A control method and system for flexible interconnection technology in low-voltage power distribution areas

Abstract

The method and system of the present invention relate to the technical field of signal devices and include: collecting data of the low-voltage substation area power grid, diagnosing the power grid status based on the power grid data; automatically adjusting the low-voltage substation area power grid to keep the power grid operating normally; real-time displaying the power grid status information and control information; remotely monitoring and controlling the low-voltage substation area power grid based on remote communication technology. A control method for flexible interconnection technology in a low-voltage substation area provided by the present invention effectively improves the power quality in the distribution network by adopting reactive power control, system voltage control, compensation for unbalanced load control, and power grid harmonic filtering control methods. According to information such as the operating conditions of the load and the equipment status, the power flow distribution is regulated to adapt to the random changes in the power of distributed power sources and local loads. Relying on the AC-DC flexible interconnection and fault current limiting functions of the flexible substation, uninterrupted load transfer is achieved, and the present invention achieves better effects in terms of voltage deviation, voltage balance, and voltage fluctuation.

Description

Technical Field

[0001] The present invention relates to the technical field of signal devices, and particularly to a control method and system for flexible interconnection technology in low-voltage power distribution areas. Background Art

[0002] The energy end is facing a structural transformation, with traditional energy developing towards new and clean energy. At the end-user side, there is a high degree of electrification transformation, and the temporal and spatial characteristics of the load are changing. As an important part of the power system, the distribution substation directly affects local economic development and the quality of daily life of users. With the high degree of electrification transformation faced by end-users, the temporal and spatial characteristics of electricity demand have changed. The popularization of electric vehicles, the increase in distributed energy generation systems, and the development of technologies such as smart homes have all had an impact on the power supply load of distribution substations.

[0003] At the current stage, most low-voltage power distribution areas adopt the form of single-transformer and single-line power supply, with low reliability, and the power supply between each substation is independent, lacking unified management and control. The low-voltage power distribution area at the current stage refers to the key node in the power distribution system that is responsible for converting high-voltage electricity into low-voltage electricity and supplying it to end-users. It is usually located in the power supply network of a city or region and is responsible for transmitting electricity to various communities, commercial areas, and households.

[0004] Low-voltage power distribution areas usually adopt the form of single-transformer and single-line power supply. This means that each substation has only one main transformer and one main power supply line to transmit electricity to the corresponding users. This configuration has some defects and challenges to a certain extent.

[0005] First of all, the reliability of low-voltage power distribution areas is low. Due to single-transformer power supply, once the main transformer fails or needs maintenance, the power supply of the entire substation will be interrupted, affecting the normal electricity use of users. This will lead to problems such as production stoppages and life disruptions, bringing inconvenience and economic losses to users.

[0006] Secondly, the power supply between each substation is independent, lacking unified management and control. This means that in the event of a power failure or problem, it is impossible to quickly switch the fault and restore power supply. The independent power supply between substations also leads to fragmentation of the energy system and difficulties in management. For power distribution operators, this makes the monitoring, maintenance, and optimization of the entire power grid more complex.

[0007] In addition, with the improvement of the degree of electrification and the increasing requirements of users for power quality, the temporal and spatial characteristics of the load faced by low-voltage power distribution areas have changed. For example, the widespread popularity of electric vehicles and the increase in distributed energy systems have brought new load challenges to low-voltage power distribution areas. This requires low-voltage power distribution areas to be able to quickly adapt to and respond to load fluctuations at different times and locations to ensure the stability and reliability of power supply. Summary of the Invention

[0008] In view of the above problems, the present invention is proposed.

[0009] Therefore, the technical problems solved by the present invention are as follows: existing low-voltage substation area control methods have low reliability, lack unified management and control, are difficult to adapt to new load characteristics, and cannot quickly adapt to and respond to load fluctuations at different times and locations, and have low efficiency.

[0010] To solve the above technical problems, the present invention provides the following technical solution: a control method for flexible interconnection technology in a low-voltage substation area, including: collecting data of the low-voltage substation area power grid, diagnosing the power grid state based on the grid data, automatically adjusting the low-voltage substation area power grid to keep the power grid operating normally, displaying the grid state information and control information in real time, and remotely monitoring and controlling the low-voltage substation area power grid based on remote communication technology.

[0011] As a preferred scheme of a control method for flexible interconnection technology in a low-voltage substation area according to the present invention, wherein: the collecting data of the low-voltage substation area power grid includes collecting the current, voltage and power of the low-voltage substation area power grid, monitoring the operating conditions of the low-voltage flexible interconnection device, collecting the position state, the access state of the control output loop switch and the state information;

[0012] When the loop switch changes its position, the controller stores the event and sends a position change signal to the master station or actively reports it when the master station queries.

[0013] As a preferred scheme of a control method for flexible interconnection technology in a low-voltage substation area according to the present invention, wherein: the diagnosing the power grid state based on the grid data includes analyzing and processing the collected data to diagnose the power grid state;

[0014] If abnormal conditions occur in the power grid, including power failures, overloads, short circuits, phase sequence disorders, voltage fluctuations and frequency offsets, the controller stores the abnormal conditions and sends a position change signal to the master station or actively reports it when the master station queries;

[0015] If the abnormal condition is a power failure, using the flexible interconnection technology, quickly connect the nearby standby power supply or energy storage device, temporarily supply power, and use the cloud data prediction technology to detect possible power failures in advance and dispatch resources;

[0016] If the abnormal condition is an overload, through the low-voltage flexible interconnection controller, automatically adjust the load distribution, transfer part of the power to the line without abnormal conditions, use the Internet of Things sensing terminal to monitor the real-time load and predict the future increasing load, and make adjustments in advance;

[0017] If the abnormal condition is a short circuit, using the flexible interconnection technology, quickly isolate the short-circuit area and reconnect the area without abnormal conditions to the main network;

[0018] If the abnormal situation is phase sequence disorder, use the primary fusion intelligent circuit breaker and the secondary fusion intelligent circuit breaker once. When phase sequence disorder is detected, quickly disconnect to avoid equipment damage. Utilize the communication function of the flexible interconnection device in the substation area to monitor the phase sequence of the power grid in real time. Once an abnormality is detected, perform correction;

[0019] If the abnormal situation is voltage fluctuation, utilize energy storage equipment to supply power to the power grid and suppress voltage fluctuation. Use the Internet of Things sensing terminal to predict voltage fluctuation events and perform voltage regulation in advance through flexible interconnection technology;

[0020] If the abnormal situation is frequency deviation, utilize the interconnection of substations in the area with flexible DC technology to automatically adjust the power supply frequency to keep it consistent with the standard frequency. Combine with the technical architecture of the distribution Internet of Things to monitor frequency deviation in real time and perform dynamic adjustment according to the predicted data;

[0021] If there is no abnormal situation in the power grid, the controller responds to the call measurement, regularly or randomly sends the power grid status information to the intelligent fusion terminal in the substation area, obtains the relevant operation data on the intelligent fusion terminal side of the substation area, communicates with the flexible interconnection device in the substation area, and communicates through optical fiber to respond to the demand for rapid control on the local side;

[0022] Among them, the controller supports communication with the intelligent fusion terminal in the substation area and adopts a lightweight communication protocol.

[0023] As a preferred solution of a control method for the flexible interconnection technology of a low-voltage substation area described in the present invention, wherein: automatically adjusting the low-voltage substation area power grid to keep the power grid operating normally includes the controller performing parameter setting and query through the master station, the intelligent fusion terminal in the substation area or the local operation and maintenance tool, setting the controller and querying the communication address, configuration parameters, and communication parameters, automatically judging the generation or recovery of events according to the event attributes set by the master station or the intelligent fusion terminal in the substation area, and having a local status indication;

[0024] Among them, the communication parameters include wireless remote communication parameters, Ethernet remote communication parameters, Ethernet local communication parameters, and local maintenance port communication parameters;

[0025] Among them, the data collected by the controller setting includes point table information, collection frequency, operation control strategy, and protection parameter setting values;

[0026] Among them, the events include critical events, important events, and ordinary events;

[0027] If the event is identified as a critical event, the event causes an instantaneous interruption of the power grid or equipment damage, and the parameter configuration reaches the reporting threshold. The parameters recorded by the controller include the event type, occurrence time, and associated data information, and report the parameter status to the master station for subsequent query or analysis;

[0028] When the critical event is determined to be a communication interruption, use the local maintenance port for emergency communication and perform emergency recovery through the intelligent integrated terminal in the power distribution area;

[0029] When the critical event is determined to be equipment damage, notify the maintenance personnel for emergency repair through Ethernet or wireless remote communication, and use the intelligent integrated terminal in the power distribution area for remote monitoring of the equipment status;

[0030] If the event is identified as an important event, the event affects the normal operation of the power grid but does not cause the power grid to interrupt, and the parameter configuration does not reach the reporting threshold. The controller records the event and reports a summary once a day. If it repeats more than 5 times within 1 hour, the event is marked as a critical event, and the controller reports the parameter status for subsequent query or analysis;

[0031] When the important event is determined to be unstable operation of the power grid, the controller collects the frequency and operation control strategy according to the point table information, automatically adjusts the load, or manually adjusts the frequency through the intelligent integrated terminal in the power distribution area or the local operation and maintenance tool;

[0032] If the event is identified as an ordinary event, the event has no impact on the operation of the power grid, and the parameter configuration does not reach the reporting threshold. The controller records the event and reports a summary once a day. If it repeats more than 5 times within 1 hour, the event is marked as a critical event, and the controller reports the parameter status for subsequent query or analysis;

[0033] When the ordinary event is determined to be a small fluctuation in the operation of the power grid or a minor equipment failure, the controller attempts to re - establish the connection. If the re - connection fails, start the secure Bluetooth or use the local maintenance port for communication to notify the maintenance personnel. The controller attempts self - recovery. If it fails, start the backup system; perform software upgrade or roll back to the previous stable version through the intelligent integrated terminal in the power distribution area or the local operation and maintenance tool;

[0034] The parameters recorded by the controller include the event type, occurrence time, and associated data information, and report the parameter status to the master station for subsequent query or analysis;

[0035] If the parameter configuration does not reach the reporting threshold when the event occurs or is recovered, the controller does not record and report the event, but sends an alarm, notifies the maintenance personnel, or performs automatic adjustment, and records the alarm information to provide data for subsequent query and analysis;

[0036] Among them, the local status includes indicating the terminal operation, data transmission, and alarm, and has a secure Bluetooth and an Ethernet local maintenance interface. Set the terminal parameters and settings through the maintenance interface and perform software upgrade.

[0037] As a preferred solution of a control method for a flexible interconnection technology in a low-voltage substation area of the present invention, wherein: the real-time display of grid status information and control information includes connecting a centralized measurement and control terminal and DC equipment on a DC bus through a micro-power wireless and carrier dual-mode communication network under a flexible DC interconnection device substation area;

[0038] Among them, the head-end module is installed on the centralized measurement and control terminal, and the tail-end module is installed on the DC equipment on the DC bus.

[0039] As a preferred solution of a control method for a flexible interconnection technology in a low-voltage substation area of the present invention, wherein: the real-time display of grid status information and control information includes that through a dual-mode communication network architecture, the head-end node and the tail-end node use wireless and power line carrier as transmission media to form a mesh network structure centered on the head-end node;

[0040] Among them, the micro-power wireless and carrier dual-mode communication network consists of a head-end node and a tail-end node, and one head-end node and multiple tail-end nodes form a mesh network centered on the head-end node.

[0041] As a preferred solution of a control method for a flexible interconnection technology in a low-voltage substation area of the present invention, wherein: the remote monitoring and control of the low-voltage substation area grid based on remote communication technology includes predicting data through a controller and an energy management system to specify an optimized scheduling instruction for the interconnection system, realizing real-time monitoring and control of the operation status of the substation area interconnection system, and at the same time carrying out intelligent transformation of the medium and low-voltage Internet of Things in combination with the distribution Internet of Things technology architecture based on the flexible DC technology of the substation area interconnection, replacing the low-voltage main incoming switch and feeder switch in the substation area of the system, deploying primary integrated intelligent circuit breakers and secondary integrated intelligent circuit breakers, sensing terminals, and environmental monitoring Internet of Things end devices, and entering the cloud master station system through wireless communication to realize full perception of the operation status of the substation area.

[0042] Another object of the present invention is to provide a control system for a flexible interconnection technology in a low-voltage substation area, which can improve the reliability, economy and safety of the power grid by real-time monitoring, remote control and automatic adjustment of the low-voltage substation area grid.

[0043] As a preferred solution of a low-voltage substation area flexible interconnection technology control system according to the present invention, it includes an initialization module, a power grid diagnosis module, a power grid control module, an information display module, and a power grid monitoring and control module; the initialization module is used to collect data, position status, control output loop switch access status, and status information of the low-voltage substation area power grid, and monitor the operating conditions of the low-voltage flexible interconnection device; the power grid diagnosis module is used to analyze and process data, diagnose the power grid status, and feedback power grid anomalies; the power grid control module is used to automatically adjust the low-voltage substation area power grid to keep the power grid operating in a normal state; the information display module is used to display power grid status information and control information; the power grid monitoring and control is used to remotely monitor and control the low-voltage substation area power grid through remote communication technology.

[0044] A computer device includes a memory and a processor, the memory stores a computer program, and is characterized in that when the processor executes the computer program, it realizes the steps of a control method for a low-voltage substation area flexible interconnection technology.

[0045] A computer-readable storage medium stores a computer program, and is characterized in that when the computer program is executed by a processor, it realizes the steps of a control method for a low-voltage substation area flexible interconnection technology.

[0046] The beneficial effects of the present invention: The control method for a low-voltage substation area flexible interconnection technology provided by the present invention reduces the system voltage deviation, improves voltage imbalance, suppresses system voltage fluctuations, and filters out power grid harmonics by adopting reactive power control, system voltage control, compensation for unbalanced loads control, and power grid harmonic filtering control methods, effectively improving the power quality in the distribution network. According to information such as the operating conditions of loads and the status of equipment, it flexibly and dynamically regulates the power flow distribution to adapt to the random changes of distributed power sources and local load powers. Secondly, relying on the AC-DC flexible interconnection and fault current limiting functions of the flexible substation, it can also achieve uninterrupted load transfer, limit the current during a short circuit in the distribution network, and isolate faults in case of faults, further improving the power supply capacity of the distribution network. The present invention achieves better effects in terms of voltage deviation, voltage balance, and voltage fluctuation. Description of the Drawings

[0047] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for description in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts. Among them:

[0048] Figure 1 It is the overall flowchart of a control method for a low-voltage substation area flexible interconnection technology provided by the first embodiment of the present invention.

[0049] Figure 2 Schematic diagram of a centralized flexible interconnection system with a common DC bus for a low-voltage substation area flexible interconnection technology control method provided in the first embodiment of the present invention.

[0050] Figure 3 Schematic diagram of a decentralized flexible interconnection system with segmented DC buses for a low-voltage substation area flexible interconnection technology control method provided in the first embodiment of the present invention.

[0051] Figure 4 Schematic diagram of a low-voltage substation area flexible interconnection control system for a low-voltage substation area flexible interconnection technology control method provided in the first embodiment of the present invention.

[0052] Figure 5 Schematic diagram of multi-level AC-DC coordination of low-voltage substation area flexible interconnection for a low-voltage substation area flexible interconnection technology control method provided in the first embodiment of the present invention.

[0053] Figure 6 Schematic diagram of low-voltage substation area flexible interconnection between grid and load for a low-voltage substation area flexible interconnection technology control method provided in the first embodiment of the present invention.

[0054] Figure 7 Schematic diagram of low-voltage substation area flexible interconnection between power source and load for a low-voltage substation area flexible interconnection technology control method provided in the first embodiment of the present invention.

[0055] Figure 8 Overall flowchart of a low-voltage substation area flexible interconnection technology control system provided in the third embodiment of the present invention. Detailed implementation manners

[0056] To make the above objects, features and advantages of the present invention more obvious and understandable, the following will describe the detailed implementation manners of the present invention with reference to the accompanying drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0057] In the following description, many specific details are set forth to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0058] Second, the "one embodiment" or "embodiment" mentioned herein refers to specific features, structures or characteristics that may be included in at least one implementation manner of the present invention. The appearances of "in one embodiment" in different places in this specification do not all refer to the same embodiment, nor are they separate or alternative embodiments that exclude each other with other embodiments.

[0059] The present invention will be described in detail with reference to the schematic diagrams. When describing the embodiments of the present invention in detail, for the convenience of explanation, the cross-sectional views showing the device structure will be enlarged locally in a non-general proportion, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention herein. In addition, in actual production, three-dimensional spatial dimensions including length, width and depth should be included.

[0060] At the same time, in the description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "upper, lower, inner and outer" is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0061] Unless otherwise clearly defined and limited in the present invention, the terms "installed, connected, connected" should be understood in a broad sense. For example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, and can also be indirectly connected through an intermediate medium, or can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0062] Embodiment 1

[0063] Referring to Figure 1-7 , for an embodiment of the present invention, a control method for flexible interconnection technology in a low-voltage power distribution area is provided, including:

[0064] S1: Collect data of the low-voltage power distribution area power grid.

[0065] Furthermore, collecting data of the low-voltage power distribution area power grid includes collecting the current, voltage and power of the low-voltage power distribution area power grid, monitoring the operating conditions of the low-voltage flexible interconnection device, collecting the position state, the access state of the control output loop switch and the status information; when the loop switch changes its position, the controller stores the event and sends a position change signal to the master station or actively reports it when queried by the master station.

[0066] It should be noted that the low-voltage flexible interconnection in-situ controller has a voltage acquisition function, measuring voltage, current, power, power factor, etc. It monitors the operating conditions of the low-voltage flexible interconnection device in real time. The controller collects position status, control output loop switch access status and other status information in real time. When a change occurs, it should store the event and send the change signal to the master station when the master station queries for the last time or report it actively.

[0067] S2: Analyze and process the collected data to diagnose the power grid status;

[0068] Furthermore, analyze and process the collected data to diagnose the power grid status;

[0069] If abnormal situations occur in the power grid, including power failures, overloads, short circuits, phase sequence disorders, voltage fluctuations and frequency offsets, the controller stores the abnormal situations and sends the change signal to the master station when the master station queries or reports it actively;

[0070] If the abnormal situation is a power failure, use the flexible interconnection technology to quickly connect the nearby standby power supply or energy storage device to supply power temporarily, and use the cloud data prediction technology to detect possible power failures in advance and dispatch resources;

[0071] If the abnormal situation is an overload, through the low-voltage flexible interconnection controller, automatically adjust the load distribution, transfer part of the power to the lines without abnormal situations, use the Internet of Things sensing terminals to monitor the real-time load and predict the future increasing load, and make adjustments in advance;

[0072] If the abnormal situation is a short circuit, use the flexible interconnection technology to quickly isolate the short-circuit area and reconnect the area without abnormal situations to the main grid;

[0073] If the abnormal situation is a phase sequence disorder, use the primary fusion intelligent circuit breaker and the secondary fusion intelligent circuit breaker. When a phase sequence disorder is detected, quickly disconnect to avoid equipment damage, and use the communication function of the distribution area flexible interconnection device to monitor the phase sequence of the power grid in real time. Once an abnormality is detected, make corrections;

[0074] If the abnormal situation is a voltage fluctuation, use the energy storage device to supply power to the power grid to suppress the voltage fluctuation, use the Internet of Things sensing terminals to predict the voltage fluctuation event, and perform voltage regulation in advance through the flexible interconnection technology;

[0075] If the abnormal situation is a frequency offset, use the flexible DC technology for interconnection of distribution areas to automatically adjust the power supply frequency to keep it consistent with the standard frequency, combine with the power distribution Internet of Things technology architecture, monitor the frequency offset in real time, and make dynamic adjustments according to the predicted data;

[0076] If there is no abnormality in the power grid, the controller responds to the call measurement, sends the power grid status information to the intelligent integrated terminal of the substation area regularly or randomly, obtains the relevant operation data on the side of the intelligent integrated terminal of the substation area, communicates with the flexible interconnection device of the substation area, and communicates through optical fiber to respond to the demand for rapid control on the local side;

[0077] Among them, the controller supports communicating with the intelligent integrated terminal of the substation area and adopts a lightweight communication protocol.

[0078] It should be noted that the controller supports communicating with the intelligent integrated terminal of the substation area and preferably adopts a lightweight communication protocol, including responding to the call measurement; or sending relevant information to the intelligent integrated terminal of the substation area regularly or randomly; obtaining the relevant operation data on the side of the intelligent integrated terminal of the substation area; the controller supports communicating with other flexible interconnection devices of the substation area and communicates through optical fiber to respond to the demand for rapid control on the local side.

[0079] S3: Automatically adjust the low-voltage substation area power grid to keep the power grid operating in a normal state.

[0080] Furthermore, the controller performs parameter setting and query through the master station, the intelligent integrated terminal of the substation area or the local operation and maintenance tool, sets the controller and queries the communication address, configuration parameters, and communication parameters, automatically judges the generation or recovery of events according to the event attributes set by the master station or the intelligent integrated terminal of the substation area, and has a local status indication;

[0081] Among them, the communication parameters include wireless remote communication parameters, Ethernet remote communication parameters, Ethernet local communication parameters, and local maintenance port communication parameters;

[0082] Among them, the data collected by the controller includes point table information, collection frequency, operation control strategy, and protection parameter setting values;

[0083] Among them, the events include critical events, important events, and ordinary events;

[0084] If the event is identified as a critical event, the event causes an instantaneous interruption of the power grid or equipment damage, and the parameter configuration reaches the reporting threshold. The parameters recorded by the controller include the event type, occurrence time, and associated data information, and report the parameter status to the master station for subsequent query or analysis;

[0085] When the critical event is determined to be a communication interruption, use the local maintenance port for emergency communication and perform emergency recovery through the intelligent integrated terminal of the substation area;

[0086] When the critical event is determined to be equipment damage, notify the maintenance personnel for emergency repair through Ethernet or wireless remote communication, and use the intelligent integrated terminal of the substation area for remote monitoring of the equipment status;

[0087] If the event is identified as an important event, the event affects the normal operation of the power grid but does not cause the power grid to interrupt, and the parameter configuration does not reach the reporting threshold value, the controller records the event and reports a summary once a day. If it repeats more than 5 times within 1 hour, the event is marked as a critical event, and the controller reports the parameter status for subsequent query or analysis;

[0088] When the important event is determined to be unstable power grid operation, the controller collects the frequency and operation control strategy according to the point table information, automatically adjusts the load, or manually adjusts the frequency through the intelligent fusion terminal of the substation area or the local operation and maintenance tool;

[0089] If the event is identified as an ordinary event, the event has no impact on the operation of the power grid, and the parameter configuration does not reach the reporting threshold value, the controller records the event and reports a summary once a day. If it repeats more than 5 times within 1 hour, the event is marked as a critical event, and the controller reports the parameter status for subsequent query or analysis;

[0090] When the ordinary event is determined to be a small fluctuation in the power grid operation or a minor equipment failure, the controller attempts to re - establish the connection. If it cannot reconnect, it activates the secure Bluetooth or uses the local maintenance port for communication to notify the maintenance personnel. The controller attempts self - recovery. If it fails, it starts the backup system; software upgrade or rollback to the previous stable version is performed through the intelligent fusion terminal of the substation area or the local operation and maintenance tool;

[0091] The parameters recorded by the controller include the event type, occurrence time, and associated data information, and report the parameter status to the master station for subsequent query or analysis;

[0092] If the parameter configuration does not reach the reporting threshold value when the event occurs or recovers, the controller does not record or report the event, but sends an alarm, notifies the maintenance personnel, or performs automatic adjustment, and at the same time records the alarm information to provide data for subsequent query and analysis;

[0093] Among them, the local status includes indicating the terminal operation, data transmission, and alarm, and has a secure Bluetooth and an Ethernet local maintenance interface. The terminal parameters and setting values are set through the maintenance interface, and software upgrade is performed. It should be noted that parameter setting and query. The controller supports parameter setting and query by the master station, the intelligent fusion terminal of the substation area, or the local operation and maintenance tool. Communication addresses, configuration parameters, communication parameters, etc. can be set and queried for the controller. The communication parameters include wireless remote communication parameters, Ethernet remote communication parameters, Ethernet local communication parameters, and local maintenance port communication parameters. Information such as the acquisition data point table information, acquisition frequency, operation control strategy, and protection parameter setting values can be set for the controller.

[0094] It should also be noted that for event reporting, the controller automatically determines the generation or recovery of an event based on the event attributes set by the master station or the intelligent fusion terminal in the substation area. When an event is generated or recovered, it decides whether to report according to the parameter configuration, and at the same time records the reporting status. The content of each record includes the event type, the occurrence time, and relevant associated data information.

[0095] Furthermore, for local functions, it should have local status indicators to indicate the working status such as terminal operation, data transmission, and alarm. It should have local maintenance interfaces such as secure Bluetooth and Ethernet to set terminal parameters, fixed values, and perform software upgrades through the maintenance interfaces.

[0096] S4: Real-time display of power grid status information and control information.

[0097] Furthermore, under the flexible DC interconnected device substation area, the centralized measurement and control terminal is connected to the DC equipment on the DC bus through a micro-power wireless and carrier dual-mode communication network; among them, the head-end module is installed on the centralized measurement and control terminal, and the tail-end module is installed on the DC equipment on the DC bus.

[0098] It should be noted that in the micro-power wireless + carrier dual-mode communication mode, under the flexible DC interconnected device substation area, the centralized measurement and control terminal and the DC equipment on the DC bus can be connected through a micro-power wireless + carrier dual-mode communication network: the head-end module is installed on the centralized measurement and control terminal, and the tail-end module is installed on the DC equipment on the DC bus.

[0099] It should also be noted that for the dual-mode communication network architecture, the micro-power wireless + carrier dual-mode communication network consists of a head-end node (HD) and a tail-end node (ED). One head-end node and multiple tail-end nodes form a mesh network centered on the head-end node. The head-end node is the central node of the network, supporting HPLC and 470MHz-RF communication, responsible for network construction, conflict avoidance, IP address allocation, network maintenance and management, responsible for access management, routing maintenance and resource allocation of the tail-end nodes, and realizing data transmission between each node in the network and the centralized measurement and control terminal. The tail-end node is a subordinate node of the network, supporting HPLC and communication, participating in network construction, maintenance and management, responsible for data transmission of this node and data forwarding of its sub-nodes. The communication network is centered on the head-end node, and the head-end node and the tail-end node use wireless and power line carrier as transmission media to form a mesh network structure centered on the head-end node.

[0100] S5: Remote monitoring and control of the low-voltage substation area power grid through remote communication technology.

[0101] Furthermore, the controller and the energy management system can specify optimized scheduling instructions for the interconnected system based on the predicted data to achieve real-time monitoring and control of the operating status of the interconnected system in the substation area. The interconnection of substations in the area based on flexible DC technology can carry out intelligent transformation of medium and low voltage Internet of Things in combination with the power distribution Internet of Things technology architecture of "cloud, pipe, edge, and terminal". The low-voltage main incoming switch and feeder switch in the original system need to be replaced, and a primary integrated intelligent circuit breaker, a secondary integrated intelligent circuit breaker, sensing terminals, environmental monitoring and other Internet of Things terminal devices are deployed. After wireless communication, they enter the cloud master station system to achieve full perception of the operating status of the substation area, functions such as integration of operation and distribution, and optimization and improvement of power quality.

[0102] It should be noted that when applied to the interconnection at the low-voltage end, the power quality of the feeder is improved.

[0103] When the flexible multi-state switch is connected to the low-voltage end of the distribution network, it can achieve multiple control objectives such as coordinated consumption of renewable energy, improvement of power quality, and balancing of feeder load, forming a comprehensive control means for the distribution network.

[0104] By adopting methods such as reactive power control, system voltage control, compensation for unbalanced load control, and filtering of grid harmonics, the system voltage deviation is reduced, voltage imbalance is improved, system voltage fluctuation is suppressed, and grid harmonics are filtered, effectively improving the power quality in the distribution network.

[0105] According to information such as the operating conditions of the load and the status of equipment, the power flow distribution is flexibly and dynamically regulated to adapt to the random changes in the power of distributed power sources and local loads. At the same time, the flexible multi-state switch can also perform rapid power flow reversal and feeder balancing control according to the actual situation on site.

[0106] It should also be noted that when interconnecting feeders with different voltages, mutual support between different voltage levels is achieved.

[0107] The flexible interconnection of feeders with different voltages can also be called a flexible substation, which is an electronically powered product based on the primary equipment of a conventional substation. It has medium / low voltage, AC / DC multi-terminal interface connections, can flexibly handle the two-way power flow problem caused by the grid connection of distributed power sources, realize the flexible access and efficient utilization of distributed energy, improve the reliability of the distribution network, and make full use of renewable energy.

[0108] Relying on the AC / DC flexible interconnection and fault current limiting functions of the flexible substation, it is also possible to achieve uninterrupted load transfer, limit the current during a short circuit in the distribution network, and isolate faults in case of faults, further improving the power supply capacity of the distribution network.

[0109] When a fault occurs in the distribution network, rapid blocking through the flexible multi-state switch can effectively limit the fault current, achieve fault isolation in different zones, and keep the short-circuit capacity of the original system unchanged. By simply adjusting the outlet voltage of the flexible multi-state switch, the operation of the distribution network can be restored as soon as possible.

[0110] Embodiment 2

[0111] An embodiment of the present invention provides a control method for flexible interconnection technology in low-voltage distribution areas. To verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0112] Select two sets of distribution system configurations for testing, divide them into two groups for experiments. One group is a traditional low-voltage distribution system, and the other set uses the present invention to perform the same operations.

[0113] As shown in Table 1, in this experiment, the traditional low-voltage distribution system represents a conventional low-voltage distribution system using a single transformer and single-line power supply. The experiment will monitor parameters such as voltage deviation, voltage unbalance, voltage fluctuation, and harmonic distortion to evaluate the power quality performance of the traditional system.

[0114] On the other hand, the present invention includes flexible multi-state switches and flexible interconnection technology. The experiment will monitor power quality parameters and also monitor the power flow distribution within the system. By using methods such as reactive power control, system voltage control, compensating unbalanced loads, and filtering harmonics, the new technology aims to improve power quality and achieve flexible control of power flow distribution.

[0115] The experiment will record the power quality problems and limitations observed in the traditional system, as well as the power quality improvement and flexibility of power flow control obtained by using the present invention. Data analysis will involve comparing the performance of traditional technologies with the improvements of the present invention.

[0116] Table 1 Comparison chart of experimental results

[0117]

[0118]

[0119] In the comparison data, the power quality parameters under traditional technologies include voltage deviation, voltage unbalance, voltage fluctuation, and harmonic distortion. In contrast, these power quality parameters using the present invention have all shown improvements.

[0120] For example, the voltage deviation is reduced from 2.5% under the traditional technology to 1.0% under the new technology; the voltage unbalance is reduced from 3.2% under the traditional technology to 1.5% under the new technology; the voltage fluctuation is reduced from 4.0% under the traditional technology to 1.7% under the new technology; and the harmonic distortion is reduced from 7.8% under the traditional technology to 3.2% under the new technology.

[0121] In addition, the present invention also has the flexibility of power flow distribution control. Compared with the limited control ability of the traditional technology, the new technology can more flexibly adjust the power flow distribution to adapt to different requirements and conditions.

[0122] In summary, the invention of our side is an optimal solution in terms of time consumption.

[0123] Embodiment 3

[0124] Referring to Figure 8 , an embodiment of the present invention provides a load balancing system for a computing platform based on a particle swarm genetic algorithm, including: an initialization module, a power grid diagnosis module, a power grid control module, an information display module, and a power grid monitoring and control module.

[0125] Among them, the initialization module is used to collect data, position status, control output loop switch access status, and status information of the low-voltage substation area power grid, and monitor the operating conditions of the low-voltage flexible interconnection device. The power grid diagnosis module is used to analyze and process data, diagnose the power grid status, and feedback power grid anomalies. The power grid control module is used to automatically adjust the low-voltage substation area power grid to keep the power grid operating in a normal state. The information display module is used to display power grid status information and control information. The power grid monitoring and control is used to remotely monitor and control the low-voltage substation area power grid through remote communication technology.

[0126] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0127] The logic and / or steps represented in the flowchart or otherwise described herein can, for example, be considered a definitional sequence of executable instructions for implementing logical functions, which can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device. As used in this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with the instruction execution system, apparatus, or device.

[0128] More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection (electronic device) having one or more wirings, a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which a program can be printed, as the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or other suitable processing as necessary, and then stored in a computer memory.

[0129] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc. It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

[0130] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A control method for flexible interconnection technology in low-voltage distribution areas, characterized in that, it includes: Collect data of the low-voltage distribution area power grid, and diagnose the power grid status based on the grid data; Automatically adjust the low-voltage distribution area power grid to keep the power grid operating normally; Real-time display of power grid status information and control information; Based on remote communication technology, remotely monitor and control the low-voltage distribution area power grid; The diagnosing the power grid status based on grid data includes analyzing and processing the collected data to diagnose the power grid status; If abnormal conditions occur in the power grid, including power failures, overloads, short circuits, phase sequence disorders, voltage fluctuations, and frequency offsets, the controller stores the abnormal conditions and sends a change signal to the master station or actively reports when queried by the master station; If the abnormal condition is a power failure, use flexible interconnection technology to quickly connect nearby backup power sources or energy storage devices to temporarily supply power, and use cloud data prediction technology to detect possible power failures in advance and dispatch resources; If the abnormal condition is an overload, through the low-voltage flexible interconnection controller, automatically adjust the load distribution, transfer part of the power to the lines without abnormal conditions, use the Internet of Things sensing terminal to monitor the real-time load and predict the future increasing load, and make adjustments in advance; If the abnormal condition is a short circuit, use flexible interconnection technology to quickly isolate the short-circuit area and reconnect the area without abnormal conditions to the main grid; If the abnormal condition is a phase sequence disorder, use a primary fusion intelligent circuit breaker and a secondary fusion intelligent circuit breaker. When a phase sequence disorder is detected, quickly disconnect to avoid equipment damage. Use the communication function of the distribution area flexible interconnection device to monitor the phase sequence of the power grid in real time. Once an abnormality is detected, correct it; If the abnormal condition is voltage fluctuation, use energy storage devices to supply power to the power grid to suppress voltage fluctuations, use the Internet of Things sensing terminal to predict voltage fluctuation events, and perform voltage regulation in advance through flexible interconnection technology; If the abnormal condition is frequency offset, use the flexible DC technology for interconnection of distribution areas to automatically adjust the power supply frequency to keep it consistent with the standard frequency. Combine with the technical architecture of the distribution Internet of Things to monitor the frequency offset in real time and make dynamic adjustments according to the prediction data; If no abnormal conditions occur in the power grid, the controller responds to the call measurement, regularly or randomly sends power grid status information to the distribution area intelligent fusion terminal, obtains relevant operation data on the distribution area intelligent fusion terminal side, communicates with the distribution area flexible interconnection device, and communicates through optical fiber to respond to the requirements of rapid control on the local side; Among them, the controller supports communication with the distribution area intelligent fusion terminal and uses a lightweight communication protocol.

2. A control method for flexible interconnection technology in low-voltage distribution areas according to claim 1, characterized in that: The collecting the data of the low-voltage distribution area power grid includes collecting the current, voltage and power of the low-voltage distribution area power grid, monitoring the operating conditions of the low-voltage flexible interconnection device, collecting position status, control output loop switch access status and status information; When the loop switch changes its position, the controller stores the event and sends a change signal to the master station or actively reports when queried by the master station.

3. A control method for flexible interconnection technology in low-voltage distribution areas according to claim 2, characterized in that: The automatic adjustment of the low-voltage substation power grid to maintain normal grid operation includes the controller setting and querying parameters through the master station, the substation intelligent fusion terminal or the local operation and maintenance tool, setting the controller and querying the communication address, configuration parameters, and communication parameters, automatically judging the generation or recovery of events according to the event attributes set by the master station or the substation intelligent fusion terminal, and having local status indication; Among them, the communication parameters include wireless remote communication parameters, Ethernet remote communication parameters, Ethernet local communication parameters, and local maintenance port communication parameters; Among them, the controller setting of the collected data includes point table information, collection frequency, operation control strategy, and protection parameter setting value; Among them, the events include critical events, important events, and ordinary events; If the event is identified as a critical event, the event causes an instantaneous interruption of the power grid or equipment damage, and the parameter configuration reaches the reporting threshold value. The parameters recorded by the controller include the event type, occurrence time, and associated data information, and the parameter status is reported to the master station for subsequent query or analysis; When the critical event is determined to be a communication interruption, the local maintenance port is used for emergency communication, and emergency recovery is performed through the substation intelligent fusion terminal; When the critical event is determined to be equipment damage, the maintenance personnel are notified for emergency repair through Ethernet or wireless remote communication, and the remote monitoring of the equipment status is performed using the substation intelligent fusion terminal; If the event is identified as an important event, the event affects the normal operation of the power grid and does not cause a power grid interruption, and the parameter configuration does not reach the reporting threshold value. The controller records the event and reports a summary once a day. If it repeats more than 5 times within 1 hour, the event is marked as a critical event, and the controller reports the parameter status for subsequent query or analysis; When the important event is determined to be unstable power grid operation, the controller automatically adjusts the load according to the point table information, collection frequency, and operation control strategy, or manually adjusts the frequency through the substation intelligent fusion terminal or the local operation and maintenance tool; If the event is identified as an ordinary event, the event has no impact on the power grid operation, and the parameter configuration does not reach the reporting threshold value. The controller records the event and reports a summary once a day. If it repeats more than 5 times within 1 hour, the event is marked as a critical event, and the controller reports the parameter status for subsequent query or analysis; When the ordinary event is determined to be a small power grid fluctuation or a small equipment fault, the controller attempts to re-establish the connection. If the connection cannot be re-established, the secure Bluetooth is started or the local maintenance port communication is used to notify the maintenance personnel. The controller attempts to self-recover. If it fails, the backup system is started; software upgrade or rollback to the previous stable version is performed through the substation intelligent fusion terminal or the local operation and maintenance tool; The parameters recorded by the controller include the event type, occurrence time, and associated data information, and the parameter status is reported to the master station for subsequent query or analysis; If the parameter configuration does not reach the reporting threshold value when the event is generated or recovered, the controller does not record and report the event, and sends an alarm, notifies the maintenance personnel or performs automatic adjustment, and at the same time records the alarm information to provide data for subsequent query and analysis; Among them, the local status includes indicating terminal operation, data transmission, and alarms, and has a secure Bluetooth and Ethernet local maintenance interface. Terminal parameters and settings are set through the maintenance interface, and software upgrades are performed.

4. A control method for a flexible interconnection technology in a low-voltage power distribution area as described in claim 3, characterized in that: The real-time display of grid status information and control information includes, under the flexible DC interconnection device substation area, connecting a centralized measurement and control terminal and DC equipment on the DC bus through a micro-power wireless and carrier dual-mode communication network; Among them, the head-end module is installed on the centralized measurement and control terminal, and the tail-end module is installed on the DC equipment on the DC bus.

5. A control method for a flexible interconnection technology in a low-voltage power distribution area as described in claim 4, characterized in that: The real-time display of grid status information and control information includes, through the dual-mode communication network architecture, using wireless and power line carrier as the transmission medium for the head-end node and the tail-end node to form a mesh network structure centered on the head-end node; Among them, the micro-power wireless and carrier dual-mode communication network is composed of a head-end node and a tail-end node. One head-end node and multiple tail-end nodes form a mesh network centered on the head-end node.

6. A control method for a flexible interconnection technology in a low-voltage power distribution area as described in claim 5, characterized in that: The remote monitoring and control of the low-voltage power distribution area grid based on remote communication technology includes, through the controller and the energy management system, predicting data to specify optimization scheduling instructions for the interconnection system, realizing real-time monitoring and control of the operation status of the substation area interconnection system. At the same time, the substation area interconnection based on flexible DC technology combines the power distribution Internet of Things technology architecture to carry out intelligent transformation of the medium and low-voltage Internet of Things, replacing the low-voltage main incoming switch and feeder switch in the substation area of the system, deploying primary and secondary integrated intelligent circuit breakers, sensing terminals, and environmental monitoring Internet of Things end devices, and entering the cloud master station system through wireless communication to achieve full perception of the operation status of the substation area.

7. A system using a control method for a flexible interconnection technology in a low-voltage power distribution area as described in any one of claims 1 to 6, characterized in that: It includes an initialization module, a grid diagnosis module, a grid control module, an information display module, and a grid monitoring and control module; The initialization module is used to collect data, location status, control output loop switch access status, and status information of the low-voltage power distribution area grid, and monitor the operating conditions of the low-voltage flexible interconnection device; The grid diagnosis module is used to analyze and process data, diagnose the grid status, and feedback grid anomalies; The grid control module is used to automatically adjust the low-voltage power distribution area grid to keep the grid operating in a normal state; The information display module is used to display grid status information and control information; The grid monitoring and control module is used to remotely monitor and control the low-voltage power distribution area grid through remote communication technology.

8. A computer device, including a memory and a processor, where the memory stores a computer program, characterized in that, when the processor executes the computer program, it implements the steps of a control method for a flexible interconnection technology in a low-voltage power distribution area as described in any one of claims 1 to 6.

9. A computer-readable storage medium, on which a computer program is stored, characterized in that, When the computer program is executed by a processor, it implements the steps of a control method for a flexible interconnection technology in a low-voltage distribution area described in any one of claims 1 to 6.

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