Control method and system of multi-mode sterilization excimer lamp

Abstract

The invention belongs to the field of control of excimer lamps, and particularly relates to a control method and system of a multi-mode sterilization excimer lamp. The method comprises the following steps: acquiring real-time sampling values of tube current and voltage of the excimer lamp, and determining a current target working mode according to a preset sterilization strategy or an external instruction; the method comprises the following steps: determining an aging characteristic factor by calculating a weighted average value of instantaneous dynamic resistance and equivalent impedance of a lamp tube and combining a lamp tube aging two-dimensional lookup table, and correcting a current reference center line according to the aging characteristic factor; analyzing frequency domain characteristics of the current ripples, and calculating through a preset multivariable function to obtain a dynamic bandwidth of hysteresis control; during mode switching, a dynamic transition period is determined, so that a current reference center line and a target value of a dynamic bandwidth are in smooth transition; and a control signal is generated through the hysteresis comparison current and the dynamic threshold value to control the on-off of the power switch tube. According to the invention, the defects of an existing drive control scheme of the excimer lamp in aging adaptation, mode switching and bandwidth regulation and control are effectively overcome.

Description

Technical Field

[0001] This invention belongs to the field of excimer lamp control, and particularly relates to a control method and system for a multi-mode sterilization excimer lamp. Background Technology

[0002] An excimer lamp is a special type of gas discharge lamp. Its core working principle is to excite a rare gas or a mixture of rare gas and halogen gas inside the lamp tube with high voltage, causing the gas molecules to form an unstable excimer state. When the excimer molecules transition from the excited state to the ground state, they release ultraviolet light of a specific wavelength. This ultraviolet light has strong bactericidal capabilities, thus giving the excimer lamp a certain bactericidal function, which can be used in some applications requiring sterilization.

[0003] The light output power, stability, and lifespan of an excimer lamp largely depend on the performance and control strategy of its driver. Currently, mainstream excimer lamp driver solutions in the industry generally use high-frequency switching converter topologies as the driver power supply, regulating the output power through pulse width modulation control or hysteresis current control to maintain stable operation of the excimer lamp tube. However, existing driver control schemes have the following drawbacks in practical applications: First, during long-term operation, excimer lamps undergo aging due to electrode wear and changes in internal gas composition, leading to alterations in the lamp's current-voltage characteristics, i.e., its equivalent impedance. Existing control schemes use fixed-parameter regulation logic, which cannot adaptively adjust output parameters based on the lamp's real-time aging status. This easily causes the lamp's actual operating point to deviate from its optimal energy efficiency range, resulting not only in decreased light output power and reduced energy efficiency but also accelerated lamp performance degradation due to prolonged operation under suboptimal conditions, thus shortening the excimer lamp's effective lifespan.

[0004] Secondly, excimer lamp sterilization scenarios require different operating modes to meet diverse needs. For example, a preheating mode is needed to quickly activate the lamp during equipment startup, a constant output mode is needed for routine disinfection to ensure stable sterilization effects, and a pulse enhancement mode is needed for deep disinfection in heavily contaminated scenarios. Existing solutions use step-like parameter changes when switching modes, instantly altering the power output state. This can easily generate instantaneous high current or high voltage surges at both ends of the lamp, causing not only drastic fluctuations in light output power and affecting the stability of the sterilization effect, but also potential damage to power switching devices and the lamp itself, increasing the risk of equipment failure.

[0005] Third, while using a fixed hysteresis bandwidth is a compromise, it is difficult to achieve the optimal solution in all modes. This may result in excessive switching losses at some operating points or excessive current ripple at other operating points, making it difficult to achieve a balance between switching losses and current ripple under all operating conditions.

[0006] As can be seen from the above, the shortcomings of existing excimer lamp drive control schemes in terms of aging adaptation, mode switching, and bandwidth regulation have become bottlenecks restricting the improvement of their sterilization performance, equipment reliability, and service life. Summary of the Invention

[0007] Therefore, the purpose of this invention is to provide a control method and system for a multi-mode sterilization excimer lamp, which can effectively solve the defects of existing excimer lamp drive control schemes in terms of aging adaptation, mode switching, and bandwidth regulation.

[0008] To solve the above problems, the present invention provides a technical solution for controlling a multi-mode germicidal excimer lamp: A method for controlling a multi-mode germicidal excimer lamp includes the following steps: Acquire real-time sampled values ​​of the excimer lamp's tube current and tube voltage; determine the current target operating mode from preheating mode, constant output mode, and pulse enhancement mode based on preset sterilization strategies or external commands; The instantaneous dynamic resistance of the lamp and the weighted average of the equivalent impedance within a preset time window are calculated based on the real-time sampled values. The corresponding lamp aging characteristic factor is determined by combining the two in a preset two-dimensional lamp aging lookup table. The current reference value is corrected using the lamp aging characteristic factor to generate the current reference center line for hysteresis comparison. Frequency domain analysis is performed on the lamp current ripple within the sliding window to obtain the amplitude and frequency of the main harmonic component within a preset frequency band. The dynamic bandwidth of hysteresis control is calculated by a preset multivariable function. When a target operating mode switch is detected, a dynamic transition period is determined based on the combination of modes before and after the switch and the lamp aging characteristic factor at the moment of the switch. During the dynamic transition period, the target values ​​of the current reference center line and the dynamic bandwidth follow the Bezier curve trajectory determined by the mode combination, smoothly transitioning from the target value before the switch to the target value after the switch. By combining the current reference centerline and the dynamic bandwidth, the upper and lower threshold values ​​of the hysteresis comparison are calculated; the real-time sampled value of the lamp current is compared with the upper and lower threshold values ​​to generate a control signal for driving the main switch of the excimer lamp power supply.

[0009] Furthermore, the calculation method for the instantaneous dynamic resistance of the lamp and the weighted average of the equivalent impedance within a preset time window is as follows: Lamp voltage at two consecutive sampling times and current The values ​​are calculated by difference, using the formula. Obtain instantaneous dynamic resistance ; Within a preset time window, the equivalent impedance value is obtained by calculating the ratio of the effective values ​​of the lamp voltage and the lamp current. An exponentially weighted moving average is then performed on the continuous equivalent impedance values ​​within the preset time window to obtain the weighted average of the equivalent impedance.

[0010] Furthermore, the method for generating a hysteresis comparison current reference centerline by correcting the current reference value using the lamp aging characteristic factor includes: With the instantaneous dynamic resistance Using the equivalent impedance weighted average as the first input and the equivalent impedance weighted average as the second input, the aging characteristic factor is obtained by indexing a preset two-dimensional lookup table for lamp aging. ; Set the preset current reference value corresponding to the current working mode With the aging characteristic factors Substitute into the formula The center line of the current reference is calculated.

[0011] Furthermore, when the instantaneous dynamic resistance and / or the weighted average of the equivalent impedance do not precisely correspond to the index value of the two-dimensional lookup table, the adjacent row interval where the instantaneous dynamic resistance is located and the adjacent column interval where the weighted average of the equivalent impedance is located are found in the two-dimensional lookup table for lamp aging, respectively, and the four closest known data points in the table are determined. Based on the aging characteristic factors of these four known data points, the aging characteristic factors corresponding to the current first input and second input are calculated by the bilinear interpolation algorithm.

[0012] Furthermore, the step of performing frequency domain analysis on the lamp current ripple within the sliding window to obtain the amplitude and frequency of the main harmonic component within a preset frequency band, and calculating the dynamic bandwidth of the hysteresis control through a preset multivariable function, includes: Perform a fast Fourier transform on the lamp current sampling data within the sliding window to obtain the spectrum of the current ripple; Within a preset frequency band of 20kHz to 100kHz, the dominant harmonic component is searched in the spectrum, and the amplitude of the dominant harmonic component is obtained. With frequency ; Will and Substitute into the preset function Calculate the dynamic bandwidth, where, Based on bandwidth, The gain coefficient is a dimensionless coefficient. This is the frequency response coefficient, with units of current / frequency; This is the reference frequency.

[0013] Furthermore, the process of smoothly transitioning the target values ​​of the current reference centerline and dynamic bandwidth from the target values ​​before the switch to the target values ​​after the switch includes: Based on the source mode before the switch and the target mode after the switch, the transition time is determined from a preset 3D lookup table for mode switching. ; Define a third-order Bézier curve, with the curve's starting point... The parameter values ​​before the switch, the endpoint The target value after the switch, two control points and Set as and and same; exist Time variable The linear increase from 0 to 1 is achieved using the Bézier curve formula. Calculate the instantaneous target values ​​of the current reference centerline and dynamic bandwidth.

[0014] Furthermore, if the aging characteristic factor is obtained through bilinear interpolation and no corresponding transition time is found in the mode switching three-dimensional lookup table, then the final transition time is calculated again using bilinear interpolation on the two sets of indices in the mode switching three-dimensional lookup table that are closest to the aging characteristic factor obtained after the current bilinear interpolation algorithm.

[0015] Furthermore, the calculation methods for the upper and lower thresholds of the hysteresis comparison are as follows: Upper limit threshold ; Lower threshold .

[0016] Furthermore, the process of generating the control signal for driving the main switch transistor of the excimer lamp power supply is as follows: If the main switch is currently in the ON state and the real-time sampled value of the lamp current is greater than or equal to the upper limit threshold, the main switch is turned off. If the main switch is currently off and the real-time sampled value of the lamp current is less than or equal to the lower threshold, the main switch is turned on.

[0017] The technical solution of the control system for a multi-mode germicidal excimer lamp provided by this invention is as follows: A control system for a multi-mode germicidal excimer lamp includes a processor and a memory. The memory stores a computer program, and the processor executes the computer program to implement a control method for a multi-mode germicidal excimer lamp as described in the above-mentioned technical solutions.

[0018] The beneficial effects of this invention are: This invention dynamically corrects the current reference centerline by establishing a lamp aging characteristic factor, actively compensating for the performance degradation caused by lamp aging. This solves the problem that traditional fixed parameters cannot cope with lamp aging, enabling the lamp to maintain a high-efficiency operating range throughout its entire lifespan, ensuring long-term stability of light output power and slowing down lamp performance degradation. During switching between multiple operating modes, a Bezier curve is used to plan the transition trajectory of control parameters, achieving a smooth, shock-free switch from one operating state to another. This suppresses damage to the lamp and power circuit caused by instantaneous mode switching, ensuring stable light power output. Furthermore, this invention sets the hysteresis bandwidth based on the frequency domain characteristics of the lamp current ripple, allowing the control system to automatically find the optimal balance between switching frequency and current ripple under different operating conditions, improving the performance, reliability, and lifespan of the excimer lamp sterilization system. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating a control method for a multi-mode sterilization excimer lamp according to the present invention. Figure 2 This is a structural block diagram of a control system for a multi-mode sterilization excimer lamp according to the present invention. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0021] A specific embodiment of the control method for a multi-mode sterilization excimer lamp of the present invention: like Figure 1 As shown, a control method for a multi-mode germicidal excimer lamp includes the following steps: S1: Acquire real-time sampled values ​​of the excimer lamp's tube current and tube voltage; Determine the current target operating mode from among preheating mode, constant output mode, and pulse enhancement mode based on preset sterilization strategies or external commands. Specifically, in this step, a 20mΩ, 1% precision low-inductance sampling resistor is connected in series in the main power supply circuit, or a Hall current sensor is set to detect the lamp current. A voltage divider network consisting of 470kΩ and 10kΩ resistors is used to acquire the lamp voltage. These two analog signals are input to the controller's 12-bit analog-to-digital converter (ADC) module. The controller performs periodic conversion at a fixed sampling frequency of 100kHz to obtain discrete, digital sequence values ​​of lamp current and lamp voltage.

[0022] Within the controller's internal program, the state machine management operating mode is set. For example, upon startup, the state machine enters a warm-up mode and starts the general-purpose timer TIM2. When the timer reaches a preset value of 30 seconds, it automatically switches to a constant output mode. Simultaneously, the controller continuously monitors the PA0 general-purpose input / output GPIO pin or the serial communication interface UART1. When it receives a specific instruction code from a user key or a host computer, the state machine forcibly switches to pulse enhancement mode.

[0023] S2, calculate the instantaneous dynamic resistance of the lamp and the weighted average of the equivalent impedance within a preset time window based on the real-time sampled value, and determine the corresponding lamp aging characteristic factor in a preset two-dimensional lamp aging lookup table based on the two. Use the lamp aging characteristic factor to correct the current reference value and generate the current reference center line for hysteresis comparison. Perform frequency domain analysis on the lamp current ripple within the sliding window to obtain the amplitude and frequency of the main harmonic component within a preset frequency band, and calculate the dynamic bandwidth of hysteresis control through a preset multivariable function.

[0024] This step involves two parallel tasks: first, calculating an adaptive current reference centerline to compensate for lamp aging effects and ensure stable and efficient light output throughout the lamp's lifespan; and second, calculating an adaptive dynamic bandwidth to optimize the driver power supply's operating performance. By dynamically adjusting the control bandwidth based on actual operating conditions, the optimal balance can be achieved between the driver power supply's switching losses and output current quality, thereby improving the overall system performance.

[0025] Specifically, in this step, the instantaneous dynamic resistance of the lamp and the weighted average of the equivalent impedance within a preset time window are calculated as follows: Lamp voltage at two consecutive sampling times and current The values ​​are calculated by difference, using the formula. Obtain instantaneous dynamic resistance ; Within a preset time window, the equivalent impedance value is obtained by calculating the ratio of the effective values ​​of the lamp voltage and the lamp current. An exponentially weighted moving average is then performed on the continuous equivalent impedance values ​​within the preset time window to obtain the weighted average of the equivalent impedance.

[0026] For example, suppose at time... The lamp voltage was measured to be 150.2V and the lamp current to be 1.98A. At the next sampling time... The measured voltage was 150.5V and the current was 2.01A. The instantaneous dynamic resistance, calculated as the difference between the two voltage values ​​divided by the difference between the two current values, was 10Ω. Within a preset time window of 20 milliseconds, the controller calculated the effective value of the lamp voltage to be 150V and the effective value of the lamp current to be 2.0A, thus obtaining an equivalent impedance of 75Ω for the preset time window. To smooth measurement noise and track long-term impedance trends, an exponentially weighted moving average was used. If the weighted average of the equivalent impedance at the previous moment was 75.5Ω and the weighting factor was 0.1, then the new weighted average of the equivalent impedance would be 75.45Ω.

[0027] In step S2, the method for correcting the current reference value using the lamp aging characteristic factor and generating the current reference center line for hysteresis comparison includes: With the above instantaneous dynamic resistance Using the equivalent impedance weighted average as the first input and the above equivalent impedance weighted average as the second input, the aging characteristic factor is obtained by indexing the preset two-dimensional lookup table for lamp aging. ; Set the preset current reference value corresponding to the current working mode With the aging characteristic factors Substitute into the formula The center line of the current reference is calculated.

[0028] For example, the controller uses the calculated instantaneous dynamic resistance of 10Ω and the weighted average equivalent impedance of 75.45Ω as coordinates to look up a pre-calibrated and stored two-dimensional lookup table for lamp aging. In the lamp aging lookup table, the rows of the matrix correspond to the range of instantaneous dynamic resistance, the columns correspond to the range of the weighted average equivalent impedance, and the values ​​in the table are the aging characteristic factors. For example, looking up the interval containing 10Ω and 75.45Ω, the indexed aging characteristic factor is 0.05. Subsequently, based on the current operating mode of the lamp, such as constant output mode, the preset initial current reference value is 2.0A. The controller substitutes this reference value and the aging characteristic factor of 0.05 obtained from the lookup table into the compensation formula to calculate a new current reference centerline of 2.1A. By monitoring the changes in the lamp's electrical parameters in real time, the current reference can be dynamically increased to compensate for the decrease in luminous efficacy caused by lamp aging and maintain stable light output.

[0029] When the instantaneous dynamic resistance and / or the weighted average of the equivalent impedance do not precisely correspond to the index value in the two-dimensional lookup table, bilinear interpolation is used to calculate and determine the aging characteristic factor, ensuring that the value is accurate and consistent with the actual aging state of the lamp. Specifically, in the lamp aging two-dimensional lookup table, the adjacent row interval containing the instantaneous dynamic resistance and the adjacent column interval containing the weighted average of the equivalent impedance are found respectively. Four closest known data points within the table are determined. Based on the aging characteristic factors of these four known data points, the aging characteristic factor corresponding to the current input value is calculated using a bilinear interpolation algorithm.

[0030] In step S2, the process of performing frequency domain analysis on the lamp current ripple within the sliding window to obtain the amplitude and frequency of the main harmonic component within the preset frequency band, and calculating the dynamic bandwidth of the hysteresis control through a preset multivariable function is as follows: Perform a fast Fourier transform on the lamp current sampling data within the sliding window to obtain the spectrum of the current ripple; Within a preset frequency band of 20kHz to 100kHz, the dominant harmonic component is searched in the spectrum, and the amplitude of the dominant harmonic component is obtained. With frequency ; Will and Substitute into the preset function Calculate the dynamic bandwidth, where, Based on bandwidth, The gain coefficient is a dimensionless coefficient. This is the frequency response coefficient, with units of current / frequency; This is the reference frequency.

[0031] During this process, the controller performs a Fast Fourier Transform on a sliding data window consisting of the most recent 1024 lamp current sampling points to generate a current ripple spectrum. The spectrum is scanned within a frequency range of 20kHz to 100kHz to identify the harmonic components with the largest amplitude. Preferably, the dominant harmonic component is located using the `numpy.argmax()` function. Assuming the analysis results show that the dominant harmonic component has a frequency of 65kHz and a corresponding amplitude of 0.12A, the preferred base bandwidth is set to 0.2A, and the gain coefficient is... The frequency response coefficient is 0.5. The current ripple is 0.002 A / kHz, and the reference frequency is 50 kHz. Substituting these data into the formula yields a dynamic bandwidth of 0.29 A. This dynamic bandwidth adaptively adjusts according to the actual current ripple conditions, ensuring good stability and dynamic performance of the control loop under various operating conditions.

[0032] S3, when a target working mode switch is detected, a dynamic transition period is determined based on the mode combination before and after the switch and the lamp aging characteristic factor at the moment of the switch; within the dynamic transition period, the target values ​​of the current reference center line and the dynamic bandwidth follow the Bezier curve trajectory determined by the mode combination, smoothly transitioning from the target value before the switch to the target value after the switch.

[0033] Since sudden changes in parameters can damage lamps and power supply components, this step ensures the stability and safety of the mode switching process through a smooth transition.

[0034] Specifically, once the controller's mode state variable changes, for example, from constant output mode to pulse enhancement mode, the current lamp aging characteristic factor is read. Using the pre-switch mode, post-switch mode, and lamp aging characteristic factor as indices, a preset three-dimensional lookup table for mode switching is consulted to obtain a transition time, for example, 50 milliseconds. During the next 50-millisecond transition period, the controller initiates an interpolation calculation task. This task uses the pre-switch current reference centerline and dynamic bandwidth as the starting point and the target value of the post-switch mode as the ending point. Based on the mode combination from constant output mode to pulse enhancement mode, the corresponding two control points are retrieved from a preset parameter library. In each control cycle, based on the proportion of the elapsed time to the total transition time, the instantaneous target values ​​of the current reference centerline and dynamic bandwidth are calculated using the third-order Bézier curve formula.

[0035] More specifically, the above process includes: Based on the source mode before the switch and the target mode after the switch, the transition time is determined from a preset 3D lookup table for mode switching. ; Define a third-order Bézier curve, with the curve's starting point... The parameter values ​​before the switch, the endpoint The target value after the switch, two control points and Set as and and same; exist Within a time period, based on the time variable The linear increase from 0 to 1 is achieved using the Bézier curve formula. Calculate the instantaneous target values ​​of the current reference centerline and dynamic bandwidth.

[0036] For example, when a user command switches from a source mode with a power of 80W to a target mode with a power of 120W, the controller queries its internally stored 3D lookup table for mode switching to determine a transition time of 200 milliseconds. Assume the current reference centerline before the switch is 1.8A, and the target value after the switch is 2.5A. At this point, the four control points of the Bézier curve are set, starting at... 1.8A, End Point 2.5A, control point Set as and Same 1.8A, control points Set as and The same 2.5A. For the next 200 milliseconds, the internal timer starts counting from 0. For example, when the transition is halfway through, i.e., 100 milliseconds have elapsed, the time variable... The value is 0.5. The controller calculates the instantaneous target current value at this moment according to the Bézier curve formula, and the result is 2.15A, which is the midpoint between 1.8A and 2.5A. By continuously performing this type of calculation over the entire 200 milliseconds, the current reference centerline will smoothly transition from 1.8A to 2.5A along an S-shaped curve that changes slowly at both ends and more rapidly in the middle, avoiding the impact of sudden current jumps on the lamp and power supply. The dynamic bandwidth parameter also uses the same method for smooth transition, which will not be described in detail here.

[0037] It should be noted that if the aging characteristic factor is obtained by bilinear interpolation and no corresponding transition time is found in the mode switching 3D lookup table, then the two sets of indices in the mode switching 3D lookup table that are closest to the aging characteristic factor obtained by the current bilinear interpolation algorithm will be used again to calculate the final transition time.

[0038] S4. Based on the current reference centerline and the dynamic bandwidth, calculate the upper and lower threshold values ​​for hysteresis comparison; compare the real-time sampled value of the lamp current with the upper and lower threshold values ​​to generate a control signal for driving the main switch of the excimer lamp power supply.

[0039] The controller performs two simple addition and subtraction operations in each control loop. The upper limit threshold is equal to the current effective current reference centerline plus half of the dynamic bandwidth, i.e., the upper limit threshold. The lower limit threshold is equal to the current effective current reference centerline minus half of the dynamic bandwidth, i.e., the lower limit threshold. .

[0040] Based on the dynamically adjusted parameters obtained in the previous steps, assuming the currently calculated current reference centerline is 2.1A and the dynamic bandwidth is 0.29A, to determine the switching point of the hysteresis controller, the upper and lower boundaries of the current fluctuation are further calculated. Half of the dynamic bandwidth, i.e., 0.145A, is calculated. Adding and subtracting this value from the current reference centerline yields the upper threshold of 2.245A and the lower threshold of 1.955A, respectively. The upper and lower thresholds define a current control band around the current reference centerline, and all subsequent switching decisions are based on these two values.

[0041] If the main switch is currently on and the real-time lamp current sample value exceeds the upper threshold, the controller immediately sets the drive signal to low and turns off the main switch. If the main switch is currently off and the real-time lamp current sample value falls below the lower threshold, the controller sets the drive signal to high and turns on the main switch. If the real-time lamp current value is between the upper and lower thresholds, the drive signal remains unchanged, thus forming hysteresis tracking control of the lamp current.

[0042] Assume the main switch of the power supply, such as an IGBT, is currently in the ON state, and the inductor is charging the excimer lamp, causing the lamp current to continuously rise. The controller samples the lamp current at an extremely high frequency, such as once every microsecond. When the sampled value reaches 2.246A at a certain moment, which is greater than the previously calculated upper threshold of 2.245A, the control logic is triggered, generating a low-level signal sent to the gate of the IGBT, causing the IGBT to turn off quickly. After the main switch is turned off, the inductor current begins to decay through the freewheeling diode, and the lamp current decreases accordingly. The controller continues to monitor the lamp current sampled value. When the lamp current sampled value drops to 1.954A, which is less than the lower threshold of 1.955A, the control logic is triggered again, generating a high-level signal sent to the gate of the IGBT, causing it to turn on again and begin the next charging cycle. The on and off cycle repeats continuously, limiting the lamp current to fluctuate between 1.955A and 2.245A.

[0043] A specific embodiment of the control system for a multi-mode germicidal excimer lamp provided by the present invention: like Figure 2 As shown, a control system for a multi-mode germicidal excimer lamp includes a processor and a memory. The memory stores a computer program, which, when executed by the processor, enables the implementation of a control method for a multi-mode germicidal excimer lamp as described in the above embodiments.

[0044] The control system of a multi-mode sterilization excimer lamp also includes other components well known to those skilled in the art, such as a communication bus and a communication interface. Their settings and functions are known in the art and will not be described in detail here.

[0045] In this invention, the aforementioned memory can be any tangible medium containing or storing a program that can be used or combined with an instruction execution system, apparatus, or device. For example, a computer-readable storage medium can be any suitable magnetic or magneto-optical storage medium, such as resistive random access memory (RRAM), dynamic random access memory (DRAM), static random access memory (SRAM), enhanced dynamic random access memory (EDRAM), high-bandwidth memory (HBM), hybrid memory cube (HMC), etc., or any other medium that can be used to store desired information and can be accessed by an application, module, or both. Any such computer storage medium can be part of a device or accessible to or connected to a device.

[0046] While various embodiments of the invention have been shown and described in this specification, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many modifications, alterations, and alternatives will occur to those skilled in the art without departing from the spirit and essence of the invention.

Claims

1. A control method of a multi-mode germicidal excimer lamp, characterized by, Includes the following steps: Obtain real-time sampled values ​​of the excimer lamp's tube current and tube voltage; Based on the preset sterilization strategy or external instructions, determine the current target working mode from the preheating mode, constant output mode and pulse enhancement mode; The instantaneous dynamic resistance of the lamp and the weighted average of the equivalent impedance within a preset time window are calculated based on the real-time sampled values. The corresponding lamp aging characteristic factor is determined by combining the two in a preset two-dimensional lamp aging lookup table. The current reference value is corrected using the lamp aging characteristic factor to generate the current reference center line for hysteresis comparison. Frequency domain analysis is performed on the lamp current ripple within the sliding window to obtain the amplitude and frequency of the main harmonic component within a preset frequency band. The dynamic bandwidth of hysteresis control is calculated by a preset multivariable function. When a target operating mode switch is detected, a dynamic transition period is determined based on the combination of modes before and after the switch and the lamp aging characteristic factor at the moment of the switch. During the dynamic transition period, the target values ​​of the current reference center line and the dynamic bandwidth follow the Bezier curve trajectory determined by the mode combination, smoothly transitioning from the target value before the switch to the target value after the switch. By combining the current reference centerline and the dynamic bandwidth, the upper and lower threshold values ​​of the hysteresis comparison are calculated; the real-time sampled value of the lamp current is compared with the upper and lower threshold values ​​to generate a control signal for driving the main switch of the excimer lamp power supply.

2. The method of claim 1, wherein the method further comprises: The calculation methods for the instantaneous dynamic resistance of the lamp and the weighted average of the equivalent impedance within a preset time window are as follows: Lamp voltage at two consecutive sampling times and current The values ​​are calculated by difference, using the formula. Obtain instantaneous dynamic resistance ; Within a preset time window, the equivalent impedance value is obtained by calculating the ratio of the effective values ​​of the lamp voltage and the lamp current. An exponentially weighted moving average is then performed on the continuous equivalent impedance values ​​within the preset time window to obtain the weighted average of the equivalent impedance.

3. The method of claim 2, wherein the method further comprises: The method for generating a hysteresis comparison current reference centerline by correcting the current reference value using the lamp aging characteristic factor includes: with said instantaneous dynamic resistance as a first input, and said equivalent impedance weighted average as a second input, to index a pre-set two-dimensional look-up table of lamp aging characteristics ; corresponding to the current working mode and the aging characteristic factor substitute into the formula , the current reference center line is calculated.

4. The control method for a multi-mode sterilization excimer lamp according to claim 3, characterized in that, When the instantaneous dynamic resistance and / or the weighted average of the equivalent impedance do not precisely correspond to the index value of the two-dimensional lookup table, the adjacent row interval where the instantaneous dynamic resistance is located and the adjacent column interval where the weighted average of the equivalent impedance is located are found in the two-dimensional lookup table of lamp aging. The four closest known data points in the table are determined. Based on the aging characteristic factors of these four known data points, the aging characteristic factors corresponding to the current first input and second input are calculated by the bilinear interpolation algorithm.

5. The control method for a multi-mode sterilization excimer lamp according to claim 3, characterized in that, The step of performing frequency domain analysis on the lamp current ripple within the sliding window to obtain the amplitude and frequency of the main harmonic component within a preset frequency band, and calculating the dynamic bandwidth of the hysteresis control through a preset multivariable function, includes: Perform a fast Fourier transform on the lamp current sampling data within the sliding window to obtain the spectrum of the current ripple; Within a preset frequency band of 20kHz to 100kHz, the dominant harmonic component is searched in the spectrum, and the amplitude of the dominant harmonic component is obtained. With frequency ; Will and Substitute into the preset function Calculate the dynamic bandwidth, where, Based on bandwidth, The gain coefficient is a dimensionless coefficient. This is the frequency response coefficient, with units of current / frequency; This is the reference frequency.

6. The control method for a multi-mode germicidal excimer lamp according to claim 4, characterized in that, The process of smoothly transitioning the target values ​​of the current reference centerline and dynamic bandwidth from the target values ​​before the switch to the target values ​​after the switch includes: Based on the source mode before the switch and the target mode after the switch, the transition time is determined from a preset 3D lookup table for mode switching. ; Define a third-order Bézier curve, with the curve's starting point... The parameter values ​​before the switch, the endpoint The target value after the switch, two control points and Set as and and same; exist Time variable The linear increase from 0 to 1 is achieved using the Bézier curve formula. Calculate the instantaneous target values ​​of the current reference centerline and dynamic bandwidth.

7. The control method for the multi-mode sterilization excimer lamp according to claim 6, characterized in that, If the aging characteristic factor is obtained through bilinear interpolation and no corresponding transition time is found in the mode switching 3D lookup table, then the final transition time is calculated again using bilinear interpolation on the two sets of indices in the mode switching 3D lookup table that are closest to the aging characteristic factor obtained after the current bilinear interpolation algorithm.

8. The control method for a multi-mode sterilization excimer lamp according to claim 5, characterized in that, The calculation methods for the upper and lower thresholds of hysteresis comparison are as follows: Upper limit threshold ; Lower threshold .

9. The control method for a multi-mode sterilization excimer lamp according to claim 8, characterized in that, The process of generating the control signal for the main switch transistor driving the excimer lamp power supply is as follows: If the main switch is currently in the ON state and the real-time sampled value of the lamp current is greater than or equal to the upper limit threshold, the main switch is turned off. If the main switch is currently off and the real-time sampled value of the lamp current is less than or equal to the lower threshold, the main switch is turned on.

10. A control system for a multi-mode germicidal excimer lamp, characterized in that, It includes a processor and a memory, the memory storing a computer program, and the processor executing the computer program to implement the control method of a multi-mode bactericidal excimer lamp as described in any one of claims 1 to 9.

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