Current peak control device and method applied to laser driving power supply

Abstract

The invention relates to the technical field of laser driving power supplies, in particular to a current peak control device and method applied to a laser driving power supply. Comprising a current sampling module, a precision adjusting module, a control comparison module and a power supply master control module. The output current of the laser driving power supply is sampled by using the current sampling module, the duty ratio of each path of PWM is regulated and controlled through the precision regulation module, the output current of the laser driving power supply is subjected to high-precision regulation, and the current reference value is determined; the control comparison module is used for comparing the collected output current of the laser driving power supply with a current reference value determined in the digital signal processor, a current peak signal is regulated and controlled, a driving control signal is output through the power supply main control module, the switch-on and switch-off time of a switch tube is controlled, the current of the laser driving power supply is regulated and controlled, and the laser driving power supply is controlled. Current ripples output by the laser driving power supply are reduced, and the normal working state of the semiconductor laser is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of laser drive power supplies, and more specifically, to a device and method for controlling the current peak applied to a laser drive power supply. Background Art

[0002] A semiconductor laser directly injects current into a semiconductor PN junction to achieve population inversion and generate stimulated radiation. Then, a resonant cavity is used for positive feedback to achieve optical amplification and generate laser oscillation. It has been widely used in military and industrial fields such as laser weapons, laser guidance, laser ranging, industrial welding, and cutting. When a semiconductor laser normally operates, its voltage has an adaptive characteristic, which is determined by the series-connected LD load, and the stability of the injected current directly determines the stability of the output optical power.

[0003] Currently, according to the V-I curve and P-I curve of a semiconductor laser during operation, it shows that the operating state of the laser is extremely vulnerable to fluctuations in the output current of the drive power supply. Even a very small current spike may cause damage to the laser and shorten its service life. Usually, it is required that the overall output of the laser drive power supply is a constant current output, with high current stability and a small ripple coefficient. In order to reduce the current ripple of the laser drive power supply output and ensure the normal operating state of the semiconductor laser, therefore, we propose a device and method for controlling the current peak applied to a laser drive power supply. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem that the operating state of a semiconductor laser is extremely vulnerable to fluctuations in the output current of the drive power supply. Even a very small current spike may cause damage to the laser and shorten its service life. Usually, it is required that the overall output of the laser drive power supply is a constant current output, with high current stability and a small ripple coefficient. In order to reduce the current ripple of the laser drive power supply output and ensure the normal operating state of the semiconductor laser.

[0005] To achieve the above object, the present invention provides a device for controlling the current peak applied to a laser drive power supply, including a current sampling module, a precision adjustment module, a control comparison module, and a power supply main control module;

[0006] The current sampling module samples the output current of the laser drive power supply using a current sampling circuit. According to Ohm's law, it converts the collected current value into a voltage signal, filters it to remove noise interference, and transmits the voltage signal to the control comparison module;

[0007] The precision adjustment module combines the outputs of three PWM signals through a high-precision adjustment circuit. The output value of the first PWM signal is used as the high 8 bits of the adjustment precision, the output value of the second PWM signal is used as the middle 8 bits, and the output value of the third PWM signal is used as the low 8 bits. By regulating the duty cycle of each PWM signal, the output current of the laser driver power supply is adjusted with high precision. According to the power requirement of the laser driver power supply, the current reference value is determined and transmitted to the control comparison module;

[0008] The control comparison module uses the internal comparator of the digital signal processor to compare the current sampled by the current sampling module with the current reference value determined by the precision adjustment module, and regulates the current peak signal. At the same time, a closed-loop feedback control strategy is adopted to adaptively adjust the current peak signal according to different working modes and load changes of the laser driver power supply;

[0009] The power supply main control module outputs a drive control signal according to the current comparison result of the control comparison module, controls the on and off times of the switching transistor, regulates the current of the laser driver power supply, and further reduces the current ripple.

[0010] Preferably, the current sampling module includes a current sampling circuit, where the current sampling circuit includes a current transformer T1 and a diode D1;

[0011] The 4th pin of the current transformer T1 is connected to the positive pole of the diode D1. The negative pole of the diode D1 is connected to one end of the resistor R1, and is also connected to one end of the resistor R2 and one end of the capacitor C1. The 3rd pin of the current transformer T1 is connected to the other end of the resistor R1, and is also connected to the other end of the resistor R2 and the other end of the capacitor C1. The other end of the capacitor C1 is grounded.

[0012] Preferably, the precision adjustment module includes a pulse width regulation unit and a reference determination unit;

[0013] The pulse width regulation unit uses a high-precision adjustment circuit to regulate the duty cycle of each PWM signal and adjusts the output current of the laser driver power supply with high precision;

[0014] The reference determination unit determines the current reference value according to the power requirement of the laser driver power supply through the basic formula of power, current, and voltage.

[0015] Preferably, the pulse width regulation unit includes a high-precision adjustment circuit, where the high-precision adjustment circuit includes a capacitor C2 and a capacitor C3;

[0016] One end of the capacitor C2 is connected to one end of the resistor R6, and is also connected to one end of the resistor R3, one end of the resistor R4, and one end of the resistor R5. The other end of the resistor R6 is connected to one end of the resistor R7, and is also connected to one end of the capacitor C3. The other end of the capacitor C3 is connected to the other end of the resistor R7, and is also connected to the other end of the capacitor C2. The other end of the capacitor C2 is grounded.

[0017] Preferably, the pulse width modulation unit adopts interleaved PWM technology to stagger the phases of the three-way PWM by 120 degrees, so that the fluctuations of the output current are superimposed and compensated in time.

[0018] Preferably, the control and comparison module includes a comparison processing unit and a dynamic adjustment unit;

[0019] The comparison processing unit compares the output current of the laser drive power supply collected with the current reference value determined inside the digital signal processor, and adopts a closed-loop feedback control strategy to regulate the current peak signal;

[0020] The dynamic adjustment unit adaptively adjusts the current peak signal according to different working modes and load changes of the laser drive power supply.

[0021] Preferably, the comparison processing unit adopts a PID control algorithm to perform proportional control, integral control, and derivative control on the error, and generates a corresponding control signal according to the control quantity calculated by the PID control algorithm to regulate the current peak signal.

[0022] Preferably, the dynamic adjustment unit divides the working modes of the laser drive power supply into continuous wave mode, pulse mode, and modulation mode, and adaptively adjusts the current peak signal in different modes.

[0023] Preferably, the power supply main control module includes a power supply main control circuit, wherein the power supply main control circuit includes a switching transistor Q1, a current transformer T1, an inductor L1, and a diode D2;

[0024] The drain of the switching transistor Q1 is connected to one end of the capacitor C4, the source of the switching transistor Q1 is connected to the 2nd pin of the current transformer T1, the 1st pin of the current transformer T1 is connected to the negative electrode of the diode D2, and is also connected to one end of the inductor L1. The other end of the inductor L1 is connected to one end of the capacitor C5, the other end of the capacitor C5 is connected to the positive electrode of the diode D2, and is also connected to the other end of the capacitor C4. The other end of the capacitor C4 is grounded.

[0025] The second object of the present invention is to provide a method for controlling the current peak applied to a laser drive power supply, including the current peak control device applied to a laser drive power supply as described in any one of the above, and includes the following steps:

[0026] S1. Sample the output current of the laser driver power supply using a current sampling module, and filter the acquired signal;

[0027] S2. Combine the outputs of three PWM signals through a precision adjustment module, regulate the duty cycle of each PWM signal, perform high-precision adjustment on the output current of the laser driver power supply, and determine the current reference value;

[0028] S3. Compare the sampled output current of the laser driver power supply with the current reference value determined inside the digital signal processor using a control and comparison module, and adopt a closed-loop feedback control strategy to regulate the current peak signal;

[0029] S4. Output a drive control signal through the power supply main control module to control the on and off times of the switching transistor, regulate the current of the laser driver power supply, and further reduce the current ripple.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] The current peak control device and method applied to the laser driver power supply sample the output current of the laser driver power supply using a current sampling module, and filter the acquired signal. Combine the outputs of three PWM signals through a precision adjustment module, regulate the duty cycle of each PWM signal, perform high-precision adjustment on the output current of the laser driver power supply, and determine the current reference value. Compare the sampled output current of the laser driver power supply with the current reference value determined inside the digital signal processor using a control and comparison module, adopt a closed-loop feedback control strategy to regulate the current peak signal, maintain the current stability, and greatly reduce the ripple of the output current by using the high-precision adjustment of the output current of the laser driver power supply. Output a drive control signal through the power supply main control module to control the on and off times of the switching transistor, regulate the current of the laser driver power supply, and further reduce the current ripple, thereby ensuring that the overall output of the laser driver power supply is a constant current output, and having a high current stability and an extremely small ripple coefficient.

[0032] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The present invention will be further described in detail below with reference to the drawings. Description of the Drawings

[0033] Figure 1 It is the overall flow block diagram of the present invention;

[0034] Figure 2 It is the overall detailed flow chart of the present invention;

[0035] Figure 3 It is the current sampling circuit diagram of the present invention;

[0036] Figure 4 This is the high-precision adjustment circuit diagram of the present invention;

[0037] Figure 5 This is the power supply main control circuit diagram of the present invention;

[0038] Figure 6 This is the method flow block diagram of the present invention.

[0039] The meanings of each label in the figure are as follows:

[0040] 100. Current sampling module; 200. Precision adjustment module; 210. Pulse width control unit; 220. Determine reference unit; 300. Control comparison module; 310. Comparison processing unit; 320. Dynamic adjustment unit; 400. Power supply main control module. Specific embodiments

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] At present, the working state of semiconductor lasers is extremely vulnerable to the influence of the output current fluctuation of the driving power supply. Even a very small current spike may cause damage to the laser, shortening its service life. It is usually required that the whole machine output of the laser driving power supply is a constant current output, with high current stability and a small ripple coefficient. In order to reduce the current ripple of the laser driving power supply output and ensure the normal working state of the semiconductor laser.

[0043] Therefore, the present invention proposes to sample the output current of the laser driving power supply by using the current sampling module, filter the collected signal, combine the outputs of three-way PWM through the precision adjustment module, regulate the duty cycle of each PWM, perform high-precision adjustment on the output current of the laser driving power supply, and determine the current reference value. Use the control comparison module to compare the output current of the collected laser driving power supply with the current reference value determined inside the digital signal processor, adopt a closed-loop feedback control strategy to regulate the current peak signal, and output a drive control signal through the power supply main control module to control the on and off time of the switching tube, regulate the current of the laser driving power supply, and further reduce the current ripple.

[0044] Specifically as follows:

[0045] As Figure 1As shown in the figure, one of the objectives of the present invention is to provide a current peak control device applied to a laser driving power supply, which includes a current sampling module 100, a precision adjustment module 200, a control comparison module 300, and a power supply main control module 400;

[0046] The current sampling module 100 samples the output current of the laser driving power supply by using a current sampling circuit. According to Ohm's law, the sampled current value is converted into a voltage signal, and it is filtered to remove noise interference, and then this voltage signal is transmitted to the control comparison module 300;

[0047] The precision adjustment module 200 combines the outputs of three PWM signals through a high-precision adjustment circuit. The output value of the first PWM signal is used as the high 8 bits in the adjustment precision, the output value of the second PWM signal is used as the middle 8 bits, and the output value of the third PWM signal is used as the low 8 bits. By adjusting the duty cycle of each PWM signal, the output current of the laser driving power supply is adjusted with high precision. According to the power requirement of the laser driving power supply, the current reference value is determined and transmitted to the control comparison module 300;

[0048] The control comparison module 300 uses the internal comparator of the digital signal processor to compare the current collected by the current sampling module 100 with the current reference value determined by the precision adjustment module (200), and controls the current peak signal. At the same time, a closed-loop feedback control strategy is adopted to adaptively adjust the current peak signal according to different working modes and load changes of the laser driving power supply;

[0049] The power supply main control module 400 outputs a drive control signal according to the current comparison result of the control comparison module 300, controls the on and off times of the switching tube, and regulates the current of the laser driving power supply to further reduce the current ripple.

[0050] The current transformer is the core component of the current sampling circuit. It works based on the principle of electromagnetic induction. When the output current (primary side current) of the laser driving power supply passes through the primary winding of the current transformer, a secondary side current proportional to the primary side current will be induced in the secondary winding. By reasonably selecting the turns ratio of the current transformer, a large current can be converted into a small current for subsequent processing.

[0051] As Figure 3 shown, among them, the current sampling module 100 includes a current sampling circuit, and the current sampling circuit includes a current transformer T1 and a diode D1;

[0052] Pin 4 of the current transformer T1 is connected to the positive electrode of the diode D1. The negative electrode of the diode D1 is connected to one end of the resistor R1, and is also connected to one end of the resistor R2 and one end of the capacitor C1. Pin 3 of the current transformer T1 is connected to the other end of the resistor R1, and is also connected to the other end of the resistor R2 and the other end of the capacitor C1. The other end of the capacitor C1 is grounded.

[0053] In this circuit, the current transformer T1 is used to collect the output current of the laser driving power supply. When the output current (primary side current) of the laser driving power supply passes through the primary winding of the current transformer, a secondary side current proportional to the primary side current will be induced in the secondary winding. When current flows through the sampling resistor R1, a voltage drop proportional to the current will be generated across both ends of the resistor R1, so as to sample the output current of the laser driving power supply. The diode D1 ensures the unidirectional conduction of the current. The resistor R2 and the capacitor C1 form a filter circuit to filter out noise from the sampled current.

[0054] As Figure 2 shown, among them, the precision adjustment module 200 includes a pulse width control unit 210 and a reference determination unit 220;

[0055] The pulse width control unit 210 adopts a high-precision adjustment circuit to control the duty cycle of each PWM, so as to perform high-precision adjustment on the output current of the laser driving power supply;

[0056] The reference determination unit 220 determines the current reference value according to the power requirement of the laser driving power supply through the basic formula of power, current and voltage;

[0057] The output of the first PWM is used as part of the enable signal or clock signal of the second PWM. The output signal of the first PWM is logically combined with the original clock signal through a logic gate circuit (such as an AND gate or an OR gate). The output of the second PWM is connected to the third PWM in a similar manner, so that the three PWMs can work together. For example, the output value of the first PWM is used as the high 8 bits in the 24-bit adjustment precision, the output value of the second PWM is used as the middle 8 bits, and the output value of the third PWM is used as the low 8 bits, so as to achieve an overall adjustment precision of 24 bits.

[0058] As Figure 4 shown, among them, the pulse width control unit 210 includes a high-precision adjustment circuit, and among them, the high-precision adjustment circuit includes a capacitor C2 and a capacitor C3;

[0059] One end of the capacitor C2 is connected to one end of the resistor R6, and is also connected to one end of the resistor R3, one end of the resistor R4 and one end of the resistor R5. The other end of the resistor R6 is connected to one end of the resistor R7, and is also connected to one end of the capacitor C3. The other end of the capacitor C3 is connected to the other end of the resistor R7, and is also connected to the other end of the capacitor C2. The other end of the capacitor C2 is grounded.

[0060] In this circuit, resistors R3, R4, and R5 form a parallel resistor network. The resistance value of resistor R4 is 256 times that of resistor R3, and the resistance value of resistor R5 is 256 times that of resistor R4. By combining parallel resistors, the adjustment accuracy is achieved to be 65,536 times that of the original scheme. By regulating the duty cycle of each PWM, the output current of the laser drive power supply is accurately adjusted. Resistor R7 and capacitor C3 form a filter circuit to reduce the interference between PWM signals and the impact of power supply ripple on the adjustment accuracy.

[0061] In order to better eliminate the influence of current fluctuations, among them, the pulse width control unit 210 adopts the interleaved PWM technology, staggering the phases of the three PWMs by 120 degrees from each other, so that the fluctuations of the output current are superimposed and compensated in time;

[0062] Stagger the phases of the three PWMs from each other. For example, stagger their phases by 120 degrees in sequence. In this way, within a switching period, different PWM signals are in effect at different times, which is equivalent to increasing the equivalent multiple of the switching frequency, thereby making the change of the output current smoother, reducing the current ripple, and improving the adjustment accuracy. When a certain PWM signal is turned off, the PWM signals of other channels can continue to maintain the output of the current, avoiding the sudden change of the current, and enabling the current to more accurately track the set value.

[0063] The calculation of the adjustment accuracy is as follows:

[0064] Given that the input current is 33 A and the PWM adjustment accuracy is 8 bits, the value range that 8-bit PWM can represent is 0 - 255. The 3-way PWM in series realizes 24-bit adjustment accuracy, and the value range that 24 bits can represent is 0 - 16,777,215. At this time, the adjustment accuracy is:

[0065] 33 A÷(2 24 ) = 0.000196 mA;

[0066] The multiple relationship between the adjustment accuracy of the new scheme and the original scheme is:

[0067] 12.89 mA÷0.000196 mA = 65,536;

[0068] The adjustment accuracy of the new scheme is 65,536 times that of the original scheme.

[0069] Among them, the control and comparison module 300 includes a comparison and processing unit 310 and a dynamic adjustment unit 320;

[0070] The comparison and processing unit 310 compares the output current of the laser drive power supply collected with the current reference value determined inside the digital signal processor, and adopts a closed-loop feedback control strategy to regulate the current peak signal;

[0071] The dynamic adjustment unit 320 adaptively adjusts the current peak signal according to the different operating modes of the laser drive power supply and the load change situation;

[0072] Adopt a closed-loop feedback control strategy to compare the monitored actual parameter values with the set target values. If there is a deviation between the actual value and the target value, adjust the current peak reference signal through the microcontroller according to the magnitude and direction of the deviation. For example, when it is monitored that the optical power is lower than the set value, appropriately increase the current peak reference signal to increase the output power of the laser.

[0073] In order to better regulate the current peak signal, among them, the comparison and processing unit 310 adopts a PID control algorithm to perform proportional control, integral control, and derivative control on the error, and generates a corresponding control signal according to the control quantity calculated by the PID control algorithm to regulate the current peak signal;

[0074] The PID control algorithm calculates the control quantity based on the error of the system (the difference between the set value and the actual output value). It quickly responds to the error through the proportional link, eliminates the steady-state error through the integral link, and predicts the change trend of the error and makes adjustments in advance through the derivative link, so as to achieve precise control of the system;

[0075] Generate a corresponding control signal according to the control quantity calculated by the control algorithm. In the laser drive power supply, pulse width modulation (PWM) signals are usually used to control the on and off times of the power switch tubes, thereby regulating the output current. By adjusting the duty cycle of the PWM signal, the output power of the power supply is changed, and further the regulation of the current peak is achieved;

[0076] Continuously collect the output current of the laser drive power supply, compare it with the reference value, and adjust the control signal again according to the new error to form a closed-loop feedback control system to ensure that the output current can accurately track the reference value and precisely regulate the current peak.

[0077] In order to cope with the different operating modes of the laser drive power supply, among them, the dynamic adjustment unit 320 divides the operating modes of the laser drive power supply into continuous wave mode, pulse mode, and modulation mode, and adaptively adjusts the current peak signal in different modes;

[0078] Continuous wave mode: In the continuous wave operating mode, it is usually required to output a stable current to ensure that the laser continuously and stably outputs laser. At this time, a suitable initial current peak can be determined according to the power demand and efficiency characteristics of the laser. At the same time, monitor parameters such as the output power and temperature of the laser in real time. When it is found that the power fluctuates or the temperature changes, finely adjust the current peak signal to maintain a stable output;

[0079] Pulse mode: For the pulse operating mode, in addition to considering the average power, parameters such as the pulse frequency, duty cycle, and peak power also need to be concerned. According to different application requirements, for example, laser processing may require a high pulse peak power, while laser communication may have higher requirements for the accuracy and stability of the pulse. Combining with the characteristic curve of the laser, determine the peak current that matches the pulse parameters. When the pulse frequency or duty cycle changes, adjust the peak current signal accordingly to ensure that the energy and waveform of each pulse meet the requirements;

[0080] Modulation mode: In the modulation operating mode, such as amplitude modulation, frequency modulation, or phase modulation, etc., the peak current signal needs to be dynamically adjusted according to the change of the modulation signal. According to the modulation depth and frequency range, calculate the required current change range, and then through a real-time signal processing algorithm, convert the modulation signal into a corresponding peak current control signal, so that the output of the laser can accurately follow the change of the modulation signal.

[0081] As Figure 5 shown, among them, the power supply main control module 400 includes a power supply main control circuit, where the power supply main control circuit includes a switching transistor Q1, a current transformer T1, an inductor L1, and a diode D2;

[0082] The drain of the switching transistor Q1 is connected to one end of the capacitor C4, the source of the switching transistor Q1 is connected to the 2nd pin of the current transformer T1, the 1st pin of the current transformer T1 is connected to the negative electrode of the diode D2 and also connected to one end of the inductor L1, the other end of the inductor L1 is connected to one end of the capacitor C5, the other end of the capacitor C5 is connected to the positive electrode of the diode D2 and also connected to the other end of the capacitor C4, and the other end of the capacitor C4 is grounded.

[0083] In this circuit, one side of the current transformer T1 samples the current of the power supply main control circuit, and is transmitted to the current acquisition circuit through the other side of the current transformer T1. By controlling the on and off time of the switching transistor Q1, the current of the laser drive power supply is regulated. If the sampled current signal is less than the peak reference signal, the control circuit will output a signal to keep the switching transistor Q1 conducting or increase the conduction time to increase the current. If the sampled current signal reaches or exceeds the peak reference signal, the control circuit will output a signal to control the switching transistor Q1 to turn off or reduce the conduction time, thereby restricting the further increase of the current.

[0084] The second object of the present invention is to provide a peak current control method applied to a laser drive power supply, including the peak current control device applied to a laser drive power supply in any one of the above, as Figure 6 shown, including the following steps:

[0085] S1. Use the current sampling module 100 to sample the output current of the laser drive power supply and filter the acquired signal;

[0086] S2. Combine the outputs of the three-way PWM through the precision adjustment module 200, regulate the duty cycle of each PWM, perform high-precision adjustment on the output current of the laser driver power supply, and determine the current reference value;

[0087] S3. Use the control and comparison module 300 to compare the output current of the laser driver power supply collected with the current reference value determined inside the digital signal processor, and adopt a closed-loop feedback control strategy to regulate the current peak signal;

[0088] S4. Output a drive control signal through the power supply main control module 400 to control the on and off times of the switching transistor, regulate the current of the laser driver power supply, and further reduce the current ripple.

[0089] In summary, the working principle of this solution is as follows:

[0090] The device and method for controlling the current peak of the laser driver power supply sample the output current of the laser driver power supply by using the current sampling module 100 and filter the collected signal. Combine the outputs of the three-way PWM through the precision adjustment module 200, regulate the duty cycle of each PWM, perform high-precision adjustment on the output current of the laser driver power supply, and determine the current reference value. Use the control and comparison module 300 to compare the output current of the laser driver power supply collected with the current reference value determined inside the digital signal processor, adopt a closed-loop feedback control strategy to regulate the current peak signal, maintain the current stability, and use the high-precision adjustment of the output current of the laser driver power supply to greatly reduce the ripple of the output current. Output a drive control signal through the power supply main control module 400 to control the on and off times of the switching transistor, regulate the current of the laser driver power supply, and further reduce the current ripple, so as to ensure that the overall output of the laser driver power supply is a constant current output, and has a high current stability and an extremely small ripple coefficient.

[0091] The above shows and describes the basic principle, main features and advantages of the present invention. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions in the specification are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A current peak control device for a laser driving power supply, characterized in that: It comprises a current sampling module (100), a precision adjustment module (200), a control comparison module (300) and a power supply main control module (400); The current sampling module (100) samples the output current of the laser driving power supply using a current sampling circuit, converts the collected current value into a voltage signal according to Ohm's law, performs filtering on the voltage signal to remove noise interference, and transmits the voltage signal to the control comparison module (300); The precision adjustment module (200) combines the outputs of the three PWMs through a high-precision adjustment circuit, uses the output value of the first PWM as the high 8 bits of the adjustment precision, the output value of the second PWM as the middle 8 bits, and the output value of the third PWM as the low 8 bits, and adjusts the duty cycle of each PWM to adjust the output current of the laser driving power supply with high precision, determines the current reference value according to the power demand of the laser driving power supply, and transmits it to the control comparison module (300); The control comparison module (300) uses an internal comparator of a digital signal processor to compare the current collected by the current sampling module (100) with the current reference value determined by the precision adjustment module (200), thereby regulating the current peak signal, and at the same time, adopts a closed-loop feedback control strategy to adaptively adjust the current peak signal according to different working modes and load changes of the laser driving power supply; The power main control module (400) outputs a driving control signal according to the current comparison result of the control comparison module (300), controls the on and off time of the switch tube, regulates the current of the laser driving power supply, and further reduces the current ripple.

2. The current peak control device for laser driving power supply according to claim 1, characterized in that: The current sampling module (100) comprises a current sampling circuit, wherein the current sampling circuit comprises a current transformer T1 and a diode D1; Pin 4 of the current transformer T1 is connected to the positive electrode of the diode D1, the negative electrode of the diode D1 is connected to one end of the resistor R1, and is connected in parallel to one end of the resistor R2 and one end of the capacitor C1, pin 3 of the current transformer T1 is connected to the other end of the resistor R1, and is connected in parallel to the other end of the resistor R2 and the other end of the capacitor C1, and the other end of the capacitor C1 is grounded.

3. The current peak control device for laser driving power supply according to claim 1, characterized in that: The precision adjustment module (200) comprises a pulse width control unit (210) and a reference determination unit (220); The pulse width control unit (210) adopts a high-precision adjustment circuit to adjust the duty cycle of each PWM and perform high-precision adjustment on the output current of the laser driving power supply; The reference determination unit (220) determines the current reference value according to the power requirement of the laser driving power supply through a basic formula of power, current and voltage.

4. The current peak control device for laser driving power supply according to claim 3, characterized in that: The pulse width control unit (210) comprises a high-precision adjustment circuit, wherein the high-precision adjustment circuit comprises a capacitor C2 and a capacitor C3; One end of the capacitor C2 is connected to one end of the resistor R6, and is connected in parallel to one end of the resistor R3, one end of the resistor R4 and one end of the resistor R5. The other end of the resistor R6 is connected to one end of the resistor R7 and is connected in parallel to one end of the capacitor C3. The other end of the capacitor C3 is connected to the other end of the resistor R7 and is connected in parallel to the other end of the capacitor C2. The other end of the capacitor C2 is grounded.

5. The current peak control device for laser driving power supply according to claim 3, characterized in that: The pulse width control unit (210) adopts the staggered PWM technology to stagger the phases of the three PWMs by 120 degrees, so that the fluctuations of the output currents are superimposed and compensated in time.

6. The current peak control device for laser driving power supply according to claim 1, characterized in that: The control comparison module (300) comprises a comparison processing unit (310) and a dynamic adjustment unit (320); The comparison processing unit (310) compares the collected output current of the laser driving power supply with the current reference value determined inside the digital signal processor, and adopts a closed-loop feedback control strategy to regulate the current peak signal; The dynamic adjustment unit (320) adaptively adjusts the current peak signal according to different working modes and load changes of the laser driving power supply.

7. The current peak control device for laser driving power supply according to claim 6, characterized in that: The comparison processing unit (310) adopts a PID control algorithm to perform proportional control, integral control and differential control on the error, generates a corresponding control signal based on the control amount calculated by the PID control algorithm, and regulates the current peak signal.

8. The current peak control device for laser driving power supply according to claim 6, characterized in that: The dynamic adjustment unit (320) divides the working mode of the laser driving power supply into a continuous wave mode, a pulse mode and a modulation mode, and adaptively adjusts the current peak signal in different modes.

9. The current peak control device for laser driving power supply according to claim 1, characterized in that: The power main control module (400) comprises a power main control circuit, wherein the power main control circuit comprises a switch tube Q1, a current transformer T1, an inductor L1 and a diode D2; The drain of the switch tube Q1 is connected to one end of the capacitor C4, the source of the switch tube Q1 is connected to pin 2 of the current transformer T1, pin 1 of the current transformer T1 is connected to the cathode of the diode D2 and connected to one end of the inductor L1, the other end of the inductor L1 is connected to one end of the capacitor C5, the other end of the capacitor C5 is connected to the anode of the diode D2 and connected to the other end of the capacitor C4, and the other end of the capacitor C4 is grounded.

10. A method for implementing a current peak value control method for a laser driving power supply, comprising a current peak value control device for a laser driving power supply as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1, using a current sampling module (100) to sample the output current of the laser driving power supply, and filtering the collected signal; S2, combining the outputs of the three PWMs through the precision adjustment module (200), adjusting the duty cycle of each PWM, performing high-precision adjustment on the output current of the laser driving power supply, and determining a current reference value; S3, using a control comparison module (300) to compare the collected output current of the laser driving power supply with a current reference value determined inside the digital signal processor, and using a closed-loop feedback control strategy to regulate the current peak signal; S4. Outputting a driving control signal through the power main control module (400) to control the on and off time of the switch tube, regulating the current of the laser driving power supply, and further reducing the current ripple.

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