A micro-grid cluster system based on sufficient autonomous controlled sharing and a control method thereof

Abstract

The application discloses a micro-grid cluster system based on sufficient autonomous controlled sharing and a control method thereof. According to the controlled sharing principle agreed in advance, each micro-grid system autonomously operates under the controlled sharing constraint condition. The application considers safety, economy and rationality, divides 24 hours of each day into multiple operation time periods T, adopts the method that power regulation declaration is uniformly approved and controlled execution is carried out, autonomously executes the interactive power with the power grid according to the approved power and power limit, and realizes autonomous control and operation management through the energy management system (EMS) of each micro-grid system. According to the power regulation instruction of the general energy management system (GEMS) of the micro-grid cluster system, each micro-grid system autonomously interacts with the power bus according to the controlled sharing principle, so that each micro-grid system in the micro-grid cluster can fully autonomously control and operate and autonomously interact with power, and the resource utilization rate of each micro-grid system is improved and the investment benefit is increased.

Description

Technical Field

[0001] This invention belongs to the field of microgrid technology, specifically relating to a microgrid cluster system and control method based on fully autonomous, controlled, and shared systems. Background Technology

[0002] The transformation of the energy structure has promoted the widespread application of new energy sources, especially distributed renewable energy. However, the uncertainty and volatility of distributed renewable energy pose significant challenges to the stable operation of electricity and the power grid. To address this, using local microgrids to connect distributed renewable energy, energy storage, and loads for local balancing and consumption is one effective method for the efficient application of distributed renewable energy. Because distributed renewable energy has a relatively low energy density, it is suitable for decentralized, localized installation and application. For example, building-based solar power systems combined with peak-shaving and valley-filling energy storage can form microgrid systems. Furthermore, different owners and investors invest in and construct distributed renewable energy microgrid systems at different times and locations based on their own conditions. The application of distributed renewable energy microgrid systems is a gradual and developing process, and the phenomenon of building multiple microgrid systems in a single region is beginning to emerge. Therefore, researching the connection of multiple decentralized microgrids to form a microgrid cluster system for overall operation and resource sharing is a development trend in the application of distributed renewable energy. Microgrid cluster system technology is complex and still in its early stages; currently, there is no mature and effective method for constructing and controlling a microgrid cluster system. Summary of the Invention

[0003] To explore effective operation and control methods for microgrid cluster systems, and to achieve reasonable and stable control of the overall operation and resource sharing of multiple dispersed microgrids to form a microgrid cluster system, this invention, based on the main technical characteristics and networking features of microgrids, realizes full autonomy and controlled sharing among individual microgrid systems. Specifically, this invention discloses a microgrid cluster system and control method based on full autonomy and controlled sharing, characterized by:

[0004] Under the agreed-upon sharing principle, each independently operating microgrid system is connected to the same power bus via a controlled switch to form a microgrid cluster system. This mainly includes: the power grid connecting to the power line via a power grid switch; the power line connecting to the first microgrid system, the second microgrid system, the i-th microgrid system, and the n-th microgrid system via a power grid access switch; and the energy management system (GEMS) connecting to the first microgrid system via communication lines. A microgrid cluster system consisting of a control system EMS, a second microgrid control system EMS, an i-th microgrid control system EMS, an n-th microgrid control system EMS, and access switches for the first, second, i-th, and n-th microgrid systems, operating off-grid, is characterized by the following: the microgrid cluster energy management system GEMS is connected to each independently operating microgrid control system EMS via a communication network, and each microgrid system adjusts the surplus and shortage of electrical energy according to the principle of controlled sharing, thereby achieving overall energy balance and stable operation of the microgrid cluster system.

[0005] Its characteristics are as follows: the controlled sharing principle divides each 24-hour day into multiple operating time periods T. In the first operating time period, each microgrid operates independently and autonomously, maintaining zero power adjustment. In the next operating time period, it reaches the time before t. The EMS reports the surplus or shortage of power, i.e., power and quantity, to the GEMS for the next operating time period T(i+1). After statistical calculation, the GEMS determines the actual amount of power adjustment between each microgrid system and notifies each EMS system. Each microgrid executes the determined power adjustment limit and autonomously controls its operation. Where: T≤60 minutes, t≤0.1T.

[0006] Its characteristic is that the power of power transfer between microgrid systems needs to meet the following: the total on-grid power Pg of each microgrid system is equal to the total off-grid power Pd. If they are not equal, the power with the smaller total power shall prevail. The power difference Pgd between the two total power shall be deducted according to the declared ratio. For microgrid system i, the declared total on-grid power Pgi and total off-grid power Pdi shall be reduced by the amount of reduction = Pgi / Pg*Pgd or Pdi / Pd*Pgd.

[0007] The aforementioned microgrid cluster system and control method based on fully autonomous, controlled, and shared systems are characterized in that, when each microgrid autonomously controls and reports the power of adjusted grid-connected power and the power of adjusted grid-connected power should be reported cross-cuttingly for two consecutive operating periods. If the current operating period is for adjusting grid-connected power, the power of adjusted grid-connected power for the next operating period should be reported; conversely, if the current operating period is for adjusting grid-connected power, the power of adjusted grid-connected power for the next operating period should be reported. Furthermore, the cumulative difference between the power of adjusted grid-connected power and the power of adjusted grid-connected power over a 24-hour period should be ≤10%.

[0008] The microgrid cluster system and control method based on fully autonomous, controlled, and shared systems are characterized by the following microgrid cluster operation control process:

[0009] 1) The microgrid cluster energy management system (GEMS) connects to the EMS of each microgrid system to confirm that each microgrid system is operating independently and autonomously and normally.

[0010] 2) Based on the sharing principle, the microgrid cluster energy management system GEMS obtains the amount of power requested by each microgrid system according to the operating time period, calculates and approves the actual amount of power requested and sends instructions to each microgrid.

[0011] 3) The GEMS (Government Energy Management System) monitors the autonomous operation of each microgrid system and the implementation of the controlled sharing principle;

[0012] 4) The microgrid cluster energy management system (GEMS) monitors whether the microgrid system violates the controlled sharing principle. If yes, proceed to step 5); otherwise, proceed to step 8.

[0013] 5) The microgrid cluster energy management system (GEMS) notifies the EMS of microgrid systems that violate the controlled sharing principle, requiring them to immediately correct the violation.

[0014] 6) The microgrid cluster energy management system (GEMS) monitors whether the microgrid system has corrected any violations. If no, proceed to step 7); if yes, proceed to step 8.

[0015] 7) The microgrid cluster energy management system (GEMS) forcibly disconnects the microgrid system from the power grid line through a controlled switch, stopping the microgrid system from accessing the microgrid cluster system in violation of regulations; after completion, proceed to 4).

[0016] 8) The microgrid cluster energy management system (GEMS) monitors and determines whether the next application deadline has arrived. If yes, proceed to step 10; otherwise, proceed to step 3.

[0017] 9) The microgrid cluster energy management system (GEMS) monitors whether the microgrid cluster system is operating abnormally or alarming, and whether it needs to be shut down. If yes, if an alarm or shutdown is detected, execute step 10); otherwise, proceed to step 2.

[0018] 10) The GEMS (Government Energy Management System) controls the microgrid cluster system to execute alarms and shutdowns.

[0019] This invention discloses a fully autonomous, controlled, and shared microgrid cluster system and its control method. Through pre-agreed controlled sharing principles, each microgrid system operates autonomously under controlled sharing constraints. This invention considers safety, economy, and rationality, dividing each 24-hour day into multiple operating time periods T. Each operating time period employs a method of reporting and uniformly approving power regulation and executing it under controlled conditions. Each microgrid system autonomously interacts with the power grid according to approved power and energy limits. Each microgrid system achieves autonomous control and operation management through its own Energy Management System (EMS). Following power regulation commands issued by the microgrid cluster system's central control system (GEMS), each microgrid system autonomously interacts with the power bus according to the controlled sharing principle. This enables each microgrid system in the cluster to fully autonomously regulate and operate, and autonomously interact with energy, improving resource utilization and increasing investment efficiency. Attached Figure Description

[0020] Figure 1 This is a schematic block diagram of a microgrid cluster system based on full autonomy, controlled sharing.

[0021] Figure 2 This is a control flowchart for a microgrid cluster system based on full autonomy, controlled sharing. Detailed Implementation

[0022] As an example, a microgrid cluster system and control method based on fully autonomous controlled sharing are described in conjunction with the accompanying drawings. However, the described embodiments are only a part of the embodiments of the present invention applied to a microgrid cluster system and control method based on fully autonomous controlled sharing, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. The technology and solutions of the present invention are not limited to the content given in this example.

[0023] like Figure 1 As shown, a microgrid cluster system and control method based on fully autonomous, controlled, and shared systems are characterized by:

[0024] Under the agreed-upon sharing principle, each independently operating microgrid system is connected to the same power bus via a controlled switch to form a microgrid cluster system. This mainly includes: the power grid (4) connected to the power grid line (1) via the power grid switch (5); the power grid line (1) connected to the first microgrid system (11) via the first microgrid system access switch (31), to the second microgrid system (12) via the second microgrid system access switch (32), to the i-th microgrid system (1i) via the i-th microgrid system access switch (3i), and to the n-th microgrid system (1n) via the n-th microgrid system access switch (3n). Simultaneously, the microgrid cluster energy management system GEMS (2) is connected via communication lines (6). A microgrid cluster system that is connected to the first microgrid control system EMS (21), the second microgrid control system EMS (22), the i-th microgrid control system EMS (2i), the n-th microgrid control system EMS (2n), and the first microgrid system access switch (31), the second microgrid system access switch (32), the i-th microgrid system access switch (3i), and the n-th microgrid system access switch (3n) and operates off-grid, is characterized by: the microgrid cluster energy management system GEMS (2) is connected to each independently operating microgrid control system EMS through a communication network, and each microgrid system adjusts the surplus and shortage of electrical energy according to the principle of controlled sharing, so as to achieve the overall energy balance and stable operation of the microgrid cluster system.

[0025] The microgrid cluster system and control method based on fully autonomous and controlled sharing are characterized by dividing each 24-hour day into multiple operating time periods T according to the controlled sharing principle. In the first operating time period, each microgrid system operates independently and autonomously, maintaining zero power adjustment. In the next operating time period, the power adjustment surplus and shortage power, i.e., power and quantity, are reported to the microgrid cluster energy management system GEMS (2) through the EMS. After statistical calculation, the microgrid cluster energy management system GEMS (2) determines the actual power adjustment quantity between each microgrid system and notifies each EMS system. Each microgrid system executes the determined power adjustment quantity limit and autonomously controls its operation. Wherein: T≤60 minutes, t≤0.1T.

[0026] The aforementioned microgrid cluster system and control method based on fully autonomous, controlled, and shared power is characterized in that the power for adjusting electrical energy between microgrids needs to meet the following condition: the total on-grid power Pg of each microgrid system equals the total off-grid power Pd. If they are not equal, the power with the smaller total power shall prevail. The power difference Pgd between the two total power shall be reduced according to the declared ratio. For microgrid i, the declared total on-grid power Pgi and total off-grid power Pdi shall be reduced by Pgi / Pg*Pgd or Pdi / Pd*Pgd.

[0027] The aforementioned microgrid cluster system and control method based on fully autonomous, controlled, and shared systems are characterized in that when each microgrid autonomously controls and reports the power of the adjusted grid-connected power and the power of the adjusted grid-connected power should be reported cross-cuttingly in two consecutive operating periods. If the current operating period is for adjusting grid-connected power, the power of the adjusted grid-connected power for the next operating period should be reported; conversely, if the current operating period is for adjusting grid-connected power, the power of the adjusted grid-connected power for the next operating period should be reported. Furthermore, the cumulative difference between the power of the adjusted grid-connected power and the power of the adjusted grid-connected power over a 24-hour period should be ≤10%.

[0028] like Figure 2 As shown, the microgrid cluster system and control method based on fully autonomous, controlled, and shared systems are characterized by the following microgrid cluster operation control process:

[0029] 1) The microgrid cluster energy management system GEMS (2) connects to the EMS of each microgrid system to confirm that each microgrid system is operating independently and autonomously.

[0030] 2) Based on the sharing principle, the microgrid cluster energy management system GEMS(2) obtains the amount of power requested by each microgrid system according to the operating time period, calculates and approves and sends the actual amount of power requested to each microgrid;

[0031] 3) The microgrid cluster energy management system GEMS(2) monitors the autonomous operation of each microgrid system and the implementation of the controlled sharing principle;

[0032] 4) The microgrid cluster energy management system GEMS(2) monitors whether the microgrid system violates the controlled sharing principle. If yes, continue to execute 5); otherwise, execute 8).

[0033] 5) The microgrid cluster energy management system GEMS(2) notifies the EMS of the microgrid system that violates the controlled sharing principle and requires it to immediately correct the violation.

[0034] 6) The microgrid cluster energy management system GEMS(2) monitors whether the microgrid system has corrected the violation. If not, execute 7); if yes, execute 8).

[0035] 7) The microgrid cluster energy management system GEMS (2) forcibly disconnects the microgrid system from the power grid line (1) through a controlled switch, stopping the microgrid system that violates the rules from accessing the microgrid cluster system; after completion, proceed to 3);

[0036] 8) The microgrid cluster energy management system GEMS(2) monitors and determines whether the next reporting time has arrived. If yes, proceed to step 10; otherwise, proceed to step 3.

[0037] 9) The microgrid cluster energy management system GEMS(2) monitors whether the microgrid cluster system is operating abnormally and whether there is an alarm or a need to stop operation. If yes, if an alarm or shutdown is detected, execute 10); otherwise, go to 2).

[0038] 10) The microgrid cluster energy management system GEMS(2) controls the microgrid cluster system to perform alarms and shutdowns.

[0039] This invention discloses a fully autonomous, controlled, and shared microgrid cluster system and its control method. Through pre-agreed controlled sharing principles, each microgrid system operates autonomously under these constraints. Each 24-hour day is divided into multiple operating time periods T. Each operating time period employs a method of reporting and uniformly approving power regulation, autonomously interacting with the power grid according to approved power and energy limits. Each microgrid system achieves autonomous control and operation management through its own Energy Management System (EMS). Following power dispatch instructions issued by the microgrid cluster system's central control system (GEMS), each microgrid system autonomously interacts with the power bus according to the controlled sharing principle. This fully autonomous operation and energy interaction of each microgrid system improves resource utilization and increases investment efficiency.

Claims

1. A micro-grid cluster system based on sufficient autonomous controlled sharing and a control method, characterized in that: under the constraint of the agreed sharing principle, each independently operated micro-grid system is connected to the same power bus through a controlled switch to form a micro-grid cluster system; mainly comprising: a power grid (4) is connected to a power grid power line (1) through a power grid power switch (5), the power grid power line (1) is connected to a first micro-grid system (11) through a first micro-grid system access switch (31), a second micro-grid system (12) through a second micro-grid system access switch (32), an i-th micro-grid system (1i) through an i-th micro-grid system access switch (3i), and an n-th micro-grid system (1n) through an n-th micro-grid system access switch (3n), and a micro-grid cluster energy management system GEMS (2) is connected to a first micro-grid control system EMS (21), a second micro-grid control system EMS (22), an i-th micro-grid control system EMS (2i), an n-th micro-grid control system EMS (2n), a first micro-grid system access switch (31), a second micro-grid system access switch (32), an i-th micro-grid system access switch (3i), and an n-th micro-grid system access switch (3n) through a communication line (6), and the micro-grid cluster system operates off-grid, characterized in that: the micro-grid cluster energy management system GEMS (2) is connected to each independently operated micro-grid control system EMS through a communication network, and each micro-grid system adjusts the surplus and deficiency of power according to the controlled sharing principle to control the overall energy balance and stable operation of the micro-grid cluster system. The controlled sharing principle divides 24 hours of each day into multiple operating time periods T, each micro-grid system independently operates autonomously and maintains a power adjustment of 0 in the first operating time period, and reaches the front t time before the next operating time period T(i+1); the EMS reports the power and power adjustment of the next operating time period T(i+1) to the micro-grid cluster energy management system GEMS (2); the micro-grid cluster energy management system GEMS (2) determines the actual power adjustment amount between each micro-grid system after statistical calculation and notifies each EMS system, and each micro-grid system executes the determined power adjustment limit and autonomously controls operation; wherein: T≤60 minutes, t≤0.1T; The power adjustment between micro-grid systems needs to meet: the total on-grid power Pg of each micro-grid system is equal to the total off-grid power Pd, if they are not equal, the smaller one is used as the reference, and the excess power difference Pgd is reduced according to the reported proportion, the reported on-grid power Pgi and off-grid power Pdi of the micro-grid system i, the reduction amount =Pgi / Pg*Pgd, or the reduction amount =Pdi / Pd*Pgd. ​ 2. The microgrid cluster system and control method based on sufficient autonomy controlled sharing according to claim 1, characterized in that When each micro-grid autonomous control operation declares the power of the regulated power, the power of the regulated on-grid power and the power of the regulated off-grid power should be cross-declared in two consecutive operation periods. If the current operation period is the power of the regulated on-grid power, the next operation period is declared as the power of the regulated off-grid power, and vice versa. The difference between the power of the regulated on-grid power and the power of the regulated off-grid power should be less than or equal to 10% in 24 hours.

3. The microgrid cluster system and control method based on sufficient autonomy controlled sharing according to claim 1, characterized in that the microgrid The cluster operation control process is as follows: 1) The micro-grid cluster energy management and control system GEMS (2) connects the EMS of each micro-grid system and confirms that each micro-grid system is independently and autonomously operating normally; 2) According to the sharing principle, the micro-grid cluster energy management and control system GEMS (2) obtains the declared regulated power quantity of each micro-grid system according to the operation time period, calculates and approves the actual regulated power quantity, and sends the instruction to each micro-grid; 3) The micro-grid cluster energy management and control system GEMS (2) monitors the autonomous operation of each micro-grid system and the status of executing the controlled sharing principle; 4) The micro-grid cluster energy management and control system GEMS (2) monitors whether the micro-grid system violates the controlled sharing principle, and if so, continues to execute 5); otherwise, executes 8); 5) The micro-grid cluster energy management and control system GEMS (2) notifies the EMS of the micro-grid system that violates the controlled sharing principle, requiring it to immediately correct the corresponding violation; 6) The micro-grid cluster energy management and control system GEMS (2) monitors whether the micro-grid system has corrected the violation, and if not, executes 7); Yes, execute 8); 7) The micro-grid cluster energy management and control system GEMS (2) forcibly disconnects the micro-grid system from the power bus through the controlled switch, and stops the micro-grid system from accessing the micro-grid cluster system; after completion, go to 3); 8) The micro-grid cluster energy management and control system GEMS (2) monitors and judges whether it is the next declaration time, yes, go to 10); otherwise, go to 3); 9) The micro-grid cluster energy management and control system GEMS (2) monitors whether the micro-grid cluster system is abnormal and whether it needs to stop running, yes, monitors the alarm and stop running, executes 10); otherwise, go to 2); 10) The micro-grid cluster energy management and control system GEMS (2) controls the micro-grid cluster system to execute the alarm and stop running.

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