A stable regulation method for extending the cycle life of photovoltaic energy storage

Abstract

The present invention relates to the field of battery charging technology, and specifically to a stable regulation method for extending the cycle life of photovoltaic energy storage. The present invention determines the grid dependence based on the degree of demand for charging of the battery and the photovoltaic power generation power at each moment; obtains the power supply and demand performance based on the electric vehicle power and temperature of the electric vehicle at each moment, and determines the electric vehicle power supply performance at each moment based on the relative size of the power supply and demand performance of different types of electric vehicles at each moment; and determines the charging and energy replenishment power of each battery at each moment in combination with the grid dependence, the power supply and demand performance and the electric vehicle power supply performance. The present invention comprehensively considers the supply and demand performance of photovoltaic power generation, power grid, electric vehicle and battery to accurately adjust the charging and energy replenishment power of the power station battery, and can more flexibly cope with complex working conditions such as electric vehicle usage patterns and changes in photovoltaic power generation, effectively reduce the deep charge and deep discharge phenomenon of the battery, and extend the battery life.

Description

Technical Field

[0001] The present invention relates to the technical field of battery charging, and in particular to a stable regulation method for extending the cycle life of photovoltaic energy storage. Background Art

[0002] The integrated photovoltaic, storage and charging and discharging power station is a power station system for tram services, which is composed of a power grid supply and distribution system, an energy storage system, a photovoltaic power generation system, and a vehicle charging and discharging system. The battery of the energy storage system is an important part of the charging and discharging of the power station. It can accept charging supply from the power grid distribution, photovoltaic power generation and tram discharge, and can also charge trams and discharge supply to the grid in reverse. After long-term charging and discharging processes, the battery will frequently experience the adverse phenomenon of deep charging and deep discharging, thereby reducing the battery cycle life.

[0003] Existing methods manage battery charging and discharging behavior through power thresholds. That is, when the real-time power level of the battery meets a specific power threshold, the battery's charging status to the grid is adjusted, such as limiting the charging current or suspending charging, to reduce the deep charging and deep discharging phenomenon of the battery. However, in actual scenarios, the fluctuation of photovoltaic power generation in the power station and the usage pattern of the tram, that is, the random charging and power supply, will cause the real-time power level of the battery to frequently switch near the threshold. As a result, it is difficult to effectively manage the battery charging and discharging behavior under complex power station operating conditions by adjusting the battery charging power through the real-time power level of the battery. This may cause the battery to frequently experience deep charging and deep discharging, shortening the battery's service life and making the stable regulation effect of the photovoltaic energy storage cycle life poor. Summary of the Invention

[0004] In order to solve the technical problem that adjusting the battery charging power by real-time battery power is difficult to meet the complex changes in power station operating conditions and shorten the battery life, the purpose of the present invention is to provide a stable regulation method for extending the cycle life of photovoltaic energy storage. The technical solution adopted is as follows:

[0005] The present invention proposes a stable regulation method for extending the cycle life of photovoltaic energy storage, the method comprising:

[0006] Obtaining the photovoltaic power generation power of the photovoltaic storage charging and discharging integrated power station at each moment, the electric vehicle power and temperature of each electric vehicle at each moment, and the battery power of each battery at each moment; the power station includes different types of electric vehicles;

[0007] Obtaining the grid dependence of each battery at each moment based on the charging demand of each battery at each moment and the photovoltaic power generation power;

[0008] Obtaining a power supply and demand performance of each tram at each moment based on the tram power and temperature of each tram at each moment, and determining a tram power supply performance at each moment based on the relative magnitudes of the power supply and demand performances of different types of trams at each moment;

[0009] The charging power of each battery at each moment is determined according to the battery power of all batteries at each moment, the grid dependence and the power supply performance.

[0010] Furthermore, obtaining the grid dependency of each battery at each moment includes:

[0011] Get the performance deficiency of each battery at each moment;

[0012] Obtaining a charging demand for each battery at each moment based on a difference between the battery power of each battery at each moment and a preset safety power and the performance deficiency;

[0013] The grid dependence of each battery at each moment is obtained based on the photovoltaic power generation power and the charging demand at each moment; the photovoltaic power generation power and the grid dependence are negatively correlated, and the charging demand and the grid dependence are positively correlated.

[0014] Furthermore, the method for obtaining the charging demand includes:

[0015] The battery power range is divided into a front sub-range and a rear sub-range based on a preset safety power; if the battery power of each battery at each moment is within the front sub-range, the difference and the charging demand are positively correlated; if the battery power of each battery at each moment is within the rear sub-range, the difference and the charging demand are negatively correlated.

[0016] Furthermore, obtaining the power supply and demand performance of each electric vehicle at each moment includes:

[0017] The types of trams include charging trams and discharging trams;

[0018] Calculating the sum of the squares of the differences between the electric power of each charging electric vehicle at each moment and the median and minimum values ​​of the preset fast charging range, performing negative correlation and normalization on the square roots of the sums of squares, and obtaining the charging consumption performance of each charging electric vehicle at each moment;

[0019] Normalize the electric quantity of each discharging tram at each moment to obtain the discharge supply performance of each discharging tram at each moment;

[0020] The charging consumption performance and the discharging supply performance are recorded as initial supply and demand performance, and the initial supply and demand performance is adjusted using the temperature of each electric vehicle at each moment to obtain the power supply and demand performance of each electric vehicle at each moment.

[0021] Furthermore, the determining of the electric vehicle power supply performance at each moment includes:

[0022] Calculate the cumulative sum of the power supply and demand performance of all electric vehicles of each category at each moment as the overall supply and demand value of each category of electric vehicles at each moment; take the ratio of the overall supply and demand value of the discharging electric vehicles to the charging electric vehicles at each moment as the initial performance of the electric vehicles' power supply to the power station at each moment;

[0023] The initial power supply performance degree at each moment is adjusted by using the initial power supply performance degree at the adjacent moments to obtain the electric vehicle power supply performance degree at each moment.

[0024] Furthermore, determining the charging power of each battery at each moment includes:

[0025] Calculating the average battery power of all batteries at each moment; obtaining the energy replenishment requirement of each battery at each moment based on the grid dependence, the power supply performance, and the average; the grid dependence is positively correlated with the energy replenishment requirement, and the power supply performance and the average are negatively correlated with the energy replenishment requirement;

[0026] The preset energy replenishment power is weighted using the energy replenishment demand to obtain the charging energy replenishment power of each battery at each moment.

[0027] Furthermore, the method for obtaining the performance deficiency degree includes:

[0028] Get the charging power and charging rate of each battery at each moment;

[0029] Select any time as an example time and any battery as an example battery, and select a reference rate for the example battery at the example time from the charging rates of each battery except the example battery at the example time and the time before the example time; the charging power of the corresponding battery at the time corresponding to the reference rate is equal to the charging power of the example battery at the example time, and the time corresponding to the reference rate is closest to the example time;

[0030] The difference between the mean of all reference rates and the charging rate of each battery at each moment is normalized to obtain the performance deficiency of each battery at each moment.

[0031] Furthermore, the adjusting the initial power supply and demand performance by using the temperature of each electric vehicle at each moment to obtain the power supply and demand performance of each electric vehicle at each moment includes:

[0032] The ratio of the temperature of each tram at each moment to the maximum temperature of the trams of its category is calculated, and the initial supply and demand performance is weighted by the difference between a constant 1 and the ratio to obtain the power supply and demand performance of each tram at each moment.

[0033] Furthermore, the power supply performance index is data of corresponding positions on a fitted straight line obtained by performing straight-line fitting on the power supply initial performance index at each moment and its adjacent moments.

[0034] Furthermore, the battery power in the front subinterval is less than or equal to a preset safety power, and the battery power in the rear subinterval is greater than the preset safety power.

[0035] Furthermore, the preset fast charging range is 20% to 80%.

[0036] Furthermore, the preset energy replenishment power is 10 kilowatts.

[0037] The present invention has the following beneficial effects:

[0038] In the embodiment of the present invention, the photovoltaic power generation power and the battery's demand for charging reflect the amount of electrical energy that needs to be drawn from the power grid for battery charging, indicating the degree of dependence of battery charging on the power distribution of the power grid; the electric power of the tram reflects the charging energy consumption of the charging tram or the discharge supply of the discharging tram, collectively referred to as the performance of power supply and demand. At the same time, considering that the temperature of the tram will affect the charging rate of the tram, the electric power supply and demand performance of the tram to the power station can be accurately analyzed by combining the tram's electric power and temperature, and the power supply performance of the tram to the power station is measured by the relative size of the overall power supply performance and overall power consumption of the tram at each moment, thereby obtaining the tram power supply performance degree; the electric power of all batteries at each moment is The battery charge shows the battery's demand for electricity from the power station, and is combined with the grid dependence and the tram power supply performance, that is, the supply and demand performance of photovoltaic power generation, grid, tram and battery are integrated to form a coordinated scheduling mechanism. It can more flexibly respond to complex operating conditions such as tram usage patterns and changes in photovoltaic power generation, provide more accurate energy management strategies, effectively respond to the challenges of complex and rapidly changing power station operating conditions, reasonably predict the demand for electricity from the power station for each battery, dynamically adjust the battery charging and replenishment power, reduce ineffective energy consumption and battery loss, effectively reduce the deep charge and deep discharge phenomenon of the battery, extend the battery life, and improve the stable regulation effect of the photovoltaic energy storage cycle life. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0040] Figure 1 A flowchart of a stable regulation method for extending the cycle life of photovoltaic energy storage provided by one embodiment of the present invention;

[0041] Figure 2 A flow chart of a method for obtaining grid dependence provided by one embodiment of the present invention;

[0042] Figure 3 A flow chart of a method for obtaining power supply and demand performance provided by one embodiment of the present invention;

[0043] Figure 4 A schematic diagram of a computer device for a stabilizing and regulating device for extending the cycle life of photovoltaic energy storage provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0044] To further illustrate the technical means and effectiveness of the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effectiveness of a stable regulation method for extending the cycle life of photovoltaic energy storage, as proposed by the present invention. In the following description, references to different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0045] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0046] The following describes in detail a specific solution of a stable adjustment method for extending the cycle life of photovoltaic energy storage provided by the present invention with reference to the accompanying drawings.

[0047] Example 1:

[0048] This invention proposes a stable regulation method for extending the cycle life of photovoltaic energy storage, please refer to Figure 1 , which shows a flowchart of the steps of a stable regulation method for extending the cycle life of photovoltaic energy storage provided by one embodiment of the present invention, the method comprising:

[0049] Step S1: Obtain the photovoltaic power generation power of the integrated photovoltaic storage and charging / discharging power station at each moment, the electric power and temperature of each electric vehicle at each moment, and the battery power of each battery at each moment; the power station includes electric vehicles of different categories.

[0050] The tram's dashboard displays the tram's battery level in real time. Tram battery systems are typically equipped with temperature sensors, which collect the tram's battery temperature as the tram's temperature. The battery level and temperature of each tram in the integrated photovoltaic, storage, and charging / discharging station are collected at each moment. Smart meters measure the photovoltaic power generation system in the integrated photovoltaic, storage, and charging / discharging station using AC meters or smart meters. The AC meters or smart meters measure the inverter output power as the photovoltaic power generation power, providing the photovoltaic power generation power at each moment. The voltage method is used to determine the battery level of each battery in the integrated photovoltaic, storage, and charging / discharging station's energy storage system at each moment. The term "power level" refers to the percentage of the tram's or battery's current remaining power to its full capacity.

[0051] In the embodiment of the present invention, the data collection frequency of photovoltaic power generation, electric vehicle power, temperature and battery power are all the same, and the data collection frequency is set to once every 5 seconds.

[0052] It should be noted that the photovoltaic storage charging and discharging integrated power station can not only charge trams like conventional power stations, but also support tram discharge services. The categories of trams include charging trams and discharging trams; the trams being charged are charging trams, and the trams supplying power to the power station are discharging trams. The trams in the photovoltaic storage charging and discharging integrated power station refer to the trams being charged and supplying power to the power station. In order to reduce the over-discharge of the battery, the tram power range and the battery power range are both set to .

[0053] Step S2: Obtain the grid dependence of each battery at each moment based on the charging demand of each battery and the photovoltaic power generation power at each moment.

[0054] The batteries in a power station's energy storage system can be charged from grid power distribution, photovoltaic power generation, and electric vehicle discharge. Grid power distribution and photovoltaic power generation are the primary options for charging the energy storage batteries. The power station stores the electricity generated by the photovoltaic power generation system in the energy storage system's batteries and supplies this electricity to the charging piles when the electric vehicles are charging. However, photovoltaic power generation is significantly affected by the environment. When the amount of electricity generated by photovoltaic power generation is insufficient and the battery's demand for charging is high, the higher the demand, the more total electricity needs to be drawn from the power station. However, the amount of electricity generated by photovoltaic power generation is insufficient to support the battery's withdrawal, resulting in the battery charging requiring more energy from the grid, making the battery charging more dependent on grid power distribution. Therefore, combining photovoltaic power generation power with the battery's demand for charging can analyze the battery's dependence on grid power distribution at each moment, thereby determining the grid dependence.

[0055] Step S3: Obtain the power supply and demand performance of each tram at each moment based on the tram power and temperature at each moment, and determine the tram power supply performance at each moment based on the relative sizes of the power supply and demand performances of different types of trams at each moment.

[0056] The integrated photovoltaic, storage, charging and discharging power station can not only charge trams like conventional power stations, but also support tram discharge services. For example, users can fully charge their vehicles when electricity prices are low, and then reversely transmit electricity to the grid through the power station when electricity prices are high to earn the price difference. Tram discharge supplies energy to the power station, while tram charging consumes energy from the power station. That is, trams are divided into charging trams and discharging trams, so different trams have different charging needs for power stations.

[0057] The electric power level of a tram reflects the charging energy consumption of a charging tram or the discharge supply of a discharging tram, collectively referred to as the performance of power supply and demand. The energy consumption performance of a charging tram on a power station varies in different states of charge. For example, if the tram's power level is in the fast-charging range, the higher the charging power of the charging tram, that is, the stronger the load demand on the power station, the stronger its power consumption performance on the power station. However, if the tram's power level is not in the fast-charging range, in order to protect the tram's battery, the load demand of the charging tram on the power station must be weaker, and its power consumption performance on the power station is weaker. Within the allowable discharge depth range, the higher the tram's power level, the greater the total energy stored in the discharging tram, the more total power that can be reversely transmitted to the power grid, and the stronger its power supply performance to the power station in terms of energy scale. Therefore, the power supply and demand performance of the tram on the power station can be analyzed based on the tram's power level. Since higher temperatures will increase the chemical reaction rate in the tram's battery, making the tram's actual charging or discharging rate faster, resulting in a higher power supply and demand performance of the tram at a higher temperature for the power station, it is necessary to use the tram's temperature at each moment to adjust its power supply and demand performance for the power station to obtain the power supply and demand performance degree.

[0058] The power supply and demand performance of charging and discharging electric vehicles reflects the overall power consumption and power supply of electric vehicles to the power station. When the overall power supply performance of electric vehicles in the power station is greater than the overall power consumption, the electric vehicle power supply performance is more significant, that is, the discharging electric vehicle supplies more energy to the power station. Therefore, the relative size of the power supply and demand performance of different types of electric vehicles can be used to measure the power supply performance of electric vehicles to the power station, thereby obtaining the electric vehicle power supply performance.

[0059] It should be noted that the charging and power consumption behavior of the trams in the power station may change, so the number of trams of the same type at different times may be different.

[0060] Step S4: Determine the charging power of each battery at each moment based on the battery capacity, grid dependency, and power supply performance of all batteries at each moment.

[0061] The battery charge levels of all batteries at the same moment reflect the power station's need for grid-based energy replenishment. Batteries with greater charge levels have greater discharge capacity, are more capable of meeting the charging needs of electric vehicles, and have lower grid-based energy replenishment requirements. Grid dependence reflects the amount of grid energy required to charge batteries, reflecting the need for grid-based energy replenishment. Power supply performance measures the power station's need for grid-based energy replenishment by measuring the relative power supply and power consumption of electric vehicles to the power station at each moment. Combining these indicators to analyze the power station's need for grid-based energy replenishment, the greater the power demand, the greater the charging power provided by the power grid to the battery. This determines the battery's charging power at each moment.

[0062] This solution integrates the supply and demand performance of photovoltaic power generation, power grid, trams and batteries in an integrated photovoltaic, storage and charging power station to form a coordinated scheduling mechanism. It can more flexibly respond to complex operating conditions such as tram usage patterns and changes in photovoltaic power generation, provide more precise energy management strategies, and effectively respond to the challenges of complex and rapidly changing power station operating conditions. At the same time, based on the real-time dynamic changes between different links in the mechanism, it can reasonably predict and schedule the charging needs of each battery in the power station, accurately adjust the charging power of the power grid to replenish the power station batteries, reduce ineffective energy consumption and battery loss, effectively reduce the deep charging and deep discharging phenomenon of the battery, and extend the battery life.

[0063] Preferably, in some possible implementations of the embodiments of the present invention, the method for obtaining the grid dependence can be found in Figure 2 , which shows a flow chart of a method for obtaining grid dependence provided by an embodiment of the present invention, the method comprising:

[0064] Step S210: Obtain the performance deficiency of each battery at each moment.

[0065] The different charging and discharging conditions of different batteries in a photovoltaic storage and charging and discharging integrated power station will result in differences in performance between the batteries. After repeated charging and discharging, the active materials on the electrodes are prone to gradual shedding, powdering, or structural collapse, resulting in performance-deficient batteries with a larger internal resistance than normal batteries, causing more energy to be converted into heat during the battery charging and discharging process, forcing the battery's charging and discharging current to be reduced to avoid overheating. Therefore, the more severe the performance deficiency of a battery, the lower its charge and discharge rate at the same charging power. The method for obtaining the performance deficiency of a battery during charging and discharging is the same. It is only necessary to replace the battery's charging power and charging rate with the discharge power and discharge rate. The following analysis of the battery's performance deficiency takes the battery charging process as an example.

[0066] Preferably, in some possible implementations of the embodiments of the present invention, a method for obtaining performance deficiency includes: obtaining the charging power and charging rate of each battery at each moment; selecting a moment as an example moment and a battery as an example battery, and selecting a reference rate for the example battery at the example moment from the charging rates of each battery other than the example battery at the example moment and the moment before the example moment; the charging power of the corresponding battery at the moment corresponding to the reference rate is equal to the charging power of the example battery at the example moment, and the moment corresponding to the reference rate is closest to the example moment; and normalizing the difference between the mean of all reference rates and the charging rate of each battery at each moment to obtain the performance deficiency of each battery at each moment. It should be noted that batteries with more severe performance deficiency have a lower charging rate at the same charging power; the reference rate refers to the ideal charging rate at the charging power of each battery at each moment. When the difference between the mean of the reference rate and the charging rate of each battery at each moment is larger, it indicates that the charging rate of each battery at each moment is much smaller than the ideal charging rate, and the performance deficiency of each battery at each moment is more severe.

[0067] In the embodiment, the Norm function is used for normalization processing, and normalization methods such as function conversion, maximum and minimum normalization, etc. can also be selected, which are not limited here.

[0068] A current sensor and a voltage sensor are installed on each battery of the energy storage system of the integrated photovoltaic, storage and charging / discharging power station to collect the current and voltage of each battery at each moment, and at the same time obtain the battery capacity of each battery; the product of the current and voltage of each battery at each moment is used as the charging power, and the ratio of the current to the battery capacity of each battery at each moment is used as the charging rate.

[0069] Note that each battery can select at most one reference rate from the charging rates of all other batteries at the sample time. To ensure the reliability of the reference rate selected from the other batteries, the reference rate must be closest to the sample time. The reference rate for each battery at the sample time is obtained using the same method.

[0070] In another embodiment of the present invention, the ratio of the charging rate to the charging power of each battery at each moment is calculated, and the ratio is negatively correlated and normalized to obtain the performance deficiency of each battery at each moment. It should be noted that because the ratio of the charging rate to the charging power represents the charging rate of the battery corresponding to a unit charging power, the smaller the ratio, the more serious the battery performance deficiency, so the ratio needs to be negatively correlated. In this embodiment of the present invention, based on the ratios of all batteries at each moment, the ratios of each battery at each moment are normalized using maximum and minimum normalization, and the difference between the constant 1 and the normalized result is used as the performance deficiency of each battery at each moment.

[0071] Step S220: obtaining the charging demand of each battery at each moment according to the difference between the battery power of each battery at each moment and the preset safety power and the performance deficiency.

[0072] Since a battery with more severe performance deficiency has a slower charging rate at the same charging power, it needs to obtain higher charging current more frequently to compensate for the reduction in its available energy, resulting in a higher charging demand. Therefore, the performance deficiency and charging demand are positively correlated.

[0073] To ensure the battery's adequate response to sudden large charging demands and protect its lifespan, the battery charge must be maintained stably at a preset safety level. This preset safety level can be used to divide the battery's charge range into a front sub-range and a back sub-range. The battery charge in the front sub-range is less than or equal to the preset safety level, while the battery charge in the back sub-range is greater than the preset safety level. During charging, when the battery charge is in the front sub-range, or low charge state, the battery's response to sudden large charging demands at the power station is limited. To quickly escape this low charge state, the battery has a high charge demand, resulting in a positive correlation between the difference between the battery charge and the preset safety level and the charging demand. When the battery charge is in the back sub-range, or high charge state, the high charge state reduces battery lifespan. To protect battery lifespan, the battery charge should enter a high charge state, which has a lower charge demand. The difference between the battery charge and the preset safety level and the charging demand is negatively correlated.

[0074] In a specific implementation of the embodiment of the present invention, the charging demand is expressed as follows:

[0075]

[0076] Where U is the charging demand of each battery at each moment; G is the performance deficiency of each battery at each moment; P is the battery capacity of each battery at each moment; A is the preset safety capacity; case 1 is the front subinterval, and case 2 is the back subinterval. In this embodiment, case 1 and case 2 can be expressed as follows: 、 ; is the absolute value function; Norm is the normalization function; It is a preset positive number. Its function is to make the fraction meaningless if the denominator is zero. In this embodiment, the empirical value is 0.1.

[0077] In one implementation of the embodiment of the present invention, the preset safety power is set to 60%.

[0078] Step S230: Obtain the grid dependency of each battery at each moment based on the photovoltaic power generation power and charging demand at each moment.

[0079] It is known that when the amount of electricity generated by photovoltaic power generation is insufficient and the battery's demand for charging is higher, the battery charging needs to draw more electricity from the grid, indicating that the battery charging is more dependent on the grid distribution. In addition, under the same conditions except for the photovoltaic power generation, the smaller the photovoltaic power generation, the less electricity it can generate. Therefore, the photovoltaic power generation is negatively correlated with the grid dependence, and the charging demand is positively correlated with the grid dependence. In the embodiment of the present invention, the photovoltaic power generation at each moment is compared with the preset positive number. The product of the reciprocal of the sum and the charging demand of each battery at each moment is taken as the grid dependence of each battery at each moment.

[0080] In the embodiment of the present invention, the correlation between photovoltaic power generation power and charging demand and grid dependence can also be constructed through other basic mathematical operations, which are not limited or elaborated here.

[0081] Preferably, in some possible implementations of the present invention, the method for obtaining the power supply and demand performance degree can be found in Figure 3 , which shows a flow chart of a method for obtaining power supply and demand performance provided by an embodiment of the present invention, the method comprising:

[0082] Step S310: Calculate the sum of the squares of the differences between the electric power of each charging vehicle at each moment and the median and minimum values ​​of the preset fast charging range, perform negative correlation on the square root of the sum of squares and perform normalization processing to obtain the charging consumption performance of each charging vehicle at each moment.

[0083] In one implementation of the embodiment of the present invention, the preset fast charging zone range is set to The median and minimum values ​​of the preset fast charging range represent the 20% and 50% charge states of the charging electric vehicle respectively.

[0084] In the embodiment of the present invention, the charging consumption performance is expressed by the formula: Where, is the charging consumption performance of each charging electric vehicle at the hth moment; is the absolute value of the difference between the electric capacity of each charging electric vehicle at the hth moment and the electric capacity of the electric vehicle corresponding to the midpoint of the preset fast charging interval; It is the absolute value of the difference between the electric power of each charging electric vehicle at the hth moment and the electric power of the electric vehicle corresponding to the left endpoint of the preset fast charging interval; exp is an exponential function with a natural constant as the base.

[0085] It should be noted that when the electric vehicle's charge level is within the preset fast-charging range, the charging rate of the electric vehicle is close to the maximum value, and the closer it is to the midpoint of the range, the higher the instantaneous charging power, and the greater the real-time energy consumption of the power station; at the same time, the closer the electric vehicle's charge level is to the left end point of the range, the more energy needs to be charged, the longer the total charging time and cumulative power consumption, indicating that the electric vehicle's ability to continuously consume power station energy in the future will be stronger. The following analysis is conducted based on specific data: in the first half of the range Within the range, for the power equal to the upper quartile 35% of the interval, such as 30% and 40%, 30% has a larger continuous power consumption for the power station and a smaller instantaneous charging consumption than 40%, and 35% has a larger continuous power consumption and instantaneous charging consumption for the power station. In this embodiment, it is believed that 30% and 40% have the same power consumption performance for the power station, and 35% has the largest power consumption performance for the power station; compared with the preset fast charging interval , and The power consumption of the power station and the instantaneous charging consumption are both small, but Compare If the power consumption of the power station is large, and The power consumption of the power station is less than that of the preset fast charging interval, and Compare The power consumption of the power station is large.

[0086] Step S320: normalizing the electric quantity of each discharging electric vehicle at each moment to obtain the discharge supply performance of each discharging electric vehicle at each moment.

[0087] It should be noted that within the allowable discharge depth range, the higher the tram charge, the greater the total energy stored in the discharged tram, the more total electricity that can be reversely transmitted to the power grid, and the stronger its power supply performance to the power station in terms of energy scale. The tram charge of the discharged tram is positively correlated with its power supply performance.

[0088] In the embodiment, the Norm function is used for normalization processing, and normalization methods such as function conversion, maximum and minimum normalization, etc. can also be selected, which are not limited here.

[0089] Step S330: Record the charging consumption performance and the discharging supply performance as initial supply and demand performance, adjust the initial supply and demand performance using the temperature of each electric vehicle at each moment, and obtain the power supply and demand performance of each electric vehicle at each moment.

[0090] Preferably, in some possible implementations of the embodiments of the present invention, the method for calculating the power supply and demand performance includes: calculating the ratio of the temperature of each electric vehicle at each moment to the maximum temperature of electric vehicles of its category, and weighting the initial power supply and demand performance using the difference between a constant 1 and the ratio to obtain the power supply and demand performance of each electric vehicle at each moment. It should be noted that for two electric vehicles charging or discharging with the same amount of electricity, the charging electric vehicle with the higher temperature has a faster actual charging rate, so its actual power consumption performance for the power station in the short term should be higher. High temperatures will increase the discharge rate of the discharging electric vehicle, and the higher temperature discharging electric vehicle will deliver more electricity to the grid in the same period of time, causing its actual discharge supply performance for the power station to be higher. Therefore, the higher the temperature of the electric vehicle, the higher the power supply and demand performance for the power station, and the lower the actual power supply and demand performance should be. The lower the temperature of the electric vehicle, the more realistic the power supply and demand performance for the power station, and the actual power supply and demand performance is less than and closer to the actual power supply and demand performance. It is necessary to adjust the initial power supply and demand performance using the result of negative correlation and normalization of the electric vehicle temperature to make the electric vehicle's power supply and demand performance for the power station closer to the actual situation.

[0091] Preferably, in some possible implementations of the embodiments of the present invention, the method for obtaining the power supply performance includes: calculating the cumulative sum of the power supply and demand performance of all electric vehicles of each category at each moment as the overall supply and demand value of each category of electric vehicles at each moment; taking the ratio of the overall supply and demand values ​​of the discharging electric vehicles to the charging electric vehicles at each moment as the initial power supply performance of the electric vehicles to the power station at each moment; and adjusting the initial power supply performance of each moment using the initial power supply performance of the adjacent moments of each moment to obtain the power supply performance of the electric vehicles at each moment. It should be noted that the overall supply and demand value of each category of electric vehicles represents the overall power consumption or overall power supply of the electric vehicles of that category to the power station. In this embodiment, the ratio of the overall power supply of the supplying electric vehicles to the overall power consumption of the charging electric vehicles is used to measure the power discharge and charge ratio of the electric vehicles to the power station. When the power discharge and charge ratio is larger, the power supply of the electric vehicles to the power station is greater than the power consumption, making the power supply performance of the electric vehicles to the power station more obvious and the initial power supply performance greater. At the same time, in order to avoid abnormal situations in the power supply performance analysis of the tram to the power station at each moment, this embodiment performs a straight line fitting on the initial power supply performance at each moment and its adjacent moments, and uses the data at the corresponding position on the fitting line at each moment as the power supply performance at each moment, thereby reducing the impact of abnormal situations on the power supply analysis.

[0092] In one implementation of the embodiment of the present invention, the first 10 moments adjacent to each moment are taken as its adjacent moments.

[0093] In another embodiment of the present invention, the product of the total number of trams of each category at each moment and the average value of the power supply and demand performance of all trams at each moment is used as the tram power supply performance at each moment.

[0094] Preferably, in some possible implementations of the embodiments of the present invention, the method for obtaining the charging replenishment power includes: calculating the average battery power of all batteries at each moment; obtaining the replenishment demand of each battery at each moment based on the grid dependence, power supply performance and the average; using the replenishment demand to weight the preset replenishment power to obtain the charging replenishment power of each battery at each moment.

[0095] It should be noted that if the mean value of the battery charge of all batteries at each moment is smaller, the battery's demand for electricity replenishment from the power station is higher; if the power supply performance is smaller, it indicates that the electric vehicle's power supply to the power station is much less than the power consumption of the power station. The more energy the electric vehicle consumes from the batteries in the power station, the higher the battery's demand for electricity replenishment from the power station; if the grid dependence is greater, the battery charging needs to extract more electricity from the grid, and the battery's demand for electricity replenishment from the power station is higher. Therefore, the grid dependence is positively correlated with the energy replenishment demand, and the power supply performance is negatively correlated with the mean value and the energy replenishment demand. In an embodiment of the present invention, the mean value of the battery charge of all batteries at each moment is negatively correlated with the product of the battery's power supply performance to the power station, and the mapping result is normalized with the product of the grid dependence of each battery at each moment to obtain the energy replenishment demand of each battery at each moment. The higher the demand for power replenishment of the power station battery from the grid, that is, the greater the replenishment demand, the greater the battery charging power should be to meet the charging demand of the power station battery. The replenishment demand can be used to dynamically adjust the charging power of the power station battery to avoid overcharging or over-discharging of the battery in the integrated photovoltaic, storage, charging and discharging power station, thereby extending the battery life.

[0096] In a specific implementation of the embodiment of the present invention, the charging power is expressed as follows:

[0097]

[0098] Where, is the charging power of each battery at the hth moment; is the grid dependence of each battery at the hth moment; IJ is the electric vehicle power supply performance at the hth moment; is the average battery capacity of all batteries at the hth moment; BW is the preset charging power; exp is an exponential function with a natural constant as the base; Norm is a normalization function. It should be noted that this embodiment uses the exp function to compare IJ with Perform negative correlation mapping and use the Norm function for normalization. You can also choose normalization methods such as maximum and minimum normalization and negative correlation mapping methods such as taking the inverse.

[0099] In one implementation of the embodiment of the present invention, the preset energy replenishment power is set to 10 kilowatts.

[0100] So far, the present invention is completed.

[0101] Example 2:

[0102] The present invention also proposes a computer device schematic diagram of a stable regulation device for extending the cycle life of photovoltaic energy storage, please refer to Figure 4 The computer device includes a memory 501, a processor 502, and a computer program 503 stored in the memory 501 and running on the processor 502. When the processor 502 executes the computer program 503, the computer device can execute any of the aforementioned stable adjustment methods for extending the cycle life of photovoltaic energy storage.

[0103] In addition, an embodiment of the present application also protects a device, which may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to execute a stable adjustment method for extending the cycle life of photovoltaic energy storage provided by an embodiment of the present application.

[0104] In this embodiment, the device can be divided into functional modules based on the above-described method examples. For example, each functional module can be mapped to a specific functional module, or two or more functions can be integrated into a single processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only a logical functional division. In actual implementation, other division methods may be used.

[0105] In the case of dividing the modules into modules corresponding to their functions, the device may further include a communication module, a signal analysis module, a complexity analysis module, a positioning module, etc. It should be noted that all relevant contents of the various steps involved in the above method embodiment can be referred to the functional description of the corresponding functional modules and will not be repeated here.

[0106] It should be understood that the device provided in this embodiment is used to execute the above-mentioned stable adjustment method for extending the cycle life of photovoltaic energy storage, and thus can achieve the same effect as the above-mentioned implementation method.

[0107] In the case of an integrated unit, the device may include a processing module and a storage module. When the device is applied to a device, the processing module may be used to control and manage the operation of the device. The storage module may be used to support the device in executing mutual program codes, etc.

[0108] The processing module may be a processor or controller that implements or executes the various exemplary logic blocks, modules, and circuits disclosed herein. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processor (DSP) and a microprocessor, and the like. The storage module may be a memory.

[0109] Example 3:

[0110] This embodiment also provides a computer-readable storage medium, which stores computer program code. When the computer program code is run on a computer, the computer executes the above-mentioned related method steps to implement a stable adjustment method for extending the cycle life of photovoltaic energy storage provided by the above embodiment.

[0111] Example 4:

[0112] This embodiment also provides a computer program product. When the computer program product is run on a computer, it enables the computer to execute the above-mentioned related steps to implement a stable adjustment method for extending the cycle life of photovoltaic energy storage provided by the above embodiment.

[0113] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0114] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0115] It should be noted that the order in which the embodiments of the present invention are described above is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0116] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

Claims

1. A stable regulation method for extending the cycle life of photovoltaic energy storage, characterized in that: The method includes: Obtaining the photovoltaic power generation power of the photovoltaic storage charging and discharging integrated power station at each moment, the electric vehicle power and temperature of each electric vehicle at each moment, and the battery power of each battery at each moment; the power station includes different types of electric vehicles; Obtaining the grid dependence of each battery at each moment based on the charging demand of each battery at each moment and the photovoltaic power generation power; Obtaining a power supply and demand performance of each tram at each moment based on the tram power and temperature of each tram at each moment, and determining a tram power supply performance at each moment based on the relative magnitudes of the power supply and demand performances of different types of trams at each moment; Determining the charging power of each battery at each moment according to the battery power of all batteries at each moment, the grid dependence, and the power supply performance; The obtaining of the power supply and demand performance of each electric vehicle at each moment includes: The types of trams include charging trams and discharging trams; Calculating the sum of the squares of the differences between the electric power of each charging electric vehicle at each moment and the median and minimum values ​​of the preset fast charging range, performing negative correlation and normalization on the square roots of the sums of squares, and obtaining the charging consumption performance of each charging electric vehicle at each moment; Normalize the electric quantity of each discharging tram at each moment to obtain the discharge supply performance of each discharging tram at each moment; Recording the charging consumption performance and the discharging supply performance as initial supply and demand performance, adjusting the initial supply and demand performance using the temperature of each electric vehicle at each moment, and obtaining the power supply and demand performance of each electric vehicle at each moment; Determining the electric vehicle power supply performance at each moment includes: Calculate the cumulative sum of the power supply and demand performance of all electric vehicles of each category at each moment as the overall supply and demand value of each category of electric vehicles at each moment; take the ratio of the overall supply and demand value of the discharging electric vehicles to the charging electric vehicles at each moment as the initial performance of the electric vehicles' power supply to the power station at each moment; The initial power supply performance degree at each moment is adjusted by using the initial power supply performance degree at the adjacent moments to obtain the electric vehicle power supply performance degree at each moment.

2. A stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 1, characterized in that: The obtaining of the grid dependency of each battery at each moment includes: Get the performance deficiency of each battery at each moment; Obtaining a charging demand for each battery at each moment based on a difference between the battery power of each battery at each moment and a preset safety power and the performance deficiency; The grid dependence of each battery at each moment is obtained based on the photovoltaic power generation power and the charging demand at each moment; the photovoltaic power generation power and the grid dependence are negatively correlated, and the charging demand and the grid dependence are positively correlated.

3. A stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 2, characterized in that: The method for obtaining the charging demand degree includes: The battery power range is divided into a front sub-range and a rear sub-range based on a preset safety power; if the battery power of each battery at each moment is within the front sub-range, the difference and the charging demand are positively correlated; if the battery power of each battery at each moment is within the rear sub-range, the difference and the charging demand are negatively correlated.

4. A stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 1, characterized in that: Determining the charging power of each battery at each moment includes: Calculating the average battery power of all batteries at each moment; obtaining the energy replenishment requirement of each battery at each moment based on the grid dependence, the power supply performance, and the average; the grid dependence is positively correlated with the energy replenishment requirement, and the power supply performance and the average are negatively correlated with the energy replenishment requirement; The preset energy replenishment power is weighted using the energy replenishment demand to obtain the charging energy replenishment power of each battery at each moment.

5. A stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 2, characterized in that: The method for obtaining the performance deficiency degree includes: Get the charging power and charging rate of each battery at each moment; Select any time as an example time and any battery as an example battery, and select a reference rate for the example battery at the example time from the charging rates of each battery except the example battery at the example time and the time before the example time; the charging power of the corresponding battery at the time corresponding to the reference rate is equal to the charging power of the example battery at the example time, and the time corresponding to the reference rate is closest to the example time; The difference between the mean of all reference rates and the charging rate of each battery at each moment is normalized to obtain the performance deficiency of each battery at each moment.

6. A stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 1, characterized in that: The adjusting the initial supply and demand performance using the temperature of each electric vehicle at each moment to obtain the power supply and demand performance of each electric vehicle at each moment includes: The ratio of the temperature of each tram at each moment to the maximum temperature of the trams of its category is calculated, and the initial supply and demand performance is weighted by the difference between a constant 1 and the ratio to obtain the power supply and demand performance of each tram at each moment.

7. A stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 1, characterized in that: The power supply performance index is data at corresponding positions on a fitted straight line obtained by performing straight-line fitting on the power supply initial performance index at each moment and its adjacent moments.

8. The stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 3, characterized in that: The battery power in the front subinterval is less than or equal to the preset safety power, and the battery power in the rear subinterval is greater than the preset safety power.

9. The stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 1, characterized in that: The preset fast charging range is 20% to 80%.

10. A stable regulation method for extending the cycle life of photovoltaic energy storage according to claim 4, characterized in that: The preset energy replenishment power is 10 kilowatts.

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