A predictive system for preventing islanding operation of grid-connected circuit breakers

Abstract

This invention relates to the field of photovoltaic power generation technology, specifically to a grid-connected circuit breaker anti-islanding prediction system. The system includes a power supply module, a monitoring module, a main control module, a predictive analysis module, an execution module, a communication module, and a watchdog circuit. The power supply module provides the necessary power to each module. The monitoring module monitors grid parameters in real time. The main control module calculates and analyzes the data collected by the monitoring module in real time to determine if islanding occurs. The predictive analysis module predicts islanding based on historical and real-time data. The execution module performs grid disconnection or connection operations according to instructions from the main control module. The communication module transmits data with external devices. The watchdog circuit detects program anomalies. This invention enables real-time detection and efficient prediction of islanding, improving system response speed and accuracy, and reducing false detection and missed detection rates.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic power generation technology, and in particular to a grid-connected circuit breaker anti-islanding operation prediction system. Background Technology

[0002] With the development of new energy technologies, photovoltaic (PV) power generation systems have been widely used globally. PV systems are typically connected to the power grid via grid-connected circuit breakers to achieve efficient energy utilization. However, during the operation of PV systems, the islanding effect poses a serious safety hazard. The islanding effect refers to the situation where, even when the grid experiences a power outage, the PV system continues to supply power to the grid, causing certain areas of the grid to become isolated. The islanding effect not only threatens the stability and security of the power grid but may also endanger the safety of maintenance personnel.

[0003] Current islanding detection methods suffer from several technical challenges. First, these methods have limited accuracy and response speed, making them prone to false positives and false negatives, thus impacting system reliability and security. Second, most existing methods rely on a single detection mechanism, lacking intelligent analysis and comprehensive decision-making capabilities, and are unable to respond promptly and effectively to complex power grid environments and fluctuating photovoltaic power generation conditions. Furthermore, existing systems have limited communication capabilities, hindering remote monitoring and flexible data transmission, thus restricting system operability and maintainability. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides a system for predicting anti-islanding operation of grid-connected circuit breakers.

[0005] A predictive system for preventing islanding operation of a grid-connected circuit breaker includes a power supply module, a monitoring module, a main control module, a predictive analysis module, an execution module, a communication module, and a watchdog circuit, wherein;

[0006] The power supply module is used to provide the power required by each module, which includes a monitoring module, a main control module, a predictive analysis module, an execution module, a communication module, and a watchdog circuit.

[0007] The monitoring module includes multiple sensors for real-time monitoring of power grid parameter data, including voltage, current, and frequency;

[0008] The main control module includes a memory and a processor, which are used to store and execute control algorithms, and to determine whether there is an islanded operation by calculating and analyzing the data collected by the monitoring module in real time.

[0009] The predictive analysis module includes a predictive analysis unit and an artificial intelligence algorithm, which is used to predict the operation of isolated systems based on historical and real-time data.

[0010] The execution module performs the operation of disconnecting or connecting the power grid according to the instructions of the main control module. The execution module includes a circuit breaker control unit and a motor drive unit. When an islanded operation is detected, the grid-connected circuit breaker is disconnected.

[0011] The communication module includes a wired communication unit and a wireless communication unit for data transmission with external devices;

[0012] The watchdog circuit is used to detect whether the program is abnormal. If the program does not feed the watchdog, the watchdog circuit will restart the program and cause the grid-connected circuit breaker to trip for protection.

[0013] Optionally, the power module includes a regulated power supply and a backup power supply, wherein;

[0014] The regulated power supply includes:

[0015] Buck converter: The input voltage (e.g., AC power) is reduced to the operating voltage required by each module by a buck converter, including a switch-mode power converter (e.g., DC-DC buck converter);

[0016] Filter: Uses capacitors or inductors to filter voltage, remove noise and fluctuations in the power supply, and provide a stable voltage output;

[0017] Voltage regulator: The voltage is further stabilized by a linear voltage regulator to ensure that the voltage supplied to each module is accurate and stable;

[0018] The backup power supply includes:

[0019] Battery pack: includes a group of rechargeable batteries (such as lithium-ion batteries) to provide backup power in the event of a mains power outage or voltage abnormality;

[0020] Charging management circuit: Used to manage the charging and discharging process of the battery, ensuring that the battery has enough power when needed and extending battery life;

[0021] Switching circuit: When the mains power is interrupted, it automatically switches to backup battery power to ensure continuous system operation. The switching circuit usually uses relays or solid-state switches to achieve seamless switching.

[0022] Optionally, the monitoring module includes a data acquisition unit, which is used to acquire data from multiple sensors, including voltage, current, and frequency, and transmit the acquired data to the main control module. The multiple sensors specifically include:

[0023] Voltage sensor: The voltage sensor uses a resistive voltage divider to monitor the voltage data of the power grid in real time;

[0024] Current sensor: The current sensor uses a Hall effect sensor to monitor the current data of the power grid in real time. The Hall effect sensor measures current using the Hall effect principle.

[0025] Frequency sensor: It measures the frequency of the mains voltage or current by using a frequency counter or a dedicated frequency measurement chip to obtain frequency data.

[0026] Optionally, the main control module includes:

[0027] Data reception and preprocessing: The main control module receives power grid parameter data collected by the monitoring module and preprocesses the received data, including filtering, noise reduction and standardization, to ensure the accuracy and consistency of the data;

[0028] Islanding detection: Set normal range thresholds for voltage and frequency; trigger islanding detection when the range is exceeded.

[0029] Islanding detection: The processor executes the stored control algorithm to analyze the received power grid parameter data in real time, and uses the voltage frequency drift method to determine whether islanding occurs.

[0030] Generate control commands: If isolated operation is detected, generate corresponding control commands and transmit them to the execution module.

[0031] Optionally, the predictive analysis unit is used to perform data processing and analysis tasks, and the artificial intelligence algorithm is used to predict isolated operation based on a machine learning model, wherein the machine learning model is constructed using a support vector machine algorithm.

[0032] Optionally, the predictive analysis module specifically includes:

[0033] Data acquisition: Collect historical power grid parameter data, including historical voltage, current and frequency, and collect real-time power grid parameter data from the monitoring module;

[0034] Data preprocessing: Remove noise and outliers from historical and real-time power grid parameter data to ensure data accuracy, and convert the data to a uniform scale for easier algorithm processing. Extract key features from the data, including voltage fluctuations and frequency changes.

[0035] Model selection: Construct an island operation prediction model using the support vector machine algorithm;

[0036] Model training: Historical power grid parameter data are divided into training set and validation set. The training set data is used to train the model, and the validation set data is used to verify the model performance.

[0037] Real-time prediction: Input the real-time power grid parameter data collected by the monitoring module into the islanding operation prediction model. The model outputs the probability of islanding operation and determines whether to issue an early warning based on the preset threshold.

[0038] Warning signal: If the model outputs an island operation probability greater than a preset threshold, the predictive analysis module generates a warning signal;

[0039] Decision support: The predictive analysis module transmits early warning signals and prediction results to the main control module to assist the main control module in making decisions.

[0040] Optionally, the main control module further includes:

[0041] Receive early warning signals: The main control module receives early warning signals from the predictive analysis module. These early warning signals typically include the probability of islanded operation risk and other relevant data.

[0042] Data verification and confirmation: The main control module will verify and confirm the received warning signals, including:

[0043] Data integrity check: Ensure that the warning signal data is complete and error-free;

[0044] Data consistency check: Compare with real-time monitoring data to confirm the accuracy of the warning signal;

[0045] Data Analysis: The main control module combines real-time collected power grid parameter data to further analyze the risks of islanded operation, including:

[0046] Real-time data analysis: Analyze the voltage, current, and frequency data collected by the monitoring module again to confirm whether they are consistent with the information in the warning signal;

[0047] Comprehensive assessment: Combining historical data, real-time data, and early warning signals for a comprehensive assessment improves the accuracy of judgment;

[0048] Early warning status assessment: Assess the severity of the risk of islanded operation and generate control commands according to the predetermined control logic;

[0049] Execution control command: If the risk of islanded operation exceeds the set threshold, the main control module sends a disconnect command to the execution module, requesting the disconnection of the grid-connected circuit breaker;

[0050] Communication and recording: The main control module sends status information and warning information to external devices through the communication module.

[0051] Optionally, the circuit breaker control unit includes a control circuit and a solid-state switch, used to receive instructions from the main control module and control the state of the circuit breaker; the motor drive unit includes a motor, a drive circuit, and a mechanical linkage mechanism, used to drive the mechanical parts of the circuit breaker to realize the opening and closing operation of the circuit breaker; the execution module specifically includes:

[0052] Receive control commands: The execution module receives control commands from the main control module. These control commands include:

[0053] Operation type: Disconnect or connect the power grid;

[0054] Operation time: Immediate execution or delayed execution;

[0055] Instruction parsing and preparation: The execution module parses the received control instructions and performs corresponding preparatory work, including:

[0056] Check power supply status: Ensure that the power supply to the motor drive unit and circuit breaker control unit is normal;

[0057] Status confirmation: Confirm the current status of the circuit breaker (open or connected);

[0058] Execution Operation: Based on the parsed instructions, the execution module performs a disconnection or connection operation.

[0059] Optionally, the wired communication unit transmits data via a wired connection, including Ethernet, serial, and USB interfaces; the wireless communication unit transmits data via a wireless connection, including Wi-Fi, Bluetooth, and cellular networks. The communication module specifically includes:

[0060] Data acquisition and preparation: The communication module acquires the data to be transmitted, including status information (such as voltage, current, frequency, etc.), warning signals, and control commands;

[0061] Data transmission: Choose between wired or wireless transmission methods depending on the type of external device and communication requirements.

[0062] Optionally, the watchdog circuit includes a watchdog timer, a reset circuit, and a protection action execution unit. The watchdog timer monitors the program execution status and determines whether the program is running normally. The reset circuit restarts the system when a program abnormality is detected. The protection action execution unit executes a trip protection action when a program abnormality occurs. The specific working process of the watchdog circuit includes:

[0063] Initialization: The watchdog timer is initialized when the system starts up, setting the timing time and reset parameters;

[0064] Feeding the dog: During normal operation, the program will periodically send a feeding signal to the watchdog timer;

[0065] Program exception detection: If the program fails to perform the watchdog feeding operation within the predetermined time, the watchdog timer will consider the program to have encountered an exception;

[0066] System reset: The watchdog timer triggers a reset signal, and the reset circuit performs a reset operation;

[0067] Trip protection action: In case of program abnormality, in order to protect the safety of the power grid and photovoltaic system, the watchdog circuit will also perform a trip protection action.

[0068] The beneficial effects of this invention are:

[0069] This invention utilizes a support vector machine (SVM) algorithm combined with historical and real-time data to achieve real-time detection and efficient prediction of islanded operation status. Through data preprocessing, feature extraction, model training, and real-time prediction, the system can identify islanded operation risks in advance. In particular, based on the voltage frequency drift method, the application of the SVM algorithm further improves the accuracy and response speed of prediction, effectively reducing the false detection rate and missed detection rate, thus ensuring the stable operation of the power grid and photovoltaic power generation system.

[0070] In this invention, after receiving an early warning signal from the predictive analysis module, the main control module intelligently generates control commands through data verification and comprehensive analysis. The execution module, based on the commands from the main control module, utilizes the circuit breaker control unit and the motor drive unit to quickly perform operations to disconnect or connect to the power grid, ensuring rapid disconnection of the grid-connected circuit breaker when islanded operation is detected. Simultaneously, system reset and trip protection actions are automatically executed by the watchdog circuit in case of program abnormalities, ensuring the system can respond quickly and restore normal operation under various abnormal conditions, thus enhancing system safety and reliability.

[0071] This invention includes a communication module comprising a wired communication unit and a wireless communication unit, enabling flexible data transmission with external devices. Through wired connections via Ethernet, serial port, and USB, the system achieves stable and reliable data transmission; through wireless connections via Wi-Fi, Bluetooth, and cellular networks, the system adapts to various communication environments, enabling remote monitoring and management. Whether for local control or remote monitoring, the system can report status information and receive control commands in real time, ensuring that administrators can monitor system operation at any time and take timely measures, thus improving the system's operability and maintainability. Attached Figure Description

[0072] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0073] Figure 1 This is a schematic diagram of the system flow according to an embodiment of the present invention;

[0074] Figure 2 This is a schematic diagram of the predictive analysis module in an embodiment of the present invention. Detailed Implementation

[0075] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should also be noted that, to make the embodiments more comprehensive, the following embodiments are the best and preferred embodiments, and those skilled in the art can use other alternative methods to implement some well-known technologies; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0076] It should be noted that the use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the art.

[0077] Generally, terms can be understood at least partly from their use in context. For example, depending at least partly on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood not necessarily to convey an exclusive set of factors, but rather, alternatively, depending at least partly on the context, to allow for the presence of other factors that are not necessarily explicitly described.

[0078] like Figures 1-2 As shown, a grid-connected circuit breaker anti-islanding operation prediction system includes a power supply module, a monitoring module, a main control module, a predictive analysis module, an execution module, a communication module, and a watchdog circuit, wherein;

[0079] The power supply module provides the power required by each module, which includes a monitoring module, a main control module, a predictive analysis module, an execution module, a communication module, and a watchdog circuit.

[0080] The monitoring module includes multiple sensors for real-time monitoring of power grid parameter data, including voltage, current, and frequency;

[0081] The main control module includes a memory and a processor, which are used to store and execute control algorithms. It determines whether there is an isolated operation by calculating and analyzing the data collected by the monitoring module in real time.

[0082] The predictive analytics module includes predictive analytics units and artificial intelligence algorithms, used to predict the operation of isolated systems based on historical and real-time data;

[0083] The execution module performs the operation of disconnecting or connecting the power grid according to the instructions of the main control module. The execution module includes a circuit breaker control unit and a motor drive unit. When islanded operation is detected, the grid-connected circuit breaker is disconnected.

[0084] The communication module includes a wired communication unit and a wireless communication unit for data transmission with external devices;

[0085] The watchdog circuit is used to detect whether there is an abnormality in the program. If the program does not feed the watchdog, the watchdog circuit will restart the program and cause the grid-connected circuit breaker to trip for protection.

[0086] The power module includes a regulated power supply and a backup power supply, wherein;

[0087] Regulated power supplies include:

[0088] Buck converter: The input voltage (e.g., AC power) is reduced to the operating voltage required by each module by a buck converter, including a switch-mode power converter (e.g., DC-DC buck converter);

[0089] Filter: Uses capacitors or inductors to filter voltage, remove noise and fluctuations in the power supply, and provide a stable voltage output;

[0090] Voltage regulator: The voltage is further stabilized by a linear voltage regulator to ensure that the voltage supplied to each module is accurate and stable;

[0091] Backup power supplies include:

[0092] Battery pack: includes a group of rechargeable batteries (such as lithium-ion batteries) to provide backup power in the event of a mains power outage or voltage abnormality;

[0093] Charging management circuit: Used to manage the charging and discharging process of the battery, ensuring that the battery has enough power when needed and extending battery life;

[0094] Switching circuit: When the mains power is interrupted, it automatically switches to backup battery power to ensure continuous system operation. The switching circuit usually uses relays or solid-state switches to achieve seamless switching.

[0095] The working principle of the power module is as follows:

[0096] Under normal circumstances, the mains power provides a stable operating voltage to each module of the system through a step-down circuit, filter and regulator. At the same time, the charging management circuit charges the backup battery to keep it in optimal condition.

[0097] When the mains power is interrupted or the voltage is abnormal, the switching circuit will quickly switch to backup battery power to provide operating voltage for each module of the system and ensure the continuous operation of the system.

[0098] The monitoring module includes a data acquisition unit, which collects data from multiple sensors, including voltage, current, and frequency, and transmits the collected data to the main control module. The multiple sensors specifically include:

[0099] Voltage sensor: The voltage sensor uses a resistive voltage divider to monitor the voltage data of the power grid in real time;

[0100] Current sensor: The current sensor uses a Hall effect sensor to monitor the current data of the power grid in real time. The Hall effect sensor measures current using the Hall effect principle.

[0101] Frequency sensor: It measures the frequency of the mains voltage or current by using a frequency counter or a dedicated frequency measurement chip to obtain frequency data.

[0102] The main control module includes:

[0103] Data reception and preprocessing: The main control module receives power grid parameter data collected by the monitoring module and preprocesses the received data, including filtering, noise reduction and standardization, to ensure the accuracy and consistency of the data;

[0104] Islanding detection: Set normal range thresholds for voltage and frequency; trigger islanding detection when the range is exceeded.

[0105] Islanding detection: The processor executes the stored control algorithm to analyze the received power grid parameter data in real time, and uses the voltage frequency drift method to determine whether islanding occurs.

[0106] The steps for determining whether islanding occurs using the voltage frequency drift method are as follows:

[0107] (1) Voltage detection formula: Let the normal range of voltage be V. min To V max The real-time voltage is V(t);

[0108] V min ≤V(t)≤V max ;

[0109] If: V(t) <V min Or V(t)>V max If so, it is determined to be operating in an isolated environment;

[0110] (2) Frequency detection formula: Set the normal range of frequency as f min to f max The real-time frequency is f(t);

[0111] f min ≤f(t)≤f max ;

[0112] If: f(t) <f min Or f(t)>f max If so, it is determined to be operating in an isolated environment;

[0113] Generate control commands: If isolated operation is detected, generate corresponding control commands and transmit them to the execution module.

[0114] The predictive analytics unit is used to perform data processing and analysis tasks, and artificial intelligence algorithms are used to predict isolated operations based on machine learning models. The machine learning models are constructed using the support vector machine algorithm.

[0115] The predictive analytics module specifically includes:

[0116] Data acquisition: Collect historical power grid parameter data, including historical voltage, current and frequency, and collect real-time power grid parameter data from the monitoring module;

[0117] Data preprocessing: Remove noise and outliers from historical and real-time power grid parameter data to ensure data accuracy, and convert the data to a uniform scale for easier algorithm processing. Extract key features from the data, including voltage fluctuations and frequency changes.

[0118] Data normalization: Converting data to a uniform scale. Let the original voltage data be V(t), and the normalized voltage data be V′(t), then it can be expressed as:

[0119] Among them, V min and V max These are the minimum and maximum values ​​of the voltage data, respectively.

[0120] Model selection: Construct an island operation prediction model using the support vector machine algorithm;

[0121] Model training: Historical power grid parameter data are divided into training set and validation set. The training set data is used to train the model, and the validation set data is used to verify the model performance.

[0122] Support Vector Machines (SVMs) categorize data into isolated runs and non-isolated runs by finding the optimal hyperplane for the training dataset. Where x i It is an eigenvector, y i The label is 1 for isolated instances and -1 for non-isolated instances. The optimization objective of the support vector machine is:

[0123] Under constraints: y i(w·x i +b)≥1-ξ i ,ξ i ≥0;

[0124] Where w is the weight vector, b is the bias, and ξ is the weight vector. i C is the slack variable, and C is the regularization parameter.

[0125] Kernel Function Selection: To handle nonlinear data, Support Vector Machines (SVMs) introduce kernel functions to map the data to a high-dimensional space. Commonly used kernel functions include linear kernels, polynomial kernels, and radial basis function (RBF) kernels. In this invention, the RBF kernel is selected, and its formula is as follows:

[0126] K(x i |x j )=exp(-γx i -x j 2 ), where γ is the kernel parameter;

[0127] Real-time prediction: Input the real-time power grid parameter data collected by the monitoring module into the islanding operation prediction model. The model outputs the probability of islanding operation and determines whether to issue an early warning based on the preset threshold.

[0128] The decision function of the trained island operation prediction model is:

[0129] Where, α i They are Lagrange multipliers;

[0130] Calculation of the probability of isolated operation: Calculating real-time data x using a decision function. real Predicted values:

[0131]

[0132] If f(x) real If )>0, it is predicted to be an island operation; otherwise, it is predicted to be a non-island operation.

[0133] To more intuitively represent the prediction results, the decision values ​​are converted into probabilities using a logistic regression function, expressed as follows:

[0134] Warning signal: If the model outputs an island operation probability greater than a preset threshold, the predictive analysis module generates a warning signal;

[0135] Decision support: The predictive analysis module transmits early warning signals and prediction results to the main control module to assist the main control module in making decisions.

[0136] The main control module further includes:

[0137] Receive early warning signals: The main control module receives early warning signals from the predictive analysis module. These early warning signals typically include the probability of islanded operation risk and other relevant data.

[0138] Data verification and confirmation: The main control module will verify and confirm the received warning signals, including:

[0139] Data integrity check: Ensure that the warning signal data is complete and error-free;

[0140] Data consistency check: Compare with real-time monitoring data to confirm the accuracy of the warning signal;

[0141] Data Analysis: The main control module combines real-time collected power grid parameter data to further analyze the risks of islanded operation, including:

[0142] Real-time data analysis: Analyze the voltage, current, and frequency data collected by the monitoring module again to confirm whether they are consistent with the information in the warning signal;

[0143] Comprehensive assessment: Combining historical data, real-time data, and early warning signals for a comprehensive assessment improves the accuracy of judgment;

[0144] Early warning status assessment: Assess the severity of the risk of islanded operation and generate control commands according to the predetermined control logic;

[0145] Execution control command: If the risk of islanded operation exceeds the set threshold, the main control module sends a disconnect command to the execution module, requesting the disconnection of the grid-connected circuit breaker;

[0146] Communication and recording: The main control module sends status information and early warning information to external devices through the communication module to ensure that managers can keep abreast of the system's operating status.

[0147] Example: Suppose the main control module receives an early warning signal from the predictive analysis module, and the early warning signal indicates that the probability of islanded operation risk is 80%;

[0148] (1) Data verification and confirmation: Check the integrity and consistency of the warning signal data, compare it with real-time data, and confirm the accuracy of the warning signal;

[0149] (2) Further analysis: Analyze the real-time voltage, current and frequency data again, and combine historical data and real-time data to comprehensively assess the risk of islanded operation;

[0150] (3) Decision generation: Assess the severity of the islanding operation risk (80%), and generate instructions to disconnect the grid-connected circuit breaker according to the predetermined control logic;

[0151] (4) Execute control commands: Send a disconnect command to the execution module, and the execution module disconnects the grid-connected circuit breaker to isolate the photovoltaic system from the power grid;

[0152] (5) Communication and recording: Send early warning information and status updates to the remote monitoring system, and record early warning signals, analysis results, decision-making and execution status.

[0153] The circuit breaker control unit includes a control circuit and a solid-state switch, used to receive instructions from the main control module and control the state of the circuit breaker. The motor drive unit includes a motor, a drive circuit, and a mechanical linkage mechanism, used to drive the mechanical parts of the circuit breaker and realize the opening and closing operations of the circuit breaker. The execution module specifically includes:

[0154] Receive control commands: The execution module receives control commands from the main control module. These control commands include:

[0155] Operation type: Disconnect or connect the power grid;

[0156] Operation time: Immediate execution or delayed execution;

[0157] Instruction parsing and preparation: The execution module parses the received control instructions and performs corresponding preparatory work, including:

[0158] Check power supply status: Ensure that the power supply to the motor drive unit and circuit breaker control unit is normal;

[0159] Status confirmation: Confirm the current status of the circuit breaker (open or connected);

[0160] Execution Operation: Based on the parsed instructions, the execution module performs a disconnection or connection operation;

[0161] The disconnection operation includes:

[0162] (1) Control signal transmission: The circuit breaker control unit sends a disconnection signal;

[0163] (2) Motor drive: After receiving the signal, the motor drive unit drives the motor to perform the disconnection operation, thereby causing the mechanical part of the circuit breaker to disconnect the power grid connection;

[0164] (3) Status feedback: The circuit breaker control unit monitors the status of the circuit breaker and feeds back the operation results to the main control module;

[0165] The connection operation includes:

[0166] (1) Control signal transmission: The circuit breaker control unit sends a connection signal;

[0167] (2) Motor drive: After receiving the signal, the motor drive unit drives the motor to perform the connection operation, thereby driving the mechanical part of the circuit breaker to connect to the power grid;

[0168] (3) Status feedback: The circuit breaker control unit monitors the status of the circuit breaker and feeds back the operation results to the main control module;

[0169] Specific examples:

[0170] Suppose that the execution module receives a disconnect command from the main control module, which requires the immediate disconnection of the grid-connected circuit breaker;

[0171] (1) Receiving control commands: The execution module receives disconnect commands through the communication interface. The command content is as follows:

[0172] Operation type: Disconnect power grid;

[0173] Operation time: Execute immediately;

[0174] (2) Instruction parsing and preparation:

[0175] Parsing the instruction: Confirm that the instruction is a disconnect operation and needs to be executed immediately;

[0176] Check power status: Confirm that the power supply to the motor drive unit and circuit breaker control unit is normal;

[0177] Status Confirmation: Confirm that the current status of the circuit breaker is connected;

[0178] (3) Perform the operation:

[0179] Control signal transmission: The circuit breaker control unit sends a disconnect signal;

[0180] Motor drive: The motor drive unit receives a disconnection signal, starts the motor, and drives the mechanical part of the circuit breaker to disconnect the power grid connection;

[0181] Status feedback: The circuit breaker control unit monitors the actual status of the circuit breaker and, after confirming that the disconnection was successful, feeds back the operation result to the main control module.

[0182] The wired communication unit transmits data via wired connections, including Ethernet, serial, and USB interfaces. The wireless communication unit transmits data wirelessly via Wi-Fi, Bluetooth, and cellular networks. The communication module specifically includes:

[0183] Data acquisition and preparation: The communication module acquires the data to be transmitted, including status information (such as voltage, current, frequency, etc.), warning signals, and control commands;

[0184] Data transmission: Select wired or wireless transmission methods based on the type of external device and communication requirements;

[0185] Wired transmission methods include:

[0186] Data packaging: Packing data into a format suitable for transmission (such as TCP / IP packets, serial port data frames);

[0187] Data transmission: Data is transmitted to external devices via Ethernet interface, serial port or USB interface;

[0188] Data reception: Receives data or instructions returned by external devices, and parses and processes them;

[0189] Wireless transmission methods include:

[0190] Data packaging: Packing data into a format suitable for wireless transmission (such as Wi-Fi data packets, Bluetooth data packets);

[0191] Data transmission: Send data to external devices via Wi-Fi, Bluetooth, or cellular network modules;

[0192] Data reception: Receive data or instructions returned by external devices, and parse and process them.

[0193] The watchdog circuit includes a watchdog timer, a reset circuit, and a protection action execution unit. The watchdog timer monitors the program execution status and determines whether the program is running normally. The reset circuit restarts the system when a program abnormality is detected. The protection action execution unit executes trip protection actions when a program abnormality occurs. The specific working process of the watchdog circuit includes:

[0194] Initialization: The watchdog timer is initialized when the system starts up, setting the timing time and reset parameters. Typically, the timing time is set to the range within which the program can complete one watchdog feeding operation under normal system conditions.

[0195] Watchdog feeding operation: During normal operation, the program will periodically send a watchdog feeding signal (i.e., reset the watchdog timer) to the watchdog timer. The frequency of the watchdog feeding operation should be guaranteed to be at least once within the time interval of the watchdog timer.

[0196] Program anomaly detection: If the program fails to perform the watchdog feeding operation within the predetermined time, the watchdog timer will consider the program to have encountered an anomaly. The specific detection steps are as follows:

[0197] Timer control: The watchdog timer starts counting down. If no dog-feeding signal is received within the predetermined time, the timer expires.

[0198] Reset Detection: If a timeout is detected, the program is deemed abnormal, and a reset operation is triggered.

[0199] System Reset: The watchdog timer triggers a reset signal, and the reset circuit performs a reset operation, with the following steps:

[0200] Reset signal generation: The watchdog timer sends a reset signal;

[0201] Reset control: After receiving a reset signal, the reset circuit performs a system reset, restarts the processor and related modules, and reinitializes the system;

[0202] Trip protection action: In the event of a program malfunction, in order to protect the safety of the power grid and photovoltaic system, the watchdog circuit will also execute a trip protection action, the steps of which are as follows:

[0203] Control signal generation: The watchdog timer sends a trip control signal;

[0204] Circuit breaker control: After receiving a trip signal, the circuit breaker control unit performs a disconnection operation to disconnect the grid-connected circuit breaker;

[0205] Status feedback: The circuit breaker control unit will send disconnection status feedback to the main control module to confirm that the tripping operation has been executed;

[0206] Specific implementation example:

[0207] Set the watchdog timer interval to 500ms, and the program will perform a watchdog feeding operation every 100ms during normal operation.

[0208] Under normal circumstances:

[0209] (1) Program execution: The program runs normally, sending a dog-feeding signal every 100ms to reset the watchdog timer;

[0210] (2) Watchdog timer: The watchdog timer resets its countdown every time a dog-feeding signal is received, and will not trigger a timeout;

[0211] (3) System status: The system is running normally and the watchdog timer has not triggered a reset operation;

[0212] In case of program exception:

[0213] (1) Program execution: Due to program abnormalities (such as infinite loop, crash, etc.), no dog feed signal was sent within 500ms;

[0214] (2) Watchdog timer: If the watchdog timer does not receive a feed signal within 500ms, the timer times out and the program is judged to be abnormal;

[0215] (3) System Reset: The watchdog timer triggers a reset signal, and the reset circuit performs a system reset, restarting the processor and related modules;

[0216] (4) Trip protection: The watchdog timer sends a trip control signal, and the circuit breaker control unit performs a disconnection operation to disconnect the grid-connected circuit breaker;

[0217] (5) Status feedback: The circuit breaker control unit will feed back the disconnection status to the main control module to confirm that the tripping operation has been executed;

[0218] "Program" refers to the control software or firmware in the system. This program usually runs on the processor of the main control module and includes a series of tasks and operations, such as data acquisition, processing, control decision-making, and communication.

[0219] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0220] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A system for predicting islanding operation of grid-connected circuit breakers, characterized in that, It includes a power supply module, a monitoring module, a main control module, a predictive analytics module, an execution module, a communication module, and a watchdog circuit, among which; The power supply module is used to provide the power required by each module, which includes a monitoring module, a main control module, a predictive analysis module, an execution module, a communication module, and a watchdog circuit. The monitoring module includes multiple sensors for real-time monitoring of power grid parameter data, including voltage, current, and frequency; The main control module includes a memory and a processor, which are used to store and execute control algorithms, and to determine whether there is an islanded operation by calculating and analyzing the data collected by the monitoring module in real time. The predictive analysis module includes a predictive analysis unit and an artificial intelligence algorithm, which is used to predict the operation of isolated systems based on historical and real-time data. The execution module performs the operation of disconnecting or connecting the power grid according to the instructions of the main control module. The execution module includes a circuit breaker control unit and a motor drive unit. When an islanded operation is detected, the grid-connected circuit breaker is disconnected. The communication module includes a wired communication unit and a wireless communication unit for data transmission with external devices; The watchdog circuit is used to detect whether the program is abnormal. If the program does not feed the watchdog, the watchdog circuit will restart the program and cause the grid-connected circuit breaker to trip for protection. The predictive analysis module specifically includes: Data acquisition: Collect historical power grid parameter data, including historical voltage, current and frequency, and collect real-time power grid parameter data from the monitoring module; Data preprocessing: Remove noise and outliers from historical and real-time power grid parameter data, and convert them to a uniform scale to facilitate algorithm processing. Extract key features from the data, including voltage fluctuations and frequency changes. Model selection: Construct an island operation prediction model using the support vector machine algorithm; Model training: Historical power grid parameter data are divided into training set and validation set. The training set data is used to train the model, and the validation set data is used to verify the model performance. Real-time prediction: Input the real-time power grid parameter data collected by the monitoring module into the islanding operation prediction model. The model outputs the probability of islanding operation and determines whether to issue an early warning based on the preset threshold. Warning signal: If the model outputs an island operation probability greater than a preset threshold, the predictive analysis module generates a warning signal; Decision support: The predictive analysis module transmits early warning signals and prediction results to the main control module to assist the main control module in making decisions; The main control module further includes: Receiving early warning signals: The main control module receives early warning signals from the predictive analysis module; Data verification and confirmation: The main control module will verify and confirm the received warning signals; Data analysis: The main control module combines real-time collected power grid parameter data to further analyze the risks of islanded operation; Early warning status assessment: Assess the severity of the risk of islanded operation and generate control commands according to the predetermined control logic; Execution control command: If the risk of islanded operation exceeds the set threshold, the main control module sends a disconnect command to the execution module, requesting the disconnection of the grid-connected circuit breaker; Communication and recording: The main control module sends status information and warning information to external devices through the communication module.

2. The anti-islanding operation prediction system for grid-connected circuit breakers according to claim 1, characterized in that, The power module includes a regulated power supply and a backup power supply, wherein; The regulated power supply includes: Buck converter: The input voltage is reduced to the operating voltage required by each module through the buck converter. Filter: Uses capacitors or inductors to filter voltage and remove noise and fluctuations in the power supply; Voltage regulator: Further stabilizes the voltage through a linear voltage regulator; The backup power supply includes: Battery pack: includes a set of rechargeable batteries to provide backup power in the event of a mains power outage or voltage abnormality; Charging management circuit: Used to manage the charging and discharging process of the battery; Switching circuit: Automatically switches to backup battery power when mains power is interrupted.

3. The anti-islanding operation prediction system for grid-connected circuit breakers according to claim 2, characterized in that, The monitoring module includes a data acquisition unit, which collects data from multiple sensors, including voltage, current, and frequency, and transmits the collected data to the main control module. The multiple sensors specifically include: Voltage sensor: The voltage sensor uses a resistive voltage divider to monitor the voltage data of the power grid in real time; Current sensor: The current sensor uses a Hall effect sensor to monitor the current data of the power grid in real time; Frequency sensor: It measures the frequency of the mains voltage or current by using a frequency counter or a dedicated frequency measurement chip to obtain frequency data.

4. The anti-islanding operation prediction system for grid-connected circuit breakers according to claim 3, characterized in that, The main control module includes: Data reception and preprocessing: The main control module receives power grid parameter data collected by the monitoring module and preprocesses the received data, including filtering, noise reduction and standardization; Islanding detection: Set normal range thresholds for voltage and frequency; trigger islanding detection when the range is exceeded. Islanding detection: The processor executes the stored control algorithm to analyze the received power grid parameter data in real time, and uses the voltage frequency drift method to determine whether islanding occurs. Generate control commands: If isolated operation is detected, generate corresponding control commands and transmit them to the execution module.

5. The anti-islanding operation prediction system for grid-connected circuit breakers according to claim 4, characterized in that, The predictive analysis unit is used to perform data processing and analysis tasks, and the artificial intelligence algorithm is used to predict isolated operation based on the machine learning model, which is constructed using the support vector machine algorithm.

6. The anti-islanding operation prediction system for grid-connected circuit breakers according to claim 5, characterized in that, The circuit breaker control unit includes a control circuit and a solid-state switch, used to receive instructions from the main control module and control the state of the circuit breaker. The motor drive unit includes a motor, a drive circuit, and a mechanical linkage mechanism, used to drive the mechanical parts of the circuit breaker to realize the opening and closing operation of the circuit breaker. The execution module specifically includes: Receive control commands: The execution module receives control commands from the main control module; Instruction parsing and preparation: The execution module parses the received control instructions and performs the corresponding preparatory work; Execution Operation: Based on the parsed instructions, the execution module performs a disconnection or connection operation.

7. The anti-islanding operation prediction system for grid-connected circuit breakers according to claim 6, characterized in that, The wired communication unit transmits data via a wired connection, including Ethernet, serial, and USB interfaces. The wireless communication unit transmits data via a wireless connection, including Wi-Fi, Bluetooth, and cellular networks. The communication module specifically includes: Data acquisition and preparation: The communication module acquires the data to be transmitted, including status information, warning signals, and control commands; Data transmission: Choose between wired or wireless transmission methods depending on the type of external device and communication requirements.

8. The anti-islanding operation prediction system for grid-connected circuit breakers according to claim 1, characterized in that, The watchdog circuit includes a watchdog timer, a reset circuit, and a protection action execution unit. The watchdog timer monitors program execution and determines whether the program is running normally. The reset circuit restarts the system when a program abnormality is detected. The protection action execution unit executes trip protection actions when a program abnormality occurs. The specific working process of the watchdog circuit includes: Initialization: The watchdog timer is initialized when the system starts up, setting the timing time and reset parameters; Feeding the dog: During normal operation, the program will periodically send a feeding signal to the watchdog timer; Program exception detection: If the program fails to perform the watchdog feeding operation within the predetermined time, the watchdog timer will consider the program to have encountered an exception; System reset: The watchdog timer triggers a reset signal, and the reset circuit performs a reset operation; Trip protection action: In case of program abnormality, in order to protect the safety of the power grid and photovoltaic system, the watchdog circuit will also perform a trip protection action.

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