A control device, ventricular assist system and adaptive control method

Abstract

The present invention relates to a control device, a ventricular assist system and an adaptive control method, which are intended to estimate the current flow of an LVAD based on the current current, calculate the target flow based on a flow preset value and heart rate compensation, and perform feedback adjustment to achieve adaptive changes in the current flow of the LVAD following changes in the heart rate; further, a target speed is set according to a speed preset value, heart rate compensation and flow compensation to reflect the followability of the target speed to the target flow, and the current speed is adjusted based on the target speed; an output adjustment current is calculated based on the difference between the target flow and the current flow, and the difference between the target speed and the current speed, to achieve nested closed-loop control of the speed and flow of the LVAD system, and ultimately the speed and flow will change synchronously with the gear change, thereby meeting the stability and accuracy requirements of cardiac output and speed.

Description

Technical Field

[0001] The present invention relates to medical devices for cardiac surgery and design methods, and in particular to a control device, a ventricular assist system and an adaptive control method. Background Art

[0002] Many end-stage heart diseases develop into heart failure, a major public health issue due to its high prevalence, poor prognosis, and heavy economic burden on patients. Drug therapy for heart failure is primarily suitable for early treatment, while heart transplantation is an effective treatment for severe heart failure. However, a shortage of heart transplant donors limits its widespread clinical application. For these reasons, left ventricular assist devices (LVADs) have gradually become the mainstay of treatment for severe heart failure.

[0003] LVAD is a powered blood pump that can effectively replace more than 80% of the heart's working capacity. It can ensure that the cardiac output and perfusion pressure of heart failure patients remain within a certain physiological range by adjusting the speed.

[0004] In the process of controlling LVAD, in addition to the rotational speed, cardiac output is also a very important reference indicator for users. However, existing control strategies rarely involve the control of cardiac output. Due to the limitation of sensors, the cardiac output between the left ventricle and the aorta cannot be directly measured and can only be reflected by the flow of the catheter pump. Therefore, it is necessary to consider designing a flow feedback control algorithm for the pump. During the control process, the current flow of the pump is also difficult to measure, so it is necessary to provide current and rotational speed for estimation. The estimated flow is then subjected to PI feedback control to meet the accuracy and stability requirements of the flow control, and it is necessary to perform adaptive control of the flow according to different physiological conditions. At the same time, the inner loop rotational speed feedback is considered to achieve nested control of flow and rotational speed. Summary of the Invention

[0005] The present invention discloses a control device, a ventricular assist system and an adaptive control method, which are intended to estimate the current flow of the LVAD according to the heart rate, perform feedback adjustment based on the target flow, and realize that the current flow of the LVAD changes adaptively with the change of the heart rate; further, the target speed is set according to the gear position, heart rate and target flow to reflect the followability of the target speed to the target flow, and the current speed is adjusted based on the target speed; the driving current is calculated according to the difference between the target flow and the current flow, and the difference between the target speed and the current speed, to realize nested closed-loop control of the speed and flow of the LVAD system, and finally the speed and flow will change synchronously with the gear position, thereby meeting the stability and accuracy requirements of cardiac output and speed.

[0006] The present invention adopts the following technical solutions:

[0007] In one aspect, an embodiment of the present invention provides a control device for a ventricular assist system, comprising: a current flow estimation module, a target flow setting module, a target speed setting module, and a current control module;

[0008] The current flow estimation module is used to estimate the current flow based on the current current, the current speed and a preset flow estimation model;

[0009] The target flow setting module is used to calculate the target flow based on the flow preset value and heart rate compensation, and send it to the current control module;

[0010] The target speed setting module is used to calculate the target speed based on the speed preset value, heart rate compensation and flow compensation, and send it to the current control module;

[0011] The current control module is used to provide feedback based on the target flow and target speed, and calculate the flow component and speed component of the current regulation respectively; and calculate the output regulation current based on the flow component and the speed component.

[0012] In a second aspect, an embodiment of the present invention provides a ventricular assist system, comprising a current detection device, a heart rate detection device, a blood pump, and a control device as described above.

[0013] In a third aspect, an embodiment of the present invention provides an adaptive control method for a ventricular assist system, comprising the following steps:

[0014] Estimate the current flow rate based on the current current, the current speed and a preset flow estimation model;

[0015] Calculate target flow based on flow preset value and heart rate compensation;

[0016] The target speed setting module is used to calculate the target speed based on the speed preset value, heart rate compensation and flow compensation;

[0017] Feedback is performed based on the target flow rate and the target speed, and the flow component and the speed component of the current regulation are calculated respectively; the output regulation current is calculated according to the flow component and the speed component.

[0018] In a fourth aspect, an embodiment of the present invention provides an electronic device, including:

[0019] one or more processors;

[0020] a memory for storing one or more programs;

[0021] When the one or more programs are executed by the one or more processors, the one or more processors implement the adaptive control method of the ventricular assist system as described above.

[0022] In a fifth aspect, an embodiment of the present invention provides a readable storage medium, on which an adaptive control program of a ventricular assist system is stored. When the adaptive control program is executed by a processor, the adaptive control method described above can be implemented. One embodiment of the above invention has the following advantages or beneficial effects: the present invention mainly provides a control device, a ventricular assist system, and an adaptive control method. The present invention only needs to obtain heart rate data and current data during the control process of the LVAD to achieve adaptive adjustment of the pump flow and speed based on the gear position and different physiological conditions. The nested closed-loop control of the two can significantly improve the suction problem. Ultimately, the flow and speed of the LVAD will change synchronously with the changes in the gear position and physiological state, meeting the stability and accuracy requirements of both cardiac output and speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0024] Figure 1 A structural block diagram of a control device for a ventricular assist system provided by one embodiment of the present invention;

[0025] Figure 2 A structural block diagram of a left ventricular assist system provided by one embodiment of the present invention;

[0026] Figure 3 A flowchart of an adaptive control method for a ventricular assist system provided by one embodiment of the present invention;

[0027] Figure 4 A block diagram of the coupling system structure of a left ventricular assist system and a blood circulation system provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0028] The following description of exemplary embodiments of the present invention is made in conjunction with the accompanying drawings, in which various details of the embodiments of the present invention are included to facilitate understanding. These details should be considered as merely exemplary. Therefore, it should be appreciated by those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0029] Axial-flow heart pumps are a common type of left ventricular assist device (LVAD). They regulate speed to maintain cardiac output and perfusion pressure within a physiological range for patients with heart failure. In clinical practice, LVADs are often used in parallel to assist the natural heart. If the speed is too low, the heart pump efficiency is insufficient, causing some blood to flow backward from the aorta through the LVAD shunt into the left ventricle. This LVAD regurgitation phenomenon can cause complications such as left ventricular enlargement and blood loss.

[0030] Current LVAD control strategies rarely address cardiac output control. Heart rate fluctuates across different physiological states, and therefore the required cardiac output varies. For example, during muscle exercise, emotional agitation, or pregnancy, cardiac output needs to be increased to maintain the metabolic rate of tissue cells throughout the body. This increase in cardiac output can only be achieved through LVAD gear adjustment, rather than adaptive adjustment. Therefore, this control method cannot fully meet the requirements for flow accuracy. Furthermore, for the same person, heart rate varies during different activities. Failure to adjust gears, or if the parameter settings between adjacent gears are too large or too small to accommodate the changing cardiac output requirements, can lead to problems such as aspiration, potentially causing harm to the patient.

[0031] To solve the above problems, refer to Figure 1 An embodiment of the present invention provides a control device 100 for a ventricular assist system. The control device 100 includes: a current flow estimation module 110, a target flow setting module 120, a target speed setting module 130 and a current control module 140.

[0032] In one embodiment of the present invention, the control device 100 is used in a left ventricular assist system and controls its output current to achieve adaptive adjustment of the rotation speed and flow rate following changes in physiological state; specifically, the left ventricular assist system includes at least a left ventricular assist device LVAD.

[0033] In one embodiment of the present invention, the current flow estimation module 110 is configured to estimate the current flow based on the current current, the current rotation speed, and a preset flow estimation model.

[0034] In one embodiment of the present invention, the current current can be directly detected by the current flow estimation module 110. Based on the current current data, the current speed is calculated using the six-step back electromotive force method. The current current and current speed are input into the fitted flow estimation model to obtain the estimated current flow.

[0035] In one embodiment of the present invention, the state model of the motor and the model of motor torque and current are combined to obtain a model of load torque and current; the model of load torque and current and the model of load torque and flow are combined to obtain a flow estimation model.

[0036] In one embodiment of the present invention, the flow estimation model is obtained based on multivariate regression fitting.

[0037] Specifically, the multivariable regression fitting includes: obtaining simulated current, speed and flow data, and fitting the flow estimation model based on multivariable linear regression; during the fitting process, determining the coefficients of each parameter in the flow estimation model according to the loss function.

[0038] In one embodiment of the present invention, the flow estimation model can be simulated using simulation software such as Matlab, LabVIEW or Ansys. By inputting initial conditions into the simulation software, the simulation results of the model can be output; specifically, the current, speed and flow data input as the initial conditions can be selected from laboratory data.

[0039] In one embodiment of the present invention, the target flow setting module 120 is configured to calculate the target flow based on the preset flow value and heart rate compensation, and send the calculated target flow to the current control module 140 .

[0040] In one embodiment of the present invention, the flow preset value is the flow value corresponding to a certain gear of the left ventricular assist system; the heart rate compensation is obtained by calculating the difference between the current heart rate and the basic heart rate.

[0041] In one embodiment of the present invention, the left ventricular assist system is further provided with at least one sensor capable of collecting current heart rate data, and sending the collected heart rate data to the control device 100 .

[0042] In one embodiment of the present invention, the target flow setting module 120 is also used to receive current heart rate data, and obtain current heart rate change data with reference to the heart rate data in a resting state; based on the flow required by the preset flow value, the flow is compensated according to the current heart rate change data, and the target flow is output.

[0043] In one embodiment of the present invention, the target speed setting module 130 is configured to calculate the target speed based on a preset speed value, heart rate compensation, and flow compensation, and send the calculated target speed to the current control module 140 .

[0044] In one embodiment of the present invention, the speed preset value is also the speed value corresponding to a certain gear of the left ventricular assist system; the heart rate compensation is obtained by calculating the difference between the current heart rate and the basic heart rate.

[0045] In one embodiment of the present invention, the target speed setting module 130 is further used to: obtain target flow change data with reference to the flow rate corresponding to the preset flow value; obtain current heart rate change data with reference to the heart rate data in the resting state; and calculate and output the target speed based on the target flow change data and the current heart rate change data on the basis of the speed required by the preset speed value.

[0046] In one embodiment of the present invention, the current control module 140 is used to provide feedback based on the target flow rate and target speed, and calculate the flow rate component and speed component of the current regulation respectively; and calculate the output regulation current based on the flow rate component and the speed component.

[0047] In one embodiment of the present invention, the current control module 140 is further used to calculate the current-regulated flow component based on the flow PI feedback control model; wherein the input data of the flow PI feedback control model are the current flow and the target flow, and the output data is the current-regulated flow component.

[0048] In one embodiment of the present invention, the current control module 140 is further configured to calculate a speed component for current regulation based on a speed PID feedback control model. The speed PID feedback control model inputs the current current, the current speed, and the target speed, and outputs the current-regulated speed component. Specifically, the current speed is calculated by the current control module 140 based on the current current using a six-step back electromotive force method.

[0049] In one embodiment of the present invention, the current control module 140 is further configured to establish a flow rate PI feedback control model, establish a speed PID feedback control model, and combine the flow rate PI feedback control model with the speed PID feedback control model to calculate the output current. Specifically, the output regulated current is calculated by summing the flow rate component and the speed component of the current regulation.

[0050] refer to Figure 2 An embodiment of the present invention provides a left ventricular assist system, which includes a control device 100, a sensor 200 and a blood pump 300, wherein the control device 100 includes a current flow estimation module 110, a target flow setting module 120, a target speed setting module 130 and a current control module 140; the blood pump 300 includes a motor and an impeller; the sensor 200 includes a current sensor 210 and a heart rate sensor 220.

[0051] In one embodiment of the present invention, except for the heart rate sensor 220, other structures can be regarded as one of the components of the left ventricular assist device LVAD, the outflow duct of the left ventricular assist device is arranged in the aorta, and the inflow duct is arranged in the left ventricle; specifically, the control device 100 stores multiple gears, and its gears can be selected.

[0052] In one embodiment of the present invention, the current sensor 210 , the control device 100 and the blood pump 300 are arranged in sequence. The current sensor 210 can obtain current data and send it to the current flow estimation module 110 of the control device 100 .

[0053] In one embodiment of the present invention, the heart rate sensor 220 can obtain current heart rate data and send it to the target flow rate setting module 120 and the target speed setting module 130 of the control device 100 .

[0054] In one embodiment of the present invention, the control device 100 can estimate the current flow rate of the blood pump 300 based on a flow estimation model and set the target flow rate of the blood pump 300 based on gear position and heart rate compensation. The flow estimation model is derived based on multivariate regression fitting and includes a simultaneous model correlating load torque and current and a model correlating load torque and flow rate. The load torque and current model includes a simultaneous motor state model and a model correlating motor torque and current.

[0055] In one embodiment of the present invention, the control device 100 can set the target speed of the blood pump 300 based on the gear position, heart rate compensation, and flow compensation.

[0056] In one embodiment of the present invention, the control device 100 can provide feedback based on the target flow rate and target speed, and calculate the flow rate component and speed component of the current regulation respectively; and calculate the output regulation current based on the flow rate component and the speed component.

[0057] like Figure 3 The embodiment of the present invention provides an adaptive control method for a ventricular assist system, including steps 410 to 440, as follows:

[0058] Step 410 : Estimate the current flow rate based on the current current, the current speed, and a preset flow rate estimation model.

[0059] In one embodiment of the present invention, before executing step 410, the process further includes step 400: establishing a flow estimation model based on the data and the model, and performing multivariate regression fitting on the parameters of the model.

[0060] In one embodiment of the present invention, a left ventricular assist device (LVAD) is disposed between the left ventricle and the aorta, and its structure mainly includes a control device 100, a motor, an impeller, a current sensor 210, etc., wherein the motor and the impeller are assembled into a blood pump structure; the LVAD can pump blood in the left ventricle into the aorta to provide the blood volume required for circulation.

[0061] In one embodiment of the present invention, the LVAD can adjust the gear, and different gears correspond to different speed and flow preset values. When designing the gear, the speed and flow corresponding to different gears are set according to the output capacity of the pump.

[0062] In one embodiment of the present invention, LVAD gear 1 corresponds to a flow rate of 1-1.5 L / min and a rotational speed of 10,000 rpm; gear 2 corresponds to a flow rate of 2-2.5 L / min and a rotational speed of 20,000 rpm; and gear 3 corresponds to a flow rate of 3-3.5 L / min and a rotational speed of 30,000 rpm. Those skilled in the art will appreciate that, because users have varying physiological conditions and flow and rotational speed are inherently coupled, gear design should be tailored to the user's actual physiological conditions. Furthermore, because users have varying heart rates under different physiological / pathological conditions or environments, and an increase in heart rate directly increases circulating blood volume, the flow rate and rotational speed corresponding to the gears are progressively increased to match the user's physiological conditions.

[0063] In one embodiment of the present invention, the method further includes step 401: establishing a state equation of the motor and an equation relating motor torque and current respectively, and combining the two equations to obtain an equation relating load torque and current.

[0064] For the motor, its state equation is as follows:

[0065]

[0066] Where J is the motor’s moment of inertia, T e is the motor torque, T p is the load torque, B is the damping coefficient, and w is the motor angular velocity. To determine the angular velocity w, we can measure the motor's back EMF, detect magnetic field commutation, and further determine the current speed n. Using the speed-to-angular velocity conversion formula w = 2πn, we can calculate the motor's angular velocity.

[0067] Furthermore, the equation relating motor torque to current is:

[0068]

[0069] Among them, K b is the motor back electromotive force constant, and I is the current.

[0070] Combining the above equations (1) and (2), we can get the equation related to the motor's load torque and current:

[0071]

[0072] In one embodiment of the present invention, the method further includes step 402: establishing an equation relating load torque to pump flow, and simultaneously establishing equations relating load torque to current and pump flow to obtain a flow estimation model.

[0073] Since the load torque is related to the pump body, the equation relating the load torque to the pump flow is:

[0074] T p =a1w 2 +a2F 2 (4)

[0075] Where F is the flow rate of the pump, and a1 and a2 are constant coefficients.

[0076] By combining the above equations (3) and (4), a flow estimation model can be obtained. However, it is obvious that the parameter coefficients a1 and a2 in the model cannot be determined after combining (3) and (4). Therefore, step 403 is also included: collecting data on the current, speed and flow of the motor, and fitting the model based on multivariable linear regression; during the fitting process, the parameter coefficients in the model are determined according to the loss function.

[0077] Since there is no corresponding flow sensor in the human body to detect the actual flow data, when fitting the model, the flow data in the model is detected by the flow collector in the experimental stage. Correspondingly, the current and speed are also detected in the experimental stage, and then the load torque T is solved by the speed and current. p .

[0078] In one embodiment of the present invention, the variables in the above formula (4) are transformed, and y=T p , x1=w 2 , x2=F 2 . The purpose is to determine a1 and a2 of the following formula:

[0079] y=a1x1+a2x2 (5)

[0080] Take i=1,2,…,n as sampling points, perform gradient descent fitting on Equation (5), and select the loss function as:

[0081]

[0082] Among them, the independent variables of the loss function are a1 and a2.

[0083] From the above formula (6), we can get:

[0084]

[0085] Where j=1,2 represents the subscript of the independent variable.

[0086] Based on the above formula (7), the step size of the gradient descent is taken as α, then a1 and a2 can be iteratively fitted using the following formula:

[0087]

[0088] After the parameter coefficients a1 and a2 are fitted, the flow rate can be directly estimated through the flow estimation model based on the deformation of the above formula (4), that is:

[0089]

[0090] Step 411: Acquire current data and estimate the current flow rate based on the fitted model.

[0091] In one embodiment of the present invention, the current (A) data in the LVAD at this time is detected by the current sensor 210, and the current speed is calculated according to the six-step back electromotive force method, and the current current and the current speed are input into the fitted flow estimation model to obtain the current flow.

[0092] In one embodiment of the present invention, the value of the current flow rate is calculated according to the above formula (10).

[0093] Those skilled in the art should understand that, since the calculated current flow value is obtained by a fitted model, it is essentially an estimate of the current flow, rather than the actual current flow value.

[0094] Step 420: Calculate the target flow rate based on the preset flow rate value and heart rate compensation.

[0095] Because existing LVADs do not include a heart rate detection module, heart rate data is not directly measured by the LVAD. Instead, it is detected by another heart rate sensor 220 (such as a wearable heart rate monitor), which then transmits the detected data to the LVAD control device 100. Those skilled in the art will understand that a user's different physiological conditions, age, pathological conditions, medications, emotional changes, etc. can all cause changes in heart rate. Therefore, the heart rate detection device should transmit the user's heart rate to the LVAD in real time for feedback and adjustment.

[0096] In one embodiment of the present invention, the preset flow rate value can be set or adjusted through different gears of the LVAD.

[0097] To ensure that the flow rate changes adaptively with the heart rate, the heart rate variation difference should also be calculated. Therefore, in one embodiment of the present invention, step 421 is further included: using the resting heart rate data as a reference to obtain the current heart rate variation data; based on the required flow rate for the gear, the flow rate is compensated according to the current heart rate variation data to output the target flow rate.

[0098] Those skilled in the art should understand that the heart rate of a normal adult at rest is between 60 and 100 beats per minute, and each person's basal heart rate is different. Therefore, the user's heart rate at rest should be detected first, and the heart rate data should be used as the reference heart rate. Then the current heart rate should be detected, and the difference between the two is the change data of the current heart rate.

[0099] As described in step 410 above, the human body requires different flow rates in different physiological states. For example, when a user is active or excited, their heart rate increases due to neural stimulation, requiring a higher cardiac output. However, after exercise or in a resting state, their heart rate decreases, requiring a lower cardiac output. If the same flow rate as during exercise is still delivered, it may cause pumping and other harmful effects. Therefore, the target flow rate needs to be compensated based on the gear level, increasing the flow rate when the heart rate is high and decreasing it when the heart rate is low. This achieves positive feedback regulation and adaptive adjustment based on different physiological conditions.

[0100] The target flow rate compensates the flow rate based on the flow rate set by the gear. The target flow rate is calculated as follows:

[0101] F set =u1=F d +K1(bt measure -bt rest ) (11)

[0102] Among them, K1 is the coefficient, F set is the target flow, F d Set the flow rate required for the gear, bt measure is the current measured heart rate, bt rest is the heart rate at rest. Taking the resting heart rate as the reference standard, the target flow rate is controlled to change adaptively with the heart rate. Figure 4 , the value calculated by the above formula (11) outputs the target flow through u1.

[0103] Specifically, different LVADs have different output capacities, so the actual flow rate should be designed based on the LVAD's specific needs. For example, an LVAD with a flow rate of 0-5 L / min can be divided into multiple levels based on the user's actual needs, such as Level 1 (1-1.5 L / min), Level 2 (2-2.5 L / min), and Level 3 (3-3.5 L / min). During use, the doctor will determine the flow rate required by the user and select the level that corresponds to the patient's needs.

[0104] Specifically, the coefficient K1 in the above formula (11) is obtained from experiments. According to the changes in heart rate and required flow rate, a model is established, and dbt=bt measure -bt rest, dF=F set -F d , the relationship between dF and dbt is obtained through experimental data, and then data fitting is performed to further obtain the range of K1 values.

[0105] In one embodiment of the present invention, step 422 is further included: calculating the flow component for current regulation based on the flow PI feedback control model. In one embodiment of the present invention, since the target flow and the current flow obtained from the model differ, there will be a difference between the two. In this case, feedback adjustment of the current flow is necessary to stabilize it near the target flow and enable the current flow to adapt to changes in heart rate. Because flow is continuous, PI feedback control is performed on the current flow to reduce the computational burden of the control process.

[0106] Specifically, the target flow rate is subtracted from the current flow rate calculated by the above formula (10) to obtain the current flow rate difference, which is expressed as F e , so the flow PI feedback control model is:

[0107]

[0108] Among them, K Fp and K Fi is the flow control parameter, which is obtained according to actual debugging, for example, increasing K Fp It can improve the dynamic response speed and increase K Fi Improve the steady-state accuracy. The specific debugging process will not be described here.

[0109] Step 430: Calculate the target speed based on the preset speed value, heart rate compensation, and flow compensation.

[0110] In one embodiment of the present invention, the preset speed value can be set or adjusted through different gears of the LVAD.

[0111] In one embodiment of the present invention, step 431 is also included: using the flow corresponding to the gear as a reference, obtaining the change data of the target flow; using the heart rate data in the resting state as a reference, obtaining the change data of the current heart rate; based on the speed required by the gear, the speed is compensated according to the change data of the target flow and the change data of the current heart rate to output the target speed.

[0112] In one embodiment of the present invention, the target speed is not only determined by the gear position, but also requires a certain speed compensation according to the change of the current heart rate and the change of the target flow rate.

[0113] Specifically, since the flow rate and speed are coupled, when the target flow rate changes, the target speed should also be adjusted accordingly; and when the current heart rate changes, the required cardiac output will change, which will also directly affect the target speed. Therefore, the change data of the target flow rate and the change data of the current heart rate should be taken into account, and the two together compensate for the target speed to output the target speed.

[0114] In one embodiment of the present invention, the formula for the target speed is:

[0115] n set =u2=n d +K2(bt measure -bt rest )+K3(F set -F d ) (13)

[0116] Among them, K2 and K3 are coefficients, n d K2 and K3 are obtained according to actual debugging. The specific debugging method refers to the debugging process of K1 in step 421 above, which will not be repeated here. Figure 4 The value calculated by the above formula (13) is output as the target speed through u2.

[0117] In equation (13), to achieve adaptive speed regulation, compensation terms based on changes in heart rate and target flow rate are added. This allows the target speed to be adjusted based on the user's physiological conditions, consistent with target flow rate control. When a user uses an LVAD, their heart rate and cardiac output requirements increase as their activity level increases. Therefore, compensation for the target flow rate is combined with compensation for the target speed.

[0118] In one embodiment of the present invention, step 432 is further included: calculating the speed component of the current regulation based on the speed PID feedback control model. In one embodiment of the present invention, since the target speed and the current speed calculated using the six-step back EMF method (in this case, the current speed is an estimate, not the actual value) differ, there is a difference between the two. In this case, feedback adjustment of the current speed is necessary to stabilize it near the target speed and enable it to adapt to changes in heart rate and target flow.

[0119] Specifically, the target speed is subtracted from the current speed obtained by back electromotive force to calculate the current speed difference, which is expressed as n e , based on the current speed difference n e For the current speed, PID feedback control is performed. The speed PID feedback control model is:

[0120]

[0121] Among them, K np , K ni , K nd The speed control parameter is obtained according to actual debugging. For specific debugging methods, refer to the above step 422 for K Fp , K Fi The debugging process will not be described here.

[0122] Step 440: Based on the target flow rate and the target speed, feedback is performed to calculate the flow rate component and the speed component of the current regulation respectively; and the output regulation current is calculated according to the flow rate component and the speed component.

[0123] In one embodiment of the present invention, the output regulation current is calculated by combining equations (12) and (14) to perform feedback control. Therefore, the calculation formula of the driving current is:

[0124] I=f n (n e )+f F (F e ) (15)

[0125] like Figure 4 The value calculated by the above formula (15) outputs the driving current through u3.

[0126] Through the feedback control of equation (15), nested closed-loop control of the system speed and flow is achieved. Ultimately, the speed and flow will change synchronously with the gear position, meeting the stability and accuracy requirements of cardiac output and speed.

[0127] In the above steps, only the heart rate data and the current current data need to be obtained to achieve adaptive adjustment of the flow and speed in the LVAD. The two will then feedback and adjust the current current data, so that the cardiac output can match the user's physiological state while ensuring the stability of the adjustment.

[0128] In one embodiment of the present invention, an electronic device is also provided, which includes at least one processor and a memory, and the memory is used to store one or more programs. When the one or more programs are executed by the processor, the processor can implement the adaptive control method of the ventricular assist system as described above.

[0129] In one embodiment of the present invention, a readable storage medium is further provided, on which an adaptive control program of a ventricular assist system is stored. When the adaptive control program is executed by a processor, the functions that can be achieved by steps 410 to 440 can be achieved.

[0130] It should be noted that the left ventricular assist system and the adaptive control method embodiment of the ventricular assist system provided in the above embodiments belong to the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0131] Those skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware, or by a program to instruct the relevant hardware, and the program may be stored in a computer-readable storage medium, which may be a read-only memory, a disk, or an optical disk, etc.

[0132] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are protected by the present invention.

Claims

1. A control device for a ventricular assist system, characterized in that: include: Current flow estimation module, target flow setting module, target speed setting module and current control module; The current flow estimation module is used to estimate the current flow based on the current current, the current speed and a preset flow estimation model; The target flow setting module is used to calculate the target flow based on the flow preset value and heart rate compensation, and send it to the current control module; The target speed setting module is used to calculate the target speed based on the preset speed value, heart rate compensation and flow compensation, and send it to the current control module; The current control module is used to provide feedback based on the target flow rate and the target speed, and to determine the flow component of the current regulation according to the difference between the current flow rate and the target flow rate, and to determine the speed component of the current regulation according to the difference between the current speed and the target speed; The output regulating current is calculated based on the flow component and the speed component.

2. The control device according to claim 1, characterized in that The current flow estimation module is further configured to: Simultaneously establishing a model relating load torque to current and a model relating load torque to flow rate to obtain the flow rate estimation model; The load torque and current correlation model includes a joint motor state model and a motor torque and current correlation model.

3. The control device according to claim 2, characterized in that The flow estimation model is obtained based on multivariate regression fitting; The multivariate regression fitting includes: Acquire simulated current, speed and flow data, and fit the flow estimation model based on multivariate linear regression; During the fitting process, the coefficients of each parameter in the flow estimation model are determined according to the loss function.

4. The control device according to claim 3, characterized in that The current flow estimation module is further configured to: The current current data is received, the current rotation speed is calculated based on the current current and the back electromotive force, and the current current and the current rotation speed are input into the fitted flow estimation model to obtain an estimated current flow.

5. The control device according to claim 1, characterized in that The target flow setting module is also used for: Receive current heart rate data, and use the heart rate data in a resting state as a reference to obtain current heart rate change data; On the basis of the flow required by the preset flow value, flow compensation is performed according to the current heart rate change data, and the target flow is output.

6. The control device according to claim 1, characterized in that The target speed setting module is further configured to: Taking the flow rate corresponding to the preset flow rate as a reference, the change data of the target flow rate is obtained; Using the heart rate data in the resting state as a reference, obtain the current heart rate change data; On the basis of the speed required by the preset speed value, the target speed is calculated and output according to the change data of the target flow rate and the change data of the current heart rate.

7. The control device according to claim 1, characterized in that The current control module is further configured to: Calculate the flow component of current regulation based on the flow PI feedback control model; The input data of the flow PI feedback control model are the current flow and the target flow, and the output data is the flow component regulated by the current.

8. The control device according to claim 1, characterized in that The current control module is further configured to: Calculate the speed component of current regulation based on the speed PID feedback control model; The input data of the speed PID feedback control model are the current current, the current speed and the target speed, and the output data is the speed component regulated by the current.

9. The control device according to claim 8, characterized in that The current control module is further configured to: Obtain the current current data and calculate the current speed based on the six-step back electromotive force method.

10. The control device according to claim 1, characterized in that The current control module is further configured to: Establish flow PI feedback control model; Establish a speed PID feedback control model; The flow PI feedback control model and the speed PID feedback control model are combined to calculate the output current.

11. A ventricular assist system, characterized in that: The device comprises a current detection device, a heart rate detection device, a blood pump, and a control device as claimed in any one of claims 1 to 10.

12. An electronic device, characterized in that: include: one or more processors; a memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement adaptive control of the ventricular assist system as claimed in claim 11.

13. A readable storage medium, characterized in that: The readable storage medium stores an adaptive control program for the ventricular assist system. When the adaptive control program is executed by the processor, it can implement adaptive control of the ventricular assist system as claimed in claim 11.

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