Activation method and device of ventricular assist device

Abstract

This application discloses a method and apparatus for starting a ventricular assist device. The method includes: at a first moment, applying a first current to a first stator and a second stator to align the zero-point lines of the stator and rotor; at a second moment, stopping the application of the first current to the second stator and applying a second current to the first stator to suspend the rotor; after suspending the rotor to a first position, applying a third current to the second stator to control the rotor to rotate at a target speed at the first position. This application uses two stators: the first stator controls the rotor to suspend at the first position, and the second stator controls the rotor to rotate at the first position. This suspends the rotor before rotation, avoiding frictional resistance when the impeller slides relative to the housing, thereby reducing thrombus formation caused by surface damage to the inner wall of the impeller and housing, and improving user safety.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a method and apparatus for activating a ventricular assist device. Background Technology

[0002] Pumps used as mechanical circulation support devices include pumping mechanisms for pumping fluid from one location to another, such as centrifugal pumps, axial flow pumps, or magnetic levitation pumps for pumping blood from the heart to other parts of the body. These pumps achieve the function of pumping fluid by including an impeller disposed within the pump housing to push the fluid through the pump housing from the inlet end to the outlet end of the pump.

[0003] When the operation of the ventricular assist device or impeller is interrupted, it is desirable to effectively start or resume pump operation to achieve fluid pumping. However, starting the impeller can be difficult, especially when the impeller is magnetically attached to the pump housing. Summary of the Invention

[0004] This application provides a method and apparatus for starting a ventricular assist device, which can reduce the friction between the impeller and the housing when the impeller starts to rotate, and avoid fluid embolism or condensation caused by damage to the inner wall surface of the housing assembly and the impeller due to friction.

[0005] In a first aspect, embodiments of this application provide a method for starting a ventricular assist device. The ventricular assist device includes a housing, an impeller disposed within the housing, and a motor for driving the impeller to rotate in a suspended manner. The motor includes a rotor fixedly connected to the impeller and a stator for driving the rotor to rotate in a suspended manner. The stator includes a first stator and a second stator. The method includes:

[0006] At the first moment, a first current is applied to the first stator and the second stator to make the zero line of the stator coincide with that of the rotor;

[0007] At the second moment, the first current is stopped being applied to the second stator, and the second current is applied to the first stator to suspend the rotor;

[0008] After suspending the rotor to the first position, a third current is applied to the second stator to control the rotor to rotate at the first position.

[0009] Secondly, an embodiment of this application provides a control unit for a ventricular assist device. The ventricular assist device includes a housing, an impeller disposed within the housing, and a motor for driving the impeller to rotate in a suspended manner. The motor includes a rotor fixedly connected to the impeller and a stator for driving the rotor to rotate in a suspended manner. The stator includes a first stator and a second stator. The control unit includes one or more processors, which are used for:

[0010] At the first moment, a first current is applied to the first stator and the second stator to make the zero line of the stator coincide with that of the rotor;

[0011] At the second moment, the first current is stopped being applied to the second stator, and the second current is applied to the first stator to suspend the rotor;

[0012] After suspending the rotor to the first position, a third current is applied to the second stator to control the rotor to rotate at the first position.

[0013] Thirdly, embodiments of this application provide a ventricular assist device, characterized in that the ventricular assist device comprises:

[0014] case;

[0015] An impeller disposed within the housing;

[0016] A motor that drives the impeller to rotate in a suspended manner, the motor including a rotor fixedly connected to the impeller and a stator that drives the rotor to rotate in a suspended manner, the stator including a first stator and a second stator;

[0017] The control unit connected to the motor is used to perform some or all of the steps described in the method described in the first aspect above.

[0018] Fourthly, embodiments of this application provide a medical device, the medical device including a processor, a memory, a communication interface, and one or more programs, the one or more programs being stored in the memory and configured to be executed by the processor, the programs including instructions for performing some or all of the steps described in the method described in the first aspect above.

[0019] Fifthly, embodiments of this application provide a computer-readable storage medium storing a computer program for electronic data interchange, wherein the computer program causes a computer to perform some or all of the steps described in the method described in the first aspect above.

[0020] Sixthly, embodiments of this application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, the computer program being operable to cause a computer to perform some or all of the steps described in the method described in the first aspect of embodiments of this application. The computer program product may be a software installation package.

[0021] The technical solution provided in this application involves applying a first current to the first and second stators at a first moment, aligning the zero-point lines of the stators and rotor; at a second moment, stopping the application of the first current to the second stator and applying a second current to the first stator to suspend the rotor; after suspending the rotor to the first position, applying a third current to the second stator to control the rotor to rotate at the target speed from the first position. This application uses two stators: the first stator controls the rotor to suspend at the first position, and the second stator controls the rotor to rotate at the first position. This suspends the rotor before rotating, avoiding frictional resistance when the impeller slides relative to the casing, thereby reducing surface damage to the inner wall of the impeller and casing that could lead to thrombus formation and improving user safety. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of a ventricular assist device provided in an embodiment of this application;

[0024] Figure 2 This is a partial explosion diagram of a ventricular assist device provided in an embodiment of this application;

[0025] Figure 3 This is a schematic flowchart of a method for starting a ventricular assist device provided in an embodiment of this application;

[0026] Figure 4 This is a schematic diagram of a rotor zero-point line provided in an embodiment of this application;

[0027] Figure 5 This is a schematic diagram of a stator zero-point line provided in an embodiment of this application;

[0028] Figure 6 This is a schematic diagram showing the stator zero line coinciding with the rotor zero line in an embodiment of this application;

[0029] Figure 7 This is a schematic diagram of the positions of the rotor and stator at time T1 provided by an embodiment of this application;

[0030] Figure 8 This is a schematic diagram of the positions of the rotor and stator at time T2 provided by an embodiment of this application;

[0031] Figure 9 This application provides a top view of the positions of the rotor and stator at time T2.

[0032] Figure 10 This is a schematic diagram of the positions of the rotor and stator at time T3 provided in an embodiment of this application;

[0033] Figure 11 This application provides a top view of the positions of the rotor and stator at time T3 according to an embodiment of the present application;

[0034] Figure 12 This is a schematic diagram of the positions of the rotor and stator at time T4 provided by an embodiment of this application;

[0035] Figure 13 This application provides a top view of the rotor and stator positions at time T4 according to an embodiment of the present application;

[0036] Figure 14 This is a schematic diagram of the positions of the rotor and stator at time T5 provided in an embodiment of this application;

[0037] Figure 15 This application provides a top view of the rotor and stator positions at time T5 according to an embodiment of the present application;

[0038] Figure 16 This is a schematic diagram of the positions of the rotor and stator at time T6 provided in an embodiment of this application;

[0039] Figure 17 This application provides a top view of the rotor and stator positions at time T6 according to an embodiment of the present application;

[0040] Figure 18 This is a schematic diagram of the positions of the rotor and stator at time T7 provided by an embodiment of this application;

[0041] Figure 19 This application provides a top view of the rotor and stator positions at time T7 according to an embodiment of the present application;

[0042] Figure 20 This is a schematic diagram of the structure of a medical device provided in an embodiment of this application. Detailed Implementation

[0043] To help those skilled in the art better understand the technical solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the description of the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0044] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, software, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but also includes steps or units not listed, or other steps or units inherent to such processes, methods, products, or apparatus.

[0045] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0046] The pump involved in this application can be a ventricular assist device in medical assistive devices, which can be an implantable ventricular assist device (VAD) that can be attached to the left ventricle, the right ventricle, or both ventricles of the heart. The VAD can further include a magnetically levitated pump capable of delivering the entire output to the left ventricle based on pulmonary or blood circulation.

[0047] This application describes the embodiments using a centrifugal magnetic levitation pump as an example.

[0048] A ventricular assist device can be attached to the heart via a ventricular connection assembly (such as a top ring, ventricular cuff, or ventricular band). This ventricular connection assembly can be sutured to the heart and attached to the ventricular assist device. The other end of the ventricular assist device can be connected to the ascending aorta via an outlet tube and / or an artificial blood vessel connected to the outlet tube. This allows the ventricular assist device to effectively transfer blood from the weakened ventricle and propel it into the aorta, thereby circulating it to the rest of the patient's vascular system and providing ventricular assist function.

[0049] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of a ventricular assist device 100 provided in an embodiment of this application, and particularly relates to a centrifugal magnetic levitation ventricular assist device. The ventricular assist device 100 includes a housing assembly, an impeller 20 disposed within the housing assembly, and a motor 10 that drives the impeller 20 to levitate and rotate.

[0050] The housing assembly has a liquid inlet 14, a liquid outlet 15, and a first chamber 30 and a second chamber 40 spaced apart. Both the liquid inlet 14 and the liquid outlet 15 communicate with the first chamber 30. In the illustrated embodiment, the central axis of the liquid inlet 14 and the central axis of the liquid outlet 15 are perpendicular; the first chamber 30 and the second chamber 40 are arranged along the central axis of the liquid inlet 14. The first chamber 30 has a first chamber wall 31 and a second chamber wall 32 spaced apart and opposite to each other along the central axis of the liquid inlet 14. The second chamber 40 is disposed close to the second chamber wall 32.

[0051] The impeller 20 is rotatably disposed within the first chamber 30. The impeller 20 is located between the first chamber wall 31 and the second chamber wall 32. Specifically, during smooth operation of the impeller 20, its rotation axis 21 coincides with the central axis of the inlet 14. The rotation of the impeller 20 allows external liquid (e.g., blood) to enter the first chamber 30 from the inlet 14 and flow out from the outlet 15.

[0052] The motor 10 includes a stator 11 and a rotor 13. The stator 11 is disposed within the second chamber 40, and the rotor 13 is disposed within the first chamber 30. The rotor 13 is fixedly connected to the impeller 20. The stator 11 can drive the rotor 13 to levitate and rotate, and the impeller 20 can levitate and rotate with the rotor 13. Specifically, the rotor 13 is disposed within the impeller 20. The levitating rotation of the impeller 20 means that the impeller 20 does not contact the cavity wall of the first chamber 30 during rotation.

[0053] For example, the motor 10 may be a three-phase brushless direct current motor (BLDC), with the stator 11 having three windings controlled by different corresponding phases U, V, and W of the power input controlled by the three-phase motor. The motor 10 may also include an inverter circuit that can be used to convert the DC input into a three-phase output. For example, the ventricular assist device 100 may receive a three-phase AC input.

[0054] exist Figure 2 In the illustrated embodiment, the stator 11 includes a first stator 110 and a second stator 120, both of which are generally annular. The first stator 110 includes 3N first winding units, which are equally spaced along a first circle. The second stator 120 includes 3N second winding units, which are equally spaced along a second circle. The second circle and the first circle are concentric, and the diameter of the first circle is smaller than the diameter of the second circle. In other words, the first stator 110 and the second stator 120 are coaxially arranged, and the first stator 110 is located inside the second stator 120. Specifically, each first winding unit and each second winding unit includes stator teeth and stator coils disposed on the stator teeth.

[0055] Rotor 13 includes a first rotor 130 and a second rotor 140, both of which are fixedly connected to the impeller 20. Specifically, both the first rotor 130 and the second rotor 140 are disposed within the impeller 20. Both the first rotor 130 and the second rotor 140 are annular in shape, and are concentric and coaxially arranged, with their central axes coinciding with the rotation axis 21 of the impeller 20. The inner diameter of the second rotor 140 is larger than the outer diameter of the first rotor 130. Along the central axis of either the first rotor 130 or the second rotor 140, the position of the first rotor 130 corresponds to the position of the first stator 110 (i.e., the first rotor 130 and the first stator 110 are aligned along the axial direction of the first stator 110). The first stator 110 can drive the first rotor 130 to rotate and levitate, meaning the first stator 110 and the first rotor 130 together constitute the first motor. The position of the second stator 120 corresponds to the position of the second rotor 140 (i.e., the second rotor 140 and the second stator 120 are aligned along the axial direction of the second stator 120). The second stator 120 can drive the second rotor 140 to rotate and levitate, meaning the second stator 120 and the second rotor 140 together constitute the second motor. The first motor and the second motor can be controlled independently. In some embodiments, the first motor is used to drive the impeller 20 to levitate and / or rotate, and the second motor is also used to drive the impeller 20 to levitate and / or rotate. For example, the first motor is used to drive the impeller 20 to levitate, and the second motor is used to drive the impeller 20 to rotate. For example, the functions of the first motor and the second motor can be switched. At certain times, the first motor drives the impeller 20 to levitate, and the second motor drives the impeller 20 to rotate; at other times, the first motor drives the impeller to rotate, and the second motor drives the impeller to levitate. Since both the first rotor 130 and the second rotor 140 are fixed to the impeller 20, the first rotor 130, the second rotor 140, and the impeller 20 move synchronously. The magnetic pole distribution angles, stator core, and coil distribution angles of the first motor and the second motor are all consistent to achieve synchronous control of the first motor and the second motor.

[0056] In the illustrated embodiment, the outer peripheral wall of the first rotor 130 is fixedly connected to the inner peripheral wall of the second rotor 140 to reduce the magnetic pole angle deviation of the impeller 20. For example, the first rotor 130 and the second rotor 140 can be fixedly connected by adhesive bonding. In other embodiments, the outer peripheral wall of the first rotor 130 and the inner peripheral wall of the second rotor 140 are opposite to each other and spaced apart. The outer peripheral wall of the first rotor 130 is the side wall of the first rotor 130 that faces away from its central axis; the inner peripheral wall of the second rotor 140 is the side wall of the second rotor 140 that faces its central axis.

[0057] Specifically, both the first rotor 130 and the second rotor 140 include multiple magnetic blocks. The multiple magnetic blocks of the first rotor 130 are assembled into a first circular ring structure, and the multiple magnetic blocks of the second rotor 140 are assembled into a second circular ring structure. Each magnetic block is approximately fan-shaped. In some embodiments, the magnetization direction of each magnetic block of the first rotor 130 is the same as the axial direction of the first rotor 130, and the magnetic poles of adjacent magnetic blocks are opposite. In some embodiments, the multiple magnetic blocks of the first rotor 130 are arranged in a Hellbeck array manner, that is, the first rotor 130 is a Hellbeck array magnet. The arrangement of the magnetic blocks in the second rotor 140 is roughly the same as that in the first rotor 130, and will not be described again.

[0058] In some embodiments, the positions of multiple magnetic blocks of the first rotor 130 are respectively arranged in a one-to-one correspondence with the positions of multiple magnetic blocks of the second rotor 140, that is, each magnetic block of the first rotor 130 corresponds to the position of one magnetic block of the second rotor 140, so as to form multiple magnetic block groups with corresponding positions. In each magnetic block group with corresponding positions, the magnetic blocks of the first rotor 130 and the magnetic blocks of the second rotor 140 have the same magnetization direction. The magnetic blocks of the first rotor 130 and the magnetic blocks of the second rotor 140 are arranged radially along the first rotor 130 and / or the second rotor 140, and the outer peripheral wall of the magnetic block of the first rotor 130 is opposite to the inner peripheral wall of the magnetic block of the second rotor 140. In each magnetic block group with corresponding positions, the central angle corresponding to the sector ring where the magnetic block of the first rotor 130 is located is equal to the central angle corresponding to the sector ring where the magnetic block of the second rotor 140 is located. In some embodiments, in each group of magnetic blocks at each position, the outer peripheral wall of the magnetic block of the first rotor 130 is fixedly connected to or in contact with the inner peripheral wall of the magnetic block of the second rotor 140, that is, the outer peripheral wall of the first rotor 130 and the outer peripheral wall of the second rotor 140 are fixedly connected to or in contact. In some embodiments, in each group of magnetic blocks at each position, the magnetic blocks of the first rotor 130 and the magnetic blocks of the second rotor 140 are arranged radially spaced apart along the second rotor 140. The outer peripheral wall of the magnetic block of the first rotor 130 is the sidewall of the magnetic block facing away from the central axis of the first rotor 130; the inner peripheral wall of the magnetic block of the second rotor 140 is the sidewall of the magnetic block facing the central axis of the second rotor 140.

[0059] In this configuration, each magnetic block of the first rotor 130 has a center line that is perpendicular to and intersects the central axis of the first rotor 130; each magnetic block of the second rotor 140 also has a center line that is perpendicular to and intersects the central axis of the second rotor 140. In each group of magnetic blocks at each position, the center lines of the magnetic blocks of the first rotor 130 and the center lines of the magnetic blocks of the second rotor 140 coincide.

[0060] In some embodiments, the first stator 110 and the second stator 120 may also share a single rotor 13. That is, along the central axis of the rotor 13, the position of the rotor 13 corresponds to both the first stator 110 and the second stator 120. Specifically, the rotor 13 is aligned axially with both the first stator 110 and the second stator 120. In this case, the rotor 130 has a large radial width. The first stator 110 can drive the rotor 13 to levitate and rotate, and the second stator 140 can also drive the rotor 13 to levitate and rotate. The first stator 110 and the second stator 120 are independently controlled. In this case, the rotor 13 includes multiple magnetic blocks, which are assembled into a ring structure. At least some of the magnetic blocks are magnetized along the axial direction of the rotor 13; and along the circumference of the rotor 13, the magnetic poles of adjacent axially magnetized magnetic blocks are opposite. In some embodiments, the magnetization direction of each magnet of rotor 13 is the same as the axial direction of rotor 13, and the magnetic poles of adjacent magnets are opposite; in some embodiments, the plurality of magnets of rotor 13 are arranged in a Halebeck array manner, that is, rotor 13 is a Halebeck array magnet. Each magnet in rotor 13 has a center line, and the center line is perpendicular to and intersects the central axis of rotor 130.

[0061] The impeller 20 moves axially relative to the housing assembly along the rotation axis 21. During rotation, the impeller 20 is suspended within the housing assembly by a contactless bearing, such as a magnetic bearing, which creates a magnetic levitation system. For example, in some embodiments, magnets (not shown) are also provided in both the housing assembly and the impeller 20. These magnets together form a magnetic bearing, which exerts a force on the impeller 20. This force, combined with the magnetic force between the stator 11 and the rotor 13, acts on the impeller 20, causing it to levitate in the first chamber 30 in a magnetically balanced state, thus achieving the levitated rotational motion of the impeller 20. The control unit 33 controls the levitation attitude and position of the impeller 20 by controlling the magnetic force between the stator 11 and the rotor 13. Simultaneously, a torsional force is generated in the direction perpendicular to the rotation axis 21 by the attractive and repulsive forces between the stator 11 and the rotor 13, causing the impeller 20 to rotate in that direction. When the impeller 20 rotates at a preset speed, the attraction or thrust between the stator 11 and the rotor 13 causes the impeller 20 in the first chamber 30 to suspend and rotate within the chamber 10.

[0062] The ventricular assist device 100 also includes a control unit 33 and a sensor 50. The control unit 33 is electrically connected to the stator 11, and the sensor 50 is electrically connected to the control unit 33. The sensor 50 is used to detect the magnetic pole angle and levitation height of the impeller 20. The control unit 33 is used to receive the detection results from the sensor 50 and can control the rotational speed and levitation height of the impeller 20 via the motor 10 according to the detection results. Specifically, the levitation height of the impeller 20 is the distance of the impeller 20 relative to the second cavity wall 32.

[0063] Furthermore, the control unit 33 is used to monitor and control the start-up and subsequent operation of the motor 10, including performing three-phase field-oriented control (FOC) methods. The control unit 33 can be a module independent of the stator 11 or integrated within the stator 11. The control unit 33 includes hardware and software for controlling various aspects of the operation of the motor 10. The control unit 33 can be coupled to the motor 10 via an interface to collect at least one piece of data from the motor 10. This at least one piece of data may include measured current flowing through the stator 11, data measured by sensor 50, motor speed, pressure difference across the pump, flow pulsation, fluid velocity, etc.

[0064] The sensor 50 includes 3N first position sensors 51 and 3N second position sensors 52. Each first position sensor 51 is disposed between two adjacent first winding units and is used to measure the levitation height and magnetic pole angle of the first rotor 130 corresponding to the first winding unit. Each second position sensor 52 is disposed between two adjacent second winding units and is used to measure the levitation height and magnetic pole angle of the second rotor 140 corresponding to the second winding unit. Specifically, each position sensor is positioned relative to the rotor 13 on the impeller 20 via a path. As the impeller 20 rotates, causing the S and N poles of the rotor 13 to alternately pass near the position sensor, the signal level of the position sensor, representing the magnetic flux intensity, changes in an up-and-down wave pattern (such as a square wave or a sine wave). Therefore, by detecting the time change of the output signal of the position sensor, the positional relationship of the first rotor 130 relative to the first stator 110 and the positional relationship of the second rotor 140 relative to the second stator 120 can be detected, thereby calculating the rotational speed and levitation height of the impeller 20.

[0065] For example, the first position sensor 51 and the second position sensor 52 can be Hall sensors, eddy current sensors, distance sensors, etc.

[0066] The first stator 110 and the second stator 120 are approximately circular. Every three adjacent first winding units 110 of the 3N first winding units 110 form a first three-phase winding, and every three adjacent first winding units 120 of the 3N second winding units 120 form a second three-phase winding. The positions of the first three-phase windings correspond one-to-one with the positions of the second three-phase windings. For example, the U phase of the first three-phase winding unit is aligned with the U phase of the second three-phase winding unit along the radial direction of the first stator 110 and / or the second stator 120; the V phase of the first three-phase winding unit is aligned with the V phase of the second three-phase winding unit along the radial direction of the first stator 110 and / or the second stator 120; and the W phase of the first three-phase winding unit is aligned with the W phase of the second three-phase winding unit along the radial direction of the first stator 110 and / or the second stator 120. For example, the first rotor 130 and the second rotor 140 are both fixedly connected to the impeller 20, so that the first rotor 130, the second rotor 140 and the impeller 20 move synchronously. The control unit 33 can control the magnetic pole angle and levitation height of the entire rotor 13 by controlling the magnitude and phase of the current flowing through the stator coil of the first winding unit 110 and / or the second winding unit 120; and, by controlling the levitation height of the rotor 13, the control unit 33 makes the impeller 20 levitate relative to the stator 11 at the desired axial position.

[0067] The winding units in the first three-phase winding and the second three-phase winding are three windings controlled by different corresponding phases U, V, and W of the voltage input controlled by the three-phase motor. The control unit 33 can control the application of current to the first three-phase winding to control the levitation and / or rotation of the first rotor 130, thereby controlling the levitation and / or rotation of the impeller 20. The control unit 33 can also control the application of current to the second three-phase winding to control the levitation and / or rotation of the second rotor 140, thereby controlling the levitation and / or rotation of the impeller 20.

[0068] Based on the above description, this application will now be described from the perspective of method examples.

[0069] Please see Figure 3 , Figure 3 This application provides a schematic flowchart of a method for starting a ventricular assist device, applicable to, for example... Figures 1-2 The ventricular assist device 100 is shown. (As shown in the image) Figure 3 As shown, the method includes the following steps.

[0070] S310. At the first moment, a first current is applied to the first stator and the second stator to make the zero line of the stator coincide with that of the rotor.

[0071] When the ventricular assist device 100 is not in operation, the impeller 20 will be held against the second cavity wall 32 by the attraction between the stator 11 and the rotor 13. At this time, the suspension height of the impeller 20 relative to the second cavity wall 32 is 0, that is, the impeller 20 is in contact with the second cavity wall 32. In this case, when the ventricular assist device 100 responds to the user's operation to start the impeller 20 to rotate, the contact between the impeller 20 and the cavity wall in the first cavity 30 will cause the relative sliding friction resistance between the impeller 20 and the housing assembly to increase, causing surface damage to the impeller 20 and the inner wall of the housing assembly, which may easily lead to fluid retention or thrombosis.

[0072] Therefore, when the application receives a start command to start the impeller 20 to rotate, the control unit 33 can first control the rotor 13 to suspend so that the impeller 20 is separated from the second cavity wall 32 or in a non-contact state, thereby avoiding thrombosis caused by surface damage to the impeller 20 and the second cavity wall 32 due to friction between the impeller 20 and the second cavity wall 32.

[0073] When the ventricular assist device 100 is stationary (not in operation), since no current is applied to the stator coil in the stator 11, the coincidence of the zero line of the stator 11 and the zero line of the rotor 13 is unknown. That is, the winding unit in the rotor 13 and the stator 11 are not directly opposite each other, so there is no current in the stator coil in the stator 11 and it cannot generate an effective axial magnetic force with the rotor 13.

[0074] In this application, before suspending the rotor 13, the control unit 33 first controls the rotor 13 to move along the circumferential direction of the rotor 13 so that the zero line of the stator 11 coincides with the zero line of the rotor 13, so that the rotor 13 can be suspended and rotated subsequently. When the rotor 13 includes multiple magnetic blocks, the zero line of the rotor 13 is the center line of any magnetic block. When the rotor 13 includes a first rotor 130 and a second rotor 140, the zero line of the rotor 13 is the center line of the magnetic block of the first rotor 130 and / or the center line of the magnetic block of the second rotor 140 in any corresponding magnetic block group (since the center lines of the magnetic blocks of the first rotor 130 and the second rotor 140 in the corresponding magnetic block group coincide, the zero line of the rotor 13 is also the center line of the magnetic block of the first rotor 130 and / or the center line of the magnetic block of the second rotor 140 in the corresponding magnetic block group).

[0075] Optionally, applying a first current to the first stator and the second stator to make the zero line of the stator coincide with that of the rotor includes: applying the first current to the first phase winding unit in the first three-phase winding and the second three-phase winding respectively, so that the projection of the center line of the first phase winding unit in the first three-phase winding, the projection of the center line of the first phase winding unit in the second three-phase winding coincides with the projection of the zero line of the rotor on a target plane, wherein the zero line is the center line of any magnetic block group or magnetic block in the rotor, and the target plane is a plane perpendicular to the central axis of the first stator and / or the second stator.

[0076] For example, such as Figure 4 As shown, rotor 13 includes a first rotor 130 and a second rotor 140. Both the first rotor 130 and the second rotor 140 include 8 magnetic blocks. Rotor 13 rotates counterclockwise at a speed w. The zero-point line O of rotor 13 is the center line of the magnetic block group corresponding to any position of the magnetic pole N on the side of the first rotor 130 and the second rotor 140 closest to stator 11. Figure 5 As shown, both the first stator 110 and the second stator 120 include six winding units. Three adjacent U-phase winding units, V-phase winding units, and W-phase winding units in the first stator 110 form the first three-phase winding. Three adjacent U-phase winding units, V-phase winding units, and W-phase winding units in the second stator 120 form the second three-phase winding. The zero-point line P of the stator 11 is the center line of the U-phase winding unit in both the first and second three-phase windings; that is, the first-phase winding unit is the U-phase winding unit. The center line of any winding unit in the first stator 110 and the second stator 120 is perpendicular to and intersects the central axis of the stator 11.

[0077] It should be noted that the zero-point line O of rotor 13 can also be the center line of the magnetic block group with any magnetic pole as the S pole on the side closest to stator 11 in the first rotor 130 and the second rotor 140. The zero-point line P of stator 11 can also be the center line of the V-phase winding unit or the W-phase winding unit in the first and second three-phase windings, that is, the first phase winding unit can be either the V-phase winding unit or the W-phase winding unit.

[0078] Upon receiving the start command, the control unit 33 applies current to the U-phase winding units of the first and second three-phase windings at the first instant. This causes the U-phase winding units in the first and second three-phase windings to exhibit S-pole magnetism, generating a magnetic attraction force with the N-pole magnetic blocks of the rotor 13. This magnetic attraction force moves the rotor 13 along its circumference, causing the projection of the zero-point line P of the stator 11 to coincide with the projection of the zero-point line O of the rotor 13 on the target plane. In other words, the projection of the center line of the magnetic block group or block with N-pole magnetism near the stator 11 in the rotor 13 coincides with the projection of the center lines of the U-phase winding units of the first and second three-phase windings on the target plane. This target plane is a plane perpendicular to the central axis of the first stator 110 and / or the second stator 120, for example, a plane parallel to the second cavity wall 32 or a plane parallel to the side of the impeller 20 near the stator 11.

[0079] For example, the projection of the zero-point line P of stator 11 and the projection of the zero-point line O of rotor 13 coincide on the target plane as follows: Figure 6 As shown, sensor 50 can mark this position as the zero point, which is the initial zero point position of rotor 13. Subsequently, control unit 33 can calculate the current rotational speed of rotor 13 based on the positional change of rotor 13 relative to stator 11.

[0080] S320, at the second moment, stop applying the first current to the second stator and apply the second current to the first stator to suspend the rotor.

[0081] After aligning the projection of the zero-point line O of rotor 13 with the projection of the zero-point line P of stator 11 on the target plane and determining the initial zero-point position of rotor 13, control unit 33 can then levitate and rotate rotor 13. The first stator 110 controls the levitation and rotation of the first rotor 130, and the second stator 120 controls the levitation and rotation of the second rotor 140. During the startup process of motor 10, the first stator 110 can be used to control the levitation of rotor 13, and the second stator 120 can control the rotation of rotor 13; alternatively, the first stator 110 can be used to control the rotation of rotor 13, and the second stator 120 can be used to control the levitation of rotor 13. This embodiment uses the first stator 110 controlling the levitation of rotor 13 and the second stator 120 controlling the rotation of rotor 13 for illustration.

[0082] At the second moment, the control unit 33 controls the rotor 13 to levitate, so that the impeller 20 is separated from the second cavity wall 32 or in a non-contact state. Specifically, after the projection of the zero line O of the rotor 13 and the projection of the zero line P of the stator 11 coincide on the target plane, the control unit 33 stops supplying current to the second stator 120, that is, stops applying the first current to the U-phase winding unit of the second three-phase winding, and simultaneously applies the second current to the first stator 110, so that the rotor 13 can levitate.

[0083] Since the rotor 13 is at its initial zero position, the U-phase winding unit of the first three-phase winding is directly opposite the N-pole magnetic block in the first rotor 130. To levitate the rotor 13, the control unit 33 can change the direction of the current flowing to the first stator 110 (i.e., change the direction of the current applied to the U-phase winding unit of the first three-phase winding), causing the U-phase winding unit of the first three-phase winding to exhibit a change in magnetic polarity from S-pole to N-pole. The U-phase winding unit of the first three-phase winding with N-pole magnetic polarity generates an axial magnetic thrust with the N-pole magnetic block in the first rotor 130. This axial magnetic thrust causes the impeller 20 to move axially, thereby achieving levitation control of the impeller 20.

[0084] The direction of the second current is opposite to that of the first current, and the magnitude of the second current can gradually increase, thereby increasing the suspension height of the impeller 20 relative to the second cavity wall 32. In other words, the second current is a straight line rising in the opposite direction to the first current.

[0085] S330. After suspending the rotor to the first position, a third current is applied to the second stator to control the rotor to rotate at the first position.

[0086] In this application, if the impeller 20 comes into contact with the housing assembly during rotation, the rotation of the impeller 20 will increase the relative sliding friction resistance between the impeller 20 and the housing assembly, thereby causing surface damage to the inner wall of the impeller 20 and the housing assembly, resulting in fluid retention or thrombosis. To avoid this problem, during the rotation of the impeller 20, the control unit 33 should try to control the impeller 20 to rotate in a suspended position near the center of the first chamber 30, or control the axial movement range of the rotor 13 and the impeller 20 in the axial direction (parallel to the rotation axis 21).

[0087] During the levitation process of the impeller 20, the first position sensor 51 can monitor the levitation height of the impeller 20 in real time. After the impeller 20 levitates to the first position, the control unit 33 can control the rotor 13 to rotate. In this application, the levitation height refers to the axial distance between the first rotor 13 and the first position sensor 51. Since the positions of the first position sensor 51 and the first stator 110 are fixed, the levitation height can also refer to the axial distance between the first rotor 130 and the first stator 110 or the first winding unit and the second winding unit, which can be characterized by the magnetic flux intensity detected by the first position sensor 51.

[0088] The first position is located within a preset suspension range, which is near the center of the first chamber 30. For example, the preset suspension range is 0.05mm-0.5mm.

[0089] After the impeller 20 is suspended in the first position, the control unit 33 can control the impeller 20 to rotate through the second stator 120. The control unit 33 applies a third current to the first stator 110 to control the impeller 20 to rotate in the first position, so that the impeller 20 is not in contact with the housing assembly when rotating, thereby reducing or avoiding friction between the impeller 20 and the housing assembly.

[0090] Specifically, the control unit 33 provides three-phase alternating current to the second three-phase winding in the second stator 120. Each phase of the alternating current is 120 degrees out of phase. The second three-phase winding, controlled by applying alternating current to the winding units of phases U, V, and W, generates a torsional force relative to the second rotor 140. This torsional force causes the drive impeller 20 to rotate along the rotation axis 21 of the impeller.

[0091] Optionally, after applying a third current to the second stator, the method further includes: obtaining a target magnetic pole angle, the target magnetic pole angle being the magnetic pole angle detected by the second position sensor; and controlling the application of a fourth current to the first stator according to the target magnetic pole angle.

[0092] During the rotation of impeller 20, it is necessary to stabilize impeller 20 in the first position to improve the stability and efficiency of motor 10 operation. Therefore, the magnitude and direction of the force exerted by the first stator 110 on the first rotor 130 in the axial direction must remain unchanged. However, during the rotation of the second rotor 140, the first rotor 130 causes the impeller 20 to rotate synchronously, resulting in continuous alternating changes in the magnetism of the magnetic blocks of the first rotor 130 directly opposite the first winding unit of the first three-phase winding. The change in magnetic poles in the first rotor 130 alters the direction and / or magnitude of the force exerted by the first stator 110 on the first rotor 130, causing the impeller 20 to become unstable and suspended.

[0093] Based on this, after applying the third current to the second stator 120, the control unit 33 determines the fourth current to be applied to the first stator 110 based on the magnetic pole angle of the first rotor 130 relative to the first stator 110. During the rotation of the second rotor 140, the second position sensor 52 detects the magnetic pole angle of the second rotor 140 relative to the second stator 120 in real time. This magnetic pole angle is the angle between the magnetic block on the second rotor 140 and the second winding unit in the second stator 120, i.e., the angle between the zero-point line P of the stator 11 and the zero-point line O of the rotor 13. At the initial zero-point position, this magnetic pole angle is 0.

[0094] In this application, the magnetic force generated between the first rotor 130 and the first stator 110 causes the impeller 20 to be suspended at the first position. In order to keep the impeller 20 suspended at the first position, the magnitude and direction of the magnetic force generated between the first rotor 130 and the first stator 110 in the axial direction remain unchanged. Therefore, the control unit 33 can keep the magnitude of the current applied to the first stator 110 constant, so as to keep the magnitude of the magnetic force generated by it constant, and then determine the direction of the current according to the change of the magnetic poles of the magnetic blocks in the first rotor 130.

[0095] Since the magnetic blocks in the first rotor 130 and the second rotor 140 are placed in the same way, the control unit 33 acquires the target magnetic pole angle detected by the second position sensor 52, and determines the first winding unit that is directly opposite the magnetic block in the first rotor 130 based on the target magnetic pole angle. Then, by applying a fourth current to the first winding unit that is directly opposite the magnetic block, the magnitude of the axial magnetic force generated between the first winding unit and the first rotor 130 remains unchanged, and the direction of applying the fourth current is determined by determining the magnetic pole of the magnetic block directly opposite the first rotor 130.

[0096] Optionally, the step of controlling the application of a fourth current to the first stator according to the target magnetic pole angle includes: when the target magnetic pole angle is a first angle, applying the fourth current to a first phase winding unit in the first three-phase winding unit, wherein the first angle is such that the first phase winding unit in the first three-phase winding unit is directly opposite a target magnetic block in the rotor, and the target magnetic block is a magnetic block with N or S poles; when the target magnetic pole angle is a second angle, applying the fourth current to a second phase winding unit in the first three-phase winding unit, wherein the second angle is such that the second phase winding unit in the first three-phase winding unit is directly opposite the target magnetic block in the rotor; and when the target magnetic pole angle is a third angle, applying the fourth current to a third phase winding unit in the first three-phase winding unit, wherein the third angle is such that the third phase winding unit in the first three-phase winding unit is directly opposite the target magnetic block in the rotor.

[0097] Specifically, when the magnetic pole of the target magnetic block is the N pole, the current direction of the fourth current is the same as that of the second current; when the magnetic pole of the target magnetic block is the S pole, the current direction of the fourth current is opposite to that of the second current.

[0098] Since the magnetic blocks in the first rotor 130 and the second rotor 140 are arranged in the same way, the positions of the first three-phase winding and the second three-phase winding are also the same. For example, when the magnetic pole of the magnetic block where the zero line O of the rotor 13 is located is the N pole, if the magnetic pole of the magnetic block directly opposite the first winding unit in the current first rotor 130 is still the N pole, the control unit 33 can apply a fourth current to the first stator 110 with the same current direction and magnitude as the second current; if the magnetic pole of the magnetic block directly opposite the first winding unit in the current first rotor 130 becomes the S pole, the control unit 33 can apply a fourth current to the first stator 110 with the opposite current direction and the same current magnitude as the second current, so that the magnitude and direction of the magnetic force generated in the axial direction between the first stator 110 and the first rotor 130 remain unchanged, and the impeller 20 can be stably suspended in the first position during the suspension process.

[0099] For example, when the magnetic pole of the magnetic block where the zero line O of the rotor 13 is located is the S pole, if the magnetic pole of the magnetic block directly opposite the first winding unit in the current first rotor 130 becomes the N pole, the control unit 33 can apply a fourth current to the first stator 110 with the opposite current direction and the same current magnitude as the second current; if the magnetic pole of the magnetic block directly opposite the first winding unit in the current first rotor 130 is still the S pole, the control unit 33 can apply a fourth current to the first stator 110 with the same current direction and current magnitude as the second current, so that the magnitude and direction of the magnetic force generated in the axial direction between the first stator 110 and the first rotor 130 remain unchanged, and the impeller 20 can be stably suspended in the first position during the suspension process.

[0100] The target magnetic block is the magnetic block directly opposite the first winding unit. If the first winding unit directly opposite the target magnetic block is a first-phase winding unit, the fourth current can be applied to the first-phase winding unit in the first stator 110; if the first winding unit directly opposite the target magnetic block is a second-phase winding unit, the fourth current can be applied to the second-phase winding unit in the first stator 110; if the first winding unit directly opposite the target magnetic block is a third-phase winding unit, the fourth current can be applied to the third-phase winding unit in the first stator 110. The first three-phase windings in the first stator 110 respectively include a U-phase winding unit, a V-phase winding unit, and a W-phase winding unit. The first-phase winding unit can be a U-phase winding unit, the second-phase winding unit can be a V-phase winding unit, and the third-phase winding unit can be a W-phase winding unit.

[0101] For example, taking a first stator 110 and a second stator 120 comprising 6 winding units, and a first rotor 130 and a second rotor 140 comprising 8 magnetic blocks as an example, the starting process of the motor 10 is explained in detail. The positions of the stator 11 and the rotor 13 are as follows: Figures 7-19 .

[0102] In this design, the first stator 110 controls the levitation of the impeller 20, and the second stator 120 controls the rotation of the impeller 20. The stator cores and stator coils of the first stator 110 and the second stator 120 have the same distribution angle, and the magnetic poles of the first rotor 130 and the second rotor 140 have the same distribution. The first stator 110 and the first rotor 130 form the first motor, and the second stator 120 and the second rotor 140 form the second motor. The first rotor 130 and the second rotor 140 are fixedly connected to the impeller 20. The first motor and the second motor are independently controlled and can synchronously control the levitation and / or rotation of the impeller 20. The first winding unit 111 and the second winding unit 121 are U-phase winding units, the first winding unit 112 and the second winding unit 122 are W-phase winding units, and the first winding unit 113 and the second winding unit 123 are V-phase winding units. (See figure) Indicates the N pole. This indicates the S pole.

[0103] When the ventricular assist device 100 is not activated, the impeller 20 is attracted by the stator cores of the first stator 110 and the second stator 120, causing the impeller 20 to rest against the second cavity wall 32. Since no current is applied to the stator 11, the first position sensor 51 and the second position sensor 52 cannot detect it, and the overlap between the zero line of the stator 11 and the zero line of the rotor 13 is unknown. The zero line of the stator 11 is the P line, and the zero line of the rotor 13 is the O line.

[0104] After receiving the start command, the control unit 33 applies a first current to the first winding unit 111 and the first winding unit 114, and applies a first current to the second winding unit 121 and the second winding unit 124 at time T1, so that the first winding unit 111, the first winding unit 114, the second winding unit 121 and the second winding unit 124 exhibit S-pole magnetism. The position of the rotor 13 relative to the stator 11 at time T1 is... Figure 7 As shown. Based on the principle of attraction between opposite poles, the first winding unit 111, the first winding unit 114, the second winding unit 121, and the second winding unit 124 will attract the magnetic blocks with N poles in the first rotor 130 and the second rotor 140, causing the rotor 13 to rotate along its circumference. The projection of the zero line P of the stator 11 and the projection of the zero line O of the rotor 13 coincide in the target plane.

[0105] To levitate the impeller 20 to the first position, the projections of the stator 11 zero-point line P and the rotor 13 zero-point line O coincide on the target plane, causing magnetic blocks 131, 135, 141, and 145, whose magnetic poles are N, to be directly opposite the first winding unit 111, the first winding unit 114, the second winding unit 121, and the second winding unit 124, respectively. At time T2, the control unit 33 applies a second current to the first winding unit 111 and the first winding unit 114, respectively. This second current is opposite in direction to the first current, causing the first winding unit 111 and the first winding unit 114 to exhibit N-pole magnetism. The positions of the rotor 13 and the stator 11 at time T2 are as follows: Figure 8 and Figure 9 As shown. The first winding unit 111 and the first winding unit 114, which are magnetically N poles, generate an axial magnetic thrust F with the magnetic blocks 131 and 135, which are magnetically N poles. This magnetic thrust F moves the impeller 20 axially to the first position.

[0106] After suspending the impeller 20 to the first position, the control unit 33 initiates the rotation of the impeller 20. The control unit 33 inputs three-phase AC current to the second three-phase winding to drive the second rotor 140 to rotate counterclockwise, wherein each three-phase AC current is separated by an equal phase difference of 120 degrees. During the rotation of the second rotor 140, the second position sensor 52 detects the magnetic pole angle of the second rotor 140 in real time. If at time T3, it is detected that magnetic blocks 134, 144, 138, and 148 are directly facing the first winding unit 113, the second winding unit 123, the first winding unit 116, and the second winding unit 126, respectively, and since the magnetic poles of magnetic blocks 134, 144, 138, and 148 are S poles, the control unit 33 applies second currents of opposite directions and the same magnitude to the first winding unit 113 and the first winding unit 116, respectively, causing the first winding unit 113 and the first winding unit 116 to exhibit S pole magnetism. The positions of the rotor 13 and the stator 11 at time T3 are as follows: Figure 10 and Figure 11 As shown. The first winding unit 113 and the first winding unit 116, which have S pole magnetism, generate an axial magnetic thrust F with the magnetic blocks 134 and 138, which have S pole magnetism, respectively. This magnetic thrust F keeps the impeller 20 suspended in the first position.

[0107] If at time T4, it is detected that magnetic blocks 133, 143, 137, and 147 are directly facing the first winding unit 112, the second winding unit 122, the first winding unit 115, and the second winding unit 125, respectively, and since the magnetic poles of magnetic blocks 133, 143, 137, and 147 are N poles, the control unit 33 applies a second current of the same direction and magnitude to the first winding unit 112 and the first winding unit 115, respectively, causing the first winding unit 112 and the first winding unit 115 to exhibit N pole magnetism. The positions of the rotor 13 and the stator 11 at time T4 are as follows: Figure 12 and Figure 13 As shown. The first winding unit 112 and the first winding unit 115, which are N-pole magnets, generate an axial magnetic thrust F with the magnetic blocks 133 and 137, which are also N-pole magnets. This magnetic thrust F keeps the impeller 20 suspended in the first position.

[0108] If at time T5, it is detected that magnetic blocks 132, 142, 136, and 146 are directly facing the first winding unit, the second winding unit, the first winding unit 114, and the second winding unit 124, respectively, since the magnetic poles of magnetic blocks 132, 142, 136, and 146 are S poles, the control unit 33 applies second currents of opposite directions and the same magnitude to the first winding unit and the first winding unit 114, respectively, causing the first winding unit and the first winding unit 114 to exhibit S pole magnetism. The positions of the rotor 13 and the stator 11 at time T5 are as follows: Figure 14 and Figure 15 As shown. The first winding unit 114, which has an S pole magnetism, generates an axial magnetic thrust F with the magnetic blocks 132 and 136, which also have an S pole magnetism. This magnetic thrust F keeps the impeller 20 suspended in the first position.

[0109] If at time T6, it is detected that magnetic blocks 133, 143, 137, and 147 are directly facing the first winding unit 113, the second winding unit 123, the first winding unit 116, and the second winding unit 126, respectively, and since the magnetic poles of magnetic blocks 133, 143, 137, and 147 are N poles, the control unit 33 applies a second current of the same direction and magnitude to the first winding unit 113 and the first winding unit 116, respectively, causing the first winding unit 113 and the first winding unit 116 to exhibit N pole magnetism. The positions of the rotor 13 and the stator 11 at time T6 are as follows: Figure 16 and Figure 17 As shown. The first winding unit 113 and the first winding unit 116, which are N-pole magnets, generate an axial magnetic thrust F with the magnetic blocks 133 and 137, which are also N-pole magnets. This magnetic thrust F keeps the impeller 20 suspended in the first position.

[0110] If at time T7 it is detected that magnetic blocks 134, 144, 138, and 148 are directly facing the first winding unit 112, the second winding unit 122, the first winding unit 115, and the second winding unit 125 respectively, since the magnetic poles of magnetic blocks 134, 144, 138, and 148 are S poles, the control unit 33 applies second currents of opposite directions and the same magnitude to the first winding unit 112 and the first winding unit 115 respectively, causing the first winding unit 112 and the first winding unit 115 to exhibit S pole magnetism. The positions of the rotor 13 and the stator 11 at time T7 are as follows: Figure 18 and Figure 19 As shown. The first winding unit 112 and the first winding unit 115, which are magnetic poles, generate an axial magnetic thrust F with the magnetic blocks 134 and 138, which are magnetic poles, respectively. This magnetic thrust F keeps the impeller 20 suspended in the first position.

[0111] The rotor 13 rotates through six time points: t2, t3, t4, t5, t6, and t7. If the control unit 33 cyclically controls the current applied to the first stator 110, at each time point, the control unit 33 determines the direction of applying the fourth current to the first winding unit based on the magnetic pole angle of the second rotor 140, thereby achieving stable levitation and control of the impeller 20 to rotate at the first position.

[0112] In this application, the first stator 110 controls the impeller 20 to levitate, and the second stator 120 controls the impeller 29 to rotate. This avoids friction between the impeller 20 and the housing assembly when the impeller 20 starts rotating, preventing fluid embolism or condensation caused by damage to the inner wall surface of the housing assembly due to friction. Furthermore, the current controlling the levitation of the impeller 20 and the current controlling its rotation can be independently decoupled and controlled. The arrangement of the first and second motors also prevents the other motor from continuing to operate in the event of a failure in one motor, improving the safety and service life of the motor 10.

[0113] As can be seen, this application proposes a method for starting a ventricular assist device. At a first moment, a first current is applied to the first and second stators, aligning the zero-point lines of the stators and rotor. At a second moment, the application of the first current to the second stator is stopped, and a second current is applied to the first stator to suspend the rotor. After suspending the rotor to the first position, a third current is applied to the second stator to control the rotor to rotate at the target speed from the first position. This application uses two stators: the first stator controls the rotor to suspend at the first position, and the second stator controls the rotor to rotate at the first position. This suspends the rotor before rotation, avoiding frictional resistance when the impeller slides relative to the housing, thereby reducing thrombus formation caused by surface damage to the inner wall of the impeller and housing, and improving user safety.

[0114] The above primarily describes the solutions of the embodiments of this application from the perspective of the method execution process. It is understood that, in order to achieve the above functions, the network device includes corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the various examples described in the embodiments provided herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0115] For example, this application also provides a control unit for a ventricular assist device, the ventricular assist device including a housing, an impeller disposed within the housing, and a motor for driving the impeller to rotate in a suspended manner. The motor includes a rotor embedded in the impeller and a stator for driving the rotor to rotate in a suspended manner. The stator includes a first stator and a second stator. The control unit includes one or more processors, the one or more processors being used for:

[0116] At the first moment, a first current is applied to the first stator and the second stator to make the zero line of the stator coincide with that of the rotor;

[0117] At the second moment, the first current is stopped being applied to the second stator, and the second current is applied to the first stator to suspend the rotor;

[0118] After suspending the rotor to the first position, a third current is applied to the second stator to control the rotor to rotate at the first position.

[0119] For example, this application also provides a ventricular assist device, the ventricular assist device comprising:

[0120] case;

[0121] An impeller disposed within the housing;

[0122] An electric motor that drives the impeller to rotate in a suspended manner, the electric motor including a rotor embedded in the impeller and a stator that drives the rotor to rotate in a suspended manner, the stator including a first stator and a second stator;

[0123] The control unit connected to the motor is used to perform some or all of the steps described in the method described above.

[0124] For example, this application also provides a medical device that includes the control unit or ventricular assist device described above.

[0125] The control unit of each of the above solutions has the function of implementing the corresponding steps performed by the medical device in the above method; the function can be implemented by hardware or by hardware executing corresponding software.

[0126] In embodiments of this application, the control unit may also be a chip or a chip system, such as a system on a chip (SoC).

[0127] Please see Figure 20 , Figure 20 This is a schematic diagram of the structure of a medical device provided in an embodiment of this application. The medical device includes: one or more processors, one or more memories, one or more communication interfaces, and one or more programs; the one or more programs are stored in the memories and configured to be executed by the one or more processors.

[0128] The above procedure includes instructions for performing the following steps:

[0129] At the first moment, a first current is applied to the first stator and the second stator to make the zero line of the stator coincide with that of the rotor;

[0130] At the second moment, the first current is stopped being applied to the second stator, and the second current is applied to the first stator to suspend the rotor;

[0131] After suspending the rotor to the first position, a third current is applied to the second stator to control the rotor to rotate at the first position.

[0132] All relevant content in each scenario involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0133] It should be understood that the aforementioned memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of the memory may also include non-volatile random access memory. For example, the memory may also store information about the device type.

[0134] In the embodiments of this application, the processor of the above-described device may be a Central Processing Unit (CPU), which may also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0135] It should be understood that "at least one" in the embodiments of this application refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0136] Furthermore, unless otherwise stated, the ordinal numbers such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects and are not used to limit the order, timing, priority, or importance of multiple objects. For example, "first information" and "second information" are only used to distinguish different information and do not indicate differences in the content, priority, sending order, or importance of these two types of information.

[0137] In implementation, each step of the above method can be completed by integrated logic circuits in the processor's hardware or by instructions in software. The steps of the method disclosed in the embodiments of this application can be directly manifested as execution by a hardware processor, or as a combination of hardware and software units within the processor. The software units can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory, and the processor executes the instructions in the memory, combining them with its hardware to complete the steps of the above method. To avoid repetition, detailed descriptions are omitted here.

[0138] This application also provides a computer storage medium storing a computer program for electronic data interchange, which causes a computer to perform some or all of the steps of any of the methods described in the above method embodiments.

[0139] This application also provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps of any of the methods described in the above method embodiments. This computer program product can be a software installation package.

[0140] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0141] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0142] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical or other forms.

[0143] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments of this application, depending on actual needs.

[0144] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0145] If the aforementioned integrated units are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or TRP, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0146] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage device, which may include a flash drive, ROM, RAM, disk, or optical disk, etc.

[0147] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A control unit for a ventricular assist device, characterized in that, The ventricular assist device includes a housing, an impeller disposed within the housing, and a motor for driving the impeller to levitate and rotate. The motor includes a rotor fixedly connected to the impeller and a stator for driving the rotor to levitate and rotate. The rotor includes a first rotor and a second rotor, both of which are annular, concentric, and coaxial. Both the first rotor and the second rotor include multiple magnetic blocks. The multiple magnetic blocks of the first rotor are assembled into a first annular structure, and the multiple magnetic blocks of the second rotor are assembled into a second annular structure. The positions of the multiple magnetic blocks of the first rotor correspond one-to-one with the positions of the multiple magnetic blocks of the second rotor to form multiple corresponding magnetic block groups. In each magnetic block group, the magnetization direction of the magnetic blocks of the first rotor and the magnetic blocks of the second rotor is the same, and the outer peripheral wall of the magnetic blocks of the first rotor is opposite to the inner peripheral wall of the magnetic blocks of the second rotor. The stator includes a first stator and a second stator. The control unit is used to perform the following steps: At the first moment, a first current is applied to the first stator and the second stator to make the zero line of the stator coincide with that of the rotor; At the second moment, the first current is stopped being applied to the second stator, and the second current is applied to the first stator to suspend the rotor; After suspending the rotor to the first position, a third current is applied to the second stator to control the rotor to rotate at the first position.

2. The control unit according to claim 1, characterized in that, The direction of the second current is opposite to the direction of the first current.

3. The control unit according to claim 1 or 2, characterized in that, The first stator includes 3N first winding units, and the second stator includes 3N second winding units. The 3N first winding units are arranged at equal intervals along a first circle, and the 3N second winding units are arranged at equal intervals along a second circle. The first circle and the second circle are concentric, and N is greater than or equal to 1.

4. The control unit according to claim 3, characterized in that, Along the central axis of the first rotor, the position of the first stator corresponds to the position of the first rotor, and is used to drive the first rotor to levitate and / or rotate; along the central axis of the second rotor, the position of the second stator corresponds to the position of the second rotor, and is used to drive the second rotor to levitate and / or rotate.

5. The control unit according to claim 3, characterized in that, In each of the magnetic block groups, the central angle corresponding to the sector ring where the magnetic block of the first rotor is located is equal to the central angle corresponding to the sector ring where the magnetic block of the second rotor is located.

6. The control unit according to claim 4, characterized in that, The outer peripheral wall of the first rotor is fixedly connected to the inner peripheral wall of the second rotor.

7. The control unit according to claim 3, characterized in that, The ventricular assist device further includes 3N first position sensors and 3N second position sensors. Each first position sensor is disposed between two adjacent first winding units. The first position sensor is used to measure the levitation height and magnetic pole angle of the first rotor relative to the first winding unit. Each second position sensor is disposed between two adjacent second winding units. The second position sensor is used to measure the levitation height and magnetic pole angle of the second rotor relative to the second winding unit.

8. The control unit according to claim 3, characterized in that, The ventricular assist device further includes 3N first position sensors and 3N second position sensors. Each first position sensor is disposed between two adjacent first winding units and is used to measure the levitation height and magnetic pole angle of the rotor relative to the first winding unit. Each second position sensor is disposed between two adjacent second winding units and is used to measure the levitation height and magnetic pole angle of the rotor relative to the second winding unit.

9. The control unit according to claim 7 or 8, characterized in that, After applying a third current to the second stator, the control unit is further configured to perform the following steps: Obtain the target magnetic pole angle, which is the magnetic pole angle detected by the second position sensor; A fourth current is applied to the first stator according to the target magnetic pole angle.

10. The control unit according to claim 9, characterized in that, Every three adjacent first winding units form a first three-phase winding, and every three adjacent second winding units form a second three-phase winding; along the radial direction of the first stator and / or the second stator, the positions of the first three-phase windings correspond one-to-one with the positions of the second three-phase windings; In applying a first current to the first stator and the second stator to align the zero-point line of the stator with that of the rotor, the control unit performs the following steps: The first current is applied to the first phase winding unit in the first three-phase winding and the second three-phase winding respectively, so that the projection of the center line of the first phase winding unit in the first three-phase winding and the projection of the center line of the first phase winding unit in the second three-phase winding coincide with the projection of the zero line of the rotor on the target plane. The zero line is the center line of any magnetic block group or magnetic block in the rotor, and the target plane is a plane perpendicular to the central axis of the first stator and / or the second stator.

11. The control unit according to claim 10, characterized in that, In controlling the application of a fourth current to the first stator according to the target magnetic pole angle, the control unit performs the following steps: When the target magnetic pole angle is the first angle, the fourth current is applied to the first phase winding unit in the first three-phase winding. The first angle is when the first phase winding unit in the first three-phase winding is directly opposite the target magnetic block in the rotor. The target magnetic block is a magnetic block with the magnetic pole near the stator side being the N pole or the S pole. When the target magnetic pole angle is the second angle, the fourth current is applied to the second phase winding unit in the first three-phase winding, where the second phase winding unit in the first three-phase winding is directly opposite the target magnetic block in the rotor; When the target magnetic pole angle is the third angle, the fourth current is applied to the third phase winding unit in the first three-phase winding, where the third angle is when the third phase winding unit in the first three-phase winding is directly opposite the target magnetic block in the rotor.

12. The control unit according to claim 11, characterized in that, When the magnetic pole of the target magnetic block is N, the direction of the fourth current is the same as the direction of the second current. When the magnetic pole of the target magnetic block is the S pole, the current direction of the fourth current is opposite to the current direction of the second current.

13. A ventricular assist device, characterized in that, The ventricular assist device includes: case; An impeller disposed within the housing; A motor driving the impeller to levitate and rotate includes a rotor connected to the impeller and a stator driving the rotor to levitate and rotate. The rotor includes a first rotor and a second rotor, both of which are annular, concentric, and coaxial. Each rotor includes multiple magnetic blocks. The multiple magnetic blocks of the first rotor are assembled into a first annular structure, and the multiple magnetic blocks of the second rotor are assembled into a second annular structure. The positions of the multiple magnetic blocks of the first rotor correspond one-to-one with the positions of the multiple magnetic blocks of the second rotor to form multiple corresponding magnetic block groups. In each magnetic block group, the magnetization direction of the magnetic blocks of the first rotor and the magnetic blocks of the second rotor is the same, and the outer peripheral wall of the magnetic blocks of the first rotor is opposite to the inner peripheral wall of the magnetic blocks of the second rotor. The stator includes a first stator and a second stator. A control unit connected to the motor, the control unit being used to perform the steps as described in any one of claims 1-12.

14. A medical device, characterized in that, The device includes a processor, a memory, and a communication interface, wherein the memory stores one or more programs, and the one or more programs are executed by the processor, the one or more programs including instructions for performing the steps as described in any one of claims 1-12.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program for electronic data interchange, wherein the computer program causes a computer to perform the steps as described in any one of claims 1-12.

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