Magnetic levitation double-machine single-system water chiller

Abstract

The utility model discloses a cold water set of magnetic suspension double machine single system. The first magnetic suspension type centrifugal compressor is linked with the condenser in it, the condenser is linked with the economizer, the economizer is linked with the first magnetic suspension type centrifugal compressor, the first electric ball valve is established between the economizer and the first magnetic suspension type centrifugal compressor, the controller controls the first electric ball valve to close first, controls the first magnetic suspension type centrifugal compressor to execute the machine reduction stoppage operation again. Utilize the controller to be connected with the first magnetic suspension type centrifugal compressor, the first electric ball valve communication respectively, after the first electric ball valve closes, the first magnetic suspension type centrifugal compressor executes the machine reduction stoppage operation again, can avoid gaseous refrigerant in the economizer to enter the first magnetic suspension type centrifugal compressor, can prevent the first magnetic suspension type centrifugal compressor reverse rotation, can avoid the rotor of the first magnetic suspension type centrifugal compressor deflection too much, also can reduce the maintenance cost.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of compressor oil -free system, especially in a kind of magnetic levitation double-machine single system's water chilling unit. BACKGROUND

[0002] Compressor is a driven fluid machine that lifts low-pressure gas to high-pressure gas. Compressor is widely used in air conditioning, heat pump, ice storage and other industries.

[0003] Magnetic levitation centrifugal compressor is a kind of compressor, and the magnetic levitation centrifugal compressor is usually a high-efficiency energy-saving equipment using magnetic suspension bearing technology. The core component is a magnetic levitation centrifugal compressor. The magnetic levitation centrifugal compressor suspends the rotor by magnetic field, avoids mechanical contact and friction, thereby significantly reduces energy consumption and noise, and improves service life and reliability.

[0004] The magnetic levitation compressor rotor has the characteristics of no contact and no friction with the bearing during suspension or operation. When it stops, the high-pressure gaseous refrigerant flows to low pressure, forming gas backflow. The magnetic levitation centrifugal compressor is prone to reverse rotation due to gas backflow, which causes noise and vibration, and even damages the bearing, impeller, sealing ring and other parts, seriously affecting the normal operation and service life of the compressor. UTILITY MODEL CONTENTS

[0005] The utility model solves the technical problem that the magnetic levitation compressor rotor is prone to reverse rotation during shutdown in the prior art, and provides a magnetic levitation double-machine single system's water chilling unit.

[0006] The utility model solves the above technical problems by the following technical solutions:

[0007] A magnetic levitation double-machine single system's water chilling unit, the magnetic levitation double-machine single system's water chilling unit includes: first magnetic levitation centrifugal compressor, condenser, economizer, evaporator, first electric ball valve and controller, the exhaust port of the first magnetic levitation centrifugal compressor is communicated with the condenser;The condenser is communicated with the economizer, and the economizer is communicated with the first magnetic levitation centrifugal compressor;The evaporator is communicated with the economizer, and the evaporator is also communicated with the first magnetic levitation centrifugal compressor;The first electric ball valve is arranged between the economizer and the first magnetic levitation centrifugal compressor;The controller is respectively communicated with the first magnetic levitation centrifugal compressor, the first electric ball valve;The controller sends the first electric ball valve closing instruction first, and the first electric ball valve executes closing operation after receiving the closing instruction;The controller sends the first magnetic levitation centrifugal compressor reduction machine shutdown instruction again, and the first magnetic levitation centrifugal compressor executes reduction machine shutdown operation after receiving the reduction machine shutdown instruction.

[0008] In the scheme, by adopting the above structure, the controller is in communication connection with the first magnetic suspension centrifugal compressor and the first electric ball valve respectively, the first magnetic suspension centrifugal compressor performs the machine reduction shutdown operation again after the first electric ball valve is closed, the gaseous refrigerant in the economizer can be avoided from entering the first magnetic suspension centrifugal compressor, the first magnetic suspension centrifugal compressor can be prevented from being reversed, the rotor of the first magnetic suspension centrifugal compressor can be avoided from being excessively deflected, the risk of leakage can be reduced, and the maintenance cost can be reduced.

[0009] Optionally, the magnetic suspension double-machine single-system water chiller further comprises a second magnetic suspension centrifugal compressor and a second electric ball valve, the second magnetic suspension centrifugal compressor is connected in parallel with the first magnetic suspension centrifugal compressor, and the evaporator is further connected in communication with the second magnetic suspension centrifugal compressor; the second electric ball valve is arranged between the economizer and the second magnetic suspension centrifugal compressor; and the controller is in communication connection with the second magnetic suspension centrifugal compressor and the second electric ball valve respectively.

[0010] Optionally, the first magnetic suspension centrifugal compressor performs the machine reduction shutdown operation, and the second magnetic suspension centrifugal compressor performs the operation.

[0011] Optionally, the controller simultaneously sends a closing instruction to the first electric ball valve and the second electric ball valve respectively, and the first electric ball valve and the second electric ball valve perform closing operations after receiving the closing instruction; and the controller further sends a machine reduction shutdown instruction to the first magnetic suspension centrifugal compressor and the second magnetic suspension centrifugal compressor respectively, and the first magnetic suspension centrifugal compressor and the second magnetic suspension centrifugal compressor perform machine reduction shutdown operations after receiving the machine reduction shutdown instruction.

[0012] Optionally, the gaseous refrigerant evaporated by the evaporator enters the first magnetic suspension centrifugal compressor, the first magnetic suspension centrifugal compressor compresses the gaseous refrigerant, and the gaseous refrigerant compressed by the first magnetic suspension centrifugal compressor enters the condenser.

[0013] Optionally, an expansion valve is further arranged between the condenser and the economizer, and the refrigerant enters the economizer after being throttled by the expansion valve.

[0014] Optionally, the gaseous refrigerant flashed in the economizer enters the first magnetic suspension centrifugal compressor after passing through the first electric ball valve.

[0015] Optionally, an expansion valve is arranged between the economizer and the evaporator, and the refrigerant enters the evaporator after being throttled by the expansion valve.

[0016] On the basis of conforming to the common sense of the art, the above-mentioned preferred conditions can be combined arbitrarily, namely, the preferred examples of the present application are obtained.

[0017] The positive progress effect of the present application is that:

[0018] The first magnetic suspension type centrifugal compressor is executed to reduce machine stop operation after the first electric ball valve is closed, the gaseous refrigerant in the economizer can be avoided to enter the first magnetic suspension type centrifugal compressor, the first magnetic suspension type centrifugal compressor can be prevented from being reversed, the rotor of the first magnetic suspension type centrifugal compressor can be avoided to be excessively deflected, the risk of leakage can be reduced, and the maintenance cost can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a schematic view of the water chiller of the magnetic suspension double-machine single-system of the present application.

[0020] MARK NUMBER EXPLANATION:

[0021] The water chiller of the magnetic suspension double-machine single-system 100

[0022] The first magnetic suspension type centrifugal compressor 11

[0023] The second magnetic suspension type centrifugal compressor 12

[0024] The condenser 13

[0025] The economizer 14

[0026] The evaporator 15

[0027] The first electric ball valve 16

[0028] The second electric ball valve 17

[0029] The expansion valve 18 DETAILED DESCRIPTION

[0030] The present application will be more clearly and completely understood through the following examples combined with the drawings, but the present application is not limited in the scope of the examples.

[0031] For example, Figure 1As shown, the embodiment includes a magnetic suspension double-machine single-system water chiller 100, which comprises a first magnetic suspension centrifugal compressor 11, a condenser 13, an economizer 14, an evaporator 15, a first electric ball valve 16, and a controller. The exhaust port of the first magnetic suspension centrifugal compressor 11 is in communication with the condenser 13. The condenser 13 is in communication with the economizer 14, and the economizer 14 is in communication with the first magnetic suspension centrifugal compressor 11. The evaporator 15 is in communication with the economizer 14 and also in communication with the first magnetic suspension centrifugal compressor 11. The first electric ball valve 16 is arranged between the economizer 14 and the first magnetic suspension centrifugal compressor 11. The controller is in communication connection with the first magnetic suspension centrifugal compressor 11 and the first electric ball valve 16 respectively. The controller first sends a closing instruction to the first electric ball valve 16, and the first electric ball valve 16 executes the closing operation after receiving the closing instruction. Then, the controller sends a machine-reducing shutdown instruction to the first magnetic suspension centrifugal compressor 11, and the first magnetic suspension centrifugal compressor 11 executes the machine-reducing shutdown operation after receiving the machine-reducing shutdown instruction. By using the controller to be in communication connection with the first magnetic suspension centrifugal compressor 11 and the first electric ball valve 16 respectively, the gaseous refrigerant in the economizer 14 can be prevented from entering the first magnetic suspension centrifugal compressor 11 after the first electric ball valve 16 is closed, the first magnetic suspension centrifugal compressor 11 can be prevented from reversing, the rotor of the first magnetic suspension centrifugal compressor 11 can be prevented from excessive yawing, the risk of leakage can be reduced, and the maintenance cost can also be reduced. Figure 1 The controller is not shown in the figure.

[0032] The magnetic suspension double-machine single-system water chiller 100 further comprises a second magnetic suspension centrifugal compressor 12 and a second electric ball valve 17. The second magnetic suspension centrifugal compressor 12 is connected in parallel with the first magnetic suspension centrifugal compressor 11, and the evaporator 15 is also in communication with the second magnetic suspension centrifugal compressor 12. The second electric ball valve 17 is arranged between the economizer 14 and the second magnetic suspension centrifugal compressor 12. The controller is in communication connection with the second magnetic suspension centrifugal compressor 12 and the second electric ball valve 17 respectively.

[0033] The first magnetic suspension centrifugal compressor 11 executes the machine-reducing shutdown operation, and the second magnetic suspension centrifugal compressor 12 executes the operation. The second magnetic suspension centrifugal compressor 12 can continuously consume the gaseous refrigerant generated by the economizer 14.

[0034] The controller sends a closing instruction to the first electric ball valve 16 and the second electric ball valve 17 simultaneously, and the first electric ball valve 16 and the second electric ball valve 17 execute the closing operation after receiving the closing instruction. The controller sends a machine reduction and shutdown instruction to the first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12, respectively, and the first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12 execute the machine reduction and shutdown operation after receiving the machine reduction and shutdown instruction. The first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12 shut down at the same time, and the first electric ball valve 16 and the second electric ball valve 17 need to be closed before shutdown.

[0035] The evaporator 15 absorbs heat and evaporates the gaseous refrigerant into the first magnetic suspension centrifugal compressor 11. The first magnetic suspension centrifugal compressor 11 compresses the gaseous refrigerant, and the compressed gaseous refrigerant enters the condenser 13.

[0036] The condenser 13 and the economizer 14 are also provided with an expansion valve 18. The refrigerant passes through the expansion valve 18 to enter the economizer 14.

[0037] The gaseous refrigerant flashed in the economizer 14 enters the first magnetic suspension centrifugal compressor 11 through the first electric ball valve 16.

[0038] The economizer 14 and the evaporator 15 are provided with an expansion valve 18. The refrigerant passes through the expansion valve 18 to enter the evaporator 15.

[0039] The magnetic suspension dual-machine single-system water chiller 100 can avoid the reverse rotation of the first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12, thereby avoiding excessive bearing or rotor yaw, avoiding noise and vibration, and avoiding wear on internal parts. The magnetic suspension dual-machine single-system water chiller 100 can improve the control logic of the magnetic suspension centrifugal dual-machine single-system water chiller, prevent damage to bearings, sealing rings, impellers and other parts caused by the reverse rotation of the first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12 during shutdown, and improve the reliability of the water chiller operation.

[0040] The magnetic suspension double-machine single-system water chiller 100 improves the original control logic, and the control logic of the medium-pressure air supplementing switch valve is changed from being opened and closed simultaneously with the first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12 to being closed before the first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12 execute a shutdown command, so that the first magnetic suspension centrifugal compressor 11 and the second magnetic suspension centrifugal compressor 12 are completely closed before executing the shutdown command, and the control logic of the magnetic suspension double-machine single-system water chiller 100 has the following advantages: the disadvantage of slow reaction speed of the medium-pressure valve is avoided; the influence of the medium-pressure gaseous refrigerant on the rotor backflush is effectively avoided, the risk of reverse rotation is reduced, the maintenance cost in the later period is reduced, the service life of the equipment is prolonged, the leakage probability of the gaseous refrigerant is reduced, and no additional anti-reverse rotation device or anti-reverse rotation design is needed, so that the additional cost is reduced.

[0041] Although the specific embodiments of the present application are described above, those skilled in the art should understand that this is only an example, and the protection scope of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present application, and these changes and modifications all fall within the protection scope of the present application.

Claims

1. A magnetic levitation double-motor single-system water chiller, characterized in that, The magnetic suspension double-machine single-system water chiller comprises: a first magnetic suspension centrifugal compressor; a condenser, which is connected with the exhaust port of the first magnetic suspension centrifugal compressor; an economizer, which is connected with the condenser and the first magnetic suspension centrifugal compressor; an evaporator, which is connected with the economizer and the first magnetic suspension centrifugal compressor; a first electric ball valve, which is arranged between the economizer and the first magnetic suspension centrifugal compressor; a controller, which is in communication connection with the first magnetic suspension centrifugal compressor and the first electric ball valve respectively; the controller first sends a closing instruction to the first electric ball valve, and the first electric ball valve executes a closing operation after receiving the closing instruction; the controller then sends a machine-reducing shutdown instruction to the first magnetic suspension centrifugal compressor, and the first magnetic suspension centrifugal compressor executes a machine-reducing shutdown operation after receiving the machine-reducing shutdown instruction.

2. The magnetic levitation dual-machine single-system water chiller according to claim 1, characterized in that, The magnetic suspension double-machine single-system water chiller further comprises a second magnetic suspension centrifugal compressor and a second electric ball valve, the second magnetic suspension centrifugal compressor is connected in parallel with the first magnetic suspension centrifugal compressor, and the evaporator is further connected with the second magnetic suspension centrifugal compressor; the second electric ball valve is arranged between the economizer and the second magnetic suspension centrifugal compressor; and the controller is in communication connection with the second magnetic suspension centrifugal compressor and the second electric ball valve respectively.

3. The magnetic levitation dual-inverter single-system water chiller according to claim 2, characterized in that, The first magnetic suspension centrifugal compressor executes a machine-reducing shutdown operation, and the second magnetic suspension centrifugal compressor executes a running operation.

4. The magnetic levitation dual-inverter single-system water chiller according to claim 2, characterized in that, The controller first sends a closing instruction to the first electric ball valve and the second electric ball valve respectively, and the first electric ball valve and the second electric ball valve execute a closing operation respectively after receiving the closing instruction; the controller then sends a machine-reducing shutdown instruction to the first magnetic suspension centrifugal compressor and the second magnetic suspension centrifugal compressor respectively, and the first magnetic suspension centrifugal compressor and the second magnetic suspension centrifugal compressor execute a machine-reducing shutdown operation respectively after receiving the machine-reducing shutdown instruction.

5. The magnetic levitation dual-inverter single-system water chiller according to claim 1, characterized in that, The gaseous refrigerant evaporated by the evaporator enters the first magnetic suspension centrifugal compressor, and the gaseous refrigerant is compressed by the first magnetic suspension centrifugal compressor and then enters the condenser.

6. The magnetic levitation dual-inverter single-system water chiller according to claim 1, characterized in that, An expansion valve is further arranged between the condenser and the economizer, and the refrigerant enters the economizer after throttling through the expansion valve.

7. The magnetic levitation dual-inverter single-system water chiller according to claim 1, characterized in that, The gaseous refrigerant flashed in the economizer enters the first magnetic suspension centrifugal compressor through the first electric ball valve.

8. The magnetic levitation dual-inverter single-system water chiller according to claim 1, characterized in that, An expansion valve is arranged between the economizer and the evaporator, and the refrigerant enters the evaporator after throttling through the expansion valve.

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