A protection threshold correction method, system, device and medium

Abstract

This invention discloses a protection threshold correction method, system, device, and medium, belonging to the field of power systems. The method comprises: a control measurement circuit measuring a first reference physical quantity in a power circuit to obtain multiple first sampling signals; processing each first sampling signal using initial parameters of a DSP controller to obtain each first digital signal; fitting each first digital signal and each first reference physical quantity to obtain DSP target parameters; a control signal generator outputting multiple analog signals to the sampling circuit; a comparator circuit triggering a protection action when the current sampling signal is greater than a trigger threshold; the DSP determining the actual protection threshold corresponding to the current digital signal based on the target parameters and the current sampling signal; and finally obtaining a preset protection threshold and correcting the actual protection threshold using the target parameters. Therefore, by implementing this invention, protection thresholds can be accurately calibrated without power instruments, reducing errors and improving the reliability of hardware protection in power electronic devices.

Description

Technical Field

[0001] This invention relates to the field of power systems, and more particularly to a protection threshold correction method, system, device, and medium. Background Technology

[0002] In high-power power electronic devices (such as power conversion modules, energy storage converters, and photovoltaic inverters), hardware protection circuits are the core modules ensuring the safety of critical components. The core of these hardware protection circuits is the "protection threshold." The protection threshold is generally obtained by directly setting a trigger threshold voltage and then calculating the relationship between the trigger threshold voltage and the actual protection threshold, or by directly measuring the power circuit using a power measuring instrument. In other words, to obtain an accurate actual protection threshold, a precise trigger threshold voltage must be set.

[0003] Currently, without using power measuring instruments, the actual protection threshold is corrected by improving the accuracy of the comparator's trigger threshold voltage to reduce the error between the actual protection threshold and the preset protection threshold. For example, the trigger threshold voltage of the comparator is generated by voltage division of a reference voltage source (such as fixed resistor voltage division or adjustable resistor voltage division), and the threshold voltage is modified by adjusting the resistance value of the resistor online to correct the actual protection threshold.

[0004] However, existing technologies do not take into account the errors in the actual protection threshold caused by inherent circuit errors, resulting in low accuracy of the actual protection threshold. Summary of the Invention

[0005] This invention provides a protection threshold correction method, system, device, and medium that can solve the problems of large errors and low accuracy between existing actual protection thresholds and preset protection thresholds.

[0006] This invention provides a protection threshold correction method applied to a power electronic device; the power electronic device includes: a power circuit, a measurement circuit, a comparator circuit, a DSP controller, and a signal generator; wherein the power circuit, the measurement circuit, and the comparator circuit are connected sequentially, and the sampling circuit in the measurement circuit is connected to the DSP controller and the signal generator respectively; the protection threshold correction method includes: The measurement circuit is controlled to measure the first reference physical quantity in the power circuit to obtain multiple first sampling signals output by the measurement circuit. The initial parameters of the DSP controller are then used to process each first sampling signal to obtain multiple first digital signals. The first reference physical quantity and the corresponding first digital signal are fitted and calculated to obtain the target parameters of the DSP controller. The signal generator is controlled to input multiple analog signals to the sampling circuit for sampling. When the comparator circuit determines that the current sampled signal is greater than the trigger threshold of the comparator circuit, a protection action is triggered. Based on the target parameter and the current sampled signal, the DSP controller determines the current digital signal and uses the physical quantity corresponding to the current digital signal as the actual protection threshold. Obtain a preset protection threshold, and correct the actual protection threshold based on the preset protection threshold and the target parameter.

[0007] This invention eliminates errors in the measurement circuit (sensor, sampling circuit) by fitting and calculating calibrating the DSP controller parameters. Then, based on the calibrated DSP controller, the actual protection threshold is determined and calibrated, effectively reducing the error between the actual protection threshold and the preset protection threshold, and improving the accuracy and reliability of the hardware protection of power electronic devices. Furthermore, by obtaining the target parameters through fitting and calculating the measurement circuit and the DSP controller, and then combining the signal generator to simulate the signal to trigger the protection action to determine the actual protection threshold, there is no need to rely on power measurement instruments, avoiding the safety risks of high voltage and high current, and reducing the cost of relying on expensive power instruments during the research and development stage.

[0008] Furthermore, the comparator circuit also includes a reference voltage source and a voltage divider module. The voltage divider module includes an adjustable resistor and a fixed resistor. The trigger threshold is obtained by dividing the reference voltage output from the reference voltage source using the adjustable resistor. The correction of the actual protection threshold based on the preset protection threshold and the target parameter specifically involves: The intensity change state of the second analog signal is determined based on the actual protection threshold and the preset protection threshold; Based on the intensity change state, the signal generator is controlled to input multiple second analog signals to the sampling circuit for sampling; The current second digital signal is determined based on the target parameters and the current second sampling signal. When the physical quantity corresponding to the current second digital signal is equal to the preset protection threshold, the trigger threshold is updated by adjusting the adjustable resistor until the trigger state of the comparator circuit changes, at which point the actual protection threshold is corrected to the preset protection threshold.

[0009] This explicit method of generating the trigger threshold (adjustable resistor voltage divider) allows for flexible updates of the trigger threshold by adjusting the adjustable resistor, without requiring modifications to the overall hardware circuit structure. This solves the problem of inaccurate threshold adjustment and the need for hardware modifications in traditional resistor voltage divider schemes, significantly improving the convenience of threshold adjustment. By controlling the analog signal strength and adjusting the adjustable resistor based on the difference between the actual and preset thresholds, the final actual protection threshold is ensured to match the preset protection threshold, reducing the error from over 5% in existing technologies to approximately 1%. This significantly improves the calibration accuracy of the hardware protection threshold and meets the reliability requirements of power electronic devices.

[0010] Furthermore, determining the intensity change state of the second analog signal based on the actual protection threshold and the preset protection threshold specifically involves: If the actual protection threshold is greater than the preset protection threshold, then the intensity of the analog signal corresponding to the current sampled signal is used as the initial signal intensity, and the initial signal intensity is decreased sequentially based on a preset step value to obtain each second analog signal; If the actual protection threshold is less than or equal to the preset protection threshold, then the intensity of the analog signal corresponding to the current sampled signal is used as the initial signal intensity, and the initial signal intensity is increased sequentially based on the preset step value to obtain each second analog signal.

[0011] This provides clear and quantifiable rules for adjusting the analog signal strength, avoiding blind adjustments, shortening analog signal debugging time, and improving the efficiency of protection threshold calibration. By adjusting the analog signal strength based on the difference between the actual value and the preset threshold, it ensures that the analog signal accurately approximates the signal strength corresponding to the preset protection threshold. This provides a precise signal basis for subsequent adjustable resistor adjustments and threshold updates, further guaranteeing the final calibration accuracy.

[0012] Furthermore, the step of updating the trigger threshold by adjusting the resistance value of the adjustable resistor until the trigger state of the comparator circuit changes specifically involves: If the actual protection threshold is greater than the preset protection threshold, when the physical quantity corresponding to the current digital signal determined according to the target parameter is equal to the preset protection threshold, and the protection action of the comparator circuit is released, the resistance value of the adjustable resistor is controlled to decrease until the protection action of the comparator circuit is triggered. If the actual protection threshold is less than or equal to the preset protection threshold, when the physical quantity corresponding to the current digital signal determined according to the target parameter is equal to the preset protection threshold, and the protection action of the comparator circuit is triggered, the resistance value of the adjustable resistor is increased until the protection action of the comparator circuit is released.

[0013] This clearly defines the "preconditions" (the physical quantity of the digital signal equals the preset value + the specific operating state of the comparator) and the "adjustment direction" (the resistance decreases when the actual value is large, and increases when the actual value is small), avoiding the problems of "repeated trial and error and inability to locate the critical value" in traditional adjustable resistor adjustments. There is no need to measure intermediate parameters (such as the trigger threshold voltage) multiple times. Adjustment can be directionally performed based solely on two intuitive states: "whether the digital signal meets the standard" and "whether the protection action meets expectations," which greatly shortens the calibration time. During the adjustment process, the resistance adjustment direction will not be incorrect due to "the digital signal not matching the preset value," reducing the risk of calibration failure. This is especially suitable for the demand for efficient and reliable calibration in the mass production stage.

[0014] Furthermore, the measurement circuit in the power electronic device also includes a sensor, and the control of the signal generator to input multiple analog signals to the sampling circuit for sampling is specifically as follows: Determine the measurement range of the power circuit; The sensitivity parameters of the sensor are obtained, and the intensity range of each analog signal is calculated based on the sensitivity parameters and the measurement range. A second step value is obtained, and the intensity range is linearly increased based on the second step value to obtain a plurality of analog sequence signals that increase sequentially. Each of the analog sequence signals is then input into the sampling circuit sequentially.

[0015] This method calculates the analog signal strength range based on the actual measurement range of the power circuit and sensor parameters, ensuring that the analog signal covers the measured range in the real working scenario of the power circuit. This avoids the analog signal exceeding actual needs or failing to cover critical intervals, thus improving the effectiveness and specificity of the analog signal. The analog sequence signal is generated by linearly increasing the second step value, making the signal strength change smooth and controllable. This facilitates accurate capture of the critical signal (i.e., the signal corresponding to the actual protection threshold) that triggers the comparator circuit's protection action, avoiding the problem of missing critical values ​​and affecting calibration accuracy due to excessive signal jumps.

[0016] Furthermore, the power electronic device also includes an indicator module and a programmable logic device. The indicator module includes a first LED and a second LED. The programmable logic device is connected to the comparator circuit and the DSP controller, respectively, for latching the trigger state of the protection action. The first LED is connected to the comparator circuit, and the second LED is connected to the programmable logic device. The protection threshold correction method further includes: When the comparator circuit triggers a protection action, it controls the first LED to turn on, latches the trigger state through the programmable logic device, and controls the second LED to turn on. The programmable logic device generates a fault signal and sends it to the DSP controller, which then controls the power circuit to stop outputting power. When the comparator circuit deactivates its protection mechanism, the first LED is turned off, while the second LED remains on until a fault reset command is received, at which point the second LED is turned off.

[0017] This dual-LED indicator design addresses the issue of rapid hardware protection action (µs-level response) being difficult for the human eye to detect, allowing for intuitive observation of protection activation during calibration. The second LED, latched by a programmable logic device (PLD), solves the problem of slow hardware protection action response (µs-level) being difficult to detect by the human eye, facilitating fault location and troubleshooting and improving debugging convenience. The PLD latches the trigger state and generates a fault signal, ensuring the DSP controller can promptly receive fault information and cut off power circuit output. This prevents the controller from misjudging fault clearance and continuing output due to the instantaneous termination of protection action, potentially leading to more serious accidents. Furthermore, the PLD's µs-level response speed does not compromise the speed of hardware protection, balancing protection reliability and anti-interference capabilities.

[0018] Furthermore, the sampling circuit in the power electronic device includes an operational amplifier and a bias voltage source. The first sampling signal is determined based on the bias voltage output by the bias voltage source and the scaling factor of the operational amplifier, specifically: Acquire the sensor signal output by the sensor; scale the sensor signal according to the scaling factor, and superimpose the bias voltage to obtain the sampled signal.

[0019] This method adjusts the sensor signal amplitude by adjusting the scaling factor of the operational amplifier, ensuring the sampled signal matches the reference voltage range of the DSP controller's ADC (e.g., 0~3V). This avoids distortion or measurement errors caused by the signal exceeding the ADC's measurement range. Adding a bias voltage (e.g., 1.5V) addresses the potential negative voltage issue in the sensor signal, ensuring the sampled signal is always positive, meeting the ADC's positive voltage measurement requirements, and improving the effectiveness and accuracy of the sampled signal. By clearly defining the generation process of the sampled signal and through the synergistic effect of the scaling factor and bias voltage, a precise conversion from the sensor signal to the sampled signal is achieved. This provides a high-quality sampled data foundation for the subsequent DSP controller to fit and calculate target parameters and determine the digital signal, indirectly improving the overall accuracy of the protection threshold calibration.

[0020] Another embodiment of the present invention provides a protection threshold correction system applied to a power electronic device; the power electronic device includes: a power circuit, a measurement circuit, a comparator circuit, a DSP controller, and a signal generator; wherein the power circuit, the measurement circuit, and the comparator circuit are connected in sequence, and the sampling circuit in the measurement circuit is connected to the DSP controller and the signal generator respectively; the protection threshold correction system includes: a measurement correction module, an actual threshold module, and a threshold correction module; The measurement correction module is used to control the measurement circuit to measure the first reference physical quantity in the power circuit, obtain multiple first sampling signals output by the measurement circuit, process each first sampling signal through the initial parameters of the DSP controller to obtain multiple first digital signals, and perform fitting calculation on each first reference physical quantity and the corresponding first digital signal to obtain the target parameters of the DSP controller. The actual threshold module is used to control the signal generator to input multiple analog signals to the sampling circuit for sampling. When the comparator circuit determines that the current sampled signal is greater than the trigger threshold of the comparator circuit, it triggers a protection action. Based on the target parameter and the current sampled signal, the DSP controller determines the current digital signal and uses the physical quantity corresponding to the current digital signal as the actual protection threshold. The threshold correction module is used to obtain a preset protection threshold and correct the actual protection threshold according to the preset protection threshold and the target parameter.

[0021] The embodiments of the present invention have been successfully implemented.

[0022] Another embodiment of the present invention provides a terminal device, including: a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, it implements the steps of the protection threshold correction method of the present invention.

[0023] Another embodiment of the present invention provides a computer-readable storage medium item, including: a stored computer program, which, when the computer program is running, controls the device where the computer-readable storage medium is located to perform steps as described in the protection threshold correction method of the present invention. Attached Figure Description

[0024] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1This is a schematic flowchart of a protection threshold correction method provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the calibration process of a measurement circuit provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of an actual protection threshold determination process provided by an embodiment of the present invention; Figure 4 This is a schematic flowchart of another protection threshold correction method provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of a protection threshold correction system provided in an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0028] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0029] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0030] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0031] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0032] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0033] See Figure 1 To address the problem of large errors and low accuracy between the actual protection threshold and the preset protection threshold in existing technologies, an embodiment of the present invention provides a protection threshold correction method, applicable to, for example... Figure 2 The power electronic device shown includes: a power circuit, a measurement circuit, a comparator circuit, a DSP controller, and a signal generator; wherein the power circuit, the measurement circuit, and the comparator circuit are connected in sequence, and the sampling circuit in the measurement circuit is connected to the DSP controller and the signal generator respectively; the protection threshold correction method includes steps S101-S103, specifically including: Step S101: Control the measurement circuit to measure the first reference physical quantity in the power circuit, obtain multiple first sampling signals output by the measurement circuit, process each first sampling signal through the initial parameters of the DSP controller to obtain multiple first digital signals, and perform fitting calculation on each first reference physical quantity and the corresponding first digital signal to obtain the target parameters of the DSP controller.

[0034] As an example of an embodiment of the present invention, the sampling circuit in the power electronic device includes an operational amplifier and a bias voltage source. The first sampling signal is determined based on the bias voltage output by the bias voltage source and the scaling factor of the operational amplifier, specifically: Acquire the sensor signal output by the sensor; scale the sensor signal according to the scaling factor, and superimpose the bias voltage to obtain the sampled signal.

[0035] It should be noted that the scaling factor K p It is a key parameter of the operational amplifier circuit, and the sampled signal V output by the sampling circuit is... sam The voltage range depends on the reference voltage of the ADC in the DSP controller. The reference voltage of the ADC is typically 0~3.3V or 0~3V, and the bias voltage V... p Then it is the sampled signal V sam Half of the range, that is, 1.65V or 1.5V.

[0036] In this embodiment, as Figure 2 As shown, the measurement circuit includes a sensor adapted to the first reference physical quantity (voltage / current of the power circuit) and a sampling circuit with an operational amplifier and a bias voltage source, and all components are connected normally. Three or more sets of the first reference physical quantities (e.g., 80%, 100%, and 120% of the rated voltage) are selected within the normal operating range of the power circuit, and the measurement circuit is controlled to measure them: the sensor acquires the physical quantity and converts it into a -5V to +5V sensor signal (V...). Sen =Physical quantity V A × Sensor sensitivity S N The sampling circuit passes through an operational amplifier (according to the scaling factor K). p Adjust the signal amplitude and add a bias voltage V. p (e.g., 1.5V), generate the first sampling signal (V) sam =V Sen ×K p +V p Multiple sets of first sampling signals are obtained. The first sampling signals are transmitted to the DSP controller. The DSP uses the factory default initial parameters (including ADC reference voltage, sampling accuracy, etc.) to convert the analog signal into the ADC raw reading through the ADC module. Then, according to the initial parameters of the ADC module, the ADC raw reading is converted into multiple sets of first digital signals. With the first reference physical quantity as the dependent variable and the first digital signal as the independent variable, linear least squares fitting is used to establish y=ax+b (a is the slope and b is the intercept), that is, the first reference physical quantity = a× the initial digital quantity + b (a is the slope and b is the intercept) to minimize the sum of squared deviations. The solved a and b are the target parameters of the DSP controller, eliminating the error between the measurement circuit and the DSP initial parameters.

[0037] This embodiment completes sensor calibration according to the measurement path of "Measured Item → Sensor → Sampling Circuit → DSP Controller Measurement Reading," eliminating errors in the sensor and sampling circuit along the path, so that the DSP controller's measurement reading directly reflects the actual measured value. This path is a linear measurement system. It only requires the use of a measuring instrument or a DSP simulator to read multiple sets of measured and ADC measurement readings, and then employs a linear least squares fitting method to complete sensor calibration. At this point, the DSP controller's ADC measurement reading Num should correspond to the measured voltage or current reading (V). A Or I A The values ​​are equal, and the error can be accurate to one decimal place.

[0038] Step S102: Control the signal generator to input multiple analog signals to the sampling circuit for sampling. When the comparator circuit determines that the current sampled signal is greater than the trigger threshold of the comparator circuit, it triggers a protection action. Based on the target parameter and the current sampled signal, the DSP controller determines the current digital signal and uses the physical quantity corresponding to the current digital signal as the actual protection threshold.

[0039] It should be noted that the trigger threshold voltage V th A reference voltage source V is typically used. ref =3V is obtained through resistor voltage division or other methods, i.e., V th =V ref x R1 / (R1+R2), the trigger signal V output by the comparator in the protection circuit. o Satisfying the equality relationship V o =α(V sam -V th ), where α is infinity, and in fact V o It is a digital signal representing high and low voltage levels. Its upper and lower limits depend on the voltage range of the control unit. Generally, the high level is 3.3V and the low level is 0V. The trigger signal V o A high level indicates an overvoltage or overcurrent fault, while a low level indicates no fault.

[0040] In this embodiment, as Figure 3 As shown, referring to the sensor input-output relationship, the control signal generator outputs multiple incremental analog signals to the sampling circuit with preset step values. The sampling circuit generates the current sampling signal according to the S101 logic (operational amplifier scaling + bias voltage superposition) and synchronously transmits it to the comparator circuit and DSP. The comparator compares the current sampling signal with the trigger threshold; if the former is larger, it triggers a protection action (outputs a high level). At this time, the DSP, based on the target parameters, converts the current sampling signal through an ADC and substitutes it into the correction formula to obtain the current digital signal Num. The physical quantity corresponding to this digital signal represents the actual protection threshold V. TH .

[0041] As an example of an embodiment of the present invention, the measurement circuit in the power electronic device further includes a sensor, and the control of the signal generator to input multiple analog signals to the sampling circuit for sampling is specifically as follows: The measurement range of the power circuit is determined; the sensitivity parameters of the sensor are obtained, and the intensity range of each analog signal is calculated based on the sensitivity parameters and the measurement range; a second step value is obtained, and the intensity range is linearly increased based on the second step value to obtain a plurality of analog sequence signals that increase sequentially, and each analog sequence signal is sequentially input into the sampling circuit.

[0042] In this embodiment, when performing the operation of "controlling the signal generator to input multiple analog signals to the sampling circuit for sampling", the measurement range of the power circuit of the power electronic device is first defined. This range needs to cover the fluctuation range of the measured (such as voltage and current) when the power circuit is working normally and the critical range that may trigger the protection action. For example, if the power circuit is an AC-DC power converter, and its rated output voltage is 600V, and the protection threshold is designed to be 1.4 times the rated value (i.e., 840V), then the measurement range of the power circuit is set to 0V-900V to ensure that it includes the normal operating voltage and the critical voltage of the protection action.

[0043] Next, obtain the sensitivity parameter S from the sensor's technical specifications document. N (The unit is usually V / V or V / A, representing the ratio of the sensor's input physical quantity to its output electrical signal, such as the sensitivity S of a voltage sensor.) N =0.01V / V means that the sensor outputs a 0.01V electrical signal when the input voltage is 1V. According to the sensitivity parameter S N With the established power circuit measurement range, through formula V Sin =V A ×S N (where V) A V is a physical quantity within the measurement range of a power circuit. Sin Calculate the intensity range of the analog signal (for analog signal strength): using the power circuit measurement range of 0V-900V and the sensor sensitivity S... N Taking 0.01V / V as an example, the analog signal strength range is 0V×0.01V / V - 900V×0.01V / V, that is, 0V-9V, to ensure that after the analog signal is input into the sampling circuit, it can be equivalent to the sensor output signal corresponding to the real physical quantity in the power circuit.

[0044] Subsequently, a second step value is determined based on the calibration accuracy requirements (the smaller the step value, the higher the calibration accuracy; a step value of 0.05V-0.2V is usually selected, such as 0.1V). Starting from the minimum value of the analog signal intensity range (such as 0V), the intensity range is linearly increased according to the second step value to generate multiple analog sequence signals that increase sequentially. For example, when the analog signal intensity range is 0V-9V and the second step value is 0.1V, the generated analog sequence signals are 0V, 0.1V, 0.2V...9V.

[0045] Finally, the control signal generator inputs each analog sequence signal into the sampling circuit in sequence according to the generated analog sequence signal order. After receiving each analog signal, the sampling circuit samples and processes the analog signal according to the preset signal processing logic (such as adjusting the signal amplitude through the operational amplifier and superimposing the bias voltage), so as to provide the required sampling signal for the subsequent comparator circuit to determine the protection action and the DSP controller to calculate the digital signal.

[0046] This embodiment uses a signal generator or a regulated power supply connected to the input of the sampling circuit to simulate the actual measured quantity. The actual measured quantity and the simulated measured quantity satisfy the equation relationship between sensor input and output. A preset threshold voltage is generated by using a series resistor voltage divider. The signal generator is slowly adjusted to trigger the protection circuit, generating a high-level trigger signal, indicating a fault. At this time, the ADC reading Num of the DSP controller represents the actual protection threshold V. TH The "real VA + sensor" in the power circuit is replaced by an "analog signal VSi".

[0047] Step S103: Obtain a preset protection threshold, and correct the actual protection threshold according to the preset protection threshold and the target parameter.

[0048] It should be noted that, according to the aforementioned V Sen =V A x S N , and V sam =V Sen x K p + V p It can be deduced that the given trigger threshold voltage Vth corresponds to the actual protection threshold V in the power circuit. TH For V TH = (V th -V p ) / K p / S N .

[0049] In this embodiment, a preset protection threshold is first obtained from the device design parameters or control system (set at 1.3-1.5 times the device's rated value, such as an 840V overvoltage threshold corresponding to a 600V rated voltage). Combining the DSP target parameters (slope a, intercept b) of S101, the preset threshold is substituted into the correction formula (Num=a×physical quantity+b) to calculate the corresponding target digital signal.

[0050] When correcting the actual protection threshold, the signal generator can be controlled to adjust the analog signal so that the current digital signal obtained by the DSP based on the target parameters is equal to the target digital signal (i.e., the corresponding preset threshold). Then, the comparator trigger state is observed: if it is not triggered, the adjustable resistor of its voltage divider module is reduced (increased trigger threshold) until it is triggered; if it is triggered, the adjustable resistor is increased (decreased trigger threshold) until it is deactivated. Finally, the actual protection threshold is corrected to the preset protection threshold.

[0051] As an example of an embodiment of the present invention, the power electronic device further includes an indicator module and a programmable logic device. The indicator module includes a first LED and a second LED. The programmable logic device is connected to the comparator circuit and the DSP controller respectively, and is used to latch the trigger state of the protection action. The first LED is connected to the comparator circuit, and the second LED is connected to the programmable logic device. The protection threshold correction method further includes: When the comparator circuit triggers a protection action, it controls the first LED to turn on, latches the trigger state through the programmable logic device, and controls the second LED to turn on; the programmable logic device generates a fault signal and sends it to the DSP controller, which then controls the power circuit to stop outputting power; until the comparator circuit releases the protection action, it controls the first LED to turn off, while keeping the second LED on until a fault reset command is received, at which point the second LED is turned off.

[0052] In this embodiment, when the comparator circuit of the power electronic device detects that the current sampled signal is greater than its trigger threshold and triggers a protection action, since the first LED is directly connected to the comparator circuit, the high-level trigger signal output by the comparator circuit will directly control the first LED to turn on, thereby indicating in real time that the protection action has been triggered. At the same time, the programmable logic device (such as CPLD or FPGA) connected to the comparator circuit will synchronously receive the trigger signal of the protection action, and latch the current protection trigger state with its internal state latching function to avoid state loss due to the fast response speed of the protection action (microsecond level). After latching the trigger state, the programmable logic device will output a control signal to turn on the second LED, thereby realizing continuous indication of the protection trigger state.

[0053] Subsequently, the programmable logic device generates a fault signal based on the latched protection trigger state and transmits the fault signal to the DSP controller. After receiving the fault signal, the DSP controller immediately outputs a control command to the power circuit to cut off the voltage or current output path of the power circuit, so that the power circuit stops outputting power and prevents the power circuit from continuing to work under fault conditions, which could cause more serious device damage or safety accidents.

[0054] During subsequent calibration, when the comparator circuit detects that the current sampled signal is less than the trigger threshold and releases the protection action, the low-level signal output by the comparator circuit will directly control the first LED to turn off, indicating that the current protection action has been released. The programmable logic device, having already latched the protection trigger state, will continue to keep the second LED on until the staff has finished troubleshooting and sent a fault reset command through the device's fault reset interface (such as a physical reset button or remote control command). Only after receiving the reset command will the programmable logic device unlock the protection trigger state and control the second LED to turn off, completing the entire protection action indication and fault handling process.

[0055] As an example of an embodiment of the present invention, the comparator circuit further includes a reference voltage source and a voltage divider module. The voltage divider module includes an adjustable resistor and a fixed resistor. The trigger threshold is obtained by dividing the reference voltage output by the reference voltage source through the adjustable resistor. The correction of the actual protection threshold according to the preset protection threshold and the target parameter specifically involves: The intensity change state of the second analog signal is determined based on the actual protection threshold and the preset protection threshold; the signal generator is controlled to input multiple second analog signals to the sampling circuit for sampling based on the intensity change state; the current second digital signal is determined based on the target parameter and the current second sampling signal; when the physical quantity corresponding to the current second digital signal is equal to the preset protection threshold, the trigger threshold is updated by adjusting the adjustable resistor until the trigger state of the comparator circuit changes, at which point the actual protection threshold is corrected to the preset protection threshold.

[0056] In this embodiment, based on the relationship between the actual protection threshold and the trigger threshold, the following can be used: Figure 4 The flowchart shown illustrates the protection threshold correction method, which corrects the actual protection threshold. During the correction process, only the actual monitored quantity and the actual protection threshold, and their comparison results, are considered (e.g., when the monitored quantity V...). A =850V, actual protection threshold is V TH When = 840V, V A >V TH The protection function was triggered, trigger signal V oThe output is high and sent to the control unit, and the sampling signal V during the intermediate process is no longer considered. sam Or trigger threshold voltage V th How much exactly?

[0057] As an example of an embodiment of the present invention, the step of determining the intensity change state of the second analog signal based on the actual protection threshold and the preset protection threshold specifically includes: If the actual protection threshold is greater than the preset protection threshold, then the intensity of the analog signal corresponding to the current sampled signal is used as the initial signal intensity, and the initial signal intensity is decreased sequentially based on a preset step value to obtain each second analog signal; if the actual protection threshold is less than or equal to the preset protection threshold, then the intensity of the analog signal corresponding to the current sampled signal is used as the initial signal intensity, and the initial signal intensity is increased sequentially based on the preset step value to obtain each second analog signal.

[0058] As an example of an embodiment of the present invention, updating the trigger threshold by adjusting the resistance value of the adjustable resistor until the trigger state of the comparator circuit changes specifically involves: If the actual protection threshold is greater than the preset protection threshold, when the physical quantity corresponding to the current digital signal determined according to the target parameter is equal to the preset protection threshold, and the protection action of the comparator circuit is released, the resistance value of the adjustable resistor is controlled to decrease until the protection action of the comparator circuit is triggered; if the actual protection threshold is less than or equal to the preset protection threshold, when the physical quantity corresponding to the current digital signal determined according to the target parameter is equal to the preset protection threshold, and the protection action of the comparator circuit is triggered, the resistance value of the adjustable resistor is controlled to increase until the protection action of the comparator circuit is released.

[0059] In this embodiment, the comparator circuit first includes a reference voltage source (e.g., output 3V) and a voltage divider module composed of an adjustable resistor and a fixed resistor. The trigger threshold is set according to V. th =V ref× Adjustable resistor / (fixed resistor + adjustable resistor) (Vth is the trigger threshold voltage, Vref is the reference voltage) is obtained through voltage division. The change state of the second analog signal strength is determined by comparing the actual protection threshold with the preset protection threshold: when the actual value is greater than the preset value, the analog signal strength triggered by S102 is used as the initial value, and it is generated by decreasing by a preset amplitude (e.g., 0.1V); when the actual value is less than or equal to the preset value, it is generated by increasing by this initial value. The control signal generator inputs the second analog signal into the sampling circuit one by one. The sampling circuit generates the current second sampling signal according to the S101 logic (operational amplifier scaling + bias voltage superposition) and transmits it to the DSP. Based on the target parameters (slope a, intercept b), the DSP converts the current second sampling signal through the ADC to obtain the original ADC reading, and converts the original ADC reading into a first digital signal according to the initial parameters. Finally, the first digital signal is combined with the target parameters a and b obtained from the aforementioned fitting calculation, and the current second digital signal and its corresponding physical quantity are calculated using the formula: current second digital signal = a × first digital signal + b. Adjust the adjustable resistor until the physical quantity equals the preset protection threshold; if the actual value is greater than the preset value, decrease the adjustable resistor (increase V). th The comparator triggers protection; when the actual value is less than or equal to the preset value, the adjustable resistor is increased (V is decreased). th The comparator is deactivated, and the actual protection threshold is corrected to the preset value.

[0060] like Figure 5 As shown, based on the above method embodiments, corresponding system embodiments are provided; An embodiment of the present invention provides a protection threshold correction system 500 applied to a power electronic device; the power electronic device includes: a power circuit, a measurement circuit, a comparator circuit, a DSP controller, and a signal generator; wherein, the power circuit, the measurement circuit, and the comparator circuit are connected in sequence, and the sampling circuit in the measurement circuit is connected to the DSP controller and the signal generator respectively; the protection threshold correction system 500 includes: a measurement correction module 501, an actual threshold module 502, and a threshold correction module 503; The measurement correction module 501 is used to control the measurement circuit to measure the first reference physical quantity in the power circuit, obtain multiple first sampling signals output by the measurement circuit, process each first sampling signal through the initial parameters of the DSP controller to obtain multiple first digital signals, and perform fitting calculation on each first reference physical quantity and the corresponding first digital signal to obtain the target parameters of the DSP controller. The actual threshold module 502 is used to control the signal generator to input multiple analog signals to the sampling circuit for sampling. When the comparator circuit determines that the current sampled signal is greater than the trigger threshold of the comparator circuit, it triggers a protection action. Based on the target parameter and the current sampled signal, the DSP controller determines the current digital signal and uses the physical quantity corresponding to the current digital signal as the actual protection threshold. The threshold correction module 503 is used to obtain a preset protection threshold and correct the actual protection threshold according to the preset protection threshold and the target parameter.

[0061] It is understood that the above system embodiments correspond to the method embodiments of the present invention, and can implement the protection threshold correction method provided by any of the above method embodiments of the present invention.

[0062] It should be noted that the system embodiments described above are merely illustrative, and some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the system embodiments provided by this invention, the connection relationships between modules indicate that they have communication connections, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0063] For ease of description and brevity, the system embodiments of the present invention include all the implementation methods described in the above embodiments of the UAV-based information recognition method, and will not be repeated here.

[0064] Based on the above-described embodiments of the protection threshold correction method, another embodiment of the present invention provides a terminal device, which includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the protection threshold correction method of any embodiment of the present invention.

[0065] For example, in this embodiment, the computer program can be divided into one or more modules, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules may be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program in the terminal device.

[0066] The terminal device may be a desktop computer, laptop, handheld computer, or cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0067] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the terminal device, connecting all parts of the terminal device via various interfaces and lines.

[0068] Based on the above-described method embodiments, another embodiment of the present invention provides a computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to execute the protection threshold correction method described in any of the above-described method embodiments of the present invention.

[0069] The modules / units integrated in the device / terminal equipment, if implemented as software functional units and sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0070] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A protection threshold correction method, characterized in that, This method is applied to power electronic devices; the power electronic device includes: a power circuit, a measurement circuit, a comparator circuit, a DSP controller, and a signal generator; wherein the power circuit, the measurement circuit, and the comparator circuit are connected in sequence, and the sampling circuit in the measurement circuit is connected to the DSP controller and the signal generator respectively; the protection threshold correction method includes: The measurement circuit is controlled to measure the first reference physical quantity in the power circuit to obtain multiple first sampling signals output by the measurement circuit. The initial parameters of the DSP controller are then used to process each first sampling signal to obtain multiple first digital signals. The first reference physical quantity and the corresponding first digital signal are fitted and calculated to obtain the target parameters of the DSP controller. The signal generator is controlled to input multiple analog signals to the sampling circuit for sampling. When the comparator circuit determines that the current sampled signal is greater than the trigger threshold of the comparator circuit, a protection action is triggered. Based on the target parameter and the current sampled signal, the DSP controller determines the current digital signal and uses the physical quantity corresponding to the current digital signal as the actual protection threshold. Obtain a preset protection threshold, and correct the actual protection threshold based on the preset protection threshold and the target parameter.

2. The protection threshold correction method as described in claim 1, characterized in that, The comparator circuit further includes a reference voltage source and a voltage divider module. The voltage divider module includes an adjustable resistor and a fixed resistor. The trigger threshold is obtained by dividing the reference voltage output from the reference voltage source using the adjustable resistor. The correction of the actual protection threshold based on the preset protection threshold and the target parameter specifically involves: The intensity change state of the second analog signal is determined based on the actual protection threshold and the preset protection threshold; Based on the intensity change state, the signal generator is controlled to input multiple second analog signals to the sampling circuit for sampling; The current second digital signal is determined based on the target parameters and the current second sampling signal. When the physical quantity corresponding to the current second digital signal is equal to the preset protection threshold, the trigger threshold is updated by adjusting the adjustable resistor until the trigger state of the comparator circuit changes, at which point the actual protection threshold is corrected to the preset protection threshold.

3. The protection threshold correction method as described in claim 2, characterized in that, The determination of the intensity change state of the second analog signal based on the actual protection threshold and the preset protection threshold specifically involves: If the actual protection threshold is greater than the preset protection threshold, then the intensity of the analog signal corresponding to the current sampled signal is used as the initial signal intensity, and the initial signal intensity is decreased sequentially based on a preset step value to obtain each second analog signal; If the actual protection threshold is less than or equal to the preset protection threshold, then the intensity of the analog signal corresponding to the current sampled signal is used as the initial signal intensity, and the initial signal intensity is increased sequentially based on the preset step value to obtain each second analog signal.

4. The protection threshold correction method as described in claim 3, characterized in that, The step of updating the trigger threshold by adjusting the resistance value of the adjustable resistor until the trigger state of the comparator circuit changes is specifically as follows: If the actual protection threshold is greater than the preset protection threshold, when the physical quantity corresponding to the current digital signal determined according to the target parameter is equal to the preset protection threshold, and the protection action of the comparator circuit is released, the resistance value of the adjustable resistor is controlled to decrease until the protection action of the comparator circuit is triggered. If the actual protection threshold is less than or equal to the preset protection threshold, when the physical quantity corresponding to the current digital signal determined according to the target parameter is equal to the preset protection threshold, and the protection action of the comparator circuit is triggered, the resistance value of the adjustable resistor is increased until the protection action of the comparator circuit is released.

5. The protection threshold correction method as described in claim 1, characterized in that, The measurement circuit in the power electronic device further includes a sensor, and the control of the signal generator to input multiple analog signals to the sampling circuit for sampling is specifically as follows: Determine the measurement range of the power circuit; The sensitivity parameters of the sensor are obtained, and the intensity range of each analog signal is calculated based on the sensitivity parameters and the measurement range. A second step value is obtained, and the intensity range is linearly increased based on the second step value to obtain a plurality of analog sequence signals that increase sequentially. Each of the analog sequence signals is then input into the sampling circuit sequentially.

6. The protection threshold correction method as described in claim 1, characterized in that, The power electronic device further includes an indicator module and a programmable logic device. The indicator module includes a first LED and a second LED. The programmable logic device is connected to the comparator circuit and the DSP controller, respectively, for latching the trigger state of the protection action. The first LED is connected to the comparator circuit, and the second LED is connected to the programmable logic device. The protection threshold correction method further includes: When the comparator circuit triggers a protection action, it controls the first LED to turn on, latches the trigger state through the programmable logic device, and controls the second LED to turn on. The programmable logic device generates a fault signal and sends it to the DSP controller, which then controls the power circuit to stop outputting power. When the comparator circuit deactivates its protection mechanism, the first LED is turned off, while the second LED remains on until a fault reset command is received, at which point the second LED is turned off.

7. The protection threshold correction method as described in claim 5, characterized in that, The sampling circuit in the power electronic device includes an operational amplifier and a bias voltage source. The first sampling signal is determined based on the bias voltage output by the bias voltage source and the scaling factor of the operational amplifier, specifically: Acquire the sensor signal output by the sensor; scale the sensor signal according to the scaling factor, and superimpose the bias voltage to obtain the sampled signal.

8. A protection threshold correction system, applied to a power electronic device; the power electronic device comprising: The system comprises a power circuit, a measurement circuit, a comparator circuit, a DSP controller, and a signal generator; wherein the power circuit, measurement circuit, and comparator circuit are connected in sequence, and the sampling circuit in the measurement circuit is connected to the DSP controller and the signal generator respectively; the protection threshold correction system includes: a measurement correction module, an actual threshold module, and a threshold correction module; The measurement correction module is used to control the measurement circuit to measure the first reference physical quantity in the power circuit, obtain multiple first sampling signals output by the measurement circuit, process each first sampling signal through the initial parameters of the DSP controller to obtain multiple first digital signals, and perform fitting calculation on each first reference physical quantity and the corresponding first digital signal to obtain the target parameters of the DSP controller. The actual threshold module is used to control the signal generator to input multiple analog signals to the sampling circuit for sampling. When the comparator circuit determines that the current sampled signal is greater than the trigger threshold of the comparator circuit, it triggers a protection action. Based on the target parameter and the current sampled signal, the DSP controller determines the current digital signal and uses the physical quantity corresponding to the current digital signal as the actual protection threshold. The threshold correction module is used to obtain a preset protection threshold and correct the actual protection threshold according to the preset protection threshold and the target parameter.

9. A terminal device, characterized in that, It includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, it implements the protection threshold correction method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, include: A stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the protection threshold correction method as described in any one of claims 1-7.

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