Magnetic suspension centrifugal compressor unit and shutdown control system

Abstract

The utility model discloses a magnetic suspension centrifugal compressor unit and a shutdown control system, and relates to the technical field of compressors. The shutdown control system comprises a magnetic suspension bearing controller, a unit controller and a frequency converter, the magnetic suspension bearing controller comprises a first relay switch; the first relay switch is configured to be switched off in response to a first fault signal sent by the magnetic suspension bearing controller; the unit controller comprises a second relay switch; the second relay switch is configured to be switched off in response to a second fault signal sent by the unit controller; the frequency converter stops working when the first relay switch or the second relay switch is switched off, and the magnetic suspension bearing controller stops working after a set duration. The system can timely control the unit to stop working through the relay switch.

Description

Technical Field

[0001] The utility model relates to the technical field of compressors, in particular to a magnetic suspension centrifugal compressor unit and a shutdown control system. Background Art

[0002] The communication between the host computer, unit control controller, magnetic bearing controller and frequency converter in the magnetic levitation centrifugal compressor unit generally uses serial communication. However, the environment in which the magnetic levitation centrifugal compressor unit is located is complex, which may cause local communication instability or even disconnection of communication in the unit, making it impossible to issue a shutdown command through communication, resulting in the magnetic levitation bearing controller and frequency converter failing to shut down in time, affecting the reliability of the unit. Utility Model Content

[0003] Based on this, it is necessary to provide a magnetic levitation centrifugal compressor unit and a shutdown control system that can control the magnetic levitation centrifugal compressor unit to shut down in time in order to solve the above technical problems.

[0004] A shutdown control system for a magnetically suspended centrifugal compressor unit, comprising:

[0005] The magnetic bearing controller comprises a first relay switch; the first relay switch is configured to be disconnected in response to a first fault signal sent by the magnetic bearing controller; the unit controller comprises a second relay switch; the second relay switch is configured to be disconnected in response to a second fault signal sent by the unit controller;

[0006] The magnetic bearing controller and the unit controller are connected in series to the frequency converter via the load output end of the first relay switch and the load output end of the second relay switch; the frequency converter stops working when the first relay switch is disconnected or the second relay switch is disconnected, and the magnetic bearing controller stops working after a set time.

[0007] In the above scheme, the shutdown control system also includes a manual emergency stop switch, the load output end of the first relay switch and the load output end of the second relay switch are connected in series to the output end of the inverter; the load output end of the second relay switch and the manual emergency stop switch are connected in series to the input end of the inverter;

[0008] The frequency converter stops working when the manual emergency stop switch is disconnected, and the magnetic bearing controller stops working after a set time period.

[0009] In the above solution, the first relay switch is further configured to close in response to a floating signal received by the magnetic bearing controller;

[0010] The second relay switch is further configured to close in response to a start signal received by the group controller.

[0011] In the above solution, the first relay switch and the second relay switch are optocoupler relay switches.

[0012] In the above solution, the magnetic bearing controller starts timing when a shutdown signal is detected.

[0013] In the above solution, the shutdown signal is triggered when the first relay switch is disconnected.

[0014] In the above solution, the shutdown signal is triggered when the magnetic bearing controller detects that the suspension accuracy of the rotor is less than a set value.

[0015] In the above solution, the shutdown control system further includes an alarm module, which is respectively connected to the magnetic bearing controller and the unit controller, and the alarm module sends an alarm signal when detecting the first fault signal or the second fault signal.

[0016] In the above solution, the magnetic bearing controller and the unit controller use serial communication.

[0017] A magnetic levitation centrifugal compressor unit comprises: a magnetic levitation centrifugal compressor, a condenser, an evaporator and a shutdown control system of the magnetic levitation centrifugal compressor unit in the above scheme.

[0018] The above-mentioned magnetic levitation centrifugal compressor unit and shutdown control system are respectively equipped with a first relay switch and a second relay switch in the magnetic levitation bearing controller and the unit controller. The magnetic levitation bearing controller and the unit controller are connected in series to the frequency converter via the first relay switch and the second relay switch, wherein the first relay switch and the second relay switch are disconnected when a fault signal is present, so that when the first relay switch or the second relay switch is disconnected, the frequency converter and the magnetic levitation bearing controller can be controlled to stop working in time, thereby ensuring the reliability and safety of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a shutdown control system of a magnetic suspension centrifugal compressor unit in one embodiment;

[0020] Figure 2 The structure diagram of a shutdown control system of a magnetic suspension centrifugal compressor unit including a manual emergency stop switch in one embodiment;

[0021] Figure 3 Schematic diagram of the structure of a magnetic levitation centrifugal compressor unit in one embodiment. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0023] The implementation details of the technical solution of the embodiment of the utility model are described in detail below.

[0024] like Figure 1 As shown, Figure 1 The figure shows the structure diagram of the shutdown control system of the magnetic suspension centrifugal compressor unit. Figure 1 The shutdown control system 100 is composed of a magnetic bearing controller 10 , a unit controller 20 and a frequency converter 30 .

[0025] In this embodiment, the magnetic bearing controller 10 includes a first relay switch 101, which is configured to be disconnected in response to a first fault signal sent by the magnetic bearing controller 10, that is, when a fault occurs in the magnetic bearing controller 10, the first relay switch 101 is in an open state.

[0026] Likewise, the unit controller 20 includes a second relay switch 201 , which is configured to be disconnected in response to a second fault signal sent by the unit controller 20 .

[0027] In practical applications, the second fault signal is sent by the unit controller 20 when a fault is detected. Specifically, the unit controller 20 can communicate with the frequency converter 30 to obtain the fault condition of the frequency converter 30, and when it is confirmed that the frequency converter 30 has a fault condition, a second fault signal is sent to disconnect the second relay switch 201, that is, when the frequency converter 30 fails, the second relay switch 201 is in a disconnected state. Of course, the unit controller 20 can further communicate with the magnetic bearing controller 10 to obtain the fault condition of the magnetic bearing controller 10, and when it is confirmed that the magnetic bearing controller 10 has a fault condition, a second fault condition is sent to disconnect the second relay switch 201.

[0028] exist Figure 1In the figure, the magnetic bearing controller 10 and the unit controller 20 are connected in series to the inverter 30 via the load output terminal of the first relay switch 101 and the load output terminal of the second relay switch 201. The specific connection relationship can be: the load output terminal KPS2-2 of the second relay switch 201 is connected to the input terminal VIN of the inverter 30, and the load output terminal KPS1-1 of the first relay switch 101 is connected in series with the load output terminal KPS2-1 of the second relay switch 201, and then the load input terminal KPS1-2 of the first relay switch 101 is connected to the output terminal VOUT of the inverter 30.

[0029] Under this connection relationship, the first relay switch 101 and the second relay switch 201 act as switches in the circuit. When the first relay switch 101 and / or the second relay switch 201 are in the disconnected state, it means that the circuit loop is broken, so that the unit controller 20 cannot input the start signal to the frequency converter 30, so that the start signal of the frequency converter 30 is disconnected, the frequency converter 30 stops working, and the rotor stops rotating; the magnetic bearing controller 10 stops working after the set time, so that the rotor stops suspending, and the first relay switch 101 and / or the second relay switch 201 are disconnected to achieve the timely shutdown of the unit. In actual applications, the magnetic bearing controller 10 can start the timer when the frequency converter 30 stops working, and determine whether the set time has been reached through the timer.

[0030] It should be noted that the rotor here refers to the rotating component in the magnetic levitation centrifugal compressor, which is usually a rotating component used to compress gas. Magnetic levitation technology suspends the rotor in the air through a magnetic field, which can achieve higher efficiency and lower friction. Among them, the frequency converter 30 is used to control the rotation of the rotor, and the magnetic bearing controller 10 is used to control the suspension of the rotor. When the unit stops working, the rotor is usually stopped from rotating first, and when the rotor is in a stationary state, the rotor is stopped from suspending, so it is necessary to stop the frequency converter 30 first, and then stop the magnetic bearing controller 10 after a set period of time.

[0031] The set time refers to the time required for the rotor to change from the highest speed to the stationary state, that is, the magnetic bearing controller 10 needs to stop working when the rotor is in a stationary state. It can be understood that when the start signal of the inverter 30 is disconnected, causing the rotor to stop rotating, the magnetic bearing controller 10 may need a certain amount of time to gradually reduce the suspension accuracy so that the rotor stops smoothly. Therefore, the magnetic bearing controller 10 needs to stop working after the set time, so as to avoid the impact and damage to the unit caused by sudden stop, which helps to maintain the stability of the unit.

[0032] In this embodiment, a relay control logic is added to solve the problem of failure to shut down in time due to loss of connection with the unit.

[0033] In one embodiment, the shutdown control system 100 further includes a manual emergency stop switch 40, such as Figure 2 As shown, Figure 2 The schematic diagram of the shutdown control system 100 including the manual emergency stop switch 40 is shown. The first relay switch 101, the second relay switch 201 and the manual emergency stop switch 40 are connected in series to the frequency converter 30, and the specific connection is: the load output terminal KPS1-1 of the first relay switch 101 is connected in series with the load output terminal KPS2-1 of the second relay switch 201, the load output terminal KPS1-2 of the first relay switch 101 is connected to the output terminal VOUT of the transformer, and the load output terminal KPS2-2 of the second relay switch 201 and the manual emergency stop switch 40 are connected in series to the input terminal VIN of the frequency converter 30.

[0034] The on and off of the manual emergency stop switch 40 is controlled by the operator. When the manual emergency stop switch 40 is disconnected, the input circuit of the inverter 30 is disconnected, cutting off the start signal of the inverter 30, causing the inverter 30 to stop working, and the magnetic bearing controller 10 also stops working after a set time, thereby stopping the entire machine.

[0035] In this embodiment, in the case of configuring the first relay switch 101 and the second relay switch 201, an additional manual emergency stop switch 40 is configured, so that the first relay switch 101, the second relay switch 201 and the manual emergency stop switch 40 jointly control the unit to stop working. Among them, the first relay switch 101 and the second relay switch 201 control the unit to stop working according to the fault situation, and the manual emergency stop switch 40 is controlled by the operator to stop working in an emergency to prevent the occurrence or expansion of accidents.

[0036] In one embodiment, the first relay switch 101 and the second relay switch 201 can be closed in response to different signals. It is understandable that after the fault is repaired or when the whole machine is operating normally, the first relay switch 101 and the second relay switch 201 need to be in a closed state to transmit a start signal to the inverter 30 so that the inverter 30 can operate normally, and the magnetic bearing controller 10 also needs to operate normally, thereby ensuring the smooth operation of the magnetic suspension centrifugal compressor unit.

[0037] Based on this, the second relay switch 201 is further configured to close in response to a start signal received by the unit controller 20, wherein the start signal may be issued by the host computer when the magnetic levitation centrifugal compressor unit can operate normally.

[0038] The first relay switch 101 is configured to close in response to the suspension instruction received by the magnetic bearing controller 10 , indicating that the magnetic bearing controller 10 can operate normally.

[0039] In actual application, after the unit controller 20 receives the start signal, the unit controller 20 sends a suspension instruction to the magnetic suspension bearing controller 10. At this time, the magnetic suspension bearing controller 10 executes the rotor floating program after receiving the suspension instruction. When the magnetic suspension bearing controller 10 completes the rotor floating and the suspension is stable, the unit controller 20 sends a rotation instruction to the frequency converter 30, and the frequency converter 30 operates according to the rotation instruction so that the rotor can rotate. At this time, since the first relay switch 101 and the second relay switch 201 are both in the closed state, the frequency converter 30 can normally receive the start signal, thereby being able to execute the rotation instruction, so that all components of the magnetic suspension centrifugal compressor unit can be in a normal operating state.

[0040] In one embodiment, the first relay switch 101 and the second relay switch 201 are optocoupler relay switches. An optocoupler relay is a device that converts an input optical signal into an output electrical signal. Figure 1 and Figure 2 As shown, the optocoupler relay switch is usually composed of a light-emitting diode and a photosensitive diode, in which the light-emitting diode is also connected to a resistor. The resistor is connected here to limit the current to prevent the light-emitting diode from being overloaded and damaged. When the input signal is added to the light-emitting diode, the light-emitting diode emits a light signal, which will illuminate the photodetector, stimulate the photosensitive material in the photosensitive diode to generate charge, and cause current to flow, so that the photosensitive diode is in the on state, that is, the optocoupler relay is in the closed state. When there is no input signal on both sides of the light-emitting diode, no light signal is input to the photosensitive diode, causing the photosensitive diode to be in the off state and the optocoupler relay to be in the open state.

[0041] In one embodiment, the magnetic bearing controller 10 starts timing when a stop signal is detected, so that the magnetic bearing controller 10 can also stop working after a set time. When the magnetic bearing controller 10 receives the stop signal, the frequency converter 30 stops working, which is equivalent to starting timing when the magnetic bearing controller 10 stops working.

[0042] In one embodiment, the shutdown signal is triggered when the first relay switch 101 is disconnected, so that the magnetic bearing controller 10 can start timing when the first relay switch 101 is disconnected, and stop working after a set time. In this case, the magnetic bearing controller 10 can monitor the on-off state of the first relay switch 101. When the first relay switch 101 is detected to be disconnected, it indicates that there is a shutdown signal, thereby triggering the magnetic bearing controller 10 to start timing. Among them, the timing here is to determine whether the rotor has stopped rotating by the duration.

[0043] In one embodiment, the shutdown signal is triggered when the magnetic bearing controller 10 detects that the suspension accuracy of the rotor is less than a set value.

[0044] It is understandable that the relay switch is connected in series to the frequency converter 30. When any relay switch is disconnected, the start signal of the frequency converter 30 is disconnected and stops working. However, the magnetic bearing control cannot directly monitor the on-off state of the second relay switch 201 and the manual emergency stop switch 40, so that the magnetic bearing controller 10 cannot directly start timing according to the on-off state of the second relay switch 201 and the manual emergency stop switch 40.

[0045] In practical applications, stopping the frequency converter 30 will affect the suspension accuracy of the rotor monitored by the magnetic bearing controller 10. If the frequency converter 30 stops working, the balance of the electromagnetic force will be affected, thereby affecting the suspension accuracy of the rotor.

[0046] Based on this, the magnetic bearing controller 10 can monitor the suspension accuracy of the rotor. When the suspension accuracy is less than the set value, it indicates that there is a shutdown signal, and the frequency converter 30 stops working, and then starts timing. Among them, the timing here is used to determine the duration of the suspension accuracy less than the set value. If the timing duration reaches the set duration, it can be determined that the frequency converter 30 has stopped working and the rotor has stopped rotating, so that the magnetic bearing controller 10 also stops working.

[0047] In one embodiment, the shutdown control system 100 also includes an alarm module 50, which is respectively connected to the magnetic bearing controller 10 and the unit controller 20, and can monitor whether the magnetic bearing controller 10 and the unit controller 20 send out a fault signal. When it is detected that the magnetic bearing controller 10 sends out a first fault signal, or the unit controller 20 sends out a second fault signal, an alarm signal is sent out to remind the operator that a fault has occurred through the alarm signal.

[0048] Furthermore, the alarm module 50 sends out a first alarm signal when it detects a first fault signal, and sends out a second alarm signal when it detects a second fault signal, thereby being able to distinguish the sources of different fault signals through different alarm signals, allowing operators to locate and eliminate faults more quickly.

[0049] In one embodiment, the magnetic bearing controller 10 and the unit controller 20 communicate with each other to achieve fine adjustment and operation of the unit. The two controllers can use serial communication, which is a communication method for serial data transmission, and data exchange between devices can be achieved through a serial interface.

[0050] In the above embodiment, a relay switch is respectively provided in the magnetic bearing controller 10 and the unit controller 20, and the two relay switches are connected in series and connected to the frequency converter 30. When the magnetic bearing controller 10 and the frequency converter 30 fail, the frequency converter 30 and the magnetic bearing controller 10 will stop working simply by disconnecting the relay switch. Thus, on the basis of the original software control logic of the magnetic centrifugal compressor unit, a relay hardware control logic is added, and the unit can be shut down in time by hardware.

[0051] In one embodiment, Figure 3 As shown, Figure 3 It is a structural diagram of a magnetic levitation centrifugal compressor unit. The magnetic levitation centrifugal compressor unit includes a magnetic levitation centrifugal compressor 1, a condenser 2, an evaporator 3 and a shutdown control system 100 of the magnetic levitation centrifugal compressor unit. The shutdown control system 100 is composed of a magnetic levitation bearing controller 10, a unit controller 20 and a frequency converter 30. The magnetic levitation bearing controller 10 controls the suspension accuracy of the X and Y directions of the rotating shaft of the magnetic levitation centrifugal compressor, and the suspension accuracy of the axial Z direction translational freedom; the unit controller 20 controls the operating frequency of the magnetic levitation centrifugal compressor according to the collected unit information, and communicates with the magnetic levitation bearing controller 10 and the frequency converter 30 in a polling manner, and promptly receives the fault signals of the magnetic levitation bearing controller 10 and the frequency converter 30 to control the start and stop of the whole machine. The frequency converter 30 controls the axial Z direction rotational freedom.

[0052] The shutdown control system 100 will control the magnetic suspension centrifugal compressor unit to shut down in time by turning on and off the relay switch according to the above embodiment.

[0053] It should be understood that the various parts of the utility model can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiment, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0054] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0055] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0056] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A shutdown control system for a magnetically suspended centrifugal compressor unit, characterized in that: It comprises a magnetic bearing controller (10), a unit controller (20) and a frequency converter (30); The magnetic bearing controller (10) comprises a first relay switch (101); the first relay switch (101) is configured to be disconnected in response to a first fault signal sent by the magnetic bearing controller (10); the unit controller (20) comprises a second relay switch (201); the second relay switch (201) is configured to be disconnected in response to a second fault signal sent by the unit controller (20); The magnetic bearing controller (10) and the unit controller (20) are connected in series to the frequency converter (30) via a load output end of the first relay switch (101) and a load output end of the second relay switch (201); the frequency converter (30) stops working when the first relay switch (101) is disconnected or the second relay switch (201) is disconnected, and the magnetic bearing controller (10) stops working after a set time.

2. The shutdown control system according to claim 1, characterized in that: The shutdown control system (100) further comprises a manual emergency stop switch (40); a load output end of the first relay switch (101) and a load output end of the second relay switch (201) are connected in series to an output end of the frequency converter (30); and a load output end of the second relay switch and the manual emergency stop switch (40) are connected in series to an input end of the frequency converter (30); The frequency converter (30) stops working when the manual emergency stop switch (40) is disconnected, and the magnetic suspension bearing controller (10) stops working after a set time period.

3. The shutdown control system according to claim 1, characterized in that: The first relay switch (101) is further configured to close in response to a levitation signal received by the magnetic bearing controller (10); The second relay switch (201) is further configured to close in response to a start signal received by the unit controller (20).

4. The shutdown control system according to claim 1, characterized in that: The first relay switch (101) and the second relay switch (201) are optocoupler relay switches.

5. The shutdown control system according to claim 1 or 2, characterized in that: The magnetic bearing controller (10) starts timing when a shutdown signal is detected.

6. The shutdown control system according to claim 5, characterized in that: The shutdown signal is triggered when the first relay switch (101) is disconnected.

7. The shutdown control system according to claim 5, characterized in that: The shutdown signal is triggered when the magnetic bearing controller (10) detects that the suspension accuracy of the rotor is less than a set value.

8. The shutdown control system according to claim 1, characterized in that: The shutdown control system (100) further comprises an alarm module (50) respectively connected to the magnetic bearing controller (10) and the unit controller (20); the alarm module (50) sends an alarm signal when detecting the first fault signal or the second fault signal.

9. The shutdown control system according to claim 1, characterized in that: The magnetic bearing controller (10) and the unit controller (20) use serial communication as the communication method.

10. A magnetically suspended centrifugal compressor unit, characterized in that: include: A magnetically suspended centrifugal compressor (1), a condenser (2), an evaporator (3), and a shutdown control system (100) of a magnetically suspended centrifugal compressor unit as claimed in any one of claims 1 to 9.

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