Micro-grid coordination control system and method

Abstract

The invention discloses a micro-grid coordination control system and method, and relates to the technical field of control, the micro-grid coordination control system comprises a central controller, a management system, a coordination system and an execution system, the central controller is respectively connected with the management system, the coordination system and the execution system; the central controller is used for acquiring the micro-grid operation data sent by the management system and sending the micro-grid operation data to the coordination system, and is used for acquiring a control scheme sent by the coordination system and sending the control scheme to the execution system; the control scheme comprises a control scheme in a grid-connected mode and a control scheme in an off-grid mode; the central controller is also used for sending a grid-connected or off-grid instruction to an execution system based on the operation data of the micro-grid, and controlling the micro-grid to switch between a grid-connected mode and an off-grid mode. The control scheme is executed through the execution system, so that quick response to grid-connected operation and off-grid operation is realized, and impact on the micro-grid is avoided.

Description

Technical Field

[0001] The present invention relates to the field of control technology, and in particular to a microgrid coordinated control system and method. Background Art

[0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art.

[0003] With the development of economy, the demand for electricity is growing rapidly. The power sector has to build more power stations and large-capacity transmission networks, and the scale of the power grid is getting larger and larger. Large power grids not only require large investments, but are also difficult to operate and dispatch, and have higher safety risks. The losses caused by large-scale power outages in the power grid are staggering, and also highlight the vulnerability of large power grids. Microgrids are autonomous systems that can achieve self-control, protection and management. They can be connected to external power grids or operated in isolation. Therefore, microgrids are a strong support for large power grids in the future.

[0004] Usually, a microgrid is connected to an external grid for operation. Both the microgrid and the external grid provide power to the load at the same time. If the external grid fails, the microgrid needs to switch to off-grid operation. When the external grid resumes operation, it needs to switch back to grid-connected operation. If the microgrid cannot respond quickly during the switching process between on-grid and off-grid, it is easy to cause an impact on the microgrid, and the stability and reliability of power supply cannot be guaranteed. However, the existing control method takes a long time to detect off-grid operation, which easily affects the microgrid's ability to respond quickly during the switching process between on-grid and off-grid. Summary of the invention

[0005] In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a microgrid coordinated control system and method, which can quickly respond to grid-connected operation and off-grid operation, thereby helping to avoid impact on the microgrid.

[0006] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0007] In a first aspect, the present invention provides a microgrid coordinated control system, wherein the microgrid includes an energy storage unit, a power generation unit and a load, and the microgrid coordinated control system includes a central controller, a management system, a coordination system and an execution system, wherein the central controller is connected to the management system, the coordination system and the execution system respectively;

[0008] The management system is used to collect microgrid operation data in real time and send it to the central controller;

[0009] The coordination system is used to generate a control scheme based on the acquired microgrid operation data and send it to the central controller;

[0010] The execution system is used to execute corresponding control operations according to the control scheme when acquiring the control scheme sent by the central controller;

[0011] The central controller is used to obtain the microgrid operation data sent by the management system and send it to the coordination system, and to obtain the control scheme sent by the coordination system and send it to the execution system;

[0012] The control scheme includes control schemes in grid-connected mode and off-grid mode; the central controller is also used to send grid-connected or off-grid instructions to the execution system based on the microgrid operation data to control the microgrid to switch between grid-connected mode and off-grid mode.

[0013] According to a further technical solution, the management system includes a human-computer interaction module, an energy storage detection module, a load power detection module, an external power grid power detection module and a power generation unit output power detection module, and the above modules are all connected to the central controller;

[0014] The human-computer interaction module is used to pre-input the rated power of the power generation unit, the maximum variable output power of the power generation unit, the minimum variable output power of the power generation unit and the maximum storage energy of the energy storage unit; the energy storage detection module is used to detect the actual storage energy of the energy storage unit; the load power detection module is used to detect the actual load power; the external power grid power detection module is used to detect the actual power grid power of the external power grid; the power generation unit output power detection module is used to detect the actual output power of the power generation unit.

[0015] According to a further technical solution, the coordination system includes a scheme generation module and an update module, both of which are connected to the central controller; the scheme generation module is used to generate a control scheme based on the acquired microgrid operation data; the update module is used to update the rated output power of the power generation unit;

[0016] The coordination system also includes a frequency and voltage regulation module connected to the central controller, which is used to control the stability of the frequency and voltage of the microgrid.

[0017] According to a further technical solution, the execution system includes a switching module, which is connected to the central controller and is used to control the microgrid to switch between a grid-connected mode and an off-grid mode.

[0018] A further technical solution also includes a topology generation module, which is connected to the central controller and is used to generate a microgrid topology map and send it to the central controller.

[0019] A further technical solution also includes a wireless communication module, which is connected to the central controller and is used to achieve wireless communication between the central controller and the remote monitoring center.

[0020] According to a further technical solution, the central controller sends the acquired microgrid operation data and microgrid topology map to a remote monitoring center via a wireless communication module.

[0021] In a second aspect, the present invention provides a microgrid coordinated control method, comprising:

[0022] Collect microgrid operation data in real time;

[0023] Controlling the microgrid to switch between a grid-connected mode and an off-grid mode based on the operation data, and generating a control scheme based on the microgrid operation data;

[0024] Corresponding control operations are performed based on the control scheme to achieve rapid response of microgrid on-grid operation and off-grid operation.

[0025] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in a microgrid coordinated control method as described in the second aspect.

[0026] In a fourth aspect, the present invention provides a computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps in a microgrid coordinated control method as described in the second aspect are implemented.

[0027] One or more of the above technical solutions have the following beneficial effects:

[0028] The present invention collects microgrid operation data through a management system, and a coordination system generates a control scheme based on the operation data; and an execution system executes the control scheme, thereby achieving rapid response to grid-connected operation and off-grid operation, which helps to avoid impact on the microgrid.

[0029] The present invention calculates the control error and the error change rate by detecting the actual output power of the power generation unit under the rated output power, generates a power output curve based on the control error and the error change rate to solve the actual rated output power, and updates the input rated output power according to the actual rated power, thereby helping to avoid damage to the microgrid caused by inaccurate rated power output due to performance degradation caused by long-term use of the power generation unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0031] Figure 1is a system architecture diagram of a coordinated control system according to an embodiment of the present invention;

[0032] Figure 2 It is a flow chart of a coordinated control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0035] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0036] Embodiment 1

[0037] like Figure 1 As shown, this embodiment discloses a microgrid coordinated control system, the microgrid includes an energy storage unit, a power generation unit and a load, the microgrid coordinated control system includes a central controller, a management system, a coordination system and an execution system, and the central controller is connected to the management system, the coordination system and the execution system respectively.

[0038] The management system is used to collect microgrid operation data in real time and send it to the central controller.

[0039] The coordination system is used to generate a control scheme based on the acquired microgrid operation data and send it to the central controller.

[0040] The execution system is used to execute corresponding control operations according to the control scheme when acquiring the control scheme sent by the central controller.

[0041] The central controller is used to obtain the microgrid operation data sent by the management system and send it to the coordination system, and is used to obtain the control scheme sent by the coordination system and send it to the execution system.

[0042] The control scheme includes control schemes in grid-connected mode and off-grid mode; the central controller is also used to send grid-connected or off-grid instructions to the execution system based on the microgrid operation data to control the microgrid to switch between grid-connected mode and off-grid mode.

[0043] (I) Management system: The management system includes a human-computer interaction module, an energy storage detection module, a load power detection module, an external power grid power detection module, and a power generation unit output power detection module, all of which are connected to the central controller. The management system collects microgrid operation data through the above modules, that is, the microgrid operation data includes the rated power P of the power generation unit. 额定 , the maximum variable output power P of the power generation unit max , the minimum variable output power of the power generation unit, the maximum storage capacity H of the energy storage unit max , the actual storage capacity of the energy storage unit H 储能 、 Actual load power P 负载 and the actual grid power P 电网 .

[0044] A) Human-computer interaction module, used to input the rated power P of the power generation unit in advance 额定 , the maximum variable output power P of the power generation unit max , the minimum variable output power of the power generation unit and the maximum storage capacity H of the energy storage unit max The human-machine interaction module is connected to the central controller so as to send the pre-input data to the central controller through the human-machine interaction module. The human-machine interaction module can be implemented by a display device, for example, to interact with the operator.

[0045] B) Energy storage detection module, used to detect the actual storage energy H of the energy storage unit 储能 The energy storage detection module also includes a SOC dynamic balancing control module (not shown), which is used to evenly distribute the charging power and discharging power of the electronic group to the SOC of the battery group in the energy storage unit, so as to finally achieve the consistency of the SOC of each battery group. It should be noted that, in this embodiment, the energy storage unit is assembled from multiple battery groups.

[0046] C) Load power detection module, used to detect the actual load power P 负载 .

[0047] D) External grid power detection module, used to detect the actual grid power P provided by the external grid 电网 .

[0048] E) Power generation unit output power detection module, used to detect the actual output power P of the power generation unit when it works at the rated output power 实际 .

[0049] (ii) Coordination system: The coordination system includes a scheme generation module, an update module and a frequency and voltage regulation module, all of which are connected to the central controller.

[0050] A) A scheme generation module is used to generate a control scheme based on the acquired microgrid operation data, that is, based on the preset rated power P of the power generation unit. 额定 , the maximum variable output power P of the preset power generation unit max , the preset minimum variable output power of the power generation unit, the actual grid power P of the external grid 电网 、 Actual load power P 负载 、The maximum storage capacity of the energy storage unit H max , the actual storage capacity of the energy storage unit H 储能 , the actual output power P when the power generation unit works at rated output power 实际 , to generate control schemes.

[0051] It should be noted that the preset maximum variable output power P of the power generation unit max The minimum variable output power of the preset power generation unit is set based on the rated power. Each power generation unit has a variable output power range within the upper and lower range of its rated power. This is well known to those skilled in the art and will not be elaborated on again.

[0052] Among them, the control scheme includes the control scheme in the grid-connected mode and the control scheme in the off-grid mode. The control scheme logic generated by the scheme generation module is as follows:

[0053] (1) In grid-connected mode:

[0054] If the actual power grid power P 电网 Greater than the actual load power P 负载 And the storage capacity of the energy storage unit H 储能 Less than the maximum storage capacity H of the energy storage unit max When the power generation unit (such as a generator device) is controlled not to work, the external power grid charges the energy storage unit.

[0055] If the actual power grid power P 电网 Less than the actual load power P 负载 , but the actual grid power P of the external grid 电网 and the rated output power P of the generating unit 额定 The sum is greater than the actual load power P 负载 And the storage capacity of the energy storage unit H 储能 Less than the maximum storage capacity H of the energy storage unit max When the energy storage unit reaches the maximum storage capacity H maxWhen the actual output power of the power generation unit is controlled (for example, the power generation unit is operated at an output power less than the rated output power but greater than or equal to the minimum variable output power), the actual power grid power P of the external power grid is minimized. 电网 and the rated output power P of the generating unit 额定 The sum is equal to the actual load power P 负载 .

[0056] For example, if the power generation unit outputs the minimum variable power and the actual power grid power P 电网 The sum is still greater than the actual load power P 负载 , the power generation unit is controlled to operate at the minimum variable output power.

[0057] If the actual power grid power P 电网 and the maximum variable output power P of the power generation unit max The sum is less than the actual load power P 负载 , then the power generation unit is controlled to work at the maximum variable output power and the energy storage unit is controlled to output power P 储能 , so that the actual grid power P of the external grid 电网 , the maximum variable output power P of the power generation unit max And the output power P of the energy storage unit 储能 The sum of the three is not less than the actual load power P 负载 .

[0058] (2) In off-grid mode:

[0059] If the minimum variable output power of the generating unit is greater than the actual load power P 负载 When , the power generation unit is controlled to operate at the minimum variable output power.

[0060] If the power generation unit is at the maximum variable output power P max Less than the actual load power P 负载 When the power generation unit is controlled to output the maximum variable power P max Work and control the output power P of the energy storage unit 储能 , so that the power generation unit has the maximum variable output power P max The actual output power P 实际 And the energy storage unit output power P 储能 The sum is not less than the actual load power P 负载 .

[0061] If the rated output power of the generating unit is P 额定 Less than the actual load power P 负载 , and the maximum variable output power P of the power generation unit max Greater than the actual load power P 负载When the power generation unit is controlled, the actual output power P 实际 Equal to the actual load power P 负载 Works at output power.

[0062] B) An updating module, which is used to update the rated output power of the power generation unit. The updating module includes a calculation module and a power output curve module which are interconnected. The calculation module is used to update the rated output power P according to the input 额定 And the actual output power P at rated output power 实际 Calculate the power generation unit control error and error change rate and send them to the power output curve module. The calculation formula is as follows:

[0063] E(t)=P 额定 (t)-P 实际 (t)

[0064] DE(t)=E(t)-E(t-1)

[0065] Where E(t) is the control error, DE(t) is the error change rate, and t and t-1 represent time.

[0066] The power output curve module is used to obtain the control error and error change rate of the power generation unit, to generate the output power curve of the power generation unit based on the control error and error change rate, and to solve the actual rated output power based on the power output curve. The solved actual rated power is sent to the central controller, and the central controller updates the pre-input rated output power of the power generation unit according to the solved actual rated power, thereby avoiding damage to the microgrid caused by inaccurate rated power output due to performance degradation caused by long-term use of the power generation unit.

[0067] It should be noted that, due to the preset maximum variable output power P of the power generation unit max The minimum variable output power of the preset power generation unit is set based on the rated power. Therefore, when the rated output power of the power generation unit is updated, the maximum variable output power P of the power generation unit is also updated. max The minimum variable output power of the power generation unit will also be updated accordingly.

[0068] C) The frequency and voltage regulation module is connected to the central controller and is used to control the frequency and voltage of the microgrid to be stable and without deviation when the switching module switches between the grid-connected mode and the off-grid mode, thereby realizing seamless switching between the grid-connected mode and the off-grid mode.

[0069] (III) Execution system: The execution system is used to execute corresponding control operations according to the control scheme when the control scheme sent by the central controller is obtained.

[0070] The execution system includes a switching module, which is connected to the central controller and is used to control the microgrid to switch between the grid-connected mode and the off-grid mode based on the control scheme generated by the coordination system. The grid-connected mode refers to the external grid being connected to the microgrid to supply power to the loads in the microgrid, and the off-grid mode refers to the external grid not being connected to the microgrid.

[0071] (IV) Topology generation module: The topology generation module is connected to the central controller and is used to generate a microgrid topology map and send it to the central controller. The central controller displays the received microgrid topology map through the human-computer interaction module. Specifically, the topology map generation module generates a topology map based on the location and connection relationship of the power generation unit, energy storage unit and load in the microgrid, and sends the generated microgrid topology map to the central processor for display on the human-computer interaction interface (human-computer interaction module). At the same time, the topology map also displays the working status of each unit in the microgrid.

[0072] (V) Wireless communication module: The wireless communication module is connected to the central controller and is used to realize wireless communication between the central controller and the remote monitoring center. The central controller sends the acquired microgrid operation data and microgrid topology map to the remote monitoring center for monitoring through the wireless communication module. For example, the detected power P of the external power grid 电网 And other data.

[0073] (VI) Central controller: The central controller is connected to the management system to obtain the microgrid operation data sent by the management system. Based on the actual grid power P in the operation data 电网 The grid-connection or off-grid instruction is sent to the execution system (i.e., the switching module), so that the switching module controls the system to switch between the grid-connection mode and the off-grid mode based on the received grid-connection or off-grid instruction. For example, the actual grid power P detected is 电网 If it is 0, an off-grid instruction is sent to the switching module, so that the switching module controls the system to switch to the off-grid mode based on the received off-grid instruction.

[0074] Embodiment 2

[0075] This embodiment provides a microgrid coordinated control method, involving a central controller, a management system, a coordination system and an execution system, wherein the central controller is connected to the management system, the coordination system and the execution system respectively, and includes the following steps:

[0076] S1: real-time collection of microgrid operation data;

[0077] S2: Controlling the microgrid to switch between a grid-connected mode and an off-grid mode based on the operation data, and generating a control scheme based on the microgrid operation data;

[0078] S3: Execute corresponding control operations based on the control scheme to achieve rapid response of microgrid on-grid operation and off-grid operation.

[0079] Embodiment 3

[0080] The purpose of this embodiment is to provide a computing device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method of Embodiment 2 when executing the program.

[0081] Embodiment 4

[0082] The purpose of this embodiment is to provide a computer-readable storage medium, a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the steps of the method of embodiment 2 are performed.

[0083] The steps involved in the apparatus of the above embodiments 3 and 4 correspond to the method embodiment 1, and the specific implementation method can refer to the relevant description part of embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood to include any medium that can store, encode or carry an instruction set for execution by a processor and enable the processor to execute any method in the present invention.

[0084] Those skilled in the art should understand that the modules or steps of the present invention described above can be implemented by a general-purpose computer device, or alternatively, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0085] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0086] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A microgrid coordinated control system, the microgrid comprising an energy storage unit, a power generation unit and a load, characterized in that: The microgrid coordinated control system includes a central controller, a management system, a coordination system and an execution system, and the central controller is connected to the management system, the coordination system and the execution system respectively; The management system is used to collect microgrid operation data in real time and send it to the central controller; The coordination system is used to generate a control scheme based on the acquired microgrid operation data and send it to the central controller; The execution system is used to execute corresponding control operations according to the control scheme when acquiring the control scheme sent by the central controller; The central controller is used to obtain the microgrid operation data sent by the management system and send it to the coordination system, and to obtain the control scheme sent by the coordination system and send it to the execution system; The control scheme includes control schemes in grid-connected mode and off-grid mode; the central controller is also used to send grid-connected or off-grid instructions to the execution system based on the microgrid operation data to control the microgrid to switch between grid-connected mode and off-grid mode.

2. A microgrid coordinated control system as claimed in claim 1, characterized in that: The management system includes a human-computer interaction module, an energy storage detection module, a load power detection module, an external power grid power detection module and a power generation unit output power detection module, and the above modules are all connected to the central controller; The human-computer interaction module is used to pre-input the rated power of the power generation unit, the maximum variable output power of the power generation unit, the minimum variable output power of the power generation unit and the maximum storage energy of the energy storage unit; the energy storage detection module is used to detect the actual storage energy of the energy storage unit; the load power detection module is used to detect the actual load power; the external power grid power detection module is used to detect the actual power grid power of the external power grid; the power generation unit output power detection module is used to detect the actual output power of the power generation unit.

3. A microgrid coordinated control system as claimed in claim 1, characterized in that: The coordination system includes a scheme generation module and an update module, both of which are connected to the central controller; the scheme generation module is used to generate a control scheme based on the acquired microgrid operation data; the update module is used to update the rated output power of the power generation unit; The coordination system also includes a frequency and voltage regulation module connected to the central controller, which is used to control the stability of the frequency and voltage of the microgrid.

4. A microgrid coordinated control system as claimed in claim 1, characterized in that: The execution system includes a switching module, which is connected to the central controller and is used to control the microgrid to switch between a grid-connected mode and an off-grid mode.

5. A microgrid coordinated control system as claimed in claim 1, characterized in that: It also includes a topology generation module, which is connected to the central controller and is used to generate a microgrid topology map and send it to the central controller.

6. A microgrid coordinated control system as claimed in claim 1, characterized in that: It also includes a wireless communication module, which is connected to the central controller and is used to achieve wireless communication between the central controller and the remote monitoring center.

7. A microgrid coordinated control system as claimed in claim 6, characterized in that: The central controller sends the acquired microgrid operation data and microgrid topology map to the remote monitoring center through the wireless communication module.

8. A microgrid coordinated control method, characterized in that: include: Collect microgrid operation data in real time; Controlling the microgrid to switch between a grid-connected mode and an off-grid mode based on the operation data, and generating a control scheme based on the microgrid operation data; Corresponding control operations are performed based on the control scheme to achieve rapid response of microgrid on-grid operation and off-grid operation.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps in a microgrid coordinated control method as described in claim 8 are implemented.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps in the microgrid coordinated control method as described in claim 8 are implemented.

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