Multi-parameter liquid injection control method and system for hydrogen peroxide spatial sterilization system

Abstract

The application discloses a multi-parameter liquid injection control method and system of a hydrogen peroxide space sterilization system, and belongs to the technical field of space sterilization control. The method extracts dynamic response characteristics at the initial stage of liquid injection, accurately calculates the actual effective volume of the cavity and the comprehensive loss coefficient, and calculates the amount of liquid to be supplemented accordingly. During the liquid injection process, the vacuum suction and carrier gas inlet rate are dynamically adjusted based on the liquid injection rate and the air pressure change rate to construct a matching steady-state air flow circulation. At the same time, based on the comprehensive loss evaluation and real-time concentration, a compound compensation strategy combining feedforward and feedback is generated to close-loop fine-tune and maintain the target sterilization concentration. In addition, the system triggers the out-of-limit protection according to the multi-dimensional condensation constraint parameters in real time. The application overcomes the defects of traditional single-variable control that is prone to overshoot and condensation, realizes precise dose control and air flow state coordination under complex working conditions, and perfectly avoids the condensation corrosion phenomenon while ensuring efficient sterilization.

Description

Technical Field

[0001] This invention belongs to the field of space sterilization control technology, specifically relating to a multi-parameter liquid injection control method and system for a hydrogen peroxide space sterilization system. Background Technology

[0002] Hydrogen peroxide space sterilization technology, as a highly efficient and broad-spectrum cold sterilization method, is widely used in the decontamination of enclosed or semi-enclosed spaces such as biosafety laboratories, clean rooms, and sterile isolators. Its basic principle is to vaporize liquid hydrogen peroxide and introduce it along with a carrier gas into the chamber to be sterilized, thereby achieving and maintaining a specific target concentration within the space, thus thoroughly killing microorganisms in the environment. During the actual injection and sterilization process, the gas within the sterilization space is a mixture of hydrogen peroxide vapor and water vapor, and the physical states within the chamber, such as gas pressure, temperature, humidity, and hydrogen peroxide concentration, undergo complex nonlinear changes with the continuous introduction and dynamic circulation of the gaseous substance.

[0003] However, existing hydrogen peroxide injection control methods have significant limitations when dealing with complex and variable real-world operating conditions. Currently, industrial applications often employ time-based or fixed-formula program control methods. These open-loop controls do not consider the impact of real-time variables such as load occupancy, natural losses, and environmental differences within the sterilization space. This leads to frequent issues like insufficient effective concentration causing sterilization failure in different batches or application scenarios, or localized oversaturation leading to severe condensation, resulting in high-concentration residues and corrosion of equipment materials. On the other hand, some closed-loop control systems based on single-concentration feedback, while incorporating real-time monitoring, suffer from inherent physical lag in the injection, vaporization, and diffusion processes of the liquid sterilizing agent. Simple feedback based on a single variable easily causes system overshoot and operational oscillations. More importantly, these methods often pursue concentration indicators in isolation, severing the strong coupling between the sterilizing agent injection process and the chamber's airflow circulation, pressure changes, and thermodynamic state. This makes it difficult for existing technologies to effectively balance ensuring sterilization consistency across different areas of the space, preventing localized condensation, and improving system operational stability when facing fluctuating operating conditions. Summary of the Invention

[0004] This invention provides a multi-parameter liquid injection control method and system for a hydrogen peroxide space sterilization system, which solves the problem that existing control methods cannot achieve a dynamic balance between preventing condensation, avoiding excessive concentration, and ensuring sterilization effect because they do not fully utilize the physical parameters of the mixed steam.

[0005] To achieve the above objectives, one embodiment of the present invention provides a multi-parameter injection control method for a hydrogen peroxide space sterilization system, comprising the following steps: Step S1: After evacuating the sterilization chamber to a preset initial vacuum level, hydrogen peroxide is simultaneously injected into the sterilization chamber and a carrier gas is introduced, while real-time acquisition of sterilization process parameters during the introduction process; dynamic response characteristics are extracted based on the sterilization process parameters, and spatial characteristic parameters and comprehensive loss coefficient of the sterilization chamber are calculated; Step S2: Based on the spatial characteristic parameters, comprehensive loss coefficient, and preset target sterilization concentration, the amount to be replenished is calculated using a loss compensation dose calculation strategy. Liquid volume; Step S3: Inject the amount of hydrogen peroxide to be replenished into the sterilization chamber; During the injection process, dynamically adjust the vacuum suction rate and carrier gas introduction rate according to the current hydrogen peroxide injection rate and the real-time gas pressure change rate in the sterilization chamber, so as to form a steady-state airflow circulation in the sterilization chamber that matches the current injection process; Step S4: Generate a hydrogen peroxide injection compensation strategy according to the sterilization process parameters and comprehensive loss coefficient obtained in real time in the sterilization chamber, and dynamically adjust the hydrogen peroxide injection rate according to the compensation strategy, so that the hydrogen peroxide concentration in the sterilization chamber is stably maintained within the preset target sterilization concentration level.

[0006] Optionally, the sterilization process parameters in step S1 include the real-time gas pressure, real-time chamber temperature, hydrogen peroxide injection rate, and carrier gas introduction rate within the sterilization chamber; the extraction of dynamic response characteristics based on the sterilization process parameters specifically includes: continuously acquiring the sterilization process parameters during hydrogen peroxide injection and carrier gas introduction; extracting the real-time gas pressure change rate and the temperature fluctuation gradient during the pressure rise process within the sterilization chamber based on the continuously acquired sterilization process parameters; and using the real-time gas pressure change rate and the temperature fluctuation gradient as the dynamic response characteristics.

[0007] Optionally, the calculation of the spatial characteristic parameters and comprehensive loss coefficient of the sterilization chamber specifically includes: determining the mass expansion rate of the gaseous substance currently input into the sterilization chamber based on the injection rate of hydrogen peroxide, the inlet rate of the carrier gas, and the real-time chamber temperature; extracting the initial lossless maximum rate from the real-time pressure change rate; calculating the spatial characteristic parameters characterizing the effective physical volume of the sterilization chamber based on the proportional relationship between the gaseous substance mass expansion rate and the initial lossless maximum rate; calculating the initial pressure change rate based on the gaseous substance mass expansion rate and the spatial characteristic parameters; calculating the pressure rise attenuation deviation based on the initial pressure change rate and the real-time pressure change rate; and calculating the comprehensive loss coefficient based on the pressure rise attenuation deviation and the temperature fluctuation gradient to characterize the adsorption, leakage, and natural decomposition effects on the chamber wall.

[0008] Optionally, the loss compensation dosage calculation strategy includes: determining the reference gas mass required by the sterilization chamber under the target sterilization state based on the spatial characteristic parameters and the preset target sterilization concentration; determining the compensation gas mass caused by adsorption, leakage and natural decomposition on the chamber wall during sterilization based on the comprehensive loss coefficient and the preset sterilization holding time; and summing the reference gas mass and the compensation gas mass to obtain the volume of liquid to be replenished.

[0009] Optionally, the process of dynamically adjusting the vacuum suction rate and the carrier gas inlet rate in step S3 specifically includes: Step S31: Calculating the theoretical pressure change rate corresponding to hydrogen peroxide vaporization based on the current hydrogen peroxide injection rate, and matching and determining the vacuum suction reference rate and the carrier gas inlet reference rate; Step S32: Real-time acquisition of the real-time gas pressure in the sterilization chamber, and calculating the real-time pressure change rate; Step S33: Synchronously and in conjunction with the vacuum suction reference rate and the carrier gas inlet reference rate, based on the deviation between the real-time gas pressure and the preset sub-normal pressure target gas pressure range, and the real-time pressure change rate.

[0010] Optionally, step S33 specifically includes: calculating the pressure deviation between the real-time air pressure and the preset sub-normal pressure target air pressure range; combining the pressure deviation with the real-time air pressure change rate, generating a vacuum suction rate correction value and a carrier gas inlet rate correction value respectively through a closed-loop control algorithm; superimposing the vacuum suction rate correction value onto the vacuum suction reference rate, and superimposing the carrier gas inlet rate correction value onto the carrier gas inlet reference rate, performing synchronous linkage correction on the two.

[0011] Optionally, the execution logic of the closed-loop control algorithm includes: generating a proportional control response to suppress instantaneous errors based on the current amplitude of the pressure deviation value; generating an integral control response to eliminate steady-state errors based on the cumulative state of the pressure deviation value over time; generating a derivative control response to suppress pressure fluctuations based on the real-time pressure change rate; fusing the proportional, integral, and derivative control responses to generate a comprehensive control quantity; and calculating the vacuum suction rate correction value and the carrier gas injection rate correction value based on the comprehensive control quantity according to preset weight allocation coefficients.

[0012] Optionally, during the hydrogen peroxide injection process, an anti-condensation safety constraint strategy is also implemented, specifically including: real-time acquisition of the lowest surface temperature of the sterilization chamber and the relative saturation of the mixed vapor as condensation constraint parameters; when the relative saturation of the mixed vapor reaches a preset upper limit threshold, or the difference between the dew point temperature of the mixed vapor and the lowest surface temperature of the chamber reaches a preset lower limit threshold, an over-limit protection mechanism is triggered to dynamically reduce the current hydrogen peroxide injection rate and simultaneously increase the carrier gas inlet rate until the condensation constraint parameters fall back to the safe range.

[0013] Optionally, the process of generating the hydrogen peroxide injection compensation strategy in step S4 specifically includes: calculating the hydrogen peroxide concentration decay per unit time under the current operating conditions based on the comprehensive loss coefficient, and converting it into a feedforward compensation injection amount; collecting the real-time concentration of hydrogen peroxide in the sterilization chamber, calculating the concentration deviation between the real-time concentration and the preset target sterilization concentration, and calculating the feedback adjustment injection amount based on the concentration deviation; and superimposing the feedforward compensation injection amount and the feedback adjustment injection amount to generate the hydrogen peroxide injection compensation strategy, wherein the compensation strategy is used to output the hydrogen peroxide fine-tuning injection rate for the corresponding time period.

[0014] On the other hand, a multi-parameter injection control system for a hydrogen peroxide space sterilization system is also provided to implement the above-mentioned multi-parameter injection control method. This system includes a main control unit and, in communication with the main control unit, an evaporation injection unit, a vacuum suction unit, a carrier gas supply unit, a parameter monitoring unit, and a catalytic decomposition and residue removal unit. The parameter monitoring unit is located at a preset position within the sterilization chamber to acquire sterilization process parameters in real time. The main control unit is configured to: after the vacuum suction unit evacuates the sterilization chamber to a preset initial vacuum level, control the evaporation injection unit and the carrier gas supply unit to synchronously inject hydrogen peroxide into the sterilization chamber. Hydrogen peroxide is oxidized and carrier gas is introduced, and the spatial characteristic parameters and comprehensive loss coefficient of the sterilization chamber are calculated. The amount of liquid to be replenished is determined based on the loss compensation dosage calculation strategy. During the liquid injection process, the vacuum suction rate and the carrier gas introduction rate are coordinated to construct a steady-state airflow circulation. An injection compensation strategy is generated through feedforward compensation combined with feedback correction to maintain concentration stability. The evaporation liquid injection unit, vacuum suction unit and carrier gas supply unit are used to receive instructions from the main control unit and execute the liquid injection, suction and carrier gas introduction actions accordingly. The catalytic decomposition and residue removal unit is used to decompose the residual hydrogen peroxide in the sterilization chamber after sterilization.

[0015] This invention provides a multi-parameter injection control method and system for a hydrogen peroxide space sterilization system. By extracting dynamic response characteristics in the initial stage of injection to accurately calculate the actual effective volume and comprehensive loss coefficient of the cavity, it achieves adaptive identification and precise dosage control under complex loads and variable operating conditions, fundamentally avoiding the risk of insufficient or excessive injection caused by traditional empirical estimation. Simultaneously, during the injection process, the vacuum suction and carrier gas introduction are dynamically linked and coordinated according to the real-time injection rate and gas pressure change rate. While maintaining a safe sub-atmospheric pressure environment, a steady-state airflow circulation matching the injection volume is constructed in the cavity, which greatly promotes the uniform and rapid diffusion of sterilizing gas. On this basis, by integrating feedforward compensation based on loss assessment and feedback correction of real-time concentration, the target sterilization concentration can be maintained with high precision and long-term effectiveness. Combined with a condensation over-limit protection mechanism based on the physical properties of mixed steam, the occurrence of condensation is curbed from the source, perfectly achieving a dynamic balance between ensuring efficient microbial killing, preventing cavity material corrosion, and suppressing fluctuations in operating conditions. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this 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 this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic diagram of the multi-parameter injection control system provided in an embodiment of the present invention; Figure 2 This is a flowchart of the multi-parameter injection control method provided in the embodiments of the present invention; Figure 3 This is a schematic diagram of the physical structure for the coordinated control of the sterilization chamber in an embodiment of the present invention; Figure 4 This is a schematic diagram of the anti-condensation safety constraint parameters provided in an embodiment of the present invention; Figure 5 This is a schematic diagram illustrating the principle of calculating spatial characteristic parameters and comprehensive loss coefficients provided in this embodiment of the invention. Detailed Implementation

[0017] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0018] It should be noted that the acquisition, transmission, storage, use, and processing of data in the technical solution of this application all comply with the relevant provisions of national laws and regulations. In the embodiments of this application, certain existing industry solutions such as software, components, and models may be mentioned. These should be considered exemplary, intended only to illustrate the feasibility of implementing the technical solution of this application, and do not imply that the applicant has already used or necessarily used such solutions.

[0019] The following is combined Figures 1-5 This invention is described in detail.

[0020] like Figure 1 and Figure 3 As shown in the figure, this invention provides a multi-parameter liquid injection control method and system for a hydrogen peroxide space sterilization system. The system mainly includes a main control unit, an evaporation liquid injection unit, a vacuum suction unit, a carrier gas supply unit, a parameter monitoring unit, and a catalytic decomposition residue removal unit for rapid residue removal and decontamination after sterilization. Each functional unit is electrically connected to the main control unit via an industrial communication bus, receives unified scheduling commands from the main control unit, and provides real-time feedback of local operating status and collected data to the main control unit.

[0021] The main control unit is the core of the system's computation and scheduling. It integrates a parameter identification module, a dosage calculation module, a closed-loop control module, and a safety constraint module. It can perform functions such as time-series data processing, operating condition parameter identification, injection dosage calculation, multi-unit collaborative control, and threshold over-limit protection. The main control unit supports both single-cavity centralized control and multi-area distributed collaborative control modes. The number of evaporators and monitoring points can be flexibly configured according to the size and structure of the sterilization space, adapting to closed cavities of different volumes. All control logic of the main control unit uses real-time data collected by the parameter monitoring unit as input and adjustment commands from each execution unit as output, forming a complete closed-loop control chain.

[0022] The evaporation and injection unit is used to meter and controllably vaporize liquid hydrogen peroxide. At least one unit should be installed, and multiple units can be deployed in a distributed manner in large spaces or multi-area scenarios. Each evaporation and injection unit consists of a liquid storage module, a precision metering injection module, and a vaporization module. The precision metering injection module uses a plunger-type metering pump structure, which can achieve precise control of the injection rate at the micro-liter level, and the output range covers the full operating conditions from the low rate of trial injection to the maximum rate of main injection. The vaporization module adopts a multi-area zone heating structure with adaptive adjustment function for the evaporation surface temperature. It can dynamically match the output power of each heating area according to the current injection rate to ensure that the liquid hydrogen peroxide is completely vaporized on the evaporation surface and prevent droplets from being entrained into the sterilization chamber. Multiple distributed evaporation and injection units can independently receive injection commands from the main control unit and perform precise injection control on their respective service areas.

[0023] The vacuum suction unit is used to achieve pre-vacuuming and dynamic pressure regulation during the liquid injection process of the sterilization chamber. It mainly consists of a vacuum pump unit, a vacuum regulating valve, and a vacuum degree detection module. The vacuum regulating valve adopts a proportional adjustment structure, which can continuously adjust the suction rate according to the control command of the main control unit, and achieve dynamic pressure stability within the chamber in conjunction with the liquid injection and carrier gas introduction processes. The vacuum degree detection module collects the absolute pressure data of the chamber in real time and feeds it back to the main control unit as the core input parameter for pressure closed-loop control and operating condition identification. The suction rate adjustment range of the vacuum suction unit covers the full operating condition requirements of high pumping speed for pre-vacuuming and low pumping speed for steady-state maintenance, and can work in conjunction with the carrier gas supply unit to build a steady-state airflow circulation within the chamber.

[0024] The carrier gas supply unit is used to deliver auxiliary carrier gas that meets the cleanliness and temperature / humidity requirements of the system. It mainly consists of a gas source, a drying module, a sterilization and filtration module, a preheating module, and a flow regulating valve. The carrier gas sequentially passes through the drying module to remove moisture, the sterilization and filtration module to remove microorganisms, and the preheating module to adjust it to the set temperature before being introduced into the vaporization module or the sterilization chamber. Specifically, the drying module lowers the carrier gas dew point below a preset value, preventing the introduction of additional moisture and increasing the risk of condensation. The sterilization and filtration module uses a sterile-grade filter element to ensure the sterility of the carrier gas, meeting the cleanliness requirements of aseptic sterilization scenarios. The preheating module precisely adjusts the carrier gas output temperature, ensuring that the carrier gas temperature and the initial temperature of the chamber are within a preset matching range, preventing condensation caused by a sudden drop in local temperature due to low-temperature carrier gas. The flow regulating valve uses a proportional control structure, which can continuously adjust the carrier gas inlet rate according to the instructions of the main control unit.

[0025] The parameter monitoring unit is used to acquire various sterilization process parameters in real time throughout the entire sterilization process. Monitoring points for collecting data on the internal environment of the sterilization chamber are located at preset positions within the chamber, preferably the most unfavorable positions. The most unfavorable position refers to the area within the sterilization chamber with the lowest temperature, weakest airflow circulation intensity, and greatest likelihood of steam condensation or concentration distribution deviations; these are typically the bottom corners of the chamber or areas obstructed by loads. Using the monitoring data from these preset positions as a control benchmark ensures condensation safety throughout the entire chamber. The sterilization process parameters specifically include two parts: one part consists of internal state parameters collected by sensors at the preset positions, including real-time gas pressure, real-time chamber temperature, hydrogen peroxide gas phase concentration, relative saturation of the mixed steam, dew point temperature of the mixed steam, and the lowest surface temperature of the chamber; the other part consists of operating parameters synchronously acquired by the main control unit from the corresponding actuators of the system, including the hydrogen peroxide injection rate and the carrier gas inlet rate. All parameters are synchronously uploaded to the main control unit at preset sampling intervals.

[0026] The catalytic decomposition and residue removal unit is used to decompose residual hydrogen peroxide in the chamber after sterilization. It mainly consists of a catalytic decomposition module and a gas replacement module. The catalytic decomposition module uses a precious metal catalytic system, which can decompose hydrogen peroxide into water and oxygen at room temperature without secondary pollution. The gas replacement module, in conjunction with vacuum suction and carrier gas introduction, can quickly replace and remove residual sterilizing agent in the chamber, rapidly reducing the residual concentration in the chamber to below the safe threshold.

[0027] After completing system initialization and pretreatment, the sterilization process enters the trial injection and operating condition identification stage. In this stage, small doses of hydrogen peroxide and carrier gas are simultaneously introduced to acquire dynamic response data of the cavity, thereby calculating the spatial characteristic parameters and overall loss coefficient under the current operating conditions. This provides a basis for subsequent precise injection dosage calculation and steady-state control.

[0028] like Figure 2 As shown, in step S1, before initiating the trial injection, the main control unit first activates the vacuum suction unit to evacuate the sterilization chamber to a preset initial vacuum level, preferably an absolute pressure of 70 kPa to 90 kPa. This provides sufficient expansion space for the trial injection while preventing deep vacuum damage to the chamber. Simultaneously, the carrier gas supply unit controls the pretreated carrier gas to be introduced into the chamber at a preset basic flow rate. During this process, the parameter monitoring unit collects chamber temperature and pressure data in real time. When the chamber temperature, humidity, and pressure stabilize to the preset initial operating condition range, the pretreatment operation is completed, and the trial injection phase begins. The introduction of carrier gas during the pretreatment stage is used to pre-stabilize the airflow and temperature fields within the chamber, preventing fluctuations in the initial operating conditions during the trial injection from interfering with the identification accuracy. It also replaces residual water vapor within the chamber, reducing the impact of the initial water vapor partial pressure on subsequent condensation control.

[0029] After pretreatment, the main control unit sends a trial injection command to the evaporation injection unit, controlling it to continuously inject liquid hydrogen peroxide into the cavity at a preset fixed injection rate. The liquid hydrogen peroxide is completely vaporized into a gaseous state by the vaporization module, then thoroughly mixed with the carrier gas and diffuses into the sterilization cavity. During the injection process, the parameter monitoring unit continuously samples the sterilization process parameters according to a preset sampling period, constructing a time-series data sequence reflecting the changes in the sterilization cavity state over time. The sterilization process parameters include the real-time gas pressure, real-time cavity temperature, hydrogen peroxide injection rate, and carrier gas injection rate within the sterilization cavity. All sampled data undergoes time-axis synchronous calibration to ensure consistent time references for each parameter. Simultaneously, it is processed using moving average noise reduction to eliminate sensor noise and transient interference, providing a reliable data foundation for subsequent dynamic response characteristic extraction.

[0030] The main control unit analyzes and processes the acquired time-series data, extracting two core dynamic response features as input for operational condition identification. The first is the real-time pressure change rate. The main control unit performs differential calculations on the real-time pressure time-series data to obtain the rate of pressure change over time, i.e., the real-time pressure change rate. This rate comprehensively reflects the input rate of gaseous substances, the effective volume of the cavity, and the cavity pressure response characteristics under various losses, serving as the core basis for identifying cavity volume and loss levels. The second is the temperature fluctuation gradient. The main control unit extracts the amplitude and rate of change of the real-time cavity temperature during the pressure rise process, obtaining the temperature fluctuation gradient. This gradient reflects the combined effects of hydrogen peroxide vaporization heat absorption, heat carried in by the carrier gas, and heat exchange on the cavity wall. It can be used to correct the impact of temperature changes on the accuracy of pressure identification and indirectly reflects the intensity of wall adsorption and latent heat release. The real-time pressure change rate and temperature fluctuation gradient are combined as the dynamic response characteristics of the sterilization cavity for subsequent parameter identification calculations.

[0031] like Figure 5 As shown, based on the extracted dynamic response characteristics and input process parameters, the main control unit sequentially calculates the spatial characteristic parameters and the comprehensive loss coefficient. First, it calculates the gaseous substance mass expansion rate. Based on the current hydrogen peroxide injection rate, carrier gas inlet rate, and real-time chamber temperature, combined with the molar mass and vaporization expansion characteristics of hydrogen peroxide and carrier gas, it calculates the total increase in the amount of gaseous substance input into the sterilization chamber per unit time, thus obtaining the gaseous substance mass expansion rate under the current operating conditions. The gaseous substance mass expansion rate characterizes the theoretical pressure boosting capability of the input gas per unit time and serves as the benchmark for subsequent volume identification.

[0032] Based on this, the spatial characteristic parameters are calculated. The main control unit extracts the initial lossless maximum rate of change from the real-time pressure change rate curve. This initial lossless maximum rate refers to the maximum instantaneous rate of pressure rise within the very short time after the initial injection, before the loss effects such as wall adsorption, leakage, and decomposition become apparent. This rate approximately reflects the pressure response under lossless conditions. Based on the proportional relationship between the gaseous substance's mass expansion rate and the initial lossless maximum rate, combined with the ideal gas law, the effective physical volume of the sterilization chamber, i.e., the spatial characteristic parameters, is calculated. The spatial characteristic parameters characterize the actual effective space that the chamber can hold for gaseous sterilizing agents, distinct from the nominal volume of the chamber, and accurately reflect the actual gas volume after the load occupies the space.

[0033] Specifically, the increase in the total amount of gaseous substances input into the sterilization chamber per unit time is the gaseous substance mass expansion rate. The calculation formula is:

[0034] In the formula, and These represent the injection rate of liquid hydrogen peroxide and the inlet rate of the carrier gas, respectively. and These represent the densities of the corresponding substances. and These are the molar masses of hydrogen peroxide and the carrier gas, respectively.

[0035] Based on the ideal gas law The spatial characteristic parameters characterizing the effective physical volume of the cavity are calculated using the following formula. :

[0036] In the formula, Let be the ideal gas constant. This represents the absolute temperature value of the real-time cavity temperature. The extracted initial lossless maximum rate is the initial instantaneous rate of increase of the cavity pressure.

[0037] Subsequently, the initial pressure change rate is calculated. Based on the gaseous substance's mass expansion rate and the calculated spatial characteristic parameters, combined with the ideal gas law, the theoretical pressure change rate within the cavity under ideal lossless conditions is calculated as a benchmark value for loss assessment. Finally, the comprehensive loss coefficient is calculated. The difference between the theoretical pressure change rate and the real-time pressure change rate is calculated to obtain the pressure rise attenuation deviation, which reflects the attenuation of the pressure rise caused by various loss effects. Combining the pressure rise attenuation deviation with the temperature fluctuation gradient, a preset parameter identification algorithm is used for fitting and solving to obtain the comprehensive loss coefficient. The comprehensive loss coefficient is used to characterize the concentration attenuation effect caused by the combined effects of cavity wall adsorption, cavity leakage, and natural decomposition of hydrogen peroxide, and can quantify the loss level of the sterilizing agent under the current operating conditions.

[0038] Specifically, the rate of change of initial air pressure The solution formula is:

[0039] After the operating condition identification calculation is completed, the main control unit stores the spatial characteristic parameters and comprehensive loss coefficient under the current operating condition as the basic parameters for subsequent loss compensation dosage calculation and steady-state feedforward control. The trial injection and operating condition identification stage ends.

[0040] In step S2, after completing the trial injection and operating condition identification, the sterilization process enters the loss compensation dosage calculation stage. Based on the spatial characteristic parameters and comprehensive loss coefficient obtained from the aforementioned identification, and combined with the preset target sterilization concentration, this stage determines the amount of fluid to be replenished for the precise injection stage through a loss compensation dosage calculation strategy, providing a dosage basis for subsequent precise injection.

[0041] In the specific calculation process, the reference gas mass required for the sterilization chamber under the target sterilization state is first determined. The main control unit extracts the equivalent volume parameters of the chamber from the spatial characteristic parameters, and combines them with the preset target sterilization concentration (preferably 500ppm to 1500ppm), the preset working temperature of the chamber, and the sub-atmospheric working pressure. Based on the ideal gas law, the total amount of hydrogen peroxide gaseous substance in the chamber under the target sterilization state is calculated, and then the reference gas mass is obtained by converting the molar mass of hydrogen peroxide. This reference gas mass characterizes the total mass of sterilizing agent gaseous phase required to achieve the target hydrogen peroxide concentration in the chamber under ideal conditions without loss. It is the core reference value for dosage calculation. Its calculation process is completely anchored to the actual effective volume of the chamber obtained by identification, which is different from empirical estimation based on nominal volume. It can accurately adapt to the actual gas volume conditions after different loads occupy space.

[0042] Based on this, the mass of compensating gas during the sterilization process is determined. The main control unit extracts three sub-parameters from the comprehensive loss coefficient: wall adsorption coefficient, cavity leakage coefficient, and hydrogen peroxide decomposition coefficient. These are then combined with a preset sterilization holding time, preferably 30 to 120 minutes, to calculate the adsorption loss, leakage loss, and decomposition loss. The adsorption loss corresponds to the concentration decrease caused by the adsorption of gaseous hydrogen peroxide on the cavity wall and load surface; the leakage loss corresponds to the loss of sterilizing agent due to micro-leakage in the cavity sealing structure; and the decomposition loss corresponds to the concentration decrease caused by the thermal and catalytic decomposition of hydrogen peroxide itself. The three types of losses are summed to obtain the mass of compensating gas. This mass is used to offset the continuous concentration decrease throughout the sterilization process, ensuring that the hydrogen peroxide concentration in the cavity remains stably within the target range during the steady-state maintenance phase, preventing the concentration from gradually falling below the sterilization requirements due to continuous loss.

[0043] The final calculated volume of liquid to be replenished is obtained by summing the aforementioned baseline gas mass and compensation gas mass to arrive at the total injection mass required to achieve and maintain the target sterilization concentration. This total injection mass is then subtracted from the cumulative mass of hydrogen peroxide injected during the trial injection phase. The converted liquid volume is the volume of liquid to be replenished required for the precise injection phase. This calculation logic covers the baseline dose to achieve the target concentration, compensates for losses throughout the sterilization process, and deducts the injected volume from the trial phase. The complete closed-loop dose calculation logic effectively avoids problems of insufficient or excessive dose injection.

[0044] Specifically, the volume of fluid to be replenished The computational logic is implemented through the following mathematical model:

[0045]

[0046]

[0047] In the formula, As the reference gas mass, The mass concentration value of the preset target sterilization concentration; To compensate for the gas mass, The preset sterilization duration, , , These are the wall adsorption coefficient, cavity leakage coefficient, and natural decomposition coefficient extracted from the comprehensive loss coefficient, respectively. To test the cumulative mass of hydrogen peroxide injected during the injection phase, This represents the density of liquid hydrogen peroxide. The closed-loop calculation model described above fundamentally ensures the accuracy of the injection dosage.

[0048] In step S3, after the dosage calculation is completed, the sterilization process enters the precise injection and gas path coordinated adjustment stage. The main control unit issues a precise injection command, controlling the evaporation injection unit to inject the aforementioned amount of hydrogen peroxide to be replenished into the sterilization chamber at a preset initial maximum injection rate. Simultaneously, the vacuum suction rate and carrier gas introduction rate are dynamically adjusted to maintain a stable sub-atmospheric pressure operating range within the sterilization chamber and to form a steady-state airflow circulation that matches the current injection process. This adjustment process adopts a control architecture that combines feedforward reference matching with feedback dynamic correction, taking into account both adjustment response speed and steady-state control accuracy.

[0049] In the feedforward reference matching stage, the main control unit calculates the theoretical pressure change rate corresponding to the complete vaporization of liquid hydrogen peroxide based on the current hydrogen peroxide injection rate. Combined with the pressure reference value of the preset sub-atmospheric pressure target range, it matches and determines the vacuum suction reference rate and the carrier gas introduction reference rate. The preset sub-atmospheric pressure target range is preferably an absolute pressure of 85 kPa to 95 kPa, maintaining a slightly negative pressure state to prevent sterilizing agent leakage. The vacuum suction reference rate is used to offset the pressure rise caused by hydrogen peroxide vaporization, maintaining basic pressure stability in the chamber. The carrier gas introduction reference rate is used to drive vapor flow within the chamber, constructing a basic-strength airflow circulation, promoting uniform diffusion of hydrogen peroxide vapor within the chamber, and avoiding localized concentration accumulation. Setting the feedforward reference can preemptively offset pressure disturbances caused by the injection process, significantly reducing the lag and overshoot of subsequent feedback adjustments, and improving the stability of pressure control.

[0050] In the feedback correction phase, the parameter monitoring unit collects real-time pressure data within the sterilization chamber. This data is transmitted to the main control unit, which calculates the actual real-time pressure change rate. Simultaneously, it calculates the deviation between the real-time pressure and the preset sub-atmospheric pressure target range. Both the pressure deviation and the real-time pressure change rate are used as inputs for feedback regulation. Based on these two inputs, the main control unit synchronously corrects the vacuum suction reference rate and the carrier gas injection reference rate, ensuring that the pressure within the sterilization chamber remains stable within the preset sub-atmospheric pressure target range while maintaining the airflow circulation intensity matching the current injection rate. This synchronous correction design means that vacuum suction and carrier gas supply are no longer two independently adjustable parameters, but rather work together to achieve both pressure stability and uniform airflow, thus enabling steady-state control of the gas path.

[0051] The closed-loop control is implemented using a PID control algorithm, which consists of three adjustment stages. The first is the proportional control stage, which generates a proportional control response based on the current magnitude of the pressure deviation. The larger the deviation, the stronger the control response, used to quickly suppress immediate pressure errors and achieve rapid convergence of the deviation. The second is the integral control stage, which generates an integral control response based on the cumulative state of the pressure deviation over time. This stage gradually corrects the persistent steady-state deviation, eliminating steady-state errors and ensuring that the pressure eventually stabilizes within the target pressure range. The third is the derivative control stage, which generates a derivative control response based on the real-time rate of change of pressure. By anticipating the pressure change trend, it applies a reverse control action in advance to suppress pressure fluctuations and overshoot, improving the smoothness of pressure regulation. The proportional, integral, and derivative control responses are integrated to generate a comprehensive control quantity. Based on preset weighting coefficients, the main control unit calculates the comprehensive control quantity into vacuum suction rate correction values ​​and carrier gas inlet rate correction values. The vacuum suction rate correction corresponds to a high weight for pressure regulation, while the carrier gas inlet rate correction corresponds to a high weight for airflow circulation. Finally, the two correction values ​​are superimposed on their respective reference rates, and the final execution command is output. Specifically, the vacuum suction correction weight is preferably set to 0.6–0.8, and the carrier gas inlet correction weight is preferably set to 0.2–0.4.

[0052] like Figure 4As shown, the anti-condensation safety constraint strategy is in effect throughout the entire precision injection process. This constraint is a hard constraint, with higher priority than gas pressure stabilization regulation and injection rate control. When the constraint condition is triggered, the condensation protection action is executed first. The main control unit obtains the relative saturation of the mixed vapor and the lowest surface temperature of the cavity at the preset location in real time through the parameter monitoring unit, and uses these two as condensation constraint parameters. At the same time, it combines the difference between the dew point temperature of the mixed vapor and the lowest surface temperature of the cavity to comprehensively cover the condensation risk of the entire gas phase and local surfaces. Among them, the relative saturation of the mixed vapor reflects the overall condensation trend of the hydrogen peroxide and water vapor mixture, which can intuitively reflect the overall supersaturation risk of the gas phase; the difference between the dew point temperature of the mixed vapor and the lowest surface temperature of the cavity reflects the proximity of condensation on the local surface. The smaller the difference, the more likely condensation will occur on the surface. The two parameters complement each other and can simultaneously cover the condensation risk of the entire gas phase and local surfaces, avoiding the monitoring blind spots of a single parameter.

[0053] When the relative saturation of the mixed vapor reaches a preset upper limit threshold, or the difference between the mixed vapor dew point temperature and the lowest surface temperature of the cavity reaches a preset lower limit threshold, an over-limit protection mechanism is immediately triggered. The preset upper limit threshold is preferably 85%–92% to allow for a safety margin before reaching the dew point; the preset lower limit threshold is preferably 2℃–5℃ to ensure that the vapor dew point is always lower than the coldest surface temperature. The protection mechanism works as follows: the current hydrogen peroxide injection rate is reduced by a preset ratio to decrease the input of gaseous sterilizing agent and reduce the risk of vapor oversaturation from the source; simultaneously, the carrier gas injection rate is increased to strengthen the airflow circulation intensity within the cavity, reducing the local vapor concentration through carrier gas dilution and promoting uniform vapor distribution. The two actions are executed in tandem to quickly reduce the risk of condensation within the cavity. Once both condensation constraint parameters have fallen back to the safe range, the main control unit gradually increases the hydrogen peroxide injection rate to restore the original injection level, ensuring a balance between injection efficiency and condensation safety. When the hydrogen peroxide concentration in the chamber approaches the preset target sterilization concentration, the precise injection phase gradually slows down and ends, providing a basis for a smooth transition in the subsequent steady-state fine-tuning maintenance phase.

[0054] In step S4, when the hydrogen peroxide concentration in the chamber reaches the preset target sterilization concentration, the precise injection phase ends, and the sterilization process enters the steady-state fine-tuning and maintenance phase. The main control unit maintains a dynamic balance between vacuum suction and carrier gas introduction, keeping the sub-atmospheric pressure working range and steady-state airflow circulation within the chamber stable. Simultaneously, based on real-time sterilization process parameters and the comprehensive loss coefficient, a hydrogen peroxide injection compensation strategy is generated. The hydrogen peroxide injection rate is dynamically adjusted according to the compensation strategy to keep the hydrogen peroxide concentration in the chamber stably maintained within the preset target sterilization concentration level until the preset sterilization exposure time requirement is met.

[0055] The hydrogen peroxide injection compensation strategy employs a composite control architecture combining feedforward compensation and feedback correction. The main control unit first calculates the hydrogen peroxide concentration decay per unit time under the current operating conditions based on the identified comprehensive loss coefficient, and then converts this into the feedforward compensation injection amount for the corresponding time period. The feedforward compensation injection amount is used to preemptively offset the continuous concentration decrease caused by adsorption on the chamber wall, chamber leakage, and natural decomposition of hydrogen peroxide, fundamentally compensating for the concentration deviation caused by losses. This significantly reduces the lag in feedback regulation and minimizes steady-state concentration fluctuations. Based on this, the main control unit collects the hydrogen peroxide concentration in the chamber in real time through the parameter monitoring unit, calculates the concentration deviation between the real-time concentration and the preset target sterilization concentration, and calculates the feedback adjustment injection amount based on the concentration deviation. The feedback adjustment injection amount is used to correct the errors in feedforward compensation and the real-time concentration deviation caused by operating condition fluctuations, ensuring that the concentration always falls within the target range. The main control unit superimposes the feedforward compensation injection amount and the feedback adjustment injection amount to generate the fine-tuned injection rate for the corresponding time period, which is then output to the evaporation injection unit for micro-volume replenishment. The steady-state fine-tuning process is also constrained by the aforementioned anti-condensation threshold. When the relative saturation of the mixed steam reaches the preset upper limit threshold, or when the difference between the dew point temperature of the mixed steam and the lowest surface temperature of the cavity reaches the preset lower limit threshold, the main control unit prioritizes to lower the fine-tuning injection rate, and if necessary, simultaneously increases the carrier gas inlet rate until the condensation constraint parameters fall back to the safe range, thereby achieving condensation control without blind spots in the entire sterilization process.

[0056] Once the steady-state maintenance time reaches the preset sterilization exposure time, meeting the microbial kill requirements of the sterilization process, the steady-state fine-tuning maintenance phase ends, and the sterilization process enters the decay and residue removal phase. The main control unit stops hydrogen peroxide injection and simultaneously increases the vacuum suction rate and carrier gas introduction rate, working in conjunction with the catalytic decomposition and residue removal unit to decompose and replace the residual hydrogen peroxide in the chamber. The catalytic decomposition module decomposes gaseous hydrogen peroxide into water and oxygen. Gas path replacement rapidly reduces the residual concentration in the chamber through continuous vacuuming and carrier gas introduction until the residual hydrogen peroxide concentration in the chamber drops below the safe threshold. After residue removal is completed, and after passing concentration detection and biological indicator verification, sterilization and release are completed.

[0057] As a specific implementation method for enclosed spaces, this method is applied to the sterilization process of a 2m³ aseptic filling isolator. This isolator is a completely sealed structure, and the sterilization objective is to achieve a 6-log microbial kill effect. Sterile nitrogen is used as the carrier gas. After the sterilization process is initiated, a pretreatment operation is performed first. The main control unit, in conjunction with the vacuum suction unit, evacuates the isolator cavity to a preset initial vacuum level, while preheated sterile nitrogen is introduced to stabilize the cavity temperature to a preset initial temperature range. After pretreatment, the trial injection and operational condition identification stage begins. The evaporation injection unit injects hydrogen peroxide at a fixed rate, and the parameter monitoring unit continuously collects parameters such as real-time gas pressure, real-time cavity temperature, injection rate, and inlet rate according to a preset sampling period. The main control unit extracts the real-time gas pressure change rate and temperature fluctuation gradient as dynamic response characteristics, and sequentially calculates the spatial characteristic parameters of the cavity's equivalent volume, as well as the comprehensive loss coefficient including wall adsorption, leakage, and decomposition components. After identification, the main control unit calculates the reference gas mass and compensation gas mass using a loss compensation dosage calculation strategy, combined with the preset target sterilization concentration and sterilization holding time. After deducting the cumulative injection volume during the trial phase, the volume of liquid to be replenished is obtained. Then, the precise injection phase begins. The evaporation injection unit injects the required volume of hydrogen peroxide at the initial maximum injection rate. Simultaneously, the main control unit matches the vacuum suction reference rate and carrier gas inlet reference rate according to the injection rate, and uses a PID algorithm to synchronously correct for real-time pressure deviation and pressure change rate, maintaining stability in the sub-atmospheric pressure range of the chamber and uniform airflow circulation. Throughout the injection process, the relative saturation of the mixed vapor and the dew point temperature difference are used as constraints. When parameters exceed limits, the injection rate is automatically reduced and the carrier gas volume is increased to prevent condensation. Once the chamber concentration reaches the target value, the system switches to steady-state fine-tuning mode, maintaining concentration stability through a composite control of feedforward compensation and feedback correction until the preset sterilization holding time is reached. After holding, catalytic residue removal is initiated. Once the residual concentration drops below 1 ppm and passes verification with a biological indicator, sterilization and release are completed. In this scenario, the method can automatically adapt to different load conditions, without the need for manual recalibration of injection parameters, significantly improving batch concentration consistency, and without any condensation throughout the process.

[0058] This method is sensor-independent, and the hardware implementation for parameter monitoring can adopt multiple schemes without changing the core control logic. One implementation scheme uses a composite sensor with an integrated catalyst layer, which can directly output hydrogen peroxide concentration and relative saturation parameters of the mixed steam. Combined with independent temperature and pressure detection modules, all sterilization process parameters can be acquired. Another implementation scheme uses an electrochemical hydrogen peroxide sensor paired with independent temperature and humidity sensors. Through the thermodynamic calculation model built into the main control unit, the relative saturation and dew point temperature parameters of the mixed steam are calculated based on real-time concentration, temperature, and pressure data. A third implementation scheme uses a self-developed multi-parameter composite sensor, which acquires target parameters based on any feasible physical measurement principle. Regardless of the sensor hardware scheme used, the operating condition identification, dosage calculation, gas path coordinated adjustment, anti-condensation constraint, and steady-state composite control logic of this method remain consistent, demonstrating strong hardware adaptability.

[0059] This invention provides a multi-parameter injection control method and system for a hydrogen peroxide space sterilization system. Through a design that automatically identifies the chamber's operating conditions during trial injection, it can automatically adapt to sterilization scenarios with different volumes, loads, and leakage levels, eliminating the need for manual calibration of process parameters and significantly improving the adaptability of the sterilization process. By combining loss-compensation dosage calculation with a feedforward-feedback composite control architecture, precise control of the sterilization dosage can be achieved, resulting in small steady-state concentration fluctuations, high batch consistency, and stable and reliable sterilization effects. Through synchronous linkage adjustment of vacuum suction and carrier gas introduction, the dual control objectives of pressure stability and airflow uniformity are achieved. The carrier gas is no longer merely a transport medium but deeply participates in the entire process of pressure regulation, vapor diffusion, and condensation control, improving the overall control stability of the system. By constraining the entire process using two parameters—relative saturation of the mixed vapor and dew point temperature difference—the risk of condensation on both the overall gas phase and local surfaces can be simultaneously covered, effectively avoiding condensation and reducing the risks of equipment corrosion and sterilizing agent residue. The overall solution adopts a modular design, is compatible with a variety of application scenarios, supports single-unit and multi-unit distributed deployment, is compatible with a variety of sensor hardware solutions, has a wide range of applications, and is highly feasible for engineering implementation.

[0060] The above description is only a preferred embodiment of the technical solution of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A multi-parameter injection control method for a hydrogen peroxide space sterilization system, characterized in that, Includes the following steps: Step S1: After evacuating the sterilization chamber to a preset initial vacuum level, hydrogen peroxide is simultaneously injected into the sterilization chamber and carrier gas is introduced, and sterilization process parameters are acquired in real time during the introduction process; dynamic response characteristics are extracted based on the sterilization process parameters, and spatial characteristic parameters and comprehensive loss coefficient of the sterilization chamber are calculated; Step S2: Based on the spatial characteristic parameters, the comprehensive loss coefficient, and the preset target sterilization concentration, the volume of fluid to be replenished is calculated using a loss compensation dosage calculation strategy; Step S3: Inject the amount of hydrogen peroxide to be replenished into the sterilization chamber; during the injection process, dynamically adjust the vacuum suction rate and carrier gas introduction rate according to the current hydrogen peroxide injection rate and the real-time gas pressure change rate in the sterilization chamber, so that a steady-state airflow circulation matching the current injection process is formed in the sterilization chamber. Step S4: Based on the sterilization process parameters and comprehensive loss coefficient obtained in real time in the sterilization chamber, generate a hydrogen peroxide injection compensation strategy, and dynamically adjust the hydrogen peroxide injection rate according to the compensation strategy to keep the hydrogen peroxide concentration in the sterilization chamber stable within the preset target sterilization concentration level.

2. The multi-parameter injection control method according to claim 1, characterized in that: The sterilization process parameters in step S1 include the real-time gas pressure, real-time chamber temperature, hydrogen peroxide injection rate, and carrier gas introduction rate within the sterilization chamber; the extraction of dynamic response characteristics based on the sterilization process parameters specifically includes: During the hydrogen peroxide injection and carrier gas introduction process, sterilization process parameters are continuously acquired; Based on the continuously acquired sterilization process parameters, the real-time air pressure change rate in the sterilization chamber and the temperature fluctuation gradient during the air pressure rise process are extracted. The real-time air pressure change rate and the temperature fluctuation gradient are used as the dynamic response characteristics.

3. The multi-parameter injection control method according to claim 2, characterized in that, The calculation of the spatial characteristic parameters and overall loss coefficient of the sterilization chamber specifically includes: Based on the hydrogen peroxide injection rate, the carrier gas inlet rate, and the real-time chamber temperature, the mass expansion rate of the gaseous substance currently input into the sterilization chamber is determined. Extract the initial lossless maximum rate from the real-time air pressure change rate, and calculate the spatial characteristic parameters characterizing the effective physical volume of the sterilization chamber based on the proportional relationship between the gaseous substance mass expansion rate and the initial lossless maximum rate. Based on the mass expansion rate of the gaseous substance and the spatial characteristic parameters, the initial pressure change rate is calculated. Based on the initial pressure change rate and the real-time pressure change rate, the pressure rise attenuation deviation is calculated. Based on the pressure rise attenuation deviation and the temperature fluctuation gradient, the comprehensive loss coefficient is calculated to characterize the adsorption, leakage and natural decomposition effects on the cavity wall.

4. The multi-parameter injection control method according to claim 1, characterized in that, The loss compensation dose calculation strategy includes: Based on the spatial characteristic parameters and the preset target sterilization concentration, determine the reference gas mass required for the sterilization chamber to be under the target sterilization state; Based on the comprehensive loss coefficient and the preset sterilization holding time, the mass of compensating gas caused by adsorption, leakage and natural decomposition on the cavity wall during the sterilization process is determined. The mass of the reference gas and the mass of the compensation gas are summed and superimposed to obtain the volume of liquid to be replenished.

5. The multi-parameter injection control method according to claim 1, characterized in that: The process of dynamically adjusting the vacuum suction rate and the carrier gas introduction rate in step S3 specifically includes: Step S31: Calculate the theoretical pressure change rate corresponding to hydrogen peroxide vaporization based on the current hydrogen peroxide injection rate, and match and determine the vacuum suction reference rate and the carrier gas introduction reference rate. Step S32: Obtain the real-time air pressure inside the sterilization chamber and calculate the real-time air pressure change rate; Step S33: Based on the deviation between the real-time air pressure and the preset sub-normal pressure target air pressure range, and the real-time air pressure change rate, the vacuum suction reference rate and the carrier gas introduction reference rate are synchronously and linked for correction.

6. The multi-parameter injection control method according to claim 5, characterized in that: Step S33 specifically includes: calculating the pressure deviation between the real-time air pressure and the preset sub-normal pressure target air pressure range; combining the pressure deviation with the real-time air pressure change rate, generating a vacuum suction rate correction value and a carrier gas inlet rate correction value respectively through a closed-loop control algorithm; superimposing the vacuum suction rate correction value onto the vacuum suction reference rate, and superimposing the carrier gas inlet rate correction value onto the carrier gas inlet reference rate, performing synchronous linkage correction on the two.

7. The multi-parameter injection control method according to claim 6, characterized in that: The execution logic of the closed-loop control algorithm includes: A proportional adjustment response is generated to suppress instantaneous errors based on the current magnitude of the pressure deviation value. An integral control response for eliminating steady-state error is generated based on the cumulative state of the pressure deviation over time. A differential adjustment response is generated based on the real-time pressure change rate to suppress pressure fluctuations; The proportional, integral, and derivative adjustment responses are combined to generate a comprehensive control quantity. Based on the comprehensive control quantity and a preset weighting coefficient, the correction values ​​for the vacuum suction rate and the carrier gas introduction rate are calculated respectively.

8. The multi-parameter injection control method according to claim 1, characterized in that, During the hydrogen peroxide injection process, an anti-condensation safety constraint strategy is also implemented, specifically including: The lowest surface temperature of the sterilization chamber and the relative saturation of the mixed vapor are acquired in real time and used as condensation constraint parameters. When the relative saturation of the mixed vapor reaches a preset upper limit threshold, or the difference between the dew point temperature of the mixed vapor and the lowest surface temperature of the cavity reaches a preset lower limit threshold, the over-limit protection mechanism is triggered, the current hydrogen peroxide injection rate is dynamically reduced, and the carrier gas injection rate is simultaneously increased until the condensation constraint parameter falls back to the safe range.

9. The multi-parameter injection control method according to claim 1, characterized in that: The process of generating the hydrogen peroxide injection compensation strategy in step S4 specifically includes: Based on the comprehensive loss coefficient, the amount of hydrogen peroxide concentration decay per unit time under the current operating conditions is calculated, and the feedforward compensation injection amount is obtained. The real-time concentration of hydrogen peroxide in the sterilization chamber is collected, the concentration deviation between the real-time concentration and the preset target sterilization concentration is calculated, and the injection volume is adjusted based on the concentration deviation. The feedforward compensation injection amount is superimposed with the feedback adjustment injection amount to generate a hydrogen peroxide injection compensation strategy, which is used to output the hydrogen peroxide fine-tuning injection rate for the corresponding time period.

10. A multi-parameter injection control system for a hydrogen peroxide space sterilization system, used to implement the multi-parameter injection control method according to any one of claims 1-9, characterized in that, It includes a main control unit and an evaporation and liquid injection unit, a vacuum suction unit, a carrier gas supply unit, a parameter monitoring unit, and a catalytic decomposition and residue removal unit that are connected to it in communication; the parameter monitoring unit is arranged at a preset position in the sterilization chamber and is used to acquire sterilization process parameters in real time. The main control unit is configured as follows: After the vacuum suction unit is activated to evacuate the sterilization chamber to a preset initial vacuum level, the evaporation injection unit and the carrier gas supply unit are controlled to simultaneously inject hydrogen peroxide into the sterilization chamber and introduce carrier gas, and the spatial characteristic parameters and comprehensive loss coefficient of the sterilization chamber are calculated. The volume of liquid to be injected is determined based on the loss compensation dose calculation strategy. During the injection process, the vacuum suction rate and the carrier gas injection rate are coordinated to construct a steady-state gas flow circulation. An injection compensation strategy is generated by combining feedforward compensation with feedback correction to maintain concentration stability. The evaporation injection unit, vacuum suction unit, and carrier gas supply unit are used to receive instructions from the main control unit and perform injection, suction, and carrier gas introduction actions accordingly. The catalytic decomposition and residue removal unit is used to decompose the residual hydrogen peroxide in the sterilization chamber after sterilization.

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