Magnetic levitation motor system of an implantable magnetic levitation blood pump

Abstract

The embodiment of the application provides a kind of implantable magnetic suspension blood pump's magnetic suspension motor system, it is related to medical instrument technical field, motor control mainboard integrates central control module, motor drive module, closed loop feedback module;The closed loop feedback module detects the suspension offset data and actual operating current of the rotor, and the central control module is fed back by double closed loop;Central control module utilizes the suspension offset data and actual operating current, adopts built-in control algorithm, generates pulse width modulation PWM control signal, and the motor drive module converts PWM control signal into suspension current and rotating current, suspension current includes the first current for maintaining the radial suspension of rotor and the second current for maintaining the axial suspension of rotor, and the current of the electromagnetic coil is adjusted using the suspension current and rotating current, to maintain the suspension rotation of rotor.The system provided by the embodiment can improve the stability of the suspension rotation of the magnetic suspension motor.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a magnetic levitation motor system for an implantable magnetic levitation blood pump. Background Technology

[0002] A blood pump is an artificial mechanical device that assists the heart in pumping blood and improves systemic circulation. Implantable magnetic levitation blood pumps can be used for long-term support in patients with cardiovascular diseases. The core component of an implantable magnetic levitation blood pump is the magnetic levitation motor, and how to achieve stable levitation and rotation of the magnetic levitation motor is an urgent problem to be solved. Summary of the Invention

[0003] The purpose of this application is to provide a magnetic levitation motor system for an implantable magnetic levitation blood pump, so as to improve the stability of the levitation rotation of the magnetic levitation motor. The specific technical solution is as follows:

[0004] In a first aspect, embodiments of this application provide a magnetic levitation motor system for an implantable magnetic levitation blood pump, the magnetic levitation motor system comprising a magnetic levitation motor and a motor control device, wherein:

[0005] The magnetic levitation motor includes an electromagnetic coil and a rotor. The rotor achieves levitation and rotation through the electromagnetic force between itself and the electromagnetic coil, thus realizing the operation of the magnetic levitation motor.

[0006] The motor control device integrates a motor control motherboard, which controls the operation of the magnetic levitation motor. The motor control motherboard integrates a central control module, a motor drive module, and a closed-loop feedback module.

[0007] The closed-loop feedback module detects the rotor's levitation offset data and actual operating current, and feeds this data back to the central control module through a dual closed-loop feedback mechanism. The central control module uses the levitation offset data and actual operating current, employing a built-in control algorithm, to generate a pulse width modulation (PWM) control signal. The motor drive module converts the PWM control signal into a levitation current and a rotational current. The levitation current includes a first current that maintains the rotor's radial levitation and a second current that maintains the rotor's axial levitation. The levitation current and rotational current are used to adjust the current in the electromagnetic coil to maintain the rotor's levitation and rotation.

[0008] In one embodiment of this application, the closed-loop feedback module includes a rotor position detection circuit and a current detection circuit. The input end of the rotor position detection circuit is connected to the rotor, and the output end is connected to the first interface of the central control module. The input end of the current detection circuit is connected to the motor drive module, and the output end is connected to the second interface of the central control module. The rotor position detection circuit detects the rotor's suspension offset data, and the current detection circuit detects the rotor's actual operating current.

[0009] In one embodiment of this application, the current detection circuit includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, a second capacitor C2, and an operational amplifier U1, wherein:

[0010] One end of the first resistor R1 is connected to the first voltage acquisition port of the motor drive module, and the other end is connected to the inverting input terminal of the operational amplifier U1. The other end of the first resistor R1 is also connected to one end of the third resistor R3.

[0011] One end of the second resistor R2 is connected to the second voltage acquisition port of the motor drive module, and the other end is connected to the non-inverting input terminal of the operational amplifier U1. The other end of the second resistor R2 is also connected to one end of the fourth resistor R4.

[0012] The inverting input terminal of the operational amplifier U1 is also connected to one end of the first capacitor C1, and the other end of the first capacitor C1 is grounded.

[0013] The non-inverting input terminal of the operational amplifier U1 is also connected to one end of the second capacitor C2, and the other end of the second capacitor C2 is grounded.

[0014] The output terminal of the operational amplifier U1 is connected to one end of the fifth resistor R5, and the other end of the fifth resistor R5 serves as the output port. The output terminal of the operational amplifier U1 is also connected to the other end of the third resistor R3.

[0015] In one embodiment of this application, the first resistor R1 and the second resistor R2 have the same resistance value, the resistance values ​​of the first resistor R1 and the second resistor R2 are between [4kΩ and 6kΩ], the resistance value of the third resistor R3 is between [9kΩ and 11kΩ], the resistance value of the fourth resistor R4 is between [9kΩ and 11kΩ], and the resistance value of the fifth resistor R5 is between [9kΩ and 11kΩ].

[0016] In one embodiment of this application, the capacitance values ​​of the first capacitor C1 and the second capacitor C2 are the same, and the capacitance values ​​of the first capacitor C1 and the second capacitor C2 are between [0.05uF and 0.15uF].

[0017] In one embodiment of this application, the rotor position detection circuit includes a Hall sensor U2, a sixth resistor R6, a third capacitor C3, and a fourth capacitor C4, wherein:

[0018] The VCC interface of the Hall sensor U2 is connected to one end of the third capacitor C3 and the VREF interface, respectively, and the other end of the third capacitor C3 is grounded; the OUT interface of the Hall sensor U2 is connected to one end of the fourth capacitor C4, and the other end of the fourth capacitor C4 is connected to the sixth resistor R6, which is grounded; the GND interface of the Hall sensor U2 is grounded; the #SLEEP interface of the Hall sensor U2 is connected to the VREF interface.

[0019] In one embodiment of this application, the capacitance value of the third capacitor C3 is between [90nF and 110nF], the capacitance value of the fourth capacitor C4 is between [90nF and 110nF], and the resistance value of the sixth resistor R6 is between [9kΩ and 11kΩ].

[0020] As can be seen from the above, in the system provided by the embodiments of this application, the closed-loop feedback module uses the closed-loop feedback rotor suspension offset data and real-time operating current. The central control module determines the control signal based on the data fed back by the closed-loop feedback module. The motor drive signal then uses the control signal to generate a control current. Since the control current includes suspension current and rotation current, and the suspension current includes a first current to maintain the radial suspension of the rotor and a second current to maintain the axial suspension of the rotor, the above-mentioned control current can maintain the radial and axial suspension of the rotor and realize the rotor rotation. Therefore, by adopting the above-mentioned magnetic levitation motor system, the suspension and rotation stability of the magnetic levitation motor can be improved.

[0021] Of course, implementing any product or method of this application does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0023] Figure 1 This application provides a schematic diagram of the structure of a magnetic levitation motor system for an implantable magnetic levitation blood pump.

[0024] Figure 2 This is a schematic diagram of the structure of a first type of motor control motherboard provided in an embodiment of this application;

[0025] Figure 3 This is a schematic diagram of the structure of a second type of motor control motherboard provided in an embodiment of this application;

[0026] Figure 4 A schematic diagram of the circuit structure of a current detection circuit provided in an embodiment of this application;

[0027] Figure 5 This is a schematic diagram of a rotor position detection circuit provided in an embodiment of this application. Detailed Implementation

[0028] The technical solutions of 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 embodiments of this application, all other embodiments obtained by those skilled in the art based on this application are within the scope of protection of this application.

[0029] See Figure 1 , Figure 1 This is a schematic diagram of the structure of a magnetic levitation motor system for an implantable magnetic levitation blood pump provided in an embodiment of this application. The magnetic levitation motor system includes a magnetic levitation motor 11 and a motor control device 12.

[0030] The magnetic levitation motor 11 drives the impeller in the implantable magnetic levitation blood pump to rotate, thus enabling the implantable magnetic levitation blood pump to operate. The implantable magnetic levitation blood pump is implanted in the patient's heart, located at the apex of the heart, to pump blood into the arterial system.

[0031] The magnetic levitation motor 11 mainly achieves rotor levitation and rotation through the electromagnetic force between the electromagnetic coil and the rotor, thus enabling the magnetic levitation motor 11 to operate.

[0032] The motor control device 12 is located outside the patient's body, monitoring physiological and operational data, and controlling the operation of the magnetic levitation blood pump in real time. The motor control device 12 integrates a motor control motherboard, which controls the operation of the magnetic levitation motor 11.

[0033] The structure of the motor control mainboard is as follows: Figure 2 As shown. Based on this, see [link / reference]. Figure 2 , Figure 2 This is a schematic diagram of the structure of the first type of motor control motherboard provided in the embodiments of this application. The motor control motherboard integrates a central control module 201, a motor drive module 202, and a closed-loop feedback module 203.

[0034] The closed-loop feedback module 203 detects the rotor's suspension offset data and actual operating current, and feeds back to the central control module 201 through a dual closed-loop feedback mechanism.

[0035] The aforementioned suspension offset data represents the offset information during the rotor's suspension process, including the rotor's axial offset, radial offset, etc.; the actual operating current represents the real-time current information of the magnetic levitation motor.

[0036] The central control module 201 uses the floating offset data and the actual operating current to generate a PWM (Pulse Width Modulation) control signal using a built-in control algorithm.

[0037] The aforementioned built-in control algorithm can be any control algorithm in the existing technology, such as PID (Proportion-Integration-Differentiation) control, etc.

[0038] The PWM control signal is used to control the magnetic levitation motor to maintain its smooth operation. The PWM control signal includes a levitation control signal and a rotating current control signal.

[0039] The motor drive module 202 converts the PWM control signal into a floating current and a rotating current, and uses the floating current and rotating current to adjust the current of the electromagnetic coil in order to maintain the rotor's floating rotation.

[0040] The motor drive module has a built-in motor drive chip. The PWM control signals include a levitation control signal and a rotational current control signal. Using the motor drive chip, the corresponding control signals in the PWM control signals can be converted into corresponding current signals, namely levitation current and rotational current. The aforementioned levitation current includes a first current that maintains the radial levitation of the rotor and a second current that maintains the axial levitation of the rotor.

[0041] The electromagnetic coil includes a radial electromagnetic coil, an axial electromagnetic coil, and a rotating electromagnetic coil. The first current is input to the radial electromagnetic coil, the second current is input to the axial electromagnetic coil, and the rotating current is input to the rotating electromagnetic coil. By using the above three current signals, the stability of the rotor's levitation and rotation is achieved.

[0042] As can be seen from the above, in the system provided in this embodiment, the closed-loop feedback module uses the closed-loop feedback rotor suspension offset data and real-time operating current. The central control module determines the control signal based on the data fed back by the closed-loop feedback module. The motor drive signal then uses the control signal to generate a control current. Since the control current includes suspension current and rotation current, and the suspension current includes a first current to maintain the radial suspension of the rotor and a second current to maintain the axial suspension of the rotor, the above-mentioned control current can maintain the radial and axial suspension of the rotor and realize the rotor rotation. Therefore, by using the above-mentioned magnetic levitation motor system, the suspension and rotation stability of the magnetic levitation motor can be improved.

[0043] In the foregoing Figure 2 In the corresponding embodiment, the specific structure of the closed-loop feedback module is as follows: Figure 3 As shown, based on this, see Figure 3 . Figure 3This is a schematic diagram of the structure of a second type of motor control motherboard provided in an embodiment of this application. Figure 3 The motor control motherboard shown includes a central control module 301, a motor drive module 302, and a closed-loop feedback module 303.

[0044] The closed-loop feedback module 303 includes a rotor position detection circuit 3031 and a current detection circuit 3032.

[0045] The rotor position detection circuit 3031 has its input terminal connected to the rotor and its output terminal connected to the first interface of the central control module 301. The rotor position detection circuit 3031 detects the rotor's suspension offset data. The current detection circuit 3032 has its input terminal connected to the motor drive module 302 and its output terminal connected to the second interface of the central control module 301. The current detection circuit 3032 detects the rotor's actual operating current.

[0046] The rotor position detection circuit 3031 feeds back the suspension offset data to the central control module 301 through the first closed-loop feedback loop; the current detection circuit 3032 feeds back the actual operating current to the central control module 301 through the second closed-loop feedback loop.

[0047] The central control module 301 uses the floating offset data and the actual operating current to generate a PWM control signal using a built-in control algorithm.

[0048] The motor drive module 302 converts the PWM control signal into a levitation current and a rotational current. It uses these levitation currents and rotational currents to adjust the current in the electromagnetic coil to maintain the rotor's levitation rotation. The levitation current includes a first current to maintain the rotor's radial levitation and a second current to maintain the rotor's axial levitation.

[0049] The foregoing Figure 3 In the corresponding embodiment, the specific structure of the current detection circuit is as follows: Figure 4 As shown, based on this, see Figure 4 , Figure 4 A schematic diagram of a current detection circuit provided in this application embodiment includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, a second capacitor C2, and an operational amplifier U1, wherein:

[0050] One end of the first resistor R1 is connected to the first voltage acquisition port of the motor drive module, and the other end is connected to the inverting input terminal of the operational amplifier U1. The other end of the first resistor R1 is also connected to one end of the third resistor R3.

[0051] One end of the second resistor R2 is connected to the second voltage acquisition port of the motor drive module, and the other end is connected to the non-inverting input of the operational amplifier U1. The other end of the second resistor R2 is also connected to one end of the fourth resistor R4.

[0052] The inverting input terminal of operational amplifier U1 is also connected to one end of the first capacitor C1, and the other end of the first capacitor C1 is grounded; the non-inverting input terminal of operational amplifier U1 is also connected to one end of the second capacitor C2, and the other end of the second capacitor C2 is grounded; the output terminal of operational amplifier U1 is connected to one end of the fifth resistor R5, and the other end of the fifth resistor R5 serves as the output port; the output terminal of operational amplifier U1 is also connected to the other end of the third resistor R3.

[0053] In one embodiment of this application, the first resistor R1 and the second resistor R2 have the same resistance value, and the resistance values ​​of the first resistor R1 and the second resistor R2 are between [4kΩ, 6kΩ]. For example, the resistance values ​​of the first resistor R1 and the second resistor R2 can be 4kΩ, 5kΩ, and 6kΩ.

[0054] In one embodiment of this application, the resistance of the third resistor R3 is between [9kΩ, 11kΩ], for example, the resistance of the third resistor R3 can be 9kΩ, 10kΩ, or 11kΩ. The resistance of the fourth resistor R4 is between [9kΩ, 11kΩ], for example, the resistance of the fourth resistor R4 can be 9kΩ, 10kΩ, or 11kΩ. The resistance of the fifth resistor R5 is between [9kΩ, 11kΩ], for example, the resistance of the fifth resistor R5 can be 9kΩ, 10kΩ, or 11kΩ.

[0055] In one embodiment of this application, the first capacitor C1 and the second capacitor C2 have the same capacitance value, which is between [0.05uF, 0.15uF]. For example, the capacitance values ​​of the first capacitor C1 and the second capacitor C2 are 0.05uF, 0.1uF, and 0.15uF, respectively.

[0056] The foregoing Figure 3 In the corresponding embodiment, the specific structure of the rotor position detection circuit is as follows: Figure 5 As shown, based on this, see Figure 5 , Figure 5 This is a schematic diagram of a rotor position detection circuit provided in an embodiment of this application. The rotor position detection circuit includes a Hall sensor U2, a sixth resistor R6, a third capacitor C3, and a fourth capacitor C4, wherein:

[0057] The VCC interface of Hall sensor U2 is connected to one end of the third capacitor C3 and the VREF interface, respectively, and the other end of the third capacitor C3 is grounded; the OUT interface of Hall sensor U2 is connected to one end of the fourth capacitor C4, and the other end of the fourth capacitor C4 is connected to the sixth resistor R6, which is grounded; the GND interface of Hall sensor U2 is grounded; the #SLEEP interface of Hall sensor U2 is connected to the VREF interface.

[0058] In one embodiment of this application, the capacitance value of the third capacitor C3 is between [90nF, 110nF], for example, the capacitance value of the third capacitor C3 is 90nF, 100nF, and 110nF; the capacitance value of the fourth capacitor C4 is between [90nF, 110nF], for example, the capacitance value of the fourth capacitor C4 is 90nF, 100nF, and 110nF; and the resistance value of the sixth resistor R6 is between [9kΩ, 11kΩ], for example, the resistance value of the sixth resistor R6 is 9kΩ, 10kΩ, and 11kΩ.

[0059] The above description is merely a preferred embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the scope of protection of this application.

Claims

1. A magnetic levitation motor system for an implantable magnetic levitation blood pump, characterized in that, The magnetic levitation motor system includes a magnetic levitation motor and motor control equipment, wherein: The magnetic levitation motor includes an electromagnetic coil and a rotor. The rotor achieves levitation and rotation through the electromagnetic force between itself and the electromagnetic coil, thus realizing the operation of the magnetic levitation motor. The motor control device integrates a motor control motherboard, which controls the operation of the magnetic levitation motor. The motor control motherboard integrates a central control module, a motor drive module, and a closed-loop feedback module. The closed-loop feedback module detects the rotor's levitation offset data and actual operating current, and feeds this data back to the central control module through a dual closed-loop feedback mechanism. The central control module uses the levitation offset data and actual operating current, employing a built-in control algorithm, to generate a pulse width modulation (PWM) control signal. The motor drive module converts the PWM control signal into a levitation current and a rotational current. The levitation current includes a first current that maintains the rotor's radial levitation and a second current that maintains the rotor's axial levitation. The levitation current and rotational current are used to adjust the current in the electromagnetic coil to maintain the rotor's levitation and rotation.

2. The system according to claim 1, characterized in that, The closed-loop feedback module includes a rotor position detection circuit and a current detection circuit. The input end of the rotor position detection circuit is connected to the rotor, and the output end is connected to the first interface of the central control module. The input end of the current detection circuit is connected to the motor drive module, and the output end is connected to the second interface of the central control module. The rotor position detection circuit detects the rotor's suspension offset data, and the current detection circuit detects the rotor's actual operating current.

3. The system according to claim 2, characterized in that, The current detection circuit includes a first resistor (R1), a second resistor (R2), a third resistor (R3), a fourth resistor (R4), a fifth resistor (R5), a first capacitor (C1), a second capacitor (C2), and an operational amplifier (U1), wherein: One end of the first resistor (R1) is connected to the first voltage acquisition port of the motor drive module, and the other end is connected to the inverting input terminal of the operational amplifier (U1). The other end of the first resistor (R1) is also connected to one end of the third resistor (R3). One end of the second resistor (R2) is connected to the second voltage acquisition port of the motor drive module, and the other end is connected to the non-inverting input terminal of the operational amplifier (U1). The other end of the second resistor (R2) is also connected to one end of the fourth resistor (R4). The inverting input terminal of the operational amplifier (U1) is also connected to one end of the first capacitor (C1), and the other end of the first capacitor (C1) is grounded. The non-inverting input terminal of the operational amplifier (U1) is also connected to one end of the second capacitor (C2), and the other end of the second capacitor (C2) is grounded; The output terminal of the operational amplifier (U1) is connected to one end of the fifth resistor (R5), and the other end of the fifth resistor (R5) serves as the output port. The output terminal of the operational amplifier (U1) is also connected to the other end of the third resistor (R3).

4. The system according to claim 3, characterized in that, The first resistor (R1) and the second resistor (R2) have the same resistance value. The resistance values ​​of the first resistor (R1) and the second resistor (R2) are between [4kΩ and 6kΩ]. The resistance value of the third resistor (R3) is between [9kΩ and 11kΩ]. The resistance value of the fourth resistor (R4) is between [9kΩ and 11kΩ]. The resistance value of the fifth resistor (R5) is between [9kΩ and 11kΩ].

5. The system according to claim 4, characterized in that, The first capacitor (C1) and the second capacitor (C2) have the same capacitance value, which is between [0.05uF and 0.15uF].

6. The system according to any one of claims 2-5, characterized in that, The rotor position detection circuit includes a Hall sensor (U2), a sixth resistor (R6), a third capacitor (C3), and a fourth capacitor (C4), wherein: The VCC interface of the Hall sensor (U2) is connected to one end of the third capacitor (C3) and the VREF interface, respectively, and the other end of the third capacitor (C3) is grounded; the OUT interface of the Hall sensor (U2) is connected to one end of the fourth capacitor (C4), and the other end of the fourth capacitor (C4) is connected to the sixth resistor (R6), which is grounded; the GND interface of the Hall sensor (U2) is grounded; and the #SLEEP interface of the Hall sensor (U2) is connected to the VREF interface.

7. The system according to claim 6, characterized in that, The capacitance value of the third capacitor (C3) is between [90nF and 110nF], the capacitance value of the fourth capacitor (C4) is between [90nF and 110nF], and the resistance value of the sixth resistor (R6) is between [9kΩ and 11kΩ].

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