Automatic compensation load balancing system and method for connecting distributed power supply to three-phase unbalanced power grid

Abstract

The invention discloses an automatic compensation load balancing system and method for connecting distributed power supplies to a three-phase unbalanced power grid, and the system comprises a plurality of distributed power supplies and a load balancing control module, and each distributed power supply and load balancing control module is provided with a wireless ad hoc network communication module. All the distributed power supplies and the load balance control modules form a communication network through respective wireless ad hoc network communication modules; each wireless ad hoc network communication module is connected with the load balance control module through an edge calculation module, and in the edge calculation module, a double-buffering mechanism is adopted for data processing; the load balance control module comprises a load balance controller, a compensation current adjusting unit and a load distribution unit; through the application of the automatic compensation load balancing device, the problem of three-phase imbalance of the power grid is effectively solved, the situations that the power supply efficiency is reduced and the equipment loss is increased are reduced, and the economical efficiency and the reliability of power grid operation are improved.

Description

Technical Field

[0001] This invention mainly relates to the field of smart grid technology, specifically to an automatic compensation load balancing device for distributed power sources accessing a three-phase unbalanced power grid based on wireless self-organizing networks and edge computing. Background Technology

[0002] In modern power systems, three-phase imbalance and load fluctuations are significant factors affecting power supply efficiency and stability. Three-phase imbalance leads to reduced power supply efficiency and increased equipment losses, while large load fluctuations result in poor power supply stability, impacting power quality for users, increasing grid losses, raising power supply costs, and ultimately affecting the economic benefits of power supply companies. Therefore, achieving automatic compensation for three-phase imbalance and load balancing has become an important research direction in the field of power system technology.

[0003] Currently, the main measures taken to address the problems of three-phase imbalance and load fluctuations in the power grid include manually adjusting load distribution and using wired communication technology for load monitoring and control. For example, manually adjusting load distribution can achieve a certain degree of balance in the three-phase load; using wired communication technology allows for real-time monitoring of the power grid load and load control. However, these methods have some significant shortcomings.

[0004] While existing technologies have improved the problems of three-phase imbalance and load fluctuation in power grids to some extent, several issues and shortcomings remain. First, manual load allocation adjustments are inefficient, struggle to cope with rapidly changing load conditions, and are susceptible to human error. Second, wired communication technologies are complex and costly, and difficult to adapt to three-phase unbalanced distribution areas with distributed power sources. Furthermore, existing solutions have limitations in practical applications, failing to achieve rapid and accurate three-phase load balancing and failing to meet the power supply reliability and power quality requirements of three-phase unbalanced distribution areas with distributed power sources. Therefore, developing a novel automatic compensation and load balancing method for three-phase imbalance in power grids has significant practical importance and application value. Summary of the Invention

[0005] The present invention aims to solve three technical problems, namely: 1) Manual load allocation adjustment is inefficient, difficult to cope with rapidly changing load conditions, and easily affected by human factors. 2) Wired communication technology has technical problems such as complex wiring, high cost, and difficulty in adapting to three-phase unbalanced transformer areas with distributed power supply access; 3) Existing technical solutions are difficult to achieve rapid and accurate balancing of three-phase loads in the power grid, and are unable to meet the power supply reliability and power quality requirements of three-phase unbalanced distribution areas connected by distributed power sources.

[0006] To solve the above problems, the present invention is achieved through the following technical solution: An automatic compensation load balancing system for distributed power sources connected to a three-phase unbalanced power grid includes multiple distributed power sources and load balancing control modules. Each distributed power source and load balancing control module is equipped with a wireless self-organizing network communication module, and all distributed power sources and load balancing control modules form a communication network through their respective wireless self-organizing network communication modules. Each wireless ad hoc network communication module is connected to the load balancing control module through the edge computing module. In the edge computing module, a double buffering mechanism is used for data processing, with two buffers set up: one for receiving data collected by the underlying nodes in real time, and the other for data processing. The load balancing control module includes a load balancing controller, a compensation current adjustment unit, and a load distribution unit. The load balancing controller receives current and voltage information from each distributed power source and the power consumption of the load. It then predicts the future power generation of each distributed power source and adjusts the compensation strategy in advance to ensure that the three-phase load remains balanced when distributed power sources are connected or disconnected. The load distribution unit adjusts the load distribution according to the instructions of the load balancing controller to achieve three-phase load balance. The compensation current adjustment unit adjusts the compensation current according to the instructions of the load balancing controller.

[0007] Distributed power sources include one or more of photovoltaic power generation systems, wind power generation systems, and biomass power generation systems.

[0008] The layered architecture of the wireless self-organizing network communication network for distributed power sources includes: The first layer is the application and management layer, which includes the SCADA / EMS (Site Monitoring and Control System) and the cloud platform / central control center. The SCADA / EMS is located in the local dispatch center and is responsible for real-time monitoring and advanced applications. The load balancing control module is part of the SCADA / EMS. The cloud platform / central control center performs big data analysis, long-term performance evaluation, and cross-site coordination. The second layer is the network backbone layer, which includes a main aggregation gateway and at least one regional aggregation gateway. The main aggregation gateway is deployed in the control center and serves as the network's main exit and root clock source. The regional aggregation gateways are geographically distributed and form a fixed mesh backbone network through wired Ethernet or directional wireless microwave. The third layer is the network access layer. This network adopts a clustered hybrid topology, which includes multiple clusters. Each cluster includes a cluster head node, and each cluster head node communicates directly with at least one member node. The cluster head node is a large-scale energy storage converter or a communication concentrator; the cluster head node manages members within the cluster, aggregates and compresses data within the cluster, performs local collaborative computing, and acts as a gateway to connect to the backbone layer or other cluster heads. The member nodes include photovoltaic inverters, energy storage converters, wind turbine controllers, or electricity meters. The fourth layer is the device layer, which is the network's sensing and execution terminal. It consists of various distributed power intelligent sensing terminals with built-in or external wireless communication modules.

[0009] A control method for an automatic compensation load balancing system for distributed generation connected to a three-phase unbalanced power grid includes the following steps: Step 1: A wireless self-organizing network communication module is installed on each of the distributed power supply and load balancing control modules to automatically form a communication network; Step 2: When any distributed power source is connected or disconnected, the status information of the distributed power source is quickly transmitted to the automatic compensation load balancing device through a wireless self-organizing network; the status information includes the power generation, voltage, and current of the distributed power source. Step 3: The load balancing control module adjusts the compensation strategy of the device in advance based on the power generation forecast information of the distributed power source and the grid load situation to ensure that the three-phase load remains balanced when the distributed power source is connected and disconnected; the compensation strategy includes load distribution adjustment and compensation current adjustment.

[0010] Step 2 specifically includes: Step 2.1: Establish a layered architecture for the wireless self-organizing network communication network of distributed power sources; Step 2.1.1: Use encryption algorithms to encrypt data transmission between nodes in the layered architecture of the wireless self-organizing network communication network of the distributed power source; Step 2.1.2: Each wireless ad hoc network module is equipped with multiple communication channels. The wireless ad hoc network module monitors the signal strength and signal-to-noise ratio of the channels in real time, and then adaptively selects the best communication channel. Step 2.2: Each wireless ad hoc network communication module is connected to the load balancing control module through the edge computing module; Step 2.2.1: The edge computing module adopts a double buffering mechanism for data processing, setting up two buffers: one for receiving data collected by the underlying nodes in real time, and the other for data processing. Step 2.2.2: The edge computing module makes local decisions on the data according to preset rules, and only uploads the data to the upper-level node when necessary; the local decision rules include load imbalance exceeding 5% and voltage fluctuation exceeding 10%.

[0011] In step 2.1.1, the encryption algorithm adopts either a symmetric encryption algorithm or a quantum encryption algorithm. When using a quantum encryption algorithm, before data transmission, the quantum key distribution device uses the generated quantum key to encrypt the data, and the receiver uses the corresponding key to decrypt it. A quantum random number generator can also be integrated into the wireless self-organizing network communication module to generate random numbers required for encryption.

[0012] Step 3 includes: Step 3.1: The compensation current adjustment unit adjusts the compensation current according to the instructions of the load balance controller to reduce the impact on the power grid; the compensation current adjustment unit includes an instruction generation layer, a core control layer and a power execution layer; The instruction generation layer includes a detection and calculation module and a reference current generation module. The detection and calculation module extracts harmonic / reactive current. Based on instantaneous reactive power theory, the three-phase current is decomposed into instantaneous active current (ip) and reactive current (iq) through α-β coordinate transformation. The reactive current component directly reflects the system imbalance, and the calculation formula is as follows: Among them, u α Let u be the voltage value in the α coordinate. β The voltage value in the β coordinate; The reference current generation module generates a reference command current 𝑖_𝑟𝑒𝑓; then the instantaneous active current, reactive current and reference command current 𝑖_𝑟𝑒𝑓 are sent to the comparator in the core control layer; The core control layer includes a comparator, a current controller, a modulation algorithm module, and a drive signal generation module; wherein, the comparator compares the reference command current 𝑖_𝑟𝑒𝑓 with the actual output current 𝑖_𝑜𝑢𝑡 detected by the sensor in real time, and generates an instantaneous current error signal 𝑒=𝑖_𝑟𝑒𝑓−𝑖_𝑜𝑢𝑡; The current controller receives the instantaneous current error signal S and calculates a control voltage signal β through a control algorithm, with the goal of making the error S quickly approach zero. The control algorithm is as follows: i) Use a second-order generalized integrator to separate the positive-sequence, negative-sequence, and zero-sequence currents; ii) Compensation strategy: Prioritize compensating negative-sequence components, then process zero-sequence components, combined with hysteresis control or space vector modulation techniques; The modulation module converts the continuous-time analog voltage command output by the current controller into a discrete pulse width modulation signal that can be executed by the power switching device, and outputs PWM pulses through the drive signal generation module; The PWM pulse output by the drive signal generation module enters the power actuator, which includes a power converter. The power converter performs level conversion, isolation and power amplification on the PWM pulse to generate a gate signal to drive switching devices such as IGBTs. The gate signal causes the output module to output a compensation current to the power grid. Step 3.2: The load distribution unit adjusts the load distribution according to the instructions of the load balance controller to achieve the balance of the three-phase load.

[0013] Compared with existing technologies, this invention has the following beneficial effects: 1. Improved power supply efficiency and reduced equipment losses: By applying an automatic load balancing device, the three-phase imbalance problem of the power grid is effectively addressed, reducing power supply efficiency and increasing equipment losses, thus improving the economy and reliability of power grid operation. 2. Enhanced power supply stability and power quality: Addressing the problem of large power grid load fluctuations, this solution improves power supply stability and reduces the impact on user power quality through specialized control strategies and collaborative control mechanisms. 3. Reduced grid losses and power supply costs: By optimizing load allocation and improving power supply reliability, grid losses are reduced, power supply costs are lowered, and the economic benefits of power supply companies are improved. 4. Improved response speed and accuracy of load allocation: Utilizing wireless ad hoc network communication technology and edge computing nodes, fast and accurate load allocation is achieved, adapting to rapidly changing load conditions and reducing the impact of human factors. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the principle of the present invention; Figure 2 This is the timing diagram for the distributed power supply dynamic balance control of the present invention; Figure 3 This is a timing diagram for dynamic compensation control of distributed power sources. Figure 4 A layered architecture diagram of a wireless self-organizing network communication network for distributed power sources; Figure 5 Here is a structural diagram of the compensation current adjustment unit; Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0017] like Figure 1 As shown, an automatic compensation load balancing system for distributed power sources connected to a three-phase unbalanced power grid includes multiple distributed power sources and load balancing control modules. Each distributed power source and load balancing control module is equipped with a wireless ad hoc network communication module. Thus, all distributed power sources and load balancing control modules form a communication network through their respective wireless ad hoc network communication modules. Preferably, the communication distance of the wireless ad hoc network module is 1000 meters, and the communication rate is 100 Mbps.

[0018] In this patent application, distributed power sources include one or more of photovoltaic power generation systems, wind power generation systems, and biomass power generation systems. All distributed power sources are equipped with a wireless ad hoc network communication module. This module is an embedded wireless device module capable of autonomous networking and communication without relying on fixed infrastructure (such as base stations, routers, or central servers) through automatic node discovery, dynamic connection, and multi-hop relay. The communication protocol of the wireless ad hoc network communication module can be Wi-Fi Mesh, Zigbee, Thread, Bluetooth Mesh, or LoRa Mesh.

[0019] like Figure 4 As shown, the layered architecture of the wireless self-organizing network communication network for distributed power sources includes: The first layer is the application and management layer, which serves as the network's service objects and control brain. It includes the site monitoring system SCADA / EMS and the cloud platform / central control center. The site monitoring system SCADA / EMS, located in the local dispatch center, is responsible for real-time monitoring and advanced applications (such as power distribution, frequency and voltage regulation). The load balancing control module is part of the site monitoring system SCADA / EMS. The cloud platform / central control center performs big data analysis, long-term performance evaluation, and cross-site coordination.

[0020] Applications and management layers communicate with the second-layer architecture via fiber optics, dedicated power wireless networks, or secure VPNs.

[0021] The second layer, the network backbone, provides a stable, high-bandwidth, low-latency data backhaul channel and a network-wide time synchronization source; this layer is the "spine" of the network. It includes a main aggregation gateway and at least one regional aggregation gateway. The main aggregation gateway is deployed in the control center and serves as the network's main exit and root clock source (usually integrating a GPS / BeiDou synchronization module). Regional aggregation gateways are deployed in a distributed manner according to geographical layout (such as different factories or regional power distribution rooms), and they form a fixed mesh backbone network through wired Ethernet or directional wireless microwave.

[0022] The third layer is the network access layer, which enables wireless access for the "last mile" of massive distributed power devices and automatically organizes them into a reliable network. This network adopts a clustered hybrid topology, including multiple clusters, each with a cluster head node. Each cluster head node communicates directly with at least one member node, which is simple, reliable, and has low latency. In this way, clusters form a dynamic mesh through the cluster heads. When a cluster head node cannot directly connect to the backbone gateway, it can be relayed through neighboring cluster heads via multi-hop relay.

[0023] The cluster head node is a device with a suitable location, stable power supply, and strong communication capabilities, such as a large energy storage converter or a communication concentrator; the cluster head node manages members within the cluster, aggregates and compresses data within the cluster, performs local collaborative computing, and acts as a gateway to connect to the backbone layer or other cluster heads.

[0024] The member nodes include photovoltaic inverters, energy storage converters, wind turbine controllers, or electricity meters, etc.

[0025] The fourth layer is the device layer, which serves as the network's sensing and execution terminal. It consists of various distributed power intelligent sensing terminals with built-in or external wireless communication modules. The device layer communicates with the network access layer via its own wireless communication module, typically through a serial port (RS-485 / 232) or Ethernet.

[0026] In this invention, each wireless ad hoc network communication module is connected to the load balancing control module through the edge computing module. In the edge computing module, a double buffering mechanism is used for data processing, with two buffers set up: one for receiving data collected by the underlying nodes in real time, and the other for data processing.

[0027] The load balancing control module includes a load balancing controller, a compensation current adjustment unit, and a load allocation unit. The load balancing controller receives current and voltage information from each distributed power source and the power consumption of the load. It then predicts the future power generation of each distributed power source and adjusts the compensation strategy in advance to ensure that the three-phase load remains balanced when distributed power sources are connected or disconnected. The load allocation unit adjusts the load allocation according to the instructions of the load balancing controller to achieve three-phase load balance. The compensation current adjustment unit adjusts the compensation current according to the instructions of the load balancing controller to reduce the impact on the power grid; the adjustment cycle is 1 minute.

[0028] An automatic compensation load balancing method for an automatic compensation load balancing system for distributed power sources connected to a three-phase unbalanced power grid based on wireless ad hoc networks and edge computing includes the following steps: Step 1: A wireless self-organizing network communication module is installed on each of the distributed power supply and load balancing control modules to automatically form a communication network; the communication distance of the wireless self-organizing network module is 1000 meters and the communication rate is 100Mbps.

[0029] Step 2: When any distributed power source is connected or disconnected, the status information of the distributed power source is quickly transmitted to the automatic compensation load balancing device through a wireless self-organizing network; the status information includes parameters such as the power generation capacity, voltage, and current of the distributed power source, and the data transmission cycle is 1 second.

[0030] Step 2 specifically includes: Step 2.1: Establish a layered architecture for the wireless self-organizing network communication network of distributed power sources; Step 2.1.1: Encryption algorithms are used for data transmission between nodes in the layered architecture of the distributed power source's wireless ad hoc network. The encryption key length is 128 bits, and the encryption period is 1 hour.

[0031] The encryption algorithm employs either symmetric or quantum encryption to ensure communication security. The symmetric encryption algorithm can be AES.

[0032] Quantum encryption, based on the principles of quantum mechanics, offers unconditional security and effectively resists various eavesdropping and attacks. A quantum key distribution device can be integrated into the wireless ad hoc network communication module of an automatic load balancing device and distributed power supply. Before data transmission, the quantum key distribution device encrypts the data using a generated quantum key, and the receiver decrypts it using the corresponding key. Even better, a quantum random number generator can also be integrated into the wireless ad hoc network communication module to generate the random numbers required for encryption, improving the randomness and security of the encryption.

[0033] Step 2.1.2: Each wireless ad hoc network module is equipped with multiple communication channels. The wireless ad hoc network module monitors the signal strength and signal-to-noise ratio of the channels in real time, and then adaptively selects the best communication channel to improve the stability and reliability of communication.

[0034] Step 2.2: Each wireless ad hoc network communication module is connected to the load balancing control module through the edge computing module; Step 2.2.1: The edge computing module employs a double-buffering mechanism for data processing, setting up two buffers: one for receiving data collected from the underlying nodes in real time, and the other for data processing. The buffer size is 1MB, and the data processing cycle is 100ms.

[0035] The edge computing module is responsible for real-time processing and analysis of the collected data. It employs a low-power, high-performance embedded processor to perform preliminary filtering and feature extraction. The wireless ad hoc network communication module performs parallel processing of data filtering and feature extraction, improving data processing speed. The FPGA chip is used for rapid data processing, featuring reconfigurability and parallel processing capabilities.

[0036] Step 2.2.2: The edge computing module makes local decisions on the data according to preset rules, and only uploads the data to the upper-level node when necessary; the local decision rules include load imbalance exceeding 5%, voltage fluctuation exceeding 10%, etc., and the decision cycle is 1 second.

[0037] Step 3: The load balancing control module adjusts the compensation strategy in advance based on the distributed generation forecast information and the grid load conditions to ensure that the three-phase load remains balanced when the distributed generation is connected and disconnected. The compensation strategy includes load distribution adjustment and compensation current adjustment, with an adjustment cycle of 1 minute.

[0038] The power generation forecast information includes solar irradiance forecasts for photovoltaic power plants and wind speed forecasts for wind power generation, with a forecast time range of 1 hour.

[0039] Step 3.1: The compensation current adjustment unit adjusts the compensation current according to the instructions of the load balancer to reduce the impact on the power grid. The compensation current adjustment range is ±5A, and the adjustment cycle is 1 minute.

[0040] like Figure 5 As shown, the compensation current adjustment unit includes an instruction generation layer, a core control layer, and a power execution layer.

[0041] The instruction generation layer includes a detection and calculation module and a reference current generation module. The detection and calculation module extracts harmonic / reactive current. Based on instantaneous reactive power theory, the three-phase current is decomposed into instantaneous active current (ip) and reactive current (iq) through α-β coordinate transformation. The reactive current component directly reflects the system imbalance, and the calculation formula is as follows: Among them, u α Let u be the voltage value in the α coordinate. β The voltage value in the β coordinate; The reference current generation module generates a reference command current 𝑖_𝑟𝑒𝑓; then, the instantaneous active current, reactive current, and reference command current 𝑖_𝑟𝑒𝑓 are sent to the comparator in the core control layer.

[0042] The core control layer includes a comparator, a current controller, a modulation algorithm module, and a drive signal generation module. The comparator compares the reference command current ẋ_ẋ with the actual output current ẋ_ẋ detected by a sensor (such as a Hall current sensor) in real time, generating an instantaneous current error signal ẋ = ẋ_ẋ - ẋ_ẋ.

[0043] The current controller receives the instantaneous current error signal S and calculates a control voltage signal β through a control algorithm, with the goal of making the error S quickly approach zero.

[0044] The control algorithm here is: i) Use a second-order generalized integrator to separate the positive-sequence, negative-sequence, and zero-sequence currents; ii) Compensation strategy: Prioritize compensating negative-sequence components, then process zero-sequence components, and combine hysteresis control or space vector modulation techniques.

[0045] The modulation module converts the continuous-time analog voltage command output by the current controller into a discrete pulse-width modulation signal that can be executed by the power switching devices, and outputs PWM pulses through the drive signal generation module. Common modulation techniques include SPWM or SVPWM.

[0046] The PWM pulse output by the drive signal generation module enters the power actuator, which includes a power converter. The power converter performs level conversion, isolation, and power amplification on the PWM pulse to generate a gate signal that drives switching devices such as IGBTs. The gate signal causes the output module to output a compensation current to the power grid.

[0047] Step 3.2: The load distribution unit adjusts the load distribution according to the instructions of the load balance controller to achieve three-phase load balance. The load distribution adjustment range is ±10%, and the adjustment cycle is 1 minute.

[0048] Alternative Solution 1: An automatic load balancing device for distributed power sources connected to a three-phase unbalanced power grid based on centralized control. 1) The centralized control system includes a central processing unit, a data acquisition module, and an execution module. Its operating principle is the same as that of wireless ad hoc network technology, but all data is centralized in the central processing unit for processing and decision-making.

[0049] 2) Wired communication technology is used to achieve communication between the automatic load balancing device and the distributed power source. Wired communication modules are installed on both the device and the distributed power source. These modules are connected through a wired network to achieve rapid transmission of status information.

[0050] 3) Introduce machine learning algorithms, such as neural network algorithms, into the centralized control system. Collect a large amount of grid load data, distributed power generation output data, etc., and train the neural network. When it is necessary to adjust the compensation strategy, the real-time collected data is input into the trained neural network model, and the model outputs the optimal compensation strategy.

[0051] 4) A dual-buffering mechanism is used for data processing in the centralized control system. Two buffers are set up: one for receiving data collected by the data acquisition module in real time, and the other for data processing. When the data processing in one buffer is completed, the system immediately switches to the other buffer for data processing, and simultaneously uses the processed data to make decisions and execute actions according to preset rules.

[0052] Alternative Solution 2: An automatic load balancing device for distributed power sources connected to a three-phase unbalanced power grid based on distributed control. 1) The distributed control system includes multiple local controllers, data acquisition modules, and execution modules. Its operating principle is the same as that of wireless ad hoc network technology, but each local controller is responsible for the load balancing control of a part of the power grid.

[0053] 2) Wireless mesh network technology is used to achieve communication between the automatic load balancing device and the distributed power source. Wireless mesh network modules are installed on both the device and the distributed power source. These modules can automatically form a communication network. When the distributed power source connects or disconnects, its status information is quickly transmitted to the automatic load balancing device via the wireless mesh network.

[0054] 3) Introduce fuzzy control algorithms into the distributed control system to dynamically adjust the compensation strategy based on changes in grid load and distributed power output, thereby achieving load balance.

[0055] 4) An event-driven mechanism is used for data processing in the distributed control system. When there is a significant change in the grid load or the output of distributed power sources, an event is triggered, and the local controller immediately processes the event, adjusts the compensation strategy, and achieves load balancing.

[0056] The beneficial effects of this invention are as follows: 1. Improved power supply efficiency and reduced equipment losses: By applying an automatic load balancing device, the three-phase imbalance problem of the power grid is effectively addressed, reducing power supply efficiency and equipment losses, and improving the economy and reliability of power grid operation. 2. Enhanced power supply stability and power quality: Addressing the issue of large power grid load fluctuations, this solution improves power supply stability and reduces the impact on user power quality through specialized control strategies and collaborative control mechanisms. 3. Reduced grid losses and power supply costs: By optimizing load allocation and improving power supply reliability, grid losses are reduced, power supply costs are lowered, and the economic benefits of power supply companies are improved. 4. Improved response speed and accuracy of load allocation: Utilizing wireless ad hoc network communication technology and edge computing nodes, fast and accurate load allocation is achieved, adapting to rapidly changing load conditions and reducing the impact of human factors. 5. Simplified communication cabling and reduced costs: The use of wireless ad hoc network technology avoids the complexity and high cost of wired communication cabling, adapting to three-phase unbalanced distribution areas with distributed power supply access. 6. Enhanced data communication security and reliability: By employing symmetric and asymmetric encryption algorithms, the security and reliability of data transmission are ensured, while the adaptive channel selection algorithm improves communication stability. 7. Improve data processing efficiency and real-time performance: Introduce edge computing nodes and a double-buffering mechanism for real-time data processing and analysis, improving data processing efficiency and communication real-time performance. 8. Enhance data processing capabilities: Equipped with dedicated FPGA chips, high-speed caches, and large-capacity storage devices, enhancing the speed of data processing and storage capabilities. 9. Optimize channel selection and adapt to environmental changes: Introduce machine learning algorithms to optimize channel selection, improving communication efficiency while adapting to channel changes in different time periods and environments.

[0057] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several changes and improvements without departing from the overall concept of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. An automatic load balancing system for distributed power generation connected to a three-phase unbalanced power grid, characterized in that: It includes multiple distributed power supply and load balancing control modules, each of which is equipped with a wireless self-organizing network communication module. All distributed power supply and load balancing control modules form a communication network through their respective wireless self-organizing network communication modules. Each wireless ad hoc network communication module is connected to the load balancing control module through the edge computing module. In the edge computing module, a double buffering mechanism is used for data processing, with two buffers set up: one for receiving data collected by the underlying nodes in real time, and the other for data processing. The load balancing control module includes a load balancing controller, a compensation current adjustment unit, and a load distribution unit. The load balancing controller receives current and voltage information from each distributed power source and the power consumption of the load. It then predicts the future power generation of each distributed power source and adjusts the compensation strategy in advance to ensure that the three-phase load remains balanced when distributed power sources are connected or disconnected. The load distribution unit adjusts the load distribution according to the instructions of the load balancing controller to achieve three-phase load balance. The compensation current adjustment unit adjusts the compensation current according to the instructions of the load balancing controller.

2. The automatic compensation load balancing system for distributed power generation connected to a three-phase unbalanced power grid according to claim 1, characterized in that: Distributed power sources include one or more of photovoltaic power generation systems, wind power generation systems, and biomass power generation systems.

3. The automatic compensation load balancing system for distributed power generation connected to a three-phase unbalanced power grid according to claim 1, characterized in that: The layered architecture of the wireless self-organizing network communication network for distributed power sources includes: The first layer is the application and management layer, which includes the SCADA / EMS (Site Monitoring and Control System) and the cloud platform / central control center. The SCADA / EMS is located in the local dispatch center and is responsible for real-time monitoring and advanced applications. The load balancing control module is part of the SCADA / EMS. The cloud platform / central control center performs big data analysis, long-term performance evaluation, and cross-site coordination. The second layer is the network backbone layer, which includes a main aggregation gateway and at least one regional aggregation gateway. The main aggregation gateway is deployed in the control center and serves as the network's main exit and root clock source. The regional aggregation gateways are geographically distributed and form a fixed mesh backbone network through wired Ethernet or directional wireless microwave. The third layer is the network access layer. This network adopts a clustered hybrid topology, which includes multiple clusters. Each cluster includes a cluster head node, and each cluster head node communicates directly with at least one member node. The cluster head node is a large-scale energy storage converter or a communication concentrator; the cluster head node manages members within the cluster, aggregates and compresses data within the cluster, performs local collaborative computing, and acts as a gateway to connect to the backbone layer or other cluster heads; The member nodes include photovoltaic inverters, energy storage converters, wind turbine controllers, or electricity meters; The fourth layer is the device layer, which is the network's sensing and execution terminal. It consists of various distributed power intelligent sensing terminals with built-in or external wireless communication modules.

4. A control method for an automatic compensation load balancing system for distributed power sources connected to a three-phase unbalanced power grid, characterized in that: Includes the following steps: Step 1: A wireless self-organizing network communication module is installed on each of the distributed power supply and load balancing control modules to automatically form a communication network; Step 2: When any distributed power source is connected or disconnected, the status information of the distributed power source is quickly transmitted to the automatic compensation load balancing device through a wireless self-organizing network; the status information includes the power generation, voltage, and current of the distributed power source. Step 3: The load balancing control module adjusts the compensation strategy of the device in advance based on the power generation forecast information of the distributed power source and the grid load situation to ensure that the three-phase load remains balanced when the distributed power source is connected and disconnected; the compensation strategy includes load distribution adjustment and compensation current adjustment.

5. The control method for an automatic load balancing system for distributed power generation connected to a three-phase unbalanced power grid according to claim 4, characterized in that: Step 2 specifically includes: Step 2.1: Establish a layered architecture for the wireless self-organizing network communication network of distributed power sources; Step 2.1.1: Use encryption algorithms to encrypt data transmission between nodes in the layered architecture of the wireless self-organizing network communication network of the distributed power source; Step 2.1.2: Each wireless ad hoc network module is equipped with multiple communication channels. The wireless ad hoc network module monitors the signal strength and signal-to-noise ratio of the channels in real time, and then adaptively selects the best communication channel. Step 2.2: Each wireless ad hoc network communication module is connected to the load balancing control module through the edge computing module; Step 2.2.1: The edge computing module adopts a double buffering mechanism for data processing, setting up two buffers: one for receiving data collected by the underlying nodes in real time, and the other for data processing. Step 2.2.2: The edge computing module makes local decisions on the data according to preset rules, and only uploads the data to the upper-level node when necessary; the local decision rules include load imbalance exceeding 5% and voltage fluctuation exceeding 10%.

6. The control method for an automatic load balancing system for distributed power generation connected to a three-phase unbalanced power grid according to claim 5, characterized in that: In step 2.1.1, the encryption algorithm adopts either a symmetric encryption algorithm or a quantum encryption algorithm. When using a quantum encryption algorithm, before data transmission, the quantum key distribution device uses the generated quantum key to encrypt the data, and the receiver uses the corresponding key to decrypt it. A quantum random number generator can also be integrated into the wireless self-organizing network communication module to generate random numbers required for encryption.

7. The control method for an automatic load balancing system for distributed power generation connected to a three-phase unbalanced power grid according to claim 4, characterized in that: Step 3 includes: Step 3.1: The compensation current adjustment unit adjusts the compensation current according to the instructions of the load balance controller to reduce the impact on the power grid; the compensation current adjustment unit includes an instruction generation layer, a core control layer and a power execution layer; The instruction generation layer includes a detection and calculation module and a reference current generation module. The detection and calculation module extracts harmonic / reactive current. Based on instantaneous reactive power theory, the three-phase current is decomposed into instantaneous active current (ip) and reactive current (iq) through α-β coordinate transformation. The reactive current component directly reflects the system imbalance, and the calculation formula is as follows: Among them, u α Let u be the voltage value in the α coordinate. β The voltage value in the β coordinate; The reference current generation module generates a reference command current 𝑖_𝑟𝑒𝑓; then the instantaneous active current, reactive current and reference command current 𝑖_𝑟𝑒𝑓 are sent to the comparator in the core control layer; The core control layer includes a comparator, a current controller, a modulation algorithm module, and a drive signal generation module; wherein, the comparator compares the reference command current 𝑖_𝑟𝑒𝑓 with the actual output current 𝑖_𝑜𝑢𝑡 detected by the sensor in real time, and generates an instantaneous current error signal 𝑒=𝑖_𝑟𝑒𝑓−𝑖_𝑜𝑢𝑡; The current controller receives the instantaneous current error signal S and calculates a control voltage signal β through a control algorithm, with the goal of making the error S quickly approach zero. The control algorithm is as follows: i) Use a second-order generalized integrator to separate the positive-sequence, negative-sequence, and zero-sequence currents; ii) Compensation strategy: Prioritize compensating negative-sequence components, then process zero-sequence components, combined with hysteresis control or space vector modulation techniques; The modulation module converts the continuous-time analog voltage command output by the current controller into a discrete pulse width modulation signal that can be executed by the power switching device, and outputs PWM pulses through the drive signal generation module; The PWM pulse output by the drive signal generation module enters the power actuator, which includes a power converter. The power converter performs level conversion, isolation and power amplification on the PWM pulse to generate a gate signal to drive switching devices such as IGBTs. The gate signal causes the output module to output a compensation current to the power grid. Step 3.2: The load distribution unit adjusts the load distribution according to the instructions of the load balance controller to achieve the balance of the three-phase load.

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