Gas-tight pressure regulator for a gas-tight pressure regulator for a gas-tight pressure regulator for a gas-tight pressure regulator for a gas-tight pressure regulator for a gas-tight pressure regulator for a gas-tight pressure

Abstract

The application discloses a gas-tight pressure stabilizing type pneumoperitoneum machine and process suitable for forced negative pressure working conditions, and the process comprises the following steps: (1) obtaining a control variable by using a PID algorithm; and (2) pressure regulation. In one aspect, the application is based on the PID algorithm to dynamically adjust the comprehensive output of the control variable, solves the problem of gas-tight space failure in the working condition that the forced generated negative pressure causes the peritoneal cavity pressure to rapidly decrease, makes the gas-tight pressure meet the use requirement, and meanwhile, the negative pressure device can also complete the negative pressure processing target under the working condition that the required time and the changed pressure difference, in another aspect, in the process of forced generated negative pressure and negative pressure closing, the formed gas-tight pressure rises stably, and the problems of insufficient gas supply or excessive gas supply do not occur, so that the gas-tight pressure can work on the basis of normal establishment of artificial gas-tight pressure, and the human body is not damaged, and complications such as high gas-tight pressure syndrome are prevented.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of medical devices, and particularly relates to a gas-tight pressure stable regulation type pneumoperitoneum machine suitable for forced negative pressure working condition, and also relates to a gas-tight pressure stable regulation process suitable for forced negative pressure working condition. BACKGROUND

[0002] The pneumoperitoneum machine is a special device for establishing and maintaining gas-tight in laparoscopic surgery, and its main function is to establish artificial gas-tight, that is, to separate the abdominal wall and organs by mechanical pressurization and inflation of the pneumoperitoneum machine, so as to provide sufficient operation space for the surgery and avoid damage to the organs when the puncture sleeve is inserted into the abdominal cavity. Specifically, the working principle is that the CO2 gas source is subjected to multi-stage pressure reduction and flow proportional valve regulation, then enters the main machine, passes through the filter and the on-off valve, and then passes through the sensor, and finally enters the abdominal cavity, and the gas entering the abdominal cavity needs to be maintained within a certain reasonable range, because if the gas supply of the pneumoperitoneum machine is insufficient, the artificial gas-tight cannot be normally established, thereby seriously affecting the smooth development of the clinical surgery; if the gas supply of the pneumoperitoneum machine is excessive or excessive, the human body is easily damaged.

[0003] However, in the use of the pneumoperitoneum machine, a negative pressure device is generally matched, the negative pressure device is in communication with the abdominal cavity, and the function of the negative pressure device is not limited to "gas extraction", but cooperates with the positive pressure inflation system to realize: a) dynamic pressure control, avoid high pressure damage, adapt to the operation demand; b) rapid environmental cleaning: maintain clear surgical field, improve operation efficiency; c) emergency safety guarantee, provide rapid intervention means for emergency situations. Therefore, this two-way control capability makes the pneumoperitoneum machine become a reliable life support device in laparoscopic surgery, but in the use process of the negative pressure device, the following technical defects exist:

[0004] 1) Once the negative pressure device is opened, a forced negative pressure (forced negative pressure refers to that in a specific area, a low atmospheric pressure state lower than the surrounding environment is artificially created by mechanical equipment or other means, and this state is usually set to promote air flow, extract pollutants or control gas flow) is generated, and the gas follows the flow principle of pressure difference driving, and flows from the area with higher pressure to the negative pressure area. Specific working conditions, combined with Figure 1 the P-T curve shown in FIG. 1, from the curve, it can be seen that when the negative pressure is less than or equal to the injection pressure, the front P-T curve is in a relatively stable state, and once the negative pressure is greater than the injection pressure, the rear P-T curve is in a obviously steep decline state, therefore, the pressure change presented will cause the abdominal cavity pressure to drop rapidly and result in the failure of the gas-tight space, thereby failing to meet the use needs;

[0005] 2) in the condition of generating forced negative pressure, if the gas injection amount is directly adjusted by the flow proportional valve based on the change of pressure value only, the abdominal cavity pressure will be over-adjusted, which will cause human body injury, so there is a great safety hazard, and such gas injection mode will also cause the negative pressure device to fail to achieve the expected target. SUMMARY

[0006] The technical problem to be solved by the present application is to overcome the shortcomings of the prior art and provide an improved gas-tube pressure stable adjustment process suitable for forced negative pressure conditions.

[0007] Meanwhile, the present application also relates to a gas-tube pressure stable adjustment type gas-tube machine suitable for forced negative pressure conditions.

[0008] To solve the above technical problems, the technical solutions adopted by the present application are as follows:

[0009] A gas-tube pressure stable adjustment process suitable for forced negative pressure conditions, which adopts a PID algorithm control mode for pressure adjustment, wherein when the preset pressure p_exp and the current pressure value p_cur are monitored, and the preset pressure p_exp > the current pressure value p_cur, the adjustment is started, and the process includes the following steps:

[0010] (1) PID algorithm obtains control amount

[0011] Firstly, the deviation value ERR_P is calculated, wherein ERR_P = p_exp - p_cur, and the obtained proportional control amount is ERR_P x Kp, and Kp is the proportional coefficient; secondly, the integral operation is performed on the deviation value ERR_P to obtain ERR_I, and the integral control amount is ERR_I x Ki, and Ki is the integral coefficient; thirdly, the differential operation is performed on the deviation value ERR_P to obtain ERR_D, and the differential control amount is ERR_D x Kd, and Kd is the differential coefficient; finally, the proportional, integral and differential three control amounts are fitted to form the control amount comprehensive output;

[0012] (2) pressure adjustment

[0013] The parameter value size of Kp, Ki and Kd in step (1) is dynamically adjusted based on the change rate of the gas-tube pressure drop, so as to output the control amount in real time and dynamically, so that the gas-tube pressure is reduced based on the cooperation of the gas injection amount and the gas injection speed in the forced negative pressure condition, and the change rate of the gas-tube pressure drop is reduced, and in the required time, the pressure difference size change is completed based on the forced negative pressure to achieve the negative pressure processing target, and after the limit safety gas-tube pressure is reached, the negative pressure is closed, and based on the parameter value reduction of Kd and Ki, the gas-tube pressure is continuously increased in the control amount comprehensive output until p_exp = p_cur.

[0014] Preferably, the proportional control amount is directly proportional to the ERR_P value. In short, the proportional control amount functions to quickly adjust the gas flow according to the size of the deviation, and the greater the deviation, the greater the adjustment. For example, if the insufflation pressure is much lower than the preset value, the proportional control amount will cause the flow regulating valve to quickly increase the opening degree, thereby increasing the gas flow.

[0015] According to a specific implementation and preferred aspect of the present application, the integral operation formula is: where Ki = Ti / Kp, Ti is the integral time constant; e(τ) is the error signal, and is the deviation between the set value and the actual output value; τ is the integral variable, representing the cumulative process of time from the initial time 0 to the current time t.

[0016] Preferably, e(τ) = r(τ) - y(τ), where r(τ) is the set value, and y(τ) is the actual output value.

[0017] In some specific implementations, ERR_I = ERR_I + ERR_P, where the initial value of ERR_I is 0. The integral control amount functions to eliminate the steady-state error of the system. When there is a persistent deviation in the insufflation pressure, the integral element will gradually accumulate, causing the gas flow to be continuously adjusted until the deviation is eliminated.

[0018] According to another specific implementation and preferred aspect of the present application, the differential operation formula is: where Kd = Kp x Td, is the rate of change of the error signal with respect to time, reflecting the trend of the error; Td is the differential time constant

[0019] In some specific implementations, the differential control amount ERR_D = ERR_D - ERR_P, where the initial value of ERR_D is 0. The differential control amount functions to adjust the gas flow in advance according to the trend of the insufflation pressure. When a rapid decrease in the insufflation pressure is detected, the differential control amount will cause the flow regulating valve to increase the opening degree more quickly, in order to cope with the possible greater pressure loss.

[0020] According to another specific implementation and preferred aspect of the present application, the control amount comprehensive output = Kp x (ERR_P) + Ki x (ERR_I) + Kd x (ERR_D). In short, the comprehensive control output: the sum of the proportional, integral, and differential control amounts is obtained, which is the final control output value used to control the opening degree of the flow regulating valve, thereby adjusting the gas flow. If the comprehensive control output value increases, the opening degree of the flow regulating valve increases, the gas flow increases, and the insufflation pressure is thereby increased.

[0021] According to another specific implementation and preferred aspect of the present application, the rate of change of the pneumoperitoneum pressure drop dynamically comprises a pressure rapid condition and a pressure slow drop condition. In the pressure rapid condition, the adjustment of the control quantity comprehensive output is based on increasing the Kp and Kd values and simultaneously decreasing the Ki value. In short, the Kp value is increased to rapidly increase the gas flow to inhibit the rapid drop of the pressure, and the integral coefficient Ki is decreased to avoid excessive overshoot of the integral link during the rapid change. In the pressure slow drop condition, the adjustment of the control quantity comprehensive output is based on increasing the Ki value while the Kp and Kd values remain unchanged. That is, when the pneumoperitoneum pressure drop is relatively slow, the integral coefficient Ki can be appropriately increased to make the integral link play a more active role in the long-term pressure adjustment, while the proportional coefficient Kp and the differential coefficient Kd are maintained at a moderate value to stably increase the gas flow to compensate for the pressure loss.

[0022] In some specific implementations, a safety reference value of the pneumoperitoneum pressure is set, and in the forced negative pressure condition of step (2), the limit safety pneumoperitoneum pressure is greater than or equal to the safety reference value of the pneumoperitoneum pressure. In short, the pressure is controlled based on the PID algorithm to solve the situation that the forced negative pressure causes the abdominal pressure to drop extremely rapidly, and still maintains a period of time for normal surgery to ensure normal surgery.

[0023] According to another specific implementation and preferred aspect of the present application, in the forced negative pressure condition of step (2), the pressure change of the pneumoperitoneum pressure is divided into a first drop segment, a rising segment, a second drop segment, and a third drop segment, wherein the pressure change rates of the three drop segments are V1, V2, and V3 respectively, and V1

[0024] Preferably, the time used in the rising segment is t4, wherein t4

[0025] In some specific implementations, when the forced negative pressure is not performed, the pressure formed by the pneumoperitoneum is an original pressure value, and the maximum value of the pneumoperitoneum pressure in the rising segment is less than or equal to the original pressure value. This avoids the human body damage caused by the instantaneous excessive injection of the gas flow.

[0026] In addition, at the negative pressure closing time of step (2), the pneumoperitoneum pressure constitutes the initial rising stage and the constant rising stage, in which the control amount comprehensive output is changed based on the parameter values of Kd and Ki. After the negative pressure closing, the pneumoperitoneum pressure recovers, and under the action of the insufflation pressure, the pneumoperitoneum pressure starts to rise steadily after the forced negative pressure Pq is closed. The control system continues to monitor the pneumoperitoneum pressure, and according to the pressure rising condition, gradually adjusts the gas flow. When the pneumoperitoneum pressure approaches the preset pressure value, the flow is finely adjusted through the PID algorithm, so that the pneumoperitoneum pressure accurately reaches the preset pressure value, and returns to the normal surgical pneumoperitoneum state. In this process, the PID parameters may need to be adjusted again, for example, the proportional coefficient Kp and the integral coefficient Ki are appropriately reduced, so as to avoid the over-regulation of the pneumoperitoneum pressure. The whole process ensures that the change of the pneumoperitoneum pressure is smooth, and does not have adverse effects on the surgical operation and the physiological state of the patient.

[0027] Another technical solution of the present application is a pneumoperitoneum machine suitable for forced negative pressure working condition and capable of stabilizing the pneumoperitoneum pressure, which comprises a pneumoperitoneum main machine, a gas supply device and a negative pressure device, wherein the negative pressure device and the pneumoperitoneum main machine are in communication with a pneumoperitoneum cavity, the gas supply device is in communication with the pneumoperitoneum main machine, and the pneumoperitoneum main machine adjusts the injection or discharge of the gas based on the pressure change in the pneumoperitoneum cavity, in particular, the adjustment process is the above-mentioned process suitable for forced negative pressure working condition and capable of stabilizing the pneumoperitoneum pressure.

[0028] Due to the implementation of the above technical solutions, the present application has the following advantages compared with the prior art:

[0029] When the existing pneumoperitoneum machine is used with the negative pressure device, the forced negative pressure (the forced negative pressure refers to the state that a lower atmospheric pressure than the surrounding environment is artificially created in a specific area through mechanical equipment or other means, which is usually set to promote air flow, extract pollutants or control gas flow direction), the gas will flow from the area with higher pressure to the negative pressure area according to the flow principle driven by the pressure difference. In specific working conditions, combined with Figure 1As shown, the P-T curve when the negative pressure is less than or equal to the gas injection pressure to the P-T curve when the negative pressure is greater than the gas injection pressure, from which it can be seen that when the negative pressure is less than or equal to the gas injection pressure, the front P-T curve is in a relatively stable state, and once the negative pressure is greater than the gas injection pressure, the rear P-T curve is in a state of obvious steep decline, therefore, the pressure change will cause the abdominal cavity pressure to drop rapidly and cause the pneumoperitoneum space to fail, thereby failing to meet the use needs; in the working condition of generating forced negative pressure, if only based on the size change of the pressure, the gas injection amount is directly adjusted through the flow proportional valve, then the abdominal cavity pressure will be over-adjusted to cause the human body injury rate, therefore, there are great safety hazards, and such a gas injection mode will also cause the negative pressure device to fail to achieve the expected target and the like, and the present application ingeniously solves various existing deficiencies by overall design of the pneumoperitoneum pressure stable adjustment process suitable for the forced negative pressure working condition, after adopting the pneumoperitoneum pressure stable adjustment process, firstly, the control amount is obtained based on the PID algorithm, wherein the proportional, integral and differential three control amounts are fitted to form a control amount comprehensive output; secondly, the parameter value size of Kp, Ki and Kd in step (1) is dynamically adjusted based on the change rate of the pneumoperitoneum pressure drop, so as to output the control amount in a real-time dynamic adjustment mode, so that the pneumoperitoneum pressure reduces the change rate of the pneumoperitoneum pressure drop based on the cooperation of the gas injection amount and the gas injection speed in the forced negative pressure working condition, at the same time, the pressure difference size change is completed based on the forced negative pressure to form the negative pressure processing target in the required time, and the negative pressure is closed after the drop to the limit safety pneumoperitoneum pressure, and the parameter value of Kd and Ki is reduced, and the pneumoperitoneum pressure is continuously increased in the control amount comprehensive output until p_exp=p_cur, therefore, on the one hand, the control amount comprehensive output is dynamically adjusted based on the PID algorithm to solve the problem of pneumoperitoneum space failure in the working condition of forced generated negative pressure causing the abdominal cavity pressure to drop rapidly, so that the pneumoperitoneum pressure meets the use needs, and the negative pressure device can also complete the negative pressure processing target under the required time and change pressure difference working condition; on the other hand, the pneumoperitoneum pressure rises stably in the process of forced generated negative pressure and negative pressure closing, and there is no gas supply shortage or excessive gas supply, so that it works on the basis of normal establishment of artificial pneumoperitoneum, and will not cause damage to the human body, and prevent complications such as high pneumoperitoneum pressure syndrome. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a P-T curve schematic diagram of the prior art when the negative pressure is less than or equal to the gas injection pressure to the negative pressure is greater than the gas injection pressure;

[0031] Figure 2 It is a P-T curve schematic diagram of the present application when the negative pressure is greater than the gas injection pressure to the negative pressure is closed;

[0032] Figure 3 It is a structure schematic diagram of the pneumoperitoneum machine of the present application;

[0033] Wherein: 1, the gas abdominal main machine; 2, gas supply device; 3, negative pressure device; 4, gas abdominal cavity. DETAILED DESCRIPTION

[0034] In order to make the above objectives, features and advantages of the present application more apparent, the present application will be described in detail below with the accompanying drawings and specific embodiments. In the following description, a large number of specific details are set forth in order to facilitate a full understanding of the present application. However, the present application can be implemented in many different ways other than those described herein, and those skilled in the art can make similar improvements without departing from the scope of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0035] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0036] In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0037] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0038] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature "over", "above" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher than the second feature in horizontal height. The first feature "under", "below" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower than the second feature in horizontal height.

[0039] It should be noted that when an element is referred to as "fixed to" or "provided on" another element, it can be directly on the other element or there can be an intermediate element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there can be an intermediate element. The terms "vertical", "horizontal", "up", "down", "left", "right" and the like used herein are for illustrative purposes only and are not the only implementation.

[0040] As shown in Figure 2 and Figure 3 The embodiment relates to a gas pressure stable adjustment type pneumoperitoneum machine suitable for forced negative pressure working conditions, which comprises a pneumoperitoneum main machine 1, a gas supply device 2 and a negative pressure device 3, wherein the negative pressure device 3 and the pneumoperitoneum main machine 1 are in communication with a pneumoperitoneum cavity 4, the gas supply device 2 is in communication with the pneumoperitoneum main machine 1, and the pneumoperitoneum main machine 1 adjusts the injection or discharge of gas based on the pressure change in the pneumoperitoneum cavity 4.

[0041] Specifically, the CO2 gas source→0th stage pressure reducing valve→1st stage→2nd stage→flow proportional valve→inlet filter→inlet on-off valve→pneumoperitoneum pipeline→pressure sensor→flow sensor→abdominal cavity.

[0042] In some specific embodiments, the pneumoperitoneum pressure stable adjustment process of the above-mentioned pneumoperitoneum machine adopts a PID algorithm control mode for pressure adjustment, wherein when the preset pressure p_exp and the current pressure p_cur are monitored, and the preset pressure p_exp > the current pressure p_cur, the adjustment is started, and the process comprises the following steps:

[0043] (1) PID algorithm obtains control quantity

[0044] First, a deviation value ERR_P is calculated, where ERR_P = p_exp - p_cur, and the proportional control amount is ERR_P x Kp, where Kp is a proportional coefficient. Second, the deviation value ERR_P is integrated to obtain ERR_I, and the integral control amount is ERR_I x Ki, where Ki is an integral coefficient. Third, the deviation value ERR_P is differentiated to obtain ERR_D, and the differential control amount is ERR_D x Kd, where Kd is a differential coefficient. Finally, the proportional, integral, and differential control amounts are combined to form a comprehensive control amount output.

[0045] (2) Pressure regulation

[0046] The parameter values of Kp, Ki, and Kd in step (1) are dynamically adjusted based on the rate of change of the pneumoperitoneum pressure drop, so that the output control amount is dynamically adjusted in real time, so that the pneumoperitoneum pressure drop rate is reduced based on the cooperation of the gas injection amount and the gas injection speed in the forced negative pressure condition, and the pressure difference size change based on the forced negative pressure is completed within the required time to achieve the negative pressure processing target, and the negative pressure is closed after the pressure drops to the limit safety pneumoperitoneum pressure, and the parameter values of Kd and Ki are reduced, and the pneumoperitoneum pressure is continuously increased in the comprehensive control amount output until p_exp = p_cur.

[0047] In step (1), the proportional control amount is directly proportional to the ERR_P value. In short, the proportional control amount quickly adjusts the gas flow according to the size of the deviation, and the larger the deviation, the greater the adjustment. For example, if the pneumoperitoneum pressure is much lower than the preset value, the proportional control amount will cause the flow regulating valve to quickly increase the opening degree and increase the gas flow. The integral operation formula is: where Ki = Ti / Kp, Ti is the integral time constant, e(τ) is the error signal, and is the deviation between the set value and the actual output value, and τ is the integral variable, representing the cumulative process of time from the initial time 0 to the current time t. e(τ) = r(τ) - y(τ), where r(τ) is the set value and y(τ) is the actual output value. In some specific embodiments, ERR_I = ERR_I + ERR_P, where the initial value of ERR_I is 0. The role of the integral control amount is to eliminate the steady-state error of the system. When there is a persistent deviation in the pneumoperitoneum pressure, the integral element will gradually accumulate, causing the gas flow to be continuously adjusted until the deviation is eliminated. The differential operation formula is: where Kd = Kp x Td, is the rate of change of the error signal over time, reflecting the trend of the error; Td is the differential time constant. In some embodiments, the differential control ERR D = ERR D - ERR P, where the initial value of ERR D is 0. The role of the differential control is to adjust the gas flow in advance according to the trend of the change in the pneumoperitoneum pressure. When a faster drop in the pneumoperitoneum pressure is detected, the differential control will cause the flow regulating valve to increase the opening more quickly to cope with the possible greater pressure loss. The integrated output of the control = Kp x (ERR P) + Ki x (ERR I) + Kd x (ERR D). In short, the integrated output of the control: add the three controls of proportion, integration, and differentiation to obtain the final control output value, which is used to control the opening of the flow regulating valve, thereby adjusting the gas flow. If the integrated output value of the control increases, the opening of the flow regulating valve increases, the gas flow increases, and in turn the insufflation pressure increases. At the same time, there is a correlation between the parameter values of Kp, Ki, and Kd (Ki = Ti / Kp; Kd = Kp x Td), so as to more accurately obtain the integrated output of the control.

[0048] In step (2), the rate of change of the pneumoperitoneum pressure drop dynamically includes a pressure rapid condition and a pressure slow drop condition. In the pressure rapid condition, based on increasing the Kp and Kd values and simultaneously decreasing the Ki value to adjust the control amount integrated output, in short, increasing the Kp value to rapidly increase the gas flow to inhibit the rapid drop of the pressure, and simultaneously decreasing the integral coefficient such as Ki to avoid the integral link from generating an excessive overshoot in the rapid change process. In the pressure slow drop condition, based on increasing the Ki value and keeping the Kp and Kd values unchanged to adjust the control amount integrated output, that is, when the pneumoperitoneum pressure drop is relatively slow, the integral coefficient Ki can be appropriately increased to make the integral link play a more active role in the long-term pressure adjustment, and simultaneously keeping the proportional coefficient Kp and the differential coefficient Kd at a moderate value to stably increase the gas flow to compensate for the pressure loss. A pneumoperitoneum pressure safety reference value is set, and in the forced negative pressure condition of step (2), the limit safety pneumoperitoneum pressure is greater than or equal to the pneumoperitoneum pressure safety reference value. In short, based on the PID algorithm to control the pressure, the situation that the forced generated negative pressure causes the abdominal cavity pressure to rapidly drop is solved, and a period for normal surgery is still maintained to ensure the normal surgery. In the forced negative pressure condition of step (2), the pressure change of the pneumoperitoneum pressure is divided into a first drop section, a rising section, a second drop section, and a third drop section, wherein the pressure change rates of the three drop sections are V1, V2, and V3 respectively, and V1

[0049] In addition, at the negative pressure closing time of step (2), the pneumoperitoneum pressure constitutes the initial rising stage and the constant rising stage, in which the control amount comprehensive output is changed based on the parameter values of Kd and Ki. After the negative pressure closing, the pneumoperitoneum pressure recovers, and under the action of the insufflation pressure, the pneumoperitoneum pressure starts to rise steadily after the forced negative pressure Pq is closed. The control system continues to monitor the pneumoperitoneum pressure, and according to the pressure rising condition, gradually adjusts the gas flow. When the pneumoperitoneum pressure approaches the preset pressure value, the flow is fine-tuned by the PID algorithm, so that the pneumoperitoneum pressure accurately reaches the preset pressure value, and returns to the normal surgical pneumoperitoneum state. In this process, the PID parameters may need to be adjusted again, for example, the proportional coefficient Kp and the integral coefficient Ki are appropriately reduced, so as to avoid the over-regulation of the pneumoperitoneum pressure. The whole process ensures the smooth change of the pneumoperitoneum pressure, and does not have adverse effects on the surgical operation and the physiological state of the patient.

[0050] Briefly, the control logic of the present embodiment realizes the PID algorithm: the pressure data acquisition and processing of the electric signal of the pressure sensor, and the conversion of the electric signal into corresponding pressure values, so as to obtain accurate real-time pressure information. Among them, the preset pressure is p_exp, and the current pressure value is p_cur. In the control logic, the PID parameters are preset, and according to the design of the pneumoperitoneum machine and the surgical requirements, a set of initial PID parameters (such as the proportional coefficient Kp=0.2, the integral coefficient Ki=0.1, and the differential coefficient Kd=0.01) are preset. The initial values of these parameters are determined through simulation experiments and clinical experience data.

[0051] PID algorithm calculation process: when the preset pressure p exp and the current pressure p cur are monitored, and the preset pressure p exp > the current pressure p cur, the PID algorithm is started to regulate the insufflation pressure. Proportional link (P): calculate the deviation value ERR P between the current insufflation pressure and the preset insufflation pressure, multiply the deviation value by the proportional coefficient Kp to obtain the proportional control quantity. The role of the proportional control quantity is to quickly adjust the gas flow according to the size of the deviation. The larger the deviation, the greater the adjustment range. For example, if the insufflation pressure is much lower than the preset value, the proportional control quantity will make the flow regulating valve quickly increase the opening degree and increase the gas flow ERR P = p exp - p cur; integral link (I): the integral operation is performed on the deviation value ERR P to obtain ERR I, and then multiplied by the integral coefficient Ki to obtain the integral control quantity. The role of the integral control quantity is to eliminate the steady-state error of the system. When there is a persistent deviation in the insufflation pressure, the integral link will gradually accumulate, so that the gas flow is continuously adjusted until the deviation is eliminated. ERR I = ERR I + ERR P; (the initial value of ERR I is 0); differential link (D): the differential operation is performed on the deviation value ERR P to obtain ERR D, and then multiplied by the differential coefficient Kd to obtain the differential control quantity. The role of the differential control quantity is to adjust the gas flow in advance according to the trend of the insufflation pressure change. When it is detected that the insufflation pressure decreases rapidly, the differential control quantity will make the flow regulating valve increase the opening degree faster to cope with the possible greater pressure loss. ERR D = ERR D - ERR P; (the initial value of ERR D is 0); comprehensive control output: add the proportional, integral and differential control quantities to obtain the final control output value, which is used to control the opening degree of the flow regulating valve, so as to adjust the gas flow. If the comprehensive control output value increases, the opening degree of the flow regulating valve increases, the gas flow increases, and then the insufflation pressure increases. Final output result = Kp * (ERR P) + Ki * (ERR I) + Kd * (ERR D).

[0052] Further, the PID parameters are adjusted according to the pressure change trend. The PID parameters are dynamically adjusted by analyzing the pressure change trend. When the program identifies different pressure change trends through the PID algorithm fitting results, different PID parameter combinations are used. Specifically, for the condition of rapid pressure drop trend, when the pressure drop trend is detected (for example, the pressure drops by more than a certain threshold value within a short period of time, such as a flow rate of 20, a threshold value of 10^(-8)), the proportional coefficient and the differential coefficient are appropriately increased, such as Kp=0.3 and Kd=0.012, to rapidly increase the gas flow rate and suppress the rapid pressure drop. At the same time, the integral coefficient is appropriately reduced, such as Ki=0.09, to avoid excessive overshoot of the integral link in the rapid change process. For the condition of slow pressure drop trend, when the pressure drop is relatively slow, the integral coefficient can be appropriately increased, such as Ki=0.15, to make the integral link play a more active role in long-term pressure adjustment. At the same time, the proportional coefficient Kp=0.2 and the differential coefficient Kd=0.01 are maintained at an appropriate value to stably increase the gas flow rate to compensate for the pressure loss. The pressure in the surgical period is maintained stable. When the forced negative pressure Pq exists and the forced negative pressure Pq>injection pressure Pz, the gas flow rate is adjusted in real time by repeatedly calculating and adjusting the PID algorithm and parameters to maintain the pressure in a range that can ensure normal operation of the surgery. This range should be determined according to the type of surgery and the patient's condition, and generally should ensure that the abdominal cavity has enough space for surgical instruments to operate, while avoiding harm to the patient due to excessively high or low pressure. After the negative pressure is closed, the pressure is restored under the action of the injection pressure. The control system continues to monitor the pressure, and gradually adjusts the gas flow rate according to the pressure rise. When the pressure approaches the preset pressure value, the flow rate is finely adjusted by the PID algorithm to accurately reach the preset pressure value and restore to the normal surgical pneumoperitoneum state. In this process, the PID parameters may need to be adjusted again, such as appropriately reducing the proportional coefficient Kp and the integral coefficient Ki to avoid overshoot of the pressure. The whole process ensures the smooth change of the pressure and does not adversely affect the surgical operation and the patient's physiological state.

[0053] In summary, after adopting the gas pressure stable regulation process, first, the control quantity is obtained based on the PID algorithm, wherein the proportional, integral and differential three control quantities are fitted to form the control quantity comprehensive output; second, the parameter value size of Kp, Ki and Kd is dynamically adjusted based on the change rate of the gas pressure drop, so as to dynamically adjust the output control quantity in real time, so that the gas pressure is reduced based on the cooperation of the gas injection amount and the gas injection speed in the forced negative pressure condition, and at the same time, the pressure difference size change is completed based on the forced negative pressure to achieve the negative pressure processing target in the required time, and after the gas pressure drops to the limit safety gas pressure, the negative pressure is closed, and based on the parameter value reduction of Kd and Ki, the gas pressure is continuously increased in the control quantity comprehensive output until p_exp=p_cur, therefore, on the one hand, the control quantity comprehensive output is dynamically adjusted based on the PID algorithm to solve the problem of gas space failure in the condition that the forced negative pressure causes the abdominal cavity pressure to drop rapidly, so that the gas pressure meets the use demand (for example, maintaining the period that can normally operate to ensure normal operation of the operation), and at the same time, the negative pressure device can complete the negative pressure processing target in the required time and the change pressure difference condition; on the other hand, in the process of forced negative pressure and negative pressure closing, the formed gas pressure rises stably, and there is no gas shortage or excessive gas supply, so that it works on the basis of normal artificial pneumoperitoneum, and will not cause damage to the human body, nor will it cause the danger caused by sudden rise of the gas pressure, and prevent complications such as high pneumoperitoneum syndrome; thirdly, the gas flow is rapidly adjusted based on the proportional control quantity, the greater the deviation, the greater the adjustment range, for example, if the gas pressure is far below the preset value, the proportional control quantity will make the flow regulating valve quickly increase the opening degree and increase the gas flow; the integral control quantity is used to eliminate the steady-state error of the system, when there is a persistent deviation in the gas pressure, the integral element will gradually accumulate, so that the gas flow is continuously adjusted until the deviation is eliminated; the differential control quantity is used to adjust the gas flow in advance, that is, the gas flow is adjusted in advance according to the trend of the gas pressure change, when the gas pressure drop speed is detected to be accelerated, the differential control quantity will make the flow regulating valve increase the opening degree faster to cope with the possible greater pressure loss; the final control output value is obtained by adding the proportional, integral and differential three control quantities, which is used to control the opening degree of the flow regulating valve, so as to adjust the gas flow, if the comprehensive control output value increases, the flow regulating valve opening degree increases, the gas flow increases, and then the gas injection pressure increases; fourthly, in the pressure slow drop condition, the control quantity comprehensive output is adjusted based on increasing the Ki value and keeping the Kp and Kd values unchanged, that is, when the gas pressure drops slowly, the integral coefficient Ki can be appropriately increased, so that the integral element plays a more active role in long-term pressure adjustment, and at the same time, the proportional coefficient Kp and the differential coefficient Kd are kept at a moderate value, so as to stably increase the gas flow to compensate the pressure loss;The fifth aspect controls the pressure based on the PID algorithm, solves the situation that the forced negative pressure causes the abdominal cavity pressure to rapidly decrease, still maintains a period that can normally operate, and ensures normal operation of the surgery. The sixth aspect realizes relatively stable slow decrease (avoiding sharp decrease) of the pneumoperitoneum pressure under forced negative pressure based on the combination mode of three-section decrease and recovery section, and performs the required negative pressure processing under the multi-section negative pressure condition. Therefore, under the premise of completing the negative pressure processing target, the artificial pneumoperitoneum is not invalidated due to the sharp decrease of the negative pressure. At the same time, when the negative pressure is initially formed, the injection amount and injection speed of the recovery section are greater than the negative pressure extraction amount and extraction speed of the first decrease section, so as to avoid the situation of sudden decrease of the pressure and the situation that the human body is damaged due to the instantaneous excessive injection of the airflow. When the forced negative pressure is not performed, the pressure formed by the pneumoperitoneum is the original pressure value, the maximum value of the pneumoperitoneum pressure of the recovery section is less than or equal to the original pressure value, and the human body is avoided from being damaged due to the instantaneous excessive injection of the airflow. The seventh aspect includes the initial increase section and the constant increase section when the negative pressure is closed. In the constant increase section, the control amount comprehensive output is changed based on the decrease of the parameter values of Kd and Ki. The pneumoperitoneum pressure is recovered after the negative pressure is closed. After the forced negative pressure Pq is closed, the pneumoperitoneum pressure starts to stably rise under the action of the gas injection pressure. The control system continues to monitor the pneumoperitoneum pressure, gradually adjusts the gas flow according to the pressure rise situation, and accurately adjusts the flow through the PID algorithm when the pneumoperitoneum pressure approaches the preset pressure value, so as to accurately make the pneumoperitoneum pressure reach the preset pressure value and recover to the normal surgery pneumoperitoneum state. In this process, the PID parameters may need to be adjusted again, for example, the proportional coefficient Kp and the integral coefficient Ki are appropriately reduced, so as to avoid the over-regulation of the pneumoperitoneum pressure. The whole process needs to ensure that the change of the pneumoperitoneum pressure is stable, does not have adverse effects on the operation and physiological state of the patient.

[0054] The above detailed description of the present application is intended to enable a person skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A gas pressure stabilizing type pneumoperitoneum machine suitable for a forced negative pressure working condition, comprising a pneumoperitoneum main machine, a gas supply device, and a negative pressure device, wherein the negative pressure device and the pneumoperitoneum main machine are in communication with a pneumoperitoneum cavity, the gas supply device is in communication with the pneumoperitoneum main machine, and the pneumoperitoneum main machine adjusts the injection or discharge of gas based on the pressure change in the pneumoperitoneum cavity, characterized in that, The gas-tight pressure stabilizing type pneumoperitoneum machine adopts PID algorithm control mode for pressure regulation, wherein when the preset pressure p_exp and the current pressure p_cur are monitored and the preset pressure p_exp>p_cur, the regulation is started and includes the following steps: (1) PID algorithm obtains control amount First, the deviation value ERR_P is calculated, wherein ERR_P=p_exp-p_cur, and the proportional control amount obtained is ERR_P×Kp, and Kp is the proportional coefficient; second, the integral operation is performed on the deviation value ERR_P to obtain ERR_I, and the integral control amount is ERR_I×Ki, and Ki is the integral coefficient; third, the differential operation is performed on the deviation value ERR_P to obtain ERR_D, and the differential control amount is ERR_D×Kd, and Kd is the differential coefficient; finally, the proportional, integral and differential three control amounts are fitted to form the control amount comprehensive output; (2) pressure regulation The parameter value size of Kp, Ki and Kd in step (1) is dynamically adjusted based on the change rate of the pneumoperitoneum pressure drop, so as to dynamically regulate the output control amount in real time, so that the pneumoperitoneum pressure is reduced based on the cooperation of the gas injection amount and the gas injection speed in the forced negative pressure working condition, and the change rate of the pneumoperitoneum pressure drop is reduced, and at the same time, the pressure difference size change based on the forced negative pressure is completed in the required time to achieve the negative pressure processing target, and after the pneumoperitoneum pressure drops to the limit safety pneumoperitoneum pressure, the negative pressure is closed, and the parameter values of Kd and Ki are reduced, and the pneumoperitoneum pressure is continuously increased in the control amount comprehensive output until p_exp=p_cur.

2. The pressure-regulated insufflator for forced negative pressure conditions according to claim 1, characterized in that, The proportional control amount is directly proportional to the ERR_P value.

3. The gas-tight pressure-stabilized insufflator for forced negative pressure working condition according to claim 1, wherein the integral operation formula is: e(τ) = Kp * e(t) + Ki * e(t)dt, where Ki = Ti / Kp, Ti is an integral time constant; e(τ) is an error signal, and is the deviation of the set value and the actual output value; τ is an integral variable, indicating the cumulative process of time from the initial time 0 to the current time t. wherein Ki = Ti / Kp, Ti is an integral time constant; e(τ) is an error signal, and is the deviation of the set value and the actual output value; τ is an integral variable, indicating the cumulative process of time from the initial time 0 to the current time t.

4. The pressure-regulated insufflator for forced negative pressure conditions according to claim 3, characterized in that, e(τ)=r(τ)-y(τ), wherein r(τ) is the set value and y(τ) is the actual output value.

5. The pressure-regulated insufflator for forced negative pressure conditions according to claim 1, characterized in that, The differential operation formula is: wherein Kd = Kp x Td, is a change rate of the error signal with time, reflecting a change trend of the error; Td is a differential time constant.

6. The pressure-regulated insufflator for forced negative pressure conditions according to claim 1, characterized in that, The control amount comprehensive output=Kp×(ERR_P)+Ki×(ERR_I)+Kd×(ERR_D).

7. The pressure-regulated insufflator for forced negative pressure conditions according to claim 1, characterized in that, The change rate of the pneumoperitoneum pressure drop dynamically includes the pressure fast working condition and the pressure slow drop working condition, wherein in the pressure fast working condition, the control amount comprehensive output is adjusted based on increasing the values of Kp and Kd and simultaneously reducing the value of Ki; In the pressure slow drop working condition, the control amount comprehensive output is adjusted based on increasing the value of Ki and keeping the values of Kp and Kd unchanged.

8. The pressure-regulated insufflator for forced negative pressure conditions according to claim 1, characterized in that, The set pneumoperitoneum pressure safety reference value is greater than or equal to the limit safety pneumoperitoneum pressure in the forced negative pressure working condition of step (2).

9. The pressure-regulated insufflator for forced negative pressure conditions according to claim 8, characterized in that, In the forced negative pressure working condition of step (2), the pressure change of the pneumoperitoneum pressure is divided into a first drop segment, a rising segment, a second drop segment and a third drop segment, wherein the pressure change rates of the three drop segments are V1, V2 and V3 respectively, and V1V2V3, and the times of the three drop segments are t1, t2 and t3 respectively, and t1t2t3.

10. The pressure-regulated insufflator for forced negative pressure conditions according to claim 9, characterized in that, The time used in the rising segment is t4, wherein t4t1.

11. The pressure-regulated insufflator for forced negative pressure conditions according to claim 10, characterized in that, When the forced negative pressure is not performed, the pressure formed by the pneumoperitoneum is the original pressure value, and the maximum value of the pneumoperitoneum pressure in the rising segment is less than or equal to the original pressure value.

12. The pressure-regulated insufflator for forced negative pressure conditions according to claim 1, characterized in that, When the negative pressure is closed in step (2), the pneumoperitoneum pressure constitutes a preliminary rising segment and a constant rising segment, wherein in the constant rising segment, the control amount comprehensive output is changed based on the reduction of the parameter values of Kd and Ki.

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