Intrinsic safety circuit control method based on software and hardware cooperative current limiting

Abstract

The invention discloses an intrinsically safe circuit control method based on software and hardware cooperative current limiting, and particularly relates to the technical field of intrinsically safe circuit control. Collecting transient current, temperature, a load state code and a communication period, and constructing a state vector; performing risk assessment on the state vector through a current limiting judgment model, and identifying whether a potential over-limit working condition exists or not; if the current exceeds the limit, matching an optimal hardware current-limiting path and starting a current-limiting device, dynamically adjusting a power supply period and a communication window according to current-limiting intensity and load characteristics, and generating and issuing a regulation and control instruction; the feedback current is compared with a safety threshold value, and whether the current limiting state is quitted or the regulation and control process is re-entered is judged; if the number of continuous current limiting failures exceeds the preset number of times, early warning is triggered, and a safe locking state is entered; according to the invention, intelligent current-limiting control and closed-loop adjustment of the intrinsically safe circuit are realized, and the intrinsic safety, response sensitivity and operation stability of the system are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intrinsic safety circuit control, and particularly relates to an intrinsic safety circuit control method based on software and hardware collaborative current limiting. BACKGROUND

[0002] An intrinsic safety circuit is a widely used safety protection measure in explosion-proof electrical systems, and its core goal is to ensure that the voltage and current in the circuit do not exceed the critical value of igniting dangerous gas or dust under any fault condition. However, with the development of intelligent, small, and wireless intrinsic safety devices, the traditional intrinsic safety circuit relying only on hardware current limiting (such as current limiting resistors, Zener diodes, etc.) has been difficult to meet the safety control requirements in complex and dynamic power consumption scenarios. For example, in a wireless sensor network in a coal mine, a sensor node needs to upload multiple parameter data in a short time, and such peak communication behavior may cause a short-time current to exceed the limit. However, the traditional static hardware current limiting cannot dynamically adjust the power supply capability, resulting in limited system performance and even triggering false power-off protection. At the same time, if a simple software current limiting strategy such as timed shutdown or data retransmission is used, it cannot accurately control the transient current and may cause data loss or node disconnection, affecting the overall safety monitoring effect. SUMMARY

[0003] The purpose of the present application is to provide an intrinsic safety circuit control method based on software and hardware collaborative current limiting to solve the problems in the background art.

[0004] To achieve the above purpose, the present application provides the following technical solution: an intrinsic safety circuit control method based on software and hardware collaborative current limiting, comprising: S100: Collecting real-time working parameters on the load side of the intrinsic safety circuit, including transient current It, temperature T, load state code Lc, and communication period P, and generating a state vector Vs={It, T, Lc, P}; S200: According to the state vector Vs, calling a current limiting judgment model to identify whether the current state belongs to a potential over-limit working condition, and if so, proceeding to step S300, otherwise maintaining the current power supply state; S300: Based on the eigenvalue of the over-limit working condition, matching the optimal current limiting path R from the hardware current limiting strategy set H={R1, R2,..., Rn}, and sending a control signal to make the circuit enter the hardware current limiting mode; S400: Starting a software regulation module, dynamically adjusting the power supply period and communication window time according to the state vector Vs at the last moment and the current current limiting path R, and generating a regulation instruction; S500: Sending the regulation instruction to the main control chip to trigger the power supply module to enter the dynamic current limiting state, and recording the current state log; S600: Monitor the current feedback value If after current limiting execution, if If≤Isafe, exit the current limiting mode and restore normal power supply; if If>Isafe, update the state vector Vs, Isafe is the current safety threshold, repeat steps S200 to S500; S700: When three or more dynamic current limiting states occur in succession, a warning signal is generated at this time, and a safety locking state is entered.

[0005] Preferably, the current limiting judgment model is called according to the state vector Vs, and it is identified whether the current state belongs to a potential over-limit working condition, comprising: S210: Normalizing the transient current, temperature, load state code and communication cycle in the state vector Vs to generate a standardized state vector ; S220: Inputting the standardized state vector into a pre-constructed current limiting judgment model, the current limiting judgment model based on multi-threshold decision rules and state-related weight parameters, comprehensively evaluating each state parameter to obtain a corresponding risk evaluation value Rv; S230: Comparing the risk evaluation value Rv with a preset over-limit risk threshold to judge whether the current running state meets the judgment condition of the potential over-limit working condition; S240: When the risk evaluation value Rv exceeds the over-limit risk threshold, an over-limit judgment flag is generated, and step S300 is entered, otherwise the current power supply state is maintained.

[0006] Preferably, the optimal current limiting path R is matched, comprising: S310: Based on the risk evaluation value and the standardized state vector, extracting a characteristic value combination of the over-limit working condition, including current over-limit amplitude, temperature rise rate, load level weight and communication frequency level; S320: Comparing the characteristic value combination with a preset current limiting path matching rule to calculate the matching score of each hardware current limiting path and the characteristic value; S330: According to the matching score, the hardware current limiting path with the highest score in the current limiting strategy set is screened to determine the optimal current limiting path under the current working condition; S340: The current limiting component corresponding to the optimal current limiting path is activated.

[0007] Preferably, the power supply cycle and the communication window time are dynamically adjusted according to the state vector Vs of the last moment and the current limiting path R, comprising: S410: Extracting the load level weight and the communication frequency level in the standardized state vector of the last moment; S420: Combining the current limiting intensity parameter of the current limiting path, calculating the target power supply cycle adjustment coefficient and the communication window compression ratio; S430: Dynamically generate new power supply cycle and communication time window parameters based on the adjustment coefficient, and record as the regulation instruction parameter set.

[0008] Preferably, the target power supply cycle adjustment coefficient is calculated based on the current current limiting path strength parameter, comprising: S421: Read the current limiting strength parameter corresponding to the activated current limiting path; S422: Compare the current limiting strength parameter with the current over-limit amplitude in the state vector at the last moment to obtain the current reduction demand value; S423: Calculate the power supply cycle adjustment coefficient based on the matching degree between the current reduction demand value and the current limiting strength.

[0009] Preferably, the power supply cycle adjustment coefficient = 1 + (current reduction demand value ÷ current limiting strength) × K1; wherein K1 is a regulation proportion constant, the current reduction demand value is the difference between the current value and the maximum carrying current of the current limiting path, and the current limiting strength is the ratio of the maximum carrying current of the current limiting path to the current actual load current.

[0010] Preferably, the current safety threshold is a safety current upper limit value.

[0011] Preferably, the S300 further comprises: the hardware current limiting path comprises a silicon controlled current limiting device, a digital resistance network or a variable inductance element, and the master control chip activates the corresponding element of the selected current limiting path to enter the working state by outputting a control signal.

[0012] In the above technical solution, the present application provides technical effects and advantages: 1. The present application realizes real-time identification and dynamic response of transient over-limit risk in intrinsically safe circuit by constructing a software and hardware cooperative current limiting control mechanism. Compared with the traditional method of relying on fixed hardware current limiting devices, the present application introduces a multi-parameter state vector, a risk assessment model and a current limiting path matching algorithm, so that the current limiting strategy can accurately select according to the comprehensive state of the current load, current, temperature and communication behavior, and further optimize the power supply cycle and communication window through software regulation means, significantly improving the current limiting accuracy and energy utilization efficiency of the system under complex dynamic working conditions.

[0013] 2. The present application also introduces a current feedback closed-loop control mechanism and a continuous current limiting frequency determination logic, which has self-adaptive adjustment capability and abnormal locking function, ensuring that it automatically enters a safe protection state in the case of continuous current limiting failure or uncontrollable load impact. Through the above technical solution, the present application not only enhances the active safety protection capability of the intrinsically safe circuit in high-risk scenarios, but also considers the operation stability and functional continuity, and has good industrial application value. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0015] Figure 1 The method flowchart of the present application. DETAILED DESCRIPTION

[0016] In order to make the purposes, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0017] Embodiment, please refer to Figure 1 As shown in the figure, the safety circuit control method based on software and hardware cooperative current limiting described in the embodiment comprises: S100: Collecting real-time working parameters of the safety circuit load side, including transient current It, temperature T, load state code Lc and communication cycle P, generating state vector Vs={It, T, Lc, P}.

[0018] Transient current It: Collected by the current detection unit, and capturing the current peak value at the time of communication burst or load start; Temperature T: Collected by the temperature sensing unit close to the power device, obtaining the working temperature of the load nearby environment or device surface; Load state code Lc: Automatically generated by the state recognition unit according to the current working mode of the load, for example, 0 can be set to represent the idle state, 1 to represent the standby mode, 2 to represent the data communication, 3 to represent the sensor sampling, and 4 to represent the high power impact state; Communication cycle P: Recording the communication activity cycle information of the load end by the communication management unit, calculating the data upload interval in the past period.

[0019] The above parameters are uniformly collected and packaged into state vector Vs={It, T, Lc, P}. It should be noted that the collection period of state vector Vs can be configured to 10 ms-100 ms, which is set according to the trade-off demand of reaction speed and power consumption control of target application.

[0020] For example, assume that the intrinsically safe device is a downhole multi-parameter sensor node, which is currently in the process of uploading data, and the collected state parameters are as follows: It=215mA (exceeding the static current limiting threshold); T=48.5℃ (in the high temperature critical zone); Lc=2 (communication); P=350ms (high frequency communication); According to the above data, a state vector is generated: Vs={215, 48.5, 2, 350}; the state vector indicates that the current node is in a high-risk short-time overcurrent state, providing data support for subsequent current limiting decisions.

[0021] S200: According to the state vector Vs, call the current limiting judgment model to identify whether the current state belongs to a potential over-limit working condition, if yes, go to step S300, otherwise maintain the current power supply state.

[0022] Step S210: The obtained state vector consists of four parameters, including transient current, circuit temperature, load state code and communication period. Since the physical units of each parameter are different, direct use may lead to unbalanced model evaluation results. Therefore, first, normalize the four parameters respectively, the specific operation is as follows: For transient current, divide it by the maximum safe current allowed by the intrinsically safe circuit to obtain the normalized current value; For the temperature parameter, subtract the minimum allowable temperature in the circuit working environment from the measured temperature and divide by the maximum temperature difference range to obtain the normalized temperature value; For the load state code, according to the pre-defined state level of the actual working condition, map each state to a risk factor in the range of 0 to 1; For the communication period, use the normalization method to convert high frequency communication to high risk weight and low frequency communication to low weight.

[0023] The final standardized state vector is represented as: Standardized state vector={normalized current, normalized temperature, normalized load level, normalized communication period}.

[0024] Step S220: The standardized state vector is input into the current limiting judgment model for comprehensive risk assessment. The current limiting judgment model is constructed using a multi-threshold scoring mechanism with hierarchical weight superposition, as follows: First, assign weight coefficients to the four standardized parameters, respectively, as current weight, temperature weight, load level weight and communication period weight. These weights are determined through a large number of experimental samples and reflect the influence of different parameters on the over-limit risk of the circuit; Then, use linear weighting algorithm to combine each parameter to calculate the total risk assessment value: Risk assessment value = (current normalized value x current weight) + (temperature normalized value x temperature weight) + (load level normalized value x load weight) + (communication cycle normalized value x communication weight); For example, in an actual working condition, the current weight is set to 0.4, the temperature weight is 0.3, the load level weight is 0.2, and the communication cycle weight is 0.1, indicating that the current and temperature are the main current limiting judgment indicators.

[0025] The model is trained by an experimental data set before actual use, and the weight coefficients are optimized in a manner combining manual setting and dynamic calibration, so that the risk assessment value has high recognition rate and low misjudgment rate in actual working conditions.

[0026] Step S230: After the risk assessment value is calculated, the assessment value is compared with a preset over-limit risk threshold. The over-limit risk threshold is determined according to the maximum power bearing capacity of the intrinsic safety circuit specific product, and is usually a fixed value in the range of 0 to 1. For example, for an application scenario with a medium-intensity protection level as the maximum safety design requirement of the circuit, the risk threshold can be set to 0.7. When the risk assessment value is greater than 0.7, it is considered to have entered a potential over-limit working condition interval.

[0027] Step S240: If the risk assessment value calculated at present exceeds the over-limit risk threshold, an over-limit judgment flag with a logic of "true" is generated, and the flag is output as a signal to a subsequent control process, and the combination control of the hardware current limiting path selection and the software adjustment strategy is started, that is, step S300 is entered.

[0028] If the risk assessment value is lower than the risk threshold, it indicates that the current load state is within the safe range, and the method of the present application will maintain the current power supply strategy and does not intervene in the circuit, thereby ensuring energy efficiency and operation continuity.

[0029] S300: Based on the characteristic value of the over-limit working condition, the optimal current limiting path R is matched from the hardware current limiting strategy set H = {R1, R2,..., Rn}, and a control signal is sent to make the circuit enter the hardware current limiting mode.

[0030] Step S310: First, the key risk characteristic parameters of the current working condition are extracted according to the calculated risk assessment value and the standardized state vector, to form a characteristic value combination, which is used as the input basis for matching the current limiting path. The characteristic value combination includes the following four items: Current over-limit amplitude: refers to the ratio of the difference between the actual transient current and the intrinsic safety maximum safe current to the safe current, used to evaluate the current overload degree; Temperature rise rate: calculated according to the temperature change in two consecutive sampling periods divided by the sampling interval time, used to reflect the instantaneous heating trend of the circuit; Load level weight: according to the normalized load state parameter, the risk level is correspondingly obtained by table lookup, for example, high impact load is assigned a weight value of 0.8, standby state is assigned a value of 0.1; Communication frequency level: map the communication period parameter to a level value, the shorter the communication interval, the higher the level, which is used to evaluate the impact of instantaneous communication behavior on the load.

[0031] Finally, the above four items form a feature value combination, denoted as: working condition feature value combination = {current overrun amplitude, temperature rise rate, load level weight, communication frequency level}.

[0032] Step S320: In this step, the feature value combination is compared with the strategy templates corresponding to a plurality of hardware current limiting paths to calculate the adaptation degree of each current limiting path under the current working condition. The specific method is as follows: A set of reference feature vectors are preset for each hardware current limiting path, representing the typical over-limit scenarios applicable to it; The similarity between the current working condition feature value combination and each reference feature vector is calculated using the weighted Euclidean distance method; A weight coefficient is assigned to each feature, for example, the current overrun amplitude weight is 0.4, the temperature rise rate weight is 0.3, the load level weight is 0.2, and the communication frequency level weight is 0.1; The matching score is calculated according to the reciprocal of the distance, and the higher the matching score, the more suitable the current limiting path is for the current working condition.

[0033] The score calculation result is stored in the form of a two-dimensional array for subsequent filtering.

[0034] Step S330: According to the matching score array obtained in step S320, the highest score is selected from all current limiting paths to determine the optimal hardware current limiting path under the current working condition. The selection rule is: The matching score must be greater than the set minimum adaptation threshold, for example, set to 0.6, if no path score is higher than the threshold, it is determined that there is no adaptive path; If there are multiple current limiting paths with the same score and the highest value, the one with shorter current limiting response time is preferred to improve response speed; The selected current limiting path number is recorded for subsequent control call.

[0035] For example, in the current limiting strategy set, there are three current limiting paths, and the corresponding scores are 0.45, 0.73 and 0.69 respectively, then path two is the optimal path under the current working condition.

[0036] Step S340: After determining the optimal current limiting path, the corresponding current limiting component is driven into working state by control signal to implement physical current limiting. The current limiting component can include thyristor, switch resistance network, variable inductance or power semiconductor element, etc. The specific operation includes: The main controller outputs a control signal to open the path where the current limiting component is located; The current limiting component enters working state according to the designed current limiting characteristics (such as rated resistance, current cutoff point) to limit the current not to exceed the upper limit of intrinsic safety; At the same time, record the current limiting path calling time and response result for feedback to the subsequent dynamic evaluation module for model correction.

[0037] This step ensures the pertinence and dynamic response of the hardware current limiting strategy, and provides a hardware safety basis for the subsequent software regulation step.

[0038] S400: Start the software regulation module, and dynamically adjust the power supply period and communication window time according to the state vector Vs at the last moment and the current current limiting path R to generate regulation instructions.

[0039] Step S410: In the standardized state vector generated in step S210, the normalized load level weight and communication period parameter are included. This step extracts two items for subsequent regulation calculation: Load level weight: represents the influence degree of the current load running state on power demand, the value range is 0 to 1, the larger the value, the more intense the load behavior; Communication frequency level: through the normalization processing of the communication period, it is inversely mapped to the communication frequency level, the larger the value, the more frequent the device communication and the more concentrated the instantaneous power consumption.

[0040] These two parameters reflect the "behavior intensity" of the circuit in the previous period, which is used to judge the acceptable running density under the current current limiting.

[0041] Step S420: The goal of this step is to determine the power supply period that can be appropriately extended and the communication time window that can be shortened through supply-demand comparison calculation to reduce the power density per unit time. This step is divided into the following three sub-steps: Step S421: The current limiting path activated by step S340 has a definite current limiting capability, and its current limiting intensity parameter is composed of the following three indexes: Maximum carrying current (unit: mA): determined by the rated index of the current limiting device; Voltage drop tolerance (unit: V): refers to the maximum voltage loss allowed by the circuit under current limiting state; Response time (unit: ms): represents the time delay from current limiting start to current limiting effect taking effect.

[0042] The current limiting strength parameter can be preset by experiment or calculated from device performance data, and written into the parameter table of each path in the design stage.

[0043] Step S422: This step is used to quantify the degree of current load exceeding the current limiting capacity. The specific process is as follows: Extract the transient current normalization value from the normalized state vector at the last moment; convert the normalization value to the actual current value; calculate the difference between the current value and the maximum carrying current of the current limiting path, which is the current reduction demand value. If the value is positive, it means that the current power consumption is over limit, and the energy output per unit time needs to be reduced by prolonging the power supply cycle and compressing the communication time.

[0044] Step S423: According to the ratio between the "current reduction demand value" and the "current limiting strength", a power supply cycle adjustment coefficient is generated, and the specific method is as follows: The current limiting strength is the ratio of the maximum carrying current of the current limiting path to the current actual load current; Then use the linear model to calculate the adjustment coefficient: power supply cycle adjustment coefficient = 1 + (current reduction demand value ÷ current limiting strength) × K1; where K1 is the adjustment proportion constant, usually set to 0.5-1.5, used to control the adjustment speed and amplitude. If the adjustment coefficient exceeds the upper limit of the maximum safe power supply cycle, it is limited to ensure the stability of power supply.

[0045] Step S430: According to the calculated power supply cycle adjustment coefficient, the following operations are completed: Multiply the original power supply cycle by the adjustment coefficient to get the new target power supply cycle; At the same time, according to the load level weight and the communication frequency level, multiply by the compression proportion coefficient to get the new communication window length; The above two parameters are packaged into a structured control instruction parameter set, which includes fields such as "target power supply cycle value", "communication window start and end time", "effective duration", "overload response flag", etc. The parameter set will be sent to the power supply control unit and communication scheduling unit of the control core in step S440 to complete the soft adjustment action.

[0046] S500: The control instruction is issued to the main control chip to trigger the power supply module to enter the dynamic current limiting state, and the current state log is recorded.

[0047] The control instruction in this step includes two main parts: target power supply cycle value and communication window parameter set, which are packaged into a structured control instruction and denoted as control instruction set Cs. The instruction set contains the following fields: Target power supply cycle: unit is millisecond, representing the minimum interval between two power supply cycles; Communication window start time and duration: used to set the time period for the master chip to open data transmission; Adjustment mode flag: used to identify whether in dynamic current limiting state; Security check field: used to check the integrity of the data packet to prevent false triggering of control commands.

[0048] The master chip receives the control instruction set Cs through the interrupt receiving mechanism or the timing scheduler, and once the receiving is completed and the security check is passed, it enters the dynamic current limiting control process.

[0049] The master chip reconfigures the internal power supply clock register according to the target power supply period in the control instruction, controls the power supply switch tube or voltage stabilizer to be periodically turned on and off within the specified time sequence, so as to reduce the energy consumption per unit time.

[0050] At the same time, the communication interface limits data transmission only within the specified time period according to the communication window parameters, avoiding the generation of burst communication behavior in the current limiting state to cause current peak value.

[0051] If the current limiting component is a programmable current limiting device (such as a thyristor or a digital resistance array), the master chip will also control its resistance value position through the output level signal, forming a current management process jointly participated by hardware and software.

[0052] In order to realize the traceability of the running state, the master chip records the current execution state as a state log after completing the execution of the control instruction, which is recorded as the log data set Ls, including: the current power supply period value; the current communication window parameters; the current current limiting path number; the actual feedback current value and temperature value; the control instruction receiving time stamp and execution state; the flag indicating whether to enter the current limiting protection state.

[0053] The log data set Ls is stored in the built-in non-volatile storage area of the master chip, or is sent in real time to the external monitoring device through the serial port, which is used for system evaluation and safety audit.

[0054] S600: Monitor the current feedback value If after current limiting execution, if If≤Isafe, exit the current limiting mode and restore normal power supply; if If>Isafe, update the state vector Vs, Isafe is the current safety threshold, repeat steps S200 to S500.

[0055] Continuous current sampling is performed on the power supply circuit. In order to ensure the stability and responsiveness of the data, the sampling frequency is set to no less than 1000 times per second, and short-time sliding average filtering processing is performed to obtain the current transient current feedback value, which is recorded as the current feedback value If.

[0056] The current feedback value If is compared with a preset upper limit value of safety current, denoted as safety threshold Isafe, which is set according to the intrinsic safety certification requirements of the circuit and the carrying capacity of the current limiting device, and the unit is milliampere. For example, in a certain implementation environment, Isafe can be set to 180 milliampere. The judgment condition is as follows: if the current feedback value If is less than or equal to the safety threshold Isafe, it means that the current limiting control measure achieves the expected goal; if the current feedback value If is still higher than the safety threshold Isafe, it means that the current limiting effect of this round is insufficient, which may be caused by the rapid change of the load or the insufficient response of the current limiting path.

[0057] If the current feedback value If meets the condition If≤Isafe, the master control chip immediately generates a current limiting exit flag and performs the following operations: Clear the control signal of the current limiting path and close the current limiting device path; Restore the normal power supply cycle and communication window parameters before current limiting; Record the "current limiting end" event in the state log, including the timestamp, current recovery value and recovery method; Enter the normal working state and continue to schedule communication and load operation according to the original plan.

[0058] This process ensures that the current limiting state is exited in time without affecting the stability of the system, avoiding resource waste or function degradation.

[0059] If the current feedback value If exceeds the safety threshold Isafe, the master control chip will determine that the current limiting control fails this round and start the current limiting re-entry process: Recollect the current current, temperature, load level and communication cycle to build an updated state vector Vsnew; Enter the current limiting judgment process of step S200 again with the updated state vector as input; According to the order of steps S200 to S500, repeat the judgment, path selection, control instruction generation and execution process until the current feedback value is stable below the safety threshold.

[0060] The re-entry mechanism ensures that the system has sustained adjustment capability in the dynamic load change scenario, forms a closed-loop current limiting control logic, and improves the operation stability and safety response capability of the intrinsically safe circuit.

[0061] S700: When three or more dynamic current limiting states occur continuously, a warning signal is generated at this time, and the system enters a safety locking state.

[0062] The main control chip is internally provided with a dynamic current-limiting trigger counter for recording the number of times of triggering the current-limiting control process in succession. When the system re-enters step S200 and completes the complete S200 to S500 control process, if it still needs to enter the next round of current-limiting control, the value of the counter is automatically increased by 1. Initially, the counter value is 0; if the system is restored to the normal power supply state in the middle, the counter is automatically cleared; only when the continuous judgment, current-limiting, and regulation are more than three times, and the current-limiting state is not successfully exited between each time, the counter will continue to accumulate.

[0063] When it is detected that the number of times of continuous dynamic current-limiting reaches a preset threshold, for example, the threshold is set to 3 times, the main control chip will determine that the current device has a persistent load abnormality or a risk state that cannot be current-limited, and immediately perform the following operations: Generate a set of structured warning data packets, including the number of current-limiting triggers, the history record of current feedback values, the current state vector, and the trigger timestamp; Send a warning signal to the upper device or the remote monitoring platform through the communication interface; Trigger an audible and visual alarm, a status light blinking, or a display screen warning information on the device locally, to prompt the user that the current device has an intrinsic safety operation risk.

[0064] The format of the warning signal meets the requirements of the industrial field safety communication protocol, ensuring compatibility with existing monitoring systems.

[0065] To ensure safe operation of the device, the device immediately enters a safety-locked state after generating the warning signal, and the processing method is as follows: Stop the power supply output of the main control chip to the load side, and disconnect all power supply channels; Synchronously disable the communication function and the sensing function, and enter the lowest power consumption sleep mode; Lock the current state vector and the current-limiting record, and write them into the non-volatile memory for subsequent reset or maintenance; Only allow exiting the locked state through a physical reset button, an authorized remote instruction, or an upper computer safety unlocking instruction.

[0066] The locked state is an automatic exit state, which must be completed by an authorized maintenance process to ensure that the device will not resume operation before the potential fault is resolved.

[0067] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for controlling intrinsically safe circuits based on hardware and software collaborative current limiting, characterized in that: include: S100: Collects real-time operating parameters of the intrinsically safe circuit load side, including transient current It, temperature T, load status code Lc and communication cycle P, and generates a status vector Vs={It,T,Lc,P}. S200: Based on the state vector Vs, call the current limiting judgment model to identify whether the current state belongs to a potential over-limit condition. If so, proceed to step S300; otherwise, maintain the current power supply state. S300: Based on the characteristic value of the over-limit operating condition, the optimal current limiting path R is matched from the set of hardware current limiting strategies H={R1,R2,...,Rn}, and a control signal is sent to make the circuit enter the hardware current limiting mode; S400: Start the software control module, dynamically adjust the power supply cycle and communication window time according to the state vector Vs of the previous moment and the current current limiting path R, and generate control commands; S500: The control command is sent to the main control chip to trigger the power supply module to enter the dynamic current limiting state and record the current status log; S600: Monitor the current feedback value If after the current limiting is executed. If ≤ Isafe, exit the current limiting mode and restore normal power supply. If > Isafe, update the state vector Vs, where Isafe is the current safety threshold. Repeat steps S200 to S500. S700: When dynamic current limiting occurs three or more times consecutively, a warning signal is generated and the system enters a safety lockout state.

2. The intrinsically safe circuit control method based on hardware and software collaborative current limiting according to claim 1, characterized in that: The step of calling the current limiting judgment model based on the state vector Vs to identify whether the current state belongs to a potential over-limit condition includes: S210: Normalize the transient current, temperature, load status code, and communication cycle in the state vector Vs to generate a standardized state vector. ; S220: Standardize the state vector Input a pre-built rate limiting judgment model. The rate limiting judgment model is based on multi-threshold judgment rules and state-related weight parameters to comprehensively evaluate each state parameter and obtain the corresponding risk assessment value Rv. S230: Compare the risk assessment value Rv with the preset over-limit risk threshold to determine whether the current operating status meets the judgment conditions for potential over-limit conditions. S240: When the risk assessment value Rv exceeds the over-limit risk threshold, an over-limit judgment flag is generated and the process proceeds to step S300; otherwise, the current power supply status is maintained.

3. The intrinsically safe circuit control method based on hardware and software collaborative current limiting according to claim 1, characterized in that: The matching of the optimal rate-limiting path R includes: S310: Based on risk assessment values ​​and standardized state vectors, extract feature value combinations of over-limit operating conditions, including current over-limit amplitude, temperature rise rate, load level weight, and communication frequency level; S320: Compare the combination of feature values ​​with the preset current limiting path matching rules, and calculate the matching score between each hardware current limiting path and the feature value. S330: Based on the matching score, select the hardware current limiting path with the highest score from the set of current limiting strategies and determine it as the optimal current limiting path under the current operating conditions. S340: Activate the rate limiting component corresponding to the optimal rate limiting path.

4. The intrinsically safe circuit control method based on hardware and software collaborative current limiting according to claim 1, characterized in that: The step of dynamically adjusting the power supply cycle and communication window time based on the previous state vector Vs and the current current limiting path R includes: S410: Extract the load level weight and communication frequency level from the standardized state vector of the previous time step; S420: Calculate the target power supply cycle adjustment coefficient and communication window compression ratio by combining the current current limiting intensity parameters of the current current limiting path; S430: Dynamically generate new power supply cycle and communication time window parameters based on the adjustment coefficient, and record them as a set of control command parameters.

5. The intrinsically safe circuit control method based on hardware and software collaborative current limiting according to claim 4, characterized in that: The calculation of the target power supply cycle adjustment coefficient, based on the current limiting intensity parameters of the current limiting path, includes: S421: Read the current rate limiting strength parameters corresponding to the currently activated rate limiting path; S422: Compare the current limiting intensity parameter with the current over-limit magnitude in the state vector of the previous moment to obtain the current reduction requirement value; S423: Calculate the power supply cycle adjustment coefficient based on the degree of matching between the current reduction demand value and the current limiting intensity.

6. The intrinsically safe circuit control method based on hardware and software collaborative current limiting according to claim 5, characterized in that: The power supply cycle adjustment coefficient = 1 + (current reduction demand value ÷ current limiting intensity) × K1; where K1 is the adjustment ratio constant, the current reduction demand value is the difference between the current value and the maximum carrying current of the current limiting path, and the current limiting intensity is the ratio of the maximum carrying current of the current limiting path to the current actual load current.

7. The intrinsically safe circuit control method based on hardware and software collaborative current limiting according to claim 1, characterized in that: The current safety threshold is the upper limit of the safe current.

8. The intrinsically safe circuit control method based on hardware and software collaborative current limiting according to claim 1, characterized in that: The S300 further includes: the hardware current limiting path includes a silicon controlled rectifier current limiting device, a digital resistor network or a variable inductor element, and the main control chip activates the corresponding element of the selected current limiting path by outputting a control signal to put it into working state.

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