Energy management methods, devices, computer equipment and storage media

Abstract

This invention relates to the field of energy management technology for energy storage devices, and discloses an energy management method that determines the remaining charge and discharge demand of an energy storage device in the current time period; the remaining charge and discharge demand is used to characterize whether the charge and discharge threshold is set reasonably; based on the remaining charge and discharge demand, the operating condition of the energy storage device in the current time period is determined; based on the operating condition, the charge and discharge threshold of the energy storage device is adjusted in the next time period to perform energy management of the energy storage device. The technical solution provided by one or more embodiments of this invention can determine the operating condition directly based on the remaining charge and discharge demand of the energy storage device without additional information from trains or substations, thereby managing energy by adjusting the charge and discharge threshold. This effectively avoids the problem of poor energy-saving effect caused by the energy storage device's inability to charge or discharge in a timely manner.

Description

Technical Field

[0001] This invention relates to the field of energy management technology for energy storage devices, specifically to energy management methods, devices, computer equipment, and storage media. Background Technology

[0002] With the development of regenerative braking energy technology for trains, installing ground-based energy storage devices to recover the regenerative braking energy of trains can reduce train operating energy consumption and help achieve energy conservation and emission reduction goals. However, the energy control strategy greatly affects the energy-saving and voltage-stabilizing effect of the energy storage device. Current energy control strategies mainly include those based on no-load voltage changes, fuzzy rules, and the maximum releasable braking energy. However, existing control strategies require additional information from substations or trains, necessitating the addition of sensor equipment, making engineering implementation complex. They also cannot effectively adapt to the complex and ever-changing operating conditions in reality, resulting in poor energy-saving performance. A better solution is needed. Summary of the Invention

[0003] In view of this, the present invention provides an energy management method, apparatus, computer equipment and storage medium to solve the problem that the control strategy needs to obtain additional information from substations or trains, etc., and cannot adapt to changes in operating conditions, resulting in poor energy-saving effect.

[0004] The present invention provides an energy management method, the method comprising: determining the remaining charge and discharge demand of an energy storage device in the current time period; the remaining charge and discharge demand being used to characterize whether the charge and discharge threshold is set reasonably; determining the operating condition of the energy storage device in the current time period based on the remaining charge and discharge demand; and adjusting the charge and discharge threshold of the energy storage device in the next time period based on the operating condition, thereby performing energy management on the energy storage device.

[0005] In another aspect, the present invention provides an energy management device, the device comprising: a first determining module, configured to determine the remaining charge and discharge demand of an energy storage device in the current time period; the remaining charge and discharge demand is used to characterize whether the charge and discharge threshold is set reasonably; a second determining module, configured to determine the operating condition of the energy storage device in the current time period based on the remaining charge and discharge demand; and a management module, configured to adjust the charge and discharge threshold of the energy storage device in the next time period based on the operating condition, thereby performing energy management on the energy storage device.

[0006] In another aspect, the present invention provides a computer device comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to implement the above-described energy management method.

[0007] In another aspect, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to implement the above-described energy management method.

[0008] In this process, by determining the remaining charging and discharging demand of the energy storage device, the operating conditions within the current time period are determined based on the remaining charging and discharging demand, and the remaining charging and discharging threshold of the energy storage device is adjusted according to the operating conditions. This allows for energy management of the energy storage device without the need to obtain additional information from the train or substation, thereby improving the train braking energy recovery rate and utilization rate of the energy storage device and enhancing the energy-saving and voltage stabilization effect. Attached Figure Description

[0009] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0010] Figure 1 This is a flowchart illustrating an energy management method provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of a ground-based energy storage system structure according to an embodiment of the energy management method provided by the present invention; Figure 3 This is a schematic diagram of voltage and current dual-loop control of an energy management method provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the remaining charge and discharge requirements of an energy management method provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the charging and discharging threshold adjustment process of an energy management method provided in an embodiment of the present invention; Figure 6 This is a schematic diagram illustrating the operating conditions of an energy management method provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of a traction power supply system for an energy management method provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the no-load voltage of a traction substation according to an embodiment of the energy management method provided by the present invention; Figure 9(a) shows the remaining charge and discharge requirements of a first energy storage system according to an embodiment of the energy management method provided by the present invention; Figure 9(b) is a threshold reference diagram of a first energy storage system according to an embodiment of the present invention for an energy management method; Figure 10(a) shows the remaining charge and discharge requirements of a second energy storage system according to an embodiment of the energy management method provided by the present invention; Figure 10(b) is a threshold reference diagram of a second energy storage system according to an embodiment of the present invention for an energy management method; Figure 11(a) is a graph showing the changes in system energy-saving indicators of an energy management method provided in an embodiment of the present invention; Figure 11(b) is a graph showing the changes in system voltage regulation parameters of an energy management method provided in an embodiment of the present invention; Figure 12 This is a schematic diagram of the structure of an energy management device provided in an embodiment of the present invention; Figure 13 This is a schematic diagram of another energy management device provided in an embodiment of the present invention. Detailed Implementation

[0011] Current research on energy control strategies often employs strategies based on traction grid voltage. The main working principle involves setting charging and discharging voltage thresholds, and determining the charging, discharging, and standby states of the energy storage system based on the traction grid voltage. When the traction grid voltage is higher than the charging threshold, the energy storage system is in a charging state; when the traction grid voltage is lower than the discharging threshold, the energy storage system is in a discharging state; and when the traction grid voltage is between the charging and discharging thresholds, the energy storage system is in a standby state. When applying this method, the actual effectiveness of energy storage depends on the appropriateness of the selected charging and discharging thresholds.

[0012] Therefore, many studies have proposed methods for selecting reasonable charging and discharging thresholds for different operating conditions and influencing factors. For example, for operating conditions with varying no-load voltage, Method 1 proposes identifying the no-load voltage of the substation and then adjusting the discharge threshold based on the no-load voltage, increasing the charging and discharging threshold when the no-load voltage is high. For changes in no-load voltage and train intervals, Method 2 proposes an energy management strategy based on fuzzy rule control. Method 3 calculates the maximum releasable braking energy based on train speed and dynamically adjusts the voltage threshold to minimize line voltage drop and improve energy-saving performance.

[0013] However, the above three methods have the following problems: First, the above methods require additional information from substations or trains in practical applications, and require the addition of sensor equipment, making engineering implementation quite complex. Second, most of the above methods are designed for specific situations and cannot adapt well to the complex and ever-changing working conditions in reality.

[0014] To address at least one of the aforementioned problems, various embodiments of the present invention provide an energy management method, comprising: determining the remaining charge and discharge demand of an energy storage device in a current time period; the remaining charge and discharge demand being used to characterize whether a charge and discharge threshold is set reasonably; determining the operating condition of the energy storage device in the current time period based on the remaining charge and discharge demand; and adjusting the charge and discharge threshold of the energy storage device in a next time period based on the operating condition, thereby performing energy management on the energy storage device.

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] According to an embodiment of the present invention, an energy management method is provided. Figure 1 This is a flowchart illustrating an energy management method provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the process includes the following steps: Step S101: Determine the remaining charge and discharge demand of the energy storage device in the current time period; the remaining charge and discharge demand is used to characterize whether the charge and discharge threshold is set reasonably. Step S102: Determine the operating condition of the energy storage device in the current time period based on the remaining charging and discharging demand; Step S103: Based on the operating conditions, adjust the charging and discharging thresholds of the energy storage device in the next time period to manage the energy of the energy storage device.

[0017] In one possible implementation, the energy storage device can refer to a device for storing energy generated during train operation and releasing that energy when needed for train traction or other purposes; the energy storage device can be used to store electrical electricity generated when the train is braking and release that electrical electricity when the train is in traction to provide traction force for the train.

[0018] For example, energy storage devices may include, but are not limited to, supercapacitors, flywheels, and batteries.

[0019] Furthermore, the energy storage device can be connected in series with a DC-DC converter to form a ground-based energy storage system. The energy storage system (ESS) can be installed in the substation in parallel with the DC bus. The energy storage system can be... Figure 2 As shown, Figure 2 This is a schematic diagram of a ground-based energy storage system structure for an energy management method provided in an embodiment of the present invention.

[0020] Here, a DC-DC converter can be an electronic device used to convert DC power from one voltage level to another; a DC bus can refer to the main conductor or rail in a power system used to transmit DC power, usually connected to DC equipment (such as DC transformers, DC-AC converters, etc.) to deliver DC power to where it is needed; a traction substation can refer to a facility used to convert AC power into DC power required by a train; and 750V can refer to the rated voltage of a train line.

[0021] In one possible implementation, the duration of the current time period and the next time period can be preset according to the specific operating conditions of the train; the duration of the current time period and the duration of the next time period can be equal.

[0022] For example, the duration of the current time period and the next time period may include, but is not limited to, 120 seconds, 360 seconds, etc.

[0023] In one possible implementation, the energy storage device can employ dual-loop control, stabilizing the DC traction grid voltage through the outer voltage loop and regulating the charging and discharging current of the energy storage system through the inner current loop.

[0024] For example, such as Figure 3 As shown, Figure 3 This is a schematic diagram of voltage and current dual-loop control of an energy management method provided in an embodiment of the present invention.

[0025] The outer loop is typically responsible for the overall goals or main outputs of the system, such as controlling the voltage, power, or speed of the system. In energy storage systems, the outer loop can be responsible for stabilizing the traction grid voltage or controlling the charging and discharging power of the energy storage device. The inner loop typically controls the local details or secondary outputs of the system, such as controlling fluctuations in current, speed, or voltage. In energy storage systems, the inner loop may be responsible for regulating the charging and discharging current of the energy storage device to ensure that the goals set by the outer loop are met. Dual-loop control can achieve efficient and precise control of the energy storage system.

[0026] U char It can represent the charging threshold. U dis It can represent the discharge threshold. U dc It can represent traction network voltage. PI can refer to proportional-integral (PI) loop, which is a commonly used control system structure used to achieve closed-loop control of the system. I Lchar It can indicate the charging current requirement. I Ldis It can represent the discharge current requirement. IL It can represent actual current. It can represent current demand. PWM can be an abbreviation for Pulse Width Modulation, which is a method of controlling the average power of a signal by changing the high-level time of a pulse signal.

[0027] Here, the charging threshold can refer to a voltage value set in the energy storage device to control the charging process. When the voltage of the energy storage device reaches the set charging threshold, the charging process will be triggered or stopped. The discharging threshold can also refer to another voltage value set in the energy storage device to control the discharging process. The charging current requirement can refer to the current required by the energy storage device during the charging process. The discharging current requirement can refer to the current required by the energy storage device during the discharging process. The current requirement can refer to the current required by the energy storage device, and the actual current refers to the current output by the current energy storage device.

[0028] In one possible implementation, the remaining charge and discharge needs of the energy storage device can be reflected by the portion of the traction grid voltage that exceeds or falls below the charge and discharge threshold.

[0029] Specifically, when the energy storage device can fully meet the charging and discharging requirements, that is, when the charging and discharging current of the energy storage device can completely follow the charging current requirements. I Lchar With discharge current requirements I Ldis At this time, the traction grid voltage can be stabilized near the charge / discharge threshold; in practical applications, due to the limited energy storage capacity of the energy storage device and the maximum limitation of the charge / discharge current, when the traction grid voltage... U dc Below the discharge threshold U dis At this time, the energy storage device enters the discharge state, and if the current demand of the PI loop output is... I Ldis If the discharge current exceeds the maximum discharge current of the energy storage device or the energy storage device itself is empty, then the energy storage device cannot fully meet the discharge demand, and the traction grid voltage will fall below the discharge threshold; when the traction grid voltage... U dc Above the charging threshold U char At this time, the energy storage device can enter the charging state, if the current demand of the PI loop output is... I Lchar If the charging current exceeds the maximum charging current of the energy storage device or the energy storage device itself is already fully charged, then the energy storage device cannot fully meet the charging needs, and the traction grid voltage will be higher than the charging threshold.

[0030] Here, when the energy storage device enters the discharge state, if the energy storage device cannot play the role of discharging to replenish energy, the traction grid voltage will decrease further from being stable near the discharge threshold to below the discharge threshold due to continuous discharge; when the energy storage device enters the charging state, if the energy storage device cannot play the role of charging to reduce grid energy, the traction grid voltage will increase further from being stable near the charging threshold to above the charging threshold due to excessive electricity that cannot be released.

[0031] In one possible implementation, the remaining charging and discharging demands of the energy storage device in the current time period are determined. The operating conditions are classified according to the remaining charging and discharging demands to determine the corresponding operating conditions of the energy storage device in the current time period. In the next time period, the charging and discharging thresholds of the energy storage device are adjusted. The energy storage device is then set according to the adjusted charging and discharging thresholds for energy management.

[0032] By using the above method, the remaining charging and discharging demand of the energy storage device in the current period can be determined without the need to install additional sensors or other equipment on the train or in the substation, or to obtain additional operating condition information that is difficult to measure. This reduces the difficulty of data acquisition and improves the energy-saving effect of the energy storage device.

[0033] In some embodiments, determining the remaining charge and discharge requirements of the energy storage device during the current time period includes: Determine the traction grid voltage corresponding to the energy storage device. If the traction grid voltage is greater than the charging threshold, determine the portion of the traction grid voltage that is greater than the charging threshold in the current time period as the first part. Determine the integral of the first part in the current time period as the remaining charging demand. When the traction grid voltage is less than the discharge threshold, the portion of the traction grid voltage that is less than the discharge threshold in the current time period is determined as the second part, and the integral of the second part in the current time period is determined as the remaining discharge demand.

[0034] In one possible implementation, such as Figure 4 As shown, Figure 4 This is a schematic diagram of the remaining charge and discharge demand of an energy management method provided in an embodiment of the present invention. The remaining charge demand is determined by integrating the portion of the traction grid voltage that is greater than the charging threshold in the current time period using the following formula; the remaining discharge demand is determined by integrating the portion of the traction grid voltage that is less than the discharging threshold in the current time period.

[0035]

[0036] in, It can indicate the remaining charging demand. T can represent the remaining discharge demand, and T can represent the current time period. It can represent the traction network voltage. It can represent the charging threshold. It can represent the discharge threshold.

[0037] By integrating the portion of the traction grid voltage that is greater than the charging threshold and the portion that is less than the discharging threshold over the current time period T using the above method, the remaining charging and discharging demand can be determined. This allows us to ascertain the charging and discharging status of the energy storage device within the current time period T. The charging and discharging thresholds can then be adjusted based on the remaining charging and discharging demand. This method is simple and effective, and can significantly improve the energy-saving performance of the energy storage device.

[0038] In some embodiments, determining the operating condition of the energy storage device in the current time period based on the remaining charge and discharge demand includes: Determine the magnitude of the remaining charging and discharging demands of the energy storage device in the current time period; When the remaining charging demand is greater than the preset multiple of the remaining discharging demand, the energy storage device is determined to be in the first operating condition. When the remaining discharge demand is greater than the preset multiple of the remaining charging demand, the energy storage device is determined to be in the second operating condition. When the remaining charging demand is less than or equal to a preset multiple of the remaining discharging demand, and the remaining discharging demand is less than or equal to a preset multiple of the remaining charging demand, the energy storage device is determined to be in the third operating condition.

[0039] In one possible implementation, the preset multiplier may include, but is not limited to, 1.5 times.

[0040] Specifically, the remaining charging demand and remaining discharging demand within the current time period T are determined. If the remaining charging demand is greater than 1.5 times the remaining discharging demand, it can be said that the remaining charging demand is much greater than the remaining discharging demand, and the energy storage device is determined to be in the first operating condition. If the remaining discharging demand is greater than 1.5 times the remaining charging demand, it can be said that the remaining discharging demand is much greater than the remaining charging demand, and the energy storage device is determined to be in the second operating condition. If the remaining charging demand is less than or equal to 1.5 times the remaining discharging demand, and the remaining discharging demand is less than or equal to 1.5 times the remaining charging demand, it can be said that the remaining charging demand and the remaining discharging demand are similar in magnitude, and the energy storage device is determined to be in the third operating condition.

[0041] Here, when the energy storage device is in the first operating condition, it indicates that the charging and discharging threshold is set too low in the current period, affecting the timely discharge of the energy storage device; when the energy storage device is in the second operating condition, it indicates that the charging and discharging threshold is set too high in the current period, affecting the timely charging of the energy storage device; when the energy storage device is in the third operating condition, it indicates that the charging and discharging threshold is set reasonably in the current period.

[0042] By using the above method, the operating conditions of the energy storage device are determined based on the relationship between the remaining charging demand and the remaining discharging demand. This allows for a determination of whether the charging and discharging thresholds are set reasonably within the current time period. This approach can effectively adapt to complex and ever-changing operating conditions in reality, further improving the charging and discharging performance of the energy storage device, thereby maintaining the stability of the traction network voltage and increasing the reliability of train operation.

[0043] In some embodiments, adjusting the charge and discharge thresholds of the energy storage device in the next time period according to operating conditions to perform energy management of the energy storage device includes: When the energy storage device is determined to be in the first operating condition, the charging and discharging threshold of the energy storage device is increased in the next time period; When the energy storage device is determined to be in the second operating condition, the charging and discharging threshold of the energy storage device is reduced in the next time period; When the energy storage device is determined to be in the third operating condition, the charging and discharging threshold of the energy storage device shall be maintained in the next time period.

[0044] In one possible implementation, the current time period T is determined, and it is judged whether the energy storage device is in the first, second, or third operating condition within T. The charging and discharging thresholds of the energy storage device are adjusted accordingly in the next time period T. If it is in the first operating condition, it indicates that the charging and discharging threshold of the energy storage device is set too low within T, and the charging and discharging threshold of the energy storage device is increased in the next time period T. If it is in the second operating condition, it indicates that the charging and discharging threshold of the energy storage device is set too high within T, and the charging and discharging threshold of the energy storage device is decreased in the next time period T. If it is in the third operating condition, it indicates that the charging and discharging threshold of the energy storage device is set reasonably within T, and the charging and discharging threshold of the energy storage device is maintained in the next time period T.

[0045] For example, such as Figure 5 As shown, Figure 5 This is a schematic diagram of the charging and discharging threshold adjustment process of an energy management method provided in an embodiment of the present invention. The charging and discharging threshold process is divided into time periods according to the current time period T. The operating condition of the energy storage device in the current time period T is determined, and the threshold is adjusted in the next time period T. After the threshold is adjusted, the operating condition is determined again, and the threshold adjustment is continued in the next time period T.

[0046] Here, threshold adjustment can include: threshold increase, threshold decrease, and threshold hold.

[0047] By using the above method, the charging and discharging threshold is determined in the current time period, and the threshold is directly adjusted in the next time period. This ensures that the threshold remains stable and is neither too large nor too small, allowing the energy storage device to charge and discharge stably, improving the efficiency of energy absorption and release, and increasing energy-saving effects.

[0048] In some embodiments, when it is determined that the energy storage device is in a first operating condition, increasing the charge / discharge threshold of the energy storage device in the next time period includes: When the energy storage device is determined to be in the first operating condition, the charging and discharging threshold is increased by increasing the reference value of the charging and discharging threshold. The improved charge / discharge threshold is expressed by the following expression:

[0049] in, This indicates the increased charging threshold. This indicates the increased discharge threshold. This represents the base value after the increase. Represents a non-negative integer; The increased baseline value is represented by the following expression:

[0050] in, The increased baseline value, To increase the quantity, >0.

[0051] Specifically, when the energy storage device is determined to be in the first operating condition, the charge and discharge threshold setting of the energy storage device is deemed too low, as shown in the expression, for the charge and discharge threshold reference value. Increase The charge / discharge threshold is increased.

[0052] By using the above methods and increasing the charge and discharge threshold, on the one hand, the charge and discharge process of the energy storage device can be made more stable, thus stabilizing the traction grid voltage; on the other hand, the charge and discharge capacity of the energy storage device can be increased, which helps to release and utilize the stored energy.

[0053] In some embodiments, when it is determined that the energy storage device is in a second operating condition, reducing the charge / discharge threshold of the energy storage device in the next time period includes: When the energy storage device is determined to be in the second operating condition, the charging and discharging thresholds are reduced by lowering the reference value of the charging and discharging thresholds. The reduced charge / discharge threshold is expressed by the following expression:

[0054] in, This indicates the reduced charging threshold. This indicates the reduced discharge threshold. This represents the reduced baseline value. Represents a non-negative integer; The reduced benchmark value is represented by the following expression:

[0055] in, The reduced benchmark value, To reduce the amount, >0.

[0056] Specifically, when the energy storage device is determined to be in the second operating condition, the charge / discharge threshold setting of the energy storage device is deemed too high, as shown in the expression, regarding the reference value of the charge / discharge threshold. reduce The charge / discharge threshold is lowered.

[0057] By using the above methods, lowering the charge and discharge threshold can increase the energy storage charging capacity, increase the recovery of regenerative braking energy of the train, and improve the capacity utilization of energy storage.

[0058] In some embodiments, taking data from a specific domestic railway line as an example, considering the differences in no-load voltage and departure intervals at various traction substations, a comparison is made between the embodiments of the present invention and the fixed threshold strategy before threshold adjustment. The energy consumption of the substation, braking resistor energy consumption, energy saving rate, and voltage stabilization rate are compared.

[0059] Here, the energy saving rate is calculated using the following formula:

[0060] in, E NOSC Sub can refer to the output of the traction substation when no energy storage device is connected. E sc sub can refer to the output of the traction substation after the energy storage device is connected.

[0061] The voltage regulation ratio is calculated using the following formula:

[0062] in, unoess pk It can refer to the train current collector voltage when no energy storage device is connected, and uess pk can refer to the train current collector voltage when an energy storage device is connected, Δ T can refer to the time period when the voltage of the train's current collector is higher than 900V, Δ l T can refer to the time period when the voltage of the train's current collector is below 750V. N t It can refer to the total number of trains within a section of the line.

[0063] Furthermore, 900V can refer to the starting voltage of the train's braking resistor, and 750V can refer to the rated voltage for train operation.

[0064] To verify the effectiveness of the embodiments of the present invention, typical operating conditions for the entire day were extracted based on the operating characteristics of a certain actual line on weekdays, such as... Figure 6 As shown, Figure 6This is a schematic diagram of the operating conditions of a method provided in an embodiment of the present invention; the daily operating period is from 6:00 to 23:00, a total of 17 hours, with 6-minute cycles, including a total of 170 cycles; the periods from 6:00 to 10:00 and from 16:30 to 20:00 are the morning peak and evening peak, respectively, with a smaller departure interval of 120 seconds; the periods from 10:00 to 16:30 and from 20:00 to 23:00 are off-peak periods, with a larger departure interval of 360 seconds.

[0065] A simulation verification was conducted on the traction power supply system consisting of five traction substations and two energy storage devices along an actual route. Figure 7 As shown, Figure 7 This is a schematic diagram of a traction power supply system for an energy processing method provided in an embodiment of the present invention. To simulate the impact of no-load voltage fluctuations, the no-load voltages of the five substations are as follows: Figure 8 As shown, Figure 8 This is a schematic diagram of the no-load voltage of a traction substation according to an embodiment of the present invention. The no-load voltage of each traction substation increases by 20V from 6:00 to 16:30 during the period from 16:30 to 23:00.

[0066] according to Figure 6 Typical operating conditions were simulated, both with and without energy storage devices. With energy storage devices, the method of this embodiment was used, wherein parameter 'a' in the charge / discharge threshold adjustment formula was selected as 10V, and the threshold reference adjustment amount Δ... U 0 is set to 5V; the initial threshold values ​​of both energy storage devices are set to 830V, and the threshold adjustment period T is 360s; the changes in the remaining charge and discharge demand and threshold reference for each time period of ESS1 and ESS2 are shown in Figures 9 and 10, respectively; wherein, Figure 9(a) is the remaining charge and discharge demand of the first energy storage system of an energy management method provided in an embodiment of the present invention, Figure 9(b) is the threshold reference diagram of the first energy storage system of an energy management method provided in an embodiment of the present invention, Figure 10(a) is the remaining charge and discharge demand of the second energy storage system of an energy management method provided in an embodiment of the present invention, and Figure 10(b) is the threshold reference diagram of the second energy storage system of an energy management method provided in an embodiment of the present invention; when the remaining charge demand is much greater than the remaining discharge demand, the energy storage threshold reference increases adaptively; when the remaining discharge demand is much greater than the remaining charge demand, the energy storage threshold reference decreases adaptively until the deviation of the remaining charge and discharge demand is small; when the no-load voltage and departure interval change, the balance point of the remaining charge and discharge demand will also change.

[0067] For example, with a first energy storage system (such as...) Figure 7Taking ESS1 as an example, during the 0-40 6-minute periods, the train departure interval is 120 seconds, and the threshold benchmark corresponding to the balance point of remaining charging and discharging demand is 825V. During the 40-105 6-minute periods, the train departure interval becomes 360 seconds. Since the remaining charging demand is much greater than the remaining discharging demand under the previous threshold benchmark, the threshold benchmark is adaptively adjusted to 850V. During the 105-140 6-minute periods, the train departure interval becomes 120 seconds again, but the no-load voltage increases by 20V, and the threshold benchmark becomes 840V. During the 140-170 6-minute periods, the train departure interval becomes 360 seconds. Compared to the 40-105 6-minute periods, the no-load voltage increases by 20V, so the threshold benchmark becomes 860V. It can be seen that the threshold benchmark can adapt to changes in departure interval and no-load voltage, resulting in a smaller deviation in the final remaining charging and discharging demand.

[0068] Figure 11 shows the total energy saving rate and voltage stabilization rate of the five traction substations. Figure 11(a) is a graph showing the change of system energy saving index of an energy management method provided in an embodiment of the present invention, and Figure 11(b) is a graph showing the change of system voltage stabilization index of an energy management method provided in an embodiment of the present invention. It can be seen that as the threshold is adaptively adjusted, both the energy saving rate and the voltage stabilization rate will increase to a higher value. Affected by the charging and discharging efficiency of the energy storage device, the energy saving rate increases significantly and then decreases slightly during the threshold benchmark adjustment process, but it will still remain at a high level. In the 41st time period, the voltage stabilization rate increases significantly and then decreases. The reason is that the departure interval suddenly changes, which leads to a change in the train operating conditions. During this time period, the total braking energy of the train is relatively small. After the 42nd time period, the train operating conditions begin to cycle in 360s cycles. Overall, when the departure interval and no-load voltage change, the embodiment of the present invention can effectively improve the energy storage energy saving and voltage stabilization effect.

[0069] Figure 12 This is a schematic diagram of the structure of an energy processing method provided in an embodiment of the present invention, as shown below. Figure 12 As shown, the device can be applied to intelligent electronic devices such as servers and computers; the device includes: a first determining module 1201, a second determining module 1202, and a management module 1203; The first determining module 1201 is used to determine the remaining charge and discharge demand of the energy storage device in the current time period; the remaining charge and discharge demand is used to characterize whether the charge and discharge threshold is set reasonably. The second determining module 1202 is used to determine the operating condition of the energy storage device in the current time period based on the remaining charging and discharging demand; The management module 1203 is used to adjust the charging and discharging threshold of the energy storage device in the next time period according to the operating conditions, and to process the energy of the energy storage device.

[0070] Specifically, the first determining module 1201 is used to determine the traction grid voltage corresponding to the energy storage device. When the traction grid voltage is greater than the charging threshold, the part of the traction grid voltage that is greater than the charging threshold in the current period is determined as the first part, and the integral of the first part in the current period is determined as the remaining charging demand. If the traction grid voltage is less than the discharge threshold, the portion of the traction grid voltage that is less than the discharge threshold in the previous period is determined as the second part, and the integral of the second part in the previous period is determined as the remaining discharge demand.

[0071] Specifically, the second determining module 1202 is used to determine the magnitude of the remaining charging demand and the remaining discharging demand of the energy storage device in the current time period; When the remaining charging demand is greater than the preset multiple of the remaining discharging demand, the energy storage device is determined to be in the first operating condition. When the remaining discharge demand is greater than the preset multiple of the remaining charging demand, the energy storage device is determined to be in the second operating condition. When the remaining charging demand is less than or equal to a preset multiple of the remaining discharging demand, and the remaining discharging demand is less than or equal to a preset multiple of the remaining charging demand, the energy storage device is determined to be in the third operating condition.

[0072] Specifically, the management module 1203 is used to determine that when the energy storage device is in the first operating condition, to increase the charging and discharging threshold of the energy storage device in the next time period; When the energy storage device is determined to be in the second operating condition, the charging and discharging threshold of the energy storage device is reduced in the next time period; When the energy storage device is determined to be in the third operating condition, the charging and discharging threshold of the energy storage device shall be maintained in the next time period.

[0073] Specifically, the management module 1203 is used to determine that when the energy storage device is in the first operating condition, it increases the charging and discharging threshold by increasing the reference value of the charging and discharging threshold. The improved charge / discharge threshold is expressed by the following expression:

[0074] in, This indicates the increased charging threshold. This indicates the increased discharge threshold. This represents the base value after the increase. Represents a non-negative integer; The increased baseline value is represented by the following expression:

[0075]

[0076] in, The increased baseline value, To increase the quantity, >0.

[0077] Specifically, the management module 1203 is used to determine that when the energy storage device is in the second operating condition, it reduces the charging and discharging threshold by lowering the reference value of the charging and discharging threshold. The reduced charge / discharge threshold is expressed by the following expression:

[0078] in, This indicates the reduced charging threshold. This indicates the reduced discharge threshold. This represents the reduced baseline value. Represents a non-negative integer; The reduced benchmark value is represented by the following expression:

[0079] in, The reduced benchmark value, To reduce the amount, >0.

[0080] It should be noted that the energy processing device provided in the above embodiments is only illustrated by the division of the above-described program modules when implementing the corresponding energy processing method. In practical applications, the above processing can be assigned to different program modules as needed, that is, the internal structure of the device can be divided into different program modules to complete all or part of the processing described above. Furthermore, the device provided in the above embodiments and the corresponding... Figure 1 The embodiments of the methods shown belong to the same concept, and their specific implementation process can be found in the method embodiments, which will not be repeated here.

[0081] To implement the method of the embodiments of the present invention, the embodiments of the present invention provide an energy processing device, such as... Figure 13 As shown, the device includes: a processor 1301 and a memory 1302 for storing computer programs capable of running on the processor; wherein, When the processor 1301 runs the computer program, it performs the following actions: determining the remaining charge / discharge demand of the energy storage device in the current time period; the remaining charge / discharge demand is used to characterize whether the charge / discharge threshold is set reasonably; determining the operating condition of the energy storage device in the current time period based on the remaining charge / discharge demand; and adjusting the charge / discharge threshold of the energy storage device in the next time period based on the operating condition, thereby processing the energy of the energy storage device. Specifically, the device can perform the following actions: Figure 1 The method shown is the same as Figure 1 The energy processing method embodiments shown belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be repeated here.

[0082] In practical applications, such as Figure 13 As shown, the device may further include at least one network interface 1303. The various components in the energy processing device are coupled together via a bus system 1304. It is understood that the bus system 1304 is used to enable communication between these components. In addition to a data bus, the bus system 1304 also includes a power bus, a control bus, and a status signal bus. However, for clarity, in… Figure 13 All buses are designated as bus system 1304. The number of processors 1301 can be at least one. Network interface 1303 is used for wired or wireless communication between the energy processing device and other devices.

[0083] The memory 1302 in this embodiment of the invention is used to store various types of data to support the operation of the energy processing device.

[0084] The methods disclosed in the above embodiments of the present invention can be applied to processor 1301, or implemented by processor 1301. Processor 1301 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in processor 1301 or by instructions in the form of software. The processor 1301 may be a general-purpose processor, a digital signal processor (DSP), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Processor 1301 can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the methods disclosed in the embodiments of the present invention can be directly manifested as being executed by a hardware decoding processor, or being executed by a combination of hardware and software modules in the decoding processor. The software modules may be located in a storage medium, which is located in memory 1302. Processor 1301 reads the information in memory 1302 and completes the steps of the aforementioned method in conjunction with its hardware.

[0085] In an exemplary embodiment, the energy processing device may be implemented by one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers (MCUs), microprocessors, or other electronic components to perform the aforementioned method.

[0086] This invention also provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it performs the following: determining the remaining charge / discharge demand of an energy storage device in the current time period; the remaining charge / discharge demand is used to characterize whether the charge / discharge threshold is set reasonably; determining the operating condition of the energy storage device in the current time period based on the remaining charge / discharge demand; and adjusting the charge / discharge threshold of the energy storage device in the next time period based on the operating condition, thereby performing energy processing on the energy storage device. Specifically, the computer program can also perform the following: Figure 1 The method shown is the same as Figure 1 The method embodiments shown belong to the same concept, and their specific implementation process can be found in the method embodiments, which will not be repeated here.

[0087] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0088] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected to achieve the purpose of this embodiment according to actual needs.

[0089] In addition, in the various embodiments of the present invention, each functional unit can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0090] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0091] Alternatively, if the integrated units of this invention are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this invention, or the parts that contribute to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROM, RAM, magnetic disks, or optical disks.

[0092] It should be noted that terms such as "first" and "second" are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0093] Furthermore, the technical solutions described in the embodiments of this application can be combined arbitrarily without conflict.

[0094] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An energy management method applied to a ground-based energy storage system, the ground-based energy storage system comprising energy storage devices and a DC-DC converter connected in series and installed in a traction substation in parallel with a DC bus; the energy storage devices are used to store energy generated when the train is in braking state and to release the energy when the train is in traction state to provide traction force for the train, characterized in that, The method includes: A charging threshold for controlling the charging process of the energy storage device and a discharge threshold for controlling the discharging process of the energy storage device are set for the energy storage device. The traction grid voltage corresponding to the energy storage device is determined, and the operating state of the energy storage device is determined based on the traction grid voltage, the charging threshold, and the discharging threshold; wherein, if the traction grid voltage is higher than the charging threshold, the energy storage device is determined to be in a charging state; if the traction grid voltage is lower than the discharging threshold, the energy storage device is determined to be in a discharging state; if the traction grid voltage is between the charging threshold and the discharging threshold, the energy storage device is determined to be in a standby state. The remaining charge and discharge demand of the energy storage device in the current time period is determined based on the traction network voltage; the remaining charge and discharge demand includes the remaining charging demand and the remaining discharging demand; the remaining charging demand is the integral of the portion of the traction network voltage that is greater than the charging threshold in the current time period; the remaining discharging demand is the integral of the portion of the traction network voltage that is less than the discharging threshold in the current time period; the remaining charge and discharge demand is used to characterize whether the charging threshold and the discharging threshold are set reasonably; Based on the remaining charging and discharging requirements, determine the operating condition of the energy storage device during the current time period; Based on the operating conditions, the charging threshold and the discharging threshold of the energy storage device are adjusted in the next time period to perform energy management on the energy storage device.

2. The method according to claim 1, characterized in that, Determining the operating condition of the energy storage device during the current time period based on the remaining charging and discharging demand includes: Determine the magnitude of the remaining charging and discharging demands of the energy storage device in the current time period; When the remaining charging demand is greater than the remaining discharging demand by a preset multiple, the energy storage device is determined to be in a first operating condition. When the remaining discharge demand is greater than the remaining charging demand by a preset multiple, the energy storage device is determined to be in the second operating condition. When the remaining charging demand is less than or equal to a preset multiple of the remaining discharging demand, and the remaining discharging demand is less than or equal to a preset multiple of the remaining charging demand, the energy storage device is determined to be in the third operating condition.

3. The method according to claim 2, characterized in that, The step of adjusting the charging threshold and discharging threshold of the energy storage device in the next time period according to the operating conditions, and performing energy management on the energy storage device, includes: When the energy storage device is determined to be in the first operating condition, the charging threshold and the discharging threshold of the energy storage device are increased in the next time period; When it is determined that the energy storage device is in the second operating condition, the charging threshold and the discharging threshold of the energy storage device are reduced during the next time period. When the energy storage device is determined to be in the third operating condition, the charging threshold and the discharging threshold of the energy storage device are maintained during the next time period.

4. The method according to claim 3, characterized in that, When the energy storage device is determined to be in a first operating condition, increasing the charging threshold and the discharging threshold of the energy storage device in the next time period includes: When the energy storage device is determined to be in the first operating condition, the charging threshold and the discharging threshold are increased by increasing the reference values ​​of the charging threshold and the discharging threshold. The improved charging threshold and discharging threshold are represented by the following expressions: in, This indicates the increased charging threshold. This indicates the increased discharge threshold. This represents the increased baseline value. Represents a non-negative integer; The increased baseline value is represented by the following expression: in, The increased baseline value, This represents the baseline value before the increase. To increase the quantity, >

0.

5. The method according to claim 3, characterized in that, When it is determined that the energy storage device is in the second operating condition, reducing the charging threshold and the discharging threshold of the energy storage device in the next time period includes: When the energy storage device is determined to be in the second operating condition, the charging threshold and the discharging threshold are reduced by lowering the reference values ​​of the charging threshold and the discharging threshold. The reduced charging threshold and the discharging threshold are represented by the following expressions: in, This indicates the reduced charging threshold. This indicates the reduced discharge threshold. This represents the reduced baseline value. Represents a non-negative integer; The reduced benchmark value is represented by the following expression: in, The reduced benchmark value, This represents the baseline value before the reduction. To reduce the amount, >

0.

6. An energy management device applied to a ground-based energy storage system, the ground-based energy storage system comprising energy storage devices and a DC-DC converter connected in series and installed in a traction substation in parallel with a DC bus; the energy storage devices are used to store energy generated when the train is in a braking state and to release the energy when the train is in a traction state to provide traction force for the train, characterized in that, The device includes: A first determining module is configured to determine the traction grid voltage corresponding to the energy storage device, and determine the operating state of the energy storage device based on the traction grid voltage, a charging threshold, and a discharging threshold. Specifically, if the traction grid voltage is higher than the charging threshold, the energy storage device is determined to be in a charging state; if the traction grid voltage is lower than the discharging threshold, the energy storage device is determined to be in a discharging state; if the traction grid voltage is between the charging threshold and the discharging threshold, the energy storage device is determined to be in a standby state. Furthermore, the module determines the remaining charging and discharging demand of the energy storage device in the current time period based on the traction grid voltage. The remaining charging and discharging demand includes remaining charging demand and remaining discharging demand. The remaining charging demand is the integral of the portion of the traction grid voltage greater than the charging threshold in the current time period; the remaining discharging demand is the integral of the portion of the traction grid voltage less than the discharging threshold in the current time period. The remaining charging and discharging demand is used to characterize whether the charging threshold and the discharging threshold are set reasonably. The second determining module is used to determine the operating condition of the energy storage device in the current time period based on the remaining charging and discharging demand; The management module is used to set a charging threshold for controlling the charging process of the energy storage device and a discharging threshold for controlling the discharging process of the energy storage device; it is also used to adjust the charging threshold and the discharging threshold of the energy storage device in the next time period according to the operating conditions, so as to perform energy management on the energy storage device.

7. A computer device, characterized in that, include: A memory and a processor are communicatively connected, the memory storing computer instructions, and the processor executing the computer instructions to perform the energy management method of any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the energy management method according to any one of claims 1 to 5.

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