A power distribution network voltage management device

Abstract

The application relates to the technical field of voltage management, in particular to a power distribution network voltage management device, which comprises a data acquisition module, a data calculation module, an abnormality judgment module and a negative feedback module. The application significantly improves the voltage stability and power supply reliability of the power distribution network by monitoring and analyzing the key parameters of the power system in real time. The automatic abnormality judgment and load adjustment mechanism of the device not only reduces human intervention and operation errors, but also effectively prevents the risk of voltage collapse and power supply interruption by quickly responding to voltage deviation and stability problems. In addition, the closed-loop control strategy enables the system to dynamically adjust the load change rate threshold according to real-time feedback, enhancing the adaptive ability of the system and ensuring the stability of the voltage under various loads and operating conditions. In the long term, this intelligent voltage management helps to reduce power loss and prolong the service life of power equipment.

Description

Technical Field

[0001] This invention relates to the field of voltage regulation technology, and in particular to a voltage regulation device for power distribution networks. Background Technology

[0002] The demand for efficient, stable, and intelligent management in modern power systems is growing. With economic development and accelerated industrialization, power system loads are becoming increasingly complex and unpredictable. Furthermore, the integration of new loads such as distributed energy resources and electric vehicle charging stations presents distribution networks with even more severe voltage stability challenges. In addition, competition in the electricity market and users' increasing demands for power quality have driven the research and application of distribution network voltage management technologies. Distribution network voltage management devices, through real-time monitoring and automatic adjustment, can quickly respond to voltage deviations and load changes in the power grid, maintain voltage stability, improve power supply reliability, and ensure the safe, economical, and efficient operation of the power system.

[0003] Patent document CN106786657A discloses a comprehensive power quality management device for power distribution networks. The device includes a main circuit and a control circuit. The main circuit includes a transformer TR, a filter assembly LC, a filter reactor La, a first three-level inverter CON1, and a second three-level inverter CON2. The primary winding of the transformer TR is connected in series between the power supply U1 and the load FZ1. The first three-level inverter CON1 is connected in series to the power grid after passing through the filter assembly LC and the secondary winding of the transformer TR. The second three-level inverter CON2 is connected in parallel to the load FZ1 after passing through the filter reactor La. The control signal input terminals of the first three-level inverter CON1 and the second three-level inverter CON2 are electrically connected to the control signal output terminal of the control circuit, respectively. This device only collects voltage and current information between the primary side of the transformer and the load, which may not be able to comprehensively monitor the state of the power grid, including three-phase imbalance and harmonic content. Furthermore, the lack of real-time data collection from the load side may result in an inaccurate assessment of the impact of load changes on the power grid. Summary of the Invention

[0004] Therefore, the present invention provides a distribution network voltage management device to overcome the problem of poor voltage management effect caused by inaccurate analysis of power grid status information due to single data collection in the prior art.

[0005] To achieve the above objectives, the present invention provides a power distribution network voltage management device, comprising:

[0006] The data acquisition module is used to collect real-time voltage, real-time current, real-time active power, and node voltage recovery time at each node of the distribution network.

[0007] The data calculation module is connected to the data acquisition module and is used to calculate voltage deviation, voltage stability index and load current change rate based on real-time voltage, real-time current, real-time active power, rated voltage and preset time increment.

[0008] An anomaly determination module, connected to the data calculation module, is used to determine the type of anomaly based on the voltage deviation, the voltage stability index, the load current change rate, a preset voltage deviation threshold, a preset voltage stability index threshold, and a preset standard current load change rate threshold. When an anomaly is determined to occur, the anomaly determination module determines the degree of load anomaly based on the load current change rate, a first current load change rate threshold, and a second current load change rate threshold, and makes corresponding adjustments based on the degree of load anomaly.

[0009] The negative feedback module is connected to both the data acquisition module and the anomaly determination module. It is used to determine the need to adjust the first current load change rate threshold based on the node voltage recovery time, the preset target node voltage recovery time, and the preset time increment. When the negative feedback module determines that the first current load change rate threshold needs to be adjusted, it adjusts the first current load change rate threshold based on the node voltage recovery time, the target node voltage recovery time, and the preset load change rate safety range. When the negative feedback module determines that the second current load change rate threshold needs to be adjusted, it adjusts the second current load change rate threshold based on the node voltage recovery time, the target node voltage recovery time, the preset time increment, and the preset load change rate safety range.

[0010] Furthermore, when the anomaly detection module determines that a load anomaly has occurred, it compares the load current change rate with a first current load change rate threshold and a second current load change rate threshold, respectively.

[0011] If the load current change rate is less than the first current load change rate threshold, the anomaly detection module determines it as a slight change anomaly and reduces the load on non-critical parts.

[0012] If the load current change rate is greater than or equal to the first current load change rate threshold and less than the second current load change rate threshold, the anomaly detection module determines it as a moderate change anomaly and issues a demand response signal.

[0013] If the rate of change of the load current exceeds the second current load change rate threshold, the anomaly detection module determines it to be a drastic change anomaly, disconnects the power supply, and issues an alarm.

[0014] Furthermore, the negative feedback module makes a determination based on the node voltage recovery time, recovery time threshold, and preset time increment acquired by the data acquisition module.

[0015] If the node voltage recovery time is greater than or equal to the recovery time threshold, and less than the sum of the recovery time threshold and the preset time increment, the negative feedback module determines that the first current load change rate threshold needs to be adjusted.

[0016] If the node voltage recovery time is greater than or equal to the sum of the recovery time threshold and the preset time increment, the negative feedback module determines that the second current load change rate threshold needs to be adjusted.

[0017] Furthermore, when the negative feedback module determines that the first current load change rate threshold needs to be adjusted, it calculates the adjusted first current load change rate threshold based on the node voltage recovery time and a preset safe range for the load change rate.

[0018] Q1'=Q1×(1+k×(T-T') / T'), Q1”=max(min(Q1’,Qmax),Qmin),

[0019] Where Q1' is the first current load change rate threshold after one calculation, Q1 is the first current load change rate threshold before adjustment, k is the conversion coefficient, T' is the recovery time threshold, T is the node voltage recovery time, Q1” is the first current load change rate threshold after adjustment, Qmax is the maximum value of the safe range of load change rate, and Qmin is the minimum value of the safe range of load change rate.

[0020] Furthermore, when the negative feedback module determines that the second current load change rate threshold needs to be adjusted, it calculates the adjusted second current load change rate threshold based on the node voltage recovery time, the preset load change rate safety range, and the preset time increment.

[0021] Q2'=Q2×(1+k×(T-(T'+ΔT)) / T'), Q2”=max(min(Q2’,Qmax),Qmin),

[0022] Where Q2' is the second current load change rate threshold after one calculation, Q2 is the second current load change rate threshold before adjustment, k is the conversion coefficient, ΔT is the preset time increment, Q2” is the second current load change rate threshold after adjustment, Qmax is the maximum value of the safe range of load change rate, and Qmin is the minimum value of the safe range of load change rate.

[0023] Furthermore, the data calculation module calculates the voltage deviation based on the real-time voltage and the rated voltage.

[0024] v = (V - V0) / V0,

[0025] Where v is the voltage deviation, V is the real-time voltage, and V0 is the rated voltage.

[0026] Furthermore, the data calculation module calculates voltage stability indicators based on real-time voltage and real-time active power.

[0027] ,

[0028] Where s is the voltage stability index and P is the real-time active power. It is a partial derivative.

[0029] Furthermore, the data calculation module calculates the load current change rate based on a preset time increment and the change in real-time current within the time increment.

[0030] C = ΔI / ΔT,

[0031] Where C is the load current change rate, ΔI is the change in real-time current over time increment, and ΔT is the preset time increment.

[0032] Furthermore, the anomaly detection module compares the voltage deviation with a preset voltage deviation threshold.

[0033] If the voltage deviation is greater than or equal to the voltage deviation threshold, the anomaly detection module determines that a voltage deviation anomaly has occurred and compares the voltage stability index with the voltage stability index threshold.

[0034] If the voltage stability index is greater than or equal to the voltage stability index threshold, the anomaly detection module determines that a voltage stability anomaly has occurred.

[0035] Furthermore, when the anomaly detection module determines that a voltage stability anomaly has occurred, it compares the load current change rate with a standard current load change rate threshold.

[0036] If the rate of change of load current is greater than the standard current load change rate threshold, the anomaly detection module determines that a load anomaly has occurred.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] By monitoring and analyzing key parameters of the power system in real time, the voltage stability and power supply reliability of the distribution network are significantly improved. The device's automated anomaly detection and load adjustment mechanisms not only reduce human intervention and operational errors, but also effectively prevent the risks of voltage collapse and power supply interruption by quickly responding to voltage deviations and stability issues. In addition, the closed-loop control strategy enables the system to dynamically adjust the load change rate threshold based on real-time feedback, enhancing the system's adaptability and ensuring voltage stability under various load and operating conditions. In the long term, this intelligent voltage management not only helps reduce power loss, avoid equipment overload, and extend the service life of power equipment, but also reduces maintenance costs and improves the economic efficiency of the power system. At the same time, by ensuring the continuity and stability of power supply, it enhances the user's electricity experience. Furthermore, the device can also improve production efficiency by reducing power outages.

[0039] Furthermore, by responding to different load changes in a tiered manner, more refined and effective voltage management can be provided. Reducing non-critical loads during minor anomalies can maintain grid stability without affecting critical services. Demand response signals issued during moderate anomalies can incentivize users to reduce electricity consumption or increase generation, helping to avoid more serious grid problems. Emergency measures during drastic anomalies, such as power disconnection and alarms, can prevent grid overload and potential equipment damage, ensuring the long-term reliability of the grid and the safety of users' electricity consumption. Through this multi-layered protection and response strategy, distribution network voltage management devices can improve the resilience and adaptability of the entire power system.

[0040] Furthermore, the dynamic adjustment mechanism of the negative feedback module offers significant benefits for distribution network voltage management. Firstly, it allows the device to automatically adjust the load change rate threshold based on real-time voltage recovery, resulting in more precise and efficient voltage management. Secondly, by adjusting the threshold in a timely manner, unnecessary over- and under-adjustments can be avoided, reducing the impact on user electricity consumption and improving grid stability. In addition, this adaptive adjustment helps prevent voltage collapse, enhances the grid's ability to respond to emergencies, and ensures the continuity and reliability of power supply. Ultimately, the intelligent adjustment of the negative feedback module can improve the overall operating efficiency of the power system and the user's electricity experience.

[0041] Furthermore, by dynamically adjusting the first current load change rate threshold, the system can respond precisely to the real-time operating conditions of the power grid, improving the flexibility and adaptability of voltage management. This method ensures that even when the voltage recovery time exceeds expectations, the system can maintain voltage stability by adjusting the load change rate threshold, avoiding voltage collapse and enhancing the robustness of the power grid. Simultaneously, by limiting the threshold within a safe range, it ensures that power grid equipment is not damaged by excessively rapid load changes, thereby extending equipment life and reducing maintenance costs.

[0042] Furthermore, the adjustment strategy of the negative feedback module provides an adaptive load management mechanism for the distribution network, which can dynamically adjust the load change rate threshold according to the actual voltage recovery situation. This dynamic adjustment helps optimize the grid's response speed, enabling it to more effectively address the problem of voltage recovery delay. By keeping the threshold within a safe range, this mechanism not only ensures the stability of the grid but also avoids equipment damage or power outages caused by excessively rapid load changes.

[0043] Furthermore, calculating voltage deviation can provide the deviation between real-time voltage and rated voltage, helping to detect voltage anomalies in a timely manner. Quantifying voltage deviation facilitates comparison and analysis, providing a numerical basis for voltage stability analysis, and providing accurate voltage deviation data for the anomaly detection module to help it make accurate anomaly type judgments. Through the calculation of voltage deviation, preventive measures can be taken in advance to avoid power instability or equipment damage caused by voltage problems.

[0044] Furthermore, voltage stability indices are obtained by calculating the partial derivative of real-time voltage with respect to real-time active power. This process involves a quantitative analysis of the relationship between voltage changes and active power changes, thereby assessing voltage stability under active power variations. The advantage of this method is its ability to accurately capture the voltage response characteristics to load changes, providing crucial information for distribution network voltage management devices. This enables the system to monitor and predict voltage stability in real time, take timely adjustment measures, and effectively prevent voltage collapse.

[0045] Furthermore, accurate calculation of the load current change rate is crucial for timely detection and response to load fluctuations in the power grid. It can help the system prevent voltage instability and power outages, thereby improving the stability of the power grid and the reliability of power supply.

[0046] Furthermore, through continuous monitoring and assessment, distribution network voltage management devices can quickly respond to voltage anomalies, prevent voltage collapse, and ensure grid stability and power supply continuity. In addition, accurately identifying the type of anomaly helps implement more precise adjustment strategies, improves voltage management efficiency, and enhances the reliability of the entire power system and the user's electricity experience.

[0047] Furthermore, the load anomaly detection mechanism allows the system to further confirm whether there are load problems after detecting voltage stability anomalies, thereby enabling a more comprehensive assessment of the grid's health. Once a load anomaly is identified, the system can take corresponding measures, such as adjusting power generation, reallocating loads, or implementing demand-side management strategies, to alleviate grid pressure, prevent voltage collapse, and ensure the stability and reliability of power supply. Attached Figure Description

[0048] Figure 1The diagram shown is a structural schematic of the power distribution network voltage management device in this embodiment.

[0049] Figure 2 This is the logic diagram for determining the degree of abnormality in current load in this embodiment;

[0050] Figure 3 This is the logic diagram for determining the current load threshold adjustment in this embodiment;

[0051] Figure 4 This is the logic diagram for determining voltage deviation anomalies in this embodiment. Detailed Implementation

[0052] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0053] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0054] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0055] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0056] Please see Figure 1 As shown, it is a structural schematic diagram of the power distribution network voltage management device in this embodiment;

[0057] This embodiment provides a power distribution network voltage management device, including:

[0058] The data acquisition module is used to collect real-time voltage, real-time current, real-time active power, and node voltage recovery time at each node of the distribution network.

[0059] The data calculation module is connected to the data acquisition module and is used to calculate voltage deviation, voltage stability index and load current change rate based on real-time voltage, real-time current and real-time active power.

[0060] An anomaly determination module, connected to the data calculation module, is used to determine the type of anomaly based on voltage deviation, voltage stability index, load current change rate, preset voltage deviation threshold, preset voltage stability index threshold, and preset standard current load change rate threshold. When an anomaly is determined to occur, the anomaly determination module determines the degree of load anomaly based on the load current change rate, the first current load change rate threshold, and the second current load change rate threshold, and makes corresponding adjustments based on the degree of load anomaly.

[0061] The negative feedback module is connected to both the data acquisition module and the anomaly determination module. It is used to determine the need to adjust the first current load change rate threshold based on the node voltage recovery time, the preset target node voltage recovery time, and the preset time increment. When the negative feedback module determines that the first current load change rate threshold needs to be adjusted, it adjusts the first current load change rate threshold based on the node voltage recovery time, the target node voltage recovery time, and the preset load change rate safety range. When the negative feedback module determines that the second current load change rate threshold needs to be adjusted, it adjusts the second current load change rate threshold based on the node voltage recovery time, the target node voltage recovery time, the preset time increment, and the preset load change rate safety range.

[0062] First, the data acquisition module collects real-time voltage, current, and power data from each node of the distribution network. Then, the data calculation module calculates voltage deviation, voltage stability indicators, and load current change rate based on this data. The anomaly detection module compares these calculation results with preset thresholds to identify and determine the type and severity of voltage anomalies, and adjusts the load as necessary. Finally, the negative feedback module automatically adjusts the load change rate threshold based on the comparison between the voltage recovery time and the target time to optimize the voltage management effect.

[0063] By monitoring and analyzing key parameters of the power system in real time, the voltage stability and power supply reliability of the distribution network are significantly improved. The device's automated anomaly detection and load adjustment mechanisms not only reduce human intervention and operational errors, but also effectively prevent the risks of voltage collapse and power supply interruption by quickly responding to voltage deviations and stability issues. In addition, the closed-loop control strategy enables the system to dynamically adjust the load change rate threshold based on real-time feedback, enhancing the system's adaptability and ensuring voltage stability under various load and operating conditions. In the long term, this intelligent voltage management not only helps reduce power loss, avoid equipment overload, and extend the service life of power equipment, but also reduces maintenance costs and improves the economic efficiency of the power system. At the same time, by ensuring the continuity and stability of power supply, it enhances the user's electricity experience. Furthermore, the device can also improve production efficiency by reducing power outages.

[0064] The voltage deviation threshold refers to the difference between the actual voltage and the rated voltage. The voltage deviation threshold is a standard for judging whether the voltage is within an acceptable range. It depends on the power system standards, the equipment's sensitivity to voltage fluctuations, and historical data, etc. It is usually within the range of ±5% to ±10% of the rated voltage. In this embodiment, it is set to ±5V. A stricter threshold helps to maintain voltage stability and reduce the impact of voltage anomalies on the equipment.

[0065] The voltage stability index threshold is calculated based on real-time voltage and active power and is used to evaluate voltage stability. It depends on the system's design standards, historical stability data, and load characteristics, and is generally set between 1.0 and 1.5. This threshold is suitable for applications with high voltage stability requirements. In this embodiment, the voltage stability index threshold is set to 1.2 to balance system stability and tolerance to voltage fluctuations. This threshold is neither too strict, avoiding frequent adjustments due to small fluctuations, nor too lenient, ensuring timely action when voltage stability shows a significant decline.

[0066] The standard current load change rate threshold is the rate at which the current load changes within a specific time period. It depends on the system's load characteristics, historical load change data, user needs, etc. It is generally set between 0.01 and 0.05 and is suitable for systems that are sensitive to load changes or require fine control. In this embodiment, it is set to 0.03, which allows for fine-tuning of slight load changes without affecting the user's normal power consumption.

[0067] The first current load change rate threshold is the criterion for judging slight abnormal changes. It depends on the system's tolerance to slight load changes and is generally set between 0.05 and 0.15. It is suitable for general load changes and can balance the system's stability and response speed. In this embodiment, it is set to 0.06, which allows the device to react to small load changes without being too sensitive.

[0068] The second current load change rate threshold is the criterion for judging moderate to drastic abnormal changes. It depends on the system's response strategy to large load changes. It is generally set to a value above 0.15. In this embodiment, it is set to 0.15, which provides a boundary for moderate to large load changes. When the load change exceeds the first threshold but does not reach the second threshold, the system will issue a demand response signal. This usually means that more proactive measures are needed to deal with the load change, such as adjusting the power generation plan or increasing the reserve capacity.

[0069] The target node voltage recovery time is the time it takes for the system to restore the voltage to normal. It depends on the system's recovery capability and the equipment's tolerance to voltage interruption. Generally, the shorter the setting, the better. However, it is necessary to balance system capability and cost. In this embodiment, it is set to 0.3 seconds, which can quickly restore the voltage and reduce the impact of voltage interruption on users.

[0070] The safe range of load change rate is the maximum and minimum acceptable value of the load change rate without affecting system stability. It depends on the stability of the system and the safe operating range of the equipment. Generally, it is set according to the system design and historical operating data. In this embodiment, the minimum value is set to 0.01 and the maximum value is set to 0.2, which can ensure that the load change does not exceed the limit of the system's safe operation and avoid equipment damage or system instability.

[0071] The time increment is a parameter used in distribution network voltage management devices to assess and adjust the load change rate threshold. It represents the additional time the system waits to observe the voltage recovery after the voltage recovery time exceeds a preset threshold before adjusting the threshold. It is typically set between a few seconds and tens of seconds, suitable for systems with rapid response. In this embodiment, it is set to 0.2 seconds. Choosing an appropriate time increment provides a buffer period for the system, allowing for more accurate assessment of voltage recovery and more suitable adjustments to the load change rate threshold. Shorter time increments are suitable for applications requiring rapid response, while longer time increments are suitable for applications requiring more careful assessment of voltage recovery. By setting a reasonable time increment, the accuracy of voltage management can be improved, unnecessary adjustments reduced, and thus the overall operating efficiency and stability of the power grid improved.

[0072] Please continue reading. Figure 2 As shown, this is the logic diagram for determining the degree of abnormality in current load in this embodiment;

[0073] Specifically, when the anomaly detection module determines that a load anomaly has occurred, it compares the load current change rate with a first current load change rate threshold and a second current load change rate threshold, respectively.

[0074] If the load current change rate is less than the first current load change rate threshold, the anomaly detection module determines it as a slight change anomaly and reduces the load on non-critical parts.

[0075] If the load current change rate is greater than or equal to the first current load change rate threshold and less than the second current load change rate threshold, the anomaly detection module determines it as a moderate change anomaly and issues a demand response signal.

[0076] If the rate of change of the load current exceeds the second current load change rate threshold, the anomaly detection module determines it to be a drastic change anomaly, disconnects the power supply, and issues an alarm.

[0077] Different levels of load anomalies are identified by comparing the real-time monitored load current change rate with two preset current load change rate thresholds. If the load current change rate is below the first threshold, the module classifies the anomaly as a minor change and takes measures to reduce non-critical loads to balance the system. When the change rate exceeds the first threshold but is below the second threshold, it is determined to be a moderate anomaly, at which point the module will issue a demand response signal to incentivize load-side management or adjust generator output. If the change rate exceeds the second threshold, it is considered a severe anomaly, and the module will take more drastic measures, including disconnecting the power supply and triggering an alarm, to protect the system from damage.

[0078] By responding to different load changes in a tiered manner, more refined and effective voltage management is provided. Reducing non-critical loads during minor anomalies can maintain grid stability without affecting critical services. Demand response signals issued during moderate anomalies can incentivize users to reduce electricity consumption or increase generation, helping to avoid more serious grid problems. Emergency measures during drastic anomalies, such as power outages and alarms, can prevent grid overload and potential equipment damage, ensuring the long-term reliability of the grid and the safety of users' electricity consumption. Through this multi-layered protection and response strategy, distribution network voltage management devices can improve the resilience and adaptability of the entire power system.

[0079] Please continue reading. Figure 3 As shown, it is the logic diagram for determining the adjustment of the current load threshold in this embodiment;

[0080] Specifically, the negative feedback module makes its determination based on the node voltage recovery time, recovery time threshold, and preset time increment collected by the data acquisition module.

[0081] If the node voltage recovery time is greater than or equal to the recovery time threshold, and less than the sum of the recovery time threshold and the preset time increment, the negative feedback module determines that the first current load change rate threshold needs to be adjusted.

[0082] If the node voltage recovery time is greater than or equal to the sum of the recovery time threshold and the preset time increment, the negative feedback module determines that the second current load change rate threshold needs to be adjusted.

[0083] The negative feedback module analyzes and judges the node voltage recovery time based on the data acquisition module, combined with a preset recovery time threshold and time increment. When the actual node voltage recovery time reaches or exceeds the preset recovery time threshold, but is lower than the sum of the threshold and the time increment, the negative feedback module determines that the first current load change rate threshold needs to be adjusted. If the recovery time exceeds this sum, it indicates that the voltage recovery is too slow, and the negative feedback module further determines that the second current load change rate threshold needs to be adjusted. Such adjustments are based on the actual voltage recovery situation to optimize the system's response and adaptability.

[0084] The dynamic adjustment mechanism of the negative feedback module offers significant benefits for voltage management in distribution networks. Firstly, it allows the device to automatically adjust the load change rate threshold based on real-time voltage recovery, resulting in more precise and efficient voltage management. Secondly, by adjusting the threshold in a timely manner, unnecessary over- and under-adjustments can be avoided, reducing the impact on user electricity consumption and improving grid stability. Furthermore, this adaptive adjustment helps prevent voltage collapse, enhances the grid's ability to respond to emergencies, and ensures the continuity and reliability of power supply. Ultimately, the intelligent adjustment of the negative feedback module can improve the overall operating efficiency of the power system and the user's electricity experience.

[0085] Specifically, when the negative feedback module determines that the first current load change rate threshold needs to be adjusted, it calculates the adjusted first current load change rate threshold based on the node voltage recovery time and the preset load change rate safety range.

[0086] Q1'=Q1×(1+k×(T-T') / T'), Q1”=max(min(Q1, Qmax),Qmin),

[0087] Where Q1' is the first current load change rate threshold after one calculation, Q1 is the first current load change rate threshold before adjustment, k is the conversion coefficient, T' is the recovery time threshold, T is the node voltage recovery time, Q1” is the first current load change rate threshold after adjustment, Qmax is the maximum value of the safe range of load change rate, and Qmin is the minimum value of the safe range of load change rate.

[0088] When the negative feedback module detects that the first current load change rate threshold needs adjustment, it calculates a new load change rate threshold Q1' based on the node voltage recovery time T and a preset recovery time threshold T'. This calculation utilizes the conversion coefficient k and the ratio difference between the current recovery time and the threshold. Subsequently, the negative feedback module compares this threshold with a preset safe range Qmin to Qmax to ensure that the adjusted first current load change rate threshold Q1' is neither lower than the minimum value nor higher than the maximum value of the safe range, thereby ensuring that the power grid makes necessary adjustments under safe conditions.

[0089] By dynamically adjusting the first current load change rate threshold, the system can respond precisely to the real-time operating conditions of the power grid, improving the flexibility and adaptability of voltage management. This method ensures that even when the voltage recovery time exceeds expectations, the system can maintain voltage stability by adjusting the load change rate threshold, avoiding voltage collapse and enhancing the robustness of the power grid. Simultaneously, by limiting the threshold within a safe range, it protects power grid equipment from damage due to excessively rapid load changes, thereby extending equipment life and reducing maintenance costs.

[0090] The first current load change rate threshold is a target value for the load change rate calculated based on the current system state and some preset safety parameters. This value reflects the load change rate that the system expects to achieve given the node voltage recovery time and recovery time threshold, so as to restore the voltage to normal levels as quickly as possible without exceeding the safety range.

[0091] The conversion factor k is used in distribution network voltage management devices to calculate the load change rate threshold. It is a key parameter that affects the magnitude and response speed of the load change rate threshold adjustment. Voltage stability requirements influence the choice of k to ensure the system does not overreact to small deviations. The specific value of the conversion factor k depends on the specific needs of the distribution network and the factors mentioned above. Generally, a smaller k, between 0.1 and 1, is suitable for systems requiring gradual adjustment; a larger k, above 1, is suitable for systems requiring rapid adjustment. In this embodiment, k is set to 2, meaning the system is more sensitive to deviations in voltage recovery time, allowing for faster adjustment of the load change rate threshold to cope with voltage deviations. The device can then react quickly to voltage deviations, accelerating the voltage recovery process.

[0092] Specifically, when the negative feedback module determines that the second current load change rate threshold needs to be adjusted, it calculates the adjusted second current load change rate threshold based on the node voltage recovery time and the preset load change rate safety range.

[0093] Q2'=Q2×(1+k×(T-(T'+ΔT)) / T'), Q2”=max(min(Q2’,Qmax),Qmin),

[0094] Where Q2' is the second current load change rate threshold after one calculation, Q2 is the second current load change rate threshold before adjustment, k is the conversion coefficient, ΔT is the preset time increment, Q2” is the second current load change rate threshold after adjustment, Qmax is the maximum value of the safe range of load change rate, and Qmin is the minimum value of the safe range of load change rate.

[0095] When the negative feedback module identifies the need to adjust the second current load change rate threshold, it calculates the second current load change rate threshold Q2' for a given state using the current node voltage recovery time T, the preset recovery time threshold T', the preset time increment ΔT, and the conversion coefficient k. This calculation involves weighting the difference between the actual recovery time and the expected recovery time and its increment, and then adding it to the existing first current load change rate threshold Q2. Subsequently, to ensure the safe operation of the power grid, the negative feedback module compares the calculated threshold with the preset load change rate safety range Qmin to Qmax, and takes the maximum value within this range as the adjusted second current load change rate threshold Q2.

[0096] The adjustment strategy of the negative feedback module provides an adaptive load management mechanism for the distribution network, which can dynamically adjust the load change rate threshold according to the actual voltage recovery situation. This dynamic adjustment helps optimize the grid's response speed, enabling it to more effectively address the problem of voltage recovery delay. By keeping the threshold within a safe range, this mechanism not only ensures the stability of the grid but also avoids equipment damage or power outages caused by excessively rapid load changes.

[0097] The second current load change rate threshold is a target value for the load change rate derived from specific conditions and calculation formulas in power system voltage management devices. This value reflects the second load change rate that the system hopes to achieve under specific system recovery time conditions, so as to achieve voltage recovery or maintain system stability without exceeding safe limits.

[0098] Specifically, the data calculation module calculates the voltage deviation based on the real-time voltage and the rated voltage.

[0099] v = (V - V0) / V0,

[0100] Where v is the voltage deviation, V is the real-time voltage, and V0 is the rated voltage.

[0101] The data calculation module calculates the voltage deviation v based on the real-time monitored voltage V and the system's set rated voltage V0. The voltage deviation is derived from the formula: the difference between the real-time voltage and the rated voltage divided by the rated voltage.

[0102] Calculating voltage deviation provides the real-time voltage difference from the rated voltage, helping to detect voltage anomalies in a timely manner. Quantifying voltage deviation facilitates comparison and analysis, providing a numerical basis for voltage stability analysis, and providing accurate voltage deviation data for the anomaly detection module to help it make accurate anomaly type judgments. By calculating voltage deviation, preventive measures can be taken in advance to avoid power instability or equipment damage caused by voltage problems.

[0103] Specifically, the data calculation module calculates voltage stability indicators based on real-time voltage and real-time active power.

[0104] ,

[0105] Where s is the voltage stability index and P is the real-time active power. It is a partial derivative.

[0106] This module evaluates the sensitivity of voltage to changes in active power by taking the partial derivative of the real-time voltage V with respect to the real-time active power P. This calculation involves quantifying the ratio between the rate of change of voltage and the rate of change of active power, thereby obtaining an index of voltage stability. This index reflects the ability of voltage to remain stable when active power changes and is a key quantitative parameter for voltage stability analysis.

[0107] Voltage stability indices are derived by calculating the partial derivative of real-time voltage with respect to real-time active power. This process involves a quantitative analysis of the relationship between voltage and active power changes, thereby assessing voltage stability under active power variations. The advantage of this method lies in its ability to accurately capture the voltage's response to load changes, providing crucial information for distribution network voltage management devices. This enables the system to monitor and predict voltage stability in real time, take timely adjustment measures, and effectively prevent voltage collapse.

[0108] Specifically, the data calculation module calculates the load current change rate based on a preset time increment and the change in real-time current within the time increment.

[0109] C = ΔI / ΔT,

[0110] Where C is the load current change rate, ΔI is the change in real-time current over time increment, and ΔT is the preset time increment.

[0111] The data calculation module monitors the real-time changes in the distribution network current and divides the change in current within a preset time increment by that time increment to obtain the load current change rate.

[0112] Accurate calculation of load current change rate is crucial for timely detection and response to load fluctuations in the power grid. It can help the system prevent voltage instability and power outages, thereby improving the stability of the power grid and the reliability of power supply.

[0113] Please continue reading. Figure 4 As shown, it is the logic diagram for determining abnormal voltage deviation in this embodiment;

[0114] Specifically, the anomaly detection module compares the voltage deviation with a preset voltage deviation threshold.

[0115] If the voltage deviation is greater than or equal to the voltage deviation threshold, the anomaly detection module determines that a voltage deviation anomaly has occurred and compares the voltage stability index with the voltage stability index threshold.

[0116] If the voltage stability index is greater than or equal to the voltage stability index threshold, the anomaly detection module determines that a voltage stability anomaly has occurred.

[0117] The anomaly detection module first compares the real-time monitored voltage deviation with a preset voltage deviation threshold. When the voltage deviation reaches or exceeds this threshold, the module identifies an anomaly. Subsequently, the module further compares the voltage stability index with a preset voltage stability index threshold. If the stability index also reaches or exceeds the threshold, the module determines that the system has experienced a voltage stability anomaly.

[0118] Through continuous monitoring and assessment, distribution network voltage management devices can quickly respond to voltage anomalies, prevent voltage collapse, and ensure grid stability and power supply continuity. Furthermore, accurately identifying the type of anomaly helps implement more precise adjustment strategies, improves voltage management efficiency, and enhances the reliability of the entire power system and the user's electricity experience.

[0119] Specifically, when the anomaly detection module determines that a voltage stability anomaly has occurred, it compares the load current change rate with a load change rate threshold.

[0120] If the load current change rate is greater than the load change rate threshold, the anomaly detection module determines that a load anomaly has occurred.

[0121] In power distribution network voltage management devices, once the anomaly detection module detects an anomaly in voltage stability, it immediately assesses the load current change rate. This module compares the real-time calculated load current change rate with a preset load change rate threshold. If the current load current change rate exceeds the set threshold, the module determines that a load anomaly exists in the system.

[0122] The load anomaly detection mechanism allows the system to further confirm whether there are load problems after detecting voltage stability anomalies, thereby enabling a more comprehensive assessment of the grid's health. Once a load anomaly is identified, the system can take corresponding measures, such as adjusting generation, reallocating load, or implementing demand-side management strategies, to alleviate grid pressure, prevent voltage collapse, and ensure the stability and reliability of power supply.

[0123] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0124] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A voltage management device for power distribution networks, characterized in that, include: The data acquisition module is used to collect real-time voltage, real-time current, real-time active power, and node voltage recovery time at each node of the distribution network. The data calculation module is connected to the data acquisition module and is used to calculate voltage deviation, voltage stability index and load current change rate based on real-time voltage, real-time current, real-time active power, rated voltage and preset time increment. An anomaly determination module, connected to the data calculation module, is used to determine the type of anomaly based on the voltage deviation, the voltage stability index, the load current change rate, a preset voltage deviation threshold, a preset voltage stability index threshold, and a preset standard current load change rate threshold. When an anomaly is determined to occur, the anomaly determination module determines the degree of load anomaly based on the load current change rate, a first current load change rate threshold, and a second current load change rate threshold, and makes corresponding adjustments based on the degree of load anomaly. The negative feedback module is connected to the data acquisition module and the anomaly determination module respectively. It is used to make a determination based on the node voltage recovery time, the preset target node voltage recovery time, and the preset time increment. When the negative feedback module determines that the first current load change rate threshold needs to be adjusted, it adjusts the first current load change rate threshold based on the node voltage recovery time, the target node voltage recovery time, and the preset load change rate safety range. When the negative feedback module determines that the second current load change rate threshold needs to be adjusted, it adjusts the second current load change rate threshold based on the node voltage recovery time, the target node voltage recovery time, the preset time increment, and the preset load change rate safety range. When the anomaly detection module determines that a load anomaly has occurred, it compares the load current change rate with a first current load change rate threshold and a second current load change rate threshold, respectively. If the load current change rate is less than the first current load change rate threshold, the anomaly detection module determines it as a slight change anomaly and reduces the load on non-critical parts. If the load current change rate is greater than or equal to the first current load change rate threshold and less than the second current load change rate threshold, the anomaly detection module determines it as a moderate change anomaly and issues a demand response signal. If the load current change rate is greater than the second current load change rate threshold, the anomaly detection module determines it to be a drastic change anomaly, disconnects the power supply and issues an alarm. The negative feedback module makes a determination based on the node voltage recovery time, recovery time threshold, and preset time increment collected by the data acquisition module. If the node voltage recovery time is greater than or equal to the recovery time threshold, and less than the sum of the recovery time threshold and the preset time increment, the negative feedback module determines that the first current load change rate threshold needs to be adjusted. If the node voltage recovery time is greater than or equal to the sum of the recovery time threshold and the preset time increment, the negative feedback module determines that the second current load change rate threshold needs to be adjusted.

2. The power distribution network voltage management device according to claim 1, characterized in that, When the negative feedback module determines that the first current load change rate threshold needs to be adjusted, it calculates the adjusted first current load change rate threshold based on the node voltage recovery time and the preset load change rate safety range. Q1'=Q1×(1+k×(T-T') / T'), Q1”=max(min(Q1’,Qmax),Qmin), Where Q1' is the first current load change rate threshold after one calculation, Q1 is the first current load change rate threshold before adjustment, k is the conversion coefficient, T' is the recovery time threshold, T is the node voltage recovery time, Q1” is the first current load change rate threshold after adjustment, Qmax is the maximum value of the safe range of load change rate, and Qmin is the minimum value of the safe range of load change rate.

3. The power distribution network voltage management device according to claim 2, characterized in that, When the negative feedback module determines that the second current load change rate threshold needs to be adjusted, it calculates the adjusted second current load change rate threshold based on the node voltage recovery time, the preset load change rate safety range, and the preset time increment. Q2'=Q2×(1+k×(T-(T'+ΔT)) / T'), Q2”=max(min(Q2’,Qmax),Qmin), Where Q2' is the second current load change rate threshold after one calculation, Q2 is the second current load change rate threshold before adjustment, k is the conversion coefficient, ΔT is the preset time increment, Q2” is the second current load change rate threshold after adjustment, Qmax is the maximum value of the safe range of load change rate, and Qmin is the minimum value of the safe range of load change rate.

4. The power distribution network voltage management device according to claim 3, characterized in that, The data calculation module calculates the voltage deviation based on the real-time voltage and the rated voltage. v = (V - V0) / V0, Where v is the voltage deviation, V is the real-time voltage, and V0 is the rated voltage.

5. The power distribution network voltage management device according to claim 4, characterized in that, The data calculation module calculates voltage stability indicators based on real-time voltage and real-time active power. ， Where s is the voltage stability index and P is the real-time active power. It is a partial derivative.

6. The power distribution network voltage management device according to claim 5, characterized in that, The data calculation module calculates the load current change rate based on a preset time increment and the change in real-time current within the time increment. C = ΔI / ΔT, Where C is the load current change rate, ΔI is the change in real-time current over time increment, and ΔT is the preset time increment.

7. The power distribution network voltage management device according to claim 6, characterized in that, The anomaly detection module compares the voltage deviation with a preset voltage deviation threshold. If the voltage deviation is greater than or equal to the voltage deviation threshold, the anomaly detection module determines that a voltage deviation anomaly has occurred and compares the voltage stability index with the voltage stability index threshold. If the voltage stability index is greater than or equal to the voltage stability index threshold, the anomaly detection module determines that a voltage stability anomaly has occurred.

8. The power distribution network voltage management device according to claim 7, characterized in that, When the anomaly detection module determines that a voltage stability anomaly has occurred, it compares the load current change rate with a standard current load change rate threshold. If the rate of change of load current is greater than the standard current load change rate threshold, the anomaly detection module determines that a load anomaly has occurred.

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