Controller of magnetic suspension motor and extracorporeal membrane lung oxygenator

Abstract

The invention discloses a magnetic suspension motor controller and an extracorporeal membrane lung oxygenator, the magnetic suspension motor comprises a stator, a rotor, a torque winding, a suspension winding and a sensor, and the controller comprises a main control module which is electrically connected with the sensor and is used for obtaining target parameters of the rotor detected by the sensor, the target parameter comprises at least one of a current position and a current angle; the first driving circuit is electrically connected with the main control module and the torque winding and is used for outputting current to the torque winding under the control of the main control module; the second driving circuit is electrically connected with the main control module and the suspension winding and is used for outputting current to the suspension winding under the control of the main control module; the power supply module is used for supplying power to the first driving circuit, the second driving circuit and the main control module; wherein the main control module is used for controlling the output current of the first driving circuit and the second driving circuit according to target parameters collected by the sensor. According to the controller provided by the invention, the magnetic suspension motor can have rotation and suspension functions, and stable operation of the magnetic suspension motor can be ensured.

Description

Technical Field

[0001] The present application relates to the field of motor technology, and in particular to a controller of a magnetic levitation motor and an extracorporeal membrane oxygenator. Background Art

[0002] Extracorporeal membrane oxygenation (ECMO) is mainly used to provide continuous extracorporeal respiration and circulation to patients with severe cardiopulmonary failure to maintain their lives. Its power source is an external motor, which drives the impeller to maintain blood flow. Currently, most external motors use magnetic coupling motors, but there is a shaft in the pump head of the magnetic coupling motor. When running at high speed, the friction between the shaft and the shell may produce particles. In addition, the temperature of the friction part increases. These factors can easily lead to thrombosis.

[0003] In contrast, when the magnetic levitation motor is running, the impeller is suspended in the blood, and there is no frictional heating and no particles are generated. However, there is currently a defect that the magnetic levitation motor is unstable, and the controller that controls the magnetic levitation motor needs to be improved. Summary of the invention

[0004] The present application provides a controller of a magnetic levitation motor and an extracorporeal membrane oxygenator, which can ensure the stable operation of the magnetic levitation motor.

[0005] According to a first aspect of an embodiment of the present application, there is provided a controller for a magnetic levitation motor, wherein the magnetic levitation motor comprises a stator, a rotor, a torque winding, a suspension winding and a sensor, and the controller comprises: a main control module, electrically connected to the sensor, and used to obtain target parameters of the rotor detected by the sensor, wherein the target parameters include at least one of a current position and a current angle; a first drive circuit, electrically connected to the main control module and the torque winding, and used to output current to the torque winding under the control of the main control module; a second drive circuit, electrically connected to the main control module and the suspension winding, and used to output current to the suspension winding under the control of the main control module; a power supply module, used to supply power to the first drive circuit, the second drive circuit and the main control module; wherein the main control module is used to control the output current of the first drive circuit and the second drive circuit according to the target parameters collected by the sensor.

[0006] A second aspect of an embodiment of the present application provides an extracorporeal membrane oxygenator, comprising: a magnetic levitation motor, the magnetic levitation motor comprising a stator, a rotor, a torque winding, a suspension winding and a sensor, the sensor being used to detect a target parameter of the rotor, the target parameter comprising at least one of a current position and a current angle; and a controller of any of the above items.

[0007] The beneficial effect is: in the controller of the present application, the main control module controls the current of the torque winding through the first drive circuit and controls the current of the suspension winding through the second drive circuit. The first drive circuit and the second drive circuit are independent of each other and do not affect each other, which can ensure the circuit safety performance and avoid damage to one of the first drive circuit and the second drive circuit due to the influence of the other. At the same time, the controller of the present application can also enable the magnetic levitation motor to rotate and suspend in five degrees of freedom, thereby ensuring the stability of the operation of the magnetic levitation motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0009] Figure 1 It is a schematic diagram of the structure of the controller, the magnetic levitation motor and the host computer in one embodiment of the present application;

[0010] Figure 2 yes Figure 1 A schematic diagram of the arrangement of the sensor in one embodiment;

[0011] Figure 3 It is a structural schematic diagram of a controller, a magnetic levitation motor and a host computer in another embodiment of the present application;

[0012] Figure 4 yes Figure 3 A schematic diagram of the structure of the first drive circuit, the first sampling circuit and the torque winding in one embodiment;

[0013] Figure 5 yes Figure 3 A schematic structural diagram of the first drive circuit, the first sampling circuit and the torque winding in another embodiment;

[0014] Figure 6 yes Figure 3 A schematic structural diagram of the first drive circuit, the first sampling circuit and the torque winding in another embodiment;

[0015] Figure 7 yes Figure 3 A schematic structural diagram of the first drive circuit, the first sampling circuit and the torque winding in another embodiment. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0017] It should be noted that the terms "first" and "second" in this application are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0018] Before introducing the solution of this application, a brief introduction to the magnetic levitation motor is given:

[0019] In a magnetic levitation motor, the rotor is suspended by the force of a magnetic field so that there is no mechanical contact between the rotor and the stator. Therefore, the magnetic levitation motor has the characteristics of high cleanliness, no precipitation, no particles, no dynamic seal, and excellent performance. It has good application prospects in ultra-pure drive fields such as biochemistry, medical treatment, and semiconductor manufacturing. Specifically, a magnetic levitation motor is a motor that integrates the functions of rotation and suspension. On the winding that generates the rotating drive magnetic field (hereinafter defined as the "torque winding"), another set of windings (hereinafter defined as the "suspension winding") is wound to generate an excitation magnetic field. The interaction between the two magnetic fields breaks the balanced distribution of the original drive magnetic field, thereby generating a radial force acting on the rotor and achieving the suspension of the rotor.

[0020] See also Figure 1 In one embodiment of the present application, the controller is used to control a magnetic levitation motor, which includes a stator (not shown) and a rotor (not shown) rotating relative to the stator. The magnetic levitation motor also includes a torque winding 10, a suspension winding 20 and a sensor 30. The magnetic field generated by the torque winding 10 after inputting current is used to realize rotor rotation, and the magnetic field generated by the suspension winding 20 after inputting current is used to realize rotor suspension. The controller includes a main control module 110, a first drive circuit 130, a second drive circuit 140 and a power module 150.

[0021] The main control module 110 is the core module in the controller, which is used to coordinate the cooperation between various modules in the controller. The main control module 110 is electrically connected to the sensor 30, and the sensor 30 is used to detect the target parameters of the rotor, and the target parameters include at least one of the current position and the current angle. In one embodiment, the sensor 30 is specifically used to detect the current position and the current angle of the rotor. In one embodiment, depending on the rotor material and the design details of the magnetic levitation motor, the sensor 30 can be a Hall sensor, or an eddy current sensor, or a combination of different types of sensors, that is, the sensor 30 includes at least one of a Hall sensor and an eddy current sensor. These sensors can reflect the current position (distance from the boundary) and the current rotation angle of the rotor at any time by sensing physical quantities such as magnetic fields and currents. In a specific embodiment, the sensor 30 is a Hall sensor, and specifically a linear Hall sensor, such as Figure 2 As shown, in a specific example, the number of sensors 30 is multiple ( Figure 2 6 are used as an illustration), multiple sensors 30 are evenly distributed in the circumferential direction of the rotor, and multiple sensors 30 are symmetrically distributed about the center of the rotor. At this time, two sensors 30 symmetrical about the center of the rotor are connected into a straight line, and the two sensors 30 can reflect the offset position of the rotor relative to the straight line. At the same time, the sine curves measured by the multiple sensors 30 can obtain the current angle of the rotor. It should be noted that the present application does not impose specific restrictions on the type and number of sensors 30, as long as the sensor 30 can detect at least one of the current position and current angle of the rotor.

[0022] The first drive circuit 130 is electrically connected to the main control module 110 and the torque winding 10, and is used to output current to the torque winding 10 under the control of the main control module 110. Specifically, the main control module 110 controls whether to output current to the torque winding 10 and controls the magnitude of the current output to the torque winding 10 through the first drive circuit 130. In other words, the magnitude of the output current of the first drive circuit 130 is controlled by the main control module 110.

[0023] The second drive circuit 140 is electrically connected to the main control module 110 and the suspension winding 20, and is used to output current to the suspension winding 20 under the control of the main control module 110. Specifically, the main control module 110 controls whether to output current to the suspension winding 20 and the magnitude of the current output by the suspension winding 20 through the second drive circuit 140. In other words, the magnitude of the output current of the second drive circuit 140 is controlled by the main control module 110.

[0024] The power module 150 is used to supply power to the first driving circuit 130 , the second driving circuit 140 and the main control module 110 , and is the energy source in the controller.

[0025] The main control module 110 is used to control the output current of the first drive circuit 130 and the second drive circuit 140 according to the target parameters collected by the sensor 30. Specifically, the main control module 110 controls the output current of the first drive circuit 130 according to the target parameters collected by the sensor 30, so that the torque winding 10 generates a magnetic field to achieve the rotation of the rotor, and the main control module 110 controls the output current of the second drive circuit 140 according to the target parameters collected by the sensor 30, so that the suspension winding 20 generates a magnetic field to achieve the suspension of the rotor.

[0026] It can be seen from the above content that the main control module 110 controls the current of the torque winding 10 through the first drive circuit 130 and controls the current of the suspension winding 20 through the second drive circuit 140. The first drive circuit 130 and the second drive circuit 140 are independent of each other and do not affect each other, which can ensure the circuit safety performance and avoid damage to one of the first drive circuit 130 and the second drive circuit 140 due to the influence of the other. At the same time, the controller of the present application can also enable the magnetic levitation motor to rotate and suspend in five degrees of freedom, thereby ensuring the stability of the operation of the magnetic levitation motor.

[0027] Continue reading Figure 1 The controller also includes a signal conditioning module 121, which is electrically connected to the main control module 110 and the sensor 30. The signal output by the sensor 30 is output to the main control module 110 after being conditioned by the signal conditioning module 121, wherein the signal conditioning by the signal conditioning module 121 includes at least one of amplifying the signal and filtering the signal. The signal conditioning module 121 can remove the noise component in the output signal of the sensor 30 or amplify the useful component in the signal, which can improve the accuracy of the subsequent signal processing by the main control module 110. It should be noted that the signal conditioning module 121 may not be provided in other embodiments.

[0028] See also Figure 3 The first drive circuit 130 is specifically a three-phase inverter current, which is used to convert the current input by the power module 150 into three-phase electricity and provide it to the torque winding 10, and the second drive circuit 140 is also specifically a three-phase inverter current, which is used to convert the current input by the power module 150 into three-phase electricity and provide it to the suspension winding 20. The structures of the first drive circuit 130 and the second drive circuit 140 can be the same or different.

[0029] The first drive circuit 130 is a full-bridge inverter circuit or an H-bridge inverter circuit, and the second drive circuit 140 can also be a full-bridge inverter circuit or an H-bridge inverter circuit. The present application does not limit the specific structures of the first drive circuit 130 and the second drive circuit 140.

[0030] Continue reading Figure 3The controller also includes a first sampling circuit 160 and a second sampling circuit 170 .

[0031] The first sampling circuit 160 is electrically connected to the first drive circuit 130 and the main control module 110, and the first sampling circuit 160 is used to sample the output current of the first drive circuit 130; the second sampling circuit 170 is electrically connected to the second drive circuit 140 and the main control module 110, and the second sampling circuit 170 is used to sample the output current of the second drive circuit 140; wherein the main control module 110 is specifically used to: control the output current of the first drive circuit 130 according to the target parameters collected by the sensor 30 and the current sampled by the first sampling circuit 160, and control the output current of the second drive circuit 140 according to the target parameters collected by the sensor 30 and the current sampled by the second sampling circuit 170.

[0032] Specifically, the main control module 110 uses a decoupling algorithm and a field-oriented control (FOC) algorithm to accurately control the current of the torque winding 10 according to the target parameters of the rotor and the output current of the first drive circuit 130 to ensure the rotation function of the rotor; and the main control module 110 uses a decoupling algorithm and a field-oriented control (FOC) algorithm to accurately control the current of the suspension winding 20 according to the target parameters of the rotor and the output current of the second drive circuit 140 to achieve suspension of the rotor.

[0033] The structures of the first sampling circuit 160 and the second sampling circuit 170 may be the same or different.

[0034] According to different current sampling principles, the first sampling circuit 160 may use a Hall current sensor to sample the output current of the first drive circuit 130 , or the first sampling circuit 160 may also use a resistor in series to sample the output current of the first drive circuit 130 .

[0035] When the first driving circuit 130 is an inverter circuit, the first sampling circuit 160 is a three-resistance sampling circuit, a dual-resistance sampling circuit or a single-resistance sampling circuit. Figure 4 When the first sampling circuit 160 is a three-resistance sampling circuit, the first sampling circuit 160 includes three sampling resistors 161. At this time, the currents of the three lower bridge arms in the first driving circuit 130 are respectively obtained through the three sampling resistors 161 to obtain valid data; see Figure 5 When the first sampling circuit 160 is a dual-resistance sampling circuit, the first sampling circuit 160 includes two sampling resistors 161. At this time, the currents of any two lower bridge arms in the first driving circuit 130 are respectively obtained through the two sampling resistors 161 to obtain valid data; see Figure 6When the first sampling circuit 160 is a single resistor sampling circuit, the first sampling circuit 160 includes a sampling resistor 161, and the sampling resistor 161 is connected in series to the DC bus for sampling.

[0036] Among them, combined Figure 4 as well as Figure 7 When the first sampling circuit 160 is a three-resistance sampling circuit, according to the different positions of the sampling resistor 161, the first sampling circuit 160 can be a low-end sampling circuit (such as Figure 4 As shown), it can also be a high-end sampling circuit (such as Figure 7 ), where continued reference Figure 4 as well as Figure 7 Compared with the low-end sampling circuit, when the first sampling circuit 160 is a high-end sampling circuit, since the sampling resistor 161 directly samples the output current of the bridge arm of the first drive circuit 130, the current value sampled by the first sampling circuit 160 is the real output current of the first drive circuit 130, so there is no need to use an algorithm to reconstruct and calculate the current sampled by the first sampling circuit 160, which is easy to use, simple and efficient. Similarly, when the first sampling circuit 160 is a dual-resistance sampling circuit, the first sampling circuit 160 can also be a low-end sampling circuit or a high-end sampling circuit, which will not be described in detail here. In short, the present application does not limit the specific structure of the first sampling circuit 160 and the second sampling circuit 170, as long as the first sampling circuit 160 can sample the output current of the first drive circuit 130 and the second sampling circuit 170 can sample the output current of the second drive circuit 140.

[0037] Continue reading Figure 3 The controller also includes a first protection circuit 180 and a second protection circuit 190 .

[0038] The first protection circuit 180 is electrically connected to the first drive circuit 130, the first sampling circuit 160, and the main control module 110, and is used for the first protection circuit 180 to cut off the output of the first drive circuit 130 when the current collected by the first sampling circuit 160 is greater than the first current threshold. Specifically, when the current collected by the first sampling circuit 160 is greater than the first current threshold, it indicates that the first drive circuit 130 may be abnormal. Therefore, in order to protect the circuit and the torque winding 10, the first protection circuit 180 cuts off the output of the first drive circuit 130 to prevent accidents. At the same time, the protection status of the first protection circuit 180 on the first drive circuit 130 will also be sent to the main control module 110, so that the main control module 110 can perform data analysis afterwards.

[0039] Similarly, the second protection circuit 190 is electrically connected to the second drive circuit 140, the second sampling circuit 170, and the main control module 110, and is used for the second protection circuit 190 to cut off the output of the second drive circuit 140 when the current collected by the second sampling circuit 170 is greater than the second current threshold. Specifically, when the current collected by the second sampling circuit 170 is greater than the second current threshold, it indicates that the second drive circuit 140 may be abnormal, so in order to protect the circuit and the suspension winding 20, the second protection circuit 190 cuts off the output of the second drive circuit 140 to prevent accidents. At the same time, the protection status of the second protection circuit 190 on the second drive circuit 140 will also be sent to the main control module 110, so that the main control module 110 can perform data analysis afterwards.

[0040] The first current threshold and the second current threshold may be equal or different, and may be set according to actual conditions. Meanwhile, the structures of the first protection circuit 180 and the second protection circuit 190 may be the same or different, and are not limited here.

[0041] Continue reading Figure 3 The controller further includes a communication module 200, which is electrically connected to the main control module 110 and is used to communicate with the host computer 210. Specifically, the main control module 110 can send the operating state of the magnetic levitation motor (such as the current position of the rotor, the current rotation angle light) to the host computer 210, and the host computer 210 can also control the magnetic levitation motor through the communication module 200, such as adjusting the speed of the magnetic levitation motor. Among them, the power module 150 also supplies power to the communication module 200.

[0042] The communication module 200 may specifically be a wireless Bluetooth module or a WiFi communication module, etc. The present application does not limit the specific type of the communication module 200.

[0043] The present application also protects an extracorporeal membrane oxygenator, which includes a magnetic levitation motor and a controller. The controller has the same structure as the controller in any of the above embodiments. The specific structure of the magnetic levitation motor and the controller can be found in the above related content and will not be repeated here.

[0044] It should be noted that the magnetic levitation motor and controller of the present application can be applied not only to extracorporeal membrane oxygenator, but also to other devices, without limitation herein.

[0045] The above description is only an embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A controller for a magnetic levitation motor, characterized in that: The magnetic levitation motor includes a stator, a rotor, a torque winding, a suspension winding and a sensor, and the controller includes: a main control module, electrically connected to the sensor, and used to obtain a target parameter of the rotor detected by the sensor, wherein the target parameter includes at least one of a current position and a current angle; a first drive circuit, electrically connected to the main control module and the torque winding, and configured to output current to the torque winding under the control of the main control module; a second driving circuit, electrically connected to the main control module and the suspension winding, and configured to output current to the suspension winding under the control of the main control module; A power supply module, used to supply power to the first drive circuit, the second drive circuit and the main control module; Wherein, the main control module is used to control the output current of the first drive circuit and the second drive circuit according to the target parameter collected by the sensor.

2. The controller according to claim 1, characterized in that: The controller further comprises: A first sampling circuit, electrically connected to the first driving circuit and the main control module, the first sampling circuit being used to sample an output current of the first driving circuit; A second sampling circuit, electrically connected to the second driving circuit and the main control module, the second sampling circuit being used to sample an output current of the second driving circuit; Among them, the main control module is specifically used to: control the output current of the first drive circuit according to the target parameter collected by the sensor and the current sampled by the first sampling circuit, and control the output current of the second drive circuit according to the target parameter collected by the sensor and the current sampled by the second sampling circuit.

3. The controller according to claim 2, characterized in that: The first driving circuit is an inverter circuit, and the first sampling circuit is a three-resistance sampling circuit, a dual-resistance sampling circuit or a single-resistance sampling circuit; When the first sampling circuit is a three-resistor current sampling circuit or a dual-resistor sampling circuit, the first sampling circuit is a low-end sampling circuit or a high-end sampling circuit.

4. The controller according to claim 2, characterized in that: The controller further comprises: a first protection circuit, electrically connected to the first drive circuit, the first sampling circuit, and the main control module, and configured to cut off the output of the first drive circuit when the current sampled by the first sampling circuit is greater than a first current threshold; The second protection circuit is electrically connected to the second driving circuit, the second sampling circuit, and the main control module, and is used to cut off the output of the second driving circuit when the current sampled by the second sampling circuit is greater than a second current threshold.

5. The controller according to claim 1, characterized in that: The first drive circuit is a full-bridge inverter circuit or an H-bridge inverter circuit, and the second drive circuit is a full-bridge inverter circuit or an H-bridge inverter circuit.

6. The controller according to claim 1, characterized in that: The controller further comprises: The signal conditioning module is electrically connected to the sensor and the main control module, and is used for conditioning the signal output by the sensor and outputting it to the main control module, wherein the conditioning includes at least one of amplification processing and filtering processing.

7. The controller according to claim 1, characterized in that: The controller further comprises: The communication module is electrically connected to the main control module and is used for communicating with the host computer.

8. An extracorporeal membrane oxygenator, characterized in that: include: A magnetic levitation motor, the magnetic levitation motor comprising a stator, a rotor, a torque winding, a suspension winding and a sensor, the sensor being used to detect a target parameter of the rotor, the target parameter comprising at least one of a current position and a current angle; A controller as claimed in any one of claims 1 to 7.

9. The extracorporeal membrane oxygenator according to claim 8, characterized in that: The sensor includes at least one of a Hall sensor and an eddy current sensor.

10. The extracorporeal membrane oxygenator according to claim 9, characterized in that: The sensor is a Hall sensor, and there are multiple sensors, the multiple sensors are evenly distributed in the circumferential direction of the rotor, and the multiple sensors are symmetrically arranged about the center of the rotor.

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