Automobile rectifier overcurrent protection method and system based on current feedback

Abstract

The application provides a current feedback-based overcurrent protection method and system for an automobile rectifier, and relates to the technical field of rectifier protection, wherein the method comprises the following steps: obtaining an access circuit of the rectifier through a control isolation storage area in an integrated circuit, equivalently processing the access circuit according to the working condition scene of the rectifier, determining a scene circuit and storing the scene circuit in the storage area, collecting current data of a key position pair in the scene circuit, determining an overcurrent condition and generating a protection trigger instruction, activating an intelligent decision maker embedded in the control in the integrated circuit according to the protection trigger instruction, executing parallel decision of a soft protection response and a rigid protection response, determining an overcurrent protection strategy, and performing overcurrent protection management on the access circuit. The technical problem that the automobile rectifier cannot be accurately and effectively protected in the prior art is solved. The technical effects of improving the pertinence, accuracy and reliability of the overcurrent protection strategy of the rectifier and improving the safety of vehicle operation are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rectifier protection, and particularly relates to a current feedback-based automobile rectifier overcurrent protection method and system. BACKGROUND

[0002] The automobile rectifier is a device commonly used in automobile electrical systems, and its main function is to convert the alternating current generated by the generator into direct current, charge the battery, and meet the power needs of various electronic devices on the vehicle. When the automobile is idling, the rectifier can effectively reduce the engine's jitter, making the vehicle run more smoothly and improving the power performance. In addition, the rectifier can also protect the battery and the original vehicle circuit system, reduce their work load, and prolong their service life.

[0003] However, in actual operation, due to short circuit, load mutation or other electrical faults, the automobile rectifier may appear overcurrent phenomenon. Once overcurrent occurs, if it cannot be handled in time and effectively, it will cause serious damage to the rectifier itself and the entire automobile electrical system. At present, common overcurrent protection methods include fuse protection, thermistor protection and electronic overcurrent protection circuit, but these overcurrent protection technologies can provide protection to some extent, but they have deficiencies in reliability, pertinence and stability.

[0004] The prior art has the technical problem of insufficient reliability and pertinence of automobile rectifier overcurrent protection measures, which causes the rectifier to be unable to be accurately and effectively protected when overcurrent occurs, affecting the safety and stability of vehicle operation. SUMMARY

[0005] The purpose of the present application is to provide a current feedback-based automobile rectifier overcurrent protection method and system, which solves the technical problem of insufficient reliability and pertinence of automobile rectifier overcurrent protection measures in the prior art, which causes the rectifier to be unable to be accurately and effectively protected when overcurrent occurs, affecting the safety and stability of vehicle operation.

[0006] In view of the above problems, the present application provides a current feedback-based automobile rectifier overcurrent protection method and system.

[0007] In a first aspect of the present application, a current feedback-based overcurrent protection method for an automobile rectifier is provided, the method comprising: controlling an isolation storage area in an integrated circuit, obtaining an access circuit of the rectifier, according to a working condition scenario of the rectifier, performing equivalent on the access circuit, determining a scenario circuit and storing the scenario circuit in the storage area, wherein a differential equivalent mode is adopted, and the scenario circuit identifies a key position pair; collecting current data of the key position pair in the scenario circuit, determining an overcurrent condition and generating a protection trigger instruction by performing time-frequency analysis, wherein the overcurrent condition includes an overcurrent type; according to the protection trigger instruction, activating an intelligent decision maker embedded in the integrated circuit control, performing parallel decision of soft protection response and rigid protection response for the overcurrent condition, and determining an overcurrent protection strategy; and performing overcurrent protection management on the access circuit according to the overcurrent protection strategy.

[0008] Optionally, according to the working condition scenario, positioning a steady-state access element and a fluctuation access element; for the access circuit, performing differential equivalent processing based on the circuit topology of the steady-state access element and the fluctuation access element, and determining the scenario circuit; and storing the scenario circuit to the integrated circuit control.

[0009] Optionally, for the fluctuation access element, determining a first fluctuation part and a second fluctuation part; processing the access circuit by maintaining the circuit topology of the first fluctuation part, performing non-complete equivalent on the circuit topology of the second fluctuation part, and performing complete equivalent on the circuit topology of the steady-state access element, and determining the scenario circuit; and for the working condition scenario, identifying a key position pair in the scenario circuit, wherein one key position pair includes a first remote end and a second near end, and the key position pair is a current feedback point.

[0010] Optionally, determining a first key position pair, wherein the first key position pair is any group of first remote end and second near end in the key position pair; according to current acceleration, determining a slope vector, performing dynamic out-of-limit judgment and mutual test on the first key position pair, and determining a first judgment result; according to current value, performing out-of-limit judgment and mutual test based on current threshold on the first key position pair, and determining a second judgment result; and if at least one of the first judgment result and the second judgment result is met, determining an overcurrent condition by performing overcurrent type judgment.

[0011] Optionally, performing transient overcurrent judgment by taking a sudden surge of high-frequency component as a judgment feature, and determining a first overcurrent type, wherein the first overcurrent type is a transient surge state; performing steady-state overload judgment by taking a sustained out-of-limit of low-frequency current as a judgment feature, and determining a second overcurrent type, wherein the second overcurrent type is a sustained short-circuit state; and wherein if the second judgment result is met, the first overcurrent type or the second overcurrent type is determined in combination with the first judgment result.

[0012] Optionally, if the second determination result is not met, the first determination result is met, a third pre-overcurrent type is determined according to the abnormality of the slope vector, and the third pre-overcurrent type is a pre-warning state.

[0013] Optionally, a first decision channel is deployed for a soft protection response, the soft protection response is in the form of a step-by-step duty cycle reduction; a second decision channel is deployed for a rigid protection response, the rigid protection response is in the form of shutdown; and the first decision channel and the second decision channel are parallel, and are trained to convergence by supervision, as the intelligent decision maker.

[0014] Optionally, according to the protection trigger instruction, the intelligent decision maker is activated, parallel decision based on the first decision channel and the second decision channel is performed for the overcurrent condition, a first strategy and a second strategy are determined; if the first strategy is a non-empty set, the first strategy is taken as the overcurrent protection strategy; if the first strategy is an empty set, the second strategy is taken as the overcurrent protection strategy.

[0015] Optionally, the overcurrent condition is priori, and it is determined whether it is a first inducement, the first inducement refers to element failure or branch failure; if it is the first inducement, the faulty circuit topology is isolated by shutdown control of the circuit breaker.

[0016] In a second aspect of the present application, a current feedback-based overcurrent protection system for an automobile rectifier is provided, the system comprising: a circuit equivalence module for controlling an isolation storage area in an integrated circuit, acquiring an access circuit of a rectifier, equivalencing the access circuit according to working condition scenarios of the rectifier, determining a scenario circuit and storing it in the built-in storage area, wherein a differential equivalence mode is adopted, and the scenario circuit identifies a key position pair; a data analysis module for collecting current data of the key position pair in the scenario circuit, determining an overcurrent condition and generating a protection trigger instruction by performing time-frequency analysis, wherein the overcurrent condition includes an overcurrent type; a protection strategy determination module for activating an intelligent decision maker embedded in the integrated circuit controlled by the integrated circuit according to the protection trigger instruction, performing parallel decision of a soft protection response and a rigid protection response for the overcurrent condition, and determining an overcurrent protection strategy; and an overcurrent protection management module for performing overcurrent protection management on the access circuit according to the overcurrent protection strategy.

[0017] One or more technical solutions provided in the present application have at least the following technical effects or advantages:

[0018] The method provided by the embodiment of the application controls the isolation storage area in the integrated circuit, obtains the access circuit of the rectifier, performs equivalent on the access circuit according to the working condition scene of the rectifier, determines the scene circuit and stores the scene circuit in the built-in storage area, wherein the differential equivalent mode is adopted, the scene circuit is identified in relation to a key position pair; current data of the key position pair in the scene circuit is collected, time-frequency analysis is performed, an overcurrent condition is determined, and a protection trigger instruction is generated, wherein the overcurrent condition includes an overcurrent type; according to the protection trigger instruction, the intelligent decision maker embedded in the integrated circuit control is activated, parallel decision of the soft protection response and the rigid protection response is performed for the overcurrent condition, and an overcurrent protection strategy is determined; and the access circuit is managed according to the overcurrent protection strategy. The technical effect of improving the pertinence and reliability of the overcurrent protection strategy of the rectifier is achieved, and the safety and stability of vehicle operation are improved.

[0019] The above description is only a summary of the technical solutions of the application. In order to enable the technical means of the application to be more clearly understood, the following detailed description can be implemented according to the content of the specification, and in order to enable the above and other purposes, characteristics and advantages of the application to be more obvious and easy to understand, the following detailed description of the application is given. It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the application, nor is it intended to limit the scope of the application. Other features of the application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only exemplary, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0021] Figure 1 The flowchart of the automobile rectifier overcurrent protection method based on current feedback provided by the application is shown.

[0022] Figure 2 The structural schematic diagram of the automobile rectifier overcurrent protection system based on current feedback provided by the application is shown.

[0023] Explanation of reference signs: circuit equivalent module 11, data analysis module 12, protection strategy determination module 13, overcurrent protection management module 14. DETAILED DESCRIPTION

[0024] This application provides a current feedback-based overcurrent protection method and system for automotive rectifiers, addressing the technical problem that existing overcurrent protection measures for automotive rectifiers lack reliability and specificity, resulting in inaccurate and ineffective protection of the rectifier during overcurrent, thus affecting vehicle operational safety and stability. It achieves the technical effect of improving the specificity and reliability of the rectifier overcurrent protection strategy, thereby enhancing the safety and stability of vehicle operation.

[0025] The technical solutions of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. It should be understood that the present invention is not limited to the exemplary embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. It should also be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0026] Example 1, as Figure 1 As shown, this application provides an overcurrent protection method for automotive rectifiers based on current feedback, the method comprising:

[0027] In the integrated circuit control isolation storage area, the rectifier access circuit is obtained. According to the rectifier's operating conditions, the access circuit is equivalent, the scenario circuit is determined and stored in the storage area. The differential equivalent mode is adopted, and the scenario circuit is marked with key position pairs.

[0028] Specifically, first, the access circuit of the rectifier is obtained in the integrated circuit control isolation storage area. The integrated circuit control isolation storage area is integrated in the control chip, used for storing data related to control logic, and has an isolation function to prevent external interference from affecting the accuracy of stored data. In the integrated circuit control isolation storage area, the access circuit of the rectifier is identified by analyzing the circuit topology of the rectifier and the external circuit connection. The access circuit of the rectifier refers to all circuit parts connected to the outside in the actual working state of the rectifier, including power input circuit, load output circuit and bypass circuit, etc. Then, according to the working condition scene of the rectifier, the access circuit is equivalent by using the differential equivalent mode. The working condition scene is various states faced by the rectifier in the process of automobile running, such as cold start, high load, voltage fluctuation, etc. The differential equivalent mode is a method of equivalent processing by comparing the electrical parameter differences of different nodes or branches in the circuit. Specifically, the complex topology structure in the access circuit is decomposed into multiple basic differential units, each unit representing a certain electrical characteristic in the circuit. For example, for a circuit containing multiple resistors and capacitors, the differential equivalent mode can decompose it into multiple simple RC (resistor-capacitor) differential units, and the parameters of each unit are obtained by measurement or calculation, thereby realizing the simplified representation of the entire circuit. After the differential equivalent processing of the access circuit is completed, the scene circuit of the actual access circuit in the specific working condition is obtained, which is a precise and simplified representation. The scene circuit identifies the key position pair, which can reflect the distribution and change of current in the scene circuit, and can timely find the abnormal current change in the circuit, thereby providing accurate basis for overcurrent protection. Finally, the determined scene circuit data is stored in the integrated circuit control isolation storage area, ensuring the reliability and stability of the collected data.

[0029] Further, according to the working condition scene of the rectifier, the access circuit is equivalent, including: according to the working condition scene, locating the steady-state access element and the fluctuation access element; for the access circuit, performing differential equivalent processing based on the circuit topology of the steady-state access element and the fluctuation access element, determining the scene circuit; storing the scene circuit to the integrated circuit control.

[0030] Specifically, the working condition scene refers to various actual situations faced by the rectifier during the operation of the automobile, such as cold start, high load, and voltage fluctuation. Under different working condition scenes, the current change characteristics are different, the current threshold for triggering overload protection also has differences, and the equivalent parts of the circuit also have differences. For example, a certain element behaves as a steady-state element in one scene, and its electrical parameters remain basically unchanged, while in another scene, it may become a non-steady-state element, and its parameters will change over time or external conditions. For a working condition scene, such as the cold start condition, first locate the steady-state access element and the fluctuation access element. The steady-state access element is an element whose electrical characteristics, such as resistance, capacitance, inductance, etc., remain basically stable under the current working condition scene, and it plays a role in stabilizing voltage and current in the circuit. The fluctuation access element is an element whose electrical characteristics change significantly over time or external conditions under the current working condition scene. For example, during cold start, due to temperature changes and unstable engine speed, the capacitance of some capacitors may fluctuate. During the process of locating the two elements, parameters such as voltage across the element and current flowing through the element can be measured, and the running characteristics of the rectifier can be analyzed and judged.

[0031] Then, based on the equivalent method of circuit difference principle, the access circuit is processed by analyzing the different roles and mutual relationships of the steady-state access element and the fluctuation access element in the circuit. For example, a simulation model of the access circuit is established using circuit simulation software such as Multisim, PSpice, etc. The corresponding parameters are set according to the characteristics of the steady-state access element and the fluctuation access element, and the response of the circuit under different conditions is simulated and analyzed. The equivalent model is continuously adjusted so that the access circuit is simplified to an equivalent circuit with corresponding electrical characteristics. After the differential equivalent processing, the scene circuit is determined, which is a precise and simplified representation of the access circuit under the current working condition scene. The scene circuit retains the key electrical characteristics of the actual circuit under the cold start condition. Finally, the determined scene circuit is stored in the integrated circuit control, which can be quickly called and analyzed in the subsequent overcurrent protection process, improving the accuracy and timeliness of overcurrent protection.

[0032] Further, the differential equivalent processing based on the circuit topology of the steady-state access element and the fluctuation access element is performed, including: for the fluctuation access element, determining a first fluctuation part and a second fluctuation part; maintaining the circuit topology of the first fluctuation part, non-fully equivalent to the circuit topology of the second fluctuation part, and fully equivalent to the circuit topology of the steady-state access element, processing the access circuit to determine the scene circuit; for the working condition scene, identifying a key position pair in the scene circuit, where a key position pair contains a first far end and a second near end, and the key position pair is a current feedback point.

[0033] Specifically, in the differential equivalent processing of the circuit topologies of the steady-state access elements and the fluctuation access elements, high-precision circuit test instruments such as high-resolution oscilloscopes and LCR testers are used to analyze the fluctuation access elements first to determine the first-order fluctuation part and the second-order fluctuation part. The first-order fluctuation part is the part of the fluctuation access element with a larger fluctuation amplitude and a greater impact on the overall characteristics of the circuit, such as a large change in the capacitance value within a short time. The second-order fluctuation part is the part of the fluctuation access element with a relatively small fluctuation amplitude and a smaller impact on the circuit. Then, differential equivalent processing is performed. The circuit topology of the first-order fluctuation part is maintained, and the connection mode and the basic structure of the first-order fluctuation part in the original access circuit are retained. The circuit topology of the second-order fluctuation part is processed in a non-fully equivalent manner, i.e., simplified or approximated, such as a small capacitance change of a capacitor, which can be equivalent to a fixed capacitor in parallel with a small variable capacitor, reducing the complexity of the circuit while retaining its basic response characteristics to current changes. The circuit topology of the steady-state access element is fully equivalent, such as a fixed resistance, which is required to be fully consistent with the original resistance in the equivalent process. Through the above processing method, the access circuit is equivalent processed to obtain a scene circuit corresponding to the current working condition scene. In the scene circuit, a plurality of key position pairs are identified according to the topology of the circuit and the actual operating characteristics of the current working condition scene. A key position pair includes a first remote end and a second near end. The first remote end refers to a position in the circuit that is relatively far from the power supply or signal input end, which can reflect the overall current state of the circuit. The second near end refers to a position that is relatively close to the power supply or signal input end, which is used to monitor local current changes. The key position pair is a current feedback point. By collecting current signals at these key positions, the current changes in the circuit can be monitored in real time. For example, in the high-load working condition of the automobile rectifier, by collecting the current at the key position pair, it can be determined whether the current is abnormal in time, thereby triggering the overcurrent protection mechanism.

[0034] Through differential equivalent processing based on steady-state and fluctuation access elements, the circuit can be accurately simplified according to different working condition scenes, which not only retains the key characteristics of the circuit but also reduces the complexity of subsequent analysis and processing. By identifying the key position pairs in the scene circuit, the accuracy and reliability of the overcurrent protection are improved, thereby ensuring the safe and stable operation of the automobile rectifier and improving the reliability of the entire automobile electrical system.

[0035] The current data of the key position pairs in the scene circuit are collected, and time-frequency analysis is performed to determine the overcurrent condition and generate a protection trigger instruction. The overcurrent condition includes an overcurrent type.

[0036] Specifically, a high-precision current sensor, such as a Hall current sensor, is used to collect current data of key position pairs in the scene circuit in real time, and the current data of the key position pairs are obtained. Then, time-frequency analysis methods, such as short-time Fourier transform and wavelet transform, are used to analyze the collected current data. For example, the short-time Fourier transform is used to divide the current data signal into multiple short time periods, and the Fourier transform is performed on each time period to obtain the frequency spectrum information of the signal in each time period. According to the time-frequency analysis result, the overcurrent condition is determined, which includes the overcurrent type, such as the persistent overcurrent caused by low-frequency large current due to sudden load increase or circuit short circuit fault, or the transient overcurrent caused by high-frequency harmonic. The frequency and amplitude information obtained by time-frequency analysis are comprehensively judged. Further, according to the overcurrent condition, a protection trigger instruction is generated to protect the rectifier. By collecting the current data of the key position pairs and using time-frequency analysis technology to analyze the characteristics of the current signal, the overcurrent condition and its type can be accurately and timely determined, providing a reliable basis for generating an effective protection trigger instruction, thereby improving the accuracy and timeliness of overcurrent protection, effectively avoiding damage to the rectifier caused by overcurrent, ensuring the stable operation of the automobile electrical system, and improving the overall safety and reliability of the automobile.

[0037] Further, by performing time-frequency analysis, the overcurrent condition is determined, including: determining a first key position pair, wherein the first key position pair is any group of first remote end and second near end in the key position pairs; determining a slope vector according to the current acceleration, performing dynamic out-of-limit judgment and mutual test on the first key position pair to determine a first determination result; performing out-of-limit judgment and mutual test on the first key position pair based on the current threshold to determine a second determination result; if at least one of the first determination result and the second determination result is satisfied, the overcurrent condition is determined by performing overcurrent type determination.

[0038] Specifically, from any optional set of first and second ends of the plurality of key position pairs as a first key position pair, and using a high-precision current sensor to collect current data of the first key position pair, and calculating the rate of change of current in unit time through a differential algorithm to obtain current acceleration, which reflects the speed of current change. According to the direction and size of the current acceleration, the slope vector of the current change is calculated, and according to the slope vector, the trend and speed of the current change can be judged. Then, dynamic out-of-limit judgment is performed on the first key position pair. The dynamic threshold is set according to different working conditions of the rectifier, which is dynamically adjusted to adapt to various changes in actual operation. By comparing the slope vector with the dynamic threshold, it is judged whether the current change is out of the normal range. If the slope vector abnormally increases, it indicates that the current change is too fast, and there may be a risk of instantaneous overcurrent. Mutual verification is performed on the first and second ends of the same key position pair, and the consistency of the results is compared to ensure the accuracy of the judgment and avoid misjudgment caused by measurement error or local interference. According to the dynamic out-of-limit judgment and mutual verification results, the first judgment result is obtained.

[0039] According to the current value, the out-of-limit judgment and mutual verification based on the current threshold are performed on the first key position pair. The current threshold is determined through experiments and theoretical analysis, which represents the maximum allowed value of the current in the normal working state. When the actual current exceeds this threshold, it indicates that the circuit may be in an overcurrent state. The current value of the first key position pair is monitored to determine whether it exceeds the current threshold, and mutual verification is also performed to obtain the second judgment result. When at least one of the first and second judgment results is met, it indicates that there is an overcurrent condition, and further overcurrent type judgment is performed to determine the overcurrent condition, so as to take corresponding protection measures. Through time-frequency analysis and multi-dimensional judgment method, the overcurrent condition and type can be quickly and accurately identified, thereby providing reliable data support for subsequent intelligent decision and protection measures, improving the response speed and accuracy of overcurrent protection, effectively preventing the damage of the rectifier caused by overcurrent, and ensuring the safe operation of the automobile electrical system.

[0040] Further, overcurrent type judgment is performed, including: taking the sudden increase of high-frequency component as the judgment feature to perform instantaneous overcurrent judgment to determine the first overcurrent type, wherein the first overcurrent type is instantaneous surge state; taking the continuous out-of-limit of low-frequency current as the judgment feature to perform steady-state overload judgment to determine the second overcurrent type, wherein the second overcurrent type is continuous short-circuit state; wherein if the second judgment result is met, the first overcurrent type or the second overcurrent type is determined in combination with the first judgment result.

[0041] Further, if the second determination result is not satisfied, the first determination result is satisfied, and the third pre-overcurrent type is determined based on the abnormality of the slope vector, where the third pre-overcurrent type is a pre-warning state.

[0042] Specifically, in the current signal, the high-frequency component is related to transient phenomena in the circuit, such as short circuit, transient switching action of components, etc. Therefore, in the overcurrent type determination process, the sudden increase of the high-frequency component is used as a determination feature for transient overcurrent determination. Through time-frequency analysis technology, the collected current signal is decomposed into different frequency bands. When the amplitude of the high-frequency component is suddenly increased by a large margin and exceeds the set high-frequency threshold, it is determined as a transient overcurrent, and the first overcurrent type is determined as a transient surge state. The transient surge state refers to a sharp rise of current in a short time. This overcurrent type is mostly caused by external sudden disturbance or internal transient process of the circuit. Its characteristic is short duration, but the current amplitude may reach a very high value in an instant. If not handled in time, it may cause damage to sensitive components in the rectifier.

[0043] Then, the continuous over-limit of the low-frequency current is used as a determination feature for steady-state overload determination. The low-frequency current reflects the main energy transmission in the circuit. When the circuit has a continuous short circuit or the load is seriously overloaded, the low-frequency current will exceed the set low-frequency current threshold for a long time. By setting the low-frequency current threshold, if the low-frequency current continuously exceeds the low-frequency current threshold for a period of time, it is determined that the overcurrent type is steady-state overload, and the second overcurrent type is determined as a continuous short circuit state. The continuous short circuit state refers to a continuous overcurrent that exceeds the preset threshold. If not handled in time, it may cause the rectifier to overheat or even be damaged.

[0044] In the overcurrent type determination, the first determination result and the second determination result are combined for judgment. When the current meets the second determination result, the first determination result is combined to determine whether the current overcurrent condition is the first overcurrent type or the second overcurrent type based on the above judgment method. Specifically, if the second determination result shows that the current value continuously exceeds the threshold, and the first determination result shows that the current acceleration change meets the continuous short circuit characteristics, it is determined as a continuous short circuit state. If the second determination result shows that the current value exceeds the threshold instantaneously, and the first determination result shows that the current acceleration change meets the transient surge characteristics, it is determined as a transient surge state. However, whether the first overcurrent type or the second overcurrent type is an overcurrent protection condition, but further determines the specific state through judgment, and then takes appropriate protection measures according to different overcurrent conditions.

[0045] When it is judged that the current does not meet the second determination result and only meets the first determination result, that is, it is judged that the current rate of change is abnormal, such as the rate of change suddenly increases or the direction suddenly changes, but the current value does not reach the current threshold, it indicates that there may be potential risks in the circuit, that is, overcurrent will occur. According to the abnormality of the slope vector, a third overcurrent precursor type is determined, which is a precursor warning state. The precursor warning state refers to an abnormal current rate of change, although the current value does not exceed the threshold, but there is a potential overcurrent risk. In actual situations, overcurrent damage is often caused by a sudden increase in current, such as a short circuit. At the same time, for the current rate of change, when the slope is abnormal, intervention can be made in advance to take preventive measures such as reducing current or issuing an alarm before overcurrent occurs, thereby avoiding unnecessary downtime and equipment damage.

[0046] By determining the key positions, it can be determined whether the overcurrent response needs to be triggered and how to respond to the decision according to different overcurrent conditions, generate a protection trigger instruction, and maximize the reduction of unnecessary downtime under frequent shutdown, that is, false protection operation, maximize the impact on the normal operation of the automobile, and improve the reliability and practicality of the entire overcurrent protection scheme, further improving the overall operation efficiency and safety of the automobile electrical system.

[0047] According to the protection trigger instruction, the intelligent decision maker embedded in the integrated circuit control is activated, and parallel decision of soft protection response and rigid protection response is performed for the overcurrent condition to determine the overcurrent protection strategy.

[0048] According to the overcurrent protection strategy, the overcurrent protection management is performed on the access circuit.

[0049] Specifically, after generating the protection trigger instruction, the intelligent decision maker embedded in the integrated circuit control is activated according to the protection trigger instruction, and the intelligent decision maker includes a first decision channel of soft protection response and a second decision channel of rigid protection response. For the overcurrent condition, the intelligent decision maker executes parallel decision of soft protection response and rigid protection response through the parallel deployment of the first decision channel and the second decision channel. The soft protection response is implemented in a way of gradually reducing the duty cycle, and the duty cycle refers to the proportion of time that the signal is at a high level in a period. By gradually reducing the duty cycle, the output current of the rectifier can be smoothly reduced to avoid the impact of current mutation on the circuit and the load. The rigid protection response adopts the shutdown mode, and when the overcurrent condition is serious enough to cause irreversible damage to the rectifier, the output circuit of the rectifier is directly cut off to make the current instantaneously drop to zero, quickly and completely protecting the rectifier. It is often used for serious and continuous overcurrent conditions. By comprehensively analyzing the overcurrent condition, the final overcurrent protection strategy is determined.

[0050] Finally, based on the determined overcurrent protection strategy, the access circuit is managed for overcurrent protection. If the overcurrent protection strategy is a soft protection response, the integrated circuit control will send instructions to the circuit control module, and the control module will accurately adjust the duty cycle to gradually reduce the current output and avoid frequent interruptions. If the strategy is a rigid protection response, the control module will immediately cut off the circuit connection to prevent the current from continuing to flow. In this process, the circuit state is continuously monitored to ensure the effectiveness of the protection strategy.

[0051] Through the accurate decision of the intelligent decision maker and the fine protection management of the access circuit, the most suitable protection mode can be flexibly selected according to different overcurrent conditions, which not only effectively protects the rectifier and related circuits from overcurrent damage, but also avoids unnecessary downtime caused by excessive protection, thereby improving the reliability and stability of the overall operation of the automobile electrical system.

[0052] Further, before activating the intelligent decision maker embedded in the integrated circuit control, the construction of the intelligent decision maker includes: deploying a first decision channel for a soft protection response, wherein the soft protection response is in the form of gradually reducing the duty cycle; deploying a second decision channel for a rigid protection response, wherein the rigid protection response is in the form of turning off; and running the first decision channel and the second decision channel in parallel, and through supervised training to convergence, as the intelligent decision maker.

[0053] Specifically, the construction of the intelligent decision maker includes the deployment of a first decision channel for a soft protection response and the deployment of a second decision channel for a rigid protection response. Soft protection response refers to a gradual protection method that limits the size of the current by gradually reducing the duty cycle. Duty cycle refers to the ratio of the on-time of the circuit to the total time within a certain time. Gradually reducing the duty cycle means gradually reducing the on-time of the circuit, thereby reducing the current. Specifically, it can be achieved through pulse width modulation (PWM), and the PWM controller will gradually reduce the pulse width according to the overcurrent condition, thereby reducing the average current of the circuit. Soft protection method is suitable for overcurrent conditions such as transient surge, which is usually short-lived and does not immediately cause serious damage to the circuit. By gradually reducing the duty cycle, voltage spikes or other potential problems caused by sudden power cutoff can be avoided. Rigid protection response refers to a protection method that immediately cuts off the power supply to prevent the circuit from being damaged by continuous overcurrent. The rigid protection response method is suitable for serious overcurrent conditions such as continuous short circuit. The rigid protection response is achieved by quickly cutting off the circuit, and optionally, a high-speed switch such as MOSFET or IGBT is set in the circuit to achieve the cutting off of the circuit in a very short time. The first decision channel and the second decision channel are run in parallel, and real-time collected overcurrent condition data is analyzed and decided.

[0054] To ensure the accuracy and reliability of the intelligent decision maker, two decision channels are trained to convergence through supervision, for example, a large number of overcurrent condition data samples under different working conditions are collected, and multiple data samples include various possible overcurrent conditions, such as different degrees of transient overcurrent and continuous overcurrent. At the same time, each sample is labeled with a specific protection response mode, i.e. soft protection response or rigid protection response, to form a labeled training data set. For example, for transient overcurrent samples, soft protection response is labeled, and for severe continuous overcurrent samples, rigid protection response is labeled. The training data set is input into the algorithm models of the first decision channel and the second decision channel running in parallel. During the training process, the algorithm model adjusts its parameters according to the input overcurrent condition data and specific label data, and through multiple iterations of training, the performance of the model is gradually optimized to improve the accuracy of judgment of different overcurrent conditions. When the decision accuracy of the model reaches a threshold, such as 95% or more, and the accuracy no longer improves significantly, it means that the model has reached convergence, that is, the supervision training is completed, and the parallel decision channel model combination at this time is the constructed intelligent decision maker.

[0055] By deploying the decision channels of soft protection response and rigid protection response respectively, and using parallel running and supervision training, the intelligent decision maker can automatically and accurately select the most suitable protection strategy according to different overcurrent conditions, which can effectively protect the rectifier from overcurrent damage and avoid unnecessary downtime caused by overprotection, thereby improving the reliability and stability of the automobile electrical system.

[0056] Further, the parallel decision of soft protection response and rigid protection response is executed to determine the overcurrent protection strategy, including: according to the protection trigger instruction, activating the intelligent decision maker, executing parallel decision based on the first decision channel and the second decision channel for the overcurrent condition, and determining the first strategy and the second strategy; if the first strategy is a non-empty set, the first strategy is taken as the overcurrent protection strategy; if the first strategy is an empty set, the second strategy is taken as the overcurrent protection strategy.

[0057] Specifically, after receiving the protection trigger instruction, the integrated circuit control will immediately activate the embedded intelligent decision maker. The intelligent decision maker determines the first strategy and the second strategy based on the real-time obtained overcurrent condition and the parallel decision based on the first decision channel and the second decision channel. If the first strategy is a non-empty set, i.e., the soft protection response can solve the current overcurrent condition, the intelligent decision maker will take the first strategy as the overcurrent protection strategy, limit the current by gradually reducing the duty cycle, and avoid voltage spikes or other potential problems caused by sudden power cut-off. Only when the first strategy is an empty set and the soft protection response cannot meet the current overcurrent condition, the second strategy is taken as the overcurrent protection strategy, i.e., the power is immediately cut off to prevent circuit damage. The soft protection response has the first priority and can avoid frequent interruptions, minimize the impact on the normal operation of the vehicle under the premise of meeting the protection requirements. Only when the first strategy is empty and the soft protection cannot meet the current overcurrent condition, the second strategy is executed for rigid protection. Through the parallel decision mechanism, the soft protection and rigid protection responses can be analyzed and judged simultaneously, the overcurrent condition can be responded more quickly, unnecessary downtime under frequent interruptions can be reduced, the efficiency of overcurrent protection can be improved, and the overall operation efficiency and safety of the vehicle electrical system can be improved.

[0058] Further, after determining the overcurrent condition, the method further comprises: performing a priori on the overcurrent condition to determine whether it is a first inducement, wherein the first inducement refers to an element failure or a branch failure; if the first inducement, isolating the fault circuit topology by controlling the shutdown of the circuit breaker for the fault circuit topology.

[0059] Specifically, after determining the overcurrent condition, the overcurrent condition is diagnosed and analyzed according to a pre-set fault feature library and a diagnosis algorithm. The fault feature library stores various fault modes that can cause overcurrent and corresponding characteristic parameters thereof, such as the sudden change characteristic of current when a component fails, abnormal distribution of voltage and current when a branch fails, and the like. The diagnosis algorithm compares and matches the real-time collected current parameters with the data in the fault feature library, so as to determine whether the current overcurrent is caused by the first cause, i.e., component failure or branch failure. Component failure includes resistor burnout, capacitor breakdown, transistor damage, and the like. These faults can change the electrical performance of the component, thereby affecting the current distribution of the entire circuit and causing overcurrent. Branch failure includes line short circuit, open circuit, and the like. Short circuit can sharply reduce the resistance of the branch and greatly increase the current, and open circuit can cause the current of other branches to abnormally increase, thereby causing overcurrent. If it is determined that the overcurrent is caused by component failure or branch failure, i.e., the first cause, the faulty circuit topology is isolated. Specifically, according to the result of the fault diagnosis algorithm, the specific position of the fault is determined, and the isolation of the faulty circuit topology is realized through the shutdown of the circuit breaker. For example, if it is detected that a short circuit fault exists in a branch, the power supply of the branch is cut off through the circuit breaker, so as to prevent the fault from further expanding and affecting other normally operating components and branches.

[0060] By priori overcurrent condition, it can be quickly and accurately determined whether the overcurrent is caused by component failure or branch failure, and the faulty circuit topology is isolated in time through the shutdown control of the circuit breaker, so as to prevent the fault from further expanding, protect other normal components and branches from being damaged, and improve the reliability and stability of the entire automobile circuit system.

[0061] Embodiment two, based on the same inventive concept as the current feedback-based automobile rectifier overcurrent protection method in the foregoing embodiments, as shown in Figure 2 The application provides a current feedback-based automobile rectifier overcurrent protection system, wherein the current feedback-based automobile rectifier overcurrent protection system comprises:

[0062] The circuit equivalent module 11 is used for controlling the isolation storage area in the integrated circuit, obtaining the access circuit of the rectifier, performing equivalent on the access circuit according to the working condition scene of the rectifier, determining the scene circuit and storing the embedded storage area, wherein the differential equivalent mode is adopted, and the scene circuit identifies the key position pair; the data analysis module 12 is used for collecting the current data of the key position pair in the scene circuit, determining the overcurrent condition and generating the protection trigger instruction by performing time-frequency analysis, wherein the overcurrent condition includes an overcurrent type; the protection strategy determination module 13 is used for activating the intelligent decision maker embedded in the integrated circuit control according to the protection trigger instruction, performing parallel decision of the soft protection response and the rigid protection response for the overcurrent condition, and determining the overcurrent protection strategy; and the overcurrent protection management module 14 is used for performing overcurrent protection management on the access circuit according to the overcurrent protection strategy.

[0063] Further, the circuit equivalent module 11 in the automobile rectifier overcurrent protection system based on current feedback provided by the application is also used for: locating the steady-state access element and the fluctuation access element according to the working condition scene; performing differential equivalent processing based on the circuit topology of the steady-state access element and the fluctuation access element on the access circuit to determine the scene circuit; and storing the scene circuit into the integrated circuit control.

[0064] Further, the circuit equivalent module 11 in the automobile rectifier overcurrent protection system based on current feedback provided by the application is also used for: determining the first fluctuation part and the second fluctuation part for the fluctuation access element; performing processing on the access circuit by maintaining the circuit topology of the first fluctuation part, performing non-complete equivalent on the circuit topology of the second fluctuation part, and performing complete equivalent on the circuit topology of the steady-state access element to determine the scene circuit; and identifying the key position pair in the scene circuit for the working condition scene, wherein one key position pair includes a first remote end and a second near end, and the key position pair is a current feedback point.

[0065] Further, the data analysis module 12 in the automobile rectifier overcurrent protection system based on current feedback provided by the application is also used for: determining the first key position pair, wherein the first key position pair is any group of first remote end and second near end in the key position pair; determining the slope vector according to the current acceleration, performing dynamic out-of-limit judgment and mutual test on the first key position pair to determine the first judgment result; performing out-of-limit judgment and mutual test on the first key position pair based on the current threshold according to the current value to determine the second judgment result; and determining the overcurrent condition by performing overcurrent type judgment if at least one of the first judgment result and the second judgment result is met.

[0066] Further, the data analysis module 12 in the current application is further used for: taking the sudden surge of high-frequency component as the judgment feature to make the transient overcurrent judgment, and determining the first overcurrent type, wherein the first overcurrent type is the transient surge state; taking the continuous over-limit of low-frequency current as the judgment feature to make the steady-state overload judgment, and determining the second overcurrent type, wherein the second overcurrent type is the continuous short-circuit state; wherein if the second judgment result is met, the first overcurrent type or the second overcurrent type is determined in combination with the first judgment result.

[0067] Further, the data analysis module 12 in the current application is further used for: if the second judgment result is not met, the first judgment result is met, and the third pre-overcurrent type is determined according to the abnormality of the slope vector, wherein the third pre-overcurrent type is the pre-warning state.

[0068] Further, the protection strategy determination module 13 in the current application is further used for: deploying the first decision channel for the soft protection response, wherein the soft protection response is in the form of gradually reducing the duty cycle; deploying the second decision channel for the rigid protection response, wherein the rigid protection response is in the form of shutdown; and parallelizing the first decision channel and the second decision channel, and through the supervised training to convergence, as the intelligent decision maker.

[0069] Further, the protection strategy determination module 13 in the current application is further used for: according to the protection trigger instruction, activating the intelligent decision maker, executing the parallel decision based on the first decision channel and the second decision channel for the overcurrent condition, and determining the first strategy and the second strategy; if the first strategy is a non-empty set, taking the first strategy as the overcurrent protection strategy; if the first strategy is an empty set, taking the second strategy as the overcurrent protection strategy.

[0070] Further, the data analysis module 12 in the current application is further used for: making a priori on the overcurrent condition to determine whether it is the first inducement, wherein the first inducement refers to the element fault or the branch fault; if it is the first inducement, isolating the fault circuit topology through the shutdown control of the circuit breaker for the fault circuit topology.

[0071] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The foregoing Figure 1The current feedback based over-current protection method and specific examples in Embodiment One are also applicable to the current feedback based over-current protection system of this embodiment. Through the foregoing detailed description of the current feedback based over-current protection method, those skilled in the art can clearly understand the current feedback based over-current protection system of this embodiment. Therefore, for the sake of brevity of the description, no further detailed description is given here.

[0072] The above description of disclosed embodiments enables one skilled in the art to make or use the application. Numerous modifications to these embodiments will be apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Therefore, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0073] Obviously, for those skilled in the art, several improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the present application.

Claims

1. A current feedback based overcurrent protection method for automotive rectifiers, characterized in that, The method comprises: In the integrated circuit, the access circuit of the rectifier is obtained, the access circuit is equivalent according to the working condition scene of the rectifier, the scene circuit is determined and stored in the control area, wherein the differential equivalent mode is adopted, and the scene circuit identifies the key position pair; Current data of the key position pair in the scene circuit is collected, time-frequency analysis is performed, overcurrent conditions are determined, and protection trigger instructions are generated, wherein the overcurrent conditions include overcurrent types; According to the protection trigger instruction, the intelligent decision maker embedded in the integrated circuit control is activated, the parallel decision of soft protection response and rigid protection response is executed for the overcurrent conditions, and the overcurrent protection strategy is determined; According to the overcurrent protection strategy, the overcurrent protection management is performed on the access circuit; Wherein, according to the working condition scene of the rectifier, the access circuit is equivalent, including: According to the working condition scene, the steady-state access element and the fluctuation access element are located; For the access circuit, differential equivalent processing based on the circuit topology of the steady-state access element and the fluctuation access element is performed to determine the scene circuit; The scene circuit is stored in the integrated circuit control; The differential equivalent processing based on the circuit topology of the steady-state access element and the fluctuation access element includes: For the fluctuation access element, the first fluctuation part and the second fluctuation part are determined; The circuit topology of the first fluctuation part is maintained, the circuit topology of the second fluctuation part is not completely equivalent, and the circuit topology of the steady-state access element is completely equivalent, the access circuit is processed, and the scene circuit is determined; For the working condition scene, the key position pair is identified in the scene circuit, wherein a key position pair includes a first remote end and a second near end, and the key position pair is a current feedback point; Through time-frequency analysis, the overcurrent condition is determined, including: Determine the first key position pair, wherein the first key position pair is any group of first remote end and second near end in the key position pair; According to the current acceleration, the slope vector is determined, the dynamic out-of-limit judgment and mutual test of the first key position pair are performed, and the first judgment result is determined; According to the current value, the out-of-limit judgment and mutual test of the first key position pair based on the current threshold are performed, and the second judgment result is determined; If at least one of the first judgment result and the second judgment result is met, the overcurrent condition is determined by performing overcurrent type judgment; The overcurrent type judgment includes: The sudden surge of high frequency component is taken as the judgment characteristic to determine the first overcurrent type by performing instantaneous overcurrent judgment, wherein the first overcurrent type is instantaneous surge state; The sustained out-of-limit of low frequency current is taken as the judgment characteristic to determine the second overcurrent type by performing steady-state overload judgment, wherein the second overcurrent type is continuous short circuit state; If the second judgment result is met, the first overcurrent type or the second overcurrent type is determined in combination with the first judgment result.

2. The current feedback based overcurrent protection method for an automotive rectifier of claim 1, wherein, If the second judgment result is not met, the third premonitory overcurrent type is determined by the abnormality of the slope vector when the first judgment result is met, wherein the third premonitory overcurrent type is premonitory warning state.

3. The current feedback based overcurrent protection method for automotive rectifier of claim 1, wherein, Before activating the intelligent decision maker embedded in the integrated circuit controller, the construction of the intelligent decision maker includes: First decision channel deployment for soft protection response, wherein the soft protection response is in the form of step-down duty cycle; Second decision channel deployment for rigid protection response, wherein the rigid protection response is in the form of shutdown; Parallel the first decision channel and the second decision channel, and through supervised training to convergence, as the intelligent decision maker.

4. The current feedback based overcurrent protection method for an automotive rectifier of claim 3, wherein, Parallel decision of soft protection response and rigid protection response to determine the overcurrent protection strategy includes: According to the protection trigger instruction, activate the intelligent decision maker, and execute parallel decision of the first decision channel and the second decision channel for the overcurrent condition to determine the first strategy and the second strategy; If the first strategy is a non-empty set, the first strategy is taken as the overcurrent protection strategy; If the first strategy is an empty set, the second strategy is taken as the overcurrent protection strategy.

5. The current feedback based overcurrent protection method for automotive rectifier of claim 1, wherein, After determining the overcurrent condition, includes: Prior to the overcurrent condition, determine whether it is the first inducement, wherein the first inducement refers to element failure or branch failure; If it is the first inducement, isolate the fault circuit topology through the shutdown control of the circuit breaker for the fault circuit topology.

6. A current feedback based overcurrent protection system for an automotive rectifier characterized in that, Steps for implementing the overcurrent protection method of the automobile rectifier based on current feedback in any one of claims 1 to 5, including: A circuit equivalent module is used to isolate the storage area in the integrated circuit controller, obtain the access circuit of the rectifier, and determine the scene circuit and store it in the built-in storage area by equivalent to the access circuit according to the working condition scene of the rectifier, wherein the differential equivalent mode is adopted, and the scene circuit is marked with key position pairs; A data analysis module is used to collect current data of key position pairs in the scene circuit, determine the overcurrent condition and generate a protection trigger instruction by time-frequency analysis, wherein the overcurrent condition includes overcurrent type; A protection strategy determination module is used to activate the intelligent decision maker embedded in the integrated circuit controller according to the protection trigger instruction, execute parallel decision of soft protection response and rigid protection response for the overcurrent condition, and determine the overcurrent protection strategy; An overcurrent protection management module is used to manage the overcurrent protection of the access circuit according to the overcurrent protection strategy.

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