Multi-energy cooperative control cabinet for intelligent micro-grid and control method

Abstract

The invention discloses a multi-energy cooperative control cabinet for an intelligent micro-grid and a control method, and relates to the technical field of micro-grid intelligent control cabinets. A man-machine interaction module, an intelligent control module, a manual control module, an internal relay control module, a communication module, a power supply control module, a power supply sampling interface module, a circuit breaker control interface module and a UPS (Uninterrupted Power Supply) module are loaded in the control cabinet main body; wherein the man-machine interaction module comprises a touch screen, a grid-connected closing permission state indicating lamp and a manual and automatic mode selection module; the intelligent control module comprises a micro-grid control device and an NTPamp; a PTP clock service module; the internal relay control module comprises a relay logic control module and a DDC controller. The micro-grid controller controls the grid-connected and island mode automatic non-stop and non-power-cut switching control of the micro-grid in a self-adaptive mode according to the operation condition of the micro-grid.

Description

Technical Field

[0001] The present invention relates to the technical field of microgrid intelligent control cabinets, and in particular to a multi-energy collaborative control cabinet and a control method for an intelligent microgrid. Background Art

[0002] The microgrid control cabinet is based on the requirements of electrical wiring and control wiring. It assembles microgrid control devices, power sampling lines, circuit breaker opening and closing control buttons, communication equipment, human-computer interaction equipment, control logic modules and other microgrid monitoring equipment in a closed or semi-closed metal cabinet. The layout of this equipment should meet the requirements of the overall operation of the microgrid and facilitate maintenance while ensuring the safety of people and surrounding equipment. However, there are some problems in the implementation of existing microgrid control cabinets:

[0003] The existing microgrid control cabinet mainly realizes the independent microgrid operation status monitoring under automatic control and the switching control of the microgrid grid-connected to island mode. When the microgrid switches from grid-connected mode to island mode or from island mode back to grid-connected mode, manual intervention is still required. The switching process requires shutdown and power outage, resulting in insufficient continuity and reliability of the switching process, affecting the stability of power supply. The existing microgrid control cabinet lacks the ability to coordinate and optimize the control of multiple energy resources within the microgrid, between microgrids, and between microgrids and municipal power, and cannot effectively integrate and optimize the utilization of various distributed energy resources, resulting in low energy utilization efficiency and failure to maximize the utilization of renewable energy. Summary of the invention

[0004] In order to overcome the above-mentioned technical problems, the purpose of the present invention is to provide a multi-energy collaborative control cabinet and control method for a smart microgrid, so as to solve the problem in the prior art that the existing microgrid control cabinet lacks the ability to perform collaborative optimization control of multiple energy resources within the microgrid, between microgrids, and between the microgrid and the mains, and cannot effectively integrate and optimize the utilization of various distributed energy resources, resulting in low energy utilization efficiency and failure to maximize the utilization of renewable energy.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] The first aspect of the present invention is to provide a multi-energy collaborative control cabinet for an intelligent microgrid, comprising a control cabinet body, characterized in that a human-machine interaction module, an intelligent control module, a manual control module, an internal relay control module, a communication module, a power control module, a power sampling interface module, a circuit breaker control interface module and a UPS power module are installed inside the control cabinet body, wherein the human-machine interaction module includes a touch screen, a grid-connected closing permission status indicator light and a manual-automatic mode selection module; the intelligent control module includes a microgrid control device and an NTP&PTP clock service module; the internal relay control module includes a relay logic control module and a DDC controller; the power control module includes a power socket, a surge protector, a power air switch, a fuse, a DC power supply and a power extension terminal; the power sampling module includes a mains power sampling interface and a microgrid power sampling interface; the UPS power module includes a UPS power supply and a battery.

[0007] As a further solution of the present invention: the touch screen is connected to the microgrid control device via RS485 to realize the human-machine interaction interface function of the multi-energy collaborative control cabinet.

[0008] As a further solution of the present invention: the microgrid control device is connected to an external EMS management system, energy storage PCS and BMS, photovoltaic inverter and diesel generator controller through a communication module, the microgrid control device is connected to an external mains power supply and a microgrid power supply line through a power sampling interface module, and the microgrid control device controls a multi-circuit circuit breaker through a circuit breaker control interface module to realize the microgrid wind, solar, storage and diesel multi-energy coordinated adaptive control;

[0009] The multi-circuit circuit breaker includes a microgrid grid-connected point circuit breaker, a photovoltaic grid-connected circuit breaker, an energy storage grid-connected circuit breaker, a diesel generator grid-connected circuit breaker and a load circuit breaker.

[0010] As a further solution of the present invention: the NTP&PTP clock service module provides a unified clock timing service for the control cabinet body through the communication module.

[0011] As a further solution of the present invention: the manual control module manually controls the opening and closing of the multi-circuit circuit breaker through the internal relay control module and the circuit breaker control interface module, thereby realizing manual opening and closing control of the multi-circuit circuit breaker.

[0012] As a further solution of the present invention: the internal relay control module realizes logic control functions such as manual and automatic mode selection, synchronous grid connection permission status display, manual opening and closing control, and opening and closing status feedback through the relay logic control module and the DDC controller.

[0013] As a further solution of the present invention: the communication module includes a three-layer network switch and an Ethernet interface, an RS485 interface, a CAN interface, and an AUTBUS / LONWORKS interface.

[0014] The second aspect of the present invention is to provide a control method for a multi-energy collaborative control cabinet for a smart microgrid, which includes the working logic of the internal modules of the control cabinet, manual and automatic mode selection, local manual control, local automatic control, remote control, synchronous grid-connected permission control, blockchain-based evidence management, and touch screen human-computer interaction.

[0015] As a further solution of the present invention: the working logic of the internal module of the control cabinet includes the following steps:

[0016] S1. After the voltage and current sampling signals of the mains and microgrid are connected to the power sampling interface module, one way is connected to the UPS power module and the other way is connected to the intelligent control module;

[0017] S2. The voltage signal of the UPS power module is converted into the internal power supply of the control cabinet body by the UPS, and then converted into multiple AC and DC power supplies by the power control module to provide working power for the internal modules of the control cabinet body;

[0018] S3. The power sampling signal of the access intelligent control module is used as a monitoring signal of the microgrid operation status, and is used for the microgrid control device to identify the microgrid operation condition;

[0019] S4. The human-computer interaction module provides manual and automatic control mode settings for the intelligent control module, and can query the microgrid operating status through the intelligent control module;

[0020] S5. The intelligent control module works according to the manual and automatic modes set by the human-machine interaction module: when working in the manual control mode, the intelligent control module does not perform any automatic control, and the manual control module can perform multi-circuit circuit breaker opening and closing control operations;

[0021] S6. When working in the automatic control mode, the intelligent control module identifies different operating conditions of the microgrid according to the changes in the power sampling signal, and then performs corresponding automatic control on the microgrid.

[0022] As a further solution of the present invention: the intelligent control module performs corresponding automatic control on the microgrid, including real-time monitoring of the energy storage PCS, BMS, photovoltaic inverter, and diesel generator controller through communication module and EMS, and opening and closing control of multi-circuit circuit breakers through internal relay control module.

[0023] As a further solution of the present invention: the manual automatic control mode selection includes the following steps:

[0024] Y1, select through the manual and automatic mode selection module button SA1, if it is placed in the left gear, the "automatic" status indicator light is on, it is the automatic control state, if it is placed in the right gear, the "manual" status indicator light is on, it is the manual control state;

[0025] Y2. When SA1 selects the "manual" control mode, relay KA1 is energized, pins 5 and 9 are connected, and a DI signal is generated and input to the microgrid control device. At this time, the microgrid control device recognizes that the multi-energy system cabinet enters the "manual" control mode, otherwise it enters the "automatic" control mode;

[0026] Y3. When SA1 selects the "manual" control mode, the control buttons of all manual opening and closing control modules are connected to the ground, allowing manual opening and closing operations on each circuit breaker;

[0027] Y4. When SA1 selects the "automatic" control mode, the control buttons of all manual opening and closing control modules are disconnected from the ground, and manual opening and closing operations on each circuit breaker are prohibited;

[0028] Y5. Regardless of whether the "manual" or "automatic" control mode is selected, the circuit breaker's opening and closing status indicator lights will display normally.

[0029] As a further solution of the present invention: the local manual control method comprises the following steps:

[0030] Z1. In the "manual" control mode, after pressing the circuit breaker SB closing button (PCC circuit breaker, energy storage PCS short circuit breaker or photovoltaic circuit breaker), if the closing is successful, the closing status indicator of the corresponding circuit breaker will light up, and the manual closing operation of the circuit breaker is completed;

[0031] Z2. In the "manual" control mode, after pressing the SB opening button of the circuit breaker (PCC circuit breaker, energy storage PCS short circuit breaker or photovoltaic circuit breaker), if the opening is successful, the opening status indicator of the corresponding circuit breaker will light up, and the manual opening operation of the circuit breaker is completed;

[0032] Z3, the relay control module finally reports the operation information and feedback information to the microgrid control device through the DDC controller, and further reports to the EMS energy management system to realize the manual operation action and status monitoring and recording.

[0033] As a further solution of the present invention: the local automatic control method comprises the following steps:

[0034] X1. The microgrid control device monitors the change of control mode, and the default mode is automatic operation;

[0035] X2. In the local automatic control mode, if the "manual" control mode is detected, the automatic mode will be exited and the manual mode will be entered. If the remote control mode is detected, the automatic mode will be exited and the remote mode will be entered. The local manual control mode has the highest level, the remote control level is the second, and the local automatic control level is the lowest.

[0036] X3. Under local automatic control, when a sudden power outage is detected during grid-connected operation, the microgrid control device promptly controls the cutting off of the energy storage PCS grid power sampling signal, controls the PCC grid-connected circuit breaker / fast switch, and cuts off the corresponding non-important load circuit breakers or limit photovoltaic power generation according to the priority according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to the island operation state;

[0037] X4. Under local automatic control, when the PCC point is monitored for reverse power and the energy storage is allowed to charge, the microgrid control device controls the energy storage battery to charge. When there is still surplus after full charge, if access to the Internet is allowed, the reverse power is measured, otherwise the photovoltaic power is controlled to limit power generation;

[0038] X5. During grid-connected operation, when the deep charge and deep discharge setting time of the energy storage battery is reached, the microgrid control device controls the energy storage battery to perform deep charge and deep discharge maintenance operations;

[0039] X6. During island operation, when the monitored mains power is restored and the set grid-connection delay time parameter is reached, the microgrid control device promptly controls the connection of the energy storage PCS mains power sampling signal, and waits until the energy storage PCS automatically synchronizes and issues a grid-connection instruction to control and close the PCC point grid-connected circuit breaker / fast switch, and connects the corresponding non-important load circuit breaker or restores photovoltaic power generation according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to grid-connected operation;

[0040] X7. During island operation, when the monitored microgrid power generation is greater than the load and the energy storage is full, the microgrid control device controls the photovoltaic power generation to be limited. Conversely, if the energy storage SOC is insufficient, the microgrid control device cuts off non-important loads according to priority or starts the diesel generator to supplement energy.

[0041] As a further solution of the present invention: the remote control method comprises the following steps:

[0042] M1, the microgrid control device monitors the change of control mode, and the default is automatic operation mode;

[0043] M2. In the automatic operation mode, if the remote control mode is detected, the automatic mode will be exited and the remote mode will be entered;

[0044] M3. In remote control mode, when the EMS planned grid-connection to islanding instruction is detected, the microgrid control device promptly controls the cutting off of the energy storage PCS mains sampling signal, controls the PCC point grid-connected circuit breaker / fast switch, and cuts off the corresponding non-important load circuit breaker or the limited photovoltaic power generation power according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to the islanding operation state;

[0045] M4. When connected to the grid in remote control mode, the microgrid control device controls the energy storage PCS, photovoltaic inverter, diesel generator controller, and remote opening and closing of the circuit breaker according to the instructions issued by the EMS;

[0046] M5. When operating in an isolated island mode under remote control mode, after monitoring the mains power recovery and receiving the EMS isolated grid-connected command, the microgrid control device promptly controls the connection of the energy storage PCS mains power sampling signal, waits until the energy storage PCS automatically synchronizes and issues a grid-connected command, and controls the closing of the PCC point grid-connected circuit breaker / fast switch, and connects the corresponding non-important load circuit breaker or restores photovoltaic power generation according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to grid-connected operation;

[0047] M6. When operating in an isolated island mode in remote control mode, the microgrid control device controls the energy storage PCS, photovoltaic inverter, diesel generator controller, and remote opening and closing of the circuit breaker according to the instructions issued by the EMS.

[0048] As a further solution of the present invention: the synchronous grid connection permission control method comprises the following steps:

[0049] N1. When there is no voltage in the microgrid, the synchronous grid connection permission status indicator lights up, allowing the PCC point circuit breaker / fast switch closing operation in local automatic control mode, local manual control mode and remote control mode;

[0050] N2. When the microgrid PQ is connected to the grid, the synchronous grid connection permission status indicator lights up, allowing the PCC point circuit breaker / fast switch closing operation in local automatic control mode, local manual control mode or remote control mode;

[0051] N3. When the microgrid VF / VSG island is running, the synchronous grid connection permission status indicator will light up only when the microgrid control device detects that the phase, frequency and voltage between the microgrid and the mains reach the quasi-synchronous grid connection permission conditions after quasi-synchronous adjustment. Otherwise, it is forbidden to perform the PCC point circuit breaker / fast switch closing operation in any control mode. Quasi-synchronous adjustment includes three methods: VSG mode external remote adjustment, VF mode automatic phase lock and shutdown switching grid connection;

[0052] The VSG mode external remote adjustment method for quasi-synchronization comprises the following steps:

[0053] Q1. When it is necessary to transfer from an isolated grid to a grid-connected grid, if the main energy storage PCS has the external remote adjustment function of the VSG mode, the microgrid control device remotely adjusts the frequency and phase of the microgrid main energy storage PCS through the PDI method, and then adjusts the voltage through the PID remote reactive method;

[0054] Q2. When the frequency, phase and voltage of the microgrid are monitored to meet the quasi-synchronous grid-connected conditions, the microgrid control device controls the closing permission status indicator to light up, and automatically controls the PCC point circuit breaker / fast switch to close, completing the quasi-synchronous grid-connected closing;

[0055] Q3. When the switch is closed successfully, the microgrid control device controls the energy storage PCS mains sampling power supply line to be connected;

[0056] Q4: After the energy storage PCS detects that the city power is restored, it will automatically disconnect from the grid and shut down;

[0057] Q5. The microgrid control device controls the energy storage PCS to start the energy storage PCS grid-connected operation in PQ mode to achieve quasi-synchronous grid connection;

[0058] The VF mode automatic phase-locked quasi-synchronous adjustment method comprises the following steps:

[0059] W1. When it is necessary to transfer from an isolated grid to a grid-connected grid, if the main energy storage PCS has a VF automatic phase-locked synchronous grid-connected function, the microgrid control device will control and connect the energy storage PCS mains sampling power supply line;

[0060] W2. After the energy storage PCS detects that the mains sampling signal is restored, it automatically locks the phase and synchronizes. When the synchronization conditions are met, it notifies the microgrid control device to allow synchronous grid connection;

[0061] W3. After the microgrid control device receives the quasi-synchronous closing permission signal, it controls the closing permission status indicator to light up, and automatically controls the PCC point circuit breaker / fast switch to close, completing the quasi-synchronous grid-connected closing;

[0062] The shutdown switching and grid-connection method comprises the following steps:

[0063] R1. When it is necessary to transfer from an isolated grid to a grid-connected grid, if the main energy storage PCS does not have a quasi-synchronous regulation function, the microgrid control device directly controls the main energy storage PCS to shut down;

[0064] R2. When the energy storage PCS is shut down and the microgrid is out of power for more than 1 second, the microgrid control device controls the PCC grid connection point circuit breaker / fast switch to close;

[0065] R3. After the closing is successful, when it is monitored that the microgrid has restored power supply, the microgrid control device controls the energy storage PCS to restart in PQ grid-connected mode. After successful startup, the island-to-grid operation is completed.

[0066] As a further solution of the present invention: the touch screen human-computer interaction method comprises the following steps:

[0067] T1, the touch screen is a capacitive touch screen, connected to the microgrid control device via RS485;

[0068] T2, the touch screen mainly displays the operation configuration of the microgrid, the main monitoring and metering data of the mains and microgrid, and important alarm information;

[0069] T3. By switching pages, you can query multiple pages of information and the operating parameters issued by EMS.

[0070] Beneficial effects of the present invention:

[0071] In the present invention, the control modes are set to solve the operation problems of the three modes of local manual, local automatic and remote control; in the automatic control mode, the microgrid controller controls the microgrid to solve the problems of automatic non-stop and non-power-off switching control of the grid-connected mode and the island mode according to the operating conditions of the microgrid in an adaptive manner, including the multi-energy coordinated control within the microgrid and the mutual scheduling of energy between the microgrid and the mains; in the manual control mode, according to the needs of debugging and maintenance, the maintenance personnel can control the opening and closing of multi-circuit circuit breakers through the manual opening and closing control module, providing a safe and convenient operation interface for maintenance; in the remote mode, the microgrid control device realizes point-to-point control of the microgrid control equipment and circuit breakers and modification of control parameters according to the instructions issued by the EMS system. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] The present invention will be further described below in conjunction with the accompanying drawings.

[0073] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0074] Figure 2 It is a schematic diagram of the structure of the power control module of the present invention;

[0075] Figure 3 It is a schematic diagram of the structure of the manual control module of the present invention;

[0076] Figure 4 It is a structural schematic diagram of an internal relay control module of the present invention;

[0077] Figure 5 It is a schematic diagram of the working logic of the internal modules of the present invention;

[0078] Figure 6This is a schematic diagram of the implementation principle of the manual automatic control mode selection of the present invention;

[0079] Figure 7 This is a schematic diagram of the implementation principle of the manual opening and closing control of the present invention;

[0080] Figure 8 It is a local automatic control logic schematic diagram of the present invention;

[0081] Fig. 9 It is a remote control logic schematic diagram of the present invention;

[0082] Fig.10 A schematic diagram of synchronous grid connection permission control logic of the present invention;

[0083] Fig.11 This is a schematic diagram of the VSG mode external remote adjustment and synchronization adjustment logic of the present invention;

[0084] Fig.12 It is a logic diagram of automatic phase-locked quasi-synchronous regulation in VF mode of the present invention;

[0085] Fig.13 This is a schematic diagram of the shutdown switching and grid-connected control logic of the present invention.

[0086] In the figure: 1. Control cabinet body; 2. Touch screen; 3. Grid-connection permission status indicator; 4. Manual-automatic mode selection module; 5. Microgrid control device; 6. NTP&PTP clock service module; 7. Manual control module; 8. Relay logic control module; 9. Communication module; 10. Power socket; 11. Surge lightning protector; 12. AC power sampling interface; 13. Microgrid power sampling interface; 14. Circuit breaker control interface module; 15. DDC controller; 16. Power air switch; 17. Fuse; 18. DC power supply; 19. Power extension terminal; 21. UPS power supply; 22. Battery. DETAILED DESCRIPTION

[0087] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0088] Example 1

[0089] like Figure 1-Figure 4As shown, the present invention discloses a multi-energy collaborative control cabinet for a smart microgrid, including a control cabinet body 1, wherein a human-machine interaction module, an intelligent control module, a manual control module 7, an internal relay control module, a communication module 9, a power supply control module, a power supply sampling interface module, a circuit breaker control interface module 14 and a UPS power supply module are installed inside the control cabinet body 1, wherein the human-machine interaction module includes a touch screen 2, a grid-connected closing permission status indicator 3 and a manual-automatic mode selection module 4. It should be noted that the touch screen 2 is a terminal device for interacting with a user, and the touch screen 2 can be a resistive, capacitive or infrared type, and the specific specifications are determined by those skilled in the art according to the use of the control cabinet body 1. The scene is adaptively selected, the touch screen 2 is installed in the middle of the front of the control cabinet body 1, and the grid-connected closing permission status indicator 3 is installed in the middle of the front of the control cabinet body 1 on one side close to the touch screen 2. When the grid-connected closing permission status indicator 3 is in a normally on state, it indicates that the control cabinet body 1 can perform various operations normally. The manual-automatic mode selection module 4 is used to select the working mode of the control cabinet body 1, specifically including manual mode and automatic mode; the intelligent control module includes a microgrid control device 5 and an NTP&PTP clock service module 6. It should be noted that the NTP&PTP clock service module 6 includes a network time protocol and a precise time protocol. NTP&PTP The clock service module 6 improves the time consistency for each module inside the control cabinet body 1 through the network time protocol and the precise time protocol; the internal relay control module includes a relay logic control module 8 and a DDC controller 15. It should be noted that the DDC controller 15 realizes precise control and management through digital means to improve system efficiency, energy saving effect and comfort. Its working principle is to first obtain real-time data from various sensors (such as temperature sensors, humidity sensors, pressure sensors, etc.), and the DDC controller 15 is embedded with a control algorithm to perform real-time calculations according to the preset control strategy and sensor data. The control algorithm includes PID control, fuzzy control, logic control, etc. to ensure the system The system runs in the best state. According to the calculation results, the DDC controller sends a control signal to the actuator, and the actuator responds to the control signal to adjust the system parameters, such as wind speed, temperature, humidity, etc. The DDC controller 15 has a communication interface (such as BACnet, Modbus, LonWorks, etc.) and supports networking with other controllers and central management systems; the power control module includes a power socket 10, a surge protector 11, a power air switch 16, a fuse 17, a DC power supply 18 and a power extension terminal 19; the power sampling module includes a mains power sampling interface 12 and a microgrid power sampling interface 13; the UPS power module includes a UPS power supply 21 and a battery 22.

[0090] The touch screen 2 is connected to the microgrid control device 5 via RS485 to realize the human-machine interaction interface function of the multi-energy collaborative control cabinet. The microgrid control device 5 is responsible for the management of the control cabinet body 1 and the optimization of the operation of the microgrid, integrating the distributed energy resources of the control cabinet body 1 to improve the energy efficiency and reliability of the control cabinet body 1. The grid control device 5 can ensure the stability of the voltage and frequency in the microgrid, avoid voltage surges or dips, coordinate the operation of different power supplies and loads, maintain system stability, monitor the operating status of each component in the microgrid in real time, collect and analyze data, and provide decision support. The grid control device 5 mainly includes a central controller and a distributed control unit. , communication network, sensors and actuators. The central controller is the core control unit of the power grid control device 5, which is responsible for global coordination and management, processing data and executing control algorithms, and optimizing system operation. The distributed control units are distributed in various nodes of the microgrid, responsible for controlling local equipment, communicating with the central controller, executing instructions and feeding back data. The communication network connects the central controller and the distributed control units to realize data transmission and command delivery. Sensors and actuators monitor the voltage, current, frequency and other parameters in the microgrid in real time. The type of parameters is adaptively adjusted by technical personnel in this field according to the modules inside the control cabinet body 1, and the corresponding sensors and actuators are installed.

[0091] The microgrid control device 5 is connected to the external EMS management system, energy storage PCS and BMS, photovoltaic inverter and diesel generator controller through the communication module 9. The microgrid control device 5 is connected to the external mains and microgrid power supply lines through the power sampling interface module. The microgrid control device 5 controls the multi-circuit circuit breaker through the circuit breaker control interface module 14 to realize the microgrid wind, solar, storage and diesel multi-energy coordinated adaptive control. It should be noted that the microgrid control device 5 can be connected to the external EMS management system, energy storage PCS and BMS, photovoltaic inverter and diesel generator controller through the communication module 9, collect data from the external EMS management system, energy storage PCS and BMS, photovoltaic inverter and diesel generator controller, and control the multi-circuit circuit breaker through the control interface module 14 based on the data connected to the external EMS management system, energy storage PCS and BMS, photovoltaic inverter and diesel generator controller;

[0092] The multi-circuit circuit breaker includes a microgrid grid-connected point circuit breaker, a photovoltaic grid-connected circuit breaker, an energy storage grid-connected circuit breaker, a diesel generator grid-connected circuit breaker and a load circuit breaker. For example, when the microgrid grid-connected point circuit breaker needs to be disconnected, the microgrid control device 5 will control the microgrid grid-connected point circuit breaker to be disconnected through the control interface module 14. When the microgrid grid-connected point circuit breaker needs to be closed, the microgrid control device 5 will control the microgrid grid-connected point circuit breaker to be closed through the control interface module 14, thereby realizing the microgrid wind, photovoltaic, energy storage and diesel multi-energy coordinated adaptive control.

[0093] The NTP&PTP clock service module 6 provides a unified clock timing service for the control cabinet body 1 through the communication module 9. The NTP&PTP clock service module 6 improves the time consistency for each module inside the control cabinet body 1 through the network time protocol and the precision time protocol. The network time protocol is used to synchronize the computer system clock to the coordinated universal time through the network. The network time protocol uses a layered architecture and consists of multiple levels of time servers. According to the hierarchy, stratum 0 is the highest layer, which is generally an atomic clock or a GPS clock. The stratum 1 server is directly connected to the stratum 0 device, and the stratum 2 server obtains time from the stratum 1 server. The client sends a request to the server, and the server replies with the current timestamp. The client adjusts the local clock according to the receiving time and the sending time to ensure the time consistency between the server, the network device and the application. The precision time protocol is designed for applications that require high-precision time synchronization. There is a master clock in the precision time protocol. The slave clock obtains time from the master clock and synchronizes through the exchange of timestamp messages, including synchronization messages, delay request messages, and delay response messages. The slave clock adjusts according to the deviation between the received timestamp information and the local clock to achieve synchronization.

[0094] The manual control module 7 manually controls the opening and closing of the multi-circuit circuit breaker through the internal relay control module and the circuit breaker control interface module 14, thereby realizing manual opening and closing control of the multi-circuit circuit breaker.

[0095] The internal relay control module realizes the logic control functions such as manual and automatic mode selection, synchronous grid connection permission status display, manual opening and closing control and opening and closing status feedback through the relay logic control module 8 and the DDC controller 15.

[0096] The communication module 9 includes a three-layer network switch and an Ethernet interface, an RS485 interface, a CAN interface, and an AUTBUS / LONWORKS interface.

[0097] Example 2

[0098] The second aspect of the present invention is to provide a control method for a multi-energy collaborative control cabinet for a smart microgrid, which includes the working logic of the internal modules of the control cabinet, manual and automatic mode selection, local manual control, local automatic control, remote control, synchronous grid-connected permission control, blockchain-based evidence management, and touch screen human-computer interaction.

[0099] The working logic of the internal module of the control cabinet includes the following steps:

[0100] Step 1: After the voltage and current sampling signals of the mains and microgrid are connected to the power sampling interface module, one is connected to the UPS power module and the other is connected to the intelligent control module;

[0101] Step 2: The voltage signal of the UPS power module is converted into the internal power supply of the control cabinet body 1 by the UPS, and then converted into multiple AC and DC power supplies by the power control module to provide working power for the internal modules of the control cabinet body 1;

[0102] Step 3: The power sampling signal of the intelligent control module is used as a monitoring signal of the microgrid operation status, which is used by the microgrid control device 5 to identify the microgrid operation status;

[0103] Step 4: The human-computer interaction module provides manual and automatic control mode settings for the intelligent control module, and can query the microgrid operation status through the intelligent control module;

[0104] Step 5: The intelligent control module works according to the manual and automatic modes set by the human-computer interaction module: When working in the manual control mode, the intelligent control module does not perform any automatic control. At this time, the manual control module can perform multi-circuit circuit breaker opening and closing control operations;

[0105] Step 6: When working in automatic control mode, the intelligent control module identifies different operating conditions of the microgrid according to the changes in the power sampling signal, and then automatically controls the microgrid accordingly. The intelligent control module automatically controls the microgrid accordingly, including real-time monitoring of the energy storage PCS, BMS, photovoltaic inverter, and diesel generator controller through communication module and EMS, and opening and closing control of multi-circuit circuit breakers through internal relay control module.

[0106] The manual automatic control mode selection implementation method includes the following steps:

[0107] Step 1: Select through the manual and automatic mode selection module 4 button SA1. If it is placed in the left gear, the "automatic" status indicator light is on, which is the automatic control state. If it is placed in the right gear, the "manual" status indicator light is on, which is the manual control state;

[0108] Step 2: When SA1 selects the "manual" control mode, relay KA1 is energized, pins 5 and 9 are connected, and a DI signal is generated and input to the microgrid control device 5. At this time, the microgrid control device 5 recognizes that the multi-energy system cabinet enters the "manual" control mode, otherwise it enters the "automatic" control mode;

[0109] Step 3: When SA1 selects the "manual" control mode, the control buttons of all manual opening and closing control modules are connected to the ground, allowing manual opening and closing operations on each circuit breaker;

[0110] Step 4: When SA1 selects the "automatic" control mode, the control buttons of all manual opening and closing control modules are disconnected from the ground, and manual opening and closing operations on each circuit breaker are prohibited;

[0111] Step 5: Whether you select the "manual" or "automatic" control mode, the circuit breaker's opening and closing status indicator lights will display normally.

[0112] The local manual control method includes the following steps:

[0113] Step 1: In the "manual" control mode, press the SB closing button of the circuit breaker (PCC circuit breaker, energy storage PCS short circuit breaker or photovoltaic circuit breaker). If the closing is successful, the closing status indicator of the corresponding circuit breaker will light up, and the manual closing operation of the circuit breaker is completed;

[0114] Step 2: In the "manual" control mode, press the SB opening button of the circuit breaker (PCC circuit breaker, energy storage PCS short circuit breaker or photovoltaic circuit breaker). If the opening is successful, the opening status indicator of the corresponding circuit breaker will light up, and the manual opening operation of the circuit breaker is completed;

[0115] Step 3: The relay control module finally reports the operation information and feedback information to the microgrid control device 5 through the DDC controller 15, and further reports to the EMS energy management system to realize the action and status monitoring and recording of manual operation.

[0116] The local automatic control method comprises the following steps:

[0117] Step 1: The microgrid control device 5 monitors the change of the control mode, and the default is the automatic operation mode;

[0118] Step 2: In the local automatic control mode, if the "manual" control mode is detected, the automatic mode will be exited and the manual mode will be entered. If the remote control mode is detected, the automatic mode will be exited and the remote mode will be entered. The local manual control mode has the highest level, the remote control level is the second, and the local automatic control level is the lowest.

[0119] Step 3: Under local automatic control, when the mains power is suddenly cut off during grid-connected operation, the microgrid control device 5 promptly controls to cut off the mains power sampling signal of the energy storage PCS, controls the grid-connected circuit breaker of the PCC point, and cuts off the corresponding non-important load circuit breakers or limit photovoltaic power generation according to the priority according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to the island operation state;

[0120] Step 4: Under local automatic control, when the PCC point is monitored for reverse power and the energy storage is allowed to charge, the microgrid control device 5 controls the energy storage battery to charge. When there is still surplus after full charge, if access to the Internet is allowed, the reverse power is measured, otherwise the photovoltaic power is controlled to limit power generation;

[0121] Step 5: During grid-connected operation, when the energy storage battery reaches the deep charge and deep discharge setting time, the microgrid control device 5 controls the energy storage battery to perform deep charge and deep discharge maintenance operations;

[0122] Step 6: During island operation, when the monitored mains power is restored and the set grid-connection delay time parameter is reached, the microgrid control device 5 promptly controls the connection of the energy storage PCS mains power sampling signal, and controls the closing PCC point grid-connected circuit breaker when the energy storage PCS automatically synchronizes and issues a grid-connection instruction, and connects the corresponding non-important load circuit breaker or restores photovoltaic power generation according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to grid-connected operation;

[0123] Step 7: During island operation, when the monitored microgrid power generation is greater than the load and the energy storage is full, the microgrid control device 5 controls the photovoltaic power generation to be limited. Conversely, if the energy storage SOC is insufficient, the microgrid control device 5 cuts off non-important loads according to priority or starts the diesel generator to supplement energy.

[0124] The remote control method includes the following steps:

[0125] Step 1: The microgrid control device 5 monitors the change of the control mode, and the default is the automatic operation mode;

[0126] Step 2: In the automatic operation mode, if the remote control mode is detected, exit the automatic mode and enter the remote mode;

[0127] Step 3: In the remote control mode, when the EMS planned grid-connection to islanding instruction is detected, the microgrid control device 5 promptly controls the cutting off of the energy storage PCS mains sampling signal, controls the PCC point grid-connected circuit breaker, and cuts off the corresponding non-important load circuit breaker or the limited photovoltaic power generation power according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to the islanding operation state;

[0128] Step 4: When connected to the grid in remote control mode, the microgrid control device 5 controls the energy storage PCS, photovoltaic inverter, diesel generator controller, and remote opening and closing of the circuit breaker according to the instructions issued by the EMS;

[0129] Step 5: When operating in an isolated island mode in remote control mode, after monitoring the mains power recovery and receiving the EMS isolated grid-connected command, the microgrid control device 5 promptly controls the connection of the energy storage PCS mains power sampling signal, waits until the energy storage PCS automatically synchronizes and issues a grid-connected instruction, and controls the closing PCC point grid-connected circuit breaker, and connects the corresponding non-important load circuit breaker or restores photovoltaic power generation according to the internal energy balance of the microgrid; at that time, the energy storage PCS automatically switches to grid-connected operation;

[0130] Step 6: When operating in an isolated island mode in remote control mode, the microgrid control device 5 controls the energy storage PCS, photovoltaic inverter, diesel generator controller, and remote opening and closing of the circuit breaker according to the instructions issued by the EMS.

[0131] The synchronous grid connection permission control method comprises the following steps:

[0132] Step 1: When there is no voltage in the microgrid, the synchronous grid connection permission status indicator lights up, allowing the PCC point circuit breaker closing operation in local automatic control mode, local manual control mode and remote control mode;

[0133] Step 2: When the microgrid PQ is connected to the grid, the synchronous grid connection permission status indicator lights up, allowing the PCC point circuit breaker closing operation in local automatic control mode, local manual control mode or remote control mode;

[0134] Step 3: When the microgrid VF / VSG island is running, the synchronous grid connection permission status indicator light will be on only when the microgrid control device 5 detects that the phase, frequency and voltage between the microgrid and the mains reach the quasi-synchronous grid connection permission conditions after quasi-synchronous adjustment. Otherwise, the PCC point circuit breaker closing operation is prohibited in any control mode. Quasi-synchronous adjustment includes three methods: VSG mode external remote adjustment, VF mode automatic phase locking and shutdown switching grid connection.

[0135] The VSG mode external remote adjustment method for quasi-synchronization comprises the following steps:

[0136] Step 1: When it is necessary to transfer from an isolated grid to a grid-connected grid, if the main energy storage PCS has the external remote adjustment function of the VSG mode, the microgrid control device 5 remotely adjusts the frequency and phase of the microgrid main energy storage PCS through the PDI method, and then adjusts the voltage through the PID remote reactive method;

[0137] Step 2: When the frequency, phase and voltage of the microgrid are monitored to meet the quasi-synchronous grid-connected conditions, the microgrid control device 5 controls the closing permission status indicator to light up, and automatically controls the PCC point circuit breaker to close, completing the quasi-synchronous grid-connected closing;

[0138] Step 3: When the switch is closed successfully, the microgrid control device 5 controls the energy storage PCS mains sampling power supply line;

[0139] Step 4: The energy storage PCS automatically disconnects from the grid and shuts down after detecting that the city power is restored;

[0140] Step 5: The microgrid control device 5 controls the energy storage PCS to start the energy storage PCS grid-connected operation in PQ mode to achieve quasi-synchronous grid connection;

[0141] The VF mode automatic phase-locked quasi-synchronous adjustment method comprises the following steps:

[0142] Step 1: When it is necessary to transfer from an isolated grid to a grid-connected grid, if the main energy storage PCS has a VF automatic phase-locked synchronous grid-connected function, the microgrid control device 5 controls and connects the energy storage PCS mains sampling power supply line;

[0143] Step 2: After the energy storage PCS detects that the mains sampling signal is restored, it automatically locks the phase and synchronizes. When the synchronization conditions are met, it notifies the microgrid control device 5 to allow synchronous grid connection;

[0144] Step 3: After receiving the quasi-synchronous synchronization permission closing signal, the microgrid control device 5 controls the closing permission status indicator to light up, and automatically controls the PCC point circuit breaker to close, completing the quasi-synchronous grid-connected closing;

[0145] The shutdown switching and grid-connection method comprises the following steps:

[0146] Step 1: When it is necessary to transfer from an isolated grid to a grid-connected grid, if the main energy storage PCS does not have a quasi-synchronous regulation function, the microgrid control device 5 directly controls the main energy storage PCS to shut down;

[0147] Step 2: When the energy storage PCS is shut down and the microgrid is out of power for more than 1 second, the microgrid control device 5 controls the PCC grid connection point circuit breaker to close;

[0148] Step 3: After the closing is successful, when it is monitored that the microgrid has restored power supply, the microgrid control device 5 controls the energy storage PCS to restart in the PQ grid-connected mode, and completes the island-to-grid operation after successful startup.

[0149] The touch screen human-computer interaction method comprises the following steps:

[0150] Step 1: The touch screen 2 is a capacitive touch screen, which is connected to the microgrid control device 5 via RS485;

[0151] Step 2: Touch screen 2 mainly displays the operation configuration of the microgrid, the main monitoring and metering data of the mains and microgrid, and important alarm information;

[0152] Step 3: By switching pages, you can query multiple pages of information and the operating parameters issued by EMS.

[0153] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A multi-energy collaborative control cabinet for a smart microgrid, comprising a control cabinet body (1), characterized in that: The control cabinet body (1) is internally installed with a human-machine interaction module, an intelligent control module, a manual control module (7), an internal relay control module, a communication module (9), a power supply control module, a power supply sampling interface module, a circuit breaker control interface module (14) and a UPS power supply module, wherein: The human-machine interaction module comprises a touch screen (2), a grid-connection closing permission status indicator light (3) and a manual-automatic mode selection module (4); The intelligent control module comprises a microgrid control device (5) and an NTP&PTP clock service module (6); The internal relay control module comprises a relay logic control module (8) and a DDC controller (15); The power control module comprises a power socket (10), a surge protector (11), a power air switch (16), a fuse (17), a direct current power supply (18) and a power extension terminal (19); The power sampling module comprises a mains power sampling interface (12) and a microgrid power sampling interface (13); The UPS power supply module comprises a UPS power supply (21) and a storage battery (22).

2. The multi-energy collaborative control cabinet for a smart microgrid according to claim 1 is characterized in that: The touch screen (2) is connected to the microgrid control device (5) via RS485.

3. The multi-energy collaborative control cabinet for a smart microgrid according to claim 1 is characterized in that: The microgrid control device (5) is connected to an external EMS management system, an energy storage PCS and a BMS, a photovoltaic inverter and a diesel generator controller via a communication module (9); the microgrid control device (5) is connected to an external mains power supply and a microgrid power supply line via a power sampling interface module; the microgrid control device (5) controls a multi-circuit circuit breaker via a circuit breaker control interface module (14); The multi-circuit circuit breaker includes a microgrid grid-connected point circuit breaker, a photovoltaic grid-connected circuit breaker, an energy storage grid-connected circuit breaker, a diesel generator grid-connected circuit breaker and a load circuit breaker.

4. The multi-energy collaborative control cabinet for a smart microgrid according to claim 1 is characterized in that: The NTP&PTP clock service module (6) provides a unified clock timing service for the control cabinet body (1) through the communication module (9).

5. The multi-energy collaborative control cabinet for a smart microgrid according to claim 1 is characterized in that: The manual control module (7) manually controls the opening and closing of the multi-circuit circuit breaker through the internal relay control module and the circuit breaker control interface module (14).

6. The multi-energy collaborative control cabinet for a smart microgrid according to claim 1 is characterized in that: The internal relay control module is controlled by a relay logic control module (8) and a DDC controller (15).

7. The multi-energy collaborative control cabinet for a smart microgrid according to claim 1 is characterized in that: The communication module (9) comprises a three-layer network switch and an Ethernet interface, an RS485 interface, a CAN interface, and an AUTBUS / LONWORKS interface.

8. A control method for a multi-energy cooperative control cabinet for a smart microgrid according to any one of claims 1 to 7, characterized in that: The control method includes the working logic of the internal module of the control cabinet, manual and automatic mode selection, local manual control, local automatic control, remote control, synchronous grid-connected permission control, blockchain-based evidence management and touch screen human-computer interaction.

9. The control method of the multi-energy cooperative control cabinet for the smart microgrid according to claim 8 is characterized in that: The working logic of the module inside the control cabinet includes the following steps: S1. After the voltage and current sampling signals of the mains and microgrid are connected to the power sampling interface module, one way is connected to the UPS power module and the other way is connected to the intelligent control module; S2. The voltage signal of the UPS power module is converted into the internal power supply of the control cabinet body (1) by the UPS, and converted into multiple AC and DC power supplies for the internal modules of the control cabinet body (1) through the power control module; S3. The power sampling signal of the access intelligent control module is used as a monitoring signal of the microgrid operation status, and is used for the microgrid control device (5) to identify the microgrid operation condition; S4. The human-computer interaction module provides manual and automatic control mode settings for the intelligent control module, and can query the microgrid operating status through the intelligent control module; S5. The intelligent control module works according to the manual and automatic modes set by the human-machine interaction module: when working in the manual control mode, the intelligent control module does not perform any automatic control, and the manual control module can perform multi-circuit circuit breaker opening and closing control operations; S6. When working in the automatic control mode, the intelligent control module identifies different operating conditions of the microgrid according to the changes in the power sampling signal, and then performs corresponding automatic control on the microgrid.

10. The control method of the multi-energy cooperative control cabinet for the smart microgrid according to claim 9 is characterized in that: The intelligent control module performs corresponding automatic control on the microgrid, including real-time monitoring of the energy storage PCS, BMS, photovoltaic inverter, and diesel generator controller through communication module and EMS, and opening and closing control of multi-circuit circuit breakers through internal relay control module.

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