Polyester viscosity control method and device and computer equipment

Abstract

The invention relates to the technical field of chemical production, in particular to a polyester viscosity control method and device and computer equipment.The polyester viscosity control method comprises the steps that the current stirring current and the current liquid level of a polyester reaction kettle are obtained, and fuzzy reasoning is conducted based on the current stirring current and the current liquid level; the viscosity change condition in the reaction kettle can be predicted before the reading of the viscometer changes, so that the pressure in the reaction kettle is controlled in advance, the product viscosity is prevented from being unqualified, the product quality stability in the polyester production process is improved, the personnel operation amount is reduced, and the automation level of the device is improved.

Description

Technical Field

[0001] The invention relates to the technical field of chemical production, and in particular to a method and device for controlling the viscosity of polyester and computer equipment. Background Art

[0002] With the enhancement of environmental awareness, the production of biodegradable plastics has received more and more attention. PBAT (PolybutyleneAdipate-co-Butylene Terephthalate) is one of the most popular and best-used biodegradable materials in the market among biodegradable plastics. The viscosity control of materials in the final polycondensation and thickening polycondensation processes in its production process is extremely critical. The discharge viscosity not only has a great influence on technical indicators such as the product melt index, but also affects the stable operation of the downstream pelletizer. However, there are many factors affecting viscosity, and the viscometer measurement of the discharge pipeline is lagging, and the viscosity is manually controlled by personnel experience. The viscosity index is unstable and the amount of personnel operation is huge. Therefore, there is an urgent need for an automatic control method that can accurately control the viscosity in the polyester production process. Summary of the invention

[0003] In view of this, the present invention provides a method, device and computer equipment for controlling the viscosity of polyester to solve the problem of lag in viscosity control during the polyester production process.

[0004] In a first aspect, the present invention provides a method for controlling polyester viscosity, comprising the following steps: obtaining a current stirring current and a current liquid level of a polyester reactor; performing fuzzy reasoning based on the current stirring current and the current liquid level to obtain a viscosity prediction value; obtaining a preset viscosity setting value; and adjusting the air inlet pressure of the polyester reactor based on the viscosity prediction value and the viscosity setting value.

[0005] The polyester viscosity control method provided by the present invention obtains the current stirring current and the current liquid level of the polyester reactor and performs fuzzy reasoning based on the current stirring current and the current liquid level. It can predict the viscosity change inside the reactor before the viscometer reading changes, and then control the pressure in the reactor in advance to prevent the product viscosity from being unqualified, improve the product quality stability in the polyester production process, reduce the amount of human operation, and improve the automation level of the device.

[0006] In an optional embodiment, fuzzy reasoning is performed based on the current stirring current and the current liquid level to obtain a viscosity prediction value, including: using a triangular membership function to fuzzy process the current stirring current and the current liquid level to obtain two input fuzzy sets; using preset fuzzy rules to perform fuzzy reasoning based on the two input fuzzy sets to obtain an output fuzzy set; using a trapezoidal membership function and a centroid defuzzification method to defuzzify the output fuzzy set to obtain a viscosity prediction value.

[0007] Therefore, the viscosity prediction value can be obtained by using fuzzy reasoning.

[0008] In an optional embodiment, the polyester viscosity control method also includes the following steps: obtaining historical operating data of the polyester reactor, the historical operating data including multiple groups of operating data, each group of operating data including the actual stirring current, actual liquid level and actual viscosity of the polyester reactor at the same time; and determining fuzzy rules using the historical operating data.

[0009] Therefore, the fuzzy rules can be determined based on the historical operating data of the polyester reactor.

[0010] In an optional embodiment, adjusting the air inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value includes: when the viscosity prediction value is greater than a preset first threshold value, increasing the opening of the first valve to increase the air inlet pressure of the polyester reactor; when the viscosity prediction value is less than a preset second threshold value, reducing the opening of the first valve to reduce the air inlet pressure of the polyester reactor; wherein the first threshold value and the second threshold value are determined according to the viscosity setting value.

[0011] That is to say, when the viscosity prediction value differs greatly from the viscosity setting value, that is, the viscosity prediction value is greater than the first threshold value or the viscosity prediction value is less than the second threshold value, the viscosity in the polyester reactor is adjusted by adjusting the air inlet pressure of the reactor so that the viscosity prediction value differs less from the viscosity setting value, that is, the viscosity prediction value is within the range enclosed by the first threshold value and the second threshold value.

[0012] In an optional embodiment, the polyester viscosity control method also includes the following steps: obtaining the actual opening of the first valve; determining whether the actual opening is greater than a preset third threshold; when the actual opening is greater than the third threshold, adjusting the opening of the second valve so that the opening of the first valve is less than or equal to the third threshold.

[0013] That is to say, by adopting the dual valve control, the opening of the second valve is changed so that the opening of the first valve is maintained at an ideal valve opening, thereby ensuring that the first valve has a better regulating ability.

[0014] In the second aspect, the present invention also provides a control device for polyester viscosity, comprising a first acquisition module, a viscosity prediction value determination module, a second acquisition module and a pressure adjustment module; the first acquisition module is used to obtain the current stirring current and the current liquid level of the polyester reactor; the viscosity prediction value determination module is used to perform fuzzy reasoning based on the current stirring current and the current liquid level to obtain the viscosity prediction value; the second acquisition module is used to obtain a preset viscosity setting value; the pressure adjustment module is used to adjust the air intake pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value.

[0015] In a third aspect, the present invention further provides a computer device, comprising a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the method for controlling the viscosity of polyester according to the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0016] In a fourth aspect, the present invention further provides a polyester viscosity control system, comprising a viscosity increasing kettle and the computer device of the third aspect, wherein the viscosity increasing kettle and the computer device are communicatively connected.

[0017] In a fifth aspect, the present invention further provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the polyester viscosity control method of the first aspect or any corresponding embodiment thereof.

[0018] In a sixth aspect, the present invention further provides a computer program product, comprising computer instructions for causing a computer to execute the polyester viscosity control method of the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 Flow chart of a polyester viscosity control method according to an embodiment of the present invention

[0021] Figure 2 is a flow chart of a polyester viscosity control method according to an embodiment of the present invention;

[0022] Figure 3 is a flow chart of another polyester viscosity control method according to an embodiment of the present invention;

[0023] Figure 4 is a schematic structural diagram of a polyester viscosity control system according to an embodiment of the present invention;

[0024] Figure 5 is a flow chart of an example of a polyester viscosity control method according to an embodiment of the present invention;

[0025] Figure 6 is a structural block diagram of a polyester viscosity control device according to an embodiment of the present invention;

[0026] Figure 7is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention;

[0027] Among them, 1. viscosity controller; 2. pressure controller; 3. valve position controller; 4. first valve; 5. second valve; 6. fuzzy reasoning controller. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0029] According to an embodiment of the present invention, an embodiment of a method for controlling the viscosity of polyester is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0030] In this embodiment, a method for controlling the viscosity of polyester is provided, which can be used in computer equipment. Figure 1 : is a flow chart of a polyester viscosity control method according to an embodiment of the present invention, such as Figure 1 As shown, the process includes the following steps:

[0031] Step S101: obtaining the current stirring current and the current liquid level of the polyester reactor.

[0032] like Figure 2 As shown, the viscosity-increasing reactor is provided with a stirring device, IA is the stirring current of the reactor, and a liquid level meter LI is provided on the reactor. Specifically, the liquid level can be collected by the liquid level meter LI provided on the reactor, and the stirring current can be collected by the ammeter provided on the stirring motor.

[0033] Step S102: Perform fuzzy reasoning based on the current stirring current and the current liquid level to obtain a viscosity prediction value.

[0034] Step S103: Obtaining a preset viscosity setting value.

[0035] Specifically, the viscosity setting value that meets the product performance can be obtained based on the design documents and actual operating experience.

[0036] Step S104: adjusting the air inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value.

[0037] The polyester viscosity control method provided in this embodiment obtains the current stirring current and the current liquid level of the polyester reactor and performs fuzzy reasoning based on the current stirring current and the current liquid level. It can predict the viscosity change inside the reactor before the viscometer reading changes, and then control the pressure in the reactor in advance to prevent the product viscosity from being unqualified, improve the product quality stability in the polyester production process, reduce the amount of human operation, and improve the automation level of the device.

[0038] In this embodiment, a method for controlling the viscosity of polyester is provided, which can be used in computer equipment. Figure 2 : is a flow chart of another polyester viscosity control method according to an embodiment of the present invention, such as Figure 2 As shown, the process includes the following steps:

[0039] Step S201: Obtain the current stirring current and current liquid level of the polyester reactor.

[0040] Step S202: Perform fuzzy reasoning based on the current stirring current and the current liquid level to obtain a viscosity prediction value.

[0041] In an optional implementation, performing fuzzy reasoning based on the current stirring current and the current liquid level to obtain a viscosity prediction value includes the following steps:

[0042] Step S2021: Use the triangle membership function to perform fuzzy processing on the current stirring current and the current liquid level to obtain two input fuzzy sets.

[0043] Step S2022: Perform fuzzy reasoning based on the two input fuzzy sets using preset fuzzy rules to obtain an output fuzzy set.

[0044] Step S2023: Defuzzify the output fuzzy set using the trapezoidal membership function and the centroid defuzzification method to obtain a viscosity prediction value.

[0045] Specifically, the fuzzy rules can be obtained by the following method: obtaining historical operation data of the polyester reactor, the historical operation data includes multiple groups of operation data, each group of operation data includes the actual stirring current, actual liquid level and actual viscosity of the polyester reactor at the same time; using the historical operation data to determine the fuzzy rules.

[0046] That is to say, the DOS system collects the reactor stirring current and reactor liquid level time series data of different reactor discharge viscosities within half a year to obtain historical operation data. For example, the actual stirring current of the polyester reactor can be collected by the ammeter set on the stirring motor; the actual liquid level of the polyester reactor can be collected by the level meter set on the reactor; the actual viscosity of the polyester reactor can be collected by the viscometer set on the reactor outlet pipeline.

[0047] The actual stirring current, actual liquid level and actual viscosity of the polyester reactor are detected in real time. The above data are read through DOS, and the actual stirring current and actual liquid level are selected as the input variables of the fuzzy controller, and the actual viscosity is selected as the target variable of the module controller. The stirring current I, liquid level L and viscosity Vi are established. 预 Fuzzy sets and domains.

[0048] Using trigonometric functions as membership functions for fuzzification, we get two fuzzy sets. For the output variable (material viscosity, the domain is set to [0,1], the output fuzzy set is {NB, NM, NS, ZE, PS, PM, PB}, fuzzy reasoning rules are established, reasoning is performed according to the fuzzy rules, and the fuzzy output set is obtained. The fuzzy output set is defuzzified using the trapezoidal membership function and the centroid defuzzification method to obtain the output value of the predicted material viscosity.

[0049] Specifically, stirring current I, liquid level L and material viscosity Vi 预 The fuzzy subset linguistic variables are defined as follows:

[0050] I={NB, NM, NS, ZE, PS, PM, PB};

[0051] L={NB, NM, NS, ZE, PS, PM, PB};

[0052] Vi 预 ={NB, NM, NS, ZE, PS, PM, PB};

[0053] I, L, Vi 预 The membership function curves are all trigonometric functions.

[0054] The fuzzy rules are defined as follows:

[0055]

[0056]

[0057] The accuracy of fuzzy inference viscosity was tested using test set samples, and the average deviation of inference prediction was 0.1%, which met the process requirements.

[0058] Step S203: Obtaining a preset viscosity setting value.

[0059] Step S204: adjusting the air inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value.

[0060] The polyester viscosity control method provided in this embodiment obtains the current stirring current and the current liquid level of the polyester reactor and performs fuzzy reasoning based on the current stirring current and the current liquid level. It can predict the viscosity change inside the reactor before the viscometer reading changes, and then control the pressure in the reactor in advance to prevent the product viscosity from being unqualified, improve the product quality stability in the polyester production process, reduce the amount of human operation, and improve the automation level of the device.

[0061] In this embodiment, a method for controlling the viscosity of polyester is provided, which can be used in computer equipment. Figure 3 is a flow chart of another polyester viscosity control method according to an embodiment of the present invention, Figure 5 : is a flow chart of an example of a polyester viscosity control method according to an embodiment of the present invention. Figure 3 and Figure 5 As shown, the process includes the following steps:

[0062] Step S301: Obtain the current stirring current and current liquid level of the polyester reactor.

[0063] Step S302: Perform fuzzy reasoning based on the current stirring current and the current liquid level to obtain a viscosity prediction value.

[0064] Step S303: Obtain a preset viscosity setting value.

[0065] Step S304: adjusting the air inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value.

[0066] In an optional embodiment, adjusting the inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value comprises the following steps:

[0067] Step S3041: when the viscosity prediction value is greater than a preset first threshold, the opening of the first valve is increased to increase the air inlet pressure of the polyester reactor, wherein the first threshold is determined according to the viscosity setting value.

[0068] Step S3042: When the viscosity prediction value is less than a preset second threshold value, the opening of the first valve is reduced to reduce the air inlet pressure of the polyester reactor, wherein the second threshold value is determined according to the viscosity setting value.

[0069] Figure 4 Schematic diagram of the structure of a polyester viscosity control system according to an embodiment of the present invention. Figure 4As shown, the viscosity control system of polyester is provided with a viscosity controller 1, a pressure controller 2, a valve position controller 3 and a fuzzy reasoning controller 6. The viscosity-increasing reactor is provided with a stirring device, IA is the stirring current of the reactor, a liquid level gauge LI is provided on the reactor, and the outlet pump frequency is controlled according to the liquid level. The reactor outlet is provided with a viscosity controller 1, and the reactor pressure is adjusted according to the viscosity change. The reactor gas phase main pipeline is provided with a pressure controller 2, and the main pipe is connected to two branch pipes, which are respectively provided with a first valve 4 and a second valve 5. The system pressure is adjusted by changing the opening of the first valve 4 and the second valve 5, so that the first valve 4 is maintained at the desired opening. Among them, the first valve 4 and the second valve 5 are respectively located in the two branch pipes. Since the diameter of the branch pipe where the first valve 4 is located is larger than the diameter of the branch pipe where the second valve 5 is located, the regulating capacity of the first valve 4 is greater than the regulating capacity of the second valve. The first valve 4 can be called a small valve, and the second valve 5 can be called a large valve. The valve position controller takes the opening of the first valve 4 as the actual value PV, and changes the opening of the second valve 5 through the output of the valve position controller, so that the opening of the first valve 4 is maintained in the ideal range.

[0070] For example, the viscosity setting value is Vi 设 Indicates that the target fluctuation range of the viscosity setting value is Vi 设 ±a, a is the material viscosity in Vi 设 The expected change in the center is Vi. 设 +a is the first threshold, Vi 设 -a is the second threshold.

[0071] When Vi 预 Greater than Vi 设 +a, the output of the viscosity controller increases under the PID control, and then the set value of the pressure controller of the auxiliary regulating loop increases. Under the action of the PID of the auxiliary regulating loop, the opening of the small vacuum valve is closed, so that the system pressure increases; similarly, when Vi 预 Less than Vi 设 -a, under the action of PID control, the output of the viscosity controller decreases, and then the set value of the pressure controller of the auxiliary regulating loop decreases. Under the action of the PID of the auxiliary regulating loop, the opening of the small vacuum valve is widened to reduce the system pressure.

[0072] like Figure 4 As shown in the figure, the viscosity obtained by fuzzy reasoning is used as the viscosity prediction value of the viscosity controller VICAS, the material viscosity index required by the design document is used as the viscosity setting value, the viscosity controller output MV is used as the setting value SV of the reactor pressure controller, and the reactor pressure is adjusted according to the deviation between the viscosity prediction value obtained by fuzzy reasoning and the material viscosity index required by the design document. If the viscosity prediction value is greater than the viscosity setting value and exceeds the expected range of change, the reactor pressure is increased; if the viscosity prediction value is less than the viscosity setting value and exceeds the expected range of change, the reactor pressure is reduced.

[0073] For example, by comparing the deviation between the predicted material viscosity and the set material viscosity, the pressure control set value of the system is changed under the action of PID control. Specifically, the reactor pressure controller PIC adjusts the opening of the gas phase pipeline small valve according to the deviation between the set pressure and the actual pressure. If the set pressure is higher than the actual pressure, the opening of the gas phase pipeline small valve is reduced; if the set pressure is lower than the actual pressure, the opening of the gas phase pipeline small valve is increased.

[0074] Furthermore, after step S3041 or step S3042, the following steps are also included: obtaining the actual opening of the first valve; determining whether the actual opening is greater than a preset third threshold; when the actual opening is greater than the third threshold, adjusting the opening of the second valve so that the opening of the first valve is less than or equal to the third threshold.

[0075] That is to say, in order to ensure that the vacuum valve has a good adjustment ability, the valve position controller 3 uses the output of the pressure controller as PV and the desired vacuum valve opening of 60% as SV. The output MV of the valve position control acts on the large vacuum valve. When the opening of the small vacuum valve is greater than 60%, the output of the valve position controller 3 increases under the action of PID, and the opening of the large vacuum valve slowly increases, so that the opening of the small vacuum valve gradually returns to 60%; when the opening of the small vacuum valve is less than 60%, the output of the valve position controller 3 decreases under the action of PID, and the opening of the large vacuum valve slowly decreases, so that the opening of the small vacuum valve gradually returns to 60%.

[0076] That is to say, the pressure control adopts dual valve control. Under the action of the valve position controller 3, by changing the opening of the second valve, the opening of the first valve is maintained at an ideal valve opening, such as 60%, thereby ensuring that the first valve has a better adjustment ability.

[0077] The polyester viscosity control method provided in this embodiment has the following advantages: (1) It overcomes the measurement lag problem of the existing viscometer, predicts the viscosity change before the viscometer detects the viscosity change, and timely adjusts the system pressure without manual intervention, making the material viscosity control more stable; (2) The system pressure control adopts valve position control, and the first valve is always in the optimal adjustment range under the coordinated action of the first valve and the second valve, so that the system pressure control is more stable, which has a favorable effect on the stability of viscosity and the stable operation of the downstream pelletizer.

[0078] In this embodiment, a device for controlling the viscosity of polyester is also provided, which is used to implement the above-mentioned embodiments and preferred implementations, and the descriptions that have been made will not be repeated. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0079] This embodiment provides a control device for polyester viscosity, such as Figure 6 As shown, including:

[0080] The first acquisition module 601 is used to acquire the current stirring current and the current liquid level of the polyester reactor.

[0081] The viscosity prediction value determination module 602 is used to perform fuzzy reasoning according to the current stirring current and the current liquid level to obtain the viscosity prediction value.

[0082] The second acquisition module 603 is used to acquire a preset viscosity setting value.

[0083] The pressure adjustment module 604 is used to adjust the air inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value.

[0084] In some optional embodiments, the viscosity prediction value determination module 602 is specifically used to: use a triangular membership function to fuzzy process the current stirring current and the current liquid level to obtain two input fuzzy sets; use preset fuzzy rules to perform fuzzy reasoning based on the two input fuzzy sets to obtain an output fuzzy set; use a trapezoidal membership function and a centroid defuzzification method to defuzzify the output fuzzy set to obtain a viscosity prediction value.

[0085] In some optional embodiments, the polyester viscosity control device further includes a fuzzy rule determination module. The fuzzy rule determination module is used to obtain historical operation data of the polyester reactor, the historical operation data includes multiple groups of operation data, each group of operation data includes the actual stirring current, actual liquid level and actual viscosity of the polyester reactor at the same time; and determine the fuzzy rules using the historical operation data.

[0086] In some optional embodiments, the pressure adjustment module 604 is specifically used to: when the viscosity prediction value is greater than a preset first threshold value, increase the opening of the first valve to increase the intake pressure of the polyester reactor; when the viscosity prediction value is less than a preset second threshold value, reduce the opening of the first valve to reduce the intake pressure of the polyester reactor; wherein the first threshold value and the second threshold value are determined according to the viscosity setting value.

[0087] In some optional embodiments, the pressure adjustment module 604 is also used to: obtain the actual opening of the first valve; determine whether the actual opening is greater than a preset third threshold; when the actual opening is greater than the third threshold, adjust the opening of the second valve so that the opening of the first valve is less than or equal to the third threshold.

[0088] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0089] The polyester viscosity control device in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0090] The embodiment of the present invention also provides a computer device having the above Figure 6 The control device for the viscosity of polyester shown in the figure, wherein the viscosity controller 1, the pressure controller 2, the valve position controller 3 and the fuzzy inference controller 6 are all computer devices.

[0091] The embodiment of the present invention further provides a polyester viscosity control system, comprising a viscosity increasing kettle and the above-mentioned computer device, wherein the viscosity increasing kettle and the computer device are communicatively connected.

[0092] See also Figure 7 , Figure 7 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Figure 7 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 7 A processor 10 is taken as an example.

[0093] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0094] The memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method shown in the above embodiment.

[0095] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0096] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0097] The computer device also includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means. Figure 7 The example of connecting through bus is taken in the following.

[0098] The input device 30 can receive input digital or character information, and generate key signal input related to the user settings and function control of the computer device, such as a touch screen, a keypad, a mouse, a track pad, a touch pad, an indicator bar, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED) and a tactile feedback device (e.g., a vibration motor), etc. The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display and a plasma display. In some optional embodiments, the display device can be a touch screen.

[0099] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0100] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0101] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for controlling the viscosity of polyester, characterized in that: include: Get the current stirring current and current liquid level of the polyester reactor; Perform fuzzy reasoning according to the current stirring current and the current liquid level to obtain a viscosity prediction value; Get the preset viscosity setting value; The air inlet pressure of the polyester reactor is adjusted according to the viscosity prediction value and the viscosity setting value.

2. The method according to claim 1, characterized in that The fuzzy reasoning based on the current stirring current and the current liquid level to obtain the viscosity prediction value includes: Using a triangular membership function to perform fuzzy processing on the current stirring current and the current liquid level, two input fuzzy sets are obtained; Performing fuzzy reasoning based on the two input fuzzy sets using preset fuzzy rules to obtain an output fuzzy set; The output fuzzy set is defuzzified using a trapezoidal membership function and a centroid defuzzification method to obtain the viscosity prediction value.

3. The method according to claim 2, characterized in that Also includes: Acquiring historical operation data of the polyester reactor, wherein the historical operation data includes multiple groups of operation data, each group of operation data includes an actual stirring current, an actual liquid level, and an actual viscosity of the polyester reactor at the same time; The fuzzy rules are determined using the historical operating data.

4. The method according to claim 1, characterized in that The step of adjusting the air inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value comprises: When the predicted viscosity value is greater than a preset first threshold value, the opening of the first valve is increased to increase the air inlet pressure of the polyester reactor; When the viscosity prediction value is less than a preset second threshold value, the opening of the first valve is reduced to reduce the air inlet pressure of the polyester reactor; The first threshold and the second threshold are determined according to the viscosity setting value.

5. The method according to claim 4, characterized in that Also includes: Obtaining an actual opening of the first valve; Determining whether the actual opening is greater than a preset third threshold; When the actual opening is greater than the third threshold, the opening of the second valve is adjusted so that the opening of the first valve is less than or equal to the third threshold.

6. A device for controlling the viscosity of polyester, characterized in that: include: The first acquisition module is used to obtain the current stirring current and the current liquid level of the polyester reactor; A viscosity prediction value determination module, used for performing fuzzy reasoning according to the current stirring current and the current liquid level to obtain a viscosity prediction value; A second acquisition module is used to acquire a preset viscosity setting value; A pressure adjustment module is used to adjust the air inlet pressure of the polyester reactor according to the viscosity prediction value and the viscosity setting value.

7. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are connected to communicate with each other, the memory stores computer instructions, and the processor executes the polyester viscosity control method according to any one of claims 1 to 5 by executing the computer instructions.

8. A polyester viscosity control system, comprising a viscosity increasing kettle and the computer device according to claim 7, wherein the viscosity increasing kettle and the computer device are communicatively connected.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the polyester viscosity control method according to any one of claims 1 to 5.

10. A computer program product, characterized in that The method comprises computer instructions for causing a computer to execute the polyester viscosity control method according to any one of claims 1 to 5.

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