Industrial computer self-protection method and circuit

Abstract

The application relates to the technical field of industrial automation control, in particular to an industrial personal computer self-protection method and circuit, which comprises the following steps: after the industrial personal computer is powered on, a reference voltage constant is acquired, a state sampling voltage related to the input voltage is collected based on a preset sampling rule; the system working state of the industrial personal computer is determined based on the state sampling voltage and the reference voltage constant; a driving signal is generated based on the system working state, wherein the driving signal at least comprises an off driving signal and an on driving signal, and the driving signal is used for driving the off or on of a power source path power switching element connected to the input voltage and a rear-end load circuit. The application has the effect of improving the protection capability of the industrial personal computer itself against power supply voltage abnormalities.

Description

Technical Field

[0001] This application relates to the field of industrial automation control technology, and in particular to a self-protection method and circuit for an industrial control computer. Background Technology

[0002] Currently, industrial control computers (ICCs), as the core of industrial production automation systems, are widely deployed in various complex industrial environments. In these environments, the stability of the power grid is often affected by the frequent start-stop of high-power inductive loads such as motors and frequency converters, resulting in transient disturbances such as voltage spikes (overvoltage) and voltage drops (undervoltage) on the power supply lines of ICCs.

[0003] Existing industrial PC power supply designs typically integrate basic filtering and voltage regulation units, but their protection against severe voltage fluctuations exceeding normal operating ranges is often insufficient. Once voltage spikes exceed the withstand voltage limits of internal precision electronic components such as the CPU and memory, or voltage drops cause logic circuit malfunctions, permanent hardware damage or system crashes can easily occur, leading to significant production interruptions and economic losses. To address this issue, the industry often adds expensive external power protection devices such as UPS and dedicated power purifiers. This not only increases overall deployment costs and space requirements but also complicates the system structure and increases potential failure points, thus leaving room for improvement. Summary of the Invention

[0004] To improve the protection capability of industrial control computers against abnormal power supply voltage, this application provides a self-protection method and circuit for industrial control computers.

[0005] The first aspect of this application provides a self-protection method for an industrial control computer, the self-protection method for the industrial control computer comprising:

[0006] When the industrial control computer is powered on, it acquires the reference voltage constant and, based on the preset sampling rules, collects the state sampling voltage related to the input voltage.

[0007] Based on the state sampling voltage and the reference voltage constant, the system operating state of the industrial control computer is determined;

[0008] Based on the system's operating state, a drive signal is generated. The drive signal includes at least a turn-off drive signal and a turn-on drive signal. The drive signal is used to drive the power switching element of the power path connected to the input voltage and the downstream load circuit to turn off or on.

[0009] By adopting the above technical solution, and by acquiring a reference voltage constant and collecting state sampling voltage, a stable and reliable reference benchmark and real-time input voltage data can be provided for subsequent system state judgment, thereby ensuring the accuracy and timeliness of the entire protection decision. By determining the system operating state based on the state sampling voltage and the reference voltage constant, it is possible to accurately identify whether the current input voltage is within the normal range or an abnormal fault range, thereby realizing intelligent perception of the power supply state. By generating drive signals based on the system operating state to drive power switching elements, the power supply path can be quickly and deterministically connected or disconnected, effectively protecting the downstream load circuit, and thus improving the industrial control computer's own protection capability against abnormal power supply voltage.

[0010] Optionally, the industrial control computer self-protection method further includes:

[0011] After the industrial computer is powered on, the input voltage is shunted and regulated by a parallel voltage regulator to obtain the reference voltage constant.

[0012] Based on the default state of the industrial control computer, the power path power switch element is set to the default off state.

[0013] By adopting the above technical solution, after the industrial control computer is powered on, the input voltage is shunted and regulated by a parallel voltage regulator to obtain a constant reference voltage. The excellent voltage regulation characteristics and low temperature drift coefficient of the parallel voltage regulator can be used to provide a high-precision judgment benchmark for the entire protection system, thereby greatly improving the accuracy and reliability of overvoltage and undervoltage protection thresholds. By setting the power path power switching components to the default off state according to the default state of the industrial control computer, it can be ensured that the power path is in a safe isolated state when the control logic is not yet stable in the early stage of system power-on, thereby effectively avoiding the impact and damage to the downstream precision circuits caused by the surge current or unstable voltage at the moment of power-on.

[0014] Optionally, the step of collecting state sampling voltages related to the input voltage based on preset sampling rules specifically includes:

[0015] Obtain the voltage divider type of the voltage divider network;

[0016] The sampling rules are generated based on the voltage divider type;

[0017] Based on the voltage divider type and the sampling rule, the input voltage is sampled to obtain the state sampling voltage, which includes at least a first state sampling voltage and a second state sampling voltage.

[0018] By adopting the above technical solution, and by obtaining the voltage division type of the voltage divider network and generating sampling rules, it is possible to configure sensing channels with specific voltage division ratios according to different protection targets, such as overvoltage protection or undervoltage protection, thereby making the sampling mechanism more targeted and accurate. By sampling the input voltage based on the voltage division type to obtain the first sampling voltage and the second state sampling voltage, it is possible to achieve parallel and multi-dimensional monitoring of the same input voltage, thereby providing a comprehensive data foundation for constructing a complete voltage safety working window.

[0019] Optionally, the step of determining the system operating state of the industrial control computer based on the state sampling voltage and the reference voltage constant specifically includes:

[0020] The first state sampling voltage and the second state sampling voltage in the state sampling voltage are compared with the reference voltage constant to obtain the comparison result;

[0021] Based on the comparison results, the system operating status of the industrial control computer is determined, and the system operating status includes at least normal operating status, overvoltage fault status, and undervoltage fault status.

[0022] By adopting the above technical solution, and by comparing the first sampling voltage and the second state sampling voltage with the reference voltage constant, the high-speed characteristics of the hardware comparator can be used to make real-time and parallel judgments on whether the input voltage exceeds the upper safety limit or falls below the lower safety limit, thereby realizing instantaneous detection of fault events. By determining the system operating state based on the comparison results, including at least normal, overvoltage fault, and undervoltage fault states, the health status of the power supply can be clearly classified and diagnosed, thus providing a clear decision basis for subsequent targeted protection measures.

[0023] Optionally, the step of determining the system operating state of the industrial control computer as the overvoltage fault state specifically includes:

[0024] The reference voltage constant is applied to the inverting input of the first voltage comparator, and the first state sampling voltage is applied to the non-inverting input of the first voltage comparator.

[0025] When the first state sampling voltage is greater than the reference voltage constant, the system operating state is determined to be the overvoltage fault state.

[0026] By adopting the above technical solution, a standard non-inverting comparator circuit structure can be constructed by applying a constant reference voltage to the inverting input of the first voltage comparator and applying the first state sampling voltage to the non-inverting input. This circuit is specifically designed to detect whether the voltage exceeds a certain threshold, making the overvoltage detection circuit implementation simple and efficient. By determining an overvoltage fault state when the first state sampling voltage is greater than the constant reference voltage, it can be ensured that once the input voltage exceeds the preset safety limit, the system can immediately trigger the overvoltage protection logic, thereby achieving rapid response and effective protection against high voltage surges.

[0027] Optionally, the step of determining the system operating state of the industrial control computer as the undervoltage fault state specifically includes:

[0028] The reference voltage constant is applied to the non-inverting input of the second voltage comparator, and the second state sampling voltage is applied to the inverting input of the second voltage comparator.

[0029] When the second state sampling voltage is less than the reference voltage constant, the system operating state is determined to be the undervoltage fault state.

[0030] By adopting the above technical solution, a standard inverting comparator circuit structure can be constructed by applying a constant reference voltage to the non-inverting input of the second voltage comparator and applying the second state sampling voltage to the inverting input. This circuit is specifically designed to detect whether the voltage is below a certain threshold, thus making the undervoltage detection circuit implementation simple and efficient. By determining the undervoltage fault state when the second state sampling voltage is less than the constant reference voltage, it can be ensured that once the input voltage drops below the preset safety lower limit, the system can immediately trigger the undervoltage protection logic, thereby effectively avoiding the risk of system crash or data loss caused by the industrial control computer operating abnormally under unstable low voltage.

[0031] Optionally, when the first state sampling voltage is less than the reference voltage constant and the second state sampling voltage is greater than the reference voltage constant, the system operating state is determined to be the normal operating state.

[0032] By adopting the above technical solution, the normal operating state is determined when the sampling voltage of the first state is less than the reference voltage constant and the sampling voltage of the second state is greater than the reference voltage constant. The safe operating range of the system can be defined by a strict double AND logic condition, thereby avoiding possible protection logic misjudgment or system oscillation when the voltage fluctuates near the critical point, and significantly enhancing the stability and reliability of the entire protection method.

[0033] The second aspect of this application provides an industrial control computer self-protection circuit, which is applied to the industrial control computer self-protection method of the first aspect. The industrial control computer self-protection circuit includes a parallel voltage regulator, a first voltage divider network, a second voltage divider network, a first voltage comparator, a second voltage comparator, a logic aggregation network, and a power path power switching element.

[0034] The input terminal of the parallel voltage regulator is connected to the input voltage of the industrial control computer. The reference voltage output terminal of the parallel voltage regulator is used to output the reference voltage constant. The reference voltage output terminal is connected to the inverting input terminal of the first voltage comparator and the non-inverting input terminal of the second voltage comparator, respectively.

[0035] The input terminal of the first voltage divider network is connected to the input voltage, and the output terminal of the first voltage divider network is connected to the non-inverting input terminal of the first voltage comparator.

[0036] The input terminal of the second voltage divider network is connected to the input voltage, and the output terminal of the second voltage divider network is connected to the inverting input terminal of the second voltage comparator.

[0037] The output terminals of the first voltage comparator and the second voltage comparator are both connected to the input terminal of the logic aggregation network;

[0038] The output terminal of the logic aggregation circuit is connected to the control terminal of the power path power switch element, which is connected in series between the input voltage and the back-end load circuit.

[0039] By adopting the above technical solution, and by using a circuit structure including parallel voltage regulators, voltage divider networks, voltage comparators, logic aggregation networks, and power switching elements, and specifying their specific connection relationships, a physical implementation scheme that completely integrates the aforementioned self-protection method into hardware can be provided. This leverages the advantages of pure hardware circuits to achieve low-cost, high-efficiency built-in voltage protection, avoiding dependence on expensive external equipment and enhancing the core competitiveness of industrial control computer products.

[0040] Optionally, the logic aggregation network includes a first MOS transistor and a second MOS transistor;

[0041] The output of the first voltage comparator is connected to the gate of the first MOS transistor;

[0042] The output of the second voltage comparator is connected to the gate of the second MOS transistor;

[0043] The drain of the first MOSFET is connected to the drain of the second MOSFET, and the connection node between the first MOSFET and the second MOSFET serves as the output terminal of the logic aggregation circuit. The sources of the first MOSFET and the second MOSFET are both grounded.

[0044] By adopting the above technical solution, the logic aggregation network includes a first MOSFET and a second MOSFET connected to their drains. The open-drain characteristics of the MOSFETs can be used to form a passive and efficient wire-AND logic gate, thereby aggregating the two independent fault signals of overvoltage and undervoltage with the fewest components. This simplifies circuit design, reduces costs and failure rates, and ensures that any fault can trigger the final protection action first.

[0045] Optionally, the power switching element in the power path is a P-channel MOSFET;

[0046] The source of the P-channel MOSFET is connected to the input voltage, and the drain of the P-channel MOSFET is connected to the back-end load circuit.

[0047] The source and gate of the P-channel MOS transistor are connected by a pull-up resistor.

[0048] By adopting the above technical solution, and using a P-channel MOSFET as the power switching element in the power path, a high-side switching driving method can be used, simplifying the design of the gate drive circuit and making the implementation of the entire execution module more convenient and economical. By connecting a pull-up resistor between the source and gate of the P-channel MOSFET, the MOSFET can be forcibly turned off when the system is powered on, thereby achieving a simple and reliable hardware-level power-on default safety protection, providing an extra layer of safety for the entire industrial control computer system.

[0049] In summary, this application includes at least one of the following beneficial technical effects:

[0050] 1. By acquiring a reference voltage constant and collecting status sampling voltage, a stable and reliable reference base and real-time input voltage data can be provided for subsequent system status judgment, thereby ensuring the accuracy and timeliness of the entire protection decision. By determining the system operating status based on the status sampling voltage and the reference voltage constant, it is possible to accurately identify whether the current input voltage is within the normal range or an abnormal fault range, thereby realizing intelligent perception of the power supply status. By generating drive signals based on the system operating status to drive power switching elements, it is possible to quickly and deterministically connect or disconnect the power supply path, effectively protecting the downstream load circuit, and thus improving the industrial control computer's own protection capability against abnormal power supply voltage.

[0051] 2. By adopting a circuit structure that includes parallel voltage regulators, voltage divider networks, voltage comparators, logic aggregation networks, and power switching elements, and specifying their particular connection relationships, a physical implementation scheme that completely integrates the aforementioned self-protection method into hardware can be provided. This leverages the advantages of pure hardware circuits to achieve low-cost, high-efficiency built-in voltage protection, avoiding dependence on expensive external equipment and enhancing the core competitiveness of industrial control computer products. Attached Figure Description

[0052] Figure 1 This is a flowchart illustrating the implementation of the self-protection method for industrial control computers in one embodiment of this application;

[0053] Figure 2 This is a partial circuit diagram of the self-protection circuit of the industrial control computer in one embodiment of this application. Detailed Implementation

[0054] The following embodiments will help those skilled in the art to further understand the function of this application, but do not limit this application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this application. These all fall within the protection scope of this application.

[0055] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0056] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0057] The present application will be further described in detail below with reference to the accompanying drawings.

[0058] In one embodiment, such as Figure 1 As shown, this application discloses a self-protection method for industrial control computers, which specifically includes the following steps:

[0059] S10: When the industrial control computer is powered on, it acquires the reference voltage constant and, based on the preset sampling rules, collects the state sampling voltage related to the input voltage.

[0060] Specifically, after the industrial control computer starts up and obtains the input voltage, a parallel voltage regulator can be used to shunt and regulate the input voltage, thereby obtaining a reference voltage constant (e.g., 2.5V) at its reference voltage output terminal, which is unaffected by fluctuations in the input voltage within a certain range and has high stability and low temperature drift characteristics. Simultaneously, the acquisition of the status sampling voltage is accomplished through two independent resistor divider networks, which continuously and asynchronously sample the input voltage, converting the analog input voltage signal into a proportionally scaled voltage signal that can be processed by the comparator in real time.

[0061] S20: Determine the system operating status of the industrial control computer based on the state sampling voltage and the reference voltage constant.

[0062] Specifically, by comparing the amplitude of the real-time changing state sampling voltage with a constant reference voltage, it can be determined whether the current input voltage is in a safe or dangerous range. For example, it can be set that when the sampling voltage is within a certain percentage range of the reference voltage, it is judged as a normal working state, and if it exceeds this range, it is judged as a fault state, thus providing decision input for whether to perform protection actions.

[0063] S30: Based on the system operating state, generate drive signals. The drive signals include at least a turn-off drive signal and a turn-on drive signal. The drive signals are used to drive the power switching elements of the power path connected to the input voltage and the downstream load circuit to turn off or on.

[0064] Specifically, once the preceding steps determine that the system's operating state is faulty, a clear level signal will be generated, such as a high level as a shutdown drive signal. This signal is applied to the control terminal of the power switch element in the power path, causing it to immediately shut down, thereby physically cutting off the connection between the input power supply and the downstream precision circuit, thus playing a protective role. Conversely, if the system is determined to be normal, another level signal will be generated, such as a low level as a conduction drive signal, keeping the power switch element in the power path on, so as to quickly cut off or connect the power supply path to the downstream load circuit.

[0065] In one embodiment, the industrial control computer self-protection method further includes:

[0066] S100: After the industrial control computer is powered on, the input voltage is shunted and regulated through a parallel voltage regulator to obtain a constant reference voltage.

[0067] Specifically, a parallel voltage regulator is used, and through its matching current-limiting resistor, a portion of the current can be separated from the fluctuating input voltage. Utilizing the characteristics of its internal bandgap reference source, an extremely stable 2.5V DC voltage is generated on its reference pin. This voltage has an extremely low temperature drift coefficient, ensuring a reliable judgment benchmark in various industrial environments.

[0068] S200: Based on the default state of the industrial control computer, the power path power switch element is set to the default off state.

[0069] Specifically, to ensure the absolute safety of the industrial control computer during startup and in the event of a fault in the protection circuit itself, the circuit design ensures that the power switching element is in a high-impedance off state when it does not receive a valid turn-on signal. For example, a P-channel MOSFET can be selected as the switching element, and a pull-up resistor can be connected between its gate and source. In this way, when the control signal is in a high-impedance state or uncertain, the gate level will be pulled up to be equal to the source level, thereby reliably turning it off. This effectively prevents current surges that may occur during power-on due to uncertain logic states, protecting the expensive load circuits at the back end.

[0070] In one embodiment, step S10, namely the step of acquiring state sampling voltages related to the input voltage based on preset sampling rules, specifically includes:

[0071] S11: Get the voltage divider type of the voltage divider network.

[0072] Specifically, the voltage divider type refers to the specific configuration of the hardware circuit used to achieve voltage sampling. In this embodiment, the type is determined to be a passive resistor voltage divider circuit composed of two or more physical resistors connected in series. This circuit structure is simple, reliable, and inexpensive. Moreover, its voltage division ratio is determined only by the resistance value of the resistors and is not affected by external factors such as temperature and frequency, which can ensure the stability and consistency of the sampling results.

[0073] S12: Generate sampling rules based on the voltage divider type.

[0074] Specifically, the sampling rule is a mathematical conversion relationship generated based on the known type of resistor divider network and its determined resistance parameters, such as the values ​​of R1 and R2. This rule clarifies the fixed proportional relationship between the input voltage and the sampling voltage, i.e., V_sample = V_in × (R2 / (R1+R2)). Through this rule, subsequent circuit design or software algorithms can accurately determine which specific level of the sampling voltage to correspond to for overvoltage or undervoltage protection points, such as 5.5V or 4.5V. Once the circuit is powered on, the two voltage divider networks act as two independent sensing channels, continuously converting the input voltage. This means that the system's response to voltage fluctuations is instantaneous, without any delay, ensuring real-time protection.

[0075] S13: Based on the voltage divider type and sampling rules, the input voltage is sampled to obtain the state sampling voltage, which includes at least the first state sampling voltage and the second state sampling voltage.

[0076] Specifically, two independent resistor divider networks are used to process the input voltage simultaneously. The first type is an overvoltage detection divider network, which is set up to monitor overvoltage, and its output is the first-state sampling voltage. The second type is an undervoltage detection divider network, which is set up to monitor undervoltage, and its output is the second-state sampling voltage. This dual-channel parallel sampling method allows overvoltage and undervoltage monitoring to be performed simultaneously without interference, improving the comprehensiveness of protection and response speed.

[0077] In one embodiment, step S20, namely the step of determining the system operating state of the industrial control computer based on the state sampling voltage and the reference voltage constant, specifically includes:

[0078] S21: Compare the first state sampling voltage and the second state sampling voltage in the state sampling voltage with the reference voltage constant to obtain the comparison result.

[0079] Specifically, the first state sampling voltage from the first voltage divider network is sent to the input of the first comparator, and the second state sampling voltage from the second voltage divider network is sent to the input of the second comparator. A reference voltage constant of 2.5V is simultaneously sent to the other input of the two comparators. The two comparators will perform differential amplification and judgment on the voltage level of their two inputs in parallel and continuously, thereby instantaneously outputting a logic level signal representing the comparison result.

[0080] S22: Based on the comparison results, determine the system operating status of the industrial control computer. The system operating status includes at least the normal operating status, the overvoltage fault status, and the undervoltage fault status.

[0081] Specifically, the current system operating state can be uniquely determined by combining the logic levels output by the two comparators. If both comparator outputs are low, the system is considered to be in normal operating condition. If the first comparator output is high, the system is considered to be in an overvoltage fault state. If the second comparator output is high, the system is considered to be in an undervoltage fault state. This explicit correspondence allows the system to unambiguously identify the specific state of the power supply.

[0082] In one embodiment, step S22, namely the step of determining that the industrial control computer's system operating state is an overvoltage fault state, specifically includes:

[0083] S220: Apply a reference voltage constant to the inverting input of the first voltage comparator and apply the first state sampling voltage to the non-inverting input of the first voltage comparator.

[0084] Specifically, this particular connection method is key to achieving overvoltage detection. Connecting a stable 2.5V reference voltage constant to the inverting input of the first voltage comparator is equivalent to setting a fixed judgment threshold. Connecting the first state sampling voltage, which changes positively with the input voltage, to the non-inverting input ensures that the voltage at the non-inverting input increases as the input voltage increases.

[0085] S2201: When the first state sampling voltage is greater than the reference voltage constant, the system operating state is determined to be an overvoltage fault state.

[0086] Specifically, when the input voltage of the industrial control computer exceeds the preset safety limit of 5.5V, the first state sampling voltage obtained through the design of the first voltage divider network will exceed 2.5V. At this time, the voltage at the non-inverting input terminal of the first voltage comparator is higher than the voltage at the inverting input terminal. According to the working principle of the comparator, the level at its output terminal will immediately flip from low level to high level. This high-level signal is a clear indication that the system has entered an overvoltage fault state.

[0087] In one embodiment, step S22, namely the step of determining that the industrial control computer's system operating state is an undervoltage fault state, specifically includes:

[0088] S221: Apply a constant reference voltage to the non-inverting input of the second voltage comparator and apply the second state sampling voltage to the inverting input of the second voltage comparator.

[0089] Specifically, to achieve undervoltage detection, the second voltage comparator is connected in the opposite configuration to the first. A stable 2.5V reference voltage is connected to its non-inverting input, while a second-state sampling voltage that changes in the positive direction with the input voltage is connected to its inverting input. This configuration reverses the comparison logic, specifically for detecting whether the voltage is below a certain threshold.

[0090] S2211: When the second state sampling voltage is less than the reference voltage constant, the system operating state is determined to be an undervoltage fault state.

[0091] Specifically, when the input voltage of the industrial control computer drops below the preset safety lower limit of 4.6V, the second state sampling voltage obtained by voltage division through the second voltage divider network will be lower than 2.5V. At this time, the voltage at the inverting input terminal of the second voltage comparator is lower than the voltage at the non-inverting input terminal, and its output level will also flip from low to high. This high-level signal is a clear indication that the system has entered an undervoltage fault state.

[0092] In one embodiment, in step S22, when the first state sampling voltage is less than the reference voltage constant and the second state sampling voltage is greater than the reference voltage constant, the system operating state is determined to be a normal operating state.

[0093] Specifically, this dual condition defines the safe operating window of the power supply voltage. In the first state, a sampled voltage less than the reference voltage constant means the input voltage is below the overvoltage threshold, while in the second state, a sampled voltage greater than the reference voltage constant means the input voltage is above the undervoltage threshold. Only when both conditions are met simultaneously will the outputs of both comparators remain low. This double-negation logic state is uniquely interpreted by the system as the normal operating state, at which point the protection circuit will not trigger any action, allowing the power switching elements in the power path to remain on, providing a continuous and stable power supply to the downstream load.

[0094] Reference Figure 2 , Figure 2This application provides a circuit diagram of an industrial control computer (ICC) self-protection circuit applied to the aforementioned ICC self-protection method. The ICC self-protection circuit includes a parallel voltage regulator, a first voltage divider network, a second voltage divider network, a first voltage comparator, a second voltage comparator, a logic aggregation network, and a power path power switch element. The input terminal of the parallel voltage regulator is connected to the input voltage of the ICC. The reference voltage output terminal of the parallel voltage regulator is used to output a constant reference voltage, and the reference voltage output terminal is connected to the inverting input terminal of the first voltage comparator and the non-inverting input terminal of the second voltage comparator, respectively. The input terminal of the first voltage divider network is connected to the input voltage, and the output terminal of the first voltage divider network is connected to the non-inverting input terminal of the first voltage comparator. The input terminal of the second voltage divider network is connected to the input voltage, and the output terminal of the second voltage divider network is connected to the inverting input terminal of the second voltage comparator. The output terminals of both the first and second voltage comparators are connected to the input terminal of the logic aggregation network. The output terminal of the logic aggregation network is connected to the control terminal of the power path power switch element, which is connected in series between the input voltage and the downstream load circuit.

[0095] Specifically, this circuit implements a fully hardware-based self-protection logic through precise component interconnection. Its electrical connections are as follows: the positive terminal of the industrial control computer's input voltage serves as the circuit's common power supply node AD+, and the common ground terminal is GND. To generate an absolutely stable judgment benchmark, a parallel voltage regulator U1 is connected to the circuit. Its cathode pin is connected to AD+ through a current-limiting resistor to ensure its operating current remains within a safe range, while its anode pin is directly connected to GND. Its reference pin forms an extremely stable 2.5V reference voltage constant Vref25. To obtain the current changing in the same direction as AD+... For overvoltage monitoring signals, a first voltage divider network consisting of two physical resistors, R2 and R4, is introduced. The upper end of R2 is connected to VIN, and its lower end is connected to the upper end of R4 at a common node, which is the overvoltage sampling voltage output terminal V_S1. The lower end of R4 is connected to GND, thus generating a voltage at node V_S1 that is reduced from VIN according to the resistance ratio of R2 and R4. Similarly, to obtain the undervoltage monitoring signal, a second voltage divider network consisting of R87 and R88 is connected in series between AD+ and GND in the same manner, and its common node serves as the undervoltage sampling voltage output terminal V_S2. For bidirectional threshold judgment, an LM358 chip integrating two independent comparator units is used. The inverting input (V-) of the first comparator unit U11 is directly connected to the reference voltage pin VREF of the parallel regulator U1 to set the upper limit of the overvoltage alarm. Its non-inverting input (V+) is connected to the overvoltage sampling node V_S1 of the first voltage divider network to receive real-time monitoring values. The connection of the second comparator unit U22 is cleverly reversed: its non-inverting input (V+) is connected to the reference voltage pin VREF of the parallel regulator U1 to set the lower limit of the undervoltage alarm, and its inverting input (V-) is connected to the reference voltage pin VREF of the parallel regulator U1 to set the lower limit of the undervoltage alarm. The undervoltage sampling node V_S2 of the second voltage divider network is connected; the outputs Vout1 and Vout2 of the two comparators are connected to the input of the logic aggregation network, and the output COMP_OV of the logic aggregation network is sent out; finally, in order to perform power cut-off, the COMP_OV signal is applied to the control pin, i.e., the gate, of a power switching element in a power path, such as a P-channel MOSFET Q1. The source of this MOSFET Q1 is directly connected to VIN, and its drain is connected to the power input of the back-end load circuit of the industrial control computer. In this way, the power supply to the back-end load circuit is turned on or isolated for protection.

[0096] Based on the above embodiments, as an optional embodiment, the logic aggregation network includes a first MOS transistor and a second MOS transistor; the output terminal of the first voltage comparator is connected to the gate of the first MOS transistor; the output terminal of the second voltage comparator is connected to the gate of the second MOS transistor; the drain of the first MOS transistor is connected to the drain of the second MOS transistor; the connection node of the first MOS transistor and the second MOS transistor serves as the output terminal of the logic aggregation circuit; and the source of the first MOS transistor and the source of the second MOS transistor are both grounded.

[0097] Specifically, two identical low-power N-channel enhancement-type MOSFETs, such as 2N7002, are selected as the first MOSFET Q2 and the second MOSFET Q3, respectively. The output of the first voltage comparator U11 is directly connected to the gate of the first MOSFET Q2, and the output of the second voltage comparator U22 is directly connected to the gate of the second MOSFET Q3. This means that the output levels of the two comparators will independently control the on and off states of the corresponding MOSFETs. To achieve signal merging, the drains of the first MOSFET Q2 and the second MOSFET Q3 are physically connected to the same circuit node. To provide a common reference ground, the sources of both MOSFETs Q2 and Q3 are directly connected to the common ground GND of the circuit. This common-drain, common-source parallel connection method cleverly utilizes the switching characteristics of the MOSFETs to implement the OR logic function. Specifically, the signal output from the first voltage comparator U11 directly controls the first MOSFET Q3. The switching on and off of S-channel MOSFET Q2 is controlled by the signal output from the second voltage comparator U22, which in turn controls the switching on and off of the second MOSFET Q3. Since the drains of the two MOSFETs are physically connected to the same node, if either comparator detects a fault and outputs a high-level signal, its corresponding MOSFET will turn on, thus forcibly pulling the potential of the common node to ground. That is, when the first voltage comparator outputs a high level (e.g., 5V) due to overvoltage, this voltage is applied to the gate of the first MOSFET Q2, causing it to turn on and pulling the voltage of the common drain node to a low level close to ground. Similarly, when the second voltage comparator U22 outputs a high level due to undervoltage, it will also pull the node to a low level through the second MOSFET Q3. Conversely, only when neither comparator detects a fault and both output a low level simultaneously will both MOSFETs remain off, allowing the common node to present a high-level state. This structure ensures that any single fault can preferentially obtain control over the final drive signal.

[0098] Based on the above embodiments, as an optional embodiment, the power switching element in the power path is a P-channel MOSFET; the source of the P-channel MOSFET is connected to the input voltage, and the drain of the P-channel MOSFET is connected to the downstream load circuit; the source and gate of the P-channel MOSFET are connected through a pull-up resistor.

[0099] Specifically, the P-channel MOSFET, as the power switching element that performs the final protection action, is connected in series with the positive path of the main power supply as a high-side switch due to the connection between its source and drain. Its control terminal, i.e. the gate, receives the drive signal from the output terminal of the preceding logic aggregation network. When the signal is low, the P-channel MOSFET is turned on, and the power supply path is connected. When the signal is high, the P-channel MOSFET is turned off, and the power supply path is isolated.

[0100] In particular, connecting the source and gate of the P-channel MOSFET with a pull-up resistor is a key design feature to achieve the default safe state when the system is powered on. This pull-up resistor ensures that in the initial stage before the control logic is stably established, the gate potential of the P-channel MOSFET is forced to be pulled up to match the source potential, thereby reliably keeping it in the default off state and preventing the impact on the back-end load circuit at the moment of power-on.

[0101] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0102] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A self-protection method for industrial control computers, characterized in that, The industrial control computer self-protection method includes: When the industrial control computer is powered on, it acquires the reference voltage constant and, based on the preset sampling rules, collects the state sampling voltage related to the input voltage. Based on the state sampling voltage and the reference voltage constant, the system operating state of the industrial control computer is determined; Based on the system's operating state, a drive signal is generated. The drive signal includes at least a turn-off drive signal and a turn-on drive signal. The drive signal is used to drive the power switching element of the power path connected to the input voltage and the downstream load circuit to turn off or on.

2. The industrial control computer self-protection method according to claim 1, characterized in that, The industrial control computer self-protection method also includes: After the industrial computer is powered on, the input voltage is shunted and regulated by a parallel voltage regulator to obtain the reference voltage constant. Based on the default state of the industrial control computer, the power path power switch element is set to the default off state.

3. The industrial control computer self-protection method according to claim 1, characterized in that, The step of collecting state sampling voltages related to the input voltage based on preset sampling rules specifically includes: Obtain the voltage divider type of the voltage divider network; The sampling rules are generated based on the voltage divider type; Based on the voltage divider type and the sampling rule, the input voltage is sampled to obtain the state sampling voltage, which includes at least a first state sampling voltage and a second state sampling voltage.

4. The industrial control computer self-protection method according to claim 2, characterized in that, The step of determining the system operating state of the industrial control computer based on the state sampling voltage and the reference voltage constant specifically includes: The first state sampling voltage and the second state sampling voltage in the state sampling voltage are compared with the reference voltage constant to obtain the comparison result; Based on the comparison results, the system operating status of the industrial control computer is determined, and the system operating status includes at least normal operating status, overvoltage fault status, and undervoltage fault status.

5. The industrial control computer self-protection method according to claim 3, characterized in that, The step of determining that the system operating state of the industrial control computer is the overvoltage fault state specifically includes: The reference voltage constant is applied to the inverting input of the first voltage comparator, and the first state sampling voltage is applied to the non-inverting input of the first voltage comparator. When the first state sampling voltage is greater than the reference voltage constant, the system operating state is determined to be the overvoltage fault state.

6. The industrial control computer self-protection method according to claim 3, characterized in that, The step of determining the system operating state of the industrial control computer as the undervoltage fault state specifically includes: The reference voltage constant is applied to the non-inverting input of the second voltage comparator, and the second state sampling voltage is applied to the inverting input of the second voltage comparator. When the second state sampling voltage is less than the reference voltage constant, the system operating state is determined to be the undervoltage fault state.

7. The industrial control computer self-protection method according to claim 4 or 5, characterized in that, When the first state sampling voltage is less than the reference voltage constant and the second state sampling voltage is greater than the reference voltage constant, the system operating state is determined to be the normal operating state.

8. A self-protection circuit for an industrial control computer, characterized in that, The self-protection method for an industrial control computer as described in any one of claims 1-7 is provided, wherein the self-protection circuit for the industrial control computer includes a parallel voltage regulator, a first voltage divider network, a second voltage divider network, a first voltage comparator, a second voltage comparator, a logic aggregation network, and a power path switching element. The input terminal of the parallel voltage regulator is connected to the input voltage of the industrial control computer. The reference voltage output terminal of the parallel voltage regulator is used to output the reference voltage constant. The reference voltage output terminal is connected to the inverting input terminal of the first voltage comparator and the non-inverting input terminal of the second voltage comparator, respectively. The input terminal of the first voltage divider network is connected to the input voltage, and the output terminal of the first voltage divider network is connected to the non-inverting input terminal of the first voltage comparator. The input terminal of the second voltage divider network is connected to the input voltage, and the output terminal of the second voltage divider network is connected to the inverting input terminal of the second voltage comparator. The output terminals of the first voltage comparator and the second voltage comparator are both connected to the input terminal of the logic aggregation network; The output terminal of the logic aggregation circuit is connected to the control terminal of the power path power switch element, which is connected in series between the input voltage and the back-end load circuit.

9. The industrial control computer self-protection circuit according to claim 8, characterized in that, The logic aggregation network includes a first MOS transistor and a second MOS transistor; The output of the first voltage comparator is connected to the gate of the first MOS transistor; The output of the second voltage comparator is connected to the gate of the second MOS transistor; The drain of the first MOSFET is connected to the drain of the second MOSFET, and the connection node between the first MOSFET and the second MOSFET serves as the output terminal of the logic aggregation circuit. The sources of the first MOSFET and the second MOSFET are both grounded.

10. The industrial control computer self-protection circuit according to claim 9, characterized in that, The power switching element in the power path is a P-channel MOSFET. The source of the P-channel MOSFET is connected to the input voltage, and the drain of the P-channel MOSFET is connected to the back-end load circuit. The source and gate of the P-channel MOS transistor are connected by a pull-up resistor.

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