A method for configuring a mobile modular energy storage system for seasonal loads

Abstract

The present invention relates to a method for configuring a movable modular energy storage switching for seasonal loads. In view of the construction needs of modern new power systems, the modular energy storage equipment is reasonably switched according to factors such as the state of charge of the energy storage battery, the voltage amplitude at the distribution network end, and the duration of the abnormal state, so that the energy storage equipment can be flexibly expanded to meet the increasing "quality" and "quantity" requirements of electricity consumption. At the same time, the modular solution helps to empower digitally, form an observable information flow, is easy to control and manage, and promotes the intelligent development of the power grid. The flexible switching of energy storage at the source end can stagger the peak and valley of the modular energy storage equipment in the distribution network, improve the power supply capacity at the end of the distribution network, and at the same time fully and efficiently utilize the capacity of the energy storage equipment, with good economy. This method is practical and feasible, has strong engineering application value, and can produce good economic benefits.

Description

Technical Field

[0001] The present invention relates to a movable modular energy storage switching configuration method for seasonal loads, which is applied in the technical field of distributed energy storage capacity allocation in a power distribution network. Background Art

[0002] Distributed energy storage is widely known for its broad application value in a variety of scenarios, including emergency power supply, renewable energy integration, equivalent capacity expansion of distribution networks, and power quality improvement. It holds enormous potential for improving both the quality of distribution network power supply and the quality of electricity consumed by consumers. Furthermore, the rapid growth of renewable energy capacity, the rapid decline in energy storage technology costs, and the rapid increase in the production and supply capacity of energy storage systems are providing strong support for the implementation of grid-level energy storage solutions, ensuring that energy storage plays an increasingly important role in addressing power system capacity shortages, improving clean energy utilization efficiency, and addressing transmission and distribution capacity expansion and upgrades.

[0003] However, due to factors such as the spatial dispersion of distributed energy storage systems, their potentially large number, and the significant variability of their functional capacity requirements depending on the target scenario, applications often require rapid, temporary networking, flexible capacity expansion, and even on-demand functional configuration. These challenges pose significant challenges to the large-scale application of distributed energy storage. Therefore, for distribution networks, balancing the multiple requirements of economy, maintainability, safety, and flexibility remains a pressing technical challenge.

[0004] An invention patent with the publication (announcement) number CN105356842B discloses a modular device combining a photovoltaic cell and an energy storage device. Specifically, it discloses combining a photovoltaic cell assembly (i.e., photovoltaic cell unit 1) and an energy storage element (i.e., energy storage unit 3) to form a modular device, and then connecting multiple modular devices in series to achieve power generation and energy storage operations. When a photovoltaic cell assembly or an energy storage element is in an abnormal operating state (including a fault state), the photovoltaic cell assembly or energy storage element will only affect the control scheme and operating state of the modular device in which it is located, and will not affect the control and operation of other modular devices, thereby improving the safety and reliability of the overall operation. However, it does not solve technical problems such as how to achieve flexible capacity expansion according to seasonal loads and how to configure functions on demand. Summary of the Invention

[0005] To address the above-mentioned technical problems, the present invention provides a method for configuring a mobile modular energy storage system for seasonal loads. This method addresses the peak power demand caused by the large-scale input of seasonal loads into the distribution network. The method considers three key factors: the state of charge of the energy storage batteries in the energy storage and distribution system, the voltage at the distribution network terminal, and the duration of two abnormal operations. This determines whether to increase or decrease the capacity configuration of the modular energy storage device. The duration of abnormal operation that the energy storage system can tolerate is determined by the total input duration of the seasonal loads, the proportion of the total seasonal loads in the energy storage system's capacity, and the severity of the abnormal operation of the energy storage system.

[0006] The technical solutions of the present invention are as follows:

[0007] A method for configuring a movable modular energy storage switching for seasonal loads includes the following steps:

[0008] Step 1: Detect the state of charge (SOC) of the energy storage battery;

[0009] Step 2: Determine the rated amplitude of the distribution network voltage U ref , and detect the voltage amplitude U of the distribution network in real time;

[0010] Step 3: Check the seasonal load input. If there is no seasonal load input, go back to step 1. If there is seasonal load input, go to the following steps;

[0011] Step 4: If the state of charge of the energy storage battery and the voltage amplitude of the distribution network simultaneously enter the preset abnormal operating range, start recording the duration t of the abnormal operating conditions of the two states;

[0012] Step 5: Determine the total seasonal load existence time as x hours;

[0013] Step 6: Check the original rated capacity P of the energy storage system E , and the increased seasonal total load power value P S ;

[0014] Step 7: Based on the original rated capacity P of the energy storage system E And the increased seasonal total load power value P S The ratio of the increased seasonal total load to the original rated capacity of the energy storage system is calculated as the load factor m;

[0015] Step 8: Based on the energy storage battery state of charge (SOC) obtained in steps 1 and 2, the voltage amplitude U at the distribution network end, the duration t of the two abnormal working states, the duration x of the total seasonal load, and the load factor m obtained in step 5, the switching status of the modular energy storage device is further determined;

[0016] Step 9: Apply the method for adjusting the modular energy storage capacity configuration according to seasonal load described above to the distribution network. According to the input situation of seasonal load, the capacity configuration of modular energy storage can be increased or decreased in real time to realize the value of distributed energy storage in aspects such as emergency power supply, new energy consumption, and distribution equivalent capacity expansion.

[0017] The specific allocation method is as follows:

[0018] 1) When 0.3 < SOC < 0.8 and 0.95U ref < U < 1.1U ref Do not increase or decrease the capacity configuration of the modular energy storage device.

[0019] 2) When 0.1 < SOC < 0.3 and 0.9U ref < U < 0.95U ref If the duration t > 3*m / x*1000, increase the capacity configuration of the modular energy storage device.

[0020] 3) When 0.1 < SOC < 0.3 and U < 0.9U ref If the duration t > 2*m / x*1000, increase the capacity configuration of the modular energy storage device.

[0021] 4) When SOC < 0.1 and 0.9U ref < U < 0.95U ref If the duration t > 2*m / x*1000, increase the capacity configuration of the modular energy storage device.

[0022] 5) When SOC < 0.1 and U < 0.9U ref If the duration t > m / x*1000, increase the capacity configuration of the modular energy storage device.

[0023] 6) When SOC > 0.8 and U > 1.1U ref If the duration t > 3h, decrease the capacity configuration of the modular energy storage device.

[0024] The present invention has the following beneficial effects:

[0025] 1. The present invention proposes a detailed segmented modular energy storage capacity configuration method for problems of distributed energy storage in aspects such as emergency power supply, new energy consumption, distribution equivalent capacity expansion, and improving the power supply quality of the distribution network. The energy storage system can flexibly increase or decrease the capacity of the energy storage system in real time according to the input situation of seasonal load and the current working state of the energy storage battery, realizing the flexible matching and on-site configuration of the energy storage device from capacity to function, delaying the investment in the transmission and distribution system, and solving the peak power demand during the input of seasonal load, thereby improving the power supply stability and reliability of the energy storage system.

[0026] 2. The present invention further considers three key factors: the state of charge of the energy storage battery in the energy storage and distribution system, the voltage at the distribution network end, and the duration of two abnormal operations to determine whether to increase or decrease the capacity configuration of the modular energy storage device. The abnormal operation time that the energy storage system can tolerate is determined by the input time of the total seasonal load, the capacity ratio of the total seasonal load in the energy storage system, and the severity of the abnormal operation of the energy storage system. By comprehensively considering various influencing factors in the energy storage power supply system, the input and removal plan of the modular energy storage device is rationally planned in sections, which improves the utilization efficiency of the energy storage energy and plays an important role in responding to the process of capacity expansion and upgrading of power transmission and distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the system operation of the present invention;

[0028] Figure 2 It is a system workflow diagram of the present invention;

[0029] Figure 3 This is a diagram showing the modular energy storage capacity configuration results of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Before introducing the specific implementation steps, the variables used are explained as follows:

[0032] (1) SOC: state of charge of energy storage battery;

[0033] (2)U ref : Rated amplitude of distribution network terminal voltage;

[0034] (3) U: voltage amplitude at the distribution network end;

[0035] (4) t: The duration during which the state of charge of the energy storage battery and the voltage amplitude at the distribution network end simultaneously enter the specified abnormal operating mode;

[0036] (5)x: duration of total seasonal load;

[0037] (6)P E : Original rated capacity of the energy storage system;

[0038] (7)P S : The added seasonal total load power value;

[0039] (8)m; the ratio of the increased seasonal total load power value to the original rated capacity of the energy storage system is called the load factor.

[0040] See also Figures 1 to 3 The specific implementation steps of the movable modular energy storage switching configuration method for seasonal loads are as follows:

[0041] This method considers three key factors: the state of charge of the energy storage battery in the energy storage and distribution system, the voltage at the distribution network end, and the duration of two abnormal operations to determine whether to increase or decrease the capacity configuration of the modular energy storage equipment. The abnormal operation time that the energy storage system can tolerate is determined by the time the total seasonal load is put into operation, the capacity proportion of the total seasonal load in the energy storage system, and the severity of the abnormal operation of the energy storage system. Flexible matching and on-site configuration of energy storage equipment from capacity to function is achieved to delay investment in the transmission and distribution system and solve the peak power demand when seasonal loads are put into operation, thereby improving the power supply stability of the energy storage system. A method process for adjusting the modular energy storage capacity configuration according to seasonal loads is described as follows.

[0042] Step 1: If Figure 1 As shown, the state of charge (SOC) of the energy storage battery is detected;

[0043] Step 2: If Figure 1 As shown, the rated amplitude of the distribution network voltage U is determined by the upper dispatching center. ref And detect the terminal voltage amplitude U of the distribution network in real time;

[0044] Step 3: If Figure 1 As shown, the upper dispatch center detects the input of seasonal loads. If there is seasonal load input, the following steps are performed, otherwise, the process returns to step 1.

[0045] Step 4: If Figure 1 As shown, the detection results of the superior dispatching center are used to determine whether the charge state of the energy storage battery and the voltage amplitude of the distribution network have simultaneously entered the preset abnormal working range. If so, the duration t of the abnormal working of the two states is recorded;

[0046] Step 5: Figure 1 As shown, the existence time of the total seasonal load is determined by the superior dispatching center to be x hours;

[0047] Step 6: Figure 1 As shown, the original rated capacity P of the energy storage system is detected by the superior dispatching center. E , and the increased seasonal total load power value P S ;

[0048] Step 7: Figure 1 As shown, the ratio m of the increased seasonal total load to the original rated capacity of the energy storage system is calculated using the following formula:

[0049] m = P S / P E

[0050] Step 8: As shown Figure 2 in the figure, based on the obtained state of charge of the energy storage battery, the amplitude of the distribution network terminal voltage U, the duration t of the two abnormal operating states, the existence time x of the total seasonal load, and the load factor m, further determine the switching situation of the modular energy storage device through the following specific allocation method;

[0051] 1) When 0.3 < SOC < 0.8 and 0.95U ref < U < 1.1U ref no configuration for increasing or decreasing the capacity of the modular energy storage device is carried out;

[0052] 2) When 0.1 < SOC < 0.3 and 0.9U ref < U < 0.95U ref if the duration t > 3*m / x*1000, configure to increase the capacity of the modular energy storage device;

[0053] 3) When 0.1 < SOC < 0.3 and U < 0.9U ref if the duration t > 2*m / x*1000, configure to increase the capacity of the modular energy storage device;

[0054] 4) When SOC < 0.1 and 0.9U ref < U < 0.95U ref if the duration t > 2*m / x*1000, configure to increase the capacity of the modular energy storage device;

[0055] 5) When SOC < 0.1 and U < 0.9U ref if the duration t > m / x*1000, configure to increase the capacity of the modular energy storage device;

[0056] 6) When SOC > 0.8 and U > 1.1U ref if the duration t > 3h, configure to reduce the capacity of the modular energy storage device;

[0057] Step 9: Apply the method for adjusting the modular energy storage capacity configuration according to the seasonal load as described above to the distribution network, and increase or decrease the capacity configuration of the modular energy storage in real time according to the input situation of the seasonal load.

[0058] Figure 3It is a result diagram of adopting the above method for adjusting the modular energy storage capacity configuration according to seasonal load. At this time, it is assumed that the existence time of the total seasonal load is 1000h, and the proportion m of the increased seasonal total load relative to the original rated capacity of the energy storage system is 50%. According to the result diagram of the capacity configuration, it can be seen that when 0.3 < SOC < 0.8 and 0.95U ref <U < 1.1U ref there is no increase or decrease in the capacity configuration of the modular energy storage device. When 0.1 < SOC < 0.3 and 0.9U ref <U < 0.95U ref if the duration t > 6h, the capacity configuration of the modular energy storage device is increased. When 0.1 < SOC < 0.3 and U < 0.9U ref if the duration t > 4h, the capacity configuration of the modular energy storage device is increased. When SOC < 0.1 and 0.9U ref <U < 0.95U ref if the duration t > 4h, the capacity configuration of the modular energy storage device is increased. When SOC < 0.1 and U < 0.9U ref if the duration t > 2h, the capacity configuration of the modular energy storage device is increased. When SOC > 0.8 and U > 1.1U ref if the duration t > 3h, the capacity configuration of the modular energy storage device is decreased.

[0059] In summary, under the control method described in this invention, it is more adaptable to the construction needs of the new power system. The energy storage can be flexibly expanded and flexibly controlled to meet the increasing demand for the "quality" and "quantity" of electricity. The modular scheme helps with digital empowerment, forms an observable information flow, is easy to control and manage, and promotes the intelligent development of the power grid. The flexible switching of the energy storage at the source end can perform peak shaving and valley filling for the modular energy storage devices in the distribution network, balance the power consumption load, improve the power supply capacity at the end of the distribution network, and at the same time can fully and efficiently utilize the capacity of the energy storage device, with good economy. This method is practical and feasible, has strong engineering application value, and can generate good economic benefits.

[0060] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A method for configuring a mobile modular energy storage system for seasonal loads, characterized by: The following steps are involved: Step 1: Detect the state of charge (SOC) of the energy storage battery; Step 2: Determine the rated amplitude of the distribution network voltage U ref , and detect the voltage amplitude U of the distribution network in real time; Step 3: Check the seasonal load input. If there is no seasonal load input, go back to step S1. If there is seasonal load input, go to the following steps; Step 4: If the state of charge of the energy storage battery and the voltage amplitude of the distribution network simultaneously enter the preset abnormal operating range, start recording the duration t of the abnormal operating conditions of the two states; Step 5: Estimate the total seasonal load duration to be x hours; Step 6: Check the original rated capacity P of the energy storage system E And the increased seasonal total load power value P S ; Step 7: Based on the original rated capacity P of the energy storage system E And the increased seasonal total load power value P S The ratio of the increased seasonal total load to the original rated capacity of the energy storage system can be calculated as the load factor m, which is calculated as follows: m=P S / P E ; Step 8: Based on the energy storage battery state of charge obtained in step 1, the distribution network voltage amplitude U obtained in step 2, the duration t of the two abnormal operating conditions obtained in step 4, the total seasonal load duration x obtained in step 5, and the load factor m obtained in step 7, further determine the switching status of the modular energy storage device; Step 9: Apply the method of adjusting the modular energy storage capacity configuration according to seasonal load to the distribution network, and increase or decrease the capacity configuration of the modular energy storage in real time according to the input of seasonal load.

2. A method for configuring a movable modular energy storage switching for seasonal loads according to claim 1, characterized in that: When 0.3 < SOC < 0.8 and 0.95U ref < U < 1.1U ref , no configuration for increasing or decreasing the capacity of the modular energy storage device is performed.

3. The method for configuring a movable modular energy storage for seasonal loads according to claim 1, wherein: When 0.1 < SOC < 0.3 and 0.9U ref < U < 0.95U ref If the duration t > 3*m / x*1000, increase the configuration of the modular energy storage device capacity.

4. The method for configuring a movable modular energy storage for seasonal load switching according to claim 1, wherein: When 0.1 < SOC < 0.3 and U < 0.9U ref If the duration t > 2*m / x*1000, increase the configuration of the modular energy storage device capacity.

5. The method for configuring a movable modular energy storage switching for seasonal loads according to claim 1, wherein: When SOC<0.1 and 0.9U ref <U<0.95U ref When the duration t>2*m / x*1000, increase the configuration of modular energy storage device capacity.

6. The method for configuring a movable modular energy storage switching for seasonal loads according to claim 1, wherein: When SOC < 0.1 and U < 0.9U ref When the duration t>m / x*1000, increase the configuration of modular energy storage device capacity.

7. The method for configuring a movable modular energy storage for seasonal load switching according to claim 1, wherein: When SOC>0.8 and U>1.1U ref If the duration t>3h, reduce the configuration of the capacity of the modular energy storage device.

Images