Rotational speed control device and method, ventricular assist system, storage medium and apparatus

Abstract

The application discloses a rotating speed control device and method, a ventricular assist system, a storage medium and equipment. The rotating speed control device is used for obtaining a target rotating speed of a motor; obtaining a rotating speed value of the motor and a flow value of a pump; outputting a control instruction to the motor according to the target rotating speed, the rotating speed value, the flow value and a preset feedback control law, so as to control the motor to drive the pump to deliver blood at a corresponding rotating speed; the feedback control law is created according to a first correlation model of the motor and the pump and a second correlation model of the pump and a human body, and rotating speed feedback control gain and flow feedback control gain in the feedback control law are obtained according to Lyapunov theory. The application can improve the reliability and accuracy of the feedback control gain, and can also stabilize the rotating speed at the target rotating speed, and the rotating speed is not affected by pressure changes in a systole period and a diastole period.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices for heart surgery, in particular to a rotational speed control device and method, a ventricular assist system, a storage medium and equipment. BACKGROUND

[0002] LVAD (left ventricular assist device) is a left heart assist device. Left heart assist is to introduce blood flow from the left atrium or left ventricle into an auxiliary pump body, drive the blood flow into the aorta through the pump, and completely replace the left heart pumping function. LVAD can ensure that the cardiac output and perfusion pressure of heart failure patients remain within a certain physiological range by adjusting the rotational speed.

[0003] In the rotational speed control process based on LVAD, the PID (proportional-integral-derivative) control of the sampling rotational speed is usually used. The disadvantage of this method is that the selection of the PID parameters needs to rely on experience debugging, and because the heart is always in the alternating state of the systole and diastole, the pressure difference at both ends of the pump is always changing, so that the rotational speed will always fluctuate around the target rotational speed and is not stable. SUMMARY

[0004] The present application provides a rotational speed control device and method, a ventricular assist system, a storage medium and equipment, which are used to solve the problems of inaccurate PID parameters selected by experience and the fluctuation of the rotational speed around the target rotational speed caused by the change of the pressure difference at both ends of the pump. The technical solution is as follows:

[0005] In a first aspect, a rotational speed control device is provided,

[0006] The rotational speed control device is configured to obtain a target rotational speed of a motor.

[0007] The rotational speed control device is further configured to obtain a rotational speed value of the motor and a flow value of the pump.

[0008] The rotational speed control device is further configured to output a control instruction to the motor according to the target rotational speed, the rotational speed value, the flow value and a preset feedback control law, and the control instruction is used to control the motor to drive the pump to deliver blood at a corresponding rotational speed.

[0009] The feedback control law is created according to a first association model of the motor and the pump and a second association model of the pump and the human body, and the rotational speed feedback control gain and the flow feedback control gain in the feedback control law are obtained according to the Lyapunov theory.

[0010] In a second aspect, a ventricular assist system is provided, which comprises a motor speed acquisition module, a flow acquisition module, a motor, a pump, and a speed control device as described above.

[0011] The motor speed acquisition module is configured to acquire a speed value of the motor and output the speed value to the speed control device.

[0012] The flow acquisition module is configured to acquire a flow value of the pump and output the flow value to the speed control device.

[0013] The speed control device is configured to acquire a target speed of the motor, and output a control instruction to the motor according to the target speed, the speed value, the flow value, and a preset feedback control law.

[0014] The motor is configured to drive the pump to deliver blood at a speed corresponding to the control instruction.

[0015] In a third aspect, a speed control method for a ventricular assist system is provided, which is used in a speed control device as described above, and the method comprises the following steps:

[0016] Acquiring a target speed of the motor;

[0017] Acquiring a speed value of the motor and a flow value of the pump;

[0018] Outputting a control instruction to the motor according to the target speed, the speed value, the flow value, and a preset feedback control law, the control instruction being used to control the motor to drive the pump to deliver blood at a corresponding speed;

[0019] The feedback control law is created according to a first association model of the motor and the pump and a second association model of the pump and a human body, and the speed feedback control gain and the flow feedback control gain in the feedback control law are obtained according to Lyapunov theory.

[0020] In a fourth aspect, a computer readable storage medium is provided, which stores at least one instruction, the at least one instruction being loaded and executed by a processor to implement the speed control method as described above.

[0021] In a fifth aspect, an electronic device is provided, which comprises a processor and a memory, the memory storing at least one instruction, the instruction being loaded and executed by the processor to implement the speed control method as described above.

[0022] The technical scheme provided in the application has at least the following beneficial effects:

[0023] Since the heart is always in the state of alternation of systole and diastole, the pressure difference of both ends of the pump is always changing, and the flow can indirectly reflect the change of the pressure difference, so the speed of the motor can be controlled by coupling the speed and the flow to offset the influence of the systole and diastole of the heart; then, the different conditions required to be met by the speed feedback control gain and the flow feedback control gain in the systole and diastole of the heart can be derived through the stable condition of the Lyapunov function, which provides an explicit selection method for the speed feedback control gain and the flow feedback control gain, and compared with the selection method through experience debugging, the reliability and accuracy of the speed feedback control gain and the flow feedback control gain can be improved.

[0024] On the basis of the target speed, the speed of the motor can be controlled according to the feedback of the speed value and the flow value, so that the speed is more stable and smooth in the steady state, and is not affected by the pressure change in the systole and diastole. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0026] Figure 1 is a schematic diagram of the derivation process of the feedback control law provided by an embodiment of the present application;

[0027] Figure 2 is a schematic diagram of blood circulation provided by an embodiment of the present application;

[0028] Figure 3 is a schematic diagram of the control process of the speed control method provided by an embodiment of the present application;

[0029] Figure 4 is a schematic diagram of the structure of the ventricular assist system provided by an embodiment of the present application. DETAILED DESCRIPTION

[0030] The exemplary embodiments of the present application are described below with reference to the accompanying drawings, which include various details of the embodiments of the present application to help understanding, and should be considered as merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Also, in order to be clear and concise, the description in the following description omits the description of well-known functions and structures.

[0031] Because the heart is always in the state of alternation of systole and diastole, which leads to the fact that the pressure difference of both ends of the pump is always changing. If only the speed of the motor is controlled by the feedback of the speed and the target speed, the actual speed will fluctuate around the target speed and cannot be stabilized at the target speed.

[0032] We find that the flow can indirectly reflect the change of the pressure difference, so we use the coupling of the speed and the flow to control the speed of the motor to offset the influence of the systole and diastole of the heart. Then, through the Lyapunov theory, we can deduce different conditions that the speed feedback control gain and the flow feedback control gain in the feedback control law need to meet in the systole and diastole of the heart, which provides an explicit selection method for the speed feedback control gain and the flow feedback control gain. Compared with the selection method through experience debugging, the reliability and accuracy of the speed feedback control gain and the flow feedback control gain can be improved. In addition, on the basis of the target speed, the speed of the motor can be controlled according to the feedback of the speed value of the motor and the flow value of the pump, so that the speed is more stable and smooth in the steady state and is not affected by the pressure change in the systole and diastole.

[0033] In one embodiment, the feedback control law is created according to the first associated model of the motor and the pump and the second associated model of the pump and the human body, and the speed feedback control gain and the flow feedback control gain in the feedback control law are obtained according to the Lyapunov theory. As shown in Figure 1 The derivation process of the feedback control law can include a model creation step 110, a law creation step 120, and a gain calculation step 130.

[0034] The model creation step 110 specifically creates the associated model of the motor and the pump and the associated model of the pump and the human body, and obtains the coupled system model.

[0035] In this embodiment, the motor, the pump, and the human body need to be coupled modeled. Specifically, the first associated model of the motor and the pump and the second associated model of the pump and the human body can be created, and the two associated models are combined to obtain the coupled system model. The first associated model of the motor and the pump is created based on the association between the load torque of the motor and the pump, and the second associated model of the pump and the human body is created based on the association between the pump and the pressure difference at both ends. Here, the pressure difference refers to the difference between the aortic pressure and the left ventricular pressure.

[0036] In one embodiment, the first associated model of the motor and the pump is created by the following steps:

[0037] (1) Obtain the torque characteristic model of the motor as J is the moment of inertia of the motor, T e is the torque of the motor, B is the damping coefficient, w is the speed of the motor, and T p is the load torque.

[0038] (2) Obtain the motor torque as T K b is the motor back electromotive force constant, and I is the current.

[0039] (3) Obtain the load torque as T p = a1w 3 + a2f(F, w), a1 and a2 are constant coefficients, F is the flow of the pump, and f(F, w) is a self-defined model related to F and w.

[0040] where f(F, w) is a model defined according to business requirements, and its specific form is not limited in the embodiment. In some examples, f(F, w) can be Fw 2 , or f(F, w) can be F 2 w 2 , or f(F, w) can also be F 3 w 2 , etc.

[0041] Taking f(F, w) as Fw 2 for example, the load torque is T p = a1w 3 + a2Fw 2 .

[0042] (4) Input the motor torque and the load torque into the torque characteristic model to obtain the first association model of the motor and the pump as

[0043] After inputting the motor torque and the load torque into the torque characteristic model, a simple formula transformation can be performed, that is, multiply J on both sides of the equal sign to obtain the first association model of the motor and the pump as That is, the first association model is obtained by inputting the motor torque and the load torque into the torque characteristic model of the motor.

[0044] Taking f(F, w) as Fw 2 for example, the first association model of the motor and the pump is

[0045] In an embodiment, the association model of the pump and the human body is created by the following steps:

[0046] (1) Obtain the hydraulic characteristic model of the pump as b0, b1 and b2 are constant coefficients, and ΔP is the pressure difference between the two ends of the pump.

[0047] (2) Obtain the pressure difference as ΔP = P A -P L , P A is the aortic pressure, and PL is the left ventricular pressure.

[0048] Since the pump is installed between the left ventricle and the aorta as a ventricular assist device, the pressure difference is ΔP = P A -P L , which represents the coupling of the pump and the human body.

[0049] (3) The pressure difference is input into the hydraulic characteristic model to obtain a second correlation model of the pump and the human body as That is, the second correlation model is obtained by inputting the pressure difference at both ends of the pump into the hydraulic characteristic model of the pump.

[0050] As shown in Figure 2 , in combination with the principle of blood circulation of the human body, the created coupling system model is:

[0051]

[0052] wherein v = [v1, v2, …v n ] T is the pressure in each cavity of the human body, v5 is the aortic pressure (same meaning as P A ), v4 is the left ventricular pressure (same meaning as P L ), z is the flow of the pump (same meaning as F), w is the motor speed. Let x = [v, z, w] T , g(x) is a nonlinear term, then the coupling system model can be written as a whole:

[0053] For example, f(F, w) is Fw 2 , then the coupling system model is

[0054] The feedback control law with unknown parameters is created according to the coupling system model, and the feedback control law represents the correlation between the input current and the speed of the motor, and the unknown parameters include the speed feedback control gain and the flow feedback control gain.

[0055] In one embodiment, the feedback control law with unknown parameters is created by the following steps:

[0056] (1) According to the coupling system model, the dependent variable of the feedback control law is the current I, and the independent variables include the motor speed w, the target speed w set , the gear basic current I set of the motor, and the flow F of the pump. Among them, the gear basic current I set is the steady-state current required by the preset target gear.

[0057] (2) According to the current I, the motor speed w, the target speed w set , the gear basic current I set of the motor, and the flow F of the pump, the feedback control law with unknown parameters is created.set , Gear base current I set The feedback control law with unknown parameters, based on the pump flow rate F, is I(t) = K1(w(t) - w set (t))+K2(f(F,w)-f(F,w set ))+I set K1 is an unknown speed feedback control gain, and K2 is an unknown flow feedback control gain.

[0058] Let f(F, w) be Fw 2 For example, the feedback control law with unknown parameters is as follows: K1 and K2 are unknown parameters. We need to solve for K1 and K2 based on the stability conditions of the Lyapunov function.

[0059] In this embodiment, the speed feedback control gain and flow feedback control gain are obtained based on the system stability condition that the derivative of the Lyapunov function is less than or equal to zero.

[0060] The gain calculation step 130 specifically calculates the speed feedback control gain and flow feedback control gain based on the stability condition of the Lyapunov function. The speed feedback control gain includes the diastolic gain corresponding to the heart being in diastole and the systolic gain corresponding to the heart being in systole.

[0061] In one embodiment, the speed feedback control gain and flow feedback control gain are specifically solved through the following steps:

[0062] (1) Obtain the Lyapunov function as V = (ww set ) T P(ww set ), where P is a positive definite matrix. The Lyapunov function is the energy function representing the error between the motor speed and the target speed.

[0063] (2) Calculate the derivative of the Lyapunov function as follows:

[0064] (3) Input the derivative with I, and obtain in,

[0065] In the known first correlation model between the motor and the pump and I(t)=K1(w(t)-w set (t))+K2(f(F,w)-f(F,w set ))+I set Under the premise that the current I can be input into the first correlation model of the motor and the pump, the third correlation model can be obtained. That is, the third correlation model is obtained by inputting the feedback control law into the first correlation model.

[0066] w set In the third correlation model, the fourth correlation model is obtained by inputting the target speed. That is, the fourth correlation model is obtained by inputting the target speed into the third correlation model.

[0067] The third correlation model and the fourth correlation model are input into the derivative to obtain:

[0068]

[0069]

[0070] That is, the coefficient is generated by inputting the third correlation model and the fourth correlation model into the derivative of the Lyapunov function.

[0071] (4) The stability condition of the Lyapunov function is determined according to the stability condition of the Lyapunov function. Need to be less than or equal to 0.

[0072] When That is, when the derivative of the Lyapunov function is less than or equal to 0, according to the Lyapunov theory, the system is asymptotically stable, so the conditions that the speed feedback control gain and the flow feedback control gain need to satisfy can be derived as Less than or equal to 0.

[0073] (5) When Less than or equal to 0, the speed feedback control gain and the flow feedback control gain are calculated.

[0074] The coefficient includes the motor speed, the target speed, the feedback control gain, and the flow control gain, and the feedback control gain and the flow control gain are determined based on the boundary conditions to satisfy the correlation between the motor speed and the target speed, and then determined based on the correlation; wherein the boundary conditions are generated based on the characteristics of the pump in the diastolic and systolic periods.

[0075] Specifically, the boundary conditions can include the following three kinds:

[0076] (1) The motor is prohibited to reverse, so it can be deduced that the motor speed and the target speed are both ≥0.

[0077] Specifically, since the pump exists, the motor cannot be reversed, so the motor speed w≥0; at the same time, we set the target speed w set ≥0, then it can be deduced that Always true;

[0078] (2) When the heart is in the systolic period, the pump is rotating forward.

[0079] When the heart is in systole, blood flows from the left ventricle to the aorta, at this time the pump is rotating forward, and the rotating speed w of the pump is obtained by experiment test 2 The minimum increment of w is

[0080] (3) When the heart is in diastole, the minimum rotating speed of the pump is 0.

[0081] When the heart is in diastole, the valve is closed, and the minimum rotating speed of the pump is 0; it can be deduced that is always true.

[0082] Therefore, it can be obtained that

[0083]

[0084] where, when diastole when systole

[0085] Take that is is true. Taking f(F, w) as Fw 2 for example, it is true that

[0086] It can be deduced that when the rotating speed feedback control gain is represents the diastole gain, represents the systole gain; the flow feedback control gain is

[0087] In this embodiment, the rotating speed feedback control gain and the flow feedback control gain also need to be input into the feedback control law to obtain the final feedback control law, at this time, all the parameters in the feedback control law are known parameters.

[0088] Specifically, the diastole gain and the flow feedback control gain are input into the feedback control law with unknown parameters to obtain the feedback control law of diastole as The systole gain and the flow feedback control gain are input into the feedback control law with unknown parameters to obtain the feedback control law of systole as

[0089] Taking f(F, w) as Fw 2 for example, the feedback control law of diastole is the feedback control law of systole is

[0090] After obtaining the feedback control law, the feedback control law can be configured in the rotating speed control device in advance, and then the rotating speed control device is used to control the motor, and the pump is driven to work by the motor. The following will be combined​​Figure 3 The control flow of the rotation speed control device is described.

[0091] In step 301, the target rotation speed of the motor is obtained.

[0092] The target rotation speed of the motor is a pre-set rotation speed, and is also the rotation speed that the motor finally reaches.

[0093] There are many ways to set the target rotation speed, for example, the specific value of the target rotation speed can be input, or the target rotation speed can also be set through gears.

[0094] Taking the target rotation speed set through gears as an example, at least two gears are set in the rotation speed control device, and different gears correspond to different target rotation speeds. The user can select the gear according to the demand. After the user selects a gear, the rotation speed control device obtains the target rotation speed corresponding to the gear.

[0095] When the target rotation speed is set through gears, the rotation speed control device also needs to obtain the gear basic current of the gear selected by the user.

[0096] In step 302, the rotation speed value of the motor and the flow value of the pump are obtained.

[0097] The rotation speed value represents the current rotation speed of the motor. The rotation speed value can be an actual value, for example, obtained by sampling the rotation speed of the motor through a motor rotation speed sensor, or the rotation speed value can also be an analog value, for example, obtained by estimating the rotation speed of the motor through a motor rotation speed simulation model.

[0098] The flow value represents the current flow of the pump. The flow value can be an actual value, for example, obtained by sampling the flow of the pump through a flow sensor, or the flow value can also be an analog value, for example, obtained by estimating the flow of the pump through a flow simulation model.

[0099] Taking the rotation speed value and the flow value as actual values as an example, the ventricular assist system at least includes a motor rotation speed sensor and a flow sensor. The motor rotation speed sensor is used to sample the rotation speed of the motor to obtain the rotation speed value. The flow sensor is used to sample the flow of the pump to obtain the flow value. The sampling frequency of the motor rotation speed sensor and the flow sensor can be set according to the business demand, which is not limited in the embodiment.

[0100] In step 303, a control instruction is output to the motor according to the target rotation speed, the rotation speed value, the flow value, and a pre-set feedback control law. The control instruction is used to control the motor to drive the pump to deliver blood at a corresponding rotation speed.

[0101] When the target rotation speed is set through gears, the rotation speed control device also needs to obtain the gear basic current, and output a control instruction to the motor according to the target rotation speed, the rotation speed value, the flow value, the gear basic current, and a pre-set feedback control law.

[0102] In this embodiment, the rotational speed feedback control gain includes a diastolic phase gain and a systolic phase gain. The feedback control law in the diastolic phase is equal to a first product The second product The sum of the gear basic current and the first product is equal to the difference between the time-domain expression w(t) of the motor rotational speed and the time-domain expression w(t) of the target rotational speed multiplied by the diastolic phase gain set The second product is equal to the difference between the first custom model f(F, w) and the second custom model f(F, w) multiplied by the flow feedback control gain set The first custom model is a custom model related to the flow and the motor rotational speed, and the second custom model is a custom model related to the flow and the target rotational speed.

[0103] The feedback control law in the systolic phase is equal to a third product The second product The sum of the gear basic current and the third product is equal to the difference between the time-domain expression w(t) of the motor rotational speed and the time-domain expression w(t) of the target rotational speed multiplied by the systolic phase gain set

[0104] When calculating the control instruction based on the feedback control law, when the heart is in the diastolic phase, the rotational speed control device obtains the feedback control law in the diastolic phase, and outputs a control instruction in the diastolic phase to the motor according to the target rotational speed, the rotational speed value, the flow value, and the feedback control law in the diastolic phase. The control instruction in the diastolic phase is used to control the motor to drive the pump to transport blood at a corresponding rotational speed in the diastolic phase. When the heart is in the systolic phase, the rotational speed control device obtains the feedback control law in the systolic phase, and outputs a control instruction in the systolic phase to the motor according to the target rotational speed, the rotational speed value, the flow value, and the feedback control law in the systolic phase. The control instruction in the systolic phase is used to control the motor to drive the pump to transport blood at a corresponding rotational speed in the systolic phase.

[0105] When the motor is controlled by the current, the rotational speed control device can calculate the current size of the output current based on the feedback control law after receiving the rotational speed value and the flow value and obtaining the target rotational speed, and output a current of the corresponding size to the motor. The motor determines the corresponding rotational speed according to the received current, and drives the pump at the rotational speed, so as to introduce the blood in the left ventricle into the pump and drive the blood in the pump into the aorta.

[0106] In this embodiment, the rotational speed control device can control the motor rotational speed w to the target rotational speed w set , so that the rotational speed w is more stable and smooth in the steady state, and is not affected by the pressure changes in the systolic phase and the diastolic phase.​​​

[0107] In summary, the rotating speed control device provided by the embodiments of the present application can be used to control the rotating speed of the motor by coupling the rotating speed and the flow rate, so as to offset the influence of the contraction and relaxation of the heart, because the heart is always in the alternating state of the contraction period and the relaxation period, which leads to the change of the pressure difference at both ends of the pump, and the flow rate can indirectly reflect the change of the pressure difference. Then, the stable conditions of the Lyapunov function can be used to derive different conditions required by the rotating speed feedback control gain and the flow rate feedback control gain in the contraction period and the relaxation period of the heart, so as to provide an explicit selection method for the rotating speed feedback control gain and the flow rate feedback control gain, and compared with the selection method by experience, the reliability and accuracy of the rotating speed feedback control gain and the flow rate feedback control gain can be improved.

[0108] On the basis of the target rotating speed, the rotating speed of the motor can be controlled according to the feedback of the rotating speed value and the flow rate value, so that the rotating speed is more stable and smooth in the steady state and is not affected by the pressure change in the contraction period and the relaxation period.

[0109] Please refer to Figure 4 which shows a system block diagram of a ventricular assist system provided by an embodiment of the present application, which can include a rotating speed control device 100, a motor rotating speed acquisition module (not shown in the figure), a flow rate acquisition module (not shown in the figure), a motor 200 and a pump 300 as shown in Figure 1 .

[0110] The motor rotating speed acquisition module is configured to acquire the rotating speed value of the motor 200 and output the rotating speed value to the rotating speed control device 100.

[0111] The flow rate acquisition module is configured to acquire the flow rate value of the pump 300 and output the flow rate value to the rotating speed control device 100.

[0112] The rotating speed value represents the current rotating speed of the motor. The rotating speed value can be an actual value, for example, when the motor rotating speed acquisition module is a motor rotating speed sensor, the rotating speed of the motor is sampled by the motor rotating speed sensor to obtain the actual value, or the rotating speed value can be an analog value, for example, when the motor rotating speed acquisition module is a motor rotating speed analog model, the rotating speed of the motor is estimated by the motor rotating speed analog model to obtain the analog value.

[0113] The flow rate value represents the current flow rate of the pump. The flow rate value can be an actual value, for example, when the flow rate acquisition module is a flow rate sensor, the flow rate of the pump is sampled by the flow rate sensor to obtain the actual value, or the flow rate value can be an analog value, for example, when the flow rate acquisition module is a flow rate analog model, the flow rate of the pump is estimated by the flow rate analog model to obtain the analog value.

[0114] The motor speed value and the flow value are actual values, and the motor speed acquisition module is a motor speed sensor, and the flow acquisition module is a flow sensor. The ventricular assist system at least includes the motor speed sensor and the flow sensor. The motor speed sensor is used for sampling the speed of the motor 200 to obtain the speed value. The flow sensor is used for sampling the flow of the pump 300 to obtain the flow value. The sampling frequency of the motor speed sensor and the flow sensor can be set according to business requirements, which is not limited in the embodiment.

[0115] The speed control device 100 is used for acquiring a target speed of the motor, and outputting a control instruction to the motor according to the target speed, the speed value, the flow value, and a preset feedback control law.

[0116] The target speed of the motor is a preset speed, which is also the final speed to be reached by the motor.

[0117] There are many ways to set the target speed, for example, the specific value of the target speed can be input, or the target speed can also be set through gears.

[0118] Taking the target speed set through gears as an example, at least two gears are set in the speed control device 100, and different gears correspond to different target speeds. The user can select gears according to requirements. After the user selects a gear, the speed control device 100 acquires the target speed corresponding to the gear.

[0119] When the target speed is set through gears, the speed control device 100 also needs to acquire the gear basic current of the selected gear.

[0120] When the motor 200 is current-controlled, the speed control device 100 can calculate the current size of the output current based on the feedback control law after acquiring the speed value and the flow value, and acquiring the target speed and the gear basic current, and outputs the current of the corresponding size to the motor.

[0121] The motor 200 is used for driving the pump 300 to transport blood according to the speed corresponding to the control instruction.

[0122] When the control instruction is a current, the motor 200 determines the corresponding speed according to the received current, and drives the pump 300 at the speed, so as to introduce the blood of the left ventricle into the pump 300, and drive the blood to enter the aorta through the pump 300.

[0123] In an embodiment, the ventricular assist system can be regarded as a left ventricular assist device LVAD.

[0124] An embodiment of the present application provides a computer readable storage medium, the storage medium stores at least one instruction, the at least one instruction is loaded and executed by a processor to realize the speed control method as described above.

[0125] An embodiment of the present application provides an electronic device, which comprises a processor and a memory, the memory storing at least one instruction, the instruction being loaded and executed by the processor to implement the rotating speed control method as described above.

[0126] Those skilled in the art can understand that all or part of the steps of the above-mentioned embodiments can be completed by hardware, or can be instructed by a program to complete the related hardware, and the program can be stored in a computer readable storage medium, and the storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk.

[0127] The above description is not intended to limit the embodiments of the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of the present application shall be included in the protection scope of the embodiments of the present application.

Claims

1. A rotating speed control device for a ventricular assist system, the rotating speed control device comprising: a target rotating speed of a motor is obtained; a rotating speed value of the motor and a flow value of a pump are obtained; a control instruction is outputted to the motor according to the target rotating speed, the rotating speed value, the flow value and a preset feedback control law, the control instruction being used to control the motor to drive the pump to deliver blood at a corresponding rotating speed; the feedback control law is created according to a first correlation model of the motor and the pump and a second correlation model of the pump and a human body, and rotating speed feedback control gain and flow feedback control gain in the feedback control law are obtained according to Lyapunov theory, the rotating speed feedback control gain and the flow feedback control gain being obtained based on a system stability condition that a derivative of a Lyapunov function is less than or equal to zero, the Lyapunov function being an energy function representing an error between the rotating speed of the motor and the target rotating speed; the first correlation model is obtained by inputting motor torque and load torque into a torque characteristic model of the motor, the load torque including a self-defined model related to the flow of the pump and the rotating speed of the motor; the second correlation model is obtained by inputting a pressure difference between two ends of the pump into a hydraulic characteristic model of the pump.

2. The rotation speed control device according to claim 1, characterized by coefficients of the derivative of the Lyapunov function are generated by inputting a third correlation model and a fourth correlation model into the derivative of the Lyapunov function, the third correlation model being obtained by inputting the feedback control law into the first correlation model, and the fourth correlation model being obtained by inputting the target rotating speed into the third correlation model.

3. The rotation speed control device according to claim 1, characterized by the coefficients of the derivative of the Lyapunov function include the rotating speed of the motor, the target rotating speed, the rotating speed feedback control gain and the flow feedback control gain, and the rotating speed feedback control gain and the flow feedback control gain are determined based on a correlation relationship between the rotating speed of the motor and the target rotating speed satisfying a boundary condition and then based on the correlation relationship; 4. The rotational speed control device according to any one of claims 1 to 3, characterized by the rotating speed control device further comprises: a feedback control law in a diastolic phase is obtained, and a control instruction in the diastolic phase is outputted to the motor according to the target rotating speed, the rotating speed value, the flow value and the feedback control law in the diastolic phase, the control instruction in the diastolic phase being used to control the motor to drive the pump to deliver blood at a corresponding rotating speed in the diastolic phase; a feedback control law in a systolic phase is obtained, and a control instruction in the systolic phase is outputted to the motor according to the target rotating speed, the rotating speed value, the flow value and the feedback control law in the systolic phase, the control instruction in the systolic phase being used to control the motor to drive the pump to deliver blood at a corresponding rotating speed in the systolic phase.

5. The rotation speed control device according to claim 4, characterized by the rotating speed feedback control gain includes a diastolic phase gain and a systolic phase gain, and the diastolic phase gain corresponds to a boundary condition that the motor is prohibited from being reversed and the lowest rotating speed of the pump is zero when the heart is in the diastolic phase. The boundary condition corresponding to the systolic gain is that the motor is prohibited from reversing, and the pump is rotating forward when the heart is in the systolic phase.

6. A ventricular assist system, characterized by The ventricular assist system comprises a motor speed acquisition module, a flow acquisition module, a motor, a pump and the speed control device according to any one of claims 1 to 5. The motor speed acquisition module is configured to acquire a speed value of the motor and output the speed value to the speed control device. The flow acquisition module is configured to acquire a flow value of the pump and output the flow value to the speed control device. The speed control device is configured to acquire a target speed of the motor, and output a control instruction to the motor according to the target speed, the speed value, the flow value and a preset feedback control law. The motor is configured to drive the pump to deliver blood at a speed corresponding to the control instruction.

7. A computer readable storage medium characterized in that, The storage medium stores at least one instruction, which is loaded and executed by the processor to perform the following speed control method: acquire a target speed of the motor; acquire a speed value of the motor and a flow value of the pump; output a control instruction to the motor according to the target speed, the speed value, the flow value and a preset feedback control law, the control instruction being used to control the motor to drive the pump to deliver blood at a corresponding speed; The feedback control law is created according to a first association model of the motor and the pump and a second association model of the pump and the human body, and the speed feedback control gain and the flow feedback control gain in the feedback control law are obtained according to Lyapunov theory, the speed feedback control gain and the flow feedback control gain being obtained based on a system stability condition that a derivative of a Lyapunov function is less than or equal to zero, the Lyapunov function being an energy function representing an error between the speed of the motor and the target speed; The first association model is obtained by inputting motor torque and load torque into a torque characteristic model of the motor, the load torque comprising a self-defined model related to the flow of the pump and the speed of the motor; The second association model is obtained by inputting a pressure difference between two ends of the pump into a hydraulic characteristic model of the pump.

8. An electronic device, comprising: The electronic device comprises a processor and a memory, the memory storing at least one instruction, which is loaded and executed by the processor to perform the following speed control method: acquire a target speed of the motor; acquire a speed value of the motor and a flow value of the pump; output a control instruction to the motor according to the target speed, the speed value, the flow value and a preset feedback control law, the control instruction being used to control the motor to drive the pump to deliver blood at a corresponding speed; The feedback control law is created according to a first correlation model of the motor and the pump and a second correlation model of the pump and the human body, and a rotating speed feedback control gain and a flow feedback control gain in the feedback control law are obtained according to Lyapunov theory, the rotating speed feedback control gain and the flow feedback control gain are obtained based on a system stability condition that a derivative of a Lyapunov function is less than or equal to zero, and the Lyapunov function is an energy function representing an error between the rotating speed of the motor and the target rotating speed; The first correlation model is obtained by inputting motor torque and load torque into a torque characteristic model of the motor, and the load torque comprises a self-defined model related to the flow of the pump and the rotating speed of the motor; The second correlation model is obtained by inputting a pressure difference between two ends of the pump into a water conservancy characteristic model of the pump.

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