Electric energy router fault current isolation method based on insulated gate bipolar transistor

Abstract

The invention discloses an electric energy router fault current isolation method based on an insulated gate bipolar transistor, and relates to the field related to the technical field of power electronics, and the method comprises the steps: building a circuit fault control mechanism based on the connection relation between an electric energy router and the insulated gate bipolar transistor and the environment; a sensor is installed in the electric energy router to monitor and obtain data, the data are preprocessed and then input into a fault discriminator to obtain information, the information is matched with a current isolation mechanism in a control mechanism, and when the information is matched with the current isolation mechanism, turn-off isolation control of an insulated gate bipolar transistor is activated to enable the grid voltage to be reduced to zero. The technical problem of insufficient operation reliability and accuracy caused by insufficient fault current isolation accuracy and imperfect control mechanism of the existing electric energy router is solved, and the technical effects of improving the fault current isolation accuracy and ensuring the stable operation of the electric energy router are achieved.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to a fault current isolation method for an energy router based on an insulated gate bipolar transistor. Background Art

[0002] In the power conversion system, the demand for large current capacity is becoming more and more urgent, but the current carrying capacity of a single insulated gate bipolar transistor (IGBT) device is close to the limit due to the limitations of material properties and manufacturing processes, and it is difficult to meet the demand. Although the direct parallel application of multiple IGBTs can improve the transmission capacity of the power conversion system, when operating in parallel, factors such as the symmetry of the power circuit structure, the consistency of the drive signal, the characteristic parameters of each parallel IGBT and the change of junction temperature will cause the static and dynamic uneven current of the IGBT, affecting the normal operation of the system. There are many shortcomings in the traditional processing method, such as poor suppression of parallel uneven current phenomenon, inability to ensure the balance of static and dynamic currents of each parallel branch IGBT, inability to meet the current capacity requirements of the parallel system, and difficulty in ensuring the reliability, safety and stability of the operation of the power router.

[0003] Among the current related technologies, power routers have technical problems such as insufficient fault current isolation accuracy and imperfect control mechanism, resulting in insufficient operational reliability and accuracy. Summary of the invention

[0004] The present application provides a method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor, and adopts a circuit fault control mechanism based on the connection relationship and environment between the electric energy router and the insulated gate bipolar transistor. A sensor is installed in the electric energy router to monitor and obtain data, and the information is input into the fault discriminator after preprocessing, and the information is matched with the current isolation mechanism in the control mechanism. When the information meets the requirements, the turn-off isolation control of the insulated gate bipolar transistor is activated to reduce the gate voltage to zero, thereby improving the accuracy of fault current isolation and ensuring the technical effect of stable operation of the electric energy router.

[0005] The present application provides a method for isolating a fault current of an electric energy router based on an insulated gate bipolar transistor, comprising:

[0006] Based on the circuit connection relationship and circuit connection environment of the power router and the insulated gate bipolar transistor, a circuit fault control mechanism is constructed; a current sensor and a voltage sensor are installed in the power router to monitor and obtain circuit monitoring data in real time; the circuit monitoring data is input into a fault discriminator after data preprocessing to obtain fault discrimination information; the fault discrimination information is matched with the current isolation mechanism in the circuit fault control mechanism; when the matching result conforms to the current isolation mechanism, the turn-off isolation control of the insulated gate bipolar transistor is activated, and the gate voltage is driven to drop to zero based on the turn-off isolation control.

[0007] The method for isolating the fault current of the power router based on the insulated gate bipolar transistor proposed in this application first constructs a circuit fault control mechanism based on the connection relationship and environment between the power router and the insulated gate bipolar transistor. Sensors are installed in the power router to monitor and obtain data, which are input into the fault discriminator after preprocessing to obtain information, and this information is matched with the current isolation mechanism in the control mechanism. When it meets the requirements, the turn-off isolation control of the insulated gate bipolar transistor is activated to reduce the gate voltage to zero, thereby achieving the technical effect of improving the accuracy of fault current isolation and ensuring the stable operation of the power router. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the accompanying drawings of the embodiment of the present invention will be briefly introduced below. A flow chart is used in the present application to illustrate the operations performed by the system according to the embodiment of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps can be processed in reverse order or simultaneously as needed. At the same time, other operations can also be added to these processes, or one or more operations can be removed from these processes.

[0009] Figure 1 A schematic flow chart of a fault current isolation method for an electric energy router based on an insulated gate bipolar transistor provided in an embodiment of the present application;

[0010] Figure 2 A schematic diagram of a process for obtaining a fault discriminator provided in an embodiment of the present application. DETAILED DESCRIPTION

[0011] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below.

[0012] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of this application.

[0013] In the following description, reference is made to "some embodiments", which describe a subset of all possible embodiments, but it is understood that "some embodiments" may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict, and the terms "first\second" involved are merely to distinguish similar objects and do not represent a specific ordering of objects. The terms "including" and "having" and any variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or server that includes a series of steps S or units is not necessarily limited to those steps S or units that are clearly listed, but may include other steps S or modules that are not clearly listed or inherent to these processes, methods, products, or devices. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by technicians in the technical field of this application. The terms used herein are for the purpose of describing the embodiments of the present application only.

[0014] The present application embodiment provides a method for isolating a fault current of an energy router based on an insulated gate bipolar transistor, such as Figure 1 As shown, the method includes:

[0015] Step S100, based on the circuit connection relationship and circuit connection environment of the power router and the insulated gate bipolar transistor, a circuit fault control mechanism is constructed. Specifically, the circuit connection relationship between the power router and the insulated gate bipolar transistor (IGBT) is studied, including the connection mode and the current and voltage transmission path, the circuit connection environment is evaluated, such as temperature, humidity, electromagnetic interference, etc., and the possible fault types and causes are analyzed, such as overcurrent, short circuit, overheating, etc., and control strategies are formulated accordingly, such as setting thresholds, adjusting duty cycles, installing protection devices, etc., real-time monitoring of circuit operation status, comparison of key parameters with preset values, and optimization and improvement through simulation tests and actual verification.

[0016] In a possible implementation, a circuit fault control mechanism is constructed based on the circuit connection relationship and circuit connection environment of the power router and the insulated gate bipolar transistor, and step S100 further includes step S110, extracting entities to establish a circuit connection diagram based on the circuit connection relationship of the power router and the insulated gate bipolar transistor. Specifically, according to the circuit connection relationship between the power router and the insulated gate bipolar transistor, the key elements and connection methods therein are carefully studied and sorted out, and representative and key entities such as resistors, capacitors, inductors, transistors and other components, as well as the lines and nodes connecting these components, are extracted from the complex circuit structure. Based on the extracted entities, a clear and accurate circuit connection diagram is constructed to intuitively display the electrical connection relationship between the various components in the circuit, providing a basis for subsequent analysis and calculation.

[0017] Step S120, collect the output connection equipment of the power router, calculate the fault current loss value of the output connection equipment, and fit it into the circuit connection diagram as the circuit connection environment. Specifically, collect the relevant data of the output connection equipment of the power router, including the normal working current, rated power, current and voltage values ​​of the fault, fault duration and other information of the equipment, and use the data to calculate the formula: The loss value of the output connection device under the fault current condition is accurately calculated, and the calculated fault current loss value is used as an important parameter of the circuit connection environment and fitted into the previously established circuit connection diagram to more comprehensively reflect the actual operation status of the circuit.

[0018] Step S130, based on the circuit connection diagram, analyze the current path and voltage distribution of the circuit, and determine the device nodes. Specifically, based on the constructed circuit connection diagram that includes the circuit connection environment parameters, deeply analyze the current path in the circuit, determine the flow direction and possible branching of the current from the power supply through each component and node, analyze the distribution of voltage in the circuit, clarify the voltage difference of each part, and accurately determine the key device nodes in the circuit through a comprehensive analysis of the current path and voltage distribution. The nodes are usually locations where the current and voltage changes are more significant and have an important impact on the circuit performance and stability.

[0019] Step S140, analyze the current isolation strategy of the device node according to the current path and voltage distribution, and construct the circuit fault control mechanism, which is used to characterize the control target requirements for different device nodes of fault current. Specifically, according to the clear current path and voltage distribution, analyze the current isolation strategy for the determined device nodes, consider the tolerance and working requirements of the device nodes under different fault current conditions, and formulate corresponding control strategies, such as disconnecting, limiting current or reducing voltage for certain nodes under specific fault currents. Through detailed analysis and strategy formulation of each device node, a complete circuit fault control mechanism is constructed, which clearly stipulates the control targets and requirements that each device node should achieve under different fault current scenarios, so as to ensure that measures can be taken quickly and effectively when a fault occurs to protect the safe and stable operation of circuits and equipment.

[0020] In a possible implementation, the current isolation strategy of the device node is analyzed according to the current path and voltage distribution, and the circuit fault control mechanism is constructed. The circuit fault control mechanism is used to characterize the control target requirements of different device nodes for fault currents. Step S140 further includes step S141, collecting circuit parameters, historical monitoring data, status data, and current impact data of the device node, and constructing a simulation space based on the circuit connection diagram, current path, and voltage distribution. Specifically, all data of the device node are collected comprehensively, and the circuit parameters include the values ​​of components such as resistors, capacitors, and inductors; the historical monitoring data covers the changes in the current, voltage, etc. of the device node over a period of time in the past; the status data includes the working status of the device node, whether there is a fault record, etc.; the current impact data involves the specific impact of the current change on the device node. Based on the collected data, combined with the constructed circuit connection diagram, clear current path, and voltage distribution, a highly simulated simulation space is created, which can realistically simulate the actual operation of the circuit.

[0021] Step S142, the simulation space includes a pre-parameter adjustment module and a post-state identification module, and the fault current of the power router and the control strategy of the insulated gate bipolar transistor are simulated and adjusted through the parameter adjustment module, and the current characteristic simulation experiment is performed using the simulation space, and the state identification module is used to identify and output the device state of the device node according to the state data and current influence data to obtain the simulation experiment data. Specifically, in this simulation space, there are a pre-parameter adjustment module and a post-state identification module. The pre-parameter adjustment module has powerful functions and can flexibly simulate and adjust the fault current of the power router and the control strategy of the insulated gate bipolar transistor. For example, the magnitude, frequency, and duration of the fault current are changed, or the control parameters such as the on and off time and gate voltage of the insulated gate bipolar transistor are adjusted to simulate various possible fault conditions and changes in the control strategy, and the current characteristic simulation experiment is carried out using this simulation space. During the experiment, by continuously adjusting parameters, fault currents of different degrees and types are simulated to observe their impact on device nodes. The post-state recognition module accurately identifies and outputs the device status of device nodes under different simulation conditions based on the collected status data and current impact data. For example, it determines whether the device node is in normal working state, overload state or fault state, etc., and organizes these recognition results into detailed data. Through simulation experiments, rich simulation experiment data is obtained. The data reflects the performance and state changes of device nodes under various parameter settings and fault conditions.

[0022] Step S143, fitting the safety control strategy of each device node according to the simulation experiment data, and constructing the circuit fault control mechanism, which is used to characterize the current isolation strategy of each device node to ensure the normal operation of its equipment under different fault currents. Specifically, according to the obtained simulation experiment data, the safety control strategy of each device node is fitted, and it is analyzed which control strategies can effectively ensure the normal operation of the device node under different fault currents, and which need further optimization or adjustment. Through fitting and analysis, a circuit fault control mechanism that can ensure the normal operation of each device node under different fault current conditions is constructed. The mechanism clarifies the specific current isolation strategy that each device node should adopt for various fault conditions, and provides a reliable basis and guidance for fault handling of actual circuits.

[0023] In a possible implementation, the simulation space includes a pre-parameter adjustment module and a post-state identification module. The parameter adjustment module is used to simulate and adjust the fault current and insulated gate bipolar transistor control strategy of the power router. The simulation space is used to perform a current characteristic simulation experiment. The state identification module is used to output the device state of the device node according to the state data and current influence data to obtain simulation experiment data. Step S142 further includes step S1421, setting the fault current adjustment threshold and adjustment step according to the fault current signal characteristics. Specifically, the acquired fault current signal characteristics are analyzed, and the characteristics include information such as the current amplitude, frequency, change trend, duration, etc. Based on a comprehensive understanding of the characteristics, in order to effectively control and adjust the fault current, the corresponding fault current adjustment threshold and a reasonable adjustment step are set. The setting of the adjustment threshold determines when the fault current is considered to have reached a level that requires intervention and adjustment, and comprehensively considers multiple factors such as the normal working range of the circuit, the tolerance of the equipment, and the safety requirements of the system. For example, if the normal current fluctuation range in the circuit is small, and the equipment has limited tolerance to overcurrent, then the threshold needs to be set relatively low to ensure that timely measures can be taken when the fault current just exceeds the safety range. The determination of the adjustment step affects the accuracy and speed of fault current control. A smaller step can achieve more precise adjustment, but it will result in a slower adjustment process. A larger step can quickly change the fault current and cause larger current fluctuations. A balance is found between the accuracy and speed of adjustment, and the appropriate step is determined according to the specific circuit characteristics and control requirements.

[0024] Step S1422, the insulated gate bipolar transistor control strategy is optimized by the optimization module to determine the fault control strategy. Specifically, the control strategy of the insulated gate bipolar transistor is optimized by the optimization module, and the optimization process involves genetic algorithms, particle swarm optimization algorithms, etc. The optimization module will search and evaluate in a given control strategy space to find the optimal fault control strategy. In the optimization process, multiple factors are comprehensively considered, such as the control strategy's suppression effect on fault current, the impact on other parts of the circuit, the complexity and cost of control, etc., and the optimization module can gradually screen out the control strategy that best suits the current circuit and fault condition through continuous iteration and calculation.

[0025] Step S1423, using the fault current adjustment threshold and adjustment step, and the fault control strategy to simulate the adjustment of the parameter adjustment module. Specifically, using the previously set fault current adjustment threshold, adjustment step, and determined fault control strategy, the parameter adjustment module is simulated and adjusted. The parameter adjustment module changes the relevant parameters of the insulated gate bipolar transistor accordingly according to the setting of the threshold and step, and the requirements of the fault control strategy. For example, if the fault current exceeds the set threshold, the parameter adjustment module will adjust the parameters such as the on-time, off-time, and gate voltage of the insulated gate bipolar transistor according to the determined step and control strategy, so as to achieve effective control and adjustment of the fault current, so that it can be restored to a safe range as soon as possible, and ensure the normal operation of the circuit.

[0026] In a possible implementation, the output connection device of the power router is collected, and the fault current loss value of the output connection device is calculated as the circuit connection environment, which is fitted into the circuit connection diagram. Step S120 further includes step S121, through the formula: Calculate the fault current loss value of the output connection device, where I fault is the fault current, I normal is the normal working current, ∝, β is the weight coefficient, V fault is the fault voltage corresponding to the fault current, t fault is the duration of the fault current, p rated Specifically, it is necessary to obtain the key parameters of the output connection device when a fault occurs, including accurate measurement of the fault current (I fault ) value, which can usually be obtained through a special current sensor or measuring instrument to record the current (I normal), which is usually available in the equipment specification or in previous normal operation monitoring data. The weight coefficient (∝, β) is usually set based on experience, experimental data, or in-depth research on equipment characteristics and fault impacts. It plays a role in adjusting the weights of different parts contributing to the loss value in the calculation. The fault voltage (V fault ), use appropriate voltage measurement tools to obtain this data, and record the duration of the fault current (t fault ), it is necessary to accurately monitor and record the start and end time of the fault and obtain the rated power (p rated ), this value is usually clearly marked on the nameplate or technical specification document of the equipment. Calculate it according to the calculation rules of the formula, first calculate the numerator and square it, and then calculate and The values ​​of these two parts are obtained by adding the above two calculation results, and the sum is the fault current loss value (L) of the output connected device, so as to ensure that the fault current loss value finally calculated can truly reflect the degree of loss suffered by the equipment in the event of a fault, and provide an important basis for subsequent fault analysis, control strategy formulation, and equipment maintenance and replacement decisions.

[0027] Step S200, install current sensors and voltage sensors in the power router to monitor and obtain circuit monitoring data in real time. Specifically, select current sensors and voltage sensors that are suitable for the working characteristics and monitoring requirements of the power router. The selection of sensors needs to consider multiple factors such as measurement range, accuracy, response speed, stability, etc. For example, if the current processed by the power router is large, it is necessary to select a current sensor that can measure large currents and has sufficiently high accuracy; for voltage sensors, it is necessary to ensure that they can accurately measure the voltage range involved in the power router. After determining the sensor model, start the installation work. The selection of the installation location is crucial. It is necessary to consider the current and voltage conditions of the key parts of the circuit that can be accurately reflected. Sensors will be installed at the input and output ports of the power router, important branch lines, and nodes connected to other key devices. During the installation process, it is necessary to ensure that the connection between the sensor and the circuit is firm and reliable, and the contact is good to avoid signal interference and measurement errors. It involves the use of appropriate connection terminals and wires, and follows strict electrical installation specifications and safety standards. After the installation is completed, the sensor is initialized and calibrated. The calibration process usually uses known The output of the sensor is adjusted by using a standard current and voltage source to ensure the accuracy of its measured value. After the sensor is installed and calibrated, it is connected to the data acquisition system. The data acquisition system can be a dedicated hardware device or a software module embedded in the power router control system. During the operation of the power router, the current sensor and the voltage sensor will sense the current and voltage changes in the circuit in real time and convert these changes into electrical signal outputs. The data acquisition system samples and digitizes these electrical signals at an extremely high frequency and converts them into circuit monitoring data for subsequent analysis and processing. In order to ensure the real-time and continuity of the data, the data acquisition system usually has high-speed data processing capabilities and sufficient storage capacity. It can process a large amount of data in a short time and store it for subsequent analysis. A data transmission channel is established to transmit the real-time circuit monitoring data to the monitoring center or remote server so that relevant personnel can understand the working status of the power router in a timely manner and take quick measures when abnormal situations occur.

[0028] Step S300, the circuit monitoring data is preprocessed and then input into the fault discriminator to obtain fault discrimination information. Specifically, the circuit monitoring data from the power router is obtained. The data is usually the original, unprocessed current and voltage numerical sequence. Next, data preprocessing is performed. This link includes multiple steps, such as cleaning the data to remove possible outliers and noise. Outliers may be data points that are obviously deviated from the normal range due to sensor failure, transmission error or other sudden interference. Noise may be small random fluctuations introduced by factors such as electromagnetic interference in the measurement environment. The cleaned data is standardized or normalized. Standardization can make data of different magnitudes and units comparable. Normalization maps the data to a specific range, such as the [0,1] interval, for subsequent calculation and analysis. After preprocessing, the processed data is input into the fault discriminator. Fault discriminators are usually built based on specific algorithms and models. The algorithms and models are based on rule and threshold discrimination methods. The data will be compared with pre-set thresholds and rules. For example, if the current or voltage exceeds a certain set upper or lower limit, it will be judged as a fault. After processing and analysis by the fault discriminator, the fault discrimination information is finally output. The information is a related description of the fault type, fault severity, location of the fault, etc.

[0029] In a possible implementation, the circuit monitoring data is pre-processed and then input into a fault discriminator, such as Figure 2 As shown, step S300 further includes step S310, collecting the fault current of the power router and constructing a fault current sample set. Specifically, the fault current generated by the power router in different operating states and fault conditions is collected by monitoring means, and the collected fault current data constitutes a fault current sample set. Assume that within a period of time, a total of 1000 fault current data points are collected, thereby constructing a fault current sample set.

[0030] Step S320, divide the samples of the fault current categories in the fault current sample set, evaluate the sample balance of the divided categories, and supplement the samples of the categories that do not meet the sample balance, so as to meet the balance requirements of the samples of each category. Specifically, the fault current categories in the fault current sample set are divided into detailed samples, and classified based on factors such as the amplitude, duration, and change characteristics of the fault current. The sample balance of each divided category is evaluated. Sample balance refers to whether the distribution of the number of samples in different categories is uniform. If the number of samples in some categories is too large and the number of samples in some categories is too small, it will lead to sample imbalance. For categories that do not meet the sample balance requirements, samples are supplemented in various ways. For example, existing samples can be expanded by data enhancement techniques such as flipping, rotating, scaling, etc., or from other categories. Supplementary samples are obtained from similar data sources to ensure that the number of samples in each category is relatively balanced. Suppose they are divided into three categories: A, B, and C. After preliminary statistics, there are 300 samples in Category A, 200 samples in Category B, and 500 samples in Category C. The sample balance of the divided categories is evaluated and it is found that the number of samples in Category A and Category B is relatively small, which does not meet the sample balance requirements. In order to meet the balance, samples in Category A and Category B are supplemented. Assuming that the principle of supplementation is to make the ratio of its number to Category C reach 1:1.5, then it is necessary to supplement Category A samples to 375 and Category B samples to 375.

[0031] Step S330, configure the training set, test set, and validation set according to the ratio of the number of data sets. Specifically, after completing the sample division and balance processing, configure the training set, test set, and validation set according to the preset ratio of the number of data sets. Usually, the training set accounts for a larger proportion and is used for the main learning process of the discriminator; the test set is used to make a preliminary evaluation of the performance of the discriminator during the training process; the validation set is used to finally adjust and determine the performance of the discriminator. Assuming that the division is carried out in a ratio of 7:2:1, the training set will contain 700 samples, the test set will contain 200 samples, and the validation set will contain 100 samples.

[0032] Step S340, using the support vector machine as a discriminator, using the training set, test set, and validation set to train and validate the discriminator, and adjusting hyperparameters. Specifically, a support vector machine is selected as the discriminator, and the discriminator is trained using the configured training set to allow the discriminator to learn the characteristics and patterns of different types of fault currents. During the training process, the test set is used to perform periodic performance evaluation on the discriminator, and the parameters of the discriminator are adjusted according to the evaluation results.

[0033] Step S350, cross-validate the discriminator using the validation set until the evaluation and validation index is met, and determine the hyperparameters to obtain the fault discriminator. Specifically, the validation set is used to cross-validate the discriminator. Cross-validation is a method for evaluating model performance. The validation set data is divided into multiple subsets, one of which is used as validation data and the remaining subsets are used as training data in turn. Training and validation are repeated multiple times to comprehensively evaluate the performance of the discriminator, and the hyperparameters of the discriminator, such as the kernel function type and the penalty coefficient, are continuously adjusted until the performance of the discriminator on the validation set meets the pre-set evaluation and validation index. Once the performance of the discriminator on the validation set meets the requirements, the hyperparameters at this time are determined, thereby obtaining a fault discriminator that can accurately discriminate the fault current category of the power router. Assuming that the evaluation and validation index is an accuracy rate of more than 90%, if the accuracy rate of the first cross-validation is 85%, which does not meet the requirements, the hyperparameters are continuously adjusted to train and validate again until the accuracy rate reaches 90% or more, thereby determining the final hyperparameters and obtaining a fault discriminator that can accurately discriminate faults.

[0034] Step S400, matching the fault discrimination information with the current isolation mechanism in the circuit fault control mechanism. Specifically, it is necessary to obtain fault discrimination information. From various fault detection means or systems, such as sensor monitoring, circuit analysis, etc., the information can indicate the possible fault type or abnormal situation in the circuit. The current isolation mechanism has been set in the circuit fault control mechanism. The current isolation mechanism is to take appropriate measures to isolate the faulty part when a circuit fails, so as to protect other normal parts of the circuit from being affected and ensure the stable operation of the entire system. To match the fault discrimination information with the current isolation mechanism, it is necessary to understand in detail the specific fault characteristics represented by the fault discrimination information and the corresponding isolation strategies set for different fault conditions in the current isolation mechanism. Specifically, it is necessary to compare the key parameters or signs in the fault discrimination information and match them with the various fault conditions defined in the current isolation mechanism. For example, if the fault discrimination information indicates a certain type of fault, such as a short circuit fault or an overcurrent fault, then it is necessary to find the isolation operation specified for this type of fault in the current isolation mechanism. In the matching process, multiple factors may need to be considered. On the one hand, it is necessary to ensure the accuracy and completeness of the fault discrimination information so that it can be accurately Corresponding to the corresponding isolation mechanism, on the other hand, the current isolation mechanism itself may have certain complexity and diversity, and its applicable conditions and execution methods need to be carefully analyzed. Once a matching current isolation strategy is found, the specific control actions to be taken for the current fault can be determined. The control actions include cutting off specific circuit parts, adjusting circuit parameters, starting backup circuits, etc., to achieve effective isolation of the current, prevent the fault from expanding, and minimize the impact on the normal operation of the system. In order to ensure the accuracy and effectiveness of the matching, real-time monitoring and feedback may also be required. After executing the current isolation control, continue to observe the operating status of the circuit to verify whether the isolation strategy has achieved the expected effect. If it is found that the isolation effect is not ideal or new problems arise, it is necessary to re-identify and match the fault, or adjust and optimize the current isolation mechanism. The key lies in accurately understanding the fault identification information and the current isolation mechanism, finding a suitable isolation strategy through effective matching, and timely execution and monitoring to ensure the safe and stable operation of the circuit, and continuously improving and optimizing the fault identification and isolation mechanism according to the actual operation conditions to improve the system's ability to cope with various faults.

[0035] Step S500, when the matching result conforms to the current isolation mechanism, activate the turn-off isolation control of the insulated gate bipolar transistor, and drive the gate voltage to zero based on the turn-off isolation control. Specifically, when the matching of the fault discrimination information and the current isolation mechanism is completed, and the matching result shows that it conforms to the preset current isolation mechanism, the system will immediately initiate a series of response actions. First, the turn-off isolation control function of the insulated gate bipolar transistor (IGBT) is activated, and the activation signal will be transmitted to the control circuit related to the IGBT, triggering the special control logic and circuit to start working. After the turn-off isolation control is activated, the control circuit will respond quickly and take measures to reduce the gate voltage of the IGBT to zero, which is achieved by adjusting the circuit elements connected to the gate. Specifically, the control circuit may change the value of the gate resistance, or adjust the charge and discharge state of the gate capacitance to achieve a rapid and smooth reduction in the gate voltage. It is necessary to accurately control the changes in current and voltage to achieve this. Avoid excessive voltage spikes or current shocks, thereby protecting the safety of the IGBT and the entire circuit system. As the gate voltage gradually drops to zero, the IGBT will change from the on state to the off state, thereby cutting off the current path in the circuit and isolating the faulty part from the normal part. During the entire process, the system will continuously monitor the changes in the gate voltage to ensure that it drops to zero at a predetermined speed and amplitude, monitor other key parameters in the circuit, such as current, voltage, etc., to verify the effectiveness of the isolation control, and take corresponding protection measures when abnormal conditions occur. When the matching result meets the current isolation mechanism, it can effectively activate the IGBT's shutdown isolation control, reduce the gate voltage to zero, and achieve rapid and accurate isolation of circuit faults, thereby ensuring the stable operation and safety of the entire system.

[0036] In a possible implementation, after step S300, the method further includes: step S360 of matching the fault identification information with the circuit fault control mechanism, and when the matching result is an overcurrent protection mechanism, obtaining the overcurrent amount and calculating the adjusted duty cycle. Specifically, fault identification information is obtained, and a description of the circuit fault type and characteristics is obtained after analyzing and processing the circuit monitoring data. This fault identification information is matched with a pre-set circuit fault control mechanism. The circuit fault control mechanism includes a variety of response strategies and processing methods for different fault conditions. When the matching result shows that the overcurrent protection mechanism is triggered, the duty cycle is calculated and adjusted. The duty cycle is simply the proportion of the insulated gate bipolar transistor on-time in the entire cycle time. To adjust the duty cycle, it is assumed that the current we expect is a specific value, and there is an equivalent resistor in the circuit that is equivalent to resistance. If the overcurrent is too large, in order to adjust the current to the expected value, the duty cycle must be changed accordingly. For example, the original duty cycle can keep the current in a normal state. Now there is an overcurrent, and the duty cycle must be re-determined based on the comparison between the expected current and the overcurrent. If the expected current is small and the overcurrent is large, then the new duty cycle must be reduced, that is, the proportion of the insulated gate bipolar transistor on-time in the entire cycle is reduced.

[0037] Step S370, according to the adjusted duty cycle, a pulse width modulation signal is generated to control the conduction time of the insulated gate bipolar transistor and filter out the high-frequency components of the current. Specifically, according to the calculated adjusted duty cycle, a corresponding pulse width modulation (PWM) signal is generated. A PWM signal is a periodic digital signal, and the duration ratio of its high level and low level is determined by the duty cycle. The generated PWM signal is used to control the conduction time of an insulated gate bipolar transistor (IGBT). When the PWM signal is at a high level, the IGBT is turned on; when it is at a low level, the IGBT is turned off. By adjusting the conduction time, effective control of the current in the circuit is achieved, and the high-frequency components in the current are filtered out by a filter circuit. The filter circuit can be composed of components such as inductors and capacitors. Its function is to smooth the current waveform, reduce high-frequency noise and interference in the current, make the current more stable and pure, and effectively deal with overcurrent faults to ensure the safe and stable operation of the circuit. Among them, the larger the duty cycle, the longer the conduction time; the smaller the duty cycle, the shorter the conduction time. By controlling the conduction time, the current can be adjusted.

[0038] In a possible implementation, step SA1, establishes a response relationship between the gate resistance value and the switching speed of the insulated gate bipolar transistor. Specifically, through theoretical analysis and experimental research, a response relationship between the gate resistance value and the switching speed of the insulated gate bipolar transistor is established, involving detailed measurement and analysis of the transistor switching process under different gate resistance values ​​to determine how the change in resistance value affects the speed of the switching. Assuming that the gate resistance value is changed, the corresponding switching speed is measured, for example, when the gate resistance is 10 ohms, the switching speed is 10μs; when the gate resistance is 20 ohms, the switching speed is 20μs, and a roughly linear or nonlinear response relationship is established.

[0039] Step SA2, obtain the switch monitoring data set of the insulated gate bipolar transistor, and fit the driving control relationship between the driving voltage amplitude, the change rate and the switching speed. Specifically, a large number of switching monitoring data sets of the insulated gate bipolar transistor are obtained, and the data includes information such as the amplitude, the change rate and the corresponding switching speed of the driving voltage during the switching process under different working conditions. Use data analysis and fitting technology to find the intrinsic driving control relationship between the driving voltage amplitude, the change rate and the switching speed. Assume that 50 sets of data are collected, including the driving voltage amplitude and the change rate and the corresponding switching speed. Through data fitting, such as using the least squares method, the driving control relationship between the driving voltage amplitude, the change rate and the switching speed is obtained. For example, when the driving voltage amplitude is 10V and the change rate is 2V / μs, the switching speed is 15μs.

[0040] Step SA3, based on the response relationship and the drive control relationship, a control list is constructed, which includes the control association relationship between the switching speed and the gate resistance value, the drive voltage amplitude, and the change rate. Specifically, based on the determined response relationship between the gate resistance value and the switching speed and the drive control relationship between the drive voltage and the switching speed, a detailed control list is constructed. The control list clearly presents the specific control association relationship between the switching speed and the gate resistance value, the drive voltage amplitude, and the change rate, which provides a basis for the subsequent control strategy formulation. Assuming that the switching speed has 5 levels, increasing from 1 to 5, for each level, the corresponding gate resistance value, drive voltage amplitude, and change rate are clearly defined. For example, the gate resistance value corresponding to the switching speed level 1 is 5 ohms, the drive voltage amplitude is 5V, and the change rate is 1V / μs.

[0041] Step SA4, based on the switching speed, the switching speed level is graded and mapped with the current isolation strategy. Specifically, the switching speed is graded according to actual needs and circuit characteristics. For example, the switching speed can be divided into different levels such as fast, medium, and slow. The corresponding current isolation strategy is mapped and associated for each switching speed level. The current isolation strategy is formulated according to the influence of different switching speeds on the circuit fault isolation effect and system stability. It is assumed that the switching speed is divided into three levels: low, medium, and high. The low level corresponds to a speed less than 10μs, the medium level corresponds to a speed between 10-20μs, and the high level corresponds to a speed greater than 20μs. The corresponding current isolation strategy is mapped and associated for each level. For example, the low level uses simple capacitor isolation, the medium level uses inductor capacitor combination isolation, and the high level uses complex magnetic isolation.

[0042] Step SA5, using the matching current isolation strategy of the fault discrimination information to match the associated switch speed level, and obtain the control parameters of the switch speed. Specifically, when fault discrimination information is generated, the current isolation strategy corresponding to the fault discrimination information is matched with the associated switch speed level that has been constructed. Through matching, the switch speed level suitable for the current fault situation can be determined, and the corresponding control parameters, such as gate resistance value, driving voltage amplitude and change rate, etc., can be obtained from the control list. The switching speed of the insulated gate bipolar transistor is accurately controlled by using the obtained control parameters to achieve effective current isolation and ensure the safe and stable operation of the power router. Assuming that the fault discrimination information indicates that a medium-level current isolation strategy is required, the corresponding switch speed control parameters, i.e., gate resistance value, driving voltage amplitude and change rate, etc., can be obtained from the control list to achieve accurate control of the switching speed of the insulated gate bipolar transistor.

[0043] The embodiment of the present application adopts a circuit fault control mechanism based on the connection relationship and environment between the power router and the insulated gate bipolar transistor. Sensors are installed in the power router to monitor and obtain data, and the information is input into the fault discriminator after pre-processing, and the information is matched with the current isolation mechanism in the control mechanism. When it meets the requirements, the turn-off isolation control of the insulated gate bipolar transistor is activated to make the gate voltage drop to zero, thereby achieving the technical effect of improving the accuracy of fault current isolation and ensuring the stable operation of the power router.

[0044] The above specific implementation manner does not constitute a limitation to the protection scope of the present application. It should be understood by those skilled in the art that various modifications, combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application. In some cases, the actions or steps S recorded in the present application can be performed in an order different from that in the embodiment and still achieve the desired results. In addition, the process depicted in the accompanying drawings does not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

Claims

1. A method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor, characterized in that: The electric energy router fault current isolation method based on insulated gate bipolar transistors includes: Based on the circuit connection relationship between the power router and the insulated gate bipolar transistor and the circuit connection environment, a circuit fault control mechanism is constructed; Installing a current sensor and a voltage sensor in the power router to monitor and obtain circuit monitoring data in real time; The circuit monitoring data is pre-processed and then input into a fault discriminator to obtain fault discrimination information; Matching the fault identification information with the current isolation mechanism in the circuit fault control mechanism; When the matching result meets the current isolation mechanism, the turn-off isolation control of the insulated gate bipolar transistor is activated, and the gate voltage is driven to drop to zero based on the turn-off isolation control.

2. The method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor according to claim 1, characterized in that: The circuit fault control mechanism is constructed based on the circuit connection relationship between the power router and the insulated gate bipolar transistor and the circuit connection environment, including: According to the circuit connection relationship between the power router and the insulated gate bipolar transistor, extract entities to establish a circuit connection diagram; Collecting the output connection devices of the power router, calculating the fault current loss value of the output connection devices as the circuit connection environment, and fitting it into the circuit connection diagram; Analyzing the current path and voltage distribution of the circuit based on the circuit connection diagram, and determining the device nodes; The current isolation strategy of the device node is analyzed according to the current path and voltage distribution, and the circuit fault control mechanism is constructed. The circuit fault control mechanism is used to characterize the control target requirements for different device nodes with fault currents.

3. The method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor according to claim 2, characterized in that: Performing a current isolation strategy analysis on the device node according to the current path and voltage distribution includes: Collecting circuit parameters, historical monitoring data, status data, and current impact data of the device nodes, and constructing a simulation space based on the circuit connection diagram, current path, and voltage distribution; The simulation space includes a pre-parameter adjustment module and a post-state identification module. The parameter adjustment module is used to simulate and adjust the fault current and the insulated gate bipolar transistor control strategy of the power router. The simulation space is used to perform a current characteristic simulation experiment. The state identification module is used to identify and output the device state of the device node according to the state data and current influence data to obtain simulation experiment data. The safety control strategy of each device node is fitted according to the simulation experiment data, and the circuit fault control mechanism is constructed. The circuit fault control mechanism is used to characterize the current isolation strategy of each device node to ensure the normal operation of its equipment under different fault currents.

4. The method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor according to claim 3, characterized in that: The parameter adjustment module is used to simulate the fault current and the insulated gate bipolar transistor control strategy of the power router, including: According to the fault current signal characteristics, setting the fault current adjustment threshold and adjustment step size; Optimizing the insulated gate bipolar transistor control strategy through an optimization module to determine a fault control strategy; The parameter adjustment module is simulated and adjusted using the fault current adjustment threshold, adjustment step, and fault control strategy.

5. The method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor according to claim 1, characterized in that: The obtaining of fault identification information further includes: The fault identification information is used to match the circuit fault control mechanism, and when the matching result is an overcurrent protection mechanism, the overcurrent amount is obtained and the duty cycle is calculated and adjusted; According to the adjusted duty cycle, a pulse width modulation signal is generated to control the on-time of the insulated gate bipolar transistor and filter out the high-frequency component of the current.

6. The method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor according to claim 1, characterized in that: The circuit monitoring data is pre-processed and then input into a fault discriminator, which includes: Collect the fault current of the power router and build a fault current sample set; Dividing the fault current categories in the fault current sample set into samples, evaluating the sample balance of the divided categories, and supplementing the samples of the categories that do not meet the sample balance to meet the balance requirements of the samples of each category; Configure the training set, test set, and validation set according to the proportion of the data set; Using a support vector machine as a discriminator, using the training set, the test set, and the validation set to train and validate the discriminator, and adjusting hyperparameters; The discriminator is cross-validated using a validation set until an evaluation validation index is met, and a hyperparameter is determined to obtain the fault discriminator.

7. The method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor according to claim 1, characterized in that: After the fault identification information is obtained, the method further includes: Establishing a response relationship between a gate resistance value and a switching speed of the insulated gate bipolar transistor; Obtain the switch monitoring data set of the insulated gate bipolar transistor and fit the driving control relationship between the driving voltage amplitude, change rate and switching speed; According to the response relationship and the drive control relationship, a control list is constructed, which includes the control association relationship between the switching speed and the gate resistance value, the drive voltage amplitude, and the change rate; Classifying the switching speeds based on the switching speeds, and mapping the switching speed levels with the current isolation strategies; The associated switch speed level is matched using a matching current isolation strategy of the fault discrimination information to obtain a control parameter of the switch speed.

8. The method for isolating fault current of an electric energy router based on an insulated gate bipolar transistor according to claim 2, characterized in that: Calculating the fault current loss value of the output connection device includes: By formula: Calculate the fault current loss value of the output connection device, where I fault is the fault current, I normal is the normal working current, ∝, β is the weight coefficient, V fault is the fault voltage corresponding to the fault current, t fault is the duration of the fault current, p rated The rated power of the device.

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