A photovoltaic power station area management system based on fusion terminal and management method thereof

Abstract

The present invention belongs to the field of power management equipment, and specifically relates to a photovoltaic power station area management method based on a fusion terminal and a management method thereof. The management system is used to manage the operation process of a power supply area where a distributed photovoltaic power station is installed. Among them, the power supply area is composed of a power generation side, a power supply side, a power consumption side and a distribution main station; the area includes: an area transformer, a centralized energy storage device and a low-voltage power grid on the power supply side; a distributed photovoltaic power generation unit on the power generation side, each photovoltaic power generation unit is composed of a photovoltaic power generation panel and an inverter. Various load devices on the power consumption side; the power consumption side is electrically connected to the low-voltage power grid. The management system includes: multiple photovoltaic switches, multiple energy meters, a concentrator, a first Internet of Things communication unit, a second Internet of Things communication unit, and a fusion terminal. The present invention solves the problems in the existing distributed photovoltaic power station management system that multiple monitoring and protection functions of the equipment operate independently, resulting in low area management efficiency and untimely response to faults.

Description

Technical Field

[0001] The present invention belongs to the field of power management equipment, and in particular relates to a photovoltaic power station area management method based on a fusion terminal and a management method thereof. Background Art

[0002] Solar photovoltaic power generation is a form of power generation that uses the photovoltaic principle of solar photovoltaic cells to directly convert solar energy into electrical energy. Solar photovoltaic power generation systems are generally composed of solar panels, solar controllers, battery packs, DC-AC inverters and AC power distribution equipment. Solar panels are the core part of solar photovoltaic power generation systems. They use the photovoltaic effect of semiconductors to directly convert light energy into electrical energy and send it to batteries for storage. If the solar power generation system is connected in parallel with the AC power grid (photovoltaic grid-connected power generation), the solar photovoltaic power generation system can save the battery part, and the solar controller and DC-AC inverter are combined into one. The investment in the power generation system is the lowest, the cost is reduced, and the impact of the battery on the environment can be reduced. Therefore, the solar grid-connected power generation system is the main form of photovoltaic power generation in the future. Under this trend, photovoltaic switches came into being. The data collection and control of photovoltaic switches are also very important in the entire power system.

[0003] However, in actual application scenarios, the power of photovoltaic power generation is extremely unstable and easily affected by the environment. The power generation capacity of photovoltaic power stations fluctuates greatly and cannot be used as the main energy supply in the substation. The existing power management system of the power supply substation containing distributed photovoltaic power stations needs to solve various tasks such as power quality monitoring, energy information measurement, circuit overload and short circuit protection, and anti-islanding protection of power supply equipment. This requires managers to manage the operating status of different equipment in the substation in real time, which has many tasks and is difficult to manage. Summary of the invention

[0004] In order to solve the problems in existing distributed photovoltaic power station management systems where multiple monitoring and protection devices operate independently, resulting in low efficiency in area management and untimely response to faults, the present invention provides a photovoltaic power station area management method based on a fusion terminal and a management method thereof.

[0005] The present invention is implemented by the following technical solutions:

[0006] A photovoltaic power station area management system based on a fusion terminal, the management system is used to manage the power distribution relationship of the power supply area where a distributed photovoltaic power station is installed. Among them, the power supply area is composed of a power generation side, a power supply side, a power consumption side and a distribution main station. Specifically including: an area transformer, a centralized energy storage device and a low-voltage power grid on the power supply side; a plurality of distributed photovoltaic power generation units on the power generation side, each photovoltaic power generation unit is composed of a set of photovoltaic power generation panels and an inverter. Various load devices used by users on the power consumption side; the power consumption side is electrically connected to the low-voltage power grid. The distribution main station is composed of a server of a remote management center. In particular, in the area of ​​the present invention, each user may be both a user on the power generation side and a user on the power consumption side.

[0007] The photovoltaic power station area management system provided by the present invention includes: multiple photovoltaic switches, multiple electric energy meters, a concentrator, a first Internet of Things communication unit, a second Internet of Things communication unit, and a fusion terminal.

[0008] The photovoltaic switch uses a circuit breaker with intelligent leakage automatic reclosing function. The photovoltaic switch is used to control the grid connection state of the power output of each inverter to the low-voltage power grid.

[0009] The electric energy meter is installed at the power consumption node of each power user within the power supply area to measure the energy consumption information on the user side.

[0010] The concentrator is connected to the electric energy meter at each power consumption node in the power supply area to collect the energy consumption information of the power consumption node.

[0011] The first IoT communication unit is used to realize communication connection between each inverter and the fusion terminal. The first IoT communication unit sends the state parameters of the inverter to a fusion terminal.

[0012] The second IoT communication unit is used to realize communication connection between each photovoltaic switch and the fusion terminal. The second IoT communication unit sends the state parameter of the photovoltaic switch to the fusion terminal, and sends a switching instruction generated by the fusion terminal to the photovoltaic switch.

[0013] The fusion terminal is used to autonomously manage the equipment in the power supply area and respond to the data collection instructions and equipment management instructions issued by the distribution master station. The fusion terminal is used to implement the following functions: obtain the energy consumption information of all power users in the power supply area collected by the concentrator, generate the load response data in the area, and send it to the distribution master station. Collect the power generation information of all inverters in the power supply area, generate the power supply data in the area, and send it to the distribution master station. Evaluate the grid-connected voltage and current harmonics on the low-voltage power grid, analyze the power quality information of the power supply area, and send it to the distribution master station. Generate a control instruction based on the power supply and demand relationship of the area to switch the charging and discharging state of the centralized energy storage device. Generate a switching instruction based on the master station's judgment result on the islanding effect in the area, and drive the photovoltaic switch to cut off the electrical connection between all inverters in the power supply area and the low-voltage power grid. Analyze the collected load response data and power supply data, and then generate a corresponding switching instruction when an overload or short circuit fault occurs on the power generation side or the power supply side, and cut off the electrical connection between the photovoltaic power generation unit at the fault node and the low-voltage power grid.

[0014] As a further improvement of the present invention, the fusion terminal is connected to the power distribution master station via 4G, 5G mobile communication or Ethernet communication. The fusion terminal is connected to the centralized energy storage device via an RS485 serial bus interface. The fusion terminal and the concentrator are connected via Ethernet communication.

[0015] As a further improvement of the present invention, the concentrator is connected to the electric energy meter by power carrier communication. The first IoT communication unit and the second IoT communication unit are both connected to the fusion terminal by power carrier communication.

[0016] As a further improvement of the present invention, the first IoT communication unit is connected to the inverter through a RS485 serial bus interface. The second IoT communication unit is connected to the photovoltaic switch through a RS485 serial bus interface.

[0017] As a further improvement of the present invention, in the power supply area, when a node corresponding to any photovoltaic switch has a disconnection event, the fusion terminal will automatically generate a corresponding alarm state and report the alarm state to the power distribution master station. When the fault state that triggers the disconnection is eliminated or the photovoltaic switch receives a closing switching instruction issued by the intelligent fusion terminal, the closing state of the current node is automatically restored.

[0018] As a further improvement of the present invention, the fault conditions that trigger the photovoltaic switch to cause a tripping event include: zero loss, overload, short circuit short delay, phase loss, undervoltage, overvoltage, grounding, remote test, button test, manual, short circuit instantaneous, soft remote control, hard remote control, harmonic abnormality, three-phase imbalance, contact overtemperature, and anti-island protection.

[0019] As a further improvement of the present invention, the inverter in each photovoltaic power generation unit has an anti-islanding protection function. When the inverter determines that the current node has an islanding effect based on the relationship between the grid-connected bus frequency and the power frequency, it will be disconnected from the grid within a preset time period, and an islanding protection alarm status will be generated and sent to the fusion terminal through the first IoT communication unit. The fusion terminal reports the islanding protection alarm status to the distribution master station. Within a preset period, when the number of nodes that generate an islanding protection alarm status in a certain power supply area received by the distribution master station is greater than a preset safety threshold, it is determined that a power outage event has occurred in the current power supply area, and then an active anti-islanding instruction is generated and sent to the fusion terminal. When the fusion terminal receives the active anti-islanding instruction, it drives the photovoltaic switch to cut off the grid-connected state of the photovoltaic power generation unit in the power supply area.

[0020] As a further improvement of the present invention, when the operation and maintenance management personnel need to conduct a full-area maintenance of the substation or troubleshoot a branch line, the corresponding operation request is reported to the distribution master station. When responding to the operation request, the distribution master station issues a switching instruction to the fusion terminal to disconnect all photovoltaic power generation units connected to the grid on the lines within the operation range. After receiving the instruction, the fusion terminal drives the photovoltaic switch of the corresponding node to execute the instruction and isolates the node of the corresponding photovoltaic power generation unit.

[0021] As a further improvement of the present invention, the source of electric energy in the power supply area includes electric energy outside the area distributed by the transformer, and electric energy meters within the area generated by distributed photovoltaic power generation units. The power distribution master station analyzes the current power supply and demand relationship in the area based on the uploaded real-time load response data, power supply data and power quality information. Then, the transmission and distribution capacity of the transformer in the area is dynamically adjusted according to the supply and demand relationship, and instructions are issued to the fusion terminal to switch the charging and discharging state of the centralized energy storage device.

[0022] The present invention also includes a photovoltaic power station area management method based on a fusion terminal, which is applied to the photovoltaic power station area management system based on the fusion terminal as described above, and is used to manage the power supply area according to the operating status of each device in the area. The photovoltaic power station area management method includes the following contents:

[0023] (1) Obtain the energy consumption information of all power users in the power supply area collected by the concentrator, generate load response data in the area, and send it to the distribution master station.

[0024] (2) Collect power generation information of all inverters in the power supply area, generate power supply data within the area, and send it to the main distribution station.

[0025] (3) Evaluate the grid-connected voltage and current harmonics on the low-voltage power grid, analyze the power quality information of the power supply area, and send it to the main distribution station.

[0026] (4) Analyze the collected load response data and power supply data, and then generate corresponding switching instructions when an overload or short circuit fault occurs on the power generation side or the power supply side, so as to cut off the electrical connection between the photovoltaic power generation unit at the fault node and the low-voltage power grid.

[0027] (5) Generate a switching command based on the master station's determination of the islanding effect in the substation area, and then drive the photovoltaic switch to cut off the electrical connection between all inverters in the power supply substation area and the low-voltage power grid when a fault occurs in the low-voltage power supply network of the entire substation area.

[0028] (6) When a maintenance request is generated in the substation area, all grid-connected photovoltaic power generation units contained in the lines within the operation range are analyzed, and then the photovoltaic switches of the corresponding nodes are driven to execute instructions to isolate the nodes of the corresponding photovoltaic power generation units.

[0029] (7) Based on the real-time load response data, power supply data and power quality information obtained in the substation, analyze the current power supply and demand relationship in the substation; dynamically adjust the transmission and distribution capacity of the substation transformer according to the supply and demand relationship, and issue instructions to the fusion terminal to switch the charging and discharging status of the centralized energy storage device.

[0030] The technical solution provided by the present invention has the following beneficial effects:

[0031] The present invention provides a photovoltaic power station area management system based on a fusion terminal, which can integrate the equipment and information of the power consumption side, power generation side, power supply side and management main station in the power supply area through the fusion terminal, photovoltaic switch, concentrator and Internet of Things communication device. The purpose of dynamic management of different equipment in the overall system in real time. In the system, the fusion terminal serves as the hub of the system, and monitors the power supply area in real time to quickly discover and deal with fault conditions that occur on the power generation side or the power consumption side in the power supply area. Thereby improving the management efficiency of the area and reducing the difficulty of management work in the area. The present invention can also connect the electric energy generated by the photovoltaic power generation unit in the power supply area to the grid, realize the on-site consumption of energy in the area, and reduce the transmission loss of energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0033] Figure 1 This is a structural topology diagram between a photovoltaic power station area management system based on a fusion terminal and equipment in a power supply area provided in Example 1 of the present invention.

[0034] Figure 2This is a task flow chart of the implementation process of a photovoltaic power station area management method based on a fusion terminal provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] Example 1

[0037] This embodiment provides a photovoltaic power station area management system based on a fusion terminal, which is used to manage the power distribution relationship of the power supply area where a distributed photovoltaic power station is installed. Figure 1 As shown, the power supply area is composed of the power generation side, the power supply side, the power consumption side and the distribution main station. Specifically including: the area transformer on the power supply side, the centralized energy storage device and the low-voltage power grid. Multiple distributed photovoltaic power generation units on the power generation side, each photovoltaic power generation unit is composed of a set of photovoltaic power generation panels and inverters. Various load devices used by users on the power consumption side; the power consumption side is electrically connected to the low-voltage power grid. The distribution main station is composed of the server of the remote management center. In particular, in the area of ​​this embodiment, each user may be both a user on the power generation side and a user on the power consumption side.

[0038] The photovoltaic power station area management system provided in this embodiment includes: multiple photovoltaic switches, multiple electric energy meters, a concentrator, a first Internet of Things communication unit, a second Internet of Things communication unit, and a fusion terminal.

[0039] Photovoltaic switches use circuit breakers with intelligent leakage automatic reclosing function. Photovoltaic switches are used to control the grid-connected state of the power output of each inverter to the low-voltage power grid. Photovoltaic switches select various types of electronic high-breaking residual current operated circuit breakers available on the market. Such products usually have residual current display, real-time load current display, phase voltage display, etc., which can facilitate users to timely understand the working status of photovoltaic power generation units.

[0040] At the same time, photovoltaic switches usually also have the function of automatically reclosing after the residual current circuit breaker is disconnected due to residual current undervoltage, overvoltage, and phase loss. It also provides indirect contact protection to prevent fire hazards caused by ground fault current caused by equipment insulation damage. It can also be used to distribute electric energy and protect the line from overload and short circuit; it has protection functions for line overvoltage, undervoltage, phase loss, and zero break on the power supply side.

[0041] The energy meter is installed at the power consumption node of each power user in the power supply area to measure the energy consumption information on the user side. The energy meter adopts the existing smart energy meter with data storage and communication functions.

[0042] The concentrator is connected to the electric energy meter at each power consumption node in the power supply area, and then collects the energy consumption information of the power consumption node; it is the central management device and control device of the remote centralized meter reading system. The concentrator is responsible for functions such as regular reading of terminal data, system command transmission, data communication, network management, event recording, and horizontal transmission of data. In this embodiment, the concentrator uses the power carrier communication method to communicate with the electric energy meter.

[0043] The first IoT communication unit is used to realize communication connection between each inverter and the fusion terminal. The first IoT communication unit sends the state parameters of the inverter to a fusion terminal. The second IoT communication unit is used to realize communication connection between each photovoltaic switch and the fusion terminal. The second IoT communication unit sends the state parameters of the photovoltaic switch to the fusion terminal and sends a switching instruction generated by the fusion terminal to the photovoltaic switch.

[0044] In the system of this embodiment, in the uplink segment, the first IoT communication unit and the second IoT communication unit are both connected to the fusion terminal by the communication method of low-voltage power line carrier communication PLC. In the downlink segment, the first IoT communication unit is connected to the inverter through the RS485 serial bus interface. The second IoT communication unit is connected to the photovoltaic switch through the RS485 serial bus interface. Power line carrier communication processes the data signal as a digital signal and modulates it to a certain carrier frequency (the dedicated frequency band for low-voltage power line carrier communication is 3-500kHz), and uses the existing power line for transmission. Compared with traditional modulation technology, power line carrier technology has the following advantages: strong anti-noise and anti-interference capabilities, reliable and stable communication; it has the ability to adapt to changes in the power line channel, and it is still possible to communicate successfully when individual subcarriers are interfered with; the data rate is high, usually more than tens of kbps.

[0045] The fusion terminal is used to autonomously manage the equipment in the power supply area and respond to the data collection instructions and equipment management instructions issued by the distribution master station. The fusion terminal is used to implement the following functions: obtain the energy consumption information of all power users in the power supply area collected by the concentrator, generate the load response data in the area, and send it to the distribution master station. Collect the power generation information of all inverters in the power supply area, generate the power supply data in the area, and send it to the distribution master station. Evaluate the grid-connected voltage and current harmonics on the low-voltage power grid, analyze the power quality information of the power supply area, and send it to the distribution master station. Generate a control instruction based on the power supply and demand relationship of the area to switch the charging and discharging state of the centralized energy storage device. Generate a switching instruction based on the master station's judgment result on the islanding effect in the area, and drive the photovoltaic switch to cut off the electrical connection between all inverters in the power supply area and the low-voltage power grid. Analyze the collected load response data and power supply data, and then generate a corresponding switching instruction when an overload or short circuit fault occurs on the power generation side or the power supply side, and cut off the electrical connection between the photovoltaic power generation unit at the fault node and the low-voltage power grid.

[0046] Specifically, the power information uploaded by the fusion terminal to the power distribution master station includes the three-phase voltage, current, active power, reactive power, apparent power, voltage harmonics, and current harmonics of A, B, and C. Among them, the voltage and current harmonics include the 3rd, 5th, 7th, 9th, 11th, and 13th harmonics.

[0047] In the management system of this embodiment, the fusion terminal is connected to the power distribution master station via 4G, 5G mobile communication or Ethernet communication. The fusion terminal is connected to the centralized energy storage device via the RS485 serial bus interface. The fusion terminal and the concentrator are connected via Ethernet communication.

[0048] Combination Figure 1 It can be seen from the system structure topology diagram that the fusion terminal is the data collection center and management center of the entire management system. The fusion terminal can obtain the equipment information and internal power parameters of all photovoltaic switches and photovoltaic inverters in the power supply area. Then, the daily power generation of the photovoltaic power generation system is determined based on this information; and the daily power generation, voltage, current and alarm events are uploaded to the distribution master station of the power supply area. In addition, the power consumption on the user side and the voltage and current parameters of the low-voltage power grid can be updated in real time through the intelligent fusion terminal of the area. At the same time, when the photovoltaic switch is disconnected or an alarm event occurs, the generated event information is immediately sent to the distribution master station. The fusion terminal can quickly respond and make decisions for the fault state of the area that needs to be responded to in time to avoid further development of the fault state. The continuous monitoring of the system operation status and the analysis of the energy supply and demand relationship are managed by the distribution master station. This significantly improves the management efficiency of the system and improves the real-time nature of various actions to deal with fault states.

[0049] In the power supply area of ​​the management system in this embodiment, when a disconnection event occurs at a node corresponding to any photovoltaic switch, the fusion terminal will automatically generate a corresponding alarm state and report the alarm state to the power distribution master station. When the fault state that triggers the disconnection is eliminated or the photovoltaic switch receives a closing switching instruction issued by the intelligent fusion terminal, the closing state of the current node is automatically restored.

[0050] In addition, in the management system of this embodiment, visual management of system management data is also achieved through various terminal devices. Through the management system, users and managers can choose to view various types of local power information, and according to these basic power parameters, daily power generation, and alarm events, they can timely understand the operation of the photovoltaic power generation unit and the energy consumption of power users at each node. In addition, when an alarm event occurs, the local on-duty manager can also find and deal with the problem in time, avoiding further expansion of the fault or loss. For example, when a disconnection event occurs at any node in the substation, the user can also view the detailed information sent to the fusion terminal event to obtain the cause of the disconnection. Among them, the fault states that trigger the disconnection event of the photovoltaic switch include: zero lack, overload, short circuit short delay, phase lack, undervoltage, overvoltage, grounding, remote test, button test, manual, short circuit instantaneous, soft remote control, hard remote control, harmonic abnormality, three-phase imbalance, contact overtemperature, and anti-island protection. For example, when an overload problem occurs, the user can also quickly solve the problem by querying the relevant operation manual. Similarly, if other alarm events occur, users can view detailed information about the event sent to the fusion terminal, obtain the cause of the alarm, and clarify the current operating status of the distributed photovoltaic power station.

[0051] In this embodiment, the inverter in each photovoltaic power generation unit has an anti-islanding protection function. When the inverter determines that the current node has an islanding effect based on the relationship between the grid-connected bus frequency and the power frequency, it will be disconnected from the grid within a preset time period, and an islanding protection alarm status will be generated and sent to the fusion terminal through the first IoT communication unit. The fusion terminal reports the islanding protection alarm status to the distribution master station. Within a preset period, when the number of nodes that generate an islanding protection alarm status in a certain power supply area received by the distribution master station is greater than a preset safety threshold, it is determined that a power outage event has occurred in the current power supply area, and then an active anti-islanding instruction is generated and sent to the fusion terminal. When the fusion terminal receives the active anti-islanding instruction, it drives the photovoltaic switch to cut off the grid-connected state of the photovoltaic power generation unit in the power supply area.

[0052] In particular, in order to achieve rapid data tracing and fault location, all data collected and reported to the power distribution master station by the fusion terminal in this embodiment include basic information such as model name, port, address, description, manufacturer ID, reporting flag, node ID, product ID, etc.

[0053] In this management system, when the operation and maintenance management personnel need to conduct a full-area maintenance of the substation or troubleshoot a branch line, they report the corresponding operation request to the distribution master station. When responding to the operation request, the distribution master station issues a switching instruction to the fusion terminal to disconnect all photovoltaic power generation units connected to the grid on the lines within the operation range. After receiving the instruction, the fusion terminal drives the photovoltaic switch of the corresponding node to execute the instruction and isolate the node of the corresponding photovoltaic power generation unit.

[0054] In the power supply area of ​​the present embodiment, since a large number of distributed photovoltaic power generation units are configured, the power supply area mainly has two sources of electric energy, namely, the electric energy outside the area distributed by the transformer, and the electric energy within the area generated by the distributed photovoltaic power generation units. In order to manage the supply and demand relationship of electric energy within the area, improve the grid connection rate of photovoltaic discharge power sources, and reasonably allocate energy. The power distribution master station of this embodiment analyzes the current supply and demand relationship of electric energy in the area based on the uploaded real-time load response data, power supply data, and power quality information. Then, based on the supply and demand relationship, with the goal of maximizing the utilization of electric energy within the area, the transmission and distribution capacity of the transformer in the area is dynamically adjusted, and instructions are issued to the fusion terminal to switch the charging and discharging status of the centralized energy storage device. Example 2

[0055] This embodiment provides a photovoltaic power station area management method based on a fusion terminal, which is applied to the photovoltaic power station area management system based on a fusion terminal as in Example 1. The management method is used to manage the equipment in the power supply area according to the operating status of each device in the area. Figure 2 As shown, the photovoltaic power station area management method includes the following contents:

[0056] (1) Obtain the energy consumption information of all power users in the power supply area collected by the concentrator, generate load response data in the area, and send it to the distribution master station.

[0057] (2) Collect power generation information of all inverters in the power supply area, generate power supply data within the area, and send it to the main distribution station.

[0058] (3) Evaluate the grid-connected voltage and current harmonics on the low-voltage power grid, analyze the power quality information of the power supply area, and send it to the main distribution station.

[0059] (4) Analyze the collected load response data and power supply data, and then generate corresponding switching instructions when an overload or short circuit fault occurs on the power generation side or the power supply side, so as to cut off the electrical connection between the photovoltaic power generation unit at the fault node and the low-voltage power grid.

[0060] (5) Generate a switching command based on the master station's determination of the islanding effect in the substation area, and then drive the photovoltaic switch to cut off the electrical connection between all inverters in the power supply substation area and the low-voltage power grid when a fault occurs in the low-voltage power supply network of the entire substation area.

[0061] (6) When a maintenance request is generated in the substation area, all grid-connected photovoltaic power generation units contained in the lines within the operation range are analyzed, and then the photovoltaic switches of the corresponding nodes are driven to execute instructions to isolate the nodes of the corresponding photovoltaic power generation units.

[0062] (7) Based on the real-time load response data, power supply data and power quality information obtained in the substation, analyze the current power supply and demand relationship in the substation; dynamically adjust the transmission and distribution capacity of the substation transformer according to the supply and demand relationship, and issue instructions to the fusion terminal to switch the charging and discharging status of the centralized energy storage device.

[0063] Each management task in this embodiment is automatically executed by the device, thereby achieving real-time monitoring and dynamic management of the power grid in the substation area, which greatly improves the management efficiency of the system and reduces the workload of the operation and maintenance management personnel.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A photovoltaic power station area management system based on a fusion terminal, characterized in that: It is used to manage the power distribution relationship of the power supply area where a distributed photovoltaic power station is installed. The power supply area consists of a power generation side, a power supply side, a power consumption side and a power distribution main station; the power supply side includes an area transformer, a centralized energy storage device and a low-voltage power grid; the power generation side includes a plurality of distributed photovoltaic power generation units, each of which consists of a set of photovoltaic power generation panels and an inverter; the power consumption side includes various load devices used by users, and the power consumption side is electrically connected to the low-voltage power grid; the photovoltaic power station area management system includes: A plurality of photovoltaic switches, which use circuit breakers with intelligent leakage automatic reclosing function, and the photovoltaic switches are used to control the grid connection state of the electric energy output by each inverter to be transmitted to the low-voltage power grid; Multiple electric energy meters are installed at the power consumption nodes of each power user in the power supply area to measure the energy consumption information on the user side; The concentrator is connected to the electric energy meter at each power consumption node in the power supply area to collect the energy consumption information of the power consumption node; A first IoT communication unit, which is used to realize communication connection between each inverter and the fusion terminal; the first IoT communication unit sends the state parameters of the inverter to a fusion terminal; A second IoT communication unit is used to realize communication connection between each photovoltaic switch and the fusion terminal; the second IoT communication unit sends the state parameters of the photovoltaic switch to the fusion terminal, and sends a switching instruction generated by the fusion terminal to the photovoltaic switch; and A fusion terminal is used to autonomously manage the equipment in the power supply area and respond to the data collection instructions and equipment management instructions issued by the distribution master station; the fusion terminal is used to: obtain the energy consumption information of all power users in the power supply area collected by the concentrator, generate the load response data in the area, and send it to the distribution master station; collect the power generation information of all inverters in the power supply area, generate the power supply data in the area, and send it to the distribution master station; evaluate the grid-connected voltage and current harmonics on the low-voltage power grid, analyze the power quality information of the power supply area, and send it to the distribution master station; generate a control instruction according to the power supply and demand relationship of the area to switch the charging and discharging state of the centralized energy storage device; generate a switching instruction according to the master station's determination result of the islanding effect in the area, drive the photovoltaic switch to cut off the electrical connection state between all inverters in the power supply area and the low-voltage power grid; analyze the collected load response data and power supply data, and then generate a corresponding switching instruction when an overload or short circuit fault occurs on the power generation side or the power supply side, and cut off the electrical connection state between the photovoltaic power generation unit at the fault node and the low-voltage power grid.

2. The photovoltaic power station area management system based on the fusion terminal according to claim 1, characterized in that: The fusion terminal is connected to the power distribution master station via 4G, 5G mobile communication or Ethernet communication; the fusion terminal is connected to the centralized energy storage device via an RS485 serial bus interface; the fusion terminal and the concentrator are connected to each other via Ethernet communication.

3. The photovoltaic power station area management system based on the fusion terminal according to claim 1, characterized in that: The concentrator is connected to the electric energy meter by means of power carrier communication; the first IoT communication unit and the second IoT communication unit are connected to the fusion terminal by means of power carrier communication.

4. The photovoltaic power station area management system based on the fusion terminal according to claim 1, characterized in that: The first IoT communication unit is connected to the inverter through an RS485 serial bus interface; the second IoT communication unit is connected to the photovoltaic switch through an RS485 serial bus interface.

5. The photovoltaic power station area management system based on the fusion terminal according to claim 4 is characterized in that: Within the power supply area, when a node corresponding to any photovoltaic switch experiences a power failure event, the fusion terminal will automatically generate a corresponding alarm status and report the alarm status to the distribution master station; when the fault state triggering the power failure is eliminated or the photovoltaic switch receives a closing switching instruction issued by the intelligent fusion terminal, the current node's closing state is automatically restored.

6. The photovoltaic power station area management system based on the fusion terminal according to claim 5, characterized in that: The fault conditions that trigger the photovoltaic switch to trip include: zero loss, overload, short circuit short delay, phase loss, undervoltage, overvoltage, grounding, remote test, button test, manual, short circuit instantaneous, soft remote control, hard remote control, harmonic abnormality, three-phase unbalance, contact overtemperature, and anti-island protection.

7. The photovoltaic power station area management system based on the fusion terminal according to claim 1, characterized in that: The inverter in each of the photovoltaic power generation units has an anti-islanding protection function. When the inverter determines that the current node has an islanding effect based on the relationship between the grid-connected bus frequency and the power frequency, it will be disconnected from the grid within a preset time period, and generate an islanding protection alarm status and send it to the fusion terminal through the first IoT communication unit; the fusion terminal reports the islanding protection alarm status to the distribution master station; within a preset period, when the number of nodes in a certain power supply area that have generated an islanding protection alarm status received by the distribution master station is greater than a preset safety threshold, it is determined that a power outage has occurred in the current power supply area, and an active anti-islanding instruction is generated and sent to the fusion terminal; when the fusion terminal receives the active anti-islanding instruction, it drives the photovoltaic switch to cut off the grid-connected status of the photovoltaic power generation unit in the power supply area.

8. The photovoltaic power station area management system based on the fusion terminal according to claim 7, characterized in that: When the operation and maintenance management personnel need to conduct a full-area maintenance on the substation or troubleshoot a branch line, the corresponding operation request is reported to the distribution master station; when responding to the operation request, the distribution master station issues a switching instruction to the fusion terminal to disconnect all photovoltaic power generation units connected to the grid on the lines within the operation range; after receiving the instruction, the fusion terminal drives the photovoltaic switch of the corresponding node to execute the instruction, thereby isolating the node of the corresponding photovoltaic power generation unit.

9. The photovoltaic power station area management system based on the fusion terminal according to claim 1, characterized in that: The sources of electric energy in the power supply area include electric energy outside the area distributed by transformers, and electric energy within the area generated by distributed photovoltaic power generation units; The distribution master station analyzes the current power supply and demand relationship in the substation based on the uploaded real-time load response data, power supply data and power quality information; then dynamically adjusts the transmission and distribution capacity of the substation transformer according to the supply and demand relationship, and issues instructions to the fusion terminal to switch the charging and discharging status of the centralized energy storage device.

10. A photovoltaic power station area management method based on a fusion terminal, characterized in that: It is applied to the photovoltaic power station area management system based on the fusion terminal as described in any one of claims 1 to 9, and is used to manage the power supply area according to the operating status of each device in the area; the photovoltaic power station area management method includes the following contents: (1) Obtain the energy consumption information of all power users in the power supply area collected by the concentrator, generate load response data in the area, and send it to the distribution master station; (2) Collect power generation information of all inverters in the power supply area, generate power supply data in the area, and send it to the power distribution master station; (3) Evaluate the grid-connected voltage and current harmonics on the low-voltage power grid, analyze the power quality information of the power supply area, and send it to the main distribution station; (4) Analyze the collected load response data and power supply data, and then generate corresponding switching instructions when an overload or short circuit fault occurs on the power generation side or the power supply side, and cut off the electrical connection between the photovoltaic power generation unit at the fault node and the low-voltage power grid; (5) Generate a switching command based on the master station's determination of the islanding effect in the substation area, and then drive the photovoltaic switch to cut off the electrical connection between all inverters in the power supply substation area and the low-voltage power grid when a fault occurs in the low-voltage power supply network of the entire substation area; (6) When a maintenance operation request is generated in the substation area, all grid-connected photovoltaic power generation units included in the lines within the operation range are analyzed, and then the photovoltaic switches of the corresponding nodes are driven to execute instructions to isolate the nodes of the corresponding photovoltaic power generation units; (7) Analyze the current power supply and demand relationship in the substation based on the real-time load response data, power supply data and power quality information obtained in the substation; The transmission and distribution capacity of the substation transformer is dynamically adjusted according to the supply and demand relationship, and instructions are issued to the fusion terminal to switch the charging and discharging status of the centralized energy storage device.

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