A pulse light power monitoring circuit and a monitoring method

Abstract

The embodiment of the application provides a kind of pulse light power monitoring circuit and monitoring method, belong to photoelectric detection technical field.The circuit includes main control module, transimpedance amplification module, peak sampling module and integral module, and photoelectric diode converts pulse light into photocurrent signal;Transimpedance amplification module carries out signal conversion to photocurrent signal, obtains voltage signal;Peak sampling module samples the peak of voltage signal, obtains peak voltage;Integral module carries out average calculation to voltage signal, obtains average voltage;Main control module carries out peak power calculation according to peak voltage and the structural parameter of peak sampling module, obtains peak power;According to average voltage and the structural parameter of integral module, average power is calculated, and average power is obtained;According to peak power and average power, the state of laser of emitting pulse light is evaluated, and evaluation result is obtained.The embodiment of the application can improve the comprehensiveness of pulse light power monitoring and the accuracy of laser state evaluation.

Description

Technical Field

[0001] This application relates to the field of photoelectric detection technology, and in particular to a pulsed light power monitoring circuit and monitoring method. Background Technology

[0002] With the continuous expansion of new energy grid connection, high-voltage direct current (HVDC) transmission is increasingly widely used in power systems due to its advantages such as large capacity, long distance, and high stability. In HVDC transmission systems, converter valves are the core equipment for realizing AC-DC energy conversion, and their operational reliability is directly related to the safety and stability of the entire transmission system.

[0003] Currently, in some high-voltage DC converter valve systems, the mainstream solution uses light-triggered thyristors (LTTs) as key components. These devices are directly triggered by laser pulses of a certain wavelength and power, and have advantages such as compact structure, strong anti-electromagnetic interference capability, and high reliability, thus having significant advantages in high-voltage applications.

[0004] However, the laser, optical fiber, and related driving components in the optically controlled thyristor drive chain will experience performance degradation and aging during long-term operation. Laser aging is usually manifested as the accumulation of defects in the active region, a decrease in radiative recombination efficiency, degradation of cavity surface reflection characteristics, an increase in contact resistance, and changes in thermal stress. These factors are coupled with each other, making it impossible for a single "present / absent" trigger signal to accurately reflect its health status.

[0005] In related technologies, peak power measurement of pulsed lasers often employs waveform analysis, equivalent sampling, or peak hold methods; average power measurement, on the other hand, relies heavily on offline waveform processing, making it difficult to simultaneously obtain both peak and average power, resulting in poor accuracy in laser condition assessment.

[0006] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention

[0007] The main objective of this application is to provide a pulsed light power monitoring circuit and method that can improve the comprehensiveness of pulsed light power monitoring and the accuracy of laser status assessment.

[0008] To achieve the above objectives, one aspect of this application provides a pulsed light power monitoring circuit, which includes a main control module, a transimpedance amplification module, a peak sampling module, and an integration module. The input terminal of the transimpedance amplification module is connected to a photodiode, and the output terminal of the transimpedance amplification module is connected to the input terminals of the peak sampling module and the integration module, respectively. The input terminal of the main control module is connected to the output terminals of the peak sampling module and the integration module, respectively. The photodiode is used to convert pulsed light into a photocurrent signal; The transimpedance amplifier module is used to convert the photocurrent signal into a voltage signal; The peak sampling module is used to sample the peak value of the voltage signal to obtain the peak voltage; The integration module is used to integrate and average the voltage signal to obtain the average voltage; The main control module is used to calculate the peak power based on the peak voltage and the structural parameters of the peak sampling module to obtain the peak power; to calculate the average power based on the average voltage and the structural parameters of the integration module to obtain the average power; and to perform a state assessment on the laser emitting the pulsed light based on the peak power and the average power to obtain the assessment result.

[0009] In some embodiments, the transimpedance amplification module includes a transimpedance amplification circuit and a first inverting amplifier. The transimpedance amplification circuit includes a first operational amplifier, a second resistor, a third resistor, a second capacitor, and a third capacitor. The non-inverting input terminal of the first operational amplifier is connected to ground in parallel through the third resistor and the third capacitor. The two ends of the parallel structure of the second resistor and the second capacitor are respectively connected to the inverting input terminal and the output terminal of the first operational amplifier. The output terminal of the first operational amplifier is connected to the inverting input terminal of the first inverting amplifier. The output terminal of the first inverting amplifier is respectively connected to the input terminals of the peak sampling module and the integration module. The transimpedance amplifier circuit is used to perform signal conversion on the photocurrent signal to obtain an initial voltage; The first inverting amplifier is used to adjust the polarity and amplitude of the initial voltage to obtain the voltage signal.

[0010] In some embodiments, the circuit further includes a sampling and control module, wherein the input terminal of the sampling and control module is connected to the output terminal of the transimpedance amplifier module, the first output terminal of the sampling and control module is connected to the control terminal of the peak sampling module and the control terminal of the integration module, and the second output terminal of the sampling and control module is connected to the input terminal of the main control module. The sampling and control module is used to output a sampling window signal to the main control module based on the voltage signal, and to send reset control signals to the peak sampling module and the integration module respectively.

[0011] In some embodiments, the sampling and control module includes a voltage comparator, a first differentiating circuit, a first-stage monostable multivibrator, a second differentiating circuit, and a second-stage monostable multivibrator; The non-inverting input of the voltage comparator serves as the input of the sampling and control module, and the inverting input of the voltage comparator receives the reference voltage. The voltage comparator, the first differentiating circuit, the first-stage monostable multivibrator, the second differentiating circuit, and the second-stage monostable multivibrator are connected in sequence. The output of the first-stage monostable multivibrator serves as the second output of the sampling and control module, and the output of the second-stage monostable multivibrator serves as the first output of the sampling and control module.

[0012] In some embodiments, the peak sampling module includes a transconductance amplifier, a diode, a holding capacitor, a voltage follower, and a first reset switch; The non-inverting input of the transconductance amplifier is connected to the output of the transimpedance amplifier module. The output of the transconductance amplifier is connected to the input of the diode. The output of the diode is connected to the non-inverting input of the voltage follower. The output of the voltage follower is connected to both the inverting input of the voltage follower and the inverting input of the transconductance amplifier. The two ends of the parallel structure of the holding capacitor and the first reset switch are connected to ground and the output of the diode, respectively.

[0013] In some embodiments, the first reset switch is a first NMOS transistor, the gate of the first NMOS transistor receives a reset control signal, the source of the first NMOS transistor is connected to ground, and the drain of the first NMOS transistor is connected to the output terminal of the diode. The first reset switch is used to reset the peak sampling module according to the reset control signal.

[0014] In some embodiments, the integration module includes an integration circuit, a second inverting amplifier, and a second reset switch. The output of the integration circuit is connected to the input of the second inverting amplifier, and the second reset switch is connected in parallel to the operational amplifier of the integration circuit. The integrating circuit is used to integrate the voltage signal to obtain the integrated voltage; The second inverting amplifier is used to adjust the polarity and amplitude of the integrated voltage to obtain the average voltage; The second reset switch is used to reset the integrator module according to the reset control signal.

[0015] In some embodiments, the second reset switch includes a second NMOS transistor and a third NMOS transistor; The source of the second NMOS transistor is connected to the source of the third NMOS transistor, the gate of the second NMOS transistor is connected to the gate of the third NMOS transistor, the drain of the second NMOS transistor is connected to the non-inverting input of the operational amplifier of the integrator circuit, and the drain of the second NMOS transistor is connected to the output of the operational amplifier of the integrator circuit.

[0016] To achieve the above objectives, another aspect of this application proposes a pulsed light power monitoring circuit method, which is applied to the pulsed light power monitoring circuit described in the above embodiments, and the method includes: Receive peak voltage and average voltage; The peak power is calculated based on the peak voltage and the structural parameters of the peak sampling module. The average power is calculated based on the average voltage and the structural parameters of the integrator module to obtain the average power. The laser emitting the pulsed light is evaluated based on the peak power and the average power to obtain the evaluation results.

[0017] In some embodiments, the state assessment of the laser emitting the pulsed light based on the peak power and the average power to obtain the assessment result includes: The pulse shape factor is calculated based on the peak power and the average power to obtain the current pulse shape factor; The normalized pulse shape factor is obtained by calculating the current pulse shape factor and the reference pulse shape factor. The evaluation result is determined based on the value of the normalized pulse morphology factor.

[0018] To achieve the above objectives, another aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method described above.

[0019] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the methods described above.

[0020] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer program product, including a computer program that, when executed by a processor, implements the aforementioned method.

[0021] The embodiments of this application include at least the following beneficial effects: This application provides a pulsed light power monitoring circuit, method, electronic device, storage medium, and program product. This solution obtains the peak power and average power of the pulsed laser simultaneously through a peak sampling module and an integration module, improving the comprehensiveness of pulsed light power monitoring. It can more comprehensively reflect the instantaneous output capability and long-term energy output capability of the laser, thereby providing a more reliable basis for assessing the health status of the laser and improving the accuracy of the assessment. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the pulsed light power monitoring circuit provided in the embodiments of this application; Figure 2 This is a schematic diagram of the transimpedance amplifier module provided in the embodiments of this application; Figure 3 This is a schematic diagram of the peak sampling module provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of the integration module provided in the embodiments of this application; Figure 5 This is a schematic diagram of the sampling and control module provided in an embodiment of this application; Figure 6 This is a flowchart of laser condition assessment provided in an embodiment of this application; Figure 7 This is a schematic diagram of the simulation results of the pulsed light power monitoring circuit provided in the embodiments of this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0025] Before providing a detailed description of the embodiments of this application, some of the nouns and terms involved in the embodiments of this application will be explained first. The nouns and terms involved in the embodiments of this application are subject to the following interpretations.

[0026] With the continuous expansion of new energy grid connection, high-voltage direct current (HVDC) transmission is increasingly widely used in power systems due to its advantages such as large capacity, long distance, and high stability. In HVDC transmission systems, converter valves are the core equipment for realizing AC-DC energy conversion, and their operational reliability is directly related to the safety and stability of the entire transmission system.

[0027] Currently, in some high-voltage DC converter valve systems, the mainstream solution uses light-triggered thyristors (LTTs) as key components. These devices are directly triggered by laser pulses of a certain wavelength and power, and have advantages such as compact structure, strong anti-electromagnetic interference capability, and high reliability, thus having significant advantages in high-voltage applications.

[0028] However, the laser, optical fiber, and related driving components in the optical thyristor drive chain will experience performance degradation and aging during long-term operation. Existing monitoring methods mostly remain at the level of a rough judgment based on "whether there is a trigger signal," lacking the ability to quantitatively analyze the laser's output capability, degradation trend, and health status. It is necessary to expand the optical power online monitoring function based on the existing optical transmitter and receiver boards of the LTT valve, and send the measurement results to the backend display. Simultaneously, aging assessment and fault type determination should be performed by combining data from both the transmitter and receiver ends.

[0029] Laser aging typically manifests as the accumulation of defects in the active region, decreased radiative recombination efficiency, degradation of cavity surface reflection characteristics, increased contact resistance, and changes in thermal stress. These factors are interconnected, making a single "present / absent" trigger signal insufficient to accurately reflect the laser's health status. In related technologies, peak power measurement of pulsed lasers often employs waveform analysis, equivalent sampling, or peak hold methods; average power measurement largely relies on offline waveform processing. These methods generally suffer from insufficient real-time performance, reading lag, susceptibility to device voltage drop errors, or dependence on precise microcontroller-generated reset timing. Their applicability is limited in the field environment of converter valves with multiple pulses, variable frequencies, and strong electromagnetic interference.

[0030] In view of this, this application provides a pulsed light power monitoring circuit and method. This scheme obtains the peak power and average power of the pulsed laser simultaneously through a peak sampling module and an integration module, thereby improving the comprehensiveness of pulsed light power monitoring. It can more comprehensively reflect the instantaneous output capability and long-term energy output capability of the laser, thus providing a more reliable basis for assessing the health status of the laser and improving the accuracy of the assessment.

[0031] Figure 1This is an optional structural diagram of the pulsed light power monitoring circuit provided in the embodiments of this application. The circuit includes a main control module, a transimpedance amplification module, a peak sampling module, and an integration module. The input terminal of the transimpedance amplification module is connected to a photodiode, and the output terminal of the transimpedance amplification module is connected to the input terminals of the peak sampling module and the integration module, respectively. The input terminal of the main control module is connected to the output terminals of the peak sampling module and the integration module, respectively. The photodiode is used to convert pulsed light into a photocurrent signal; The transimpedance amplifier module is used to convert the photocurrent signal into a voltage signal; The peak sampling module is used to sample the peak value of the voltage signal to obtain the peak voltage; The integration module is used to integrate and average the voltage signal to obtain the average voltage; The main control module is used to calculate the peak power based on the peak voltage and the structural parameters of the peak sampling module to obtain the peak power; to calculate the average power based on the average voltage and the structural parameters of the integration module to obtain the average power; and to perform a state assessment on the laser emitting the pulsed light based on the peak power and the average power to obtain the assessment result.

[0032] Specifically, the photodiode receives the monitoring optical path split by the beam splitter and converts the pulsed light into a photocurrent signal; the transimpedance amplifier module converts the photocurrent signal into a voltage signal and adjusts its amplitude and buffers the output; the peak sampling module extracts and holds the peak value of the voltage signal corresponding to the pulsed laser to reflect the peak power of the trigger laser; the integrator module integrates the voltage signal to reflect the average power of the trigger laser; and the main control module can be a digital signal processor (DSP).

[0033] In some embodiments, the transimpedance amplification module includes a transimpedance amplification circuit and a first inverting amplifier. The transimpedance amplification circuit includes a first operational amplifier, a second resistor, a third resistor, a second capacitor, and a third capacitor. The non-inverting input terminal of the first operational amplifier is connected to ground in parallel through the third resistor and the third capacitor. The two ends of the parallel structure of the second resistor and the second capacitor are respectively connected to the inverting input terminal and the output terminal of the first operational amplifier. The output terminal of the first operational amplifier is connected to the inverting input terminal of the first inverting amplifier. The output terminal of the first inverting amplifier is respectively connected to the input terminals of the peak sampling module and the integration module. The transimpedance amplifier circuit is used to perform signal conversion on the photocurrent signal to obtain an initial voltage; The first inverting amplifier is used to adjust the polarity and amplitude of the initial voltage to obtain the voltage signal.

[0034] Specifically, please refer to Figure 2 A photodiode can be equivalent to a photocurrent signal I. p The junction capacitance C1 and the dark current equivalent resistance R1. After the pulsed laser output from the laser is split, the optical power of its monitoring branch and the photodiode responsivity R... o The photocurrent signal magnitude is determined by these factors. The transimpedance amplifier circuit includes a first operational amplifier A1, a third resistor R3, a third capacitor C3, a feedback resistor (second resistor) R2, and a feedback capacitor (second capacitor) C2, simultaneously satisfying gain and bandwidth requirements. The non-inverting input of A1 is connected to ground in parallel via the third resistor R3 and the third capacitor C3, where R3 = R2 and C3 = C1 + C2. The equivalent resistance R1 is very large, I in ≈I p Therefore, the photocurrent signal I is converted using the second resistor R2. p Converted to initial voltage V TIA The relationship between the two is shown in equation (1). By reasonably selecting the second resistor R2 and the second capacitor C2, the output voltage can be kept within the allowable input range of the subsequent ADC while meeting the bandwidth requirements.

[0035] (1); The transimpedance amplifier circuit has a high output impedance. If it directly drives the peak sampling module, integration module, and sampling and control module, the output amplitude may decrease, the bandwidth may narrow, or even oscillate due to the load effect of the subsequent stage. Therefore, a first inverting amplifier is set after the transimpedance amplifier circuit to convert V... TIA This serves as the input to the inverting amplifier. The inverting amplifier includes a second operational amplifier A2, resistors R4 and R5, which adjust the voltage polarity to facilitate subsequent processing of the output signal. Its output voltage is the output voltage signal V from the transimpedance amplifier module. OUT , with V TIA The relationship is shown in equation (2); on the other hand, the inverting amplifier operates in the linear region and is in deep negative feedback, providing low output impedance, improving the driving capability of multiple downstream units, reducing the impact of load effects, and improving the stability of the entire monitoring link.

[0036] (2); In some embodiments, the peak sampling module includes a transconductance amplifier, a diode, a holding capacitor, a voltage follower, and a first reset switch; The non-inverting input of the transconductance amplifier is connected to the output of the transimpedance amplifier module. The output of the transconductance amplifier is connected to the input of the diode. The output of the diode is connected to the non-inverting input of the voltage follower. The output of the voltage follower is connected to both the inverting input of the voltage follower and the inverting input of the transconductance amplifier. The two ends of the parallel structure of the holding capacitor and the first reset switch are connected to ground and the output of the diode, respectively.

[0037] Specifically, please refer to Figure 2 The peak sampling module includes a transconductance amplifier A3 and a diode. D 1. Maintain capacitor C 4. Voltage follower A4 and the first reset switch. When the voltage signal... V OUT Rise and exceed holding capacitance C When the voltage across terminals 4 is constant, the transconductance amplifier A3 outputs a charging current based on the difference between the two voltages. i 1. Make the diode D 1. Conduction, maintaining capacitor C 4. Fast charging; when the voltage signal... V OUT During the descent, due to the holding capacitor C 4. Voltage higher than voltage signal V OUT ,diode D 1. Cut off, maintain capacitor C 4. Maintain the previously reached maximum voltage, thus achieving peak hold. The peak voltage output by the peak sampling module... V PEAK With voltage signal V OUT The relationship is shown in equation (3).

[0038] (3); Compared to conventional peak-hold circuits, the transconductance peak detection structure reduces overshoot errors caused by parasitic capacitance and feedback delay, making it more suitable for high-speed pulse scenarios. To minimize the impact of parasitic parameters from subsequent ADC stages, sample-and-hold circuits, or wiring on the holding capacitor voltage, a voltage follower A4 is placed after the holding capacitor. The voltage follower features high input impedance and low output impedance, reducing the extraction of holding charge while providing sufficient drive capability for subsequent readout.

[0039] In some embodiments, the first reset switch is a first NMOS transistor, the gate of the first NMOS transistor receives a reset control signal, the source of the first NMOS transistor is connected to ground, and the drain of the first NMOS transistor is connected to the output terminal of the diode. The first reset switch is used to reset the peak sampling module according to the reset control signal.

[0040] Specifically, please refer to Figure 2 First reset switch and holding capacitor C 4 parallel configuration, including the first NMOS transistor T 1. When a reset control signal is received V CONTROL At that time, the first NMOS transistor T 1. When the capacitor is turned on, it holds the capacitor. C 4. Perform rapid discharge; when V CONTROL After completion, the first NMOS transistor T 1. When shut down, the peak sampling module returns to its initial test state.

[0041] In some embodiments, the integration module includes an integration circuit, a second inverting amplifier, and a second reset switch. The output of the integration circuit is connected to the input of the second inverting amplifier, and the second reset switch is connected in parallel to the operational amplifier of the integration circuit. The integrating circuit is used to integrate the voltage signal to obtain the integrated voltage; The second inverting amplifier is used to adjust the polarity and amplitude of the integrated voltage to obtain the average voltage; The second reset switch is used to reset the integrator module according to the reset control signal.

[0042] Specifically, please refer to Figure 4 The integration module is used to characterize the total energy of the pulsed laser within one pulse cycle, thereby obtaining a measurement related to the average power. The integration module includes an integrating circuit, a second inverting amplifier, and a second reset switch.

[0043] The integrating circuit includes operational amplifier A5 and resistors. R 6 Resistance R 7 and capacitors C 5. During the pulse duration, the input voltage signal V OUT The integrating capacitor is processed by the integrating circuit. C 5. Continuous charging causes operational amplifier A5 to output an integrated voltage. V o With voltage signal V OUT The integral result with respect to time is shown in equation (4). This is because the voltage signal output by the transimpedance amplifier module... V OUT Trends in pulsed light power PThe trend of change is consistent, so the output of the integration module can be used to reflect the energy characteristics within a pulse cycle; after combining the pulse cycle information, the average power can be calculated.

[0044] (4); Integrator circuit output V o The polarity can be reversed and the amplitude adjusted by an inverting amplifier to make it more suitable for sampling by the subsequent ADC. The second inverting amplifier circuit includes operational amplifier A6 and resistors. R 8 、R 9. Its output voltage is the average output voltage of the integrating module. V AV Average voltage V AV With integral voltage V o The relationship is shown in equation (5).

[0045] (5); In some embodiments, the second reset switch includes a second NMOS transistor and a third NMOS transistor; The source of the second NMOS transistor is connected to the source of the third NMOS transistor, the gate of the second NMOS transistor is connected to the gate of the third NMOS transistor, the drain of the second NMOS transistor is connected to the non-inverting input of the operational amplifier of the integrator circuit, and the drain of the second NMOS transistor is connected to the output of the operational amplifier of the integrator circuit.

[0046] Specifically, please refer to Figure 4 To reduce the impact of residual charge in the integrating capacitor on the measurement results of the next pulse, this embodiment includes a second reset switch across the integrating capacitor. The second reset switch comprises two identical NMOS transistors (second NMOS transistor) T2 and (third NMOS transistor) T3, connected back-to-back. Specifically, their drains are connected across capacitor C5, their sources are shorted, and their gates are also shorted. The reset control signal V... CONTROL By connecting the gates of the two diodes, a bidirectional low-resistance discharge path is formed when the diode is turned on, and the parasitic conduction effect caused by the body diode is effectively suppressed when the diode is turned off, thereby improving the accuracy and reliability of the reset.

[0047] In some embodiments, the circuit further includes a sampling and control module, wherein the input terminal of the sampling and control module is connected to the output terminal of the transimpedance amplifier module, the first output terminal of the sampling and control module is connected to the control terminal of the peak sampling module and the control terminal of the integration module, and the second output terminal of the sampling and control module is connected to the input terminal of the main control module. The sampling and control module is used to output a sampling window signal to the main control module based on the voltage signal, and to send reset control signals to the peak sampling module and the integration module respectively.

[0048] Specifically, the sampling and control module is used to automatically generate a sampling window signal after the pulse ends, and output a reset control signal after sampling is completed, so that the peak sampling module and the integration module return to their initial state and wait for the next pulse to arrive.

[0049] In some embodiments, the sampling and control module includes a voltage comparator, a first differentiating circuit, a first-stage monostable multivibrator, a second differentiating circuit, and a second-stage monostable multivibrator; The non-inverting input of the voltage comparator serves as the input of the sampling and control module, and the inverting input of the voltage comparator receives the reference voltage. The voltage comparator, the first differentiating circuit, the first-stage monostable multivibrator, the second differentiating circuit, and the second-stage monostable multivibrator are connected in sequence. The output of the first-stage monostable multivibrator serves as the second output of the sampling and control module, and the output of the second-stage monostable multivibrator serves as the first output of the sampling and control module.

[0050] Specifically, please refer to Figure 5 The voltage comparator includes a seventh operational amplifier A7, and the first differentiating circuit includes a resistor R. 10 The system includes capacitor C6 and a 5V pull-up power supply. The first-stage monostable trigger includes a timing integrated circuit chip NE555 and a resistor R. 11 Along with capacitors C7 and C8, the second differentiating circuit includes resistor R. 12 The system includes capacitor C9 and a 3.3V pull-up power supply. The second-stage monostable trigger includes a timing integrated circuit chip NE555 and a resistor R. 13 and capacitor C 10 C 11 .

[0051] The voltage comparator converts the voltage signal output by the transimpedance amplifier module. V OUT With preset threshold V REF Compare them. If A7 is powered by a single 5V power supply, when the voltage signal... V OUT Higher than reference voltage V REF When the voltage signal is high, it outputs a 5V high level; when the voltage signal is low... V OUT Below reference voltage V REFWhen the trigger pulse laser has a fast rise and fall edge, the high-level range of the comparator output can approximately cover the entire effective pulse duration. Therefore, the falling edge of the voltage comparator output can approximately correspond to the end of the laser pulse.

[0052] If the falling edge of the comparator output is used directly to control the reset, the peak sampling module and the integration module will be reset prematurely before the result reading is completed, severely affecting the measurement accuracy. Therefore, in this embodiment, the falling edge of the comparator output is first converted into a narrow pulse trigger signal by the first differentiating circuit, and then the first-stage monostable multivibrator outputs a sampling window signal for a certain period of time. When the comparator output changes from 0V low level to 5V high level, the first differentiating circuit converts the rising edge into a positive spike of 5V and slowly drops to 0V, with the duration being the time the comparator holds a high level; when the voltage comparator output changes from 5V high level to 0V low level, they again convert the falling edge into a negative spike of -5V and slowly return to 0V, with the duration being the same as before; to meet the triggering condition of the monostable multivibrator, the trigger signal should be lower than V cc / 3, of which V cc The supply voltage for the NE555 must be specified, and the trigger time must not exceed the operating time of the monostable multivibrator. R 10 Then, a 5V pull-up power supply is added to shift the two spike signals up by 5V throughout the entire process. At this time, only the -5V reverse spike corresponding to the falling edge of the comparator can trigger the monostable multivibrator to work normally, reducing false triggering.

[0053] After the first-stage monostable multivibrator is successfully triggered, it outputs a high level with the same amplitude as the power supply connected to the RST port, i.e., 5V, for a duration of [duration missing]. T on1 and R 11 , C The relationship of 8 is shown in equation (6). T on1 After completion, the voltage returns to 0V. The above description refers to the sampling window signal. V SAMP .

[0054] This embodiment also provides a pulsed optical power monitoring circuit method, which is applied to the pulsed optical power monitoring circuit as described in the above embodiment. The method may include, but is not limited to, steps S101 to S104: Step S101: Receive peak voltage and average voltage; Step S102: Calculate the peak power based on the peak voltage and the structural parameters of the peak sampling module to obtain the peak power; Step S103: Calculate the average power based on the average voltage and the structural parameters of the integrator module to obtain the average power; Step S104: The laser emitting the pulsed light is evaluated based on the peak power and the average power to obtain the evaluation result.

[0055] In step S102 of some embodiments, the sampling window signal V SAMP The rising edge can serve as a sampling start marker for the main control module. During the duration of this window, the peak measured voltage... V PEAK and integral voltage measurement V AV Maintaining stability facilitates data reading by subsequent stages.

[0056] (6); By reading the peak voltage of the peak sampling module V PEAK From peak voltage V PEAK Derive the peak power of the trigger laser P PEAK The relationship is shown in equation (7), where R 2 is the feedback resistor of the transimpedance amplifier circuit. R o This represents the responsivity of the photodiode at a corresponding wavelength. α This refers to the spectrophotometric ratio.

[0057] (7); In step S103 of some embodiments, the average voltage output by the integration module is used as a basis. V AV Derive the average power of the triggered laser P AV As shown in equation (8), where T This is the pulse period.

[0058] (8); In some embodiments, step S104 may include, but is not limited to, steps S401 to S403: Step S401: Calculate the pulse shape factor based on the peak power and the average power to obtain the current pulse shape factor; Step S402: Calculate the current pulse morphology factor and the reference pulse morphology factor to obtain the normalized pulse morphology factor; Step S403: Determine the evaluation result based on the value of the normalized pulse morphology factor.

[0059] In some embodiments, please refer to steps S401 to S403. Figure 6 Let the first k The peak power and average power corresponding to each pulse of light are respectively P PEAK，k , P AV , k When the system is running for the first time or the laser is in a healthy state, a period of stable operation is selected as a reference stage. The peak power and average power within this stage are statistically averaged to obtain the initial reference value for health. P PEAK，0 and P AV，0 Define pulse morphology factor S k Its expression is shown in equation (9), then P PEAK，0 and P AV，0 Corresponding reference pulse morphology factor S 0. DSP calculates the current pulse shape factor. S k The normalized pulse morphology factor is obtained by comparing it with a reference value. S n ( k ), whose expression is shown in equation (10).

[0060] (9); (10); When peak power and average power change, if the normalized pulse shape factor remains around 1, it indicates that the peak and average values ​​change relatively synchronously, and the laser is more likely to be in a state of overall output attenuation. If the normalized shape factor remains greater than 1, it indicates that the peak value decreases faster, and the laser's instantaneous excitation capability is more likely to degrade first. If the normalized shape factor remains less than 1, it indicates that the average power decreases faster, and the laser's pulse sustaining capability or thermal stability is more likely to become the main deterioration factor.

[0061] In some embodiments, please refer to Figure 6 A trigger safety margin criterion is introduced. Let the minimum required peak power be Ptrig, and define the trigger safety margin Rtrig(k), the expression of which is shown in equation (11). When this safety margin is lower than the preset threshold, it can be directly determined that there is a trigger risk in the system, thereby issuing an early warning signal in advance.

[0062] (11).

[0063] This embodiment uses a pure hardware approach to implement sampling and reset timing control. It does not require prior knowledge of the pulse frequency or microprocessor generation of the reset timing, and has advantages such as fast response speed, strong anti-interference ability, and strong adaptability to pulse frequency changes. Under the condition that the photodiode does not saturate, it can monitor a wide range of power fluctuations. By simultaneously acquiring the peak power and average power of the trigger laser, it can realize online evaluation of the laser aging status, output capability, and drive link health status, providing a basis for laser fault early warning and lifespan prediction.

[0064] In some embodiments, a simulation test is performed on the pulsed light power monitoring circuit, and the simulation results of the monitoring circuit are as follows: Figure 7 As shown, the pulsed laser output from the laser is converted into a photocurrent signal by a photodiode. I p The subsequent waveform is an irregular square wave, representing the voltage signal output by the transimpedance amplifier module. V OUT With photocurrent signal I p The waveforms are similar and have an approximately linear relationship. In this embodiment, V OUT The voltage range is set between 0-3V to meet the voltage requirements of the DSP; t At time 1, the voltage signal V OUT The value increases and exceeds the reference voltage. V REF The voltage comparator A7 outputs a 5V high level. t At time 2, the voltage signal V OUT The value decreased and fell below the reference voltage. V REF The comparator outputs a 0V low level; when compared with... t At a very close moment, the falling edge of the comparator output triggers the first-stage monostable multivibrator to operate, generating the sampling window signal. V SAMP ,continued T on1 It then disappears; at almost the same moment that the signal disappears during the sampling window. t 3. Sampling window signal V SAMP The falling edge of the signal triggers the second-stage monostable multivibrator to activate, generating a reset control signal. V CONTROL During its duration T on2 Inside, the reset switches of the peak sampling module and the integration module are activated, causing the capacitor... C 4.C 5. Discharge, peak voltage V PEAK and average voltage V AV Gradually decrease to 0; t At time 4, reset control signal V CONTROL Disappeared, reset switch stopped working, capacitor C 4. C 5. Discharge ceases, and the peak sampling module and integration module return to their initial state.

[0065] It is understood that the content of the above method embodiments is applicable to the present device embodiments. The specific functions implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0066] This application also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described method. This electronic device can be any smart terminal, including tablet computers, in-vehicle computers, etc.

[0067] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0068] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.

[0069] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0070] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0071] It is understood that the content of the above method embodiments is applicable to the embodiments of this program product. The specific functions implemented by the embodiments of this program product are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0072] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0073] The pulsed light power monitoring circuit, method, electronic device, storage medium, and program product provided in this application have at least the following beneficial effects: This embodiment simultaneously acquires the peak power and average power of the pulsed laser. Compared with the traditional method that only determines the presence or absence of a trigger signal, it can more comprehensively reflect the instantaneous output capability and long-term energy output capability of the laser, thereby providing a more reliable basis for laser health status assessment, lifetime prediction and fault diagnosis.

[0074] This embodiment uses a comparator, a differentiator circuit, and two-stage monostable multivibrators to form a pure hardware timing control link. It does not require the microprocessor to pre-generate the reset control timing. It can automatically complete sampling and reset based on the input pulse from its own edge, which significantly improves the adaptability to unknown frequency pulses or frequency fluctuation pulses.

[0075] In this embodiment, the irregular voltage waveform after photoelectric conversion is converted into a square wave by a comparator. The fluctuation of this voltage signal between the comparator reference voltage and its maximum value will not affect the output of the comparator and subsequent sampling and reset control signals, thus realizing a wide range of laser power measurement.

[0076] This embodiment solves the problem of measurement value disturbance caused by the discharge moment in the integrating circuit and the peak hold circuit by separating the "sampling action" and the "reset action" in time, thereby improving the stability and accuracy of the peak measurement result and the average measurement result.

[0077] The reverse amplification, voltage follower, differential triggering, and back-to-back reset switch designs in this embodiment collectively reduce the load effect, false triggering risk, and reset interference of the subsequent stage, making the circuit more suitable for on-site online monitoring of converter valves in high-voltage and strong electromagnetic interference environments.

[0078] This embodiment can be further used in conjunction with receiver optical power monitoring, background display and fault diagnosis modules to assist in the judgment of trigger board faults, fiber optic link faults and device aging trends by comparing data from the transmitter and receiver.

[0079] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0080] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0081] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0082] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0083] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0084] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0085] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0086] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0087] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0088] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0089] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A pulsed light power monitoring circuit, characterized in that, The circuit includes a main control module, a transimpedance amplifier module, a peak sampling module, and an integration module. The input terminal of the transimpedance amplifier module is connected to a photodiode, and the output terminal of the transimpedance amplifier module is connected to the input terminals of the peak sampling module and the integration module, respectively. The input terminal of the main control module is connected to the output terminals of the peak sampling module and the integration module, respectively. The photodiode is used to convert pulsed light into a photocurrent signal; The transimpedance amplifier module is used to convert the photocurrent signal into a voltage signal; The peak sampling module is used to sample the peak value of the voltage signal to obtain the peak voltage; The integration module is used to integrate and average the voltage signal to obtain the average voltage; The main control module is used to calculate the peak power based on the peak voltage and the structural parameters of the peak sampling module to obtain the peak power; to calculate the average power based on the average voltage and the structural parameters of the integration module to obtain the average power; and to perform a state assessment on the laser emitting the pulsed light based on the peak power and the average power to obtain the assessment result.

2. The circuit according to claim 1, characterized in that, The transimpedance amplification module includes a transimpedance amplification circuit and a first inverting amplifier. The transimpedance amplification circuit includes a first operational amplifier, a second resistor, a third resistor, a second capacitor, and a third capacitor. The non-inverting input terminal of the first operational amplifier is connected to ground in parallel through the third resistor and the third capacitor. The two ends of the parallel structure of the second resistor and the second capacitor are respectively connected to the inverting input terminal and the output terminal of the first operational amplifier. The output terminal of the first operational amplifier is connected to the inverting input terminal of the first inverting amplifier. The output terminal of the first inverting amplifier is respectively connected to the input terminals of the peak sampling module and the integration module. The transimpedance amplifier circuit is used to perform signal conversion on the photocurrent signal to obtain an initial voltage; The first inverting amplifier is used to adjust the polarity and amplitude of the initial voltage to obtain the voltage signal.

3. The circuit according to claim 1, characterized in that, The circuit also includes a sampling and control module. The input terminal of the sampling and control module is connected to the output terminal of the transimpedance amplifier module. The first output terminal of the sampling and control module is connected to the control terminal of the peak sampling module and the control terminal of the integration module, respectively. The second output terminal of the sampling and control module is connected to the input terminal of the main control module. The sampling and control module is used to output a sampling window signal to the main control module based on the voltage signal, and to send reset control signals to the peak sampling module and the integration module respectively.

4. The circuit according to claim 3, characterized in that, The sampling and control module includes a voltage comparator, a first differentiating circuit, a first-stage monostable multivibrator, a second differentiating circuit, and a second-stage monostable multivibrator. The non-inverting input of the voltage comparator serves as the input of the sampling and control module, and the inverting input of the voltage comparator receives the reference voltage. The voltage comparator, the first differentiating circuit, the first-stage monostable multivibrator, the second differentiating circuit, and the second-stage monostable multivibrator are connected in sequence. The output of the first-stage monostable multivibrator serves as the second output of the sampling and control module, and the output of the second-stage monostable multivibrator serves as the first output of the sampling and control module.

5. The circuit according to claim 1, characterized in that, The peak sampling module includes a transconductance amplifier, a diode, a holding capacitor, a voltage follower, and a first reset switch; The non-inverting input of the transconductance amplifier is connected to the output of the transimpedance amplifier module. The output of the transconductance amplifier is connected to the input of the diode. The output of the diode is connected to the non-inverting input of the voltage follower. The output of the voltage follower is connected to both the inverting input of the voltage follower and the inverting input of the transconductance amplifier. The two ends of the parallel structure of the holding capacitor and the first reset switch are connected to ground and the output of the diode, respectively.

6. The circuit according to claim 5, characterized in that, The first reset switch is a first NMOS transistor. The gate of the first NMOS transistor receives a reset control signal, the source of the first NMOS transistor is connected to ground, and the drain of the first NMOS transistor is connected to the output terminal of the diode. The first reset switch is used to reset the peak sampling module according to the reset control signal.

7. The circuit according to claim 1, characterized in that, The integration module includes an integration circuit, a second inverting amplifier, and a second reset switch. The output of the integration circuit is connected to the input of the second inverting amplifier, and the second reset switch is connected in parallel to the operational amplifier of the integration circuit. The integrating circuit is used to integrate the voltage signal to obtain the integrated voltage; The second inverting amplifier is used to adjust the polarity and amplitude of the integrated voltage to obtain the average voltage; The second reset switch is used to reset the integrator module according to the reset control signal.

8. The circuit according to claim 7, characterized in that, The second reset switch includes a second NMOS transistor and a third NMOS transistor; The source of the second NMOS transistor is connected to the source of the third NMOS transistor, the gate of the second NMOS transistor is connected to the gate of the third NMOS transistor, the drain of the second NMOS transistor is connected to the non-inverting input of the operational amplifier of the integrator circuit, and the drain of the second NMOS transistor is connected to the output of the operational amplifier of the integrator circuit.

9. A method for monitoring pulsed optical power, characterized in that, The method is applied to the pulsed light power monitoring circuit as described in any one of claims 1 to 8, and the method includes: Receive peak voltage and average voltage; The peak power is calculated based on the peak voltage and the structural parameters of the peak sampling module. The average power is calculated based on the average voltage and the structural parameters of the integrator module to obtain the average power. The laser emitting the pulsed light is evaluated based on the peak power and the average power to obtain the evaluation results.

10. The method according to claim 9, characterized in that, The process of evaluating the state of the laser emitting the pulsed light based on the peak power and the average power to obtain evaluation results includes: The pulse shape factor is calculated based on the peak power and the average power to obtain the current pulse shape factor; The normalized pulse shape factor is obtained by calculating the current pulse shape factor and the reference pulse shape factor. The evaluation result is determined based on the value of the normalized pulse morphology factor.

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