Method and system for controlling a multi-mode germicidal excimer lamp

Abstract

The present application belongs to the field of control of excimer lamps, and particularly relates to a control method and system of a multi-mode germicidal excimer lamp. The method comprises: acquiring real-time sampling values of lamp tube current and voltage of the excimer lamp, determining a current target working mode according to a preset germicidal strategy or external instruction; determining an aging characteristic factor by calculating a lamp tube instantaneous dynamic resistance and an equivalent impedance weighted average value, and combining a lamp tube aging two-dimensional lookup table, and correcting a current reference center line according to the aging characteristic factor; analyzing current ripple frequency domain characteristics, and calculating a dynamic bandwidth of hysteresis control through a preset multivariate function; determining a dynamic transition period when mode switching, so that the target values of the current reference center line and the dynamic bandwidth are smoothly transitioned; and generating a control signal by comparing the current with a dynamic threshold value, and controlling the on-off of a power switch tube. The present application effectively solves the defects of the existing driving control scheme of excimer lamps in aging adaptation, mode switching and bandwidth regulation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of control of excimer lamps, and particularly relates to a control method and system of a multi-mode germicidal excimer lamp. BACKGROUND

[0002] An excimer lamp is a special gas discharge lamp, and its core working principle is to excite the rare gas or the mixed gas of the rare gas and halogen in the lamp tube by high voltage, so that the gas molecules form an unstable excimer state. When the excimer transitions from the excited state to the ground state, it releases ultraviolet light of a specific wavelength. This ultraviolet light has strong sterilization ability, and thus the excimer lamp has certain sterilization function and is applied in some occasions requiring sterilization.

[0003] The light output power, stability and service life of the excimer lamp depend to a large extent on the performance and control strategy of the driving power supply of the excimer lamp. The mainstream excimer lamp driving scheme in the industry generally adopts a high-frequency switching converter topology as the driving power supply, and adjusts the output power by pulse width modulation control or hysteresis current control, etc. to maintain the stable operation of the excimer lamp tube. However, the existing driving control scheme has the following defects in actual application:

[0004] Firstly, during the long-term lighting process of the excimer lamp, the lamp tube will appear aging phenomenon due to electrode wear and change of internal gas composition, resulting in change of the volt-ampere characteristic, i.e. equivalent impedance of the lamp tube. The existing control scheme adopts fixed parameter regulation logic and cannot adaptively adjust the output parameters according to the real-time aging state of the lamp tube, which is easy to make the actual working point of the lamp tube deviate from the optimal energy efficiency region, not only causing the light output power to decrease and the energy efficiency to decrease, but also accelerating the performance degradation of the lamp tube and shortening the effective service life of the excimer lamp due to long-term operation in non-optimal working condition.

[0005] Secondly, the excimer lamp sterilization scene needs to match different working modes to realize differentiated requirements, for example: the preheating mode is needed to quickly activate the lamp tube during the device startup stage, the constant output mode is needed to ensure stable sterilization effect in the conventional disinfection scene, and the pulse enhancement mode is needed to realize deep sterilization in the heavy pollution scene. The existing scheme adopts step parameter change when switching modes, and instantaneously changes the output state of the power supply, which is easy to produce instantaneous high current or high voltage impact at both ends of the lamp tube, not only causing the light output power to fluctuate sharply and affecting the stability of the sterilization effect, but also possibly causing damage to the power switch device and the lamp tube itself, increasing the risk of equipment failure.

[0006] Thirdly, although the fixed hysteresis bandwidth is a kind of compromise scheme, it is difficult to achieve the best in all modes, which may cause excessive switching loss at some working points or excessive current ripple at other working points, and it is difficult to balance the switching loss and current ripple in all working conditions.

[0007] From the above, the defects of the existing excimer lamp driving control scheme in aging adaptation, mode switching and bandwidth regulation have become the bottleneck restricting the improvement of its sterilization performance, device reliability and service life. SUMMARY

[0008] In view of this, the purpose of the present application is to provide a multi-mode sterilization excimer lamp control method and system, which can effectively solve the defects of the existing excimer lamp driving control scheme in aging adaptation, mode switching and bandwidth regulation.

[0009] To solve the above problems, the technical scheme of a multi-mode sterilization excimer lamp control method provided by the present application is:

[0010] A multi-mode sterilization excimer lamp control method, comprising the following steps:

[0011] Obtain the real-time sampling values of the lamp current and lamp voltage of the excimer lamp; according to a preset sterilization strategy or external instruction, determine the current target working mode among the preheating mode, constant output mode and pulse enhancement mode;

[0012] According to the real-time sampling values, calculate the instantaneous dynamic resistance of the lamp and the weighted average value of the equivalent impedance within a preset time window, and determine the corresponding lamp aging characteristic factor in the preset lamp aging two-dimensional lookup table by combining the two, use the lamp aging characteristic factor to correct the current reference value, generate the current reference center line of hysteresis comparison; perform frequency domain analysis on the lamp current ripple within the sliding window, obtain the amplitude and frequency of the main harmonic component within the preset frequency band, and calculate the dynamic bandwidth of hysteresis control through a preset multivariate function;

[0013] When the target working mode switching is detected, determine the dynamic transition period according to the mode combination before and after the switching and the lamp aging characteristic factor at the switching instant; within the dynamic transition period, the current reference center line and the target value of the dynamic bandwidth follow the Bezier curve trajectory determined by the mode combination, and smoothly transition from the target value before the switching to the target value after the switching;

[0014] Combine the current reference center line and the dynamic bandwidth to calculate the upper and lower threshold values of hysteresis comparison; compare the real-time sampling value of the lamp current with the upper and lower threshold values to generate the control signal of the main switch tube of the excimer lamp power supply.

[0015] Further, the calculation method of the instantaneous dynamic resistance of the lamp and the weighted average value of the equivalent impedance within a preset time window is:

[0016] Differential calculation is performed on the lamp voltage and current values at two consecutive sampling moments, and the formula obtaining the instantaneous dynamic resistance ;

[0017] In a preset time window, an equivalent impedance value is obtained by calculating the ratio of the effective value of the lamp voltage and the effective value of the lamp current, and an equivalent impedance weighted average value is obtained by performing an exponentially weighted moving average on the continuous equivalent impedance values in the preset time window.

[0018] Further, the method for generating the hysteresis comparison current reference center line by correcting the current reference value using the lamp aging characteristic factor comprises:

[0019] using the instantaneous dynamic resistance as the first input and using the equivalent impedance weighted average value as the second input, indexing a preset lamp aging two-dimensional lookup table to obtain an aging characteristic factor ;

[0020] substituting the preset current reference value corresponding to the current working mode and the aging characteristic factor into the formula to calculate the current reference center line.

[0021] Further, when the instantaneous dynamic resistance and / or the equivalent impedance weighted average value does not accurately correspond to the two-dimensional lookup table index value, in the lamp aging two-dimensional lookup table, the adjacent row interval where the instantaneous dynamic resistance is located and the adjacent column interval where the equivalent impedance weighted average value is located are found respectively, four closest known data points in the table are determined, and the aging characteristic factor corresponding to the current first input and second input is calculated based on the aging characteristic factors of the four known data points through a bilinear interpolation algorithm.

[0022] Further, the frequency domain analysis of the lamp current ripple in the sliding window is performed to obtain the amplitude and frequency of the main harmonic component in a preset frequency band, and the dynamic bandwidth of the hysteresis control is calculated through a preset multivariate function, comprising:

[0023] performing a fast Fourier transform on the lamp current sampling data in the sliding window to obtain the frequency spectrum of the current ripple;

[0024] in a preset frequency band of 20 kHz to 100 kHz, searching for the main harmonic component in the frequency spectrum to obtain the amplitude and the frequency of the main harmonic component;

[0025] substituting the amplitude and the frequency into the preset function to calculate the dynamic bandwidth, wherein, is a basic bandwidth, is a dimensionless gain coefficient; is the frequency response coefficient, unit: current / frequency; is the reference frequency.

[0026] Further, the process of smoothly transitioning the current reference center line and the target value of the dynamic bandwidth from the target value before switching to the target value after switching includes:

[0027] According to the source mode before switching and the target mode after switching, determine the transition time from the preset mode switching three-dimensional lookup table ;

[0028] Set a third-order Bezier curve, the starting point of the curve is the parameter value before switching, the end point is the target value after switching, and the two control points and are respectively set to be the same as and ;

[0029] Within time, the time variable linearly increases from 0 to 1, and the instantaneous target value of the current reference center line and the dynamic bandwidth is calculated through the Bezier curve formula .

[0030] Further, if the aging characteristic factor is obtained by a bilinear interpolation algorithm, and the corresponding transition time cannot be found in the mode switching three-dimensional lookup table, then the two groups of indexes closest to the aging characteristic factor obtained by the bilinear interpolation algorithm are found in the mode switching three-dimensional lookup table, and the bilinear interpolation algorithm is used again to calculate the final transition time.

[0031] Further, the calculation method of the upper threshold and the lower threshold of the hysteresis comparison is respectively:

[0032] The upper threshold ;

[0033] The lower threshold .

[0034] Further, the generation process of the control signal of the main switch tube of the driving excimer lamp power supply is:

[0035] If the current main switch tube is in the on state, and the real-time sampling value of the lamp current is greater than or equal to the upper threshold, turn off the main switch tube;

[0036] If the current main switch tube is in the off state, and the real-time sampling value of the lamp current is less than or equal to the lower threshold, turn on the main switch tube.

[0037] The technical scheme of the multi-mode germicidal excimer lamp control system provided by the application is:

[0038] The application discloses a control system of a multi-mode germicidal excimer lamp.

[0039] The application has the following beneficial effects:

[0040] The application establishes a lamp tube aging characteristic factor to dynamically correct a current reference center line, actively compensates performance degradation of the lamp tube caused by aging, solves the problem that a traditional fixed parameter cannot cope with lamp tube aging, enables the lamp tube to be kept in a high-efficiency working interval in different stages of the whole life cycle, guarantees long-term stability of light output power, and delays performance degradation of the lamp tube. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 FIG. 1 is a flowchart of a multi-mode germicidal excimer lamp control method according to the application;

[0042] Figure 2 FIG. 2 is a structural block diagram of a multi-mode germicidal excimer lamp control system according to the application. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the application will be clearly and completely described in combination with the accompanying drawings in the embodiments of the application.

[0044] A specific embodiment of the multi-mode germicidal excimer lamp control method according to the application is as follows:

[0045] As shown in FIG. 1, a multi-mode germicidal excimer lamp control method comprises the following steps: Figure 1 S1, acquiring real-time sampling values of lamp tube current and lamp tube voltage of the excimer lamp; determining a current target working mode in a preheating mode, a constant output mode and a pulse enhancement mode according to a preset germicidal strategy or an external instruction;

[0046] S1, acquiring real-time sampling values of lamp tube current and lamp tube voltage of the excimer lamp; determining a current target working mode in a preheating mode, a constant output mode and a pulse enhancement mode according to a preset germicidal strategy or an external instruction;

[0047] Specifically, in this step, a 20 mΩ, 1% precision low inductance sampling resistor is connected in series in the main circuit of the power supply or a Hall current sensor is arranged to detect the lamp current, and a voltage dividing resistor network composed of 470 kΩ and 10 kΩ resistors is used to collect the lamp voltage. The two analog signals are input to the 12-bit analog-to-digital conversion ADC module of the controller, and the controller periodically converts at a fixed sampling frequency of 100 kHz to obtain discrete digitized lamp current and lamp voltage sequence values.

[0048] In the internal program of the controller, a state machine is arranged to manage the working modes. For example, after starting, the state machine enters the preheating mode and starts a general timer TIM2, and when the timer reaches the preset value of 30 seconds, it is automatically switched to the constant output mode. At the same time, the controller continuously monitors the PA0 general input / output GPIO pin or the serial communication interface UART1, and when receiving a specific instruction code from the user key or the upper computer, the state machine is forced to switch to the pulse enhancement mode.

[0049] S2, according to the real-time sampling values, the instantaneous dynamic resistance of the lamp and the weighted average value of the equivalent impedance in the preset time window are calculated, and the corresponding lamp aging characteristic factor is determined in the preset lamp aging two-dimensional lookup table by combining the two, the lamp aging characteristic factor is used to correct the current reference value, and the hysteresis comparison current reference center line is generated; the frequency domain analysis of the lamp current ripple in the sliding window is performed, the amplitude and frequency of the main harmonic component in the preset frequency band are obtained, and the dynamic bandwidth of the hysteresis control is calculated through the preset multivariate function.

[0050] This step includes two parallel tasks, one is to calculate the adaptive current reference center line to compensate for the lamp aging effect and ensure that the lamp can maintain stable and efficient light output throughout its life cycle; the other is to calculate the adaptive dynamic bandwidth to optimize the operating performance of the driving power supply, dynamically adjust the control bandwidth according to the actual working conditions, and achieve the best balance between the switching loss of the driving power supply and the output current quality, thereby improving the overall performance of the system.

[0051] Specifically, in this step, the calculation method of the instantaneous dynamic resistance of the lamp and the weighted average value of the equivalent impedance in the preset time window is as follows:

[0052] The lamp voltage values at two consecutive sampling times are differentiated and the current values are differentiated, and the instantaneous dynamic resistance is obtained by using the formula ;

[0053] In the 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, and the weighted average value of the equivalent impedance is obtained by exponentially weighted moving average of the continuous equivalent impedance values in the preset time window.

[0054] Suppose that at time t0 The lamp voltage is measured as 150.2 V, and the lamp current is measured as 1.98 A at the next sampling time t0+1 The voltage is measured as 150.5 V, and the current is measured as 2.01 A. The instantaneous dynamic resistance is calculated as the difference between the two voltages divided by the difference between the two currents, which is 10 Ω. Within a preset time window of 20 ms, the controller calculates the effective value of the lamp voltage as 150 V and the effective value of the lamp current as 2.0 A, and thus the equivalent impedance of the preset time window is 75 Ω. To smooth the measurement noise and track the long-term trend of the impedance, an exponentially weighted moving average is used. If the weighted average of the equivalent impedance at the previous time is 75.5 Ω, and the weighted factor is 0.1, then the new weighted average of the equivalent impedance is 75.45 Ω.

[0055] In step S2, the method for generating the current reference center line of the hysteresis comparison by using the lamp aging characteristic factor to correct the current reference value includes:

[0056] The above-mentioned instantaneous dynamic resistance As the first input, the above-mentioned weighted average of the equivalent impedance is used as the second input, and the aging characteristic factor is indexed in the preset lamp aging two-dimensional lookup table ;

[0057] The preset current reference value corresponding to the current working mode is substituted into the formula , and the current reference center line is calculated.

[0058] Suppose that the controller uses the above-mentioned calculated instantaneous dynamic resistance 10 Ω and the weighted average of the equivalent impedance 75.45 Ω as the coordinates to query in a lamp aging two-dimensional lookup table that is pre-calibrated and stored through experiments. In the lamp aging two-dimensional lookup table, the rows of the matrix correspond to the range of the instantaneous dynamic resistance, the columns correspond to the range of the weighted average of the equivalent impedance, and the values in the table are the aging characteristic factors. For example, the interval of 10 Ω and 75.45 Ω is queried, and the indexed aging characteristic factor is 0.05. Then, according to the current working mode of the lamp, such as the constant output mode, the preset initial current reference value is 2.0 A. The controller substitutes this reference value and the aging characteristic factor 0.05 obtained by the lookup table into the compensation formula, and calculates the new current reference center line as 2.1 A. By monitoring the changes of the lamp electrical parameters in real time, the current reference can be dynamically improved to compensate for the decrease in luminous efficiency caused by lamp aging, and the stable light output is maintained.

[0059] ​When the instantaneous dynamic resistance and / or the weighted average of the equivalent impedance does not accurately correspond to the index value of the two-dimensional lookup table, a bilinear interpolation calculation is used to determine the aging characteristic factor, ensuring accurate value taking and conforming to the actual aging state of the lamp. The specific way is: first, in the lamp aging two-dimensional lookup table, find 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, determine the four closest known data points in the table, and based on the aging characteristic factor of the above four known data points, the aging characteristic factor corresponding to the current input value is calculated by the bilinear interpolation algorithm.

[0060] In step S2, the lamp current ripple in the sliding window is analyzed in the frequency domain to obtain the amplitude and frequency of the main harmonic component in the preset frequency band. The process of calculating the dynamic bandwidth of the hysteresis control through the preset multivariate function is as follows:

[0061] Performing fast Fourier transform on the lamp current sampling data in the sliding window to obtain the frequency spectrum of the current ripple;

[0062] In the preset frequency band of 20kHz to 100kHz, search for the main harmonic component in the frequency spectrum to obtain the amplitude and frequency of the main harmonic component ;

[0063] Substitute and into the preset function to calculate the dynamic bandwidth, where is the base bandwidth, is the dimensionless gain coefficient; is the frequency response coefficient, with the unit of current / frequency; is the reference frequency.

[0064] In this process, the controller performs fast Fourier transform on the sliding data window composed of the last 1024 lamp current sampling points to generate a current ripple frequency spectrum. In the frequency range of 20kHz to 100kHz, the spectrum is scanned to identify the harmonic component with the largest amplitude, preferably by using the numpy.argmax() function to locate the main harmonic component. Assuming that the analysis result shows that the frequency of the main harmonic component is 65kHz, the corresponding amplitude is 0.12A, the preferred base bandwidth is set to 0.2A, the gain coefficient is 0.5, the frequency response coefficient is 0.002A / kHz, and the reference frequency is 50kHz. Substituting the above data into the formula can obtain the dynamic bandwidth of 0.29A. The dynamic bandwidth can be adaptively adjusted according to the actual current ripple state, ensuring that the control loop has good stability and dynamic performance under different working conditions.

[0065] ​S3, when detecting the target working mode switching, determining a dynamic transition period according to the mode combination before and after the switching and the lamp aging characteristic factor at the switching moment; in the dynamic transition period, the target values of the current reference center line and the dynamic bandwidth follow a Bezier curve trajectory determined by the mode combination, and are smoothly transitioned from the target values before the switching to the target values after the switching.

[0066] Since the instantaneous jump of the parameters will damage the lamp and the power supply device, this step ensures the stability and safety of the mode switching process by means of smooth transition.

[0067] Specifically, once the mode state variable of the controller changes, for example, from the constant output mode to the pulse enhancement mode, the current lamp aging characteristic factor is read. With the mode before the switching, the mode after the switching and the lamp aging characteristic factor as indexes, a preset mode switching three-dimensional lookup table is inquired to obtain a transition time, for example, 50 milliseconds. In the next 50-millisecond transition period, the controller starts an interpolation calculation task, which uses the current reference center line and the dynamic bandwidth before the switching as the starting point and the target values of the mode after the switching as the terminal point. According to the mode combination from the constant output mode to the pulse enhancement mode, two control points are called from the preset parameter library. In each control period, according to the proportion of the time that has passed to the total transition time, the instantaneous target values of the current reference center line and the dynamic bandwidth can be calculated by using the third-order Bezier curve formula.

[0068] More specifically, the above process includes:

[0069] determining the transition time from the source mode before the switching and the target mode after the switching in the preset mode switching three-dimensional lookup table ;

[0070] setting a third-order Bezier curve, the starting point of the curve being the parameter value before the switching, the terminal point being the target value after the switching, and the two control points and being respectively set to be the same as and ;

[0071] in the time, according to the time variable linearly increasing from 0 to 1, the instantaneous target values of the current reference center line and the dynamic bandwidth are calculated by using the Bezier curve formula .

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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 threshold is equal to the current effective current reference centerline minus half of the dynamic bandwidth, i.e., the lower threshold. .

[0076] Based on the dynamically adjusted parameters obtained in the previous step, assuming that the current calculated current reference center line is 2.1A and the dynamic bandwidth is 0.29A. In order to determine the switching point of the hysteresis controller, the upper and lower boundaries of the current fluctuation are further calculated, and half of the dynamic bandwidth is calculated, that is, 0.145A. Add and subtract this value from the current reference center line to obtain the upper threshold value 2.245A and the lower threshold value 1.955A respectively. The upper threshold value and the lower threshold value define a current control band around the current reference center line, and all subsequent switching decisions are made based on these two values.

[0077] If the current main switch tube is in the on state, and the real-time collected lamp current sampling value crosses the upper threshold value, the controller immediately sets the drive signal to low to turn off the main switch tube of the power supply. If the current main switch tube is in the off state, and the real-time collected lamp current sampling value crosses the lower threshold value, the controller sets the drive signal to high to turn on the main switch tube of the power supply. If the real-time collected lamp current value is between the upper and lower threshold values, the drive signal remains unchanged from the previous state, forming a hysteresis tracking control of the lamp current.

[0078] Assuming that the main switch tube of the power supply, for example an IGBT, is currently in the on state, and the inductor is charging the excimer lamp, causing the lamp current to continue to rise. The controller samples the lamp current at a very high frequency, such as once every microsecond. When the sampling value at a certain time reaches 2.246A, which is greater than the previously calculated upper threshold value 2.245A, the control logic triggers and generates a low-level signal to the gate of the IGBT, causing the IGBT to turn off quickly. After the main switch tube 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 sampling value, and when the lamp current sampling value drops to 1.954A, which is less than the lower threshold value 1.955A, the control logic triggers again to generate a high-level signal to the gate of the IGBT, causing it to turn on again and start the next charging period. The on-off cycle is repeated to limit the lamp current to fluctuate between 1.955A and 2.245A.

[0079] The present application provides a specific embodiment of a multi-mode germicidal excimer lamp control system:

[0080] As shown in Figure 2 A multi-mode germicidal excimer lamp control system, comprising a processor and a memory, the memory storing a computer program, when the computer program is executed by the processor, it can realize the control method of the multi-mode germicidal excimer lamp in the above embodiments.

[0081] 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.

[0082] 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.

[0083] 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, The method comprises the following steps: obtaining real-time sampling values of lamp tube current and lamp tube voltage of an excimer lamp; determining a current target working mode from among a preheating mode, a constant output mode and a pulse enhancement mode according to a preset sterilization strategy or external instructions; calculating an instantaneous dynamic resistance of the lamp tube and a weighted average value of equivalent impedance within a preset time window according to the real-time sampling values, and determining a corresponding lamp tube aging characteristic factor in a preset lamp tube aging two-dimensional lookup table by combining the two, correcting a current reference value by using the lamp tube aging characteristic factor, and generating a hysteresis comparison current reference center line; performing frequency domain analysis on lamp tube current ripple within a sliding window to obtain amplitudes and frequencies of main harmonic components within a preset frequency band, and calculating a dynamic bandwidth of hysteresis control by using a preset multivariate function; when a target working mode switching is detected, determining a dynamic transition period according to a mode combination before and after the switching and the lamp tube aging characteristic factor at the switching moment; within the dynamic transition period, target values of the current reference center line and the dynamic bandwidth follow a Bezier curve trajectory determined by the mode combination to smoothly transition from target values before the switching to target values after the switching; combining the current reference center line and the dynamic bandwidth to calculate upper and lower threshold values of the hysteresis comparison; comparing the real-time sampling values of the lamp tube current with the upper and lower threshold values to generate a control signal of a main switch tube of an excimer lamp power supply.

2. The method of claim 1, wherein the method further comprises: The calculation method of the instantaneous dynamic resistance of the lamp tube and the weighted average value of the equivalent impedance within the 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 the preset time window, the equivalent impedance value is obtained by calculating the ratio of the effective values of the lamp tube voltage and the lamp tube current, and the weighted average value of the equivalent impedance is obtained by performing exponential weighted moving average on the continuous equivalent impedance values within the preset time window.

3. The method of claim 2, wherein the method further comprises: The method for correcting the current reference value by using the lamp tube aging characteristic factor to generate the hysteresis comparison current reference center line comprises: 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 method of claim 3, wherein the method further comprises: when the instantaneous dynamic resistance and / or the weighted average value of the equivalent impedance do not accurately correspond to the two-dimensional lookup table index value, in the lamp tube aging two-dimensional lookup table, the adjacent row interval where the instantaneous dynamic resistance is located and the adjacent column interval where the weighted average value of the equivalent impedance is located are found respectively, four closest known data points in the table are determined, the aging characteristic factor corresponding to the current first input and second input is calculated by using a bilinear interpolation algorithm based on the aging characteristic factors of the four known data points.

5. The method of claim 3, wherein the method further comprises: determining whether the lamp is in a standby mode; and if the lamp is in the standby mode, controlling the lamp to operate in the standby mode. The method for performing frequency domain analysis on the lamp tube current ripple within the sliding window to obtain amplitudes and frequencies of main harmonic components within a preset frequency band, and calculating a dynamic bandwidth of hysteresis control by using a preset multivariate function comprises: performing fast Fourier transform on the lamp tube current sampling data within the sliding window to obtain a frequency spectrum of the current ripple; searching for a main harmonic component in a spectrum within a preset frequency band of 20 kHz to 100 kHz, obtaining an amplitude of the main harmonic component with the frequency ; will be described below. with substituted into the preset function calculating the dynamic bandwidth, wherein, is the base bandwidth, is the dimensionless gain coefficient; is the frequency response coefficient, unit: current / frequency; is the reference frequency.

6. The method of claim 4, wherein the method further comprises: The processing process of the target values of the current reference center line and the dynamic bandwidth from the target values before the switching to the target values after the switching comprises: According to the source mode before switching and the target mode after switching, a transition time is determined from a preset mode switching three-dimensional lookup table ; A third order Bezier curve is set, the start point of which is set to the parameter value before switching, the end point is set to the target value after switching, and the two control points and are set to be the same as and respectively. In Time, time variable Linearly increases from 0 to 1, through the Bezier curve formula , the instantaneous target value of the current reference center line and dynamic bandwidth is calculated.

7. The control method of a multi-mode germicidal excimer lamp according to claim 6, characterized in that, If the aging characteristic factor is obtained by the bilinear interpolation algorithm and the corresponding transition time cannot be found in the mode switching three-dimensional lookup table, then the two groups of indexes closest to the aging characteristic factor obtained by the bilinear interpolation algorithm are found in the mode switching three-dimensional lookup table, and the bilinear interpolation algorithm is used again to calculate the final transition time.

8. The method of claim 5, wherein the method further comprises: determining whether the lamp is in a standby mode; and if the lamp is in the standby mode, then controlling the lamp to operate in the standby mode. The calculation method of the upper threshold and the lower threshold of the hysteresis comparison is respectively: upper threshold value ; lower threshold value .

9. The method of claim 8, wherein the method further comprises: The generation process of the control signal of the main switch tube of the driving excimer lamp power supply is: If the current main switch tube is in the on state and the real-time sampling value of the lamp tube current is greater than or equal to the upper threshold, the main switch tube is turned off; If the current main switch tube is in the off state and the real-time sampling value of the lamp tube current is less than or equal to the lower threshold, the main switch tube is turned on.

10. A control system for a multi-mode germicidal excimer lamp, characterized by, The control method comprises a processor and a memory, the memory stores a computer program, and the processor executes the computer program to implement the control method of the multi-mode sterilization excimer lamp according to any one of claims 1-9.

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