A method and apparatus for safety interlocking of fiber lasers

Abstract

The application discloses a kind of optical fiber laser safety interlocking method and device, it is related to laser control field.The method comprises: when receiving light-emitting command, the first pre-discharge in control optical fiber laser is started, after the current of first pre-discharge reaches first set current, sequentially control the second pre-discharge in fiber laser and the main discharge start based on the PWM wave of set duty ratio and received response instruction;After optical fiber laser starts, the duty ratio of PWM wave is detected in real time, if the duty ratio of PWM wave is not equal to set duty ratio, sequentially control the main discharge in optical fiber laser, second pre-discharge and first pre-discharge are closed.The application can realize the safety interlocking of optical fiber laser, improve the response speed of fault, avoid device damage.

Description

Technical Field

[0001] This application relates to the field of laser control, and in particular to a method and apparatus for safety interlocking of fiber lasers. Background Technology

[0002] Fiber lasers achieve high-power output through a step-by-step amplification process involving a primary preamplifier, a secondary preamplifier, and a main amplifier. To ensure laser safety, the primary preamplifier, secondary preamplifier, and main amplifier must be turned on sequentially during light output, and turned off sequentially in the same order.

[0003] In related technologies, the timing of the laser's progressive loading and shut-off current is centrally controlled by the power control module through software communication. The drive modules of the first-stage preamplifier, second-stage preamplifier, and main amplifier do not communicate directly with each other; all three communicate with the power control module. Therefore, the start-up, shutdown, and current loading of the three drive modules are all centrally controlled by the power control module using software timing control.

[0004] Centralized software timing control flow such as Figure 1 and Figure 2 As shown. Figure 1 As shown, after receiving the light output command from the superior unit, the power control module first sends a start command to the first-level preamplifier driver module. The first-level preamplifier starts and, upon reaching the set current value, returns a response command. Upon receiving the response command, the power control module then sends a start command to the second-level preamplifier driver module. The second-level preamplifier starts and, upon reaching the set current value, returns a response command. Upon receiving the response command, the power control module then sends a start command to the main amplifier driver module, thus starting the main amplifier. This sequential loading of current is achieved. Figure 2 As shown, when a driver module malfunctions, it reports the fault information to the power control module, which then sequentially shuts down the main amplifier, secondary preamplifier, and primary preamplifier according to a timing sequence. In the centralized software timing control method, all control relies on a single communication link; if communication is interrupted, the safety mechanism completely fails. When a preceding stage fails, the subsequent stage shutdown relies on software communication, with a response time in milliseconds, causing a delay in the main amplifier's shutdown and potentially damaging the laser. Summary of the Invention

[0005] The purpose of this application is to provide a method and apparatus for safety interlocking of fiber lasers, which can realize the safety interlocking of fiber lasers, improve the fault response speed, and avoid device damage.

[0006] To achieve the above objectives, this application provides the following solution.

[0007] In a first aspect, this application provides a method for safety interlocking of a fiber laser, comprising the following steps.

[0008] When a light output command is received, the first-stage preamplifier in the fiber laser is started. After the current of the first-stage preamplifier reaches the first set current, the second-stage preamplifier and the main amplifier in the fiber laser are started in sequence based on the PWM wave with the set duty cycle and the received response command.

[0009] After the fiber laser is started, the duty cycle of the PWM wave is detected in real time. If the duty cycle of the PWM wave is not equal to the set duty cycle, the main amplifier, secondary preamplifier and primary preamplifier in the fiber laser are turned off in sequence.

[0010] In one embodiment, when a light output command is received, the first-stage preamplifier in the fiber laser is started. After the current of the first-stage preamplifier reaches the set current, the second-stage preamplifier and the main amplifier in the fiber laser are started sequentially based on the PWM wave with the set duty cycle and the received response command. The specific steps include the following.

[0011] When a light output command is received, the first-stage preamplifier in the fiber laser is activated.

[0012] After the current of the first-stage preamplifier reaches the first set current, the first-stage preamplifier drive module is controlled to output a first PWM wave with a set duty cycle to the second-stage preamplifier drive module. At the same time, a second-stage start command is generated according to the response command returned by the first-stage preamplifier drive module. The second-stage preamplifier drive module controls the second-stage preamplifier in the fiber laser to start according to the first PWM wave with a set duty cycle and the second-stage start command, and returns a second PWM wave with a set duty cycle to the first-stage preamplifier drive module.

[0013] After the current of the secondary preamplifier reaches the second set current, the secondary preamplifier drive module is controlled to output a third PWM wave with a set duty cycle to the main amplifier drive module. At the same time, the main amplifier start command is generated according to the response command returned by the secondary preamplifier drive module. The main amplifier drive module controls the main amplifier in the fiber laser to start according to the received third PWM wave with a set duty cycle and the main amplifier start command, and returns a fourth PWM wave with a set duty cycle to the secondary preamplifier drive module.

[0014] In one embodiment, after the fiber laser is started, the duty cycle of the PWM wave is detected in real time. If the duty cycle of the PWM wave is not equal to the set duty cycle, the main amplifier, the secondary preamplifier and the primary preamplifier in the fiber laser are turned off in sequence, specifically including the following steps.

[0015] If the duty cycle of the detected fourth PWM wave is not equal to the set duty cycle, it is determined that the main amplifier driver module has failed. At this time, the control of the secondary preamplifier driver module stops sending the third PWM wave to the main amplifier driver module, all main amplifier driver modules stop working, all main amplifiers are turned off, the main amplifier driver module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier driver module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier driver module, and the primary preamplifier is turned off.

[0016] If the duty cycle of the detected third PWM wave is not equal to the set duty cycle, it is determined that the secondary preamplifier driver module has failed. At this time, all main amplifier driver modules are stopped, all main amplifiers are turned off, the main amplifier driver module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier driver module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier driver module, and the primary preamplifier is turned off.

[0017] If the duty cycle of the detected first PWM wave is not equal to the set duty cycle, it is determined that the first-level preamplifier driver module has failed. At this time, the second-level preamplifier driver module stops sending the third PWM wave to the main amplifier driver module, all main amplifier driver modules stop working, all main amplifiers are turned off, the main amplifier driver module no longer returns the fourth PWM wave with the set duty cycle to the second-level preamplifier driver module, the second-level preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the first-level preamplifier driver module, and the first-level preamplifier is turned off.

[0018] In one embodiment, the first set current is 2A.

[0019] In one embodiment, the second set current is 6A.

[0020] In one embodiment, the first PWM wave, the second PWM wave, the third PWM wave, and the fourth PWM wave have the same set duty cycle.

[0021] In one embodiment, the set duty cycle is 30%.

[0022] Secondly, this application provides a safety interlock device for a fiber laser, comprising: a power control module and a PWM generation and detection circuit; both the power control module and the PWM generation and detection circuit are connected to the fiber laser.

[0023] The PWM generation and detection circuit is used to generate a PWM wave with a set duty cycle.

[0024] The power control module is used to control the first-stage preamplifier in the fiber laser to start when a light output command is received. After the current of the first-stage preamplifier reaches the first set current, it controls the second-stage preamplifier and the main amplifier in the fiber laser to start sequentially based on the PWM wave with a set duty cycle and the received response command.

[0025] The PWM generation and detection circuit is also used to detect the duty cycle of the PWM wave in real time after the fiber laser is started.

[0026] The power control module is also used to sequentially control the main amplifier, secondary preamplifier, and primary preamplifier in the fiber laser to shut down if the duty cycle of the detected PWM wave is not equal to the set duty cycle.

[0027] In one embodiment, the power control module specifically includes: a first-stage preamplifier start-up unit, used to control the first-stage preamplifier in the fiber laser to start when a light output command is received.

[0028] The secondary preamplifier start-up unit is used to control the primary preamplifier drive module to output a first PWM wave with a set duty cycle to the secondary preamplifier drive module after the current of the primary preamplifier reaches a first set current. At the same time, it generates a secondary start-up command according to the response command returned by the primary preamplifier drive module. The secondary preamplifier drive module controls the secondary preamplifier in the fiber laser to start according to the first PWM wave with a set duty cycle and the secondary start-up command, and returns a second PWM wave with a set duty cycle to the primary preamplifier drive module.

[0029] The main preamplifier start-up unit is used to control the secondary preamplifier drive module to output a third PWM wave with a set duty cycle to the main amplifier drive module after the current of the secondary preamplifier reaches the second set current. At the same time, it generates a main amplifier start-up command according to the response command returned by the secondary preamplifier drive module. The main amplifier drive module controls the main amplifier in the fiber laser to start according to the received third PWM wave with a set duty cycle and the main amplifier start-up command, and returns a fourth PWM wave with a set duty cycle to the secondary preamplifier drive module.

[0030] In one embodiment, the power control module further includes: a main amplifier drive fault shutdown unit, used to determine that the main amplifier drive module has malfunctioned if the duty cycle of the detected fourth PWM wave is not equal to the set duty cycle. At this time, the unit controls the secondary preamplifier drive module to stop sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off.

[0031] The secondary drive fault shutdown unit is used to determine that the secondary preamplifier drive module has failed if the duty cycle of the detected third PWM wave is not equal to the set duty cycle. At this time, it controls all main amplifier drive modules to stop working, all main amplifiers are turned off, the main amplifier drive modules no longer return the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off.

[0032] The first-level drive fault shutdown unit is used to determine that the first-level preamplifier drive module has failed if the duty cycle of the detected first PWM wave is not equal to the set duty cycle. At this time, it controls the second-level preamplifier drive module to stop sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the second-level preamplifier drive module, the second-level preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the first-level preamplifier drive module, and the first-level preamplifier is turned off.

[0033] According to the specific embodiments provided in this application, this application has the following technical effects: This application provides a safety interlocking method and apparatus for a fiber laser. When a light output command is received, the first-stage preamplifier in the fiber laser is started. After the current of the first-stage preamplifier reaches a first set current, the second-stage preamplifier and the main amplifier in the fiber laser are started sequentially based on a PWM wave with a set duty cycle and the received response command. The PWM wave and the response command, which are passed forward through the first-stage preamplifier, second-stage preamplifier, and main amplifier in sequence, are used together as an enable signal to realize the coordinated control and start-up of the fiber laser. After the fiber laser is started, the duty cycle of the PWM wave is detected in real time. If the duty cycle of the PWM wave is not equal to the set duty cycle, the main amplifier, secondary preamplifier, and primary preamplifier in the fiber laser are sequentially turned off. The state of the PWM wave transmitted in reverse through the main amplifier, secondary preamplifier, and primary preamplifier is used as an acknowledgment signal to achieve step-by-step shutdown from the later stage to the earlier stage. This application does not require communication conversion through the power control module, realizing the rapid shutdown of the main amplifier. The PWM wave is independent of the software communication system, realizing communication fault immunity and safety interlocking of the fiber laser. The fault shutdown time is shortened from milliseconds (software communication) to microseconds (PWM wave transmission), improving the fault response speed and avoiding device damage. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a flowchart of the light output process control in centralized software timing control.

[0036] Figure 2 This is a flowchart of the control process for the optical switching process in centralized software timing control.

[0037] Figure 3 A flowchart of a fiber laser safety interlocking method provided in an embodiment of this application.

[0038] Figure 4 The flowchart illustrates the control process for adding PWM wave enable transmission in an embodiment of this application.

[0039] Figure 5 This is a flowchart illustrating the control process for the shutdown of the main amplifier driver module when it fails, as provided in an embodiment of this application.

[0040] Figure 6 The flowchart illustrates the control process for the shutdown of the secondary preamplifier driver module when it malfunctions, as provided in this embodiment of the application.

[0041] Figure 7 The flowchart illustrates the control process for the shutdown of the primary preamplifier driver module when it malfunctions, as provided in this embodiment of the application. Detailed Implementation

[0042] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0043] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] In centralized software timing control, when an anomaly occurs in the primary or secondary preamplifier driver module, the subsequent main amplifier driver module needs to be quickly shut down to ensure laser safety. If this is handled via communication, the time delay is in the millisecond range, which can easily damage the laser. Therefore, this application implements a safety interlock for fiber lasers based on PWM wave cascaded control, improving fault response speed and preventing device damage.

[0045] In one exemplary embodiment, such as Figure 3 As shown, a method for safety interlocking of a fiber laser is provided, comprising the following steps.

[0046] Step 101: When a light output command is received, the first-stage preamplifier in the fiber laser is started. After the current of the first-stage preamplifier reaches the first set current, the second-stage preamplifier and the main amplifier in the fiber laser are started in sequence based on the PWM wave with the set duty cycle and the received response command.

[0047] Step 102: After the fiber laser is started, the duty cycle of the PWM wave is detected in real time. If the duty cycle of the PWM wave is not equal to the set duty cycle, the main amplifier, secondary preamplifier and primary preamplifier in the fiber laser are turned off in sequence.

[0048] In one embodiment, step 101 specifically includes the following steps.

[0049] (1) When the light output command is received, the first stage preamplifier in the fiber laser is started.

[0050] (2) After the current of the first-stage preamplifier reaches the first set current, the first-stage preamplifier drive module outputs a first PWM wave (PWM_A wave) with a set duty cycle to the second-stage preamplifier drive module. Simultaneously, it generates a second-stage start command based on the response command received from the first-stage preamplifier drive module. The second-stage preamplifier drive module controls the second-stage preamplifier in the fiber laser to start based on the received first PWM wave with the set duty cycle and the second-stage start command, and returns a second PWM wave (PWM_B wave) with the set duty cycle to the first-stage preamplifier drive module. The value of the first set current is 1A to 3A.

[0051] (3) After the current of the secondary preamplifier reaches the second set current, the secondary preamplifier drive module is controlled to output a third PWM wave (PWM_C wave) with a set duty cycle to the main amplifier drive module. At the same time, a main amplifier start command is generated according to the response command returned by the secondary preamplifier drive module. The main amplifier drive module controls the main amplifier in the fiber laser to start according to the received third PWM wave with a set duty cycle and the main amplifier start command, and returns a fourth PWM wave (PWM_D wave) with a set duty cycle to the secondary preamplifier drive module. The second set current can be exemplarily 6A.

[0052] In one embodiment, step 102 specifically includes the following steps.

[0053] (1) If the duty cycle of the detected fourth PWM wave is not equal to the set duty cycle, it is determined that the main amplifier drive module has failed. At this time, the control of the secondary preamp drive module stops sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamp drive module, the secondary preamp is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamp drive module, and the primary preamp is turned off.

[0054] (2) If the duty cycle of the detected third PWM wave is not equal to the set duty cycle, it is determined that the secondary preamplifier drive module has failed. At this time, all main amplifier drive modules are controlled to stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off.

[0055] (3) If the duty cycle of the detected first PWM wave is not equal to the set duty cycle, it is determined that the first-level preamplifier drive module has failed. At this time, the second-level preamplifier drive module is controlled to stop sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the second-level preamplifier drive module, the second-level preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the first-level preamplifier drive module, and the first-level preamplifier is turned off.

[0056] In another exemplary embodiment of this application, the duty cycles of the first PWM wave, the second PWM wave, the third PWM wave, and the fourth PWM wave are set by the programmer, and the duty cycles of the four PWM waves can be set to the same duty cycle; the duty cycle can be exemplarily 30%. A PWM wave with a duty cycle of 30% is a PWM wave with a correct duty cycle, and a PWM wave with a duty cycle greater than or less than 30% is a PWM wave with an abnormal duty cycle.

[0057] The following is combined with Figures 4-7 The implementation process of the fiber laser safety interlocking method in this embodiment will be described.

[0058] While retaining the existing software timing control, a safety interlock function for PWM wave enable transmission is added. For example... Figure 4As shown, when the current of the first-stage preamplifier reaches the first set value (e.g., 2A), its driver module will output a PWM wave with the correct duty cycle (PWM_A) to the second-stage preamplifier driver module. Upon receiving this PWM wave and a start command from the power control module, the second-stage preamplifier driver module will restart. When the current of the second-stage preamplifier reaches the second set value (e.g., 6A), it will output a PWM wave with the correct duty cycle (PWM_C) to the subsequent main amplifier driver module, and simultaneously return a PWM wave (PWM_B) to the first-stage preamplifier driver module. When the main amplifier driver module receives the PWM_C sent from the second-stage preamplifier driver module and a start command from the power control module, the main amplifier driver module will restart, and simultaneously return a PWM wave (PWM_D) to the second-stage preamplifier driver module. This ensures that the first-stage preamplifier, second-stage preamplifier, and main amplifier are turned on sequentially during startup. Furthermore, if any driver module fails, the subsequent stages can be quickly shut down, such as... Figures 5-7 As shown.

[0059] like Figure 5 As shown, when one of the multiple main amplifier driver modules malfunctions, the duty cycle of the PWM_D wave returned to the secondary preamplifier driver module will be abnormal. After receiving the PWM_D wave with the abnormal duty cycle, the secondary preamplifier driver module determines that the main amplifier driver module has failed. Therefore, the secondary preamplifier driver module will stop sending the PWM_C wave to the main amplifier driver module. When the main amplifier cannot receive the PWM_C wave sent by the secondary preamplifier driver module, all main amplifier driver modules immediately stop working. At this time, the main amplifier driver module will no longer return the PWM_D wave with the correct duty cycle to the secondary preamplifier driver module, the secondary preamplifier is turned off, and it will no longer return the PWM_B wave with the correct duty cycle to the primary preamplifier driver module, the primary preamplifier is turned off.

[0060] like Figure 6 As shown, when the secondary preamplifier driver module malfunctions, the duty cycle of the PWM_C wave sent to the main amplifier driver module will be abnormal. Upon receiving the PWM_C wave with the abnormal duty cycle, all main amplifier driver modules will immediately stop working. At this time, the main amplifier driver module will no longer return the PWM_D wave with the correct duty cycle to the secondary preamplifier driver module, the secondary preamplifier will be turned off, and it will no longer return the PWM_B wave with the correct duty cycle to the primary preamplifier driver module, the primary preamplifier will be turned off.

[0061] like Figure 7As shown, when the primary preamplifier driver module malfunctions, the duty cycle of the PWM_A wave sent to the secondary preamplifier driver module will be abnormal. After receiving the abnormal duty cycle wave, the secondary preamplifier driver module will no longer send the correct duty cycle PWM_C wave to the main amplifier driver module. All main amplifier driver modules will immediately stop working. At this time, the main amplifier driver module will no longer return the correct duty cycle PWM_D wave to the secondary preamplifier driver module, the secondary preamplifier will be turned off, and it will no longer return the correct duty cycle PWM_B wave to the primary preamplifier driver module, the primary preamplifier will be turned off.

[0062] The above process does not require communication conversion through the power control module, thus achieving rapid shutdown of the main amplifier.

[0063] Based on the same inventive concept, this application also provides a fiber laser safety interlocking device for implementing the fiber laser safety interlocking method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of the one or more fiber laser safety interlocking device embodiments provided below can be found in the limitations of the fiber laser safety interlocking method described above, and will not be repeated here.

[0064] In one exemplary embodiment, a safety interlock device for a fiber laser is provided, comprising: a power control module and a PWM generation and detection circuit; both the power control module and the PWM generation and detection circuit are connected to the fiber laser.

[0065] The PWM generation and detection circuit is used to generate a PWM wave with a set duty cycle.

[0066] The power control module is used to control the first-stage preamplifier in the fiber laser to start when a light output command is received. After the current of the first-stage preamplifier reaches the first set current, it controls the second-stage preamplifier and the main amplifier in the fiber laser to start sequentially based on the PWM wave with a set duty cycle and the received response command.

[0067] The PWM generation and detection circuit is also used to detect the duty cycle of the PWM wave in real time after the fiber laser is started.

[0068] The power control module is also used to sequentially control the main amplifier, secondary preamplifier, and primary preamplifier in the fiber laser to shut down if the duty cycle of the detected PWM wave is not equal to the set duty cycle.

[0069] As an optional implementation, the power control module specifically includes: a first-stage preamplifier start-up unit, used to control the first-stage preamplifier in the fiber laser to start when a light output command is received.

[0070] The secondary preamplifier start-up unit is used to control the primary preamplifier drive module to output a first PWM wave with a set duty cycle to the secondary preamplifier drive module after the current of the primary preamplifier reaches a first set current. At the same time, it generates a secondary start-up command according to the response command returned by the primary preamplifier drive module. The secondary preamplifier drive module controls the secondary preamplifier in the fiber laser to start according to the first PWM wave with a set duty cycle and the secondary start-up command, and returns a second PWM wave with a set duty cycle to the primary preamplifier drive module.

[0071] The main preamplifier start-up unit is used to control the secondary preamplifier drive module to output a third PWM wave with a set duty cycle to the main amplifier drive module after the current of the secondary preamplifier reaches the second set current. At the same time, it generates a main amplifier start-up command according to the response command returned by the secondary preamplifier drive module. The main amplifier drive module controls the main amplifier in the fiber laser to start according to the received third PWM wave with a set duty cycle and the main amplifier start-up command, and returns a fourth PWM wave with a set duty cycle to the secondary preamplifier drive module.

[0072] As an optional implementation, the power control module further includes: a main amplifier drive fault shutdown unit, used to determine that the main amplifier drive module has failed if the duty cycle of the detected fourth PWM wave is not equal to the set duty cycle. At this time, the unit controls the secondary preamplifier drive module to stop sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off.

[0073] The secondary drive fault shutdown unit is used to determine that the secondary preamplifier drive module has failed if the duty cycle of the detected third PWM wave is not equal to the set duty cycle. At this time, it controls all main amplifier drive modules to stop working, all main amplifiers are turned off, the main amplifier drive modules no longer return the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off.

[0074] The first-level drive fault shutdown unit is used to determine that the first-level preamplifier drive module has failed if the duty cycle of the detected first PWM wave is not equal to the set duty cycle. At this time, it controls the second-level preamplifier drive module to stop sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the second-level preamplifier drive module, the second-level preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the first-level preamplifier drive module, and the first-level preamplifier is turned off.

[0075] As an optional implementation method, the PWM generation and detection circuit can generate PWM waves in the following three ways: (1) Analog method based on 555 timer: Use 555 timer to form a multivibrator, and adjust the duty cycle by adjusting the potentiometer to change the RC charging and discharging time. (2) Digital method based on microcontroller (such as Arduino, STM32): Use timer module to generate PWM signal, and set the duty cycle through analogWrite() (Arduino) or HAL library (STM32). (3) Generation method of dedicated PWM chip (such as SG3525, TL494): Built-in oscillator, comparator and drive circuit to generate PWM waves with a specific duty cycle.

[0076] In one exemplary embodiment, the fiber laser safety interlocking method can also be implemented using a pure hardware voltage comparison method, such as eliminating software control and directly connecting the front-stage current signal to the rear-stage braking circuit through hardware circuitry. However, this method loses the flexibility of software monitoring and cannot transmit multi-state information.

[0077] The fiber laser safety interlocking method and device of this application are based on a PWM bidirectional transmission topology (forward transmission of PWM wave enable signal (first-stage preamplifier → second-stage preamplifier → main amplifier), and reverse transmission of PWM wave status confirmation signal (main amplifier → second-stage → first-stage)) to achieve coordinated control start-up and independent fault shutdown. The coordinated control logic is as follows: (1) Second-stage preamplifier start-up condition: the enable signal issued by the power control module + the PWM_A wave transmitted from the first-stage preamplifier drive module to the second-stage preamplifier drive module is normal; (2) Main amplifier start-up condition: the enable signal issued by the power control module + the PWM_C wave transmitted from the second-stage preamplifier drive module to the main amplifier drive module is normal. Independent fault shutdown logic: when any drive module of the first-stage preamplifier, second-stage preamplifier, or main amplifier drive module fails, the function of step-by-step shutdown from the rear stage to the front stage is realized through the reverse transmission of PWM wave status confirmation signal.

[0078] The fiber laser safety interlocking method and device of this embodiment have the following advantages: (1) Improved response speed: The fault shutdown time is shortened from millisecond level (software communication) to microsecond level (PWM wave hardware transmission); Communication fault immunity: The PWM hardware link is independent of the software communication system; Cost optimization: No need to change the original software architecture, only the PWM generation / detection circuit needs to be added.

[0079] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for safety interlocking of a fiber laser, characterized in that, include: When a light output command is received, the first-stage preamplifier in the fiber laser is started. After the current of the first-stage preamplifier reaches the first set current, the second-stage preamplifier and the main amplifier in the fiber laser are started in sequence based on the PWM wave with a set duty cycle and the received response command. After the fiber laser is started, the duty cycle of the PWM wave is detected in real time. If the duty cycle of the PWM wave is not equal to the set duty cycle, the main amplifier, secondary preamplifier and primary preamplifier in the fiber laser are turned off in sequence.

2. The fiber laser safety interlocking method according to claim 1, characterized in that, When a light emission command is received, the first-stage preamplifier in the fiber laser is started. After the current of the first-stage preamplifier reaches the set current, the second-stage preamplifier and the main amplifier in the fiber laser are started sequentially based on the PWM wave with a set duty cycle and the received response command. Specifically, this includes: When a light output command is received, the first-stage preamplifier in the fiber laser is activated. After the current of the first-stage preamplifier reaches the first set current, the first-stage preamplifier drive module is controlled to output a first PWM wave with a set duty cycle to the second-stage preamplifier drive module. At the same time, a second-stage start command is generated according to the response command returned by the first-stage preamplifier drive module. The second-stage preamplifier drive module controls the second-stage preamplifier in the fiber laser to start according to the first PWM wave with a set duty cycle and the second-stage start command, and returns a second PWM wave with a set duty cycle to the first-stage preamplifier drive module. After the current of the secondary preamplifier reaches the second set current, the secondary preamplifier drive module is controlled to output a third PWM wave with a set duty cycle to the main amplifier drive module. At the same time, the main amplifier start command is generated according to the response command returned by the secondary preamplifier drive module. The main amplifier drive module controls the main amplifier in the fiber laser to start according to the received third PWM wave with a set duty cycle and the main amplifier start command, and returns a fourth PWM wave with a set duty cycle to the secondary preamplifier drive module.

3. The fiber laser safety interlocking method according to claim 2, characterized in that, After the fiber laser is started, the duty cycle of the PWM wave is monitored in real time. If the duty cycle of the PWM wave is not equal to the set duty cycle, the main amplifier, secondary preamplifier, and primary preamplifier in the fiber laser are sequentially controlled to shut down. Specifically, this includes: If the duty cycle of the detected fourth PWM wave is not equal to the set duty cycle, it is determined that the main amplifier drive module has failed. At this time, the control of the secondary preamplifier drive module stops sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off. If the duty cycle of the detected third PWM wave is not equal to the set duty cycle, it is determined that the secondary preamplifier drive module has failed. At this time, all main amplifier drive modules are stopped, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off. If the duty cycle of the detected first PWM wave is not equal to the set duty cycle, it is determined that the first-level preamplifier driver module has failed. At this time, the second-level preamplifier driver module stops sending the third PWM wave to the main amplifier driver module, all main amplifier driver modules stop working, all main amplifiers are turned off, the main amplifier driver module no longer returns the fourth PWM wave with the set duty cycle to the second-level preamplifier driver module, the second-level preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the first-level preamplifier driver module, and the first-level preamplifier is turned off.

4. The fiber laser safety interlocking method according to claim 2, characterized in that, The first set current is 2A.

5. The fiber laser safety interlocking method according to claim 2, characterized in that, The second set current is 6A.

6. The fiber laser safety interlocking method according to claim 2, characterized in that, The first PWM wave, the second PWM wave, the third PWM wave, and the fourth PWM wave have the same set duty cycle.

7. The fiber laser safety interlocking method according to claim 6, characterized in that, The duty cycle is set to 30%.

8. A safety interlock device for a fiber laser, characterized in that, include: A power control module and a PWM generation and detection circuit are included; both the power control module and the PWM generation and detection circuit are connected to a fiber laser. The PWM generation and detection circuit is used to generate a PWM wave with a set duty cycle; The power control module is used to control the first-stage preamplifier in the fiber laser to start when a light output command is received. After the current of the first-stage preamplifier reaches the first set current, it controls the second-stage preamplifier and the main amplifier in the fiber laser to start sequentially based on the PWM wave with a set duty cycle and the received response command. The PWM generation and detection circuit is also used to detect the duty cycle of the PWM wave in real time after the fiber laser is started. The power control module is also used to sequentially control the main amplifier, secondary preamplifier, and primary preamplifier in the fiber laser to shut down if the duty cycle of the detected PWM wave is not equal to the set duty cycle.

9. The fiber laser safety interlock device according to claim 8, characterized in that, The power control module specifically includes: The first-stage preamplifier start-up unit is used to control the start-up of the first-stage preamplifier in the fiber laser when a light output command is received. The secondary preamplifier start-up unit is used to control the primary preamplifier drive module to output a first PWM wave with a set duty cycle to the secondary preamplifier drive module after the current of the primary preamplifier reaches a first set current. At the same time, it generates a secondary start-up command according to the response command returned by the primary preamplifier drive module. The secondary preamplifier drive module controls the secondary preamplifier in the fiber laser to start according to the first PWM wave with a set duty cycle and the secondary start-up command, and returns a second PWM wave with a set duty cycle to the primary preamplifier drive module. The main preamplifier start-up unit is used to control the secondary preamplifier drive module to output a third PWM wave with a set duty cycle to the main amplifier drive module after the current of the secondary preamplifier reaches the second set current. At the same time, it generates a main amplifier start-up command according to the response command returned by the secondary preamplifier drive module. The main amplifier drive module controls the main amplifier in the fiber laser to start according to the received third PWM wave with a set duty cycle and the main amplifier start-up command, and returns a fourth PWM wave with a set duty cycle to the secondary preamplifier drive module.

10. The fiber laser safety interlock device according to claim 9, characterized in that, The power control module further includes: The main amplifier drive fault shutdown unit is used to determine that the main amplifier drive module has failed if the duty cycle of the detected fourth PWM wave is not equal to the set duty cycle. At this time, the secondary preamplifier drive module is controlled to stop sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off. The secondary drive fault shutdown unit is used to determine that the secondary preamplifier drive module has failed if the duty cycle of the detected third PWM wave is not equal to the set duty cycle. At this time, it controls all main amplifier drive modules to stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the secondary preamplifier drive module, the secondary preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the primary preamplifier drive module, and the primary preamplifier is turned off. The first-level drive fault shutdown unit is used to determine that the first-level preamplifier drive module has failed if the duty cycle of the detected first PWM wave is not equal to the set duty cycle. At this time, it controls the second-level preamplifier drive module to stop sending the third PWM wave to the main amplifier drive module, all main amplifier drive modules stop working, all main amplifiers are turned off, the main amplifier drive module no longer returns the fourth PWM wave with the set duty cycle to the second-level preamplifier drive module, the second-level preamplifier is turned off and no longer returns the second PWM wave with the set duty cycle to the first-level preamplifier drive module, and the first-level preamplifier is turned off.

Images