Magnetic suspension generator set, fault shutdown control method, electronic equipment and medium

Abstract

The invention discloses a magnetic suspension generator set, a fault shutdown control method, electronic equipment and a medium, the generator set comprises an evaporator, a magnetic suspension expansion generator, a condenser and a working medium pump which are connected in sequence, the working medium pump provides power for circulating conveying of a working medium, and a bypass pipeline is arranged at the working medium outlet end of the evaporator; the bypass pipeline is communicated with a working medium inlet of the condenser, redundant working media directly skip the magnetic suspension expansion generator to be fed into the condenser, and control valves are arranged on the bypass pipeline and between the evaporator and a connecting pipeline of the magnetic suspension expansion generator. And a working medium inlet of the evaporator is communicated with a cooling flow channel arranged at a protection bearing of the magnetic suspension expansion generator through a pipeline. The fault shutdown control method disclosed by the invention can provide effective protection for the magnetic suspension expansion generator in the field of industrial low-temperature waste heat utilization; impeller overspeed is eradicated from a control method, protection on a rotor protection bearing is enhanced, and the service life of equipment is greatly prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of operation control of a magnetic levitation generator set, and in particular to a magnetic levitation generator set, a fault shutdown control method, electronic equipment and a medium. Background Art

[0002] Magnetic levitation units are widely used in energy-saving transformation projects in various industries to replace the original screw machines, such as magnetic levitation blowers, magnetic levitation air compressors, and magnetic levitation refrigeration compressors, due to their advantages such as oil-free lubrication system, clean working fluid, friction-free bearings, high system efficiency, and low vibration. In recent years, in response to "carbon neutrality", the industrial waste heat recovery power generation industry has become increasingly popular, and magnetic levitation expansion generators have also been gradually used in organic Rankine cycle generator sets.

[0003] The rotor speed of a conventional asynchronous generator is usually 3000r / min, while the rotor speed of a magnetic expansion generator is very high, usually between 18000 and 24000r / min. Therefore, the impact of a sudden drop of the rotor at high speed on the bearing and the prevention of impeller overspeeding that is mechanically connected to the motor need to be paid special attention to. Relying on the advantages of magnetic levitation motors, magnetic expansion generators account for an increasingly high proportion of organic Rankine cycle generator sets. However, there are no clear specifications in the existing technical data for the shutdown priority strategy of this type of equipment. For the above reasons, magnetic expansion generator sets lack effective protection during operation, which can easily cause damage to motor components and affect the service life of the equipment. Summary of the invention

[0004] Technical purpose: In view of the shortcomings of existing magnetic levitation generator sets, the present invention discloses a magnetic levitation generator set, a fault shutdown control method, an electronic device and a medium.

[0005] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution: A magnetic levitation generator set generates electricity based on an organic Rankine cycle power generation technology, comprising an evaporator, a magnetic levitation expansion generator, a condenser and a working fluid pump which are sequentially connected to form a working fluid circulation loop, the working fluid pump provides power for circulating the working fluid, a bypass pipeline is arranged at the working fluid outlet end of the evaporator, the bypass pipeline is connected with the working fluid inlet of the condenser, and the excess working fluid is directly sent to the condenser by skipping the magnetic levitation expansion generator, a control valve is arranged on the bypass pipeline and between the connecting pipelines of the evaporator and the magnetic levitation expansion generator; the working fluid inlet of the evaporator is connected with a cooling flow channel arranged at a protective bearing of the magnetic levitation expansion generator through a pipeline, and the flow of the working fluid is controlled by an electromagnetic valve arranged on the pipeline.

[0006] Preferably, the control valve of the present invention includes a bypass valve arranged on the bypass pipeline and an intake valve arranged on the pipeline connecting the evaporator and the magnetic levitation expansion generator. Both the intake valve and the bypass valve are pneumatic valves, the intake valve is a normally closed valve, and the bypass valve is a normally open valve.

[0007] Preferably, the control system of the magnetic levitation expansion generator of the present invention includes a magnetic bearing controller system and a PLC controller system, and the magnetic bearing controller system and the PLC controller system are both electrically connected to a rectifier inverter unit for controlling the stator magnetic field of the magnetic levitation expansion generator; the magnetic bearing controller system provides a start signal for the inverter, and the PLC controller system provides a frequency signal of the magnetic field, and the rotation control of the magnetic levitation expansion generator is performed collaboratively by the magnetic bearing controller system and the PLC controller system.

[0008] Preferably, the magnetic bearing controller system and the PLC controller system of the present invention are connected to a UPS power supply, and the UPS power supply is used to temporarily power the magnetic bearing controller system and the PLC controller system when the working power supply is cut off, so as to perform shutdown operation.

[0009] The present invention discloses a fault shutdown control method for the magnetic levitation generator set according to the above-mentioned method. The shutdown fault type is preset. When a shutdown fault occurs in the magnetic levitation generator set, the air intake valve is switched to a normally closed state, the bypass valve is switched to a normally open state, and the working gas of the magnetic levitation expansion generator is stopped from entering. The control system of the magnetic levitation expansion generator detects the magnetic levitation state of the rotor and sends a control signal to perform shutdown control.

[0010] Preferably, when the rotor of the magnetic levitation expansion generator of the present invention cannot maintain a suspended state, the rotor falls into the protective bearing for friction deceleration, the solenoid valve opens, and the working fluid is sprayed onto the protective bearing through the cooling channel of the protective bearing for lubrication and cooling.

[0011] Preferably, the preset shutdown fault types of the present invention include air compressor supply failure, power supply failure, rectifier unit failure, inverter unit failure, magnetic bearing controller system failure, PLC control and active shutdown failure, wherein the active shutdown failure is triggered by the emergency stop button preset by the magnetic levitation expansion generator.

[0012] Preferably, in each shutdown fault type, when the air intake valve is closed to cut off the air intake, the suspension state of the rotor is synchronously detected, and when the rotor remains suspended, a given speed is controlled by a PLC controller system to perform a free stop, and the PLC controller system operates through the power provided by a connected power supply or a UPS power supply in the event of a power failure; when the rotor cannot remain suspended, the protective bearing is used to decelerate and shut down the rotor.

[0013] The present invention discloses an electronic device, including a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the program, the above-mentioned method for controlling the failure shutdown of a magnetic levitation generator set is implemented. The memory can be various types of memory, such as random access memory, read-only memory, flash memory, etc. The processor can be various types of processors, such as a central processing unit, a microprocessor, a digital signal processor or an image processor, etc.

[0014] The present invention discloses a computer-readable storage medium storing computer-executable instructions. The computer-executable instructions are used for the above-mentioned fault shutdown control method of a magnetic levitation generator set. The storage medium includes: a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk or an optical disk, etc., which can store program codes.

[0015] Beneficial effects: The magnetic levitation generator set, fault shutdown control method, electronic equipment and medium of the present invention have the following beneficial effects: 1. The present invention sets control valves at the bypass pipeline and the working medium inlet of the magnetic levitation expansion generator, which can timely control the speed of the magnetic levitation expansion generator to avoid the impeller overspeeding when the generator is stopped freely due to high-pressure gas. The cooling flow channel at the protective bearing can lubricate and cool the protective bearing when the rotor cannot be suspended and the protective bearing is used for friction deceleration, thereby protecting the motor structure and extending the life of the equipment. The cooling medium uses the original medium of the magnetic levitation expansion generator set, which will not increase additional costs and can be recycled.

[0016] 2. The bypass valve and the air intake valve of the present invention both adopt pneumatic valves, and the air intake valve adopts a normally closed valve, and the bypass valve adopts a normally open valve. When a fault occurs in the generator set, the two valves can automatically restore to a fully closed or open state. Compared with the solenoid valve, the opening and closing time of the valve is short, and it is not affected by power failure, and the structural reliability is high.

[0017] 3. The present invention simultaneously controls the rotation of the magnetic levitation expansion generator through the magnetic bearing controller system and the PLC controller system, which is conducive to timely shutdown in the event of a fault, avoiding the problem of the motor being unable to stop due to failure of a single controller, and improving the safety of the generator set operation.

[0018] 4. The present invention is provided with a UPS power supply, which can supply power to the control system when a power failure occurs, thereby ensuring that the system has sufficient time to perform corresponding shutdown operations, avoiding the situation in which the magnetic bearing controller cannot maintain normal suspension of the rotor and the PLC controller cannot issue a command in time to open the bypass valve and close the intake valve, causing the impeller to run away, thereby further strengthening the operation protection of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0020] Figure 1 This is a structural diagram of the magnetic levitation generator set of the present invention; Figure 2 This is a shutdown control flow chart when an active shutdown failure and an air compressor air supply failure occur in the present invention; Figure 3 This is a flow chart of shutdown control when power failure occurs in the present invention; Figure 4 The present invention is a flow chart of the magnetic suspension expansion motor startup control; Among them, 1-evaporator, 2-magnetic levitation expansion generator, 3-condenser, 4-working fluid pump, 5-bypass pipeline, 6-solenoid valve, 7-bypass valve, 8-intake valve. DETAILED DESCRIPTION

[0021] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are set forth herein below. Each embodiment and example is provided by way of explanation of the apparatus, composition and materials of the present disclosure, rather than limitation. On the contrary, the following description provides a convenient illustration of an exemplary embodiment for implementing the present disclosure. In fact, it will be clear to those skilled in the art that various modifications and variations may be made in the teachings of the present disclosure without departing from the scope or spirit of the present disclosure.

[0022] like Figure 1 As shown, the present invention discloses a magnetic levitation generator set, which generates electricity based on the organic Rankine cycle power generation technology, including an evaporator 1, a magnetic levitation expansion generator 2, a condenser 3 and a working fluid pump 4 which are sequentially connected to form a working fluid circulation loop, and the working fluid pump 4 provides power for circulating the working fluid, and a bypass pipeline 5 is arranged at the working fluid outlet end of the evaporator 1, and the bypass pipeline 5 is connected with the working fluid inlet of the condenser 3, and the excess working fluid is directly skipped over the magnetic levitation expansion generator 2 and sent into the condenser 3, and control valves are arranged on the bypass pipeline 5 and between the connecting pipelines of the evaporator 1 and the magnetic levitation expansion generator 2; the working fluid inlet of the evaporator 1 is connected with the cooling flow channel arranged at the protective bearing of the magnetic levitation expansion generator 2 through a pipeline, and the flow of the working fluid is controlled by an electromagnetic valve 6 arranged on the pipeline.

[0023] When the generator set is running, the working fluid enters the magnetic levitation expansion generator 2 from the evaporator to perform work and generate electricity. When the unit fails and needs to be shut down, it is necessary to cut off the working fluid entry channel first, which is achieved through the corresponding control valve. In an embodiment of the present invention, the control valve includes a bypass valve 7 arranged on the bypass pipeline 5 and an intake valve 8 arranged on the pipeline connecting the evaporator 1 and the magnetic levitation expansion generator 2. The intake valve 8 and the bypass valve 7 are both pneumatic valves. The intake valve 8 is a normally closed valve and the bypass valve 7 is a normally open valve. Compared with electric valves, pneumatic valves have high reliability, fast action, and can quickly switch states. At the same time, the present invention selects corresponding normally closed valves and normally open valves according to the valve setting position, which can automatically reset when power is lost, thereby improving structural reliability. In a fault state, it ensures shutdown safety and avoids impeller runaway.

[0024] The control system of the magnetic levitation expansion generator of the present invention comprises a magnetic bearing controller system and a PLC controller system, wherein the magnetic bearing controller system and the PLC controller system are both electrically connected to a rectifier inverter unit for controlling the stator magnetic field of the magnetic levitation expansion generator; the magnetic bearing controller system provides a start signal of the inverter, and the PLC controller system provides a frequency signal of the magnetic field, and the rotation control of the magnetic levitation expansion generator is performed in coordination with the magnetic bearing controller system and the PLC controller system, such as Figure 4 As shown, the motor will only run when the PLC controller and the magnetic bearing controller give corresponding start signals at the same time. Even if one of the controllers fails, it can be shut down in time to improve the safety of the entire system. In addition, the magnetic bearing controller system and the PLC controller system of the present invention are connected to a UPS power supply. When the working power supply is cut off, the UPS power supply is used to temporarily power the magnetic bearing controller system and the PLC controller system, so that the control system can continue to run and perform shutdown operations.

[0025] The present invention discloses a fault shutdown control method according to the above-mentioned magnetic levitation generator set. The shutdown fault type is preset first. When a situation in the shutdown fault type occurs, a shutdown operation is performed. It should be noted that the shutdown control shutdown of the shutdown fault type of the present invention is the highest priority shutdown strategy that affects the safe operation of the generator. The shutdown control of other fault types can be directly operated by relying on the control system. When a shutdown fault occurs in the magnetic levitation generator set, the intake valve is switched to a normally closed state, the bypass valve is switched to a normally open state, and the working gas of the magnetic levitation expansion generator is stopped from entering. The control system of the magnetic levitation expansion generator detects the magnetic levitation state of the rotor and sends a control signal to perform shutdown control. In the shutdown end state, the bypass valve needs to be kept open, the intake valve needs to be closed, the given speed of the PLC controller system is 0, and the start signal of the magnetic bearing controller system is in the False state.

[0026] The preset shutdown fault types include air compressor supply failure, power supply failure, rectifier unit failure, inverter unit failure, magnetic bearing controller system failure, PLC control and active shutdown failure. The active shutdown failure is triggered by the emergency stop button preset on the magnetic levitation expansion generator and controlled by the operator to facilitate human intervention.

[0027] In the present invention, in each shutdown fault type, when the air intake valve is closed to cut off the air intake, the suspension state of the rotor needs to be detected synchronously. When the rotor remains suspended, the given speed is controlled by the PLC controller system to perform free parking. The PLC controller system operates through the power provided by the connected power supply or the UPS power supply when the power supply fails. When the rotor cannot remain suspended, the protective bearing is used to decelerate the rotor and shut it down. At this time, the rotor falls into the protective bearing for friction deceleration, the solenoid valve is opened, and the working fluid is sprayed on the protective bearing through the cooling flow channel of the protective bearing to lubricate and cool it, thereby reducing the friction between the protective bearing and the rotor, reducing the temperature of the protective bearing surface, and thus increasing the service life of the protective bearing.

[0028] like Figure 2 As shown, when the generator set needs to shut down due to an emergency, that is, when an active shutdown fault occurs, the operator presses the emergency stop button, and the control system sends a signal to the air compressor to control the air path of the intake valve and the bypass valve, so that the intake valve is closed and the bypass valve is opened to cut off the working medium intake; then the magnetic levitation expansion motor is shut down according to the suspension state of the rotor. For the monitoring of the suspension state of the rotor, the displacement sensor can be used to directly monitor the displacement state of the rotor.

[0029] When the rotor can be suspended, the PLC controller system gives a speed control signal to control the rotor to gradually reduce the speed until it stops; when the rotor cannot maintain the suspended state, it will fall into the protective bearing. Since the rotor is still in a high-speed rotation state when it stops, there will be greater friction with the protective bearing during the initial time, thereby generating high temperature on the contact surface. It is necessary to open the solenoid valve and provide working fluid delivery power through the working fluid pump to send the working fluid into the protective bearing for cooling and lubrication to reduce damage to the rotor and protective bearing and extend the service life of the protective bearing. The cooling time can be set according to the operating speed of the rotor and other conditions. After the rotor is stationary for a certain period of time, the given speed of the PLC controller system is reset to zero, and the startup signal status of the magnetic bearing controller system is False, so that the equipment can be restarted later.

[0030] When there is a failure in the air supply of the air compressor, the compressed air pressure supplied to the control valve will be insufficient or even no compressed air will be available. The control contacts of the corresponding control valve will be disconnected, allowing the control valve to automatically restore to the corresponding normally open or normally closed state, the intake valve will be closed, and the bypass valve will be opened to cut off the intake of the working medium. The speed will then be given through the PLC control system to control the rotation of the rotor and achieve free parking until the speed returns to zero, completing the shutdown operation.

[0031] When a power failure occurs, such as a mains trip or a main incoming line failure, the generator set enters isolated grid operation. At this time, the DC bus voltage in the rectifier inverter unit requires the activation of the braking resistor to release the energy instantly to reduce the voltage. Otherwise, the rectifier inverter unit will damage the device due to high voltage. The execution action of the control valve is the same as when the air compressor fails to supply air, cutting off the air intake of the magnetic levitation expansion generator. The UPS power supply starts to supply power to the PLC controller system and the magnetic bearing controller system, allowing them to continue working, and perform rotor speed control to stop the operation. When the rotor speed returns to zero, the parking is completed.

[0032] When the rectifier unit fails, the situation is similar to the power failure, and the corresponding parking control process is the same, and the braking resistor needs to be enabled for parking control. When the inverter unit fails and the bearing controller system fails, the execution action of the control valve is the same as when the air compressor fails, cutting off the air intake of the magnetic suspension expansion generator, and performing the parking control of the generator through the PLC controller system, and determining whether the solenoid valve is open according to the suspension state of the rotor.

[0033] The fault shutdown control method of the present invention can provide effective protection for the magnetic levitation expansion generator in the field of industrial low-temperature waste heat utilization, prevent impeller overspeed and strengthen the protection of the rotor protection bearing from the control method, and greatly extend the service life of the equipment.

[0034] The present invention also discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the above-mentioned method for controlling the failure shutdown of a magnetic levitation generator set is implemented. The memory may be various types of memory, such as a random access memory, a read-only memory, a flash memory, etc. The processor may be various types of processors, such as a central processing unit, a microprocessor, a digital signal processor, or an image processor, etc.

[0035] The present invention also discloses a computer-readable storage medium storing computer-executable instructions, which are used for the fault shutdown control method of the above-mentioned magnetic levitation generator set. The storage medium includes: a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk or an optical disk, and other media that can store program codes.

Claims

1. A magnetic levitation generator set, which generates electricity based on organic Rankine cycle power generation technology, characterized in that: The invention comprises an evaporator (1), a magnetic levitation expansion generator (2), a condenser (3) and a working fluid pump (4) which are connected in sequence to form a working fluid circulation loop. The working fluid pump (4) provides power for circulating the working fluid. A bypass pipeline (5) is arranged at the working fluid outlet of the evaporator (1). The bypass pipeline (5) is connected to the working fluid inlet of the condenser (3) so that excess working fluid is directly sent to the condenser (3) by skipping the magnetic levitation expansion generator (2). Control valves are arranged on the bypass pipeline (5) and between the connecting pipelines of the evaporator (1) and the magnetic levitation expansion generator (2). The working fluid inlet of the evaporator (1) is connected to a cooling flow channel arranged at a protective bearing of the magnetic levitation expansion generator (2) through a pipeline, and the flow of the working fluid is controlled by an electromagnetic valve (6) arranged on the pipeline.

2. A magnetic levitation generator set according to claim 1, characterized in that: The control valve comprises a bypass valve (7) arranged on the bypass pipeline (5) and an air intake valve (8) arranged on the pipeline connecting the evaporator (1) and the magnetic suspension expansion generator (2); the air intake valve (8) and the bypass valve (7) are both pneumatic valves; the air intake valve (8) is a normally closed valve, and the bypass valve (7) is a normally open valve.

3. A magnetic levitation generator set according to claim 1, characterized in that: The control system of the magnetic levitation expansion generator includes a magnetic bearing controller system and a PLC controller system, and the magnetic bearing controller system and the PLC controller system are both electrically connected to a rectifier inverter unit for controlling the stator magnetic field of the magnetic levitation expansion generator; the magnetic bearing controller system provides a start signal of the inverter, and the PLC controller system provides a frequency signal of the magnetic field, and the rotation control of the magnetic levitation expansion generator is performed in coordination with the magnetic bearing controller system and the PLC controller system.

4. A magnetic levitation generator set according to claim 3, characterized in that: The magnetic bearing controller system and the PLC controller system are connected to a UPS power supply, and the UPS power supply is used to temporarily power the magnetic bearing controller system and the PLC controller system when the working power supply is cut off, so as to perform a shutdown operation.

5. A fault shutdown control method for a magnetic levitation generator set according to any one of claims 1 to 4, characterized in that: The shutdown fault type is preset. When a shutdown fault occurs in the magnetic levitation generator set, the intake valve switches to the normally closed state, the bypass valve switches to the normally open state, and the working gas of the magnetic levitation expansion generator is stopped from entering. The control system of the magnetic levitation expansion generator detects the magnetic levitation state of the rotor and sends a control signal for shutdown control.

6. A fault shutdown control method for a magnetic levitation generator set according to claim 5, characterized in that: When the rotor of the magnetic levitation expansion generator cannot maintain the suspended state, the rotor falls into the protective bearing for friction deceleration, the solenoid valve opens, and the working fluid is sprayed onto the protective bearing through the cooling flow channel of the protective bearing for lubrication and cooling.

7. A fault shutdown control method for a magnetic levitation generator set according to claim 5, characterized in that: The preset shutdown fault types include air compressor supply failure, power supply failure, rectifier unit failure, inverter unit failure, magnetic bearing controller system failure, PLC control and active shutdown failure, among which the active shutdown failure is triggered by the emergency stop button preset on the magnetic levitation expansion generator.

8. A fault shutdown control method for a magnetic levitation generator set according to claim 7, characterized in that: In each shutdown fault type, when the air intake valve is closed to cut off the air intake, the suspension state of the rotor is detected synchronously. When the rotor remains suspended, the given speed is controlled by the PLC controller system to perform a free stop. The PLC controller system runs on the power provided by the connected power supply or the UPS power supply in the event of a power failure. When the rotor cannot remain suspended, the protective bearing is used to decelerate the rotor and stop it.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the fault shutdown control method of a magnetic levitation generator set described in any one of claims 5-8 is implemented.

10. A computer-readable storage medium storing computer-executable instructions, characterized in that: The computer executable instructions are used to execute the fault shutdown control method of a magnetic levitation generator set as described in any one of claims 5-8.

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