A power distribution grid energy storage system fault detection method comprising a flow battery

Abstract

The application provides a power distribution network energy storage system fault detection method comprising the following steps: step (1), collecting working information of the flow battery; step (2), judging the energy storage system according to the charge-discharge voltage, and if there is an anomaly, an alarm is sent; if there is no anomaly, step (3) is entered; step (3), calculating the actual value of the energy storage system capacity; step (4), judging whether the energy storage system has an anomaly or cannot meet the demand according to the actual value of the capacity, and if yes, an alarm is sent; if no, step (5) is entered; step (5), calculating the charge-discharge efficiency of the energy storage system; and step (6), judging whether the energy storage system has an anomaly according to the charge-discharge efficiency, and if yes, an alarm is sent. The application provides a power distribution network energy storage system fault detection method, which can improve the working reliability of the energy storage system, and further ensure the stability of the power grid.

Description

Technical Field

[0001] This invention belongs to the field of energy storage system testing technology, and specifically relates to a fault detection method for a distribution network energy storage system including a flow battery. Background Technology

[0002] Currently, the world is undergoing an energy transition and technological revolution characterized by low-carbon, zero-carbon, and negative-carbon technologies. New energy sources such as wind and solar power are developing rapidly. However, large-scale utilization of new energy power generation still faces challenges such as intermittency, instability, and spatial dispersion. If not properly managed, the unstable power generated by new energy sources directly connected to the grid will put enormous pressure on the grid stability and may even lead to grid accidents. In order to protect the consumption of traditional energy sources and protect the environment, it is necessary to use energy storage systems for power distribution.

[0003] This invention proposes a fault detection method for a power distribution network energy storage system incorporating a flow battery. The method collects the operating information of the flow battery and calculates the characteristic values ​​of the energy storage system's voltage efficiency, actual capacity, and charge / discharge efficiency as characteristic values ​​for anomaly detection. This ensures the accuracy of anomaly detection, thereby guaranteeing a stable and reliable power output from the power distribution network energy storage system and ultimately ensuring grid stability. Summary of the Invention

[0004] This invention provides a fault detection method for a power grid energy storage system including a flow battery, which can improve the operational reliability of the energy storage system and thus ensure the stability of the power grid.

[0005] Specifically, this invention relates to a fault detection method for a power distribution network energy storage system including a flow battery, the fault detection method comprising the following steps: Step (1): Collect the working information of the flow battery, including charging and discharging current, charging and discharging voltage, charging and discharging time, and battery body temperature; Step (2): Based on the charging and discharging voltage, the energy storage system is fault-determined. If an abnormality is found, an alarm is issued; if no abnormality is found, proceed to step (3). Step (3): Calculate the actual capacity of the energy storage system; Step (4): Determine whether the energy storage system is abnormal or unable to meet the demand based on the actual capacity value. If yes, issue an alarm; otherwise, proceed to step (5). Step (5): Calculate the charge and discharge efficiency of the energy storage system; Step (6): Determine whether there is an abnormality in the energy storage system based on the charging and discharging efficiency. If so, issue an alarm.

[0006] Furthermore, the specific method for fault diagnosis of the energy storage system based on the charging and discharging voltage in step (2) is as follows: (21) Determine whether the charging and discharging voltage is within the voltage reference range. If yes, there is an abnormality in the energy storage system; if not, proceed to step (22). (22) Calculate the average charging voltage and average discharging voltage over a day; (23) Calculate the characteristic value of voltage efficiency of the energy storage system; (24) Determine whether the voltage efficiency characteristic value is less than the voltage efficiency characteristic value reference value. If so, there is an abnormality in the energy storage system.

[0007] Furthermore, the specific algorithm for calculating the voltage efficiency characteristic value in step (23) is as follows:

[0008] in For discharge voltage, For charging voltage, The duration of discharge within one day. The duration of charging within a day, The average value of the discharge voltage. The average value of the charging voltage.

[0009] Furthermore, the specific method for calculating the actual capacity of the energy storage system in step (3) is as follows:

[0010] in The sampling period is The charging and discharging current, This represents the initial capacity of the energy storage system.

[0011] Furthermore, the specific method for determining whether the energy storage system has any abnormalities or cannot meet the demand based on the actual capacity value in step (4) is as follows: (41) Determine whether the actual capacity value is greater than the demand load. If yes, proceed to step (42); if not, the grid demand cannot be met. (42) Determine whether the actual capacity value is less than the capacity threshold. If so, there is an anomaly in the energy storage system.

[0012] Furthermore, the capacity threshold is selected based on the battery body temperature.

[0013] Furthermore, the specific method for calculating the charge and discharge efficiency of the energy storage system in step (5) is as follows:

[0014] in This represents the initial charge value of the energy storage system. This represents the final charge value of the energy storage system. Energy storage system charge / discharge duration The charging and discharging power of the energy storage system.

[0015] Furthermore, the specific method for determining whether there is an anomaly in the energy storage system based on the charging and discharging efficiency in step (6) is as follows: Determine whether the charge / discharge efficiency is less than the reference value. If so, the energy storage system is abnormal.

[0016] Compared with existing technologies, the beneficial effects are: the fault detection method for the distribution network energy storage system collects the working information of the flow battery, calculates the characteristic value of the energy storage system voltage efficiency, the actual value of the energy storage system capacity, and the charge and discharge efficiency as characteristic values ​​for anomaly judgment, ensuring the accuracy of anomaly detection, and thus ensuring that the distribution network energy storage system outputs stable and reliable electrical energy. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a flowchart illustrating the fault detection method for a power distribution network energy storage system including a flow battery, according to the present invention. Detailed Implementation

[0018] The following detailed description, with reference to the accompanying drawings and preferred embodiments, illustrates a specific implementation of the fault detection method for a distribution network energy storage system incorporating a flow battery according to the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are merely illustrative of the present invention and not intended to limit the scope of protection of the present invention.

[0019] like Figure 1 As shown, the fault detection method for distribution network energy storage system of the present invention includes the following steps: Step (1): Collect the working information of the flow battery, including charging and discharging current, charging and discharging voltage, charging and discharging time, and battery body temperature; Step (2): Based on the charging and discharging voltage, the energy storage system is fault-determined. If an abnormality is found, an alarm is issued; if no abnormality is found, proceed to step (3). Step (3): Calculate the actual capacity of the energy storage system; Step (4): Determine whether the energy storage system is abnormal or unable to meet the demand based on the actual capacity value. If yes, issue an alarm; otherwise, proceed to step (5). Step (5): Calculate the charge and discharge efficiency of the energy storage system; Step (6): Determine whether there is an abnormality in the energy storage system based on the charging and discharging efficiency. If so, issue an alarm.

[0020] The specific method for fault diagnosis of the energy storage system based on the charging and discharging voltage in step (2) is as follows: (21) Determine whether the charging and discharging voltage is within the voltage reference range. If yes, there is an abnormality in the energy storage system; if not, proceed to step (22). (22) Calculate the average charging voltage and average discharging voltage over a day; (23) Calculate the characteristic value of voltage efficiency of the energy storage system; (24) Determine whether the voltage efficiency characteristic value is less than the voltage efficiency characteristic value reference value. If so, there is an abnormality in the energy storage system.

[0021] The specific algorithm for calculating the voltage efficiency characteristic value in step (23) is as follows:

[0022] in For discharge voltage, For charging voltage, The duration of discharge within one day. The duration of charging within a day, The average value of the discharge voltage. The average value of the charging voltage.

[0023] The specific method for calculating the actual capacity of the energy storage system in step (3) is as follows:

[0024] in The sampling period is The charging and discharging current, This represents the initial capacity of the energy storage system.

[0025] The specific method for determining whether the energy storage system has any abnormalities or cannot meet the demand based on the actual capacity value in step (4) is as follows: (41) Determine whether the actual capacity value is greater than the demand load. If yes, proceed to step (42); if not, the grid demand cannot be met. (42) Determine whether the actual capacity value is less than the capacity threshold. If so, there is an anomaly in the energy storage system.

[0026] Since the capacity of a battery is affected by temperature, the capacity threshold is selected based on the temperature of the battery itself.

[0027] The specific method for calculating the charge and discharge efficiency of the energy storage system in step (5) is as follows:

[0028] in This represents the initial charge value of the energy storage system. This represents the final charge value of the energy storage system. Energy storage system charge / discharge duration The charging and discharging power of the energy storage system.

[0029] The specific method for determining whether there is an abnormality in the energy storage system based on the charging and discharging efficiency in step (6) is as follows: Determine whether the charge / discharge efficiency is less than the reference value. If so, the energy storage system is abnormal.

[0030] This invention also proposes a fault detection system for a power distribution network energy storage system containing a flow battery, comprising a signal acquisition module, a control processing module, an alarm module, and a communication module. The signal acquisition module uses sampling sensors to collect operating information of the flow battery, including charging and discharging current, charging and discharging voltage, charging and discharging time, and battery body temperature. The control processing module makes control decisions for the energy storage system based on the collected information. Step (1): Based on the charging and discharging voltage, the energy storage system is fault-determined. If an abnormality is found, the alarm unit is controlled to issue an alarm; if no abnormality is found, proceed to step (2). (11) Determine whether the charging and discharging voltage is within the voltage reference range. If yes, there is an abnormality in the energy storage system; if not, proceed to step (12). (12) Calculate the average charging voltage and average discharging voltage over a day; (13) Calculate the voltage efficiency characteristic value of the energy storage system.

[0031] in For discharge voltage, For charging voltage, The duration of discharge within one day. The duration of charging within a day, The average value of the discharge voltage. The average value of the charging voltage; (14) Determine whether the voltage efficiency characteristic value is less than the voltage efficiency characteristic value reference value. If so, the energy storage system has an anomaly. Step (2): Calculate the actual capacity of the energy storage system

[0032] in The sampling period is The charging and discharging current, This represents the initial capacity of the energy storage system. Step (3): Determine whether the energy storage system is abnormal or unable to meet the demand based on the actual capacity value. If yes, issue an alarm; otherwise, proceed to step (4). (31) Determine whether the actual capacity value is greater than the demand load. If yes, proceed to step (32); if not, the grid demand cannot be met. (32) Determine whether the actual capacity value is less than the capacity threshold. If so, there is an anomaly in the energy storage system. Step (4): Calculate the charging and discharging efficiency of the energy storage system.

[0033] in This represents the initial charge value of the energy storage system. This represents the final charge value of the energy storage system. Energy storage system charge / discharge duration The charging and discharging power of the energy storage system; Step (5): Determine whether there is an abnormality in the energy storage system based on the charging and discharging efficiency: Determine whether the charging and discharging efficiency is less than the charging and discharging efficiency reference value. If so, there is an abnormality in the energy storage system. If so, the control alarm unit issues an alarm.

[0034] The communication module uses wireless communication technology to send the detection results of the power distribution network energy storage system fault detection system to the remote control center.

[0035] Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention and not intended to limit it. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the specific embodiments of the present invention, but such modifications or alterations are all within the scope of protection of the pending claims.

Claims

1. A fault detection method for a power distribution network energy storage system including a flow battery, characterized in that, The fault detection method for the distribution network energy storage system includes the following steps: Step (1): Collect the working information of the flow battery, including charging and discharging current, charging and discharging voltage, charging and discharging time, and battery body temperature; Step (2): Based on the charging and discharging voltage, the energy storage system is fault-determined. If an abnormality is found, an alarm is issued; if no abnormality is found, proceed to step (3). Step (3): Calculate the actual capacity of the energy storage system; Step (4): Determine whether the energy storage system is abnormal or unable to meet the demand based on the actual capacity value. If yes, issue an alarm; otherwise, proceed to step (5). Step (5): Calculate the charge and discharge efficiency of the energy storage system; Step (6): Determine whether there is an abnormality in the energy storage system based on the charging and discharging efficiency. If so, issue an alarm.

2. The fault detection method for a power distribution network energy storage system including a flow battery according to claim 1, characterized in that, The specific method for fault diagnosis of the energy storage system based on the charging and discharging voltage in step (2) is as follows: (21) Determine whether the charging and discharging voltage is within the voltage reference range. If yes, there is an abnormality in the energy storage system; if not, proceed to step (22). (22) Calculate the average charging voltage and average discharging voltage over a day; (23) Calculate the characteristic value of voltage efficiency of the energy storage system; (24) Determine whether the voltage efficiency characteristic value is less than the voltage efficiency characteristic value reference value. If so, there is an abnormality in the energy storage system.

3. The fault detection method for a power distribution network energy storage system including a flow battery according to claim 2, characterized in that, The specific algorithm for calculating the voltage efficiency characteristic value in step (23) is as follows: ， in For discharge voltage, For charging voltage, The duration of discharge within one day. The duration of charging within a day, The average value of the discharge voltage. The average value of the charging voltage.

4. The fault detection method for a power distribution network energy storage system including a flow battery according to claim 3, characterized in that, The specific method for calculating the actual capacity of the energy storage system in step (3) is as follows: ， in The sampling period is The charging and discharging current, This represents the initial capacity of the energy storage system.

5. A fault detection method for a power distribution network energy storage system including a flow battery according to claim 4, characterized in that, The specific method for determining whether the energy storage system has any abnormalities or cannot meet the demand based on the actual capacity value in step (4) is as follows: (41) Determine whether the actual capacity value is greater than the demand load. If yes, proceed to step (42); if not, the grid demand cannot be met. (42) Determine whether the actual capacity value is less than the capacity threshold. If so, there is an anomaly in the energy storage system.

6. The fault detection method for a power distribution network energy storage system including a flow battery according to claim 5, characterized in that, The capacity threshold is selected based on the battery body temperature.

7. A fault detection method for a power distribution network energy storage system including a flow battery according to claim 6, characterized in that, The specific method for calculating the charge and discharge efficiency of the energy storage system in step (5) is as follows: ， in This represents the initial charge value of the energy storage system. This represents the final charge value of the energy storage system. Energy storage system charging / discharging time The charging and discharging power of the energy storage system.

8. The fault detection method for a power distribution network energy storage system including a flow battery according to claim 7, characterized in that, The specific method for determining whether there is an abnormality in the energy storage system based on the charging and discharging efficiency in step (6) is as follows: determine whether the charging and discharging efficiency is less than the charging and discharging efficiency reference value. If so, there is an abnormality in the energy storage system.

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