Plasma activated water preparation system based on fuzzy PID adaptive temperature and power matching cooperative control

Abstract

The invention discloses a plasma activated water preparation system based on fuzzy PID (Proportion Integration Differentiation) adaptive temperature and power matching cooperative control. The plasma activated water preparation system comprises a human-computer interface, a main controller, a temperature / power sensor, a parallel double fuzzy PID controller, an intelligent coordinator, a power / temperature actuator and a plasma reaction machine, a temperature / power sensor sends a water body temperature Tfb and a discharge power Pfb to a main controller in real time, a temperature fuzzy PID controller and a power fuzzy PID controller output suggested powers Ut and Up, an intelligent coordinator outputs a final power instruction and a cooling control signal after arbitration according to a state machine that Tfb is smaller than or equal to Tset normal power, Tfb is larger than Tset and Pfb is larger than Pmin and power is preferentially reduced, and Tfb is larger than Tset and Pfb is smaller than or equal to Pmin and is forcibly cooled. And the power actuator continuously adjusts the discharge power according to the discharge power, and the temperature actuator implements auxiliary heat dissipation, so that the water temperature is accurately locked in the optimal active matter generation interval under the nonlinear and time-varying working conditions, the discharge intensity is ensured not to be lower than Pmin, and high-activity, high-energy-efficiency, continuous and stable plasma activated water preparation is realized.

Description

Technical Field

[0001] This invention relates to the field of plasma technology and intelligent control, and more particularly to a plasma-activated water preparation system based on fuzzy PID adaptive temperature and power matching co-control. Background Technology

[0002] Plasma-activated water is a functional liquid rich in reactive oxygen and nitrogen species (such as hydrogen peroxide and nitrite) produced through the interaction of atmospheric pressure cold plasma with aqueous solution. It has significant applications in biomedicine, food processing, and agriculture. During the plasma-water reaction, some of the discharge energy is converted into heat, causing the system temperature to rise. Studies have shown that the formation and stability of active substances are highly dependent on the reaction temperature: at too low a temperature, the plasma-water reaction rate decreases, resulting in insufficient formation of active substances; at too high a temperature, key components such as hydrogen peroxide decompose more rapidly, and the steady-state concentration of nitrite also changes, ultimately leading to a significant decrease in the activity of the activated water. Therefore, precise control of the reaction temperature is a crucial factor in ensuring the efficient formation and stability of active substances.

[0003] Existing technologies mainly control reaction temperature by adjusting discharge power or optimizing heat dissipation structures, but these methods have significant limitations. For example, the patent with application number 202510066179.9 improves the efficiency of active material generation through a low starting voltage design, but it does not solve the problem of temperature rise caused by energy conversion into heat. The patent with application number 202110159128.2 adopts an integrated dual-cycle structure to enhance heat dissipation, which improves system integration, but fails to achieve dynamic coordinated control of power and temperature.

[0004] A more common problem is that traditional control methods (such as fixed-parameter PID) treat power and temperature as independent variables. When the temperature exceeds the limit, simply reducing the power can easily lead to insufficient discharge intensity, causing the generation of active substances to be interrupted. Conversely, if only high power is maintained, it can lead to temperature runaway and decomposition of active substances. This contradiction between the lag and nonlinearity of the control makes it difficult for the system to operate stably under dynamic conditions (such as water flow fluctuations and changes in ambient temperature), ultimately affecting the activity stability and energy efficiency ratio of the activated water. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a plasma-activated water preparation system based on fuzzy PID adaptive temperature and power matching co-control. This invention employs a parallel dual-fuzzy PID control architecture, enabling intelligent coordination between temperature and power control. When the temperature exceeds the optimal range, the system automatically determines whether to adopt an optimized strategy of reducing power or initiating auxiliary cooling, ensuring sufficient plasma discharge intensity is maintained while controlling the temperature, thus guaranteeing efficient generation of active substances. Through adaptive coordinated control of temperature and power, the contradiction between active substance concentration, reaction temperature, and preparation energy efficiency is effectively resolved, achieving intelligent preparation of highly active and highly stable plasma-activated water.

[0006] The technical means employed in this invention are as follows: A plasma-activated water preparation system based on fuzzy PID adaptive temperature and power matching co-control includes: a main controller, a temperature sensor, a power sensor, a temperature actuator, a human-machine interface, a power actuator, and a plasma reactor, wherein: The temperature sensor has its probe end immersed in the water of the plasma reactor and is connected to the analog input port of the main controller via a shielded cable to continuously provide a water temperature feedback signal T_fb. The power sensor has its sampling end connected in series in the power supply circuit of the plasma reactor, and its signal output end connected to the digital input port of the main controller via the I²C bus to continuously provide the discharge power feedback signal P_fb. The human-machine interface is provided with at least an asynchronous serial communication port for sending temperature setpoint T_set, power setpoint P_set and minimum power protection value P_min to the main controller, and receiving the measured temperature T_fb and measured power P_fb back from the main controller in real time. The main controller integrates a temperature fuzzy PID controller, a power fuzzy PID controller, and an intelligent coordinator, and interconnects these components in parallel via an internal data bus. The input terminal of the temperature fuzzy PID controller is connected to the output terminal of the temperature sensor, and the output terminal of the temperature fuzzy PID controller is connected to the intelligent coordinator via an internal bus to output the temperature-side suggested power U_t. The input terminal of the power fuzzy PID controller is connected to the output terminal of the power sensor, and the output terminal of the power fuzzy PID controller is connected to the intelligent coordinator via an internal bus to output the power-side suggested power U_p. The first output of the intelligent coordinator is connected to the control terminal of the power actuator via a PWM pin, and its second output is connected to the control terminal of the temperature actuator via a MOSFET or PWM pin. This is used to output the final power command P_final and the cooling control signal according to the following state machine logic: When T_fb≤T_set, the normal power output mode is adopted, the output P_final=U_t is displayed and the auxiliary cooling is turned off; When T_fb > T_set and P_fb > P_min, the normal power output mode is adopted, the output P_final = U_t is displayed and the auxiliary cooling is turned off; When T_fb > T_set and P_fb ≤ P_min, the forced cooling mode is adopted, P_final = P_min is output and auxiliary cooling is started; The power actuator has its power input terminal connected to an external DC bus and its high-voltage output terminal electrically connected to the discharge electrode of the plasma reactor, and is used to continuously adjust the discharge power according to the final power command P_final. The temperature actuator, whose cooling end or air-cooled outlet is thermally coupled to the water body of the plasma reactor (110), is used to implement forced heat dissipation according to the cooling control signal; The plasma reactor has an inlet connected to an external water source to be treated, an outlet that outputs highly active plasma-activated water, and a discharge electrode that receives high-voltage electrical energy from a power actuator, thereby generating active species in the water.

[0007] Furthermore, the temperature sensor includes a high-precision platinum resistance temperature sensor, which is used to convert the non-electrical quantity temperature of the reaction system into a standard electrical signal and provide accurate and continuous feedback information for the temperature fuzzy PID controller, forming the starting point of the temperature control closed loop.

[0008] Furthermore, the power sensor includes an integrated AC power sensor, which is used to achieve high-precision, isolated measurement of plasma discharge power and to provide a direct feedback signal reflecting the magnitude of energy input for the power fuzzy PID controller and the intelligent coordinator. This is an important basis for power control closed-loop and system collaborative decision-making.

[0009] Furthermore, when the power sensor is an analog output type, the main controller uses an ADC to acquire the data; when the power sensor is a digital type, the main controller uses an SPI or I2C interface to read the data, thereby obtaining the real-time power value P_fb.

[0010] Furthermore, the main controller is connected to the drive circuit in the power actuator to precisely control the on / off state of the power switching device, thereby adjusting the plasma discharge power; the main controller is connected to the drive circuit of the temperature actuator through a general-purpose input / output port or another PWM channel to control the start / stop and speed adjustment of the cooling fan or the thermoelectric cooler.

[0011] Furthermore, the main controller's internal memory stores control algorithms, enabling the microcontroller to implement a parallel dual-fuzzy PID control algorithm and intelligent coordinator decision logic. Under algorithm control, the microcontroller executes the calculation processes of the temperature fuzzy PID controller and the power fuzzy PID controller in parallel, and then runs the state machine decision logic of the intelligent coordinator, ultimately generating control commands for the power actuator and the temperature actuator.

[0012] Furthermore, the temperature fuzzy PID controller is used to adaptively adjust the control strategy according to the temperature deviation and its trend, and output a preliminary power demand signal. The temperature fuzzy PID controller internally includes fuzzy subsets, fuzzy rules, fuzzy inference and defuzzification interfaces. The input of the temperature fuzzy PID controller is the temperature error T_e and its rate of change T_ec, where T_e is calculated from the preset temperature setpoint T_set and the real-time temperature T_fb. The output is a suggested power value U_t for temperature control.

[0013] Furthermore, the power fuzzy PID controller operates in parallel with the temperature fuzzy PID controller to adaptively adjust the control strategy based on the power deviation and its trend, and output a preliminary power demand signal. The power fuzzy PID controller internally includes fuzzy subsets, fuzzy rules, fuzzy inference, and defuzzification interfaces. The input of the power fuzzy PID controller is the power error P_e and its rate of change P_ec, where P_e is calculated from the preset power setpoint P_set and the real-time power value P_fb. The output is a power suggestion U_p.

[0014] Furthermore, the temperature actuator is a physical actuator used to assist in temperature control. The control terminal of the temperature actuator is connected to the MOSFET or PWM output pin of the main controller and receives start / stop and speed adjustment commands from the intelligent coordinator. The active terminal of the temperature actuator, such as the air outlet of a fan or the cold end of a semiconductor cooling chip, points to or contacts the water body of the plasma-activated water. When the system enters the forced cooling mode, it starts according to the command and performs forced heat dissipation with adjustable intensity, thereby suppressing the rise in temperature of the reaction system when the power is locked at P_min.

[0015] Furthermore, the power actuator is an execution device for adjusting the plasma discharge power. Its control terminal is connected to the output terminal of the main controller to receive PWM control signals and realize continuous and precise control of the discharge power of the plasma reactor according to the received PWM control signals.

[0016] Compared with the prior art, the present invention has the following advantages: 1. By synergistically controlling temperature and power, the system always maintains the temperature within the optimal range where the active substances are most stable, while ensuring that the power is not lower than the minimum level required to generate active substances, thereby guaranteeing the high activity of the produced activated water.

[0017] 2. This invention employs a fuzzy PID algorithm, whose parameters can be adaptively adjusted, overcoming the shortcomings of traditional PID in controlling nonlinear systems. The system exhibits strong robustness to changes in internal parameters and external disturbances, with fast response, small overshoot, and high steady-state accuracy.

[0018] 3. This invention introduces a coordinator, enabling the system to select the most reasonable control strategy—whether to reduce power or activate cooling—based on different operating conditions. This represents a shift from simple single-variable control to intelligent collaborative decision-making across multiple variables. In most cases, the system prioritizes reducing power for cooling, resulting in greater energy savings. Auxiliary cooling is only activated when necessary, avoiding energy waste. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a block diagram of the system structure of the present invention.

[0021] Figure 2 This is a schematic diagram of the dual fuzzy PID controller of the system of the present invention.

[0022] Figure 3 This is a flowchart of the system operation of the present invention.

[0023] In the diagram: 101, Temperature sensor; 102, Main controller; 103, Temperature fuzzy PID controller; 104, Power fuzzy PID controller; 105, Power sensor; 106, Intelligent coordinator; 107, Temperature actuator; 108, Human-machine interface; 109, Power actuator; 110, Plasma reactor. Detailed Implementation

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0027] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0028] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0029] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0030] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0031] like Figure 1 As shown, this invention provides a plasma-activated water preparation system based on fuzzy PID adaptive temperature and power matching co-control, comprising: a main controller 102, a temperature sensor 101, a power sensor 105, a temperature actuator 107, a human-machine interface 108, a power actuator 109, and a plasma reactor 110, wherein: The temperature sensor 101 has its detection end immersed in the water of the plasma reactor 110 and is connected to the analog input port of the main controller 102 via a shielded cable to continuously provide water temperature feedback signal T_fb. The power sensor 105 has its sampling end connected in series in the power supply circuit of the plasma reactor 110, and its signal output end connected to the digital input port of the main controller 102 via the I²C bus to continuously provide the discharge power feedback signal P_fb. The human-machine interface 108 is provided with at least an asynchronous serial communication port for sending temperature setpoint T_set, power setpoint P_set and minimum power protection value P_min to the main controller 102, and receiving the measured temperature T_fb and measured power P_fb returned by the main controller in real time. The main controller 102 integrates a temperature fuzzy PID controller 103, a power fuzzy PID controller 104, and an intelligent coordinator 106, and interconnects these components in parallel via an internal data bus. The input terminal of the temperature fuzzy PID controller 103 is connected to the output terminal of the temperature sensor 101, and the output terminal of the temperature fuzzy PID controller 103 is connected to the intelligent coordinator 106 via an internal bus to output the temperature-side suggested power U_t. The input terminal of the power fuzzy PID controller 104 is connected to the output terminal of the power sensor 105, and the output terminal of the power fuzzy PID controller 104 is connected to the intelligent coordinator 106 via an internal bus to output the power-side suggested power U_p. The first output terminal of the intelligent coordinator 106 is connected to the control terminal of the power actuator 109 via a PWM pin, and its second output terminal is connected to the control terminal of the temperature actuator 107 via a MOSFET or PWM pin, for outputting the final power command P_final and cooling control signal according to the following state machine logic: When T_fb≤T_set, the normal power output mode is adopted, the output P_final=U_t is displayed and the auxiliary cooling is turned off; When T_fb > T_set and P_fb > P_min, the normal power output mode is adopted, the output P_final = U_t is displayed and the auxiliary cooling is turned off; When T_fb > T_set and P_fb ≤ P_min, the forced cooling mode is adopted, P_final = P_min is output and auxiliary cooling is started; The power actuator 109 has its power input terminal connected to an external DC bus and its high voltage output terminal electrically connected to the discharge electrode of the plasma reactor 110, and is used to continuously adjust the discharge power according to the final power command P_final. The temperature actuator 107, whose cooling end or air-cooled outlet is thermally coupled to the water body of the plasma reactor 110, is used to implement forced heat dissipation according to the cooling control signal. The plasma reactor 110 has an inlet connected to an external water source and an outlet outputting highly active plasma-activated water. Its discharge electrode receives high-voltage electrical energy from the power actuator 109, thereby generating active species in the water. In this embodiment, the plasma reactor is the core reaction unit for generating active species. The plasma reactor receives regulated plasma emission power. Preferably, the plasma reactor employs a dielectric barrier discharge structure, which uses a high-voltage electric field to ionize gas, generating plasma rich in active particles, and allowing for a thorough gas-liquid phase mass transfer reaction with the water flow.

[0032] The entire system workflow is as follows: Temperature sensor 101 and power sensor 105 collect real-time data on actual temperature and power, respectively, and send the data to main controller 102. Temperature fuzzy PID controller 103 and power fuzzy PID controller 104 within main controller 102 operate in parallel. They compare the received feedback signals with internal setpoints and perform complex fuzzy inference calculations to generate a suggested power signal. These two suggested power signals are sent to intelligent coordinator 106. Intelligent coordinator 106 comprehensively considers these two suggestions, as well as the system's real-time temperature and power status, and uses preset expert rules (e.g., prioritizing power not falling below the minimum value for active substance generation when the temperature is too high) to make a final decision and generate two independent control commands: temperature control for the cooling device and power control for the plasma reactor. Temperature actuator 107 starts, stops, or adjusts the cooling intensity according to the temperature control command. Power actuator 109 precisely adjusts the power output to plasma reactor 110 according to the power control command. Plasma reactor 110 operates under optimized power and temperature conditions, stably producing highly active plasma-activated water. Meanwhile, the operating status of the entire system is displayed in real time through the human-machine interface 108, and users can also use it to set parameters and intervene in the system operation.

[0033] In a preferred embodiment of the present invention, the temperature sensor 101 includes a high-precision platinum resistance temperature sensor, used to convert the non-electrical quantity temperature of the reaction system into a standard electrical signal, and to provide accurate and continuous feedback information for the temperature fuzzy PID controller, forming the starting point of the temperature control closed loop. In this embodiment, a PT100 platinum resistance temperature sensor is preferably used.

[0034] In a preferred embodiment of the present invention, the power sensor 105 includes an integrated AC power sensor for high-precision, isolated measurement of plasma discharge power. It provides a direct feedback signal reflecting the energy input magnitude to the power fuzzy PID controller 104 and the intelligent coordinator 106, serving as a crucial basis for power control closed-loop and system collaborative decision-making. In this embodiment, the CHY195, based on the Hall effect principle, is preferably used.

[0035] In a specific implementation, as a preferred embodiment of the present invention, the main controller 102 is the core of the entire system's computation and control, implemented by an STM32F407 series chip from STMicroelectronics. The main controller 102 stores control algorithms in its internal memory, enabling the microcontroller to implement a parallel dual-fuzzy PID control algorithm and intelligent coordinator decision logic. Under the algorithm control, the microcontroller executes the calculation processes of the temperature fuzzy PID controller 103 and the power fuzzy PID controller 104 in parallel, and then runs the state machine decision logic of the intelligent coordinator 106, ultimately generating control instructions for the power actuator 109 and the temperature actuator 107.

[0036] In a specific implementation, as a preferred embodiment of the present invention, when the power sensor 105 is an analog output type, the main controller 102 uses an ADC to acquire the power; when the power sensor 105 is a digital type, the main controller 102 uses an SPI or I2C interface to read the power and obtain the real-time power value P_fb.

[0037] In a specific implementation, as a preferred embodiment of the present invention, the main controller 102 is connected to the drive circuit in the power actuator 109 to precisely control the on / off state of the power switching device, thereby adjusting the plasma discharge power; the main controller 102 is connected to the drive circuit of the temperature actuator 107 through a general-purpose input / output port or another PWM channel to control the start / stop and speed adjustment of the cooling fan or the thermoelectric cooler.

[0038] In a specific implementation, as a preferred embodiment of the present invention, the temperature fuzzy PID controller 103 is used to adaptively adjust the control strategy according to the temperature deviation and its trend, and output a preliminary power demand signal. The temperature fuzzy PID controller 103 internally includes fuzzy subsets, fuzzy rules, fuzzy inference and defuzzification interfaces. The input of the temperature fuzzy PID controller 103 is the temperature error T_e and its rate of change T_ec, where T_e is calculated from the preset temperature setpoint T_set and the real-time temperature T_fb. The output is a suggested power value U_t for temperature control.

[0039] In a specific implementation, as a preferred embodiment of the present invention, the power fuzzy PID controller 104 and the temperature fuzzy PID controller 103 operate in parallel to adaptively adjust the control strategy based on the power deviation and its trend, and output a preliminary power demand signal. The power fuzzy PID controller 104 internally includes fuzzy subsets, fuzzy rules, fuzzy inference, and defuzzification interfaces. The input of the power fuzzy PID controller 104 is the power error P_e and its rate of change P_ec, where P_e is calculated from the preset power setpoint P_set and the real-time power value P_fb. The output is a power suggestion U_p.

[0040] In a specific implementation, as a preferred embodiment of the present invention, the temperature actuator 107 is a physical actuator for auxiliary temperature control, specifically manifested as the auxiliary cooling system; the control terminal of the temperature actuator 107 is connected to the MOSFET or PWM output pin of the main controller 102, and receives start / stop and speed adjustment commands from the intelligent coordinator 106; the active terminal of the temperature actuator 107, such as the air outlet of a fan or the cold end of a semiconductor cooling chip, points to or contacts the water body of plasma-activated water. When the system enters the forced cooling mode, it starts and performs forced heat dissipation with adjustable intensity according to the command, thereby effectively suppressing the rise in temperature of the reaction system when the power is locked at P_min.

[0041] In a preferred embodiment of the present invention, the power actuator 109 is an actuator for adjusting the plasma discharge power. Its control terminal is connected to the output terminal of the main controller 102 to receive PWM control signals and, based on the received PWM control signals, realize continuous and precise control of the discharge power of the plasma reactor 110. In this embodiment, the power actuator 109 includes power switching devices such as MOSFETs or IGBTs and their driving circuits.

[0042] like Figure 2 The diagram shown is a schematic of the dual fuzzy PID controller of the present invention, and its specific principle is as follows: The temperature setpoint T_set serves as the main control objective of the system, defining the optimal operating temperature for plasma-activated water. Input comes from the setting command of the main controller 102. The system compares this setpoint with the actual temperature value collected by the temperature sensor 101, calculating the temperature error T_e. This error is the basic input to the temperature fuzzy PID controller 103, and parameter transmission is completed through digital signal transmission.

[0043] The dynamic trend of temperature error is analyzed by receiving real-time measurement data from temperature sensors. The rate of change of temperature error is calculated using a digital differential algorithm, and a differential signal reflecting the rate of temperature change is output. This process provides key dynamic response parameters for the fuzzy control system, enhancing the system's predictive control capability.

[0044] The temperature fuzzy subset, as the core of the fuzzification process, converts precise temperature errors and rates of change into fuzzy linguistic variables. Based on a preset membership function, fuzzy sets of "negative large (NB), negative small (NS), zero (ZE), positive small (PS), and positive large (PB)" are established. The mapping from precise quantities to fuzzy quantities is achieved through a fuzzification interface, laying the foundation for subsequent fuzzy inference. Typically, this is converted into a fuzzy set using a fuzzy quantization function. In this process, the membership degree is obtained through membership functions and quantization of the input variables.

[0045] Temperature fuzzy inference is the core decision-making unit of temperature fuzzy control, receiving input variables from a fuzzy subset. It employs fuzzy logic inference methods, combined with an expert knowledge base, to intelligently analyze the current system state. It outputs fuzzy decision results for PID parameter adjustment, achieving rule-based intelligent control.

[0046] Temperature fuzzy rules are a rule library storing expert experience and knowledge in the field of temperature control, in IF-THEN format. It receives query requests from the fuzzy inference engine and matches corresponding control rules based on the input fuzzy variables. It outputs strategy suggestions for parameter adjustment, ensuring the control system can simulate the decision-making process of human experts.

[0047] Temperature defuzzification converts fuzzy inference results into precise control parameters. A centroid-based defuzzification algorithm is used to process the fuzzy quantities in the fuzzy inference output. Precise PID parameter correction values ​​are output, providing directly usable parameter adjustment values ​​for subsequent temperature PID controllers.

[0048] Temperature correction involves performing specific parameter adjustment calculations and receiving the defuzzified output parameter adjustment amount. Based on preset PID parameter baseline values, it generates real-time optimized parameters through arithmetic operations. The output is then adaptively adjusted PID parameters to ensure the controller can adapt to changes in the system's dynamic characteristics.

[0049] The temperature fuzzy PID controller 103 serves as the core of temperature control execution, receiving corrected PID parameters and temperature error signals. It employs a standard PID algorithm to calculate the control output and adjusts the system's operating state in real time. It outputs a suggested power for temperature control, providing decision-making support for the intelligent coordinator.

[0050] The power setpoint P_set serves as the baseline target and minimum output standard for defining the power control loop, receiving power setting commands from the main controller. The power setpoint is dynamically adjusted based on the system operating status and active ingredient generation requirements. It acts as the target reference for output power control, ensuring coordinated operation between power control and temperature control. The system compares this setpoint with the actual power value collected by the power sensor to calculate the power error P_e. This error is the basic input to the power fuzzy PID controller 104, and data is transmitted via a digital signal interface.

[0051] Power error differentiation monitors the dynamic changes in power error and calculates its trend in real time. By performing differentiation operations, it captures the dynamic response characteristics of the power system, providing necessary dynamic parameters for fuzzy power control. The output power error rate of change enhances the rapid response capability of power control.

[0052] The power fuzzy subset is specifically designed to handle power-related fuzzy transformations, establishing a set of fuzzy linguistic variables for power control. It maps precise power errors and their rates of change to corresponding fuzzy sets, employing a fuzzification strategy similar to that used in the temperature loop. It outputs a fuzzy descriptor of power, ensuring the smooth implementation of fuzzy power control.

[0053] Power fuzzy inference independently executes the fuzzy inference process for power control, focusing on the characteristic analysis of the power system. Based on professional knowledge and empirical rules of power control, it performs intelligent reasoning and decision-making. It outputs fuzzy adjustment suggestions for power PID parameters, achieving intelligent optimization of the power system.

[0054] The power fuzzy rule is a unique expert rule base for power control, optimized for the operating characteristics of the power system. It receives input of power fuzzy variables and matches the most suitable control rule for the current operating conditions. It outputs fuzzy instructions for adjusting power parameters, ensuring the accuracy and stability of power control.

[0055] Power defuzzification is a specialized function that handles the defuzzification calculations of power control loops, converting fuzzy inference results into precise numerical values. An optimized defuzzification algorithm is employed to ensure the accuracy and smoothness of power parameter adjustments. It outputs precise power PID parameter corrections, providing directly usable parameters for the power controller.

[0056] Power correction involves performing actual adjustments to the power PID parameters and updating the controller parameters based on the adjustments made in the defuzzified output. This optimizes the power controller's performance in real time, adapting to control requirements under different operating conditions. The optimized power PID parameters are output to ensure the adaptability and robustness of power control.

[0057] The power fuzzy PID controller 104, as the final execution unit for power control, receives the corrected PID parameters and power error signal. It calculates the power adjustment amount using a precise PID algorithm, controlling the plasma power supply output in real time. It outputs a power control signal, providing accurate control commands to the actuator.

[0058] The power sensor 105 monitors the actual power consumption of the plasma system in real time, acquiring power data through a precision measurement circuit. Isolation detection technology ensures system safety and provides accurate power feedback signals. It outputs real-time power measurements, providing reliable feedback information to the power control loop.

[0059] Temperature sensor 101 directly detects the actual temperature of the plasma-activated water, employing a high-precision temperature sensing element. It reflects the system temperature status in real time and outputs a temperature measurement signal, forming a key feedback loop in the temperature control closed loop.

[0060] The intelligent coordinator 106 serves as the decision-making center of the entire control system, coordinating the operation of the temperature and power dual loops. It comprehensively analyzes the output suggestions of both loops and the real-time system status, making intelligent decisions based on a preset coordination strategy. Finally, it outputs the execution command to achieve optimal temperature and power matching control.

[0061] The system generates final execution commands, including PWM signals for power regulation and cooler control signals. Based on the decisions of the intelligent coordinator, it outputs corresponding control commands to drive the actuators. This ensures the system operates under optimal conditions, maximizing the generation of active substances in plasma-activated water.

[0062] This system employs an improved parallel dual-fuzzy PID control architecture to achieve intelligent coordinated control of temperature and power. The system processes temperature and power parameters separately through independent fuzzy control loops, and then achieves overall optimization through an intelligent coordinator. This design effectively solves the control challenges of multivariable coupling, nonlinearity, and time-varying characteristics in the plasma-activated water preparation process, ensuring that the system maintains optimal operating conditions under various operating conditions, ultimately achieving the comprehensive control objective of maximizing active ingredient concentration and minimizing energy consumption.

[0063] like Figure 3 The diagram shows a flowchart of the system of this invention. After the system starts, during the initial system setting phase, key parameters such as the minimum power protection value P_min and the temperature setting T_set required to ensure the generation of active substances are input. Subsequently, the system enters a closed loop of real-time monitoring and control. First, the actual temperature T_fb of the plasma-activated water and the actual power P_fb of the plasma discharge are collected in real time. Based on these data, the system executes a dual fuzzy PID control algorithm in parallel. The temperature fuzzy PID controller 103 calculates the suggested power U_t for stabilizing the temperature based on the temperature error and its rate of change. At the same time, the power fuzzy PID controller 104 independently calculates another suggested power U_p based on the power error and its rate of change.

[0064] Afterward, the process enters the core decision-making stage: the intelligent coordinator 106 comprehensively analyzes the current temperature status and power level. If the actual temperature does not exceed the set value (T_fb<= T_set), the system adopts the "normal power output" mode, directly adopts the temperature controller's suggestion, i.e., P_final = U_t, and shuts down the cooling system. If the actual temperature exceeds the limit (T_fb>T_set), the intelligent coordinator 106 further checks the power level: if the current power is still higher than the minimum protection value (P_fb>P_min), it enters the "priority power reduction" mode, at which time it still outputs P_final=U_t (because the temperature fuzzy PID controller 103 will automatically reduce its suggested power for cooling), attempting to control the temperature in the most energy-efficient way; if the power has dropped to the critical point (P_fb<=P_min), it immediately switches to the "forced cooling mode," at which point the intelligent coordinator 106 locks the final power command to P_min to absolutely guarantee the minimum energy required for active material generation, and simultaneously starts the auxiliary cooling system to perform forced heat dissipation from the outside.

[0065] Finally, the decision signal P_final output by the intelligent coordinator 106 is converted into a precise PWM control signal, which is then used by the power actuator 109 and the temperature actuator 107 to work together on the plasma reactor 110, thereby maintaining the reaction system in the optimal state under complex operating conditions and stably producing highly active plasma-activated water.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plasma activated water preparation system based on fuzzy PID adaptive temperature and power matching co-control, characterized in that, The application relates to a temperature and power control system for plasma reactor, which comprises a main controller (102), a temperature sensor (101), a power sensor (105), a temperature actuator (107), a man-machine interface (108), a power actuator (109) and a plasma reactor (110), wherein: The temperature sensor (101) is immersed in the water body of the plasma reactor (110) and is connected to the analog input port of the main controller (102) through a shielded cable, so as to continuously provide a water temperature feedback signal T_fb; The power sensor (105) is connected in series in the power supply loop of the plasma reactor (110) and is connected to the digital input port of the main controller (102) through an I2C bus, so as to continuously provide a discharge power feedback signal P_fb; The man-machine interface (108) is provided with at least an asynchronous serial communication port, which is used for issuing a temperature setting value T_set, a power setting value P_set and a minimum power protection value P_min to the main controller (102) and receiving the measured temperature T_fb and the measured power P_fb returned by the main controller in real time; The main controller (102) is integrated with a temperature fuzzy PID controller (103), a power fuzzy PID controller (104) and an intelligent coordinator (106) and is connected in parallel with the temperature fuzzy PID controller (103), the power fuzzy PID controller (104) and the intelligent coordinator (106) through an internal data bus, wherein: The input end of the temperature fuzzy PID controller (103) is connected with the output end of the temperature sensor (101), the output end of the temperature fuzzy PID controller (103) is connected with the intelligent coordinator (106) through the internal bus, and the temperature fuzzy PID controller (103) is used for outputting a temperature-side recommended power U_t; The input end of the power fuzzy PID controller (104) is connected with the output end of the power sensor (105), the output end of the power fuzzy PID controller (104) is connected with the intelligent coordinator (106) through the internal bus, and the power fuzzy PID controller (104) is used for outputting a power-side recommended power U_p; The first output end of the intelligent coordinator (106) is connected with the control end of the power actuator (109) through a PWM pin, the second output end of the intelligent coordinator (106) is connected with the control end of the temperature actuator (107) through a MOSFET or a PWM pin, and the intelligent coordinator (106) is used for outputting a final power instruction P_final and a cooling control signal according to the following state machine logic: When T_fb<=T_set, a normal power output mode is adopted, P_final=U_t is outputted, and the auxiliary cooling is turned off; When T_fb>T_set and P_fb>P_min, the normal power output mode is adopted, P_final=U_t is outputted, and the auxiliary cooling is turned off; When T_fb>T_set and P_fb<=P_min, a forced cooling mode is adopted, P_final=P_min is outputted, and the auxiliary cooling is started. ​ The power executor (109) has a power input end connected with an external DC bus and a high-voltage output end electrically connected with a discharge electrode of the plasma reactor (110) for continuously adjusting the discharge power according to a final power instruction P_final. The temperature executor (107) has a refrigeration end or a wind cooling outlet thermally coupled with a water body of the plasma reactor (110) for implementing forced heat dissipation according to the cooling control signal. The plasma reactor (110) has a water inlet connected with an external water source to be treated and a water outlet outputting high-activity plasma activated water, and the discharge electrode receives high-voltage electric energy from the power executor (109) to generate active species in the water.

2. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching coordinated control according to claim 1, characterized in that, The temperature sensor (101) includes a high-precision platinum resistance temperature sensor for converting a non-electric quantity temperature of the reaction system into a standard electric signal and providing accurate and continuous feedback information for the temperature fuzzy PID controller, thereby constituting a starting point of a temperature control closed loop.

3. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching coordinated control according to claim 1, characterized in that, The power sensor (105) includes an integrated AC power sensor for realizing high-precision and isolated measurement of the plasma discharge power and providing a direct feedback signal reflecting the size of energy input for the power fuzzy PID controller (104) and the intelligent coordinator (106), thereby being an important basis for power control closed loop and system collaborative decision.

4. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching coordinated control according to claim 1, characterized in that, When the power sensor (105) is an analog output type, the main controller (102) uses an ADC to collect; when the power sensor (105) is a digital type, the main controller (102) uses an SPI or I2C interface to read, thereby obtaining a real-time power value P_fb.

5. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching coordinated control according to claim 1, characterized in that, The main controller (102) is connected with a driving circuit in the power executor (109) for accurately controlling on-off of a power switching device and thereby adjusting the plasma discharge power; the main controller (102) is connected with a driving circuit of the temperature executor (107) through a general input-output port or another PWM channel for controlling start-stop and speed regulation of a cooling fan or a semiconductor refrigeration sheet.

6. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching co-control according to claim 1, characterized in that, The main controller (102) has a control algorithm stored in an internal memory, so that the microcontroller realizes parallel double-fuzzy PID control algorithm and intelligent coordinator decision logic; under the algorithm control, the microcontroller executes calculation processes of the temperature fuzzy PID controller (103) and the power fuzzy PID controller (104) in parallel, and then runs state machine decision logic of the intelligent coordinator (106), thereby finally generating control instructions for the power executor (109) and the temperature executor (107).

7. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching co-control according to claim 1, characterized in that, The temperature fuzzy PID controller (103) is used to adaptively adjust the control strategy according to the temperature deviation and its trend, and outputs a preliminary power demand signal; the temperature fuzzy PID controller (103) internally contains fuzzy subsets, fuzzy rules, fuzzy reasoning and defuzzification interface, the input quantity of the temperature fuzzy PID controller (103) is temperature error T_e and its change rate T_ec, wherein T_e is calculated from the preset temperature set value T_set and the real-time temperature T_fb, and the output quantity is a recommended power value U_t for temperature control.

8. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching coordinated control according to claim 1, characterized in that, The power fuzzy PID controller (104) runs in parallel with the temperature fuzzy PID controller (103), and is used to adaptively adjust the control strategy according to the power deviation and its trend, and outputs a preliminary power demand signal; the power fuzzy PID controller (104) internally contains fuzzy subsets, fuzzy rules, fuzzy reasoning and defuzzification interface, the input quantity of the power fuzzy PID controller (104) is power error P_e and its change rate P_ec, wherein P_e is calculated from the preset power set value P_set and the real-time power value P_fb, and the output quantity is a recommended power U_p for output. 9.The plasma activated water system based on fuzzy PID adaptive temperature and power matching coordinated control according to claim 1, wherein, The temperature actuator (107) is a physical execution device for assisting temperature control, the control end of the temperature actuator (107) is connected with the MOSFET or PWM output pin of the main controller (102), receives start-stop and speed regulation instructions from the intelligent coordinator (106); the action end of the temperature actuator (107) such as the outlet of the fan or the cold end of the semiconductor refrigeration piece points to or contacts the water body of the plasma activated water, when the system enters the forced cooling mode, starts and performs intensity-adjustable forced heat dissipation according to the instructions, so as to suppress the rise of the reaction system temperature when the power is locked as P_min.

10. The plasma activated water generating system based on fuzzy PID adaptive temperature and power matching co-control according to claim 1, characterized in that, The power actuator (109) is an execution device for adjusting the power of plasma discharge, the control end of which is connected with the output end of the main controller (102), for receiving the PWM control signal, and realizing continuous and accurate control of the discharge power of the plasma reaction machine (110) according to the received PWM control signal.

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