Temperature control method and system for multi-environment VCSEL laser

Abstract

The invention relates to the technical field of laser temperature control, in particular to a temperature control method and system for a multi-environment VCSEL laser, and the method comprises the steps: collecting the temperature of the VCSEL laser at each moment, and the current of a thermoelectric refrigerating unit used for carrying out the temperature control of the VCSEL laser at each moment; determining the temperature fast adjustment intensity and the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment; obtaining a steady state adjustment value of the VCSEL at each temperature control moment; determining the magnetic field interference suppression intensity of the VCSEL laser at each temperature control moment; and correcting a first threshold value and a second threshold value of the integral separation PID control algorithm, determining a switching coefficient of an integral item in the integral separation PID control algorithm, and performing temperature control on the VCSEL at each temperature control moment. Therefore, the temperature control precision of the VCSEL laser is improved.

Description

Technical Field

[0001] The present application relates to the technical field of laser temperature control, and in particular to a temperature control method and system for a multi-environment VCSEL laser. Background Art

[0002] Vertical-Cavity Surface-Emitting Lasers (VCSELs) emit laser light from the top surface of integrated circuits. They feature minimal temperature drift in the lasing wavelength, low threshold voltage, and compact packaging. They are primarily used in fields such as fiber-optic communications and optical sensing, and are key components in miniaturized atomic magnetometers. To ensure stable laser output at the target wavelength during operation, precise temperature control methods are required to minimize the impact of environmental fluctuations on the VCSEL. Currently, temperature control of semiconductor lasers is achieved through the collaborative work of hardware circuits and software algorithms, typically using thermoelectric coolers (TECs) to control the temperature of VCSEL lasers.

[0003] The integral separation PID control algorithm can weaken or eliminate the PID integral effect when the VCSEL laser temperature difference is large, thereby improving the VCSEL laser temperature control response speed. When the VCSEL laser temperature difference is small, the integral link is added in a timely manner to eliminate the static error of the VCSEL laser temperature control and improve the temperature control accuracy and stability. The integral separation PID control of the VCSEL laser often uses a fixed threshold and has poor disturbance suppression ability. The VCSEL laser has thermal inertia. When the VCSEL laser temperature deviation is unstable, the integral term will repeatedly turn on and off, resulting in low temperature control accuracy and stability of the VCSEL laser. Summary of the Invention

[0004] In order to solve the above technical problems, the purpose of this application is to provide a temperature control method and system for a multi-environment VCSEL laser. The technical solutions adopted are as follows: In a first aspect, an embodiment of the present application provides a temperature control method for a multi-environment VCSEL laser, the method comprising the following steps: Collect the temperature of the VCSEL laser at each moment, and the current of the thermoelectric cooler used to control the temperature of the VCSEL laser at each moment; Preset each temperature control moment, analyze the change trend of the temperature trend item at each moment in a preset time period before each temperature control moment, and determine the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment based on the difference between the temperatures at the beginning and end of the preset time period; The duration of the preset time period before each temperature control moment is evenly divided into local time periods; the temperature extremes and the proportion of extreme points in each local time period, as well as the degree of dispersion of the extremes in all local time periods corresponding to each temperature control moment, are analyzed to determine the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment; Determine the steady-state adjustment value of the VCSEL laser at each temperature control moment by combining the temperature rapid adjustment intensity and the temperature oscillation characteristic value; Determine the magnetic field interference suppression strength of the VCSEL laser at each temperature control moment by the degree of the current mutation in the preset time period before each temperature control moment and the frequency of occurrence of positive and negative currents at adjacent moments; Combined with the steady-state adjustment value and the magnetic field interference suppression strength, the first threshold and the second threshold of the integral separation PID control algorithm are modified, the switching coefficient of the integral term in the integral separation PID control algorithm is determined, and the integral separation PID control algorithm is used to control the temperature of the VCSEL laser at each temperature control time.

[0005] In one embodiment, determining the intensity of the rapid temperature adjustment includes: The temperatures at all moments within a preset time period before each temperature control moment are combined into a laser temperature sequence, and the laser temperature sequence is evenly divided into subsequences; Determine the difference in temperature mean between the first subsequence and the last subsequence of the laser temperature sequence, estimate the slope of the trend item sequence of the laser temperature sequence, and obtain the slope of the trend item sequence; The temperature rapid adjustment intensity is positively correlated with the difference and negatively correlated with the slope.

[0006] In one embodiment, the slope is used as the exponent of an exponential function with a natural constant as the base, and the product of the calculated result of the exponential function and the difference is used as the temperature rapid modulation intensity of the VCSEL laser at each temperature control moment.

[0007] In one embodiment, determining the temperature oscillation characteristic value includes: Calculate the product of the temperature range and the proportion of extreme points in each local time period, and calculate the cumulative sum of the multiplication results of all local time periods corresponding to each temperature control moment; The temperature oscillation characteristic value is proportional to the cumulative sum and inversely proportional to the discrete degree.

[0008] In one embodiment, determining the steady-state adjustment value includes: The sum of the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment and a preset value greater than 0 is calculated, and the steady-state adjustment value is the normalized value of the ratio of the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment to the sum.

[0009] In one embodiment, determining the magnetic field interference suppression strength includes: Perform mutation point detection on the current at all times in the preset time period before each temperature control moment, and calculate the cumulative value of the mutation probability of the current at all times in the preset time period before each temperature control moment; The proportion of current pairs with opposite current signs among all current pairs at adjacent moments in a preset time period before each temperature control moment is counted, and a normalized value of the product of the accumulated value and the proportion is used as the magnetic field interference suppression intensity of the VCSEL laser at each temperature control moment.

[0010] In one embodiment, the first threshold and the second threshold of the modified integral separation PID control algorithm include: Calculate the product of the magnetic field interference suppression intensity of the VCSEL laser and the steady-state adjustment value at each temperature control moment as the expansion coefficient of the VCSEL laser temperature control integral threshold; For each temperature control moment, the sum of the expansion coefficient and the natural number 1 is calculated, the product of the sum and the first threshold is used as the first threshold correction value, and the product of the sum and the second threshold is used as the second threshold correction value, wherein the first threshold is greater than the second threshold.

[0011] In one embodiment, determining the switching coefficient of the integral term in the integral separation PID control algorithm includes: The difference between the temperature average in the local time period before each temperature control moment and the preset target temperature is calculated as the expected temperature difference value at each temperature control moment, and the switching coefficient is determined based on the numerical relationship between the expected temperature difference value and the first threshold correction value and the second threshold correction value.

[0012] In one embodiment, the switching coefficient is calculated as follows: Where, is the switching coefficient of the integral term in the integral separation PID control algorithm at each temperature control moment, is the expected temperature difference at each temperature control moment, is the first threshold correction value at each temperature control moment, is the second threshold correction value at each temperature control moment, is the preset integral transition coefficient, where .

[0013] In a second aspect, an embodiment of the present application further provides a temperature control system for a multi-environment VCSEL laser, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0014] This application has at least the following beneficial effects: By analyzing the trend change and fast adjustment intensity of the VCSEL laser temperature, this application can more accurately judge the speed of temperature change, thereby adjusting the temperature control strategy in time and significantly improving the response speed of temperature regulation; secondly, through a comprehensive analysis of the temperature extreme difference, the proportion of extreme points and the oscillation characteristics, it is helpful to accurately identify the temperature oscillation state, and then adjust the control parameters, enhance the ability to suppress temperature fluctuations, and ensure that the laser operating temperature is more stable; further, by analyzing the degree of current mutation and the frequency of positive and negative current, it is possible to accurately judge the intensity of magnetic field interference, enhance the ability to identify and suppress magnetic field interference, and avoid temperature control failure or deviation; combined with the steady-state adjustment value and the magnetic field interference suppression intensity, the threshold of the integral separation PID control algorithm is dynamically corrected, and the VCSEL laser is automatically controlled. Canceling the integral effect when the temperature difference of the SEL laser is large can improve the temperature control response speed and avoid excessive overshoot caused by the accumulation of short-time integral links. Especially when the ambient temperature of the VCSEL laser suddenly changes or starts to heat up, the temperature can be adjusted quickly to make it close to the target temperature as soon as possible, thereby improving environmental adaptability. Introducing the integral link when the temperature difference is small can eliminate steady-state errors. At the same time, by adaptively correcting the integral threshold and adjusting the switching coefficient, the steady-state errors caused by algorithm deviation and environmental interference can be eliminated in time, and temperature oscillations can be greatly suppressed, so that the actual temperature of the VCSEL laser is closer to the target temperature, enhancing the temperature control accuracy and stability, and improving the adaptability and robustness of the integral separation PID control algorithm under different environments and interference conditions, thereby improving the temperature control accuracy and stability of the VCSEL laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0016] Figure 1 A flowchart of a temperature control method for a multi-environment VCSEL laser according to an embodiment of the present application; Figure 2 This is the flow chart of adaptive correction of integral threshold. DETAILED DESCRIPTION

[0017] To further illustrate the technical means and effectiveness of this application to achieve the intended invention objectives, the following, in conjunction with the accompanying drawings and preferred embodiments, describes in detail a temperature control method and system for a multi-environment VCSEL laser according to this application, including its specific implementation, structure, features, and effectiveness. In the following description, different references to "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0018] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0019] The following describes in detail a temperature control method and system for a multi-environment VCSEL laser provided by the present application with reference to the accompanying drawings.

[0020] See also Figure 1 , which shows a flowchart of a temperature control method for a multi-environment VCSEL laser provided by an embodiment of the present application, the method comprising the following steps: S1, collecting the temperature of the VCSEL laser at each moment and the current of the thermoelectric cooler used to control the temperature of the VCSEL laser at each moment.

[0021] Since collecting the real-time temperature of the VCSEL laser is a key step to ensure accurate temperature control of the VCSEL laser, in this embodiment, a negative temperature coefficient thermistor NTC10K is placed on the lower surface of the VCSEL laser. The resistance of the NTC10K decreases as the temperature increases. The calculation formula of the negative temperature coefficient thermistor NTC10K is: Where, is the material constant, which is 3950 in this embodiment. is the resistance value at temperature T, It is temperature The resistance value is 10KΩ in this embodiment. The temperature in this embodiment is 25°C.

[0022] Using the NTC10K thermistor placed on the lower surface of the VCSEL laser, the voltage signal fed back by the NTC10K thermistor is continuously collected to obtain the temperature value of the VCSEL laser at each moment.

[0023] The MAX1978 chip connects to the positive and negative terminals of the thermoelectric cooler (TEC) via its CS and OS2 pins, respectively. This chip monitors the current flowing through the TEC in real time and adjusts the current flow and direction. The current direction determines whether the TEC operates in cooling or heating mode. The thermoelectric cooler (TEC) is used to control the temperature of the VCSEL laser.

[0024] In this embodiment, the current and the temperature are collected synchronously, and the collection frequency is set to 200 Hz. The implementer can set it according to actual conditions, and this embodiment does not impose any restrictions on this.

[0025] S2, preset each temperature control moment, analyze the change trend of the temperature trend item at each moment in the preset time period before each temperature control moment, and determine the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment based on the difference in the temperature at the beginning and end of the preset time period.

[0026] In this embodiment, a temperature control moment is set every 0.1 seconds, meaning the VCSEL laser temperature is controlled every 0.1 seconds. For each temperature control moment, the VCSEL laser temperature at all moments in the preset time period preceding the temperature control moment is sequentially organized into a laser temperature sequence, and the TEC current at all moments in the preset time period preceding the temperature control moment is sequentially organized into a TEC drive current sequence. In this embodiment, the preset time period is 2 seconds long. The implementer can customize the temperature control moment interval and the length of the preset time period based on actual circumstances, and this embodiment does not impose any restrictions on this.

[0027] The temperature control of the VCSEL laser can be divided into a fast adjustment stage and a smoothing stage. When the temperature of the VCSEL laser deviates greatly from the target temperature, the temperature control of the VCSEL laser belongs to the fast adjustment stage, and it is necessary to quickly cool or heat the VCSEL laser through the TEC to adjust the temperature of the VCSEL laser significantly in a short period of time. The temperature of the VCSEL laser has a strong trend. When the temperature of the VCSEL laser deviates less from the target temperature, the temperature control of the VCSEL laser belongs to the smoothing stage, and cooling or heating is performed through the TEC to make the actual temperature of the VCSEL laser closer to the target temperature, thereby improving the accuracy of temperature control, and the trend of the VCSEL laser temperature is slightly weaker. This embodiment sets the target temperature of the VCSEL laser to 80°C. The implementer can set it according to the actual situation. This embodiment does not impose any restrictions on this.

[0028] Taking any temperature control moment as an example, the corresponding laser temperature sequence is obtained and used as input for the Seasonal and Trend Decomposition using Loess (STL) algorithm. The trend items of each element in the laser temperature sequence are then assembled into a trend item sequence, arranged in the order of the elements in the laser temperature sequence. This sequence is then recorded as the trend item sequence of the laser temperature sequence. This sequence is used to eliminate acquisition errors and noise interference and characterize the long-term variation characteristics of the laser temperature sequence. The trend item sequence of the laser temperature sequence is used as input for the Sen slope estimation algorithm to obtain the slope of the trend item sequence.

[0029] In addition, the laser temperature sequence is divided into S temperature subsequences, and the S temperature subsequences are numbered in ascending order from sequence number 1 to S according to the arrangement order of the temperature subsequences in the laser temperature sequence. The mean of all data elements in the temperature subsequence of any sequence number is calculated respectively and recorded as the short-term temperature mean. In this embodiment, the value of S is the ratio of the duration of the preset time period to the duration of the interval between two adjacent temperature control moments. The implementer can set it according to actual conditions, and this embodiment does not impose any restrictions on this.

[0030] Calculate the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment , the specific expression is: Where, They are the short-term temperature averages of the temperature subsequences corresponding to sequence numbers 1 and S at each temperature control moment, is the slope of the trend term sequence of the laser temperature sequence at each temperature control moment, and exp() is an exponential function with the natural constant e as the base. It reflects the temperature difference between the beginning and the end of the preset time period. It should be noted that the difference represents the degree of difference between the two variables. Specifically, it can be calculated by the absolute value of the difference, the square of the difference, the ratio, etc. This embodiment does not limit this.

[0031] It should be understood that Used to reflect the laser temperature adjustment value of the VCSEL laser within the preset time period before the temperature control moment. The larger the value is, the greater the amplitude of the VCSEL laser's decrease or increase in a short period of time. It is used to reflect the temperature adjustment trend of the VCSEL laser in the preset time period before the temperature control moment. The larger the value is, the faster the temperature rise or fall rate of the VCSEL laser is, and the more it conforms to the fast adjustment stage of the VCSEL laser temperature control. Therefore, the temperature fast adjustment intensity The bigger.

[0032] S3, dividing the duration of the preset time period before each temperature control moment into local time periods; analyzing the temperature extremes and the proportion of extreme points in each local time period, as well as the degree of dispersion of the extremes in all local time periods corresponding to each temperature control moment, to determine the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment.

[0033] Due to factors such as TEC thermal inertia, nonlinearity, and the coupling of environmental interference, the actual sequential temperature curve during VCSEL laser temperature control exhibits non-smooth characteristics and exhibits oscillatory characteristics. During the fast-adjustment phase, the focus of VCSEL laser temperature control is to quickly approach the target temperature. With rapid temperature increases or decreases, the oscillation characteristics are less pronounced. During the smoothing phase, VCSEL laser temperature control is prone to steady-state errors, with significant oscillation characteristics.

[0034] For each temperature control moment, this embodiment calculates the temperature extremes for all data elements in any temperature subsequence. The laser temperature sequence is used as input to the AMPD (Automatic Multiscale-Based Peak Detection) algorithm to obtain all extreme points in the laser temperature sequence. The ratio of the number of extreme points in each temperature subsequence to the length of the temperature subsequence is calculated, denoted as the extreme point ratio. This is the ratio of the number of extreme points in each temperature subsequence to the total element data in the temperature subsequence. The overall acquisition duration corresponding to all elements in each temperature subsequence is considered a local time period.

[0035] Calculate the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment , the specific expression is: Where, is the ratio of the number of extreme points of the temperature subsequence with sequence number i at each temperature control moment, is the temperature range difference of the temperature subsequence with sequence number i at each temperature control moment, is the degree of discreteness of the temperature extremes of all temperature subsequences in the laser temperature sequence at each temperature control moment, S is the total number of temperature subsequences at each temperature control moment, It is a preset parameter adjustment factor, which is used to avoid the denominator being 0. The value is 0.01, and the implementer can set it according to the actual situation. This embodiment does not limit this. It should be noted that the degree of dispersion can be calculated by using variance, standard deviation, coefficient of variation, etc. This embodiment uses standard deviation as the calculation method for the degree of dispersion.

[0036] It should be understood that in the calculation method of the temperature oscillation characteristic value P, Used to reflect the oscillation amplitude of the temperature subsequence, It is used to evaluate the frequency of temperature fluctuations. The more reliable the oscillation characteristics of frequent fluctuations are, the greater the oscillation weight should be given. The purpose of is to reflect the short-term stability of the laser temperature. The smaller it is, the higher the amplitude consistency of the laser temperature oscillation is, and the more likely it is an oscillation phenomenon occurring in the temperature control smoothing stage, eliminating the impact of significant temperature change trends on the evaluation of temperature oscillation characteristics.

[0037] S4, combining the temperature rapid adjustment intensity and the temperature oscillation characteristic value to determine the steady-state adjustment value of the VCSEL laser at each temperature control moment.

[0038] This embodiment adopts an integral-separated PID temperature control method. When the VCSEL laser temperature control is in the fast adjustment stage, the integral effect is eliminated, so that the TEC temperature control has a faster response speed. When the VCSEL laser temperature control is in the smooth stage, due to the significant oscillation characteristics of the time-series temperature curve change, it is necessary to appropriately add an integral link to eliminate steady-state errors, reduce the laser temperature oscillation amplitude, and improve the accuracy and stability of the VCSEL laser temperature control.

[0039] Specifically, calculate the steady-state adjustment value of the VCSEL laser at each temperature control moment , the specific expression is: Where, is the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment, is the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment, b is a preset parameter adjustment factor, the purpose of which is to avoid the denominator being 0. In this embodiment, b is set to 0.01. The implementer can set it according to the actual situation. This embodiment does not impose any restrictions on this. Norm() is a normalization function.

[0040] It should be understood that Used to reflect the possibility that the VCSEL laser is in the stage of rapid temperature adjustment. The smaller it is, the less likely the VCSEL laser is rapidly heating up or cooling down. The larger the value is, the more significant the oscillation characteristics are in the temporal temperature curve of the VCSEL laser, and the consistency of the oscillation amplitude is high. The higher the possibility that the VCSEL laser is in a steady state, the more likely it is that the VCSEL laser is in a steady state. In the PID temperature control method using integral separation, the more the integral effect should be introduced or strengthened to adjust the steady-state error of the VCSEL laser. The steady-state adjustment value The bigger.

[0041] S5, determining the magnetic field interference suppression intensity of the VCSEL laser at each temperature control moment by the degree of the current mutation at each temperature control moment and in a preset time period before that, and the frequency of occurrence of positive and negative currents at adjacent moments.

[0042] VCSEL lasers are mainly used in atomic magnetometer systems. The method of atomic magnetometer to detect magnetic fields is to measure the 87 The frequency of Larmor precession of Rb atoms in the Earth's magnetic field is controlled by the TEC, which uses a bidirectional DC current to achieve cooling or heating. When the TEC driving current changes suddenly and switches direction frequently, transient magnetic field pulses can easily occur, affecting the proper functioning of the atomic magnetometer. To mitigate magnetic field interference, the integral action of the integral-separated PID temperature control method should be introduced and strengthened as early as possible during the smoothing phase of VCSEL laser temperature control to avoid drastic temperature adjustments.

[0043] In this embodiment, a TEC drive current sequence of the VCSEL laser is obtained at each temperature control moment. The currents at all adjacent moments in the TEC drive current sequence are recorded as a current pair. Assuming that the number of currents in the TEC drive current sequence is N, N-1 current pairs can be obtained. For example, if the TEC drive current sequence is [1, 2, 3, 4], then 1 and 2 form a current pair, 2 and 3 form a current pair, and 3 and 4 form a current pair.

[0044] Secondly, for each current pair in the TEC drive current sequence, if the positive and negative signs of the two current values ​​in the current pair are opposite, the current pair is recorded as a reverse current pair. The proportion of reverse current pairs in all current pairs in the TEC drive current sequence is counted as the zero-crossing rate of the TEC drive current sequence. The TEC driving current sequence is used as the input of the Bayesian online mutation point detection algorithm to obtain the mutation probability of each current value in the TEC driving current sequence.

[0045] Calculate the magnetic field interference suppression intensity of the VCSEL laser at each temperature control moment , the specific expression is: Where, is the mutation probability of the jth current value in the TEC driving current sequence at each temperature control moment, J is the total number of current values ​​in the TEC driving current sequence at each temperature control moment, is the zero-crossing rate of the TEC driving current sequence at each temperature control moment, and Norm() is the normalization function.

[0046] It should be understood that Used to reflect the sudden change of VCSEL laser TEC driving current. It is used to reflect the frequency of switching direction of the VCSEL laser TEC drive current. The greater the mutation of the TEC drive current and the more frequent the direction switching, the more likely it is to generate magnetic field interference, affecting the normal operation of the atomic magnetometer. Therefore, the VCSEL laser temperature control needs to consider the magnetic field interference of the TEC drive current more, and a higher suppression strength is required. The bigger.

[0047] S6, combining the steady-state adjustment value and the magnetic field interference suppression strength, correcting the first threshold and the second threshold of the integral separation PID control algorithm, determining the switching coefficient of the integral term in the integral separation PID control algorithm, and using the integral separation PID control algorithm to control the temperature of the VCSEL laser at each temperature control time.

[0048] For each temperature control moment, this embodiment calculates the difference between the short-term temperature mean of the temperature subsequence numbered S and the target temperature as the expected temperature difference e(k) at each temperature control moment, and sets the first threshold value based on the integral separation PID control algorithm. and the second threshold ,in, .like Greater than or equal to the first threshold , cancel the integral link and improve the response speed of VCSEL laser temperature control. Less than the first threshold and greater than the second threshold , introducing the incomplete integral action, Less than or equal to the second threshold , the integral action is fully introduced, which is equivalent to the temperature PID control of the VCSEL laser and eliminates the steady-state oscillation error.

[0049] Secondly, the steady-state adjustment value of the VCSEL laser The larger the value, the lower the possibility that the VCSEL laser temperature control is in the fast adjustment stage, the more significant the steady-state oscillation characteristics, and the larger the temperature difference between the steady-state oscillation temperature and the target temperature. The first threshold should be increased. and the second threshold , timely introduce and strengthen the integral effect, eliminate the steady-state oscillation phenomenon, and improve the accuracy and stability of VCSEL laser temperature control.

[0050] Based on the above analysis, the expansion coefficient of the VCSEL laser temperature control integral threshold at each temperature control moment is obtained through the steady-state adjustment value and magnetic field interference suppression strength of the VCSEL laser at each temperature control moment. This is used to timely introduce and strengthen the integral effect, eliminate the steady-state oscillation phenomenon, avoid large-scale temperature control, suppress the magnetic field interference of the TEC drive current on the atomic magnetometer, and improve the accuracy and stability of the VCSEL laser temperature control. Specifically, the product of the steady-state adjustment value of the VCSEL laser at each temperature control moment and the magnetic field interference suppression strength is calculated as the expansion coefficient of the VCSEL laser temperature control integral threshold at each temperature control moment. .

[0051] Furthermore, for each temperature control moment, according to the first threshold and the second threshold , and the expansion factor of the integration threshold , through the formula , , obtain the first threshold correction value of VCSEL laser temperature control and the second threshold correction value , adaptively modify the integral threshold. Among them, the first threshold In this embodiment, the second threshold is set to 0.5°C. It is set to 0.01℃, and the implementer can set it according to the actual situation. In order to avoid the VCSEL laser from adjusting the first threshold and the second threshold too frequently, this embodiment sets the first threshold and the second threshold to be adaptively corrected every S temperature control moments. The flow chart of the adaptive correction of the integral threshold is as follows: Figure 2 shown.

[0052] Obtain the switching coefficient of the integral term in the VCSEL laser integral separation PID control algorithm , the target temperature value and the expected temperature difference value e(k) are used as the input of the integral separation PID control algorithm to control the temperature of the VCSEL laser, specifically: Where, is the switching coefficient of the integral term in the integral separation PID control algorithm at each temperature control moment, is the expected temperature difference at each temperature control moment, is the first threshold correction value at each temperature control moment, is the second threshold correction value at each temperature control moment, is the preset integral transition coefficient, where In this embodiment Among them, the integral separation PID control algorithm is a well-known technology, and the specific process is not described in detail.

[0053] When the ambient temperature of the VCSEL laser changes suddenly or starts to rise, canceling the integration link can improve the response speed of the VCSEL laser temperature control and avoid the continuous accumulation of short-time integration links, which may cause excessive overshoot of the VCSEL laser. When the VCSEL laser temperature gradually approaches the target temperature, the adaptive integration threshold is used to promptly eliminate the steady-state error caused by large model deviation and environmental interference in the steady-state oscillation phenomenon of the VCSEL laser. At the same time, it suppresses the TEC drive current with large mutations and frequent direction switching, minimizes the magnetic field interference of the TEC cooling or heating on the atomic magnetometer, and improves the accuracy and stability of the VCSEL laser temperature control.

[0054] Based on the same inventive concept as the above method, an embodiment of the present application further provides a temperature control system for a multi-environment VCSEL laser, comprising a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the steps of any one of the above-mentioned temperature control methods for a multi-environment VCSEL laser are implemented.

[0055] It should be noted that the order in which the embodiments of the present application are presented is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. Furthermore, the foregoing descriptions of specific embodiments of this specification are provided. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential sequence shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0056] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0057] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A temperature control method for a multi-environment VCSEL laser, characterized in that: The method comprises the following steps: Collect the temperature of the VCSEL laser at each moment, and the current of the thermoelectric cooler used to control the temperature of the VCSEL laser at each moment; Preset each temperature control moment, analyze the change trend of the temperature trend item at each moment in a preset time period before each temperature control moment, and determine the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment based on the difference between the temperatures at the beginning and end of the preset time period; The duration of the preset time period before each temperature control moment is evenly divided into local time periods; the temperature extremes and the proportion of extreme points in each local time period, as well as the degree of dispersion of the extremes in all local time periods corresponding to each temperature control moment, are analyzed to determine the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment; Determine the steady-state adjustment value of the VCSEL laser at each temperature control moment by combining the temperature rapid adjustment intensity and the temperature oscillation characteristic value; Determine the magnetic field interference suppression strength of the VCSEL laser at each temperature control moment by the degree of the current mutation in the preset time period before each temperature control moment and the frequency of occurrence of positive and negative currents at adjacent moments; Combined with the steady-state adjustment value and the magnetic field interference suppression strength, the first threshold and the second threshold of the integral separation PID control algorithm are modified, the switching coefficient of the integral term in the integral separation PID control algorithm is determined, and the integral separation PID control algorithm is used to control the temperature of the VCSEL laser at each temperature control time.

2. The temperature control method of a multi-environment VCSEL laser according to claim 1, characterized in that: Determining the intensity of the rapid temperature adjustment includes: The temperatures at all moments within a preset time period before each temperature control moment are combined into a laser temperature sequence, and the laser temperature sequence is evenly divided into subsequences; Determine the difference in temperature mean between the first subsequence and the last subsequence of the laser temperature sequence, estimate the slope of the trend item sequence of the laser temperature sequence, and obtain the slope of the trend item sequence; The temperature rapid adjustment intensity is positively correlated with the difference and negatively correlated with the slope.

3. The temperature control method of a multi-environment VCSEL laser according to claim 2, characterized in that: The slope is used as the exponent of an exponential function with a natural constant as the base, and the product of the calculated result of the exponential function and the difference is used as the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment.

4. The temperature control method of a multi-environment VCSEL laser according to claim 1, wherein: Determining the temperature oscillation characteristic value includes: Calculate the product of the temperature range and the proportion of extreme points in each local time period, and calculate the cumulative sum of the multiplication results of all local time periods corresponding to each temperature control moment; The temperature oscillation characteristic value is proportional to the cumulative sum and inversely proportional to the discrete degree.

5. The temperature control method of a multi-environment VCSEL laser according to claim 1, wherein: Determination of the steady-state adjustment value includes: The sum of the temperature rapid adjustment intensity of the VCSEL laser at each temperature control moment and a preset value greater than 0 is calculated, and the steady-state adjustment value is the normalized value of the ratio of the temperature oscillation characteristic value of the VCSEL laser at each temperature control moment to the sum.

6. The temperature control method of a multi-environment VCSEL laser according to claim 1, wherein: The determination of the magnetic field interference suppression intensity includes: Perform mutation point detection on the current at all times in the preset time period before each temperature control moment, and calculate the cumulative value of the mutation probability of the current at all times in the preset time period before each temperature control moment; The proportion of current pairs with opposite current signs among all current pairs at adjacent moments in a preset time period before each temperature control moment is counted, and a normalized value of the product of the accumulated value and the proportion is used as the magnetic field interference suppression intensity of the VCSEL laser at each temperature control moment.

7. The temperature control method for a multi-environment VCSEL laser according to claim 1, wherein: The first threshold and the second threshold of the modified integral separation PID control algorithm include: Calculate the product of the magnetic field interference suppression intensity of the VCSEL laser and the steady-state adjustment value at each temperature control moment as the expansion coefficient of the VCSEL laser temperature control integral threshold; For each temperature control moment, the sum of the expansion coefficient and the natural number 1 is calculated, the product of the sum and the first threshold is used as the first threshold correction value, and the product of the sum and the second threshold is used as the second threshold correction value, wherein the first threshold is greater than the second threshold.

8. The temperature control method of a multi-environment VCSEL laser according to claim 1, wherein: Determining the switching coefficient of the integral term in the integral separation PID control algorithm includes: The difference between the temperature average in the local time period before each temperature control moment and the preset target temperature is calculated as the expected temperature difference value at each temperature control moment, and the switching coefficient is determined based on the numerical relationship between the expected temperature difference value and the first threshold correction value and the second threshold correction value.

9. The temperature control method of a multi-environment VCSEL laser according to claim 8, characterized in that: The switching coefficient is calculated as follows: Where, is the switching coefficient of the integral term in the integral separation PID control algorithm at each temperature control moment, is the expected temperature difference at each temperature control moment, is the first threshold correction value at each temperature control moment, is the second threshold correction value at each temperature control moment, is the preset integral transition coefficient, where .

10. A temperature control system for a multi-environment VCSEL laser, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 9 are implemented.

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