Blockchain-based microgrid group distributed intelligent sensing and coordination system

Abstract

The application belongs to the technical field of micro-grid control, and particularly relates to a micro-grid group distributed intelligent sensing and coordinated operation system based on a block chain, which comprises a plurality of micro-grid distributed monitoring units, a plurality of micro-grid distributed intelligent controllers and a block chain; by virtue of the decentralized, trusted and distributed shared database properties of the block chain, each micro-grid distributed intelligent controller node can conveniently obtain various types of operation data shared by other micro-grids in the group from the block chain, intelligently senses the local micro-grid operation state from the perspective of energy interflow in the group in combination with the collected local micro-grid operation data according to the micro-grid operation state intelligent sensing rule library in the block chain intelligent contract, thereby realizing the distributed intelligent sensing of the micro-grid group operation state at each micro-grid distributed intelligent controller node and the intelligent identification of the operation state of the micro-grid.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of micro-grid control, and particularly relates to a micro-grid group distributed intelligent sensing and coordinated operation system based on a block chain. BACKGROUND

[0002] As an effective means of comprehensive utilization of distributed power generation, micro-grid has been widely used with the increasing penetration of renewable energy, and has shown a trend of multi-point dispersion in construction time and space. However, when a single micro-grid operates, it is difficult to ensure full consumption of new energy and safe operation of the system due to the inability to utilize the distributed resources of other micro-grids, making the demand for the coordinated operation of the micro-grid group increasingly urgent. Especially for multiple isolated micro-grids with close electrical distance, the purpose of energy mutual aid and coordinated operation can be achieved through unified regulation by forming a micro-grid group. For the control problem of the micro-grid group, the existing technology usually adopts a three-layer control structure of local unit layer, micro-grid control layer and centralized control center layer in the control system construction. To realize the coordinated operation of each micro-grid in the group, the operation data of each micro-grid collected by the group control center is needed to realize the energy mutual aid regulation between the grids by optimizing the decision to formulate the interactive power plan of each PCC. This control system structure with a group control center is too centralized and compact, and the construction cost is high, which is not conducive to the group coordination operation of multi-point dispersed micro-grids with different construction times and distribution electrical positions. Moreover, the centralized data storage of the group control center has defects such as no redundant backup of data information, high security risk, etc. Once a fault occurs or is attacked by a network, the whole system will face the risk of paralysis. In addition, from the perspective of the micro-grid group regulation strategy formulation method, the existing research is mostly through establishing an optimization regulation model and using a certain optimization algorithm to formulate the regulation strategy, which has problems such as redundant and complex solving process, dimension disaster, low optimization calculation efficiency and easy to fall into local optimal solution, etc., and it is difficult to meet the real-time requirements of the complex working conditions of the micro-grid group operation.

[0003] As a new emerging underlying distributed database technology, the block chain technology provides a new idea for the coordinated operation of multi-point dispersed micro-grids with its characteristics of decentralization, distributed data sharing, security and credibility and programmable smart contract. In fact, each micro-grid of multi-point dispersion has a centralized controller and other devices for local control of distributed units. If the controller can be fully utilized as a distributed control terminal and the decentralized distributed information sharing technology of the block chain is used to realize the distributed coordinated control of multiple micro-grids, it will become an efficient and practical scheme for the coordinated operation of the multi-point dispersed micro-grid group, and will have broad application prospects. However, there is no intelligent sensing and coordinated operation system combining the block chain and micro-grid control. SUMMARY

[0004] In order to solve the above problems, the application provides a micro-grid group distributed intelligent sensing and coordinated operation system based on a blockchain, and the specific technical solutions are as follows.

[0005] A micro-grid group distributed intelligent sensing and coordinated operation system based on a blockchain comprises a plurality of micro-grid distributed monitoring units, a plurality of micro-grid distributed intelligent controllers, and a blockchain.

[0006] The plurality of micro-grid distributed monitoring units are connected with the plurality of micro-grid distributed intelligent controllers respectively, and the plurality of micro-grid distributed intelligent controllers are connected with the blockchain respectively.

[0007] The micro-grid distributed monitoring unit is used for monitoring and collecting the operation data of the renewable energy unit, energy storage unit and load unit of the micro-grid in place, and uploading the collected operation data of the renewable energy unit, energy storage unit and load unit to the micro-grid distributed intelligent controller of the corresponding micro-grid.

[0008] The blockchain is used for storing the operation data of the current period of each micro-grid, intelligent contract and regulation and control plan of each micro-grid in the next period.

[0009] The micro-grid distributed intelligent controller is used for downloading the intelligent contract stored in any block of the blockchain and the operation data of other micro-grids in the micro-grid group required for the micro-grid group state sensing, and combining the operation data monitored and collected by the micro-grid distributed monitoring unit of the micro-grid, based on the micro-grid operation state intelligent sensing rule library in the intelligent contract, performing the local micro-grid operation state intelligent sensing based on the energy mutual aid in the micro-grid group, and then according to the sensed micro-grid operation state, based on the regulation and control strategy knowledge base in the intelligent contract, completing the formulation of the regulation and control plan of the next period of the micro-grid, and issuing the regulation and control instruction to the corresponding micro-grid distributed monitoring unit for execution.

[0010] Preferably, each micro-grid is provided with a to-be-blocked data collection area, which is connected with the micro-grid distributed monitoring unit and the micro-grid distributed intelligent controller of the micro-grid respectively, and is used for storing the current period operation data of the renewable energy unit, energy storage unit and load unit of the micro-grid monitored and collected by the micro-grid distributed monitoring unit.

[0011] Preferably, the microgrid distributed smart controller continuously packages the current operating data of the microgrid, smart contracts, and the generated control plan data for the next period of the microgrid from the data collection area to be formed into a block of the blockchain. Through the blockchain block-producing right competition method based on consensus and reward and punishment mechanism, the newly generated block is shared on the chain so that all microgrid distributed smart controllers can download the required data information.

[0012] Preferably, the smart contract includes a rule base for intelligent sensing of the microgrid's operating status and a knowledge base for formulating control strategies under various operating conditions;

[0013] The current time period operation data refers to the current time period operation data of the renewable energy / energy storage units / load units of this microgrid collected by the microgrid distributed intelligent controller; the control plan for the next time period includes the intelligent sensing microgrid group status, microgrid operation status, PCC interactive power plan for the next time period of this microgrid, energy storage charging and discharging power plan for the next time period of this microgrid, and controllable load control plan for the next time period of this microgrid.

[0014] Preferably, the blockchain block-producing right competition method is as follows:

[0015] Each microgrid distributed smart controller node packages and generates new blocks according to the blockchain data structure, and competes for the right to produce blocks using the PoP consensus mechanism.

[0016] The microgrid distributed smart controller node that successfully obtains the right to produce a block will link the new block to the blockchain in sequence. Linking requires consensus approval from all microgrid distributed smart controller nodes. If approved, the new block is successfully produced and uploaded to the blockchain, and the node receives a reward to gain a competitive advantage in producing blocks in the next cycle. Otherwise, the new block is invalidated, and the node is penalized, reducing its probability of producing a block in the next cycle. The node that successfully produces a block exits the competition for this cycle. The blockchain adjusts the consensus difficulty coefficient to ensure that every microgrid distributed smart controller node can successfully produce and upload a block. Then, the remaining microgrid distributed smart controller nodes in the group compete again to produce and upload blocks according to the above process until all microgrid distributed smart controller nodes successfully upload their new blocks. This completes the sharing of microgrid group data information on the blockchain for this cycle.

[0017] Preferably, the PoP consensus mechanism specifically combines the microgrid PCC interaction power and the energy storage state of charge (SOC) value, that is, each distributed intelligent controller node competes for the block-producing right through the following formula (1):

[0018]

[0019] In the formula: Hash(·) is the hash encryption algorithm; N is a random number; H is the other data in the block header besides N, including the version number, the hash value of the previous block header, the generation timestamp of the current block, and the Merkle root hash value; || represents the concatenation between data; Target represents the target difficulty threshold for hash encryption, the smaller the threshold, the harder it is to find a random value that meets the conditions; a and b are consensus difficulty adjustment coefficients, which are automatically adjusted by the blockchain according to the progress of the block production right competition; P PCCi PCC interactive power of microgrid i; SOC i This represents the energy storage state of charge of microgrid i.

[0020] Preferably, the data required by the microgrid distributed intelligent controller for microgrid group and microgrid status perception includes the data of each microgrid PCC during the current time period. i Switch status, group PCC0 switch status, power generation of each renewable energy source in each microgrid, state of charge (SOC) of each energy storage unit in each microgrid, and power consumption of each load unit in each microgrid.

[0021] Preferably, the microgrid distributed intelligent controller performs microgrid group state perception specifically based on the microgrid group PCC0 switch and the PCC of each microgrid. i The formula for determining and recognizing the open / closed state of a switch is as follows:

[0022]

[0023] In the formula: n is the number of microgrids contained in the microgrid group; PCC i PCC0 represents the PCC switching state of microgrid i; PCC0 represents the PCC switching state of the microgrid group, with 0 indicating off and 1 indicating on.

[0024] Preferably, the steps for the microgrid distributed intelligent controller to perceive the microgrid's operating status are as follows:

[0025] Step S1: Determine whether the microgrid group is in grid-connected or off-grid state, and further determine whether all microgrids within the microgrid group are in parallel or partially in parallel state; if the microgrid group is in grid-connected state and all microgrids are operating in parallel, proceed to step S2; if the microgrid group is in off-grid state and all microgrids are operating in parallel, proceed to step S3; if the microgrid group is in grid-connected state and some microgrids are operating in parallel, or if the microgrid group is in off-grid state and some microgrids are operating in parallel, proceed to step S4.

[0026] Step S2: Sequentially determine whether the total power generation and total power consumption within the microgrid group are balanced, whether the total power generation and total power consumption within each microgrid are balanced, and the energy storage charge status of the microgrid is determined, so as to further perceive the specific status of all microgrids operating in parallel under the grid-connected state of the microgrid group;

[0027] Step S3: Sequentially determine whether the total power generation and total power consumption within the microgrid group are balanced, whether the total power generation and total power consumption within each microgrid are balanced, whether the energy storage of the microgrid is the group master energy storage, and the energy storage charge status of the microgrid, so as to further perceive the specific status of all microgrids operating in parallel under the off-grid state of the microgrid group;

[0028] Step S4: Sequentially determine whether the total power generation and total power consumption in each microgrid are balanced, determine the energy storage charge status of the microgrid, and further perceive the specific status of the microgrid group: whether the microgrids are partially operating in parallel under grid-connected conditions or partially operating in parallel under off-grid conditions.

[0029] The beneficial effects of this invention are as follows: Leveraging the decentralized and trustworthy distributed shared database attributes of blockchain, each microgrid distributed smart controller node can easily obtain various operational data shared by other microgrids within the group from the blockchain. Combined with the collected local microgrid operational data, and following the microgrid operational status intelligent perception rule base in the blockchain smart contract, the local microgrid operational status is intelligently perceived from the perspective of energy mutual assistance within the group. This achieves distributed intelligent perception of the microgrid group's operational status at each microgrid distributed smart controller node, as well as intelligent identification of the microgrid's operational status. This invention is beneficial for the coordinated operation of multi-point distributed microgrids with different construction times and electrical locations. Attached Figure Description

[0030] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0031] Figure 1 This is a system schematic diagram of the present invention;

[0032] Figure 2 A schematic diagram of the blockchain block generation process based on consensus and reward / punishment mechanisms.

[0033] Figure 3 Flowchart for generating distributed intelligent sensing and control strategies for microgrids based on blockchain smart contracts;

[0034] Figure 4 A schematic diagram of the microgrid cluster's operational state space partitioning;

[0035] Figure 5 A schematic diagram showing the fine spatial division of the operating states of microgrids operating in parallel under a group grid-connected state;

[0036] Figure 6A schematic diagram showing the fine spatial division of the operating states of microgrids operating in parallel under off-grid conditions;

[0037] Figure 7 A schematic diagram illustrating the fine division of the operating state space for microgrids operating in an islanded manner. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0040] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0041] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0042] like Figure 1 As shown, a specific embodiment of the present invention provides a blockchain-based microgrid distributed intelligent sensing and coordinated operation system, including a plurality of microgrid distributed monitoring units, a plurality of microgrid distributed intelligent controllers, and a blockchain; the plurality of microgrid distributed monitoring units are respectively connected to the plurality of microgrid distributed intelligent controllers; the plurality of microgrid distributed intelligent controllers are respectively connected to the blockchain; each microgrid is provided with a microgrid distributed monitoring unit and a microgrid distributed intelligent controller;

[0043] The microgrid distributed monitoring unit is used to monitor and collect the operating data of the renewable energy / energy storage unit / load unit of the microgrid on-site, and upload the collected operating data of the renewable energy / energy storage unit / load unit to the microgrid distributed intelligent controller of the corresponding microgrid.

[0044] The blockchain is used to store and share the current operating data, smart contracts, and control plans for each microgrid in the next period.

[0045] The microgrid distributed smart controller is used to download smart contracts stored in any block of the blockchain, as well as the operating data of other microgrids within the microgrid group required for microgrid group and microgrid status perception. Combined with the operating data monitored and collected by the microgrid distributed monitoring unit of this microgrid, and based on the microgrid operating status intelligent perception rule base in the smart contract, it performs local microgrid operating status intelligent perception from the perspective of energy mutual assistance within the microgrid group. Then, based on the perceived microgrid operating status and the control strategy knowledge base for each operating status in the smart contract, it completes the formulation of the control plan for the next period of this microgrid, and sends the control instructions to the corresponding microgrid distributed monitoring unit for execution.

[0046] Each microgrid has a pending data collection area, which is connected to the microgrid's distributed monitoring unit and distributed smart controller. This area stores the current-period operational data of the microgrid's renewable energy / energy storage units / load units, collected by the distributed monitoring unit. The distributed smart controller continuously packages the current-period operational data, smart contracts, and generated control plan data for the next period from the pending data collection area into blockchain blocks. Through a blockchain block-producing right competition mechanism based on consensus and rewards / penalties, the newly generated blocks are shared on the chain, allowing all microgrid distributed smart controllers to download the necessary data.

[0047] The basic building block of a blockchain—the block—is essentially a collection of data required for the intelligent sensing and coordinated operation of each microgrid. A block mainly consists of two parts: ① A block header, which links to previous blocks and provides integrity to the blockchain. The block header contains a version number, the hash value of the previous block header, the timestamp of the current block's generation, the Merkle root hash value, and a random number; ② The block body, which records the current operating data of the microgrid collected by smart contracts and distributed smart controller nodes, as well as the generated control plan data for the next operating period. Specifically, smart contracts include a rule base for intelligent sensing of the microgrid's operating status and a knowledge base for formulating control strategies for each operating state; the current operating data consists of the current operating data of the renewable energy / energy storage units / load units of the microgrid collected by the distributed smart controller; the control plan for the next operating period includes the intelligently sensed microgrid group status, the microgrid operating status, the next operating period PCC interactive power plan, the next operating period energy storage charging and discharging power plan, and the next operating period controllable load control plan.

[0048] The data recorded in the block body is hashed using a Merkle tree to generate a unique Merkle root hash, which is then recorded in the block header, ensuring the immutability of the data. Furthermore, the generated blocks are linked together in numerical order, forming a chain. If the value in any block is tampered with, the values ​​in all subsequent blocks will change accordingly. This mutual verification between blocks prevents information tampering and ensures the security of distributed data sharing within the blockchain. This is beneficial for the coordinated operation of multi-point distributed microgrids built at different times and located in different electrical locations.

[0049] like Figure 2 As shown, the specific method for competing for blockchain block production rights in this invention is as follows:

[0050] Each microgrid distributed smart controller node packages and generates new blocks according to the blockchain data structure, and competes for the right to produce blocks using the PoP (proof of PCC, PoP) consensus mechanism;

[0051] The microgrid distributed smart controller node that successfully obtains the right to produce a block will link the new block to the blockchain in sequence. Linking requires consensus approval from all microgrid distributed smart controller nodes. If approved, the new block is successfully produced and uploaded to the blockchain, and the node receives a reward to gain a competitive advantage in producing blocks in the next cycle. Otherwise, the new block is invalidated, and the node is penalized, reducing its probability of producing a block in the next cycle. The node that successfully produces a block exits the competition for this cycle. The blockchain adjusts the consensus difficulty coefficient to ensure that every microgrid distributed smart controller node can successfully produce and upload a block. Then, the remaining microgrid distributed smart controller nodes in the group compete again to produce and upload blocks according to the above process until all microgrid distributed smart controller nodes successfully upload their new blocks. This completes the sharing of microgrid group data information on the blockchain for this cycle.

[0052] The PoP consensus mechanism specifically combines the microgrid PCC interaction power and the energy storage state of charge (SOC) value, that is, each distributed smart controller node competes for the right to produce blocks through the following formula (1):

[0053]

[0054] In the formula: Hash(·) is the hash encryption algorithm; N is a random number; H is the other data in the block header besides N, including the version number, the hash value of the previous block header, the generation timestamp of the current block, and the Merkle root hash value; || represents the concatenation between data; Target represents the target difficulty threshold for hash encryption, the smaller the threshold, the harder it is to find a random value that meets the conditions; a and b are consensus difficulty adjustment coefficients, which are automatically adjusted by the blockchain according to the progress of the block production right competition; P PCCi PCC interactive power of microgrid i; SOC i This represents the energy storage state of charge of microgrid i.

[0055] A smart contract is essentially a protocol formulated by the distributed smart controller nodes of a microgrid. The protocol mainly consists of a smart sensing rule base for the microgrid's operating status and a knowledge base of control strategies for each state of the microgrid. Each distributed smart controller node takes various operating data from the microgrid cluster at the current time as input, and responds according to the smart sensing rule base for the microgrid's operating status in the blockchain smart contract. It senses and judges the operating status of the microgrid cluster and its own microgrid, and then, based on the sensed operating status, searches the knowledge base of control strategies for each state of the microgrid in the smart contract to formulate a control strategy for its own microgrid based on the collaborative operation of the cluster. A schematic diagram of the generation of distributed smart sensing and control strategies for a microgrid following the blockchain smart contract is shown below. Figure 3 As shown.

[0056] Leveraging the decentralized, trustworthy, distributed, and shared database attributes of blockchain, each microgrid distributed smart controller node can easily obtain various operational data shared by other microgrids within the group from the blockchain. Combined with the collected local microgrid operational data, and in accordance with the microgrid operational status intelligent perception rule base in the blockchain smart contract, the local microgrid operational status is intelligently perceived from the perspective of energy mutual assistance within the group. This enables distributed intelligent perception of the microgrid group's operational status at each microgrid distributed smart controller node, as well as intelligent identification of the operational status of the local microgrid.

[0057] The data required for microgrid distributed intelligent controllers to perform microgrid group and microgrid state perception includes the current time period for each microgrid PCC. i Switch status, group PCC0 switch status, power generation of each renewable energy source in each microgrid, state of charge (SOC) of each energy storage unit in each microgrid, and power consumption of each load unit in each microgrid.

[0058] There are two main operating modes for microgrid groups: group-connected and group-offset. Both group-connected and group-offset modes are further divided into two states: all microgrids are connected in parallel, and some microgrids are disconnected. Figure 4As shown. The microgrid distributed intelligent controller performs microgrid group state perception specifically based on the microgrid group PCC0 switch and the PCC of each microgrid. i The formula for determining and recognizing the open / closed state of a switch is as follows:

[0059]

[0060] In the formula: n is the number of microgrids contained in the microgrid group; PCC i PCC0 represents the PCC switching state of microgrid i; PCC0 represents the PCC switching state of the microgrid group, with 0 indicating off and 1 indicating on.

[0061] Microgrids joining a group can be categorized into two operating modes based on their PCC switching status: islanded operation (corresponding to PCC switching status being off) and parallel operation (corresponding to PCC switching status being on). Combining this with the aforementioned operational status classification of the microgrid group, the operational status space from the microgrid's perspective can be roughly divided into: parallel operation under group grid-connected conditions, parallel operation under group off-grid conditions, and islanded operation under microgrid disconnected conditions. The steps for the distributed intelligent controller of a microgrid to perceive the microgrid's operational status are as follows:

[0062] Step S1: Determine whether the microgrid group is in grid-connected or off-grid state, and further determine whether all microgrids within the microgrid group are in parallel or partially in parallel state. If the microgrid group is in grid-connected state and all microgrids are operating in parallel, proceed to step S2. If the microgrid group is in off-grid state and all microgrids are operating in parallel, proceed to step S3. If the microgrid group is in grid-connected state and some microgrids are operating in parallel, or if the microgrid group is in off-grid state and some microgrids are operating in parallel, proceed to step S4.

[0063] Step S2, the microgrid group is a fine division of the state space of all microgrids operating in parallel under grid-connected conditions, as shown in the example. Figure 5 As shown, the system sequentially determines whether the total power generation and consumption within the microgrid group are balanced, whether the total power generation and consumption within each microgrid are balanced, and the energy storage charge status of the microgrid, thereby further perceiving the specific status of all microgrids operating in parallel under the grid-connected state of the microgrid group.

[0064] The balance between total power generation and total power consumption within a microgrid cluster is primarily determined by comparing the total renewable energy power generation P within the microgrid cluster. DG Total power consumption P of the load OL The magnitude of the difference between P and P indicates whether the microgrid cluster is in a state of renewable energy surplus or renewable energy shortage. DG With P OL Calculated by the following formula:

[0065]

[0066] In the formula: b is the number of microgrids operating in parallel within the microgrid group, P DG P represents the total renewable energy generation capacity of the microgrid cluster. ZDGi The renewable energy generation capacity of microgrid i operating in parallel within the group is obtained by summing the generation capacities of each wind turbine and photovoltaic unit within the microgrid; P OL P represents the total power consumption of the microgrid group load; ZOLi The total load power of microgrid i operating in parallel within the group is obtained by summing the power of each rigid load, interruptible load, load that can be reduced, and load that can be shifted within the microgrid.

[0067] When P DG >P OL This indicates that the microgrid cluster as a whole is in a state of renewable energy surplus, when P DG >P OL This indicates that the microgrid cluster as a whole is in a state of insufficient renewable energy, when P DG =P OL This indicates that the microgrid cluster is in a state of balance between total power generation and total power consumption.

[0068] Whether the total power generation and total power consumption in each microgrid are balanced is mainly determined by the total renewable energy power generation P in a microgrid that is operating in parallel. ZDG With the power P of various types of loads ZOL The comparison between these two types of loads indicates which types of loads can absorb the renewable energy in the microgrid after prioritizing the power supply to each type of load. The power supply priority for each type of load, ranked from highest to lowest, is as follows: Rigid loads P... ZRDL , transferable load P ZSL It can reduce the load P ZIL and interruptible load P ZRL .

[0069] P, the layer of total power generation / consumption balance in a microgrid ZDG With P ZOL Calculated by the following formula:

[0070]

[0071] In the formula: P ZDG P represents the total renewable energy generation capacity within a microgrid operating in parallel; ZFPi P represents the power generation capacity of wind turbine unit i within the microgrid; ZPVi P represents the power generation of photovoltaic unit i within the microgrid; ZOL P represents the total power of all loads within the microgrid; ZRDLi P represents the power of the rigid load i within the microgrid; ZRLi P represents the power of interruptible load i within the microgrid; ZILiP represents the power that can be reduced from load i within this microgrid. ZSLi denoted as i, the power of the load that can be shifted within the microgrid; w, the number of wind turbine units within the microgrid; v, the number of photovoltaic units within the microgrid; k, the number of rigid loads within the microgrid; l, the number of loads that can be reduced within the microgrid; p, the number of loads that can be reduced within the microgrid; and q, the number of loads that can be shifted within the microgrid.

[0072] When P ZDG =P ZOL This characterizes the total power generation and total power consumption balance within a microgrid operating in parallel, when P ZDG >P ZOL or P ZDG <P ZOL This characterizes the imbalance between total power generation and total power consumption within a microgrid operating in parallel.

[0073] The state of charge (SOC) of energy storage in a microgrid is mainly determined by whether the current SOC of energy storage in a parallel-operating microgrid is higher than its SOC limit. The SOC classification formula is as follows:

[0074]

[0075] Where: SOC z The state of charge (SOC) of the energy storage in this microgrid represents the energy storage capacity. zx This represents the lower limit of the energy storage state of charge of the microgrid, which is usually set to 30%.

[0076] Step S3, the microgrid group is a finely divided state space of all microgrids operating in parallel under off-grid conditions, as shown in the example. Figure 6 As shown, the system sequentially determines whether the total power generation and total power consumption within the microgrid group are balanced, whether the total power generation and total power consumption within each microgrid are balanced, whether the microgrid energy storage is the group's main energy storage, and the energy storage charge status of the microgrid, thereby further perceiving the specific state of all microgrids operating in parallel under off-grid conditions.

[0077] The methods for determining whether the total power generation and consumption within a microgrid group are balanced, and whether the total power generation and consumption within each microgrid are balanced, are the same as those for determining whether the total power generation and consumption within a microgrid group are balanced when all microgrids are operating in parallel under grid-connected conditions, and will not be repeated here.

[0078] Determining whether a microgrid's energy storage is the primary energy storage unit is mainly achieved by comparing the remaining energy of the energy storage units of all microgrids operating in parallel under off-grid conditions, and selecting the energy storage unit with the largest remaining energy as the primary energy storage unit. Under off-grid conditions, a single energy storage unit with bidirectional power controllability and the largest remaining energy is required as the primary control unit, referred to as the primary energy storage unit, to provide system frequency and voltage support, balance power fluctuations within the system, and stabilize the off-grid operation of the microgrid group. By comparing the remaining energy of the energy storage units of all microgrids operating in parallel under off-grid conditions, the energy storage unit with the largest remaining energy is selected as the primary energy storage unit. Therefore, microgrids are divided into two states based on whether their energy storage units are selected as the primary energy storage unit. The formula for determining the primary energy storage unit is as follows:

[0079] Q s =Q m SOC m =max{Q1SOC z1 Q2SOC z2 ,…,Q i SOC zi ,…,Q d SOC zd};

[0080] In the formula: Q s Q represents the remaining energy of the main energy storage unit; m Indicates the main energy storage capacity; SOC m Indicates the state of charge (SOC) of the main energy storage unit. zi Q represents the state of charge of energy storage in a microgrid i (out of d) operating in parallel under off-grid conditions; i This represents the installed energy storage capacity of microgrid i.

[0081] The method for determining the state of charge of microgrid energy storage is as follows:

[0082] After determining whether a microgrid's energy storage is the main energy storage, the state of charge (SOC) of the energy storage is determined by comparing whether its SOC is higher than the specified lower limit. When the energy storage is not the main energy storage, the method for determining the SOC of the energy storage is the same as that for all microgrids operating in parallel with the microgrid group under grid-connected conditions. When the energy storage is the main energy storage, it is divided into two types based on whether the SOC of the main energy storage is greater than the specified upper limit of the SOC of the main energy storage, as shown in the following formula (7):

[0083]

[0084] Where: SOC m Indicates the state of charge (SOC) of the main energy storage unit. ms This indicates the upper limit of the main energy storage state of charge, which can be set according to the remaining energy of the main energy storage being able to ensure that the continuous power supply to rigid important loads within the group is not less than the planned duration of the group's off-grid operation.

[0085] Step S4: A microgrid group is either partially connected in parallel operation under grid-connected conditions or partially connected in parallel operation under off-grid conditions. The microgrids not connected in parallel are all islanded. Islanded microgrids refer to those microgrids that may exist in both grid-connected and off-grid conditions, where the corresponding PCC switch is in a split state. Their operating state space is finely divided as follows: Figure 7 As shown.

[0086] The system sequentially determines whether the total power generation and total power consumption in each microgrid are balanced, determines the energy storage charge status of the microgrid, and further perceives whether the microgrid group is partially operating in parallel under grid-connected conditions or partially operating in parallel under off-grid conditions.

[0087] The method for determining whether the total generation and total consumption within each microgrid are balanced is the same as the method described above, and will not be repeated here. Specifically, determining the state of charge (SOC) of the energy storage in a microgrid involves comparing the current SOC of the energy storage within the microgrid with the SOC of the energy storage in microgrids operating at 0, 1, or islanded operation. zj In comparison, the lower limit of the state of charge (SOC) for energy storage in islanded microgrids is required. zj The energy storage capacity is set based on the fact that the remaining energy can guarantee continuous power supply to rigid critical loads within the microgrid for a duration no less than the islanding plan duration, i.e.:

[0088]

[0089] Where: SOC zj This represents the lower limit of the state-of-charge requirement for energy storage in isolated microgrids; P ZRDL This represents the power of rigid, critical loads within the microgrid; T zj This indicates the planned duration of islanded operation of the microgrid. If the islanded operation is caused by an external fault, it is equal to the fault repair time. Q N This indicates the installed energy storage capacity of the microgrid.

[0090] The above-defined microgrid cluster and microgrid operation state space is the set of operation state perception rules in the microgrid operation state intelligent perception rule base in the blockchain smart contract. After perceiving and judging the operation state of the microgrid cluster and the microgrid itself based on the above rules, the control strategy of the microgrid under the identified state and control target can be automatically called through the control strategy knowledge base of the microgrid under each state in the blockchain smart contract, so as to complete the formulation of the microgrid control strategy based on the cluster collaborative operation position.

[0091] In a cluster-connected grid, the main grid provides system frequency and voltage support, maintaining system power balance. Therefore, each microgrid only needs to formulate a control strategy according to a preset cluster control objective. Under different cluster control objectives, the operating states of parallel microgrids in a cluster-connected grid have different control strategies. The cluster control objectives formulated in this invention mainly include three types: minimizing the interaction power of the cluster PCC0, maximizing peak shaving and valley filling, and maximizing energy storage lifetime. Of course, additional control objectives can be added according to actual operational needs, simply by enriching the control strategy knowledge base in the smart contract accordingly.

[0092] ① When the control objective is to minimize the interaction power between the group PCC0, the control principle is to maximize the local consumption of renewable energy through energy exchange between microgrids and reduce power interaction with the upper-level grid.

[0093] ② When the control objective is to maximize peak shaving and valley filling, the control period is divided into peak period, normal period and valley period. The control principle during the peak period is to meet the needs of the microgrid itself, that is, renewable energy should prioritize meeting the electricity demand of the microgrid load, and then feed the surplus renewable energy power outward. The control principle during the normal period is that the microgrid should flow naturally according to the balance of power generation and consumption within the grid. The control principle during the valley period is that the microgrid should prioritize drawing power from the upper-level grid.

[0094] ③ When the control objective is to "maximize the lifespan of energy storage", the control principle is to minimize the number of charging and discharging cycles of energy storage. Only when the state of charge of energy storage is lower than its lower limit should the energy storage be controlled to charge.

[0095] The following describes a microgrid operating in parallel under a group grid-connected state, in the "P" state. DG >P OL P ZDG ≥P ZOL SOC z <SOC zx Taking the state as an example, let's illustrate the control strategy of this microgrid under the above three control objectives:

[0096] ① When the control objective is to minimize the interaction power of the group PCC0, the surplus renewable energy generation power is fed back outwards, and the fed-out power is P. ZDG -P ZOL The feed-out power is preferentially transferred to other energy-deficient microgrids within the group to achieve energy mutual assistance; if all microgrids within the group have a surplus of renewable energy, the surplus power generation will be used to charge the energy storage of this microgrid.

[0097] ② When the control objective is to maximize peak shaving and valley filling, if the control period falls during peak hours, the surplus renewable energy generation power is fed back outwards, with the fed-back power being P. ZDG -P ZOLIf the regulation period is during normal times, the surplus power generation will be used to charge the energy storage of the microgrid first. When the energy storage is charged to the upper limit of the state of charge and there is still surplus power generation, it will be fed out. If the regulation period is during off-peak times, in addition to the surplus power generation charging the energy storage of the microgrid, power will also be drawn from the upper grid to charge the energy storage until it is fully charged.

[0098] ③ When the control objective is to "maximize the lifespan of energy storage", the surplus renewable energy generation power is preferentially fed out to other energy-deficient microgrids within the group. If there is still a surplus, the energy storage will be charged.

[0099] The control strategies for other operating states are similar to those in the example above, determined based on the aforementioned control principles, physical principles, and expert experience, and will not be elaborated further.

[0100] Because the voltage and frequency stability support of the main power grid is lost, the microgrids operating in parallel under off-grid conditions prioritize safe and stable operation and ensuring the longest possible power supply to critical loads within the group. The system provides voltage and frequency stability support through a selected primary energy storage unit. Therefore, when there is a surplus in renewable energy generation, the primary energy storage unit is prioritized for charging to maximize its remaining energy.

[0101] A microgrid operating in parallel under a group-off-grid state is in "P" DG >P OL P ZDG >P ZOL "Taking the operating state space as an example, this illustrates the control strategy of the microgrid under different states where energy storage is used as the primary energy storage:"

[0102] When the microgrid's primary energy storage is "SOC", m ≥SOC ms "Then the surplus renewable energy generation power of the microgrid is fed out, and the fed-out power is P." ZDG -P ZOL The feed-out power supplies other energy-deficient microgrids in the group to achieve energy mutual assistance. If there is a surplus, it supplies power to other microgrids whose energy storage is below the state of charge limit to charge them.

[0103] When the microgrid's primary energy storage is "SOC", m <SOC ms "Then the surplus renewable energy generation power of the microgrid will charge the energy storage of the microgrid until the upper limit of the state of charge is reached, and the charging power is P." ZDG -P ZOL If there is a surplus, it will be fed back to other energy-deficient microgrids within the group;

[0104] When the microgrid's energy storage is not the primary energy storage, if "SOC" z ≥SOC zx"Then the surplus renewable energy generation power of the microgrid is fed out, and the fed-out power is P." ZDG -P ZOL The feed-out power is prioritized to supply other energy-deficient microgrids within the group. If there is a surplus, it is supplied to the microgrid where the main energy storage is located to charge it to the upper limit.

[0105] When the microgrid's energy storage is not the primary energy storage, if "SOC" z <SOC zx If the surplus renewable energy generation power of the microgrid is used to charge the energy storage of the microgrid until the state of charge limit (30%), then any remaining surplus will be fed back to other energy-deficient microgrids in the group.

[0106] The control strategies for other operating states are similar to those in the example above, determined based on the aforementioned control principles, physical principles, and expert experience, and will not be elaborated further.

[0107] Microgrids operating in isolated mode lose the voltage and frequency stability support of the main power grid, and their control principle is to ensure safe and stable operation and guarantee the power supply to the important loads of the microgrid for the longest possible time.

[0108] A microgrid operating in an isolated state is in "P" ZRDL +P ZSL +P ZIL <P ZDG <P ZOL "Taking the operating state space as an example, the control strategy of this microgrid is explained:"

[0109] If "SOC" z ≥SOC zj "Then the renewable energy generation of this microgrid, in addition to meeting the rigid load P within the grid, will also meet the needs of the grid's rigid load P." ZRDL , transferable load P ZSL and load reduction P ZIL In addition, the interruptible load power P must also be satisfied. ZRL -(P ZOL -P ZDG In other words, the microgrid needs to disconnect P. ZOL -P ZDG interruptible load of varying size;

[0110] If "SOC" z <SOC zj "Then the renewable energy generation of this microgrid, in addition to meeting the needs of all rigid loads P within the grid, will also meet the needs of all rigid loads P within the grid." ZRDL , transferable load P ZSL and load reduction P ZIL In addition, the energy storage of this microgrid needs to be charged until the minimum state of charge (SOC) is reached. zj The charging power is P ZDG -(P ZRDL+P ZSL +P ZIL ).

[0111] The control strategies for other operating states are similar to those in the example above, determined based on the aforementioned control principles, physical principles, and expert experience, and will not be elaborated further.

[0112] Those skilled in the art will recognize that the units of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of the invention.

[0113] In the embodiments provided in this application, it should be understood that the division of units is only a logical functional division. In actual implementation, there may be other division methods, such as multiple units can be combined into one unit, one unit can be split into multiple units, or some features can be ignored.

[0114] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A blockchain-based microgrid distributed intelligent sensing and coordinated operation system, characterized in that, Includes several microgrid distributed monitoring units, several microgrid distributed smart controllers, and blockchain; The aforementioned microgrid distributed monitoring units are respectively connected to a number of microgrid distributed intelligent controllers; the number of microgrid distributed intelligent controllers are respectively connected to a blockchain; each microgrid is equipped with a microgrid distributed monitoring unit and a microgrid distributed intelligent controller; The microgrid distributed monitoring unit is used to monitor and collect the operating data of the renewable energy / energy storage unit / load unit of the microgrid on-site, and upload the collected operating data of the renewable energy / energy storage unit / load unit to the microgrid distributed intelligent controller of the corresponding microgrid. The blockchain is used to store and share the current operating data, smart contracts, and control plans for each microgrid in the next period. The microgrid distributed smart controller is used to download smart contracts stored in any block of the blockchain, as well as the operating data of other microgrids within the microgrid group required for microgrid group and microgrid status perception. Combined with the operating data monitored and collected by the microgrid distributed monitoring unit of this microgrid, and based on the microgrid operating status intelligent perception rule base in the smart contract, it performs local microgrid operating status intelligent perception from the perspective of energy mutual assistance within the microgrid group. Then, based on the perceived microgrid operating status and the control strategy knowledge base for each operating status in the smart contract, it completes the formulation of the control plan for the next period of this microgrid, and sends the control instructions to the corresponding microgrid distributed monitoring unit for execution. The data required by the microgrid distributed intelligent controller for microgrid group and microgrid status perception includes the current time period of each microgrid. Switch status, group Switch status, power generation of each renewable energy source in each microgrid, state of charge (SOC) of each energy storage unit in each microgrid, and power consumption of each load unit in each microgrid. The microgrid distributed intelligent controller performs microgrid group state perception specifically based on the microgrid group... Switches and microgrids The formula for determining and recognizing the open / closed state of a switch is as follows: ； In the formula: n This represents the number of microgrids contained in the microgrid group; microgrid i of Switch status; Indicates micro-network group Switch status: 0 indicates open, 1 indicates closed.

2. The blockchain-based microgrid distributed intelligent sensing and coordinated operation system according to claim 1, characterized in that, Each microgrid is equipped with a data collection area to be collected in blocks. The data collection area to be collected in blocks is connected to the microgrid distributed monitoring unit and the microgrid distributed intelligent controller of the microgrid, respectively, and is used to store the current time period operation data of the renewable energy / energy storage unit / load unit of the microgrid monitored and collected by the microgrid distributed monitoring unit.

3. The blockchain-based microgrid distributed intelligent sensing and coordinated operation system according to claim 2, characterized in that, The microgrid distributed smart controller continuously packages the current operating data of the microgrid, smart contracts, and the generated control plan data for the next period of the microgrid from the data collection area to be formed into a block of the blockchain. Through the blockchain block-producing right competition method based on consensus and reward and punishment mechanism, the generated new blocks are shared on the chain so that all microgrid distributed smart controllers can download the required data information.

4. The blockchain-based microgrid distributed intelligent sensing and coordinated operation system according to claim 1, characterized in that, The smart contract includes a rule base for intelligent sensing of the microgrid's operating status, and a knowledge base for formulating control strategies under various operating conditions. The current time period operation data refers to the current time period operation data of the renewable energy / energy storage units / load units of this microgrid collected by the microgrid distributed intelligent controller; the control plan for the next time period includes the intelligent sensing microgrid group status, microgrid operation status, PCC interactive power plan for the next time period of this microgrid, energy storage charging and discharging power plan for the next time period of this microgrid, and controllable load control plan for the next time period of this microgrid.

5. A blockchain-based microgrid distributed intelligent sensing and coordinated operation system according to claim 3, characterized in that, The specific method for competing for blockchain block production rights is as follows: Each microgrid distributed smart controller node packages and generates new blocks according to the blockchain data structure, and competes for the right to produce blocks using the PoP consensus mechanism. The microgrid distributed smart controller node that successfully obtains the right to produce a block will link the new block to the blockchain in sequence. Linking requires consensus approval from all microgrid distributed smart controller nodes. If approved, the new block is successfully produced and uploaded to the blockchain, and the node receives a reward to gain a competitive advantage in producing blocks in the next cycle. Otherwise, the new block is invalidated, and the node is penalized, reducing its probability of producing a block in the next cycle. The node that successfully produces a block exits the competition for this cycle. The blockchain adjusts the consensus difficulty coefficient to ensure that every microgrid distributed smart controller node can successfully produce and upload a block. Then, the remaining microgrid distributed smart controller nodes in the group compete again to produce and upload blocks according to the above process until all microgrid distributed smart controller nodes successfully upload their new blocks. This completes the sharing of microgrid group data information on the blockchain for this cycle.

6. A blockchain-based microgrid distributed intelligent sensing and coordinated operation system according to claim 5, characterized in that, The PoP consensus mechanism is specifically based on microgrids. PCC The interaction power and the energy storage state of charge (SOC) value are combined, that is, each distributed smart controller node competes for the block-producing right through the following formula (1): ； In the formula: It is a hash encryption algorithm; It is a random number; In the block header, except Other data besides the version number, the previous block header hash, the current block generation timestamp, and the Merkle root hash; Indicates the connection between data; This represents the target difficulty threshold for hash encryption; the smaller the threshold, the harder it is to find a random value that meets the criteria. a and b It is the consensus difficulty adjustment coefficient, which is automatically adjusted by the blockchain according to the progress of the block production right competition. For microgrids PCC interaction power; For microgrids The energy storage state of charge.

7. A blockchain-based microgrid distributed intelligent sensing and coordinated operation system according to claim 1, characterized in that, The steps for the microgrid distributed intelligent controller to perceive the microgrid's operating status are as follows: Step S1: Determine whether the microgrid group is in grid-connected or off-grid state, and further determine whether all microgrids within the microgrid group are in parallel or partially in parallel state; if the microgrid group is in grid-connected state and all microgrids are operating in parallel, proceed to step S2; if the microgrid group is in off-grid state and all microgrids are operating in parallel, proceed to step S3; if the microgrid group is in grid-connected state and some microgrids are operating in parallel, or if the microgrid group is in off-grid state and some microgrids are operating in parallel, proceed to step S4. Step S2: Sequentially determine whether the total power generation and total power consumption within the microgrid group are balanced, whether the total power generation and total power consumption within each microgrid are balanced, and the energy storage charge status of the microgrid is determined, so as to further perceive the specific status of all microgrids operating in parallel under the grid-connected state of the microgrid group; Step S3: Sequentially determine whether the total power generation and total power consumption within the microgrid group are balanced, whether the total power generation and total power consumption within each microgrid are balanced, whether the energy storage of the microgrid is the group master energy storage, and the energy storage charge status of the microgrid, so as to further perceive the specific status of all microgrids operating in parallel under the off-grid state of the microgrid group; Step S4: Sequentially determine whether the total power generation and total power consumption in each microgrid are balanced, determine the energy storage charge status of the microgrid, and further perceive the specific status of the microgrid group: whether the microgrids are partially operating in parallel under grid-connected conditions or partially operating in parallel under off-grid conditions.

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