Method and device for controlling junction temperature of pumping source chip of laser

Abstract

The invention discloses a junction temperature control method and device for a pumping source chip of a laser, and the method comprises the steps: detecting whether the current junction temperature of a pumping module is abnormal or not; when the current junction temperature of the pumping module is abnormal, the power supply module is controlled to input a measuring current and an initial adjusting current to each pumping source; acquiring an acquired calculation parameter for calculating the actual junction temperature of each pump source, and calculating the actual junction temperature of each pump source in combination with the calculation formula of the actual junction temperature; and for each pump source, based on the actual junction temperature of the pump source, performing closed-loop feedback adjustment on the attribute parameters of the initial adjustment current introduced into the pump source, so that the actual junction temperature of the pump source is maintained in a normal range. Therefore, the junction temperature of the chip can be accurately controlled, the service life of the laser can be prolonged to the maximum extent, and the refrigerating capacity waste and the design redundancy can be reduced.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular to a method and device for controlling the junction temperature of a laser pump source chip. Background Art

[0002] The existing laser pump module water cooling system usually uses a water cooling plate to cool the pump module, and the laser has strict requirements on the chip junction temperature. Because too high or too low temperature will have a serious impact on the chip efficiency, the chip junction temperature is usually kept at the optimal operating temperature of the chip. If the chip junction temperature exceeds the optimal operating temperature, the chip will age rapidly, resulting in a reduction in the chip's service life. If the chip junction temperature is lower than the optimal operating temperature, the chip's light output efficiency will be greatly reduced. The existing laser has no control over the chip junction temperature and cannot directly measure the chip junction temperature. It only performs a high temperature alarm on the pump source side. This passive protection measure cannot maximize the service life of the laser, nor can it maximize the chip efficiency. At the same time, it is easy to cause a huge waste of cooling capacity, forming a redundant design. Summary of the invention

[0003] The present invention provides a method and device for controlling the junction temperature of a laser pump source chip, so as to detect and control the junction temperature of the laser pump source chip and increase the service life of the laser.

[0004] To achieve the above object, the first aspect of the present invention provides a method for controlling the junction temperature of a pump source chip of a laser, wherein the laser includes a pump module, the pump module includes a plurality of pump sources, each pump source includes a plurality of chips, and the junction temperature control method includes:

[0005] Detecting whether the current junction temperature of the pump module is abnormal;

[0006] When the current junction temperature of the pump module is abnormal, the power supply module is controlled to supply a measurement current and an initial adjustment current to each of the pump sources respectively;

[0007] Acquire the collected calculation parameters for calculating the actual junction temperature of each of the pump sources, and calculate the actual junction temperature of each of the pump sources in combination with the calculation formula of the actual junction temperature;

[0008] For each of the pump sources, based on the actual junction temperature of the pump source, closed-loop feedback adjusts the property parameters of the initial adjustment current passed into the pump source so that the actual junction temperature of the pump source is maintained within a normal range, wherein the current output by the power module is a variable current, and the property parameters include one of a peak value, a frequency or a reference value.

[0009] Optionally, based on the actual junction temperature of the pump source, closed-loop feedback adjustment of attribute parameters of the initial adjustment current flowing into the pump source includes:

[0010] When the actual junction temperature is greater than a first preset value, reducing a reference value of an initial adjustment current passed by the pump source;

[0011] When the actual junction temperature is greater than a second preset value and less than or equal to the first preset value, reducing a peak value or a frequency of an initial adjustment current passed by the pump source;

[0012] When the actual junction temperature is greater than a third preset value and less than or equal to the second preset value, increasing the peak value or frequency of the initial adjustment current passed by the pump source;

[0013] When the actual junction temperature is less than or equal to the three preset values, increasing the reference value of the initial adjustment current passed by the pump source;

[0014] The third preset value is smaller than the second preset value, and the second preset value is smaller than the first preset value.

[0015] Optionally, acquiring the collected calculation parameters for calculating the actual junction temperature of each of the pump sources, and combining the calculation formula of the actual junction temperature to calculate the actual junction temperature of each of the pump sources includes:

[0016] Obtain the first wavelength of each pump source under the measurement current, the second wavelength under the initial adjustment current, and the collected water inlet temperature of the water cooling plate where the pump module is located, based on T 实际结温 =(λ 2 -λ 1 ) / δ+T 入水 The actual junction temperature of each pump source is calculated by the formula, where λ 1 is the first wavelength, λ 2 is the second wavelength, T 入水 is the water inlet temperature of the water cooling plate, δ is the temperature drift coefficient of the pump source chip, and the difference between the initial adjustment current and the measurement current is greater than or equal to a fourth preset value.

[0017] Optionally, the fourth preset value is 12A.

[0018] Optionally, calculating the actual junction temperature of the laser pump source chip based on the difference between the first wavelength and the second wavelength, the water inlet temperature of the water cooling plate, and the pump source chip temperature drift coefficient includes:

[0019] Based on T 实际结温 =(λ 2 -λ 1 ) / δ+T 入水 Calculate the actual junction temperature, λ 1 is the first wavelength, λ 2 is the second wavelength, T 入水 is the water inlet temperature of the water cooling plate, and δ is the temperature drift coefficient of the pump source chip.

[0020] Optionally, detecting whether the current junction temperature of the pump module is abnormal includes:

[0021] Obtaining the water inlet temperature and the water outlet temperature of the water cooling plate where the pump module is located, and calculating the current inlet and outlet water temperature difference of the water cooling plate;

[0022] Obtaining a theoretical temperature difference of the temperature change of the water cooling plate caused by the total amount of heat generated by the pump module at the theoretical operating temperature;

[0023] Determine whether the difference between the current inlet and outlet water temperature difference and the theoretical temperature difference is within a preset temperature range; if so, determine that the current junction temperature of the pump module is normal; if not, determine that the current junction temperature of the pump module is abnormal.

[0024] Optionally, the preset temperature range is -0.1°C to +0.1°C.

[0025] Optionally, obtaining a theoretical temperature difference of the temperature change of the water cooling plate caused by the total amount of heat generated by the pump module at the theoretical operating temperature includes:

[0026] Obtaining the theoretical light output power and conversion efficiency of the pump module at the theoretical operating temperature;

[0027] Calculating the total amount of heat generated by the pump module based on the theoretical output light power and conversion efficiency;

[0028] Based on the total amount of heat generated and the specific volume heat formula, a theoretical temperature difference of the temperature change of the water cooling plate is calculated.

[0029] Optionally, based on the actual junction temperature of the pump source, the attribute parameters of the closed-loop feedback adjustment of the initial adjustment current flowing into the pump source include:

[0030] The attribute parameters of the initial adjustment current passed by the pump source are adjusted in steps of decreasing or increasing, wherein during the adjustment process, each adjustment gradient can cause the actual junction temperature of the pump source to change by 0.1° C. to 1° C.

[0031] To achieve the above-mentioned purpose, the second aspect of the present invention provides a laser pump source chip junction temperature control device, which is used to implement the laser pump source chip junction temperature control method described in any embodiment of the present invention, and the junction temperature control device includes:

[0032] A power module, a temperature monitoring device, a wavelength detection device, a current modulator and a controller, wherein the temperature monitoring device is used to detect the water inlet temperature and the water outlet temperature of the water cooling plate where the pump module is located, the current modulator is used to adjust the initial adjustment current passed by the power module to each pump source, and the wavelength detection device is used to detect the light output wavelength of each pump source;

[0033] The controller is connected to the temperature monitoring device, the current modulator, the wavelength detection device and the power module respectively, and the controller is used to execute the laser pump source chip junction temperature control method described in any embodiment of the present invention.

[0034] Optionally, the wavelength detection device includes one of a spectrometer, a wavelength meter or an interferometer; the temperature detection device includes a thermistor sensor or a thermocouple sensor.

[0035] According to the laser pump source chip junction temperature control method and device proposed in the embodiment of the present invention, the laser includes a pump module, the pump module includes multiple pump sources, each pump source includes multiple chips, and the junction temperature control method includes: detecting whether the current junction temperature of the pump module is abnormal; when the current junction temperature of the pump module is abnormal, controlling the power supply module to pass the measurement current and the initial adjustment current to each pump source respectively; obtaining the collected calculation parameters for calculating the actual junction temperature of each pump source, and combining the calculation formula of the actual junction temperature to calculate the actual junction temperature of each pump source; for each pump source, based on the actual junction temperature of the pump source, the closed-loop feedback adjusts the attribute parameters of the initial adjustment current passed into the pump source so that the actual junction temperature of the pump source is maintained within a normal range, wherein the current output by the power supply module is a variable current, and the attribute parameters include one of a peak value, a frequency or a reference value. Therefore, when the junction temperature of the pump module is detected to be abnormal in the application, the attribute parameters of the current passed into it can be adjusted according to the size of the actual junction temperature of each pump source, so that the actual junction temperature of the pump source is controlled within a reasonable range, avoiding pump source failure and extending the service life of the laser. The solution of the present invention is conducive to accurately controlling the junction temperature of the pump source, maximizing the service life of the laser, and reducing the waste of cooling capacity and design redundancy.

[0036] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 is a flow chart of a method for controlling the junction temperature of a laser pump source chip provided in an embodiment of the present invention;

[0039] Figure 2 is a diagram showing the fluctuation of junction temperature with current in the method for controlling junction temperature of a laser pump source chip provided in an embodiment of the present invention;

[0040] Figure 3 It is a flow chart of a method for controlling the junction temperature of a laser pump source chip proposed in a specific embodiment of the present invention;

[0041] Figure 4 It is a block diagram of a laser pump source chip junction temperature control device proposed in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0043] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] Figure 1 It is a flow chart of a method for controlling the junction temperature of a laser pump source chip proposed in an embodiment of the present invention.

[0045] like Figure 1 As shown, the method includes:

[0046] S101, detecting whether the current junction temperature of the pump module is abnormal.

[0047] Among them, the pump module includes multiple pump sources, each pump source includes multiple chips, each chip can emit a light beam after being powered on, the light beams of multiple chips in each pump source can be combined, and the light beams formed by the multiple pump sources in the pump module can be combined again and emitted as a laser beam of the laser.

[0048] Since the actual junction temperature of the pump module is complicated to measure, and the laser cannot be used normally during the measurement. When the laser is used or applied, the junction temperature of the pump module cannot be measured. Furthermore, when the laser is used or applied, the junction temperature of the pump module can be determined by measuring the parameters that can indirectly reflect the junction temperature of the pump module to determine whether it is abnormal. Furthermore, it can be determined whether it is abnormal by the inlet and outlet water temperature difference of the water cooling plate that carries the pump module. That is, during the use of the laser, the corresponding inlet and outlet water temperature difference threshold can be set. When the inlet and outlet water temperature difference exceeds the inlet and outlet water temperature difference threshold, it is considered that the current junction temperature of the pump module is abnormal.

[0049] S102, when the current junction temperature of the pump module is abnormal, the power supply module is controlled to supply a measurement current and an initial adjustment current to each pump source respectively.

[0050] The measured current is the current that the laser pump module can just start working, and the initial adjustment current is generally the current for the normal operation of the laser, or the required current configured by the user for the laser. Generally, the measured current is smaller than the initial adjustment current. The purpose of passing the measured current and the initial adjustment current is to enable the corresponding acquisition equipment to collect the corresponding calculation parameters for calculating the actual junction temperature of each pump source based on the actual junction temperature calculation formula of the pump source.

[0051] S103, obtaining the collected calculation parameters for calculating the actual junction temperature of each pump source, and calculating the actual junction temperature of each pump source in combination with the calculation formula of the actual junction temperature.

[0052] When the current junction temperature of the pump module is abnormal, the laser can be disassembled, and the corresponding current can be passed through each pump source. After obtaining the corresponding actual junction temperature calculation parameters according to the actual junction temperature calculation formula, the actual junction temperature of each pump source in the pump module can be measured based on the calculation formula. The actual junction temperature of each pump source can be understood as the coupling value or average value of the junction temperatures of multiple chips in the pump source. Then, the actual junction temperature value of the pump source can be used to specifically analyze which pump source in the pump module has an abnormal junction temperature so that corresponding corrections can be made.

[0053] S104, for each pump source, based on the actual junction temperature of the pump source, closed-loop feedback adjusts the attribute parameters of the initial adjustment current passed into the pump source to maintain the actual junction temperature of the pump source within a normal range, wherein the current output by the power module is a variable current, and the attribute parameters include one of a peak value, a frequency, or a reference value.

[0054] It is understandable that after measuring the actual junction temperature of the pump source, since each pump source has a junction temperature range in which it can work normally, the light output power of the pump source directly affects the junction temperature, and the light output power of the pump source is directly related to the current, and then the property parameters of the current provided to the pump source can be adjusted to adjust the light output power of the pump source, thereby adjusting the junction temperature of the pump source, that is, through a closed-loop feedback adjustment method, a current value is finally obtained so that the actual junction temperature of the pump source is maintained within the normal working junction temperature range. Then the property parameters of the current of the adjusted pump source are recorded, and when the laser is applied or used again, the corresponding pump source is powered by this current. It should be noted that the adjusted current here and the current used to adjust the current below are both the initial adjustment currents mentioned above, that is, the current generally adjusted is the current for normal operation of the laser.

[0055] The current may be a square wave, a sine wave or a cosine wave, the peak value is the maximum amplitude or the minimum amplitude of the square wave, the sine wave or the cosine wave, the frequency is the frequency of the current, and the reference value is the median of the difference between the maximum amplitude and the minimum amplitude of the sine wave or the cosine wave.

[0056] Therefore, the above method does not need to frequently measure the actual junction temperature of each pump source. The actual junction temperature of the pump source needs to be measured only when it is monitored that the junction temperature of the pump module is abnormal when the laser is in use or applied, thereby reducing the number of measurements and the measurement cost. In addition, the optical power of the pump source is adjusted accordingly by the changing current, so that the junction temperature of each pump source can be maintained within the normal range when the laser is used again, thereby extending the life of the laser.

[0057] Optionally, based on the actual junction temperature of the pump source, closed-loop feedback adjusts the property parameters of the initial adjustment current passed into the pump source, including:

[0058] When the actual junction temperature is greater than the first preset value, reducing the reference value of the initial adjustment current passed by the pump source;

[0059] When the actual junction temperature is greater than the second preset value and less than or equal to the first preset value, reducing the peak value or frequency of the initial adjustment current passed by the pump source;

[0060] When the actual junction temperature is greater than the third preset value and less than or equal to the second preset value, increasing the peak value or frequency of the initial adjustment current passed by the pump source;

[0061] When the actual junction temperature is less than or equal to three preset values, the reference value of the initial adjustment current passed by the pump source is increased;

[0062] The third preset value is smaller than the second preset value, and the second preset value is smaller than the first preset value.

[0063] For example, the normal junction temperature of the pump source of a certain model of laser needs to be stable at 70°C for the best working condition. Then the first preset value may be 71°C, the second preset value may be 70°C, and the third preset value may be 69°C.

[0064] When the actual junction temperature is greater than the first preset value, the reference value of the current provided to the pump source is adjusted to be lowered. That is to say, when the actual junction temperature is greater than 71°C, it means that the temperature is too high. The reference value of the current can be adjusted to reduce the light output power of the pump source, and then reduce the energy of the pump source, so as to reduce the actual junction temperature.

[0065] When the actual junction temperature is greater than the second preset value and less than or equal to the first preset value, the peak value or frequency of the current provided to the pump source is adjusted to be reduced; that is, the actual junction temperature is between 70°C and 71°C, indicating that the temperature is slightly high. The peak value or frequency of the current can be adjusted to reduce the light output power of the pump source, and then reduce the energy of the pump source, thereby reducing the actual junction temperature.

[0066] When the actual junction temperature is greater than the third preset value and less than or equal to the second preset value, the peak value or frequency of the current provided to the pump source is adjusted to increase; that is, the actual junction temperature is between 69°C and 70°C, indicating that the temperature is slightly low. The peak value or frequency of the current can be adjusted to increase the light output power of the pump source, and then, increase the energy of the pump source, thereby increasing the actual junction temperature.

[0067] When the actual junction temperature is less than or equal to three preset values, the reference value of the current provided to the pump source is adjusted to increase. That is to say, when the actual junction temperature is less than 69°C, it means that the temperature is too low. The reference value of the current can be adjusted to increase the light output power of the pump source, and then increase the energy of the pump source, so that the actual junction temperature can be increased.

[0068] It is understandable that the above setting principle of 71℃ and 69℃ is based on the material of the existing chip in the pump source. Under the same heat dissipation conditions, the junction temperature changes by about 1℃ when the current of the existing chip material changes by 1A. When the junction temperature of the pump source is between 69℃ and 71℃, it is difficult to adjust the current reference value accurately, so the current peak value and frequency are adjusted. Figure 2 As shown, Figure 2 The square wave is the current signal curve, and the sine wave is the junction temperature curve. Because the electrical signal changes much faster than the temperature changes, that is, when the current changes, the temperature changes will have a certain delay. Therefore, adjusting the current peak value and frequency can more accurately control the junction temperature change of the pump source.

[0069] Optionally, based on the actual junction temperature of the pump source, the attribute parameters of the closed-loop feedback adjustment of the initial adjustment current passed into the pump source include:

[0070] The attribute parameters of the initial adjustment current passed by the pump source are adjusted in steps of decreasing or increasing. During the adjustment process, each adjustment gradient can cause the actual junction temperature of the pump source to change by 0.1°C to 1°C.

[0071] It should be noted that when adjusting, there is no fixed value for the reduction of the current reference value, which depends on the material properties of the chip of the pump source. If the current reference value of a certain chip changes by 1A, the junction temperature changes by 1°C, then the junction temperature has a regulating effect when it is greater than 71°C and less than 69°C, proving that the current value of 1A is set reasonably. If the current of a certain chip changes by 1A and the junction temperature changes by 2°C, then it will be unable to adjust when it is greater than 71°C and less than 69°C, such as directly cooling from 71°C to 69°C, then 1A is unreasonable. The chips on the market generally have a junction temperature change of about 1°C when the current changes by 1A. 1A is an experimentally measured value, which is determined by the inherent characteristics of the chip. If it has a gradient, it means that the gradient is 1°C for every 1A change. For example, 50A becomes 49A, and the junction temperature exceeds 71°C, then continue with 48A, if it doesn't work, continue with 47A, and so on. The current peak value and frequency are not fixed, and there is no specific value. They can be set according to different companies and different products. The only principle is that this value should be as small as possible, but it cannot be set so small that the junction temperature does not change. Otherwise, there is no point in adjusting. Usually, the value can be set based on a 0.1℃ change in junction temperature. The gradient is the value itself, and the value is changed once each time. Repeat the judgment. In other words, each time the current is adjusted, it can be adjusted with a step amplitude change, and it must be ensured that the junction temperature change is greater than 0.1℃ and less than 1℃ each time the current is adjusted.

[0072] Optionally, obtaining the collected calculation parameters for calculating the actual junction temperature of each pump source, and combining the calculation formula of the actual junction temperature to calculate the actual junction temperature of each pump source includes:

[0073] Obtain the first wavelength of each pump source under the measured current, the second wavelength under the initial adjustment current, and the collected water inlet temperature of the water cooling plate where the pump module is located. Based on T 实际结温 =(λ 2 -λ 1 ) / δ+T 入水 The calculation formula calculates the actual junction temperature of each pump source, where λ 1 is the first wavelength, λ 2 is the second wavelength, T 入水 is the water inlet temperature of the water cooling plate, δ is the temperature drift coefficient of the pump source chip, and the difference between the initial adjustment current and the measured current is greater than or equal to the fourth preset value.

[0074] It should be noted that there needs to be a certain difference between the initial adjustment current and the measured current, so that there is a corresponding difference between the first wavelength and the second wavelength, and the actual junction temperature calculated in the end is meaningful. Among them, the initial adjustment current is generally the current of the laser running at full power, or the current under normal use and normal application, and the measured current is generally the current of the laser running at minimum power. In one embodiment, the initial adjustment current can be 50A and the measured current can be 3A.

[0075] Based on T 实际结温 =(λ 2 -λ 1 ) / δ+T 入水 Calculate the actual junction temperature, λ 1 is the first wavelength, λ 2 is the second wavelength, T 入水 is the water inlet temperature of the water cooling plate, and δ is the temperature drift coefficient of the pump source chip.

[0076] Specifically, when calculating the actual junction temperature, it is necessary to add an optical wavelength detection device at the pump source light output position to record the first wavelength λ at 3A current. 1 and the second wavelength λ when the current is 50A 2 Since the wavelength of the pump light is very sensitive to temperature, it can be calculated by the formula T 实际结温 =(λ 2 -λ 1 ) / δ+T 入水 The actual junction temperature T of the pump source is obtained 实际结温 The chip temperature drift coefficient is a measured value, usually between 0.3 and 0.4, and may fluctuate slightly depending on the material.

[0077] The junction temperature test of the pump source is performed by measuring the wavelength at 3A current and the wavelength at the current (for example, 50A) through T 实际结温 =(λ 2 -λ 1 ) / δ+T 入水 The wavelength of 3A is calculated by the formula and is used as the wavelength reference point. If the current is too low, the pump source will not be able to excite light, and if the current is too high, it will affect the pump source characteristics. Here, 3A is an empirical value. When the current is 50A, the wavelength of the pump source light is the actual wavelength used. 50A is to achieve the designed value of the pump source light output power. Different light output powers have different currents. Here, 50A is just an example. For each pump source, the change in wavelength can sensitively reflect the change in temperature.

[0078] In other embodiments, the initial adjustment current and the measured current can be set accordingly according to the specific situation. Optionally, the difference between the initial adjustment current and the measured current is greater than or equal to a fourth preset value, and the fourth preset value can be 12A. Preferably, the difference between the initial adjustment current and the measured current can satisfy the preset current range of 12A-16A, and preferably, the difference between the two can satisfy 15A.

[0079] Furthermore, after the measurement current is passed to obtain the second wavelength, the initial adjustment current can be passed to obtain the first wavelength, and then the actual junction temperature of the pump source is calculated based on the calculation formula, and the size of the initial adjustment current is adjusted by closed-loop feedback. The current that maintains the actual junction temperature of the pump source at the normal junction temperature is recorded and used in the application, ultimately maintaining the junction temperature of the pump module of the entire laser at a normal level.

[0080] Optionally, detecting whether the current junction temperature of the pump module is abnormal includes:

[0081] Obtain the inlet and outlet water temperatures of the water cooling plate where the pump module is located, and calculate the current inlet and outlet water temperature difference of the water cooling plate;

[0082] Obtain the theoretical temperature difference of the temperature change of the water cooling plate caused by the total amount of heat generated by the pump module at the theoretical working temperature;

[0083] It is determined whether the difference between the current inlet and outlet water temperature difference and the theoretical temperature difference is within a preset temperature range; if so, it is determined that the current junction temperature of the pump module is normal; if not, it is determined that the current junction temperature of the pump module is abnormal.

[0084] Optionally, the preset temperature range is -0.1°C to +0.1°C.

[0085] Optionally, obtaining a theoretical temperature difference of a temperature change of a water cooling plate caused by a total amount of heat generated by the pump module at a theoretical operating temperature includes:

[0086] Obtain the theoretical optical output power and conversion efficiency of the pump module at the theoretical operating temperature;

[0087] Calculate the total heat generated by the pump module based on the theoretical optical output power and conversion efficiency;

[0088] Based on the total heat generation and specific volume heat formula, the theoretical temperature difference of the temperature change of the water cooling plate is calculated.

[0089] It should be noted that a water temperature monitoring device (such as a temperature sensor) is placed at the water inlet and outlet of the laser water cooling plate to monitor the water inlet temperature and water outlet temperature. 入水 and outlet water temperature T 出水 , the inlet and outlet water temperature difference ΔT is obtained 实际 .

[0090] In addition, according to the formula Q = CMΔT 理论 , the ΔT that should be changed when the inlet and outlet water temperature difference is at the optimal operating temperature of the pump module can be calculated 理论 . That is to say, the pump module converts the provided current into light energy. During the conversion, there is a certain conversion efficiency, and it is impossible to convert all the current into light energy. Among them, the electric power of the pump module will be known in advance, and the conversion efficiency will also be known. (The electric power, efficiency and other values ​​are all inherent parameters of the chip, mostly provided by the supplier). Therefore, when the electric power of the pump module is 60W and the conversion efficiency is 63%, the light output power of the pump module is 60W*63%=37.8W. Only 37.8W of the 60W electric power is used for the pump module to emit light, and the remaining energy 60W-37.8W=22.2W is converted into heat in the water cooling plate, which becomes the current invalid energy of the pump module, that is, Q=CMΔT 理论 In the formula, Q and C are the specific heat capacity of water, and M is the mass of water that can be stored in the water cooling plate. From this, ΔT can be calculated. 理论 .

[0091] If there is no other loss or change, ΔT 实际 -ΔT 理论 is within ±0.1℃. This means that the current junction temperature of the laser pump module is normal. 实际 -ΔT 理论 If ΔT is greater than +0.1, the current junction temperature of the laser pump module is too high. 实际 -ΔT 理论 If it is less than -0.1, the laser pump module does not achieve maximum efficiency. 理论 This is the inlet and outlet water temperature difference threshold mentioned in the previous article.

[0092] Therefore, when it is determined that the current junction temperature of the laser pump module is abnormal, the actual junction temperature of each pump source in the laser pump module can be obtained, and the current supplied to each pump source of the laser can be adjusted so that each pump source of the laser can operate within the normal junction temperature range, thereby making the laser operate within the optimal temperature range. In this embodiment, ΔT is allowed 理论 With ΔT 实际 There is a slight error between them, which can avoid frequent measurements of the actual junction temperature of each pump source of the laser.

[0093] In another embodiment, ΔT 实际 -ΔT 理论 =0, the inlet and outlet water temperature difference is exactly the same as the theoretical temperature difference caused by the heating of the pump module.

[0094] That is to say, in the above obtained ΔT 理论 =ΔT 实际Only when the junction temperature of the pump module is normal can it be judged that the current junction temperature of the pump module is normal, otherwise it is abnormal. This condition is relatively strict, but it can well monitor the junction temperature of the pump module and correct the pump module in time.

[0095] Thus, in a specific embodiment, Figure 3 As shown, the laser pump source chip junction temperature control method includes:

[0096] At the beginning, S201, the inlet water temperature and outlet water temperature of the cold water plate are obtained, and the difference ΔT between the inlet water temperature and the outlet water temperature is calculated. 实际 ;

[0097] S202, determining the difference ΔT 实际 With ΔT 理论 Is the difference between the two values ​​within the preset temperature range? If so, return to S201; if not, execute S203;

[0098] S203, calculating the actual junction temperature of each pump source in the laser;

[0099] S204, for one of the pump sources, determining whether the actual junction temperature of the pump source is greater than a first preset value, if so, executing S205, if not, executing S206;

[0100] S205, lower the current reference value, and return to S203;

[0101] S206, determining whether the actual junction temperature of the pump source is greater than a second preset value, if so, executing S207, if not, executing S208;

[0102] S207, lowering and adjusting the current peak value or frequency, and returning to S203;

[0103] S208, determining whether the actual junction temperature of the pump source is greater than a third preset value, if so, executing S209; if not, executing S210;

[0104] S209, increase and adjust the current peak value or frequency, and return to S203;

[0105] S210, increase the current reference value, and return to S203.

[0106] Therefore, the method monitors the water inlet and outlet temperatures of the water cooling plate, and simultaneously passes square wave, sine or cosine current to the pump source, monitors the waveform change value of the pump source outlet current, and simultaneously monitors the change value of the pump source output light wavelength, calculates through formulas, and gives the electric control system control logic to perform current control, thereby achieving the effect of controlling the junction temperature of the pump module. This method can not only reduce the use failure of the laser, greatly increase the service life of the laser, but also maximize the light output efficiency of the laser, reducing the waste of cooling capacity and design redundancy.

[0107] The embodiment of the present invention provides a laser pump source chip junction temperature control device, such as Figure 4 As shown, it includes: a power module 101, a temperature monitoring device 102, a wavelength detection device 103, a current modulator 104 and a controller 105, wherein the temperature monitoring device 102 is used to detect the water inlet temperature and the water outlet temperature of the water cooling plate where the pump module is located, the current modulator 104 is used to adjust the initial adjustment current passed by the power module 101 to each pump source, and the wavelength detection device 103 is used to detect the light output wavelength of each pump source;

[0108] The controller 105 is connected to the temperature monitoring device 102 , the current modulator 104 , the wavelength detection device 103 and the power module 101 respectively, and is used to execute the laser pump source chip junction temperature control method of any embodiment of the present invention.

[0109] Optionally, the wavelength detection device 103 includes one of a spectrometer, a wavelength meter or an interferometer; and the temperature detection device 102 includes a thermistor sensor or a thermocouple sensor.

[0110] Among them, when the temperature monitoring device 102 detects that the current junction temperature of the pump module is abnormal, the laser is turned off, a measurement current of 3A is passed through each pump source in the laser through the power module 101, and the wavelength detection device 103 is used to detect the wavelength of each pump source, and then an initial adjustment current of 50A is passed, and the wavelength detection device 103 is used to detect the wavelength of each pump source, and the actual junction temperature of each pump source is calculated based on the actual junction temperature calculation formula. After calculation, by comparing the actual junction temperature with the normal junction temperature, the initial adjustment current passed into the pump source is modulated by the current modulator 104, so that the actual junction temperature changes to the normal junction temperature. Thereby, a current that can maintain the pump source at a normal junction temperature is found. Then, when the laser is working, the pump module can work at a normal temperature (i.e., the optimal operating temperature). The above process can be controlled and realized by the controller 105.

[0111] It will be appreciated that the apparatus and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0112] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0113] According to the laser pump source chip junction temperature control method and device proposed in the embodiment of the present invention, the laser includes a pump module, the pump module includes multiple pump sources, each pump source includes multiple chips, and the junction temperature control method includes: detecting whether the current junction temperature of the pump module is abnormal; when the current junction temperature of the pump module is abnormal, controlling the power supply module to pass the measurement current and the initial adjustment current to each pump source respectively; obtaining the collected calculation parameters for calculating the actual junction temperature of each pump source, and combining the calculation formula of the actual junction temperature to calculate the actual junction temperature of each pump source; for each pump source, based on the actual junction temperature of the pump source, the closed-loop feedback adjusts the attribute parameters of the initial adjustment current passed into the pump source so that the actual junction temperature of the pump source is maintained within a normal range, wherein the current output by the power supply module is a variable current, and the attribute parameters include one of a peak value, a frequency or a reference value. Therefore, when the junction temperature of the pump module is detected to be abnormal in the application, the attribute parameters of the current passed into it can be adjusted according to the size of the actual junction temperature of each pump source, so that the actual junction temperature of the pump source is controlled within a reasonable range, avoiding pump source failure and extending the service life of the laser. The solution of the present invention is conducive to accurately controlling the junction temperature of the pump source, maximizing the service life of the laser, and reducing the waste of cooling capacity and design redundancy.

[0114] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0115] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for controlling the junction temperature of a laser pump chip, characterized in that: The laser includes a pump module, the pump module includes a plurality of pump sources, each pump source includes a plurality of chips, and the junction temperature control method includes: Detecting whether the current junction temperature of the pump module is abnormal; When the current junction temperature of the pump module is abnormal, the power supply module is controlled to supply a measurement current and an initial adjustment current to each of the pump sources respectively; Acquire the collected calculation parameters for calculating the actual junction temperature of each of the pump sources, and calculate the actual junction temperature of each of the pump sources in combination with the calculation formula of the actual junction temperature; For each of the pump sources, based on the actual junction temperature of the pump source, closed-loop feedback adjusts the property parameters of the initial adjustment current passed into the pump source so that the actual junction temperature of the pump source is maintained within a normal range, wherein the current output by the power module is a variable current, and the property parameters include one of a peak value, a frequency or a reference value.

2. The laser pump source chip junction temperature control method according to claim 1, characterized in that: Based on the actual junction temperature of the pump source, closed-loop feedback adjusts the attribute parameters of the initial adjustment current passed into the pump source, including: When the actual junction temperature is greater than a first preset value, reducing a reference value of an initial adjustment current passed by the pump source; When the actual junction temperature is greater than a second preset value and less than or equal to the first preset value, reducing a peak value or a frequency of an initial adjustment current passed by the pump source; When the actual junction temperature is greater than a third preset value and less than or equal to the second preset value, increasing the peak value or frequency of the initial adjustment current passed by the pump source; When the actual junction temperature is less than or equal to the three preset values, increasing the reference value of the initial adjustment current passed by the pump source; The third preset value is smaller than the second preset value, and the second preset value is smaller than the first preset value.

3. The laser pump source chip junction temperature control method according to claim 1, characterized in that: Acquiring the collected calculation parameters for calculating the actual junction temperature of each of the pump sources, and combining the calculation formula of the actual junction temperature to calculate the actual junction temperature of each of the pump sources includes: Obtain the first wavelength of each pump source under the measurement current, the second wavelength under the initial adjustment current, and the collected water inlet temperature of the water cooling plate where the pump module is located, based on T 实际结温 =(λ2-λ1) / δ+T 入水 The actual junction temperature of each of the pump sources is calculated by the formula, wherein λ1 is the first wavelength, λ2 is the second wavelength, T 入水 is the water inlet temperature of the water cooling plate, δ is the temperature drift coefficient of the pump source chip, and the difference between the initial adjustment current and the measurement current is greater than or equal to a fourth preset value.

4. The laser pump source chip junction temperature control method according to claim 3, characterized in that: The fourth preset value is 12A.

5. The laser pump source chip junction temperature control method according to claim 1, characterized in that: Detecting whether the current junction temperature of the pump module is abnormal includes: Obtaining the water inlet temperature and the water outlet temperature of the water cooling plate where the pump module is located, and calculating the current inlet and outlet water temperature difference of the water cooling plate; Obtaining a theoretical temperature difference of the temperature change of the water cooling plate caused by the total amount of heat generated by the pump module at the theoretical operating temperature; Determine whether the difference between the current inlet and outlet water temperature difference and the theoretical temperature difference is within a preset temperature range; if so, determine that the current junction temperature of the pump module is normal; if not, determine that the current junction temperature of the pump module is abnormal.

6. The laser pump source chip junction temperature control method according to claim 5, characterized in that: The preset temperature range is -0.1°C to +0.1°C.

7. The laser pump source chip junction temperature control method according to claim 5, characterized in that: Obtaining the theoretical temperature difference of the temperature change of the water cooling plate caused by the total amount of heat generated by the pump module at the theoretical operating temperature includes: Obtaining the theoretical light output power and conversion efficiency of the pump module at the theoretical operating temperature; Calculating the total amount of heat generated by the pump module based on the theoretical output light power and conversion efficiency; Based on the total amount of heat generated and the specific volume heat formula, a theoretical temperature difference of the temperature change of the water cooling plate is calculated.

8. The laser pump source chip junction temperature control method according to claim 1, characterized in that: Based on the actual junction temperature of the pump source, the attribute parameters of the closed-loop feedback adjustment of the initial adjustment current passed into the pump source include: The attribute parameters of the initial adjustment current passed by the pump source are adjusted in steps of decreasing or increasing, wherein during the adjustment process, each adjustment gradient can cause the actual junction temperature of the pump source to change by 0.1° C. to 1° C.

9. A laser pump chip junction temperature control device, characterized in that: A method for controlling the junction temperature of a pump source chip of a laser according to any one of claims 1 to 8, wherein the junction temperature control device comprises: A power module, a temperature monitoring device, a wavelength detection device, a current modulator and a controller, wherein the temperature monitoring device is used to detect the water inlet temperature and the water outlet temperature of the water cooling plate where the pump module is located, the current modulator is used to adjust the initial adjustment current passed by the power module to each pump source, and the wavelength detection device is used to detect the light output wavelength of each pump source; The controller is connected to the temperature monitoring device, the current modulator, the wavelength detection device and the power module respectively, and the controller is used to execute the laser pump source chip junction temperature control method as described in any one of claims 1-8.

10. The laser pump chip junction temperature control device according to claim 9, characterized in that: The wavelength detection device includes one of a spectrometer, a wave meter or an interferometer; The temperature detection device includes a thermistor sensor or a thermocouple sensor.

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