An emergency control method and device for microgrids based on collaborative sharing of sudden power fluctuations.

Abstract

This invention discloses a microgrid emergency control method and device based on collaborative sharing of sudden power. It triggers event decisions by real-time monitoring of key switch states and immediately locks in the system state information before the event occurs. Based on the state information data, it calculates the total sudden power requiring emergency compensation. According to multiple dimensions such as the availability margin, response rate, and equipment status of each power source, it dynamically selects the optimal set of responding power sources. An adaptive dynamic response weight model is used to allocate the total sudden power according to the optimal proportion of each power source's technical performance. After safety verification, it generates feedforward control commands and rapidly issues them within milliseconds. This invention can control all distributed power sources within the microgrid that can participate in emergency regulation. It ensures that the highest-performing resource with the fastest response speed and largest regulation margin undertakes the main compensation task in emergencies, while also enabling other resources to cooperate according to their own capabilities to achieve emergency control of the microgrid.

Description

Technical Field

[0001] This invention belongs to the field of microgrid emergency control technology, and particularly relates to a microgrid emergency control method and device based on the collaborative sharing of sudden power. Background Technology

[0002] Microgrids, as a form of power system integrating diverse distributed energy sources, utilize power electronic inverters as interfaces to integrate renewable energy and energy storage systems. They have largely replaced synchronous generators with their inherent rotational inertia. This significant reduction in the system's equivalent rotational inertia directly weakens its inherent physical ability to resist frequency disturbances, making the limitations of existing hierarchical control strategies increasingly apparent.

[0003] Existing primary control, serving as the first line of defense, primarily relies on droop control and virtual synchronous machine technology. However, its implementation has inherent limitations in responding to sudden, large disturbances. The activation of this control level requires a precondition that the system frequency or voltage has already deviated. This passive response mode means it cannot proactively intervene in disturbances; by the initial stage of a disturbance, the most severe dynamic process of the system has already occurred. Because primary control is a decentralized, localized autonomous action, lacking a global coordination mechanism, it cannot optimize task allocation globally based on the technical characteristics of different power sources. This results in heterogeneous regulatory resources failing to form optimal synergy in emergencies, and overall response efficiency and capacity not being fully utilized. Secondary control, as a higher level, aims to eliminate the steady-state errors left by primary control and restore the system frequency to its rated value. Its entire closed-loop control process typically has a response cycle of tens of seconds. However, the process determining the transient stability of a microgrid is completed within hundreds of milliseconds. Therefore, the function of secondary control is limited to post-event steady-state recovery; its control role is practically absent during transient processes in emergency situations. In summary, existing microgrid control systems have revealed several shortcomings when dealing with clearly detectable, large-scale, sudden power imbalance events. There is an urgent need for an emergency control strategy that can quickly, collaboratively, and optimally schedule heterogeneous resources on a global scale. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes an emergency control method and device for microgrids based on collaborative sharing of sudden power fluctuations. The method and device control all distributed power sources within the microgrid that can participate in emergency regulation. When a large power imbalance event occurs in the microgrid due to a critical switch tripping, this method can proactively and collaboratively redistribute the sudden power fluctuations through feedforward control before traditional control strategies that rely on frequency deviation feedback can fully respond, thereby achieving transient stability control of the microgrid.

[0005] One of the objectives of this invention is achieved through the following technical solution: Firstly, this invention provides an emergency control method for microgrids based on the collaborative sharing of sudden power fluctuations, the method comprising the following steps:

[0006] Step 1: Event Triggering and State Locking: Real-time data acquisition of the operating status of key switches in the microgrid is performed using a preset sampling frequency; when a logic jump occurs in the closed state of any key switch, it is determined as a sudden event, and the system status information corresponding to the sampling point in the time window before the event occurs is immediately locked, including: active power transmission value, switch type, and operating status parameters of all online adjustable power sources in the microgrid;

[0007] Step 2: Imbalanced Power Quantification: Based on the system state information recorded in Step 1, calculate the total sudden power caused by the sudden event that requires emergency compensation from the system;

[0008] Step 3: Response resource assessment: Based on the operating status parameters of each adjustable power source in the status information and their preset intrinsic attributes, a multi-dimensional assessment model is used to select several response power sources that meet the emergency response conditions, forming a dynamic response power source set.

[0009] Step 4: Adaptive Share Allocation: Calculate the adaptive dynamic response weight of each power source in the response power source set using an allocation strategy based on available margin and performance coefficient, and determine the power compensation share that each response power source needs to bear accordingly.

[0010] Step 5: Command verification and distribution: After performing security verification and redistribution on the power compensation share obtained in Step 4, the command is distributed to the corresponding power source through the communication line.

[0011] Furthermore, in step 2, the total transient power is calculated based on the switch type and the active power transmission value.

[0012] Furthermore, the emergency response conditions for the multi-dimensional evaluation and screening logic in step 3 include:

[0013] Step 3.1: Operating Mode: The adjustable power supply is currently operating in a mode that allows the power to be scheduled in real time by an external controller;

[0014] Step 3.2: Adjustment margin: The available power adjustment margin of the adjustable power supply is greater than or equal to the preset lower limit;

[0015] Step 3.3: Response performance: The adjustable power supply promises a power ramp-up rate and communication latency that meet the requirement of being adjusted within the emergency response time threshold.

[0016] Furthermore, the available power adjustment margin in step 3.2 is the difference between the maximum allowable output power of the corresponding adjustable power supply and the output power recorded in the state information before the event occurred.

[0017] Furthermore, step 4 specifically includes the following process:

[0018] Step 4.1: Based on the available power adjustment margin of the power supply and the preset performance coefficient reflecting technical performance and response priority, calculate the adaptive dynamic response weight of each power supply in the response power supply set, i.e., the allocation ratio of the response power supply; the calculation formula is as follows:

[0019] Step 4.2: Determine the power compensation share that each response power source needs to bear based on the adaptive dynamic response weight and the total mutation power that requires emergency compensation from the system caused by the mutation event.

[0020] Furthermore, the adaptive dynamic response weight in step 4 is derived from the comprehensive weight of the power supply. It is determined that the overall weight of the power supply is calculated from the weighting factor of the performance factor, which includes at least: performance coefficient, available adjustment margin, adjustment cost, power ramp-up rate, or lifetime loss.

[0021] Furthermore, step 5 specifically includes the following process:

[0022] Step 5.1: Before issuing the instruction, pre-verify whether the safe operating limit of the corresponding response power supply is exceeded after the instruction is issued; if the limit is exceeded, reduce the compensation share of the power supply to the maximum allowable value within its safe limit, and then redistribute the resulting unallocated power deficit among the remaining qualified response power supplies in the set according to the adaptive dynamic response weight ratio described in Step 4.

[0023] Step 5.2: Within a preset emergency response time threshold after the occurrence of the mutation event, send the instruction to the corresponding response power source for execution via the communication link.

[0024] Secondly, the present invention also provides a microgrid emergency control device based on collaborative sharing of sudden power, including at least one processor and a memory communicatively connected to the processor. The memory stores computer program instructions that, when executed by the processor, implement the method. The device is logically divided into several functional modules, including: an event monitoring and locking module, an imbalance quantification module, a resource assessment module, a share allocation module, and an instruction generation module, for executing each step of the microgrid emergency control method based on collaborative sharing of sudden power, respectively.

[0025] Thirdly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the aforementioned microgrid emergency control method based on collaborative sharing of sudden power.

[0026] Fourthly, the present invention also provides a computer program product, including a computer program, which, when executed by a processor, implements the aforementioned microgrid emergency control method based on collaborative sharing of sudden power fluctuations.

[0027] The beneficial effects of this invention are:

[0028] (1) This invention abandons the passive mode of traditional control that relies on frequency deviation feedback, and realizes feedforward active control through event triggering and state information technology. The system can accurately quantify the power imbalance and immediately generate compensation commands at the millisecond instant when the disturbance occurs.

[0029] (2) This invention uses a multi-dimensional evaluation model and adaptive dynamic response weights to perform global optimization of heterogeneous adjustable resources across the entire network. This ensures that the high-quality resources with the fastest response speed and the largest adjustment margin can undertake the main compensation task in emergency situations, while also enabling other resources to cooperate based on their own capabilities. Attached Figure Description

[0030] Figure 1 This is a diagram illustrating the overall control method of a microgrid emergency control method based on the collaborative sharing of sudden power in Embodiment 1.

[0031] Figure 2 This is a test topology diagram of an off-grid microgrid in Example 2.

[0032] Figure 3 The key switch action in Example 2 is the frequency change of the system under traditional hierarchical control.

[0033] Figure 4 The key switch action in Example 2 describes the change in output power of each adjustable power supply under traditional layered control.

[0034] Figure 5 This refers to the change in power regulation (power compensation share) of each adjustable power source under traditional hierarchical control after the key switching action in Embodiment 2.

[0035] Figure 6 The key switch action in Embodiment 2 is the change in system frequency controlled by the present invention.

[0036] Figure 7 The key switch action in Embodiment 2 is the change in the output power of each adjustable power supply under the control of this invention.

[0037] Figure 8This refers to the change in the power adjustment amount (power compensation share) of each adjustable power source under the control of the present invention after the key switching action in Embodiment 2.

[0038] Figure 9 This refers to the change in the system dynamic response weight in the second embodiment of the present invention.

[0039] Figure 10 This is a structural diagram of a microgrid emergency control device based on the collaborative sharing of sudden power according to the present invention. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of the present invention and not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present invention.

[0041] Example 1:

[0042] like Figure 1 As shown, this embodiment provides a microgrid emergency control method based on collaborative sharing of sudden power fluctuations, including the following steps:

[0043] Step 1: Event Triggering and State Locking: Real-time data acquisition of the operating status of key switches in the microgrid is performed using a preset sampling frequency. When a logical transition occurs in the closed state of any key switch, it is determined as a sudden event, and the system state information within a preset time window (time t-1) prior to the event is immediately locked. This information includes at least the active power transmission value of the switch that experienced the logical transition at time t-1. And the operating status parameters of all online adjustable power sources in the microgrid;

[0044] Step 2: Imbalanced Power Quantization: Based on the system state information recorded in Step 1, calculate the total sudden power caused by the sudden event that requires emergency compensation from the system. .

[0045] Total mutation power The calculation formula is:

[0046]

[0047] Step 3: Response resource assessment: Based on the operating status parameters of each adjustable power source in the status information and their preset intrinsic attributes, one or more response power sources that meet the emergency response conditions are selected through multi-dimensional evaluation and screening logic to form a dynamic response power source set.

[0048] Step 3.1: Operating Mode: The adjustable power supply is currently operating in a mode that allows the power to be scheduled in real time by an external controller;

[0049] Step 3.2: Adjustment margin: The available power adjustment margin of the adjustable power supply. Greater than or equal to the preset lower limit Available power adjustment margin The calculation formula is:

[0050]

[0051] in, Let i be the maximum allowable output power of the i-th adjustable power supply. Let be the output power of the i-th adjustable power supply recorded in the state information at time t-1.

[0052] Step 3.3: Response Performance: The adjustable power supply promises a power ramp-up rate and communication latency that meet the requirement of being adjusted within the emergency response time threshold.

[0053] Step 4: Adaptive Share Allocation: Using a preset allocation model based on availability margin and performance coefficients, calculate the adaptive dynamic response weight of each power source in the response power source set. Based on this, the power compensation share that each response power source needs to bear is determined. .

[0054] Step 4.1: Calculate the adaptive dynamic response weight of each power source in the response power source set using an allocation strategy based on available margin and performance coefficient. The calculation formula is as follows:

[0055]

[0056] in: is the allocation ratio of the i-th response power source; n is the total number of power sources in the response power source set; , These are the preset performance coefficients for the i-th and j-th power supplies, respectively, reflecting their technical performance and response priority; These are the available power regulation margins for the i-th and j-th power supplies, respectively.

[0057] Furthermore, this allocation strategy can be extended to a multi-factor weighted strategy, with dynamic response weights. Through comprehensive weighting Sure:

[0058]

[0059]

[0060] in, Let be the overall weight of the i-th power source; This is the weighting factor for the k-th performance factor; This is the normalized value of the k-th performance factor of the i-th power source; This is the processing function for the k-th performance factor; the performance factor may include: performance coefficient, available adjustment margin, adjustment cost, power ramp-up rate, or lifetime loss.

[0061] Furthermore, the calculation formula described in step 4.1 is the basic formula, which has less computational load and faster response speed, and is suitable for scenarios with extremely high real-time requirements; the multi-factor weighting strategy is an advanced formula, which considers more conditions than the basic formula, such as cost and lifetime, and is suitable for scenarios with abundant computing resources and complex computing scenarios.

[0062] Step 4.2: Determine the power compensation share that each response power source needs to bear. The calculation formula is as follows:

[0063]

[0064] Step 5: Command verification and distribution: After performing security verification and redistribution on the power compensation share obtained in Step 4, the command is distributed to the corresponding power source through the communication line.

[0065] Step 5.1: Before issuing the instruction, pre-verify whether the safe operating limit of the corresponding power supply is exceeded after the instruction is issued; if the limit is exceeded, adjust the compensation share of the power supply. Reduced to the maximum permissible value within its safety limits The resulting unallocated power deficit will then be redistributed among the remaining eligible response power sources within the set. The formula for calculating the unallocated power deficit is as follows:

[0066]

[0067] Step 5.2: Through a high-reliability communication link, within a preset emergency response time threshold after the occurrence of the mutation event, send the instruction to the corresponding response power source for execution.

[0068] Furthermore, this method is a feedforward emergency control method based on discrete event triggering, which is executed before or in parallel with the conventional frequency deviation-based droop control response, for anticipatory compensation for predictable power surges.

[0069] Example 2:

[0070] Example 2 is an experimental simulation performed according to the method described in Example 1.

[0071] In this embodiment, to fully demonstrate the practical effect of the microgrid emergency control method based on collaborative sharing of sudden power fluctuations, a system is built as follows: Figure 2 The MATLAB / Simulink simulation model shown consists of three droop-controlled grid-connected energy storage units, one PQ-controlled photovoltaic array, three AC loads, and line impedance, forming an off-grid microgrid. The line resistance is 0.3Ω, and the line inductance is 1.5mH. The initial outputs of energy storage units 1 / 2 / 3 are 140 kW / 280 kW / 140 kW, with maximum allowable outputs of 320 kW / 400 kW / 200 kW, respectively. The AC loads 1 / 2 / 3 are 120 kW / 90 kW / 200 kW, respectively. A comparison is made between traditional hierarchical control and the control method of this invention. The microgrid's rated voltage is 380V, and the rated frequency is 50Hz. The system is set to disconnect the 100kW photovoltaic device within the microgrid after 6 seconds. Figure 3 The figure shows the frequency change of the system under traditional hierarchical control after the critical switch is activated; as shown. Figure 4 The output power changes of each adjustable power supply under traditional hierarchical control after the key switch is activated; for example... Figure 5 The diagram shows the changes in power regulation (power compensation share) of each adjustable power supply under traditional hierarchical control after the key switch is activated. Figure 5 The curves for Energy Storage 1 and Energy Storage 3 completely overlap; it can be seen that after the equipment switches on and off, the traditional strategy can only increase the power regulation through the PI controller when the frequency drops to the threshold, and the power sharing ratio remains unchanged before and after the event, which may lead to over-discharge of the power supply. The system frequency drops to a minimum of 49.89Hz and then slowly recovers, unable to restore the frequency urgently within 500ms after the event. Figure 6 The figure shows the frequency change of the system under the control of this invention after the key switch is activated, as shown in the figure. Figure 7 The output power of each adjustable power supply changes under the control of this invention after the key switch is activated; for example... Figure 8 The change in power regulation (power compensation share) of each adjustable power supply under the control of this invention after the key switch is activated; as shown. Figure 9 The figure shows the change in the dynamic response weight of the system in this invention. It can be seen that after the equipment is switched on, the invention quickly detects that the photovoltaic equipment is disconnected from the grid and issues a power adjustment amount to the adjustable power source in the microgrid according to the dynamic power sharing coefficient. The frequency of the microgrid can be quickly restored to about 50Hz within 100ms after the event occurs, and stabilized to 49.98Hz within 500ms, realizing emergency control and frequency restoration of the adjustable power source dynamic sharing after the microgrid experiences a power surge.

[0072] Example 3

[0073] Corresponding to the aforementioned embodiment of a microgrid emergency control method based on collaborative sharing of sudden power, the present invention also provides an embodiment of a microgrid emergency control device based on collaborative sharing of sudden power.

[0074] See Figure 10 The present invention provides an emergency control device for microgrids based on collaborative sharing of sudden power, comprising a memory and one or more processors. The memory stores executable code, and when the processor executes the executable code, it is used to implement an emergency control method for microgrids based on collaborative sharing of sudden power in the above embodiment.

[0075] The embodiment of the microgrid emergency control device based on collaborative sharing of transient power provided by this invention can be applied to any device with data processing capabilities, such as a computer. The device embodiment can be implemented through software, hardware, or a combination of both. Taking software implementation as an example, as a logical device, it is formed by the processor of any data processing device loading the corresponding computer program instructions from non-volatile memory into memory for execution. From a hardware perspective, such as... Figure 10 The diagram shown is a hardware structure diagram of any data processing-capable device, including a microgrid emergency control device based on collaborative sharing of sudden power fluctuations provided by this invention. (Except for...) Figure 10 In addition to the processor, memory, network interface, and non-volatile memory shown, any data processing device in the embodiment may also include other hardware depending on the actual function of the data processing device, which will not be described in detail here.

[0076] The specific implementation process of the functions and roles of each unit in the above device can be found in the implementation process of the corresponding steps in the above method, and will not be repeated here.

[0077] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of the present invention according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0078] This invention also provides a computer-readable storage medium storing a program thereon, which, when executed by a processor, implements a microgrid emergency control method based on collaborative sharing of sudden power fluctuations as described in the above embodiments.

[0079] The computer-readable storage medium can be an internal storage unit of any data processing device described in any of the foregoing embodiments, such as a hard disk or memory. The computer-readable storage medium can also be an external storage device of any data processing device, such as a plug-in hard disk, smart media card (SMC), SD card, flash card, etc., equipped on the device. Furthermore, the computer-readable storage medium can include both internal storage units and external storage devices of any data processing device. The computer-readable storage medium is used to store the computer program and other programs and data required by the data processing device, and can also be used to temporarily store data that has been output or will be output.

[0080] The present invention also provides a computer program product, including a computer program, which, when executed by a processor, implements the aforementioned microgrid emergency control method based on collaborative sharing of sudden power.

[0081] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A microgrid emergency control method based on mutation power cooperation, characterized in that, The method includes the following steps: Step 1: Event Triggering and State Locking: Real-time data acquisition of the operating status of key switches in the microgrid is performed using a preset sampling frequency; when a logic jump occurs in the closed state of any key switch, it is determined as a sudden event, and the system status information corresponding to the sampling point in the time window before the event occurs is immediately locked, including: active power transmission value, switch type, and operating status parameters of all online adjustable power sources in the microgrid; Step 2: Imbalanced Power Quantification: Based on the system state information recorded in Step 1, calculate the total sudden power caused by the sudden event that requires emergency compensation from the system; Step 3: Response resource assessment: Based on the operating status parameters of each adjustable power source in the status information and their preset intrinsic attributes, a multi-dimensional assessment model is used to select several response power sources that meet the emergency response conditions, forming a dynamic response power source set. Step 4: Adaptive Share Allocation: Using an allocation strategy based on available margin and performance coefficients, the adaptive dynamic response weight of each power source in the response power source set is calculated, and the power compensation share to be borne by each response power source is determined accordingly. The specific process includes: Step 4.1: based on the available power adjustment margin of the power supply and the preset performance coefficient reflecting the technical performance and response priority, the adaptive dynamic response weight of each power supply in the response power supply set, i.e. the allocation proportion of the response power supply, is calculated; the adaptive dynamic response weight is calculated by the comprehensive weight of the power supply It is determined that the comprehensive weight of the power supply is calculated by a weight factor of a performance factor, the performance factor at least including: a performance coefficient, an available adjustment margin, an adjustment cost, a power climbing rate or a life consumption; Step 4.2: Determine the power compensation share that each response power source needs to bear based on the adaptive dynamic response weight and the total sudden power caused by the sudden event that requires emergency compensation by the system; Step 5: Command Verification and Issuance: After performing security verification and redistribution on the power compensation share obtained in Step 4, the command is issued to the corresponding power source via the communication line; the specific process includes: Step 5.1: Before issuing the instruction, pre-verify whether the safe operating limit of the corresponding response power supply is exceeded after the instruction is issued; if the limit is exceeded, reduce the compensation share of the power supply to the maximum allowable value within its safe limit, and then redistribute the resulting unallocated power deficit among the remaining qualified response power supplies in the set according to the adaptive dynamic response weight ratio described in Step 4. Step 5.2: Within a preset emergency response time threshold after the occurrence of the mutation event, send the instruction to the corresponding response power source for execution via the communication link.

2. The microgrid emergency control method based on collaborative sharing of sudden power fluctuations according to claim 1, characterized in that, In step 2, the total transient power is calculated based on the switch type and the active power transmission value.

3. The microgrid emergency control method based on collaborative sharing of sudden power fluctuations according to claim 1, characterized in that, The multi-dimensional evaluation and screening logic in step 3 includes the following emergency response conditions: Step 3.1: Operating Mode: The adjustable power supply is currently operating in a mode that allows the power to be scheduled in real time by an external controller; Step 3.2: Adjustment margin: The available power adjustment margin of the adjustable power supply is greater than or equal to the preset lower limit; Step 3.3: Response performance: The adjustable power supply promises a power ramp-up rate and communication latency that meet the requirement of being adjusted within the emergency response time threshold.

4. The microgrid emergency control method based on collaborative sharing of sudden power fluctuations according to claim 3, characterized in that, The available power adjustment margin in step 3.2 is the difference between the maximum allowable output power of the corresponding adjustable power supply and the output power recorded in the state information before the event occurred.

5. A microgrid emergency control device based on collaborative sharing of sudden power fluctuations, characterized in that, The device includes at least one processor and a memory communicatively connected to the processor. The memory stores computer program instructions that, when executed by the processor, implement the method as described in any one of claims 1 to 4. The device is logically divided into several functional modules, including: an event monitoring and locking module, an imbalance quantification module, a resource assessment module, a share allocation module, and an instruction generation module, for executing the respective steps of the microgrid emergency control method based on sudden power sharing.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the microgrid emergency control method based on the collaborative sharing of sudden power as described in any one of claims 1 to 4.

7. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements a microgrid emergency control method based on the collaborative sharing of sudden power as described in any one of claims 1-4.

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