combination of liquid cooling and air cooling directs the liquid coolant from the outlet 232 to the inlet 206 of the liquid cooler 204 of the compressor module 210. In step 606, heat generated by the compressor module 210 is dissipated by the liquid cooler 204 to the liquid coolant. In step 608, the heated liquid coolant is directed from the outlet 208 of the liquid cooler to the inlet 234 of the coolant module. In step 610, the controller 240 detects a failure of the liquid cooling, and in step 612, the controller 240 determines the liquid cooling and the air cooling to operate either in an operation mode or an idle mode upon detecting the failure of the liquid cooling.

[0034] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope. Further, for the sake of clearness, not all elements in the drawings may have been supplied with reference signs.

Claims

1. A cooling system (200) for an imaging system, comprising:

a compressor module (210) that comprises a liquid cooler (204);

a cooling circuit (220) coupled between an inlet (206) and an outlet (208) of the liquid cooler (204) and configured to provide a circulation path for circulating liquid coolant of the liquid cooler (204) between the inlet (206) and the outlet (208), wherein the cooling circuit (220) comprises a liquid cooled section (250) and an air cooled section (260), and wherein the liquid coolant flowing in the liquid cooled section (250) is liquid cooled and the liquid coolant flowing in the air cooled section (260) is air cooled; and

a controller (240) coupled to the cooling circuit (220) and configured to detect a failure of liquid cooling and to determine the liquid cooled section and/or the air cooled section to operate either in an operation mode or an idle mode upon detecting the failure of liquid cooling.

2. The cooling system of claim 1, wherein the liquid cooled section (250) is coupled in parallel with the air cooled section (260), wherein the liquid cooled section (250) comprises a first line (222) extending from an outlet (232) of a coolant module (230) to an upstream inlet of a first check valve (224), the first check valve (224), a second line (226) extending from a downstream outlet of the first check valve (224) to the inlet (206) of the liquid cooler (204), and a third line (228) extending from the outlet (208) of the liquid cooler (204) to an inlet (234) of the coolant module (230); and wherein the air cooled section (260) comprises a second check valve (242), an air cooled heat exchanger (244) with a fan (248), and a pump (246) connected in series between the inlet (206) and the outlet (208) of the liquid cooler (204).

3. The cooling system of claim 2, wherein the coolant system (230) further comprises:

a refrigeration module (320) configured to convert a working medium in liquid-phase into gas-phase and compress the working medium in the gas-phase up to a higher pressure and a higher temperature; and

a condensing module (310) coupled to the refrigeration module (320) to liquefying the high-pressure and high-temperature working medium in the gas-phase.

4. The cooling system of claim 1, wherein the first and second check valves (224, 242) passively control a flow direction of the liquid coolant in the cooling circuit (220) based on the determined mode of operation of the liquid cooled section and the air cooled section.

5. The cooling system of any of the claims 1 to 4, further comprising:
a cabinet (402) having a housing (404) defined by a base wall (412), opposite side walls (414, 416) extending upwardly from side edges of the base wall (412) and a top wall (418) connected to upper ends of the side walls (414, 416), wherein the housing (404) of the cabinet (402) is configured to define an interior of the cabinet (402), wherein a front access opening which defines an access to the interior of the cabinet (402) is configured to be closed by a door panel (420) attached to at least one of the side walls (414, 416); and
a separating wall (408) extending between the top wall (418) and the base wall (412) and spaced apart from the side walls (414, 416) and configured to divide the interior of the cabinet (402) into a first chamber (404) and a second chamber (406), and wherein the air cooled section is positioned in the first chamber (404) and the remaining components of the cooling system are positioned in the second chamber (406).

6. The cooling system of claim 5, wherein a part of the door panel (420) covering the first chamber (404) has a plurality of openings and configured to serve as an air exhaust side of the air cooling.

7. The cooling system of claim 5 or claim 6, wherein the cabinet (402) does not have a rear wall and the rear of the cabinet (402) is configured to serve as an air intake side of the air cooling.

8. The cooling system of any of the claims 5 to 7, wherein the compressor module (210) is configured to be wheeled into the cabinet (402).

9. The cooling system of claim 1, wherein the cooling circuit (220) comprises an air cooled heat exchanger (244) with a fan (248), a line (522) coupled between an outlet (232) of a coolant module (230) and the air cooled heat exchanger (244), and a line (524) coupled between the air cooled heat exchanger (244) and the inlet (206) of the liquid cooler (204), providing a combination of liquid cooling and air cooling coupled in series.

10. A method of cooling an imaging system comprising the steps of:

providing a liquid coolant from an outlet (232) of a coolant module (230);

directing the liquid coolant from the outlet (232) of the coolant module (230) to an inlet (206) of a liquid cooler (204) of a compressor module (210) through a cooling circuit (220) with a combination of liquid cooling and air cooling;

dissipating heat generated by the compressor module (210) by the liquid cooler (204) to the liquid coolant;

directing the heated liquid coolant from an outlet (208) of the liquid cooler (204) to an inlet (234) of the coolant module (230);
d etecting a failure of liquid cooling; and

determining the liquid cooling and/or the air cooling to operate either in an operation mode or an idle mode upon detecting the failure of liquid cooling.

11. The method of claim 10, further comprising: passively controlling a flow direction of the liquid coolant in the cooling circuit (220) based on the determined mode of operation of the liquid cooling and the air cooling by a first and second check valves (224, 242) respectively positioned in the liquid cooling and air cooling.

12. The method of claim 10 or claim 11, further comprising:

arranging the compressor module (210), the cooling circuit (220), and the coolant module (230) in an interior of a cabinet (402); and

dividing the interior of the cabinet (402) into a first chamber (404) and a second chamber (406) by a separating wall (408).

13. A magnetic resonance imaging system comprising a cooling system according to any of the claims 1 to 9 and/or wherein a method of cooling according to any of the claims 10 to 12 is implemented.

Drawing