WO2023225930A1

WO2023225930A1 - Valve arrangement for refrigerant compressor

Info

Publication number: WO2023225930A1
Application number: PCT/CN2022/095184
Authority: WO
Inventors: Brandon PRITCHARD; Lina Cao; Carl David FITCH
Original assignee: Danfoss A/S; Lina Cao
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2023-11-30

Abstract

In some aspects, the techniques described herein relate to a refrigerant compressor, including: a first cooling line configured to cool power electronics; a second cooling line configured to cool a motor of the compressor; a first valve operable to selectively restrict flow through the first cooling line, wherein the first valve is mounted to a baseplate; and a second valve operable to selectively restrict flow through the second cooling line, wherein the second valve is mounted to the baseplate.

Description

VALVE ARRANGEMENT FOR REFRIGERANT COMPRESSOR

BACKGROUND

Refrigerant compressors are used to circulate refrigerant in a chiller or heat pump via a refrigerant loop. Refrigerant loops are known to include a condenser, an expansion device, and an evaporator. Some compressors provide cooling to the motor and/or associated power electronics by conveying refrigerant from the main loop to the motor and/or other power electronics.

SUMMARY

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein fluid flowing into the first and second valves is from a common source.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein: the baseplate includes an inlet orifice and a first conduit connected to the inlet orifice, and the first conduit leads to a junction configured to direct some flow from the first conduit toward the first valve and other flow to the second valve.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein: a first inlet conduit connects the first valve and the junction, and a second inlet conduit connects the second valve and the junction.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein: the baseplate includes a first outlet orifice, a first outlet conduit connects the first valve and the first outlet orifice, the baseplate includes a second outlet orifice, and a second outlet conduit connects the second valve and the second outlet orifice.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein: a first rib connects the inlet orifice to the first outlet orifice, a second rib connects the inlet orifice to the second outlet orifice, and the first and second ribs project outward of a remainder of a surface of the baseplate.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein the baseplate is brass.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein the baseplate is mounted within a power electronics housing of the refrigerant compressor.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein the baseplate includes openings configured to receive fasteners.

In some aspects, the techniques described herein relate to a refrigerant compressor, wherein the first and second valves are electronic expansion valves.

In some aspects, the techniques described herein relate to a refrigerant system, including: a main refrigerant loop in communication with a condenser, an evaporator, and a compressor, wherein the compressor includes: a first cooling line configured to cool power electronics; a second cooling line configured to cool a motor of the compressor; a first valve operable to selectively restrict flow through the first cooling line, wherein the first valve is mounted to a baseplate; and a second valve operable to selectively restrict flow through the second cooling line, wherein the second valve is mounted to the baseplate.

In some aspects, the techniques described herein relate to a refrigerant system, wherein fluid flowing into the first and second valves is from a common source.

In some aspects, the techniques described herein relate to a refrigerant system, wherein: the baseplate includes an inlet orifice and a first conduit connected to the inlet orifice, and the first conduit leads to a junction configured to direct some flow from the first conduit toward the first valve and other flow to the second valve.

In some aspects, the techniques described herein relate to a refrigerant system, wherein: a first inlet conduit connects the first valve and the junction, and a second inlet conduit connects the second valve and the junction.

In some aspects, the techniques described herein relate to a refrigerant system, wherein: the baseplate includes a first outlet orifice, a first outlet conduit connects the first valve and the first outlet orifice, the baseplate includes a second outlet orifice, and a second outlet conduit connects the second valve and the second outlet orifice.

In some aspects, the techniques described herein relate to a refrigerant system, wherein: a first rib connects the inlet orifice to the first outlet orifice, a second rib connects the inlet orifice to the second outlet orifice, and the first and second ribs project outward of a remainder of a surface of the baseplate.

In some aspects, the techniques described herein relate to a refrigerant system, wherein the baseplate is brass.

In some aspects, the techniques described herein relate to a refrigerant system, wherein the baseplate is mounted within a power electronics housing of the refrigerant compressor.

In some aspects, the techniques described herein relate to a refrigerant system, wherein the baseplate includes openings configured to receive fasteners.

In some aspects, the techniques described herein relate to a refrigerant system, wherein the first and second valves are electronic expansion valves.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic illustration of a refrigerant loop.

Figure 2 is a schematic illustration of an example compressor cooling arrangement.

Figure 3 is a close up view of an example valve arrangement.

Figure 4 is a partially broken view of a compressor, and in particular illustrates an exemplary mounting location for the valve arrangement of Figure 3.

Figure 5 is a partially broken view of one of the valves of Figure 3.

DETAILED DESCRIPTION

Figure 1 schematically illustrates a refrigerant cooling system 10. The refrigerant system 10 includes a main refrigerant loop, or circuit, 12 in communication with a compressor or multiple compressors 14, a condenser 16, an evaporator 18, and an expansion device 20. This refrigerant system 10 may be used in a chiller or heat pump, for example. Notably, while a particular example of the refrigerant system 10 is shown, this application extends to other refrigerant system configurations. For instance, the main refrigerant loop 12 can include an economizer downstream of the condenser 16 and upstream of the expansion device 20. The refrigerant cooling system 10 may be an air condition system, for example.

Figure 2 schematically illustrates an example compressor 14. The example compressor 14 is a two-stage compressor. A first impeller 22 is upstream of a second impeller 24. The example compressor 14 is a two stage centrifugal compressor. Other multiple-stage compressors may be utilized in other embodiments. In some embodiments, one stage includes an impeller and shroud arrangement, and another stage includes an alternative arrangement. The

impellers

22, 24 are driven by a motor 26.

The compressor 14 may be a split cooling compressor. A first cooling line 30 draws cooling fluid from the main refrigerant loop 12 (shown in Figure 1) for the power electronics, such as an insulated-gate bipolar transistor (IGBT) and a silicon controlled rectifier (SCR) , for example. In the illustrated example, the cooling line 30 has a first heat exchanging portion 31 for cooling an IGBT and a second heat exchanging portion 35 for cooling an SCR. A second cooling line 80 from the main refrigerant loop 12 cools the motor 26, for example. A first valve 29 may be in communication with a first controller 38 to control the fluid entering the first cooling line 30. A second valve 79 may be in communication with a second controller 78 to control the fluid entering the second cooling line 80. Although illustrated as two controllers 38, 78, it should be understood that a single controller may be used for both

cooling lines

30, 80. Either or both of the controllers 38, 78 may be provided by a bearing motor compressor controller (BMCC) . The controller 78 may be in communication with

sensors

84, 86 arranged along the cooling line 80, for example. In the illustrated example, a first temperature sensor 84 provides a temperature at the motor windings and a second temperature sensor 86 provides a temperature at the motor cavity.

The cooling line 30 returns the cooling fluid to the main refrigerant loop 12 near the compressor 14. In this example, the cooling line 30 is selectable to return the cooling fluid to one of at least two places at a juncture 32. The cooling line 30 may be configured in a first mode or a second mode. In the first mode, the cooling line 30 is configured to return cooling fluid via a first line 34 that returns, or dumps, cooling fluid between the first and

second impellers

22, 24. This is known as an inter-stage return, in some examples. In the second mode, the cooling line 30 is configured to return cooling fluid via a second line 36 upstream of the first impeller 22. Specifically, the second line 36 may return fluid to the evaporator 18 or directly into the suction side of the compressor 14.

The first and second modes may be selected manually or automatically. The first mode may be used for regular comfort cooling applications, while the second mode may be used for high saturated suction temperature (SST) cooling applications, such as data centers. In some examples, the controller 38 is used to switch between the first and second modes. The controller 38 may be in communication with

sensors

40, 42 arranged along the cooling line 30, for example. In the illustrated example, a first temperature sensor 40 provides a temperature at the IGBT and a second temperature sensor 42 provides a temperature at the SCR. In one embodiment, a directional flow control valve 33 is used to switch between the first mode and the second mode.

The controller 38 may monitor the suction pressure of the compressor 14, in some examples. In some examples, the controller 38 will direct the valve 33 to return the cooling fluid via the second line 36 if the suction pressure of the compressor 14 is above a preset value. This is the second mode with a suction return. If the suction pressure is below the preset value, the valve 33 will return the cooling fluid via the first line 34. This is the first mode inter-stage return. The first mode may be the default mode, for example.

The controller 38 may monitor the pressure difference in the cooling line and

temperature sensors

40 and 42 in real time. In case of low-pressure difference and the temperature sensor readings continuously above the set points, the controller 38 can direct the valve 33 to return to the second line 36. If the pressure difference is enough to keep the temperature set points, it can direct the return to 34 to increase the total system efficiency.

Figure 3 illustrates an exemplary arrangement of the first and

second valves

29, 79. In this example, the first and

second valves

29, 79 are mounted to a baseplate 90 which may be made of brass, in one example. The baseplate 90 includes various openings 91 for connection to fluid conduits and for the receipt of fasteners, such that the baseplate 90 facilitate both fluid and mechanical connections to the compressor 14. In one example, the baseplate 90 and first and

second valves

29, 79 can be mounted to the compressor 14 generally in the location shown in Figure 4. The baseplate 90 is mounted adjacent and within the power electronics housing 92 of the compressor 14, in this example.

With continued reference to Figure 3, the baseplate 90 includes an inlet orifice 94 and first and second outlet orifices 96, 98. The

orifices

94, 96, 98 each include flanges that project outward from a remainder of the surface S of the baseplate 90, which is substantially planar. The flanges of the

orifices

94, 96, 98 facilitate connections between the baseplate 90 and fluid conduits. Further, first and

second ribs

100, 102 project outward from the remainder of surface S the baseplate 90 to provide rigidity to the flanges of the

orifices

94, 96, 98, and, in turn, to add rigidity to the overall arrangement of Figure 3.

In the example, a first conduit 104 is attached to the inlet orifice 94. The first conduit 104 leads to a junction 106. The first conduit 104 and junction 106 could be one integral structure, such as a three-way brass tube, in one example. At the junction 106, fluid splits and is fed along first and

second inlet conduits

108, 110, which respectively lead to the first and

second valves

29, 79, respectively. The direction of fluid flow is generally represented by the relatively thick arrows in Figure 3. Downstream of the first and

second valves

29, 79, the arrangement includes first and

second outlet conduits

112, 114, which lead from respective first and

second valves

29, 79 to first and second outlet orifices 96, 98. The first outlet orifice 96 is fluidly coupled to the cooling line 30, and the second outlet orifice 98 is fluidly coupled to the cooling line 80, as generally shown in Figure 2.

Each of the

conduits

104, 108, 110, 112, 114 may be joined to the baseplate 90, junction 106, and first and

second valves

29, 79 by brazing, in one example. Alternative attachment techniques come within the scope of this disclosure. The arrangement of Figure 3 is relatively easy to manufacture, easy to assemble, low cost, and withstands high fluid pressures. The arrangement also provides a greater level of adjustability relative to arrangements with mere solenoid (i.e., on-off) valves. In turn, the compressor 14 exhibits greater cooling capacity and a reduction in energy consumption, thereby improving efficiency of the refrigerant system 10 overall.

Figure 5 illustrates the first valve 29 in cross-section. The second valve 79 is substantially identical. Generally, the first and

second valves

29, 79 are not solenoid, or on-off, valves in this disclosure. Rather, the first and

second valves

29, 79 are adjustable. The first and

second valves

29, 79 are selectively controlled to expand fluid such that fluid directed to through the outlet conduits 114, 116 is low pressure, low temperature fluid compared to fluid upstream of the first and

second valves

29, 79. The first and

second valves

29, 79 may be electronic expansion valves (EEVs or EXVs) . In a particular example, the first and

second valves

29, 79 are provided by ETS 5M valves.

With reference to Figure 5, the first valve 29 includes an orifice plate 117 with a narrow opening 118 between the first inlet conduit 108 and the first outlet conduit 112. A plunger 120 having a projection sized and shaped to fit into the opening 118 is selectively moveable toward and away from the opening 118 via motor 122 to selectively open and close the valve 29. Specifically, the plunger 120 can move to a fully closed position, a fully open position, and a nearly infinite number of positions in between. In this regard, the first valve 29 may be considered infinitely adjustable.

It should be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure.

Although the different examples have the specific components shown in the illustrations, embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from one of the examples in combination with features or components from another one of the examples.

One of ordinary skill in this art would understand that the above-described embodiments are exemplary and non-limiting. That is, modifications of this disclosure would come within the scope of the claims.

Claims

A refrigerant compressor, comprising:

a first cooling line configured to cool power electronics;

a second cooling line configured to cool a motor of the compressor;

a first valve operable to selectively restrict flow through the first cooling line, wherein the first valve is mounted to a baseplate; and

a second valve operable to selectively restrict flow through the second cooling line, wherein the second valve is mounted to the baseplate.
The refrigerant compressor as recited in claim 1, wherein fluid flowing into the first and second valves is from a common source.
The refrigerant compressor as recited in claim 1, wherein:

the baseplate includes an inlet orifice and a first conduit connected to the inlet orifice, and

the first conduit leads to a junction configured to direct some flow from the first conduit toward the first valve and other flow to the second valve.
The refrigerant compressor as recited in claim 3, wherein:

a first inlet conduit connects the first valve and the junction, and

a second inlet conduit connects the second valve and the junction.
The refrigerant compressor as recited in claim 4, wherein:

the baseplate includes a first outlet orifice,

a first outlet conduit connects the first valve and the first outlet orifice,

the baseplate includes a second outlet orifice, and

a second outlet conduit connects the second valve and the second outlet orifice.
The refrigerant compressor as recited in claim 5, wherein:

a first rib connects the inlet orifice to the first outlet orifice,

a second rib connects the inlet orifice to the second outlet orifice, and

the first and second ribs project outward of a remainder of a surface of the baseplate.
The refrigerant compressor as recited in claim 1, wherein the baseplate is brass.
The refrigerant compressor as recited in claim 1, wherein the baseplate is mounted within a power electronics housing of the refrigerant compressor.
The refrigerant compressor as recited in claim 8, wherein the baseplate includes openings configured to receive fasteners.
The refrigerant compressor as recited in claim 1, wherein the first and second valves are electronic expansion valves.
A refrigerant system, comprising:

a main refrigerant loop in communication with a condenser, an evaporator, and a compressor, wherein the compressor includes:

a first cooling line configured to cool power electronics;

a second cooling line configured to cool a motor of the compressor;

a first valve operable to selectively restrict flow through the first cooling line, wherein the first valve is mounted to a baseplate; and

a second valve operable to selectively restrict flow through the second cooling line, wherein the second valve is mounted to the baseplate.
The refrigerant system as recited in claim 11, wherein fluid flowing into the first and second valves is from a common source.
The refrigerant system as recited in claim 11, wherein:

the baseplate includes an inlet orifice and a first conduit connected to the inlet orifice, and

the first conduit leads to a junction configured to direct some flow from the first conduit toward the first valve and other flow to the second valve.
The refrigerant system as recited in claim 13, wherein:

a first inlet conduit connects the first valve and the junction, and

a second inlet conduit connects the second valve and the junction.
The refrigerant system as recited in claim 14, wherein:

the baseplate includes a first outlet orifice,

a first outlet conduit connects the first valve and the first outlet orifice,

the baseplate includes a second outlet orifice, and

a second outlet conduit connects the second valve and the second outlet orifice.
The refrigerant system as recited in claim 15, wherein:

a first rib connects the inlet orifice to the first outlet orifice,

a second rib connects the inlet orifice to the second outlet orifice, and

the first and second ribs project outward of a remainder of a surface of the baseplate.
The refrigerant system as recited in claim 11, wherein the baseplate is brass.
The refrigerant system as recited in claim 11, wherein the baseplate is mounted within a power electronics housing of the refrigerant compressor.
The refrigerant system as recited in claim 18, wherein the baseplate includes openings configured to receive fasteners.
The refrigerant system as recited in claim 11, wherein the first and second valves are electronic expansion valves.