Optimization control method and system for micro-grid energy storage

Abstract

The invention belongs to the technical field of micro-grid energy storage, and particularly relates to a micro-grid energy storage-oriented optimization control method and system, and the method comprises the steps: carrying out the real-time monitoring of the charging and discharging efficiency of an energy storage system, carrying out the real-time analysis and processing according to the sudden change of the charging and discharging efficiency, and achieving the real-time monitoring of the energy storage system. Whether the energy storage system is powered off or regulated is controlled, so that the operation safety of the energy storage system is ensured; according to the method, firstly, the influence degree generated when the charging and discharging efficiency of the energy storage system exceeds a first threshold value is analyzed to obtain a node value, the regulation and control time of the energy storage system is determined according to the node value, and based on the regulation and control time point of the energy storage system, a charging and discharging module of the energy storage system is regulated and controlled to enable the charging and discharging efficiency to enter a safe area; and the charging and discharging efficiency of the energy storage system is ensured to be in a relative safety interval range, so that the energy storage system can continuously and stably work.

Description

Technical Field

[0001] The present invention belongs to the technical field of microgrid energy storage, and specifically relates to an optimization control method and system for microgrid energy storage. Background Art

[0002] Microgrid is a flexible and reliable way of power supply. The energy storage system in it is a key link in energy balance and regulation. Its control strategy directly affects the stability and economy of the microgrid.

[0003] The control strategy of the existing microgrid energy storage system is not perfect enough. It is impossible to monitor the charging and discharging efficiency of the energy storage system in real time, and it is impossible to perform real-time analysis and processing based on possible sudden changes in the charging and discharging efficiency, and determine whether to power off or control the energy storage system. It is impossible to ensure the safety of the operation of the energy storage system.

[0004] To this end, the present invention provides an optimization control method and system for microgrid energy storage. Summary of the invention

[0005] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0006] The technical solution adopted by the present invention to solve the technical problem is: an optimization control method for microgrid energy storage described in the present invention comprises: Data collection: sensors and monitoring equipment installed in the microgrid are used to collect microgrid operation data in real time, including energy storage status data. According to the collected energy storage status data, the state of the energy storage system is judged; According to the discrimination result, based on the charging and discharging efficiency data during the operation of the energy storage system, the variation value BYZ of the energy storage system is obtained, the variation value is analyzed, and a control signal is generated; Based on the control signal, the collection cycle is set, and the inclination value at the current moment and the inclination value at the starting moment are determined according to the charge and discharge efficiency curve. Then, the variation value of the energy storage system is obtained based on the inclination value at the current moment and the inclination value at the starting moment, and the variation value is compared with the variation threshold of the current energy storage system to obtain a shutdown signal or a control signal; Based on the control signal, the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change are obtained, and the node value is obtained based on the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change, and the control time of the energy storage system is determined according to the node value; Based on the control time point of the energy storage system, the charging and discharging modules of the energy storage system are regulated to bring the charging and discharging efficiency into a safe area.

[0007] Preferably, the state of the energy storage system is determined based on the collected energy storage state data, specifically: Obtain the operating time and charge-discharge efficiency of the energy storage system, build a two-dimensional model of the energy storage system with time as the X-axis and charge-discharge efficiency as the Y-axis, substitute the real-time charge-discharge efficiency into the two-dimensional model, and draw it into a speed curve; Wherein, in the two-dimensional model of the energy storage system, a first threshold and a second threshold are set, and the first threshold is smaller than the second threshold; Draw a straight line parallel to the X-axis with the first threshold and the second threshold respectively, and mark them as the first threshold line and the second threshold line respectively. The area below the first threshold line is the safe area, and the area between the first threshold line and the second threshold line is marked as the control area.

[0008] Preferably, the state of the energy storage system is determined as follows: Obtain the charging and discharging efficiency at the start time and the current charging and discharging efficiency of the energy storage system during operation; perform regional discrimination on the current charging and discharging efficiency; If the current charging and discharging efficiency is in the safe area, it indicates that the current energy storage system is working normally and generates a normal working signal; If the current charging and discharging efficiency is in the control area, it indicates that the current energy storage system is in an abnormal state and a control signal is generated.

[0009] Preferably, the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change are obtained, specifically: Set the collection cycle, and determine the inclination angle value at the current moment and the inclination angle value at the start moment according to the charge and discharge efficiency curve; Calculate the difference between the current inclination value and the inclination value at the start time to obtain the change difference BC; obtain the sum of the current inclination value and the inclination value at the start time to obtain the inclination sum QH; through the formula The variation value BYZ of the energy storage system is obtained, where a1 and a2 are preset proportional coefficients, and a1+a2=1, and a1 and a2 respectively represent the influence of the change difference and the inclination angle on the variation value.

[0010] Preferably, the variation value BYZ of the energy storage system at the current moment is compared with the variation threshold of the current energy storage system; specifically: If the variation value BYZ of the energy storage system at the current moment is greater than the variation threshold of the current energy storage system, it means that the current charging and discharging efficiency of the energy storage system has undergone a large growth change during the acquisition cycle, and it has entered the control area from the safe area with a large charging and discharging efficiency, generating a shutdown signal; If the variation value BYZ of the energy storage system at the current moment is less than or equal to the variation threshold of the current energy storage system, it means that the charging and discharging efficiency of the energy storage system changes with a small increase in the current period, and enters the control area from the safe area with a small charging and discharging efficiency, generating a control signal.

[0011] Preferably, the specific method of obtaining the node value is: After receiving the control signal, the charging and discharging efficiency of the energy storage system is continuously detected to obtain the abnormality degree value of the charging and discharging efficiency and the abnormality degree value of the change, and the abnormality degree value of the charging and discharging efficiency and the abnormality degree value of the change are added and summed to obtain the node value; Preferably, the specific method for obtaining the regulation time of the energy storage system is: Compare the node value with a preset node threshold; If the node value is less than the preset node threshold, a continuous operation signal of the energy storage system is generated; If the node value is greater than or equal to the preset node threshold, an immediate control signal is generated, and the signal generation time point is used as the energy storage system control time point.

[0012] Preferably, the abnormal degree value of the charge and discharge efficiency is obtained in the following manner: Mark the time from the start of the anomaly to the current time as the detection period; Obtain the charge and discharge efficiency at each time node within the detection period, perform difference calculation on the first threshold value, and obtain the efficiency offset value at each time node; Ratios of all efficiency offset values ​​to the maximum rated offset value are calculated respectively, and then the average of the ratios is obtained to obtain the abnormality degree value of the charge and discharge efficiency; wherein the maximum rated offset value is the difference between the first threshold value and the second threshold value.

[0013] Preferably, the specific method of obtaining the abnormal change degree value is: The charging and discharging efficiency of all time nodes within the detection period is obtained, and the abnormal degree value of the change is calculated by the variance calculation formula.

[0014] An optimization control system for microgrid energy storage, comprising: Data acquisition module: collects microgrid operation data in real time through sensors and monitoring equipment installed in the microgrid, where the microgrid operation data includes energy storage status data; Identification module: Identify the state of the energy storage system based on the collected energy storage state data; Output module: According to the judgment result, based on the charging and discharging efficiency data of the energy storage system during operation, obtain the variation value BYZ of the energy storage system, analyze the variation value, and generate a control signal; Processing module: Based on the control signal, the collection cycle is set, and the inclination value at the current moment and the inclination value at the starting moment are determined according to the charge and discharge efficiency curve. Then, the variation value of the energy storage system is obtained based on the inclination value at the current moment and the inclination value at the starting moment, and the variation value is compared with the variation threshold of the current energy storage system to obtain a shutdown signal or a control signal; Determination module: based on the control signal, obtain the abnormal degree value of charge and discharge efficiency and the abnormal degree value of change, analyze and obtain the node value based on the abnormal degree value of charge and discharge efficiency and the abnormal degree value of change, and determine the control time of the energy storage system according to the node value; Control module: Based on the control time point of the energy storage system, the charging and discharging modules of the energy storage system are controlled to bring the charging and discharging efficiency into a safe area.

[0015] The beneficial effects of the present invention are as follows: 1. The optimization control method and system for microgrid energy storage described in the present invention monitors the charging and discharging efficiency of the energy storage system in real time, performs real-time analysis and processing according to the sudden changes in the charging and discharging efficiency, controls whether the energy storage system is powered off or regulated, and ensures the safety of the operation of the energy storage system. 2. The optimization control method and system for microgrid energy storage described in the present invention obtains the abnormality degree value and the change abnormality degree value of the charging and discharging efficiency, analyzes the abnormality degree value and the change abnormality degree value to obtain the node value, determines the regulation time of the energy storage system according to the node value, and regulates the charging and discharging module of the energy storage system based on the regulation time point of the energy storage system to make the charging and discharging efficiency enter a safe area; the present invention first analyzes the degree of influence caused when the charging and discharging efficiency of the energy storage system exceeds a first threshold value to obtain the node value, determines the regulation time of the energy storage system according to the node value, and regulates the charging and discharging module of the energy storage system based on the regulation time point of the energy storage system to make the charging and discharging efficiency enter a safe area; ensures that the charging and discharging efficiency of the energy storage system is within a safe range, so that the energy storage system can work continuously and stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings.

[0017] Figure 1 It is a method flow chart of an optimization control method for microgrid energy storage of the present invention; Figure 2 It is a principle block diagram of an optimization control system for microgrid energy storage of the present invention. DETAILED DESCRIPTION

[0018] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0019] Example 1 An optimization control method for microgrid energy storage, characterized by: comprising: Step 1: Data collection: collect microgrid operation data in real time through sensors and monitoring equipment installed in the microgrid, where the microgrid operation data includes energy storage status data; Step 2: According to the collected energy storage status data, the energy storage system status is judged, specifically: In some embodiments, the energy storage state data is the operating time and the charge and discharge efficiency. The operating time and the charge and discharge efficiency of the energy storage system are obtained, and a two-dimensional model of the energy storage system is constructed with time as the X-axis and the charge and discharge efficiency as the Y-axis. The real-time charge and discharge efficiency is substituted into the two-dimensional model and plotted into a speed curve. In the two-dimensional model of the energy storage system, a first threshold and a second threshold are set, and the first threshold is less than the second threshold; the first threshold and the second threshold are both empirical values, which are set by the staff according to experience; Draw a straight line parallel to the X-axis with the first threshold and the second threshold respectively, and mark them as the first threshold line and the second threshold line respectively, and mark the area below the first threshold line as the safe area, and the area between the first threshold line and the second threshold line as the control area; It should be noted that when the energy storage system is in the safe area, it means that the charging and discharging efficiency of the energy storage system is in the normal range, the operating status of the energy storage system is in a normal state, no abnormal problems will occur, and it can continue to work; when the charging and discharging efficiency of the energy storage system is in the control area, it means that the charging and discharging efficiency of the energy storage system is abnormal, the operating status of the energy storage system is abnormal, and the charging and discharging of the energy storage system needs to be controlled.

[0020] Step 3: Based on the charging and discharging efficiency data of the energy storage system during operation, obtain the variation value BYZ of the energy storage system, analyze the variation value, and generate a control signal; wherein the control signal includes a shutdown signal and a regulation signal; In some embodiments, the charge and discharge efficiency at the start time of the energy storage system operation and the current charge and discharge efficiency are obtained; the current charge and discharge efficiency is regionally determined; If the current charging and discharging efficiency is in the safe area, it indicates that the current energy storage system is working normally and generates a normal working signal; If the current charging and discharging efficiency is in the control area, it indicates that the current energy storage system is in an abnormal state and a control signal is generated; Step 4: Based on the control signal, set the collection period, and determine the inclination angle value at the current moment and the inclination angle value at the start moment according to the charge and discharge efficiency curve; Calculate the difference between the current inclination value and the inclination value at the start time to obtain the change difference BC; obtain the sum of the current inclination value and the inclination value at the start time to obtain the inclination sum QH; through the formula The variation value BYZ of the energy storage system is obtained, where a1 and a2 are preset proportional coefficients, and a1+a2=1, and a1 and a2 respectively represent the influence of the change difference and the inclination angle on the variation value.

[0021] Compare the variation value BYZ of the energy storage system at the current moment with the variation threshold of the current energy storage system; the variation threshold of the current energy storage system is an empirical value, which is set by the staff based on experience; If the variation value BYZ of the energy storage system at the current moment is greater than the variation threshold of the current energy storage system, it means that the current charging and discharging efficiency of the energy storage system has undergone a large growth change during the acquisition cycle, and it has entered the control area from the safe area with a large charging and discharging efficiency, generating a shutdown signal; If the variation value BYZ of the energy storage system at the current moment is less than or equal to the variation threshold of the current energy storage system, it means that the charging and discharging efficiency of the energy storage system changes with a small increase in the current period, and enters the control area from the safe area with a small charging and discharging efficiency, and generates a control signal; It is understandable that the inclination value of the energy storage system at the current moment changes greatly in a short period of time, resulting in the inability to effectively control the charging and discharging power, causing the charging and discharging module of the energy storage system to malfunction.

[0022] The variation value is the degree of change of the inclination value of the charge-discharge efficiency curve from the beginning of the collection period to the current moment. The greater the degree of change, the greater the change trend in the current time period. The inclination sum value is recorded as the overall level of the inclination value in the collection period. The greater the change, the greater the change trend of the charge-discharge efficiency curve in the collection period.

[0023] The present invention monitors the charging and discharging efficiency of the energy storage system in real time, performs real-time analysis and processing according to possible sudden changes in the charging and discharging efficiency, controls whether the energy storage system is powered off or regulated, and ensures the safety of the operation of the energy storage system.

[0024] Example 2 Step 5: Based on the control signal, obtain the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change, analyze and obtain the node value based on the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change, and determine the control time of the energy storage system according to the node value; In some embodiments, after receiving the control signal, the charge and discharge efficiency of the energy storage system is continuously detected to obtain the abnormality degree value of the charge and discharge efficiency and the abnormality degree value of the change, and the abnormality degree value of the charge and discharge efficiency and the abnormality degree value of the change are added and summed to obtain the node value; Compare the node value with a preset node threshold; If the node value is less than the preset node threshold, a continuous operation signal of the energy storage system is generated; If the node value is greater than or equal to the preset node threshold, an immediate control signal is generated, and the signal generation time point is used as the energy storage system control time point.

[0025] It should be noted that the continuous working signal of the energy storage system indicates that when the charging and discharging efficiency of the energy storage system is higher than the first threshold, the degree of change and continuity of the charging and discharging efficiency is not high, and has not reached the warning level that the energy storage system can withstand. At this time, the energy storage system can continue to work and will not cause harm to the entire energy storage system; on the contrary, when the charging and discharging efficiency of the energy storage system is higher than the first threshold, the degree of change and continuity of the charging and discharging efficiency is too high, exceeding the warning level that the energy storage system can withstand. At this time, if the energy storage system continues to work, it will cause harm to the entire energy storage system. Therefore, timely regulation is required to avoid causing greater damage to the energy storage system.

[0026] Exemplarily, the abnormal degree value of the charge and discharge efficiency is obtained in the following manner: Mark the time from the start of the anomaly to the current time as the detection period; Obtain the charge and discharge efficiency at each time node within the detection period, perform difference calculation on the first threshold value, and obtain the efficiency offset value at each time node; Ratios of all efficiency offset values ​​to the maximum rated offset value are calculated respectively, and then the average of the ratios is obtained to obtain the abnormality degree value of the charge and discharge efficiency; wherein the maximum rated offset value is the difference between the first threshold value and the second threshold value.

[0027] The specific method for obtaining the abnormal degree value of the change is: The charging and discharging efficiency of all time nodes within the detection period is obtained, and the abnormal degree value of the change is calculated by the variance calculation formula.

[0028] Step 6: Based on the energy storage system control time point, the charging and discharging modules of the energy storage system are controlled to bring the charging and discharging efficiency into a safe area.

[0029] The technical solution in the embodiment of the present invention is: based on the control signal, the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change are obtained, the node value is obtained based on the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change, the control time of the energy storage system is determined according to the node value, and the charge and discharge module of the energy storage system is controlled based on the control time point of the energy storage system, so that the charge and discharge efficiency enters the safe area; the present invention first analyzes the impact degree generated when the charge and discharge efficiency of the energy storage system exceeds the first threshold value to obtain the node value, determines the control time of the energy storage system according to the node value, and controls the charge and discharge module of the energy storage system based on the control time point of the energy storage system, so that the charge and discharge efficiency enters the safe area; ensure that the charge and discharge efficiency of the energy storage system is within the range relative to the safe interval, so that the energy storage system can work continuously and stably.

[0030] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An optimization control method for microgrid energy storage, characterized in that: include Data collection: sensors and monitoring equipment installed in the microgrid are used to collect microgrid operation data in real time, including energy storage status data. According to the collected energy storage status data, the state of the energy storage system is judged; According to the discrimination result, based on the charging and discharging efficiency data during the operation of the energy storage system, the variation value BYZ of the energy storage system is obtained, the variation value is analyzed, and a control signal is generated; Based on the control signal, the collection cycle is set, and the inclination value at the current moment and the inclination value at the starting moment are determined according to the charge and discharge efficiency curve. Then, the variation value of the energy storage system is obtained based on the inclination value at the current moment and the inclination value at the starting moment, and the variation value is compared with the variation threshold of the current energy storage system to obtain a shutdown signal or a control signal; Based on the control signal, the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change are obtained, and the node value is obtained based on the abnormal degree value of the charge and discharge efficiency and the abnormal degree value of the change, and the control time of the energy storage system is determined according to the node value; Based on the control time point of the energy storage system, the charging and discharging modules of the energy storage system are regulated to bring the charging and discharging efficiency into a safe area.

2. The optimization control method for microgrid energy storage according to claim 1, characterized in that: According to the collected energy storage status data, the energy storage system status is judged, specifically: Obtain the operating time and charge-discharge efficiency of the energy storage system, build a two-dimensional model of the energy storage system with time as the X-axis and charge-discharge efficiency as the Y-axis, substitute the real-time charge-discharge efficiency into the two-dimensional model, and draw it into a speed curve; Wherein, in the two-dimensional model of the energy storage system, a first threshold and a second threshold are set, and the first threshold is smaller than the second threshold; Draw a straight line parallel to the X-axis with the first threshold and the second threshold respectively, and mark them as the first threshold line and the second threshold line respectively. The area below the first threshold line is the safe area, and the area between the first threshold line and the second threshold line is marked as the control area.

3. The optimization control method for microgrid energy storage according to claim 2, characterized in that: The state of the energy storage system is determined as follows: Obtain the charge and discharge efficiency at the start time and the current charge and discharge efficiency of the energy storage system during operation; perform regional discrimination on the current charge and discharge efficiency; If the current charging and discharging efficiency is in the safe area, it indicates that the current energy storage system is working normally and generates a normal working signal; If the current charging and discharging efficiency is in the control area, it indicates that the current energy storage system is in an abnormal state and a control signal is generated.

4. The optimization control method for microgrid energy storage according to claim 1, characterized in that: Obtain the abnormal degree value of charge and discharge efficiency and the abnormal degree value of change, specifically: Set the collection cycle, and determine the inclination angle value at the current moment and the inclination angle value at the start moment according to the charge and discharge efficiency curve; Calculate the difference between the current inclination value and the inclination value at the start time to obtain the change difference BC; obtain the sum of the current inclination value and the inclination value at the start time to obtain the inclination sum QH; through the formula The variation value BYZ of the energy storage system is obtained, where a1 and a2 are preset proportional coefficients, and a1+a2=1, and a1 and a2 respectively represent the influence of the variation difference and the inclination angle on the variation value.

5. The optimization control method for microgrid energy storage according to claim 4, characterized in that: Compare the variation value BYZ of the energy storage system at the current moment with the variation threshold of the current energy storage system; specifically: If the variation value BYZ of the energy storage system at the current moment is greater than the variation threshold of the current energy storage system, it means that the current charging and discharging efficiency of the energy storage system has undergone a large growth change during the acquisition cycle, and it has entered the control area from the safe area with a large charging and discharging efficiency, generating a shutdown signal; If the variation value BYZ of the energy storage system at the current moment is less than or equal to the variation threshold of the current energy storage system, it means that the charging and discharging efficiency of the energy storage system changes with a small increase in the current period, and enters the control area from the safe area with a small charging and discharging efficiency, generating a control signal.

6. The optimization control method for microgrid energy storage according to claim 1, characterized in that: The specific way to obtain the node value is: After receiving the control signal, the charging and discharging efficiency of the energy storage system is continuously detected to obtain the abnormal degree value of the charging and discharging efficiency and the abnormal degree value of the change, and the abnormal degree value of the charging and discharging efficiency and the abnormal degree value of the change are added and summed to obtain the node value.

7. The optimization control method for microgrid energy storage according to claim 6, characterized in that: The specific method for obtaining the control time of the energy storage system is as follows: Compare the node value with a preset node threshold; If the node value is less than the preset node threshold, a continuous operation signal of the energy storage system is generated; If the node value is greater than or equal to the preset node threshold, an immediate control signal is generated, and the signal generation time point is used as the energy storage system control time point.

8. The optimization control method for microgrid energy storage according to claim 6, characterized in that: The method for obtaining the abnormal degree value of charge and discharge efficiency is as follows: Mark the time from the start of the anomaly to the current time as the detection period; Obtain the charge and discharge efficiency at each time node within the detection period, perform difference calculation on the first threshold value, and obtain the efficiency offset value at each time node; Calculate the ratios of all efficiency offset values ​​to the maximum rated offset value, and then obtain the average of the ratios to obtain the abnormality degree value of the charge and discharge efficiency; The maximum rated offset value is the difference between the first threshold and the second threshold.

9. The optimization control method for microgrid energy storage according to claim 6, characterized in that: The specific method for obtaining the abnormal degree value of the change is: The charging and discharging efficiency of all time nodes within the detection period is obtained, and the abnormal degree value of the change is calculated by the variance calculation formula.

10. An optimization control system for microgrid energy storage, characterized in that: include Data acquisition module: collects microgrid operation data in real time through sensors and monitoring equipment installed in the microgrid, where the microgrid operation data includes energy storage status data; Identification module: Identify the state of the energy storage system based on the collected energy storage state data; Output module: According to the judgment result, based on the charging and discharging efficiency data of the energy storage system during operation, obtain the variation value BYZ of the energy storage system, analyze the variation value, and generate a control signal; Processing module: Based on the control signal, the collection cycle is set, and the inclination value at the current moment and the inclination value at the starting moment are determined according to the charge and discharge efficiency curve. Then, the variation value of the energy storage system is obtained based on the inclination value at the current moment and the inclination value at the starting moment, and the variation value is compared with the variation threshold of the current energy storage system to obtain a shutdown signal or a control signal; Determination module: based on the control signal, obtain the abnormal degree value of charge and discharge efficiency and the abnormal degree value of change, analyze and obtain the node value based on the abnormal degree value of charge and discharge efficiency and the abnormal degree value of change, and determine the control time of the energy storage system according to the node value; Control module: Based on the control time point of the energy storage system, the charging and discharging modules of the energy storage system are controlled to bring the charging and discharging efficiency into a safe area.

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