CN115912447A - A power distribution method and system for an energy storage power station - Google Patents

Abstract

The invention discloses a power distribution method and a power distribution system for an energy storage power station, which belong to the technical field of battery energy storage power stations, and comprise the following steps: obtainingtA scheduling power command at time BESS; to obtaintThe state of abuse of the battery cell, SOC and SOH at the moment, and calculatingtThe SOS of each battery unit at the moment; calculating a charge and discharge judgment value of the battery unit according to the SOC and the SOH; generating a battery unit charging and discharging criterion table according to the SOC, the SOS and the battery unit charging and discharging judgment value; calculating according to the charging and discharging criteria of the battery unittThe number of PCS actions at the moment; solving PCS power needing to act according to the number of PCS acts, and issuing a scheduling power instruction; according to scheduling power instruction calculationtSOC at +1 time, repeatedly calculated until a set periodTAnd when the operation is finished at all the moments, summarizing and scheduling the power instruction to obtain an energy management strategy. Such an extensionThe performance attenuation of the battery is slowed, and the service life of the energy storage system is prolonged.

Description

A power distribution method and system for an energy storage power station

technical field

The invention belongs to the technical field of battery energy storage power stations, and mainly relates to a power distribution method and system of an energy storage power station.

Background technique

With the rapid development of new energy, the battery energy storage system (Battery Energy Storage System, referred to as BESS) is more and more widely used in the power system. If lithium-ion batteries are used, the higher the number of batteries, the higher the energy density, which may increase the safety risk. Therefore, the safety of the battery should be considered in the energy management of BESS. There is little research on energy management based on battery safety state.

How to numerically quantify energy storage battery safety is an imprecise task that often requires interpretation. One of the ways to classify the safety of energy storage batteries is by hazard level, as shown in Table 1. A higher level assumes that the previous level has already taken place. For example, when a fire occurs, assuming that liquid leakage or exhaust also occurs, the fire is more serious than them at this time, but not as serious as the explosion of the next level. At the time of the test, the rating should not exceed 4, i.e. the device being tested should not exhibit severe rupture, fire or explosion, as these would pose a clear hazard to personnel handling the battery. Level 4 hazard levels may render the device unusable, but they do not put users at greater risk.

Table 1 Hazard levels of batteries

According to the concept that safety is inversely proportional to the abuse concept, the definition and calculation method of the safety state of energy storage system. Is the state parameter of the lithium-ion battery, indicating the health and remaining energy state of the battery. The safety state of the battery should be inversely proportional to the abuse degree of the battery, as follows:

(1)

In the formula, is an abused state, That is, SOS, x represents all types of state and control variables that describe the behavior of the battery at a given time t , such as voltage, temperature, current, internal resistance, mechanical deformation of the battery, and so on. In this formula, as the abuse increases, the security status will decrease accordingly. Security state is a value from 0-1. The absolute value of abuse becomes infinite, the safe value should tend to 0 or not safe at all, and when the abuse is absent or zero, the safe should be limited to 1 or completely safe.

Chinese patent application CN113131503A discloses an energy management method for energy storage power stations based on SOC consistency of multi-battery packs. This method optimizes the power distribution of multi-battery packs in energy storage power stations, and adjusts the batteries in real time through algorithm control in each scheduling cycle. The difference between charging and discharging power distribution and SOC; specifically, firstly, the overall output power is calculated based on the dispatching instructions of the energy storage power station, and then the SOC variance, fluctuation rate and battery life of each energy storage battery pack are used as optimization goals, and the charge and discharge of each battery pack The number of state switching and the power distribution size are optimization variables. Using the genetic algorithm, the optimal solution for the control of the energy storage system is obtained, and the SOC adjustment of the battery pack of the energy storage power station is completed.

This method only considers the SOC variance, fluctuation rate and battery life of each energy storage battery pack as the optimization goal, and realizes the charge and discharge power distribution of the energy storage system, so that the SOC of multiple battery packs tends to be consistent within the dispatch cycle. The disadvantage is that the number of PCS actions is not considered, which may easily lead to low operating efficiency of the system. And it does not consider the security state of the system, and cannot reduce the probability of system security accidents.

Chinese patent application CN114094611A provides a method and system for dispatching power command distribution of energy storage power stations considering SOC consistency. Including: if a frequency modulation command and AGC power adjustment control command exceed the available power of the whole station, the value of the frequency modulation command and AGC power regulation control command is corrected to the available power of the whole station; otherwise, the current SOC of the battery stack corresponding to each PCS of the energy storage station is obtained The difference between the SOC value and the preset target SOC value is determined based on the primary frequency modulation instruction, the AGC power regulation control instruction, and the difference to determine the charge/discharge scheduling power instruction assigned by each PCS. It aims to achieve further fine-grained control of the battery SOC, and realize the convergent adjustment of the SOC of the battery stacks with different initial SOCs by participating in daily charging and discharging, that is, to further improve the consistency of the SOC of each battery stack, and at the same time to meet the full capacity response The SOC is adjusted for peak load regulation and valley fill demand of the power grid.

The PCS power allocation method does not take into account the number of PCS actions, which easily leads to low system operation efficiency. And it does not consider the security state of the system, and cannot reduce the probability of system security accidents.

Contents of the invention

Aiming at the prior art, the present invention provides a power distribution method and system for an energy storage power station. The method is a power distribution method for an energy storage power station obtained after considering the safety status of battery units. This method can make energy storage units with lower SOS The units with less burden and SOS lower than the threshold are repaired, so as to delay the performance decay of the battery and prolong the service life of the energy storage system.

In order to achieve the above object, the present invention adopts the following technical solutions to achieve:

A power distribution method for an energy storage power station, comprising:

S1, obtaining the dispatching power command of the BESS at time t ;

S2, obtain the abuse state, SOC and SOH of the battery unit at time t , and calculate the SOS of each battery unit at time t ;

S3, calculate the battery cell charge and discharge judgment value according to SOC and SOH ;

S4, according to SOC, SOS, battery cell charge and discharge judgment value Generate battery cell charge and discharge criterion table;

S5, calculate the number of PCS actions at time t according to the battery unit charging and discharging criterion table;

S6. Solve the PCS power required for action according to the number of PCS actions, and issue a scheduling power instruction;

S7. Calculate the SOC at time t +1 according to the dispatching power instruction, repeat S1~S6, until the calculation at all times in the set period T is completed, and summarize the dispatching power instruction to obtain the energy management strategy.

As a further improvement of the present invention, in said S1, the dispatching power command of the BESS at time t is obtained ,when When, BESS is in discharge mode; when , BESS is charging mode.

As a further improvement of the present invention, in said S3, calculating the charge and discharge judgment value of the battery cell according to the SOC and SOH includes:

Measure the initial SOC of the battery unit, set the charge and discharge reference value SOC _ref , and calculate the charge and discharge judgment value of the i -th battery unit at time t ;

The SOC reference value of each battery cell is ,but ;

Among them, SOH _i is the SOH of the i- th battery cell, is the state of charge of the i -th battery cell at time t .

As a further improvement of the present invention, in said S4, according to SOC, SOS, battery cell charge and discharge judgment value Generate battery cell charge and discharge criteria table, including:

According to SOC, battery cell charge and discharge judgment value Generate a preliminary battery unit charge and discharge criterion table, and then delete the data of the battery unit whose SOS is less than the safety standard value, and obtain the final battery unit charge and discharge criterion table.

As a further improvement of the present invention, in said S5, the number of PCS actions at time t is calculated according to the battery unit charge and discharge criterion table, including:

When the energy storage dispatch command power When discharge is required, according to The values are sorted from large to small and from top to bottom; calculate from the first row and then calculate the maximum discharge capacity based on the power limit of each battery cell , until the maximum discharge capacity is greater than or equal to the absolute value of the total dispatching power command ,make , the number of charging units is obtained as ;

when when charging is required, yes The columns are sorted from small to large and from top to bottom; calculate from the first row and then calculate the maximum charging capacity based on the power limit of each battery cell That is, until the maximum charging amount is greater than or equal to the absolute value of the total dispatched power command ,make , the number of discharge cells is obtained as: ;

Then the number of PCS actions at time t is obtained.

As a further improvement of the present invention, in said S6: solve the PCS power that needs to act according to the number of PCS actions, and use an optimization solver for the solution; the SOC consistent objective function in the optimization solver is:

in, is the number of PCS actions at time t; is the state of charge of the i -th battery cell at time t, is the SOC reference value of battery cell i ;

Constraints include:

(1) The battery cell SOC constraint is

in, , are the maximum and minimum allowable SOC of the battery cell corresponding to the i -th PCS;

(2) Charge and discharge power constraints

in, is the discharge power of the i- th PCS corresponding to the battery unit at time t , is the charging power of the i- th PCS at time t ; , are the maximum and minimum charging power of the i -th PCS, respectively, , are the maximum and minimum discharge power of the i -th PCS, respectively;

(3) The SOC change constraint is

in, is a time period, S _i is the rated capacity of the battery cell corresponding to the ith PCS, is the actual capacity of the battery unit corresponding to the i- th PCS, the energy storage scheduling command power is greater than 0 is the discharge mode, and less than 0 is the charge mode;

(4) The charge and discharge power conservation constraint is

The power of each PCS is obtained by solving the objective function and constraint conditions.

A power distribution system for an energy storage power station, comprising:

The communication module is used to obtain the dispatching power command of the BESS at time t ;

The data acquisition module is used to obtain the battery unit abuse state, SOC and SOH at time t , and calculate the SOS of each battery unit at time t ;

The safe state calculation module is used to calculate the charge and discharge judgment value of the battery unit according to the SOC and SOH ;

PCS action judging module, used for judging value according to SOC, SOS, battery cell charge and discharge Generate battery cell charge and discharge criterion table;

An optimization solver is used to calculate the number of PCS actions at time t according to the battery cell charge and discharge criterion table;

The power allocation execution module is used to solve the PCS power required for action according to the number of PCS actions, and issue a dispatch power command;

The state of charge calculation module is used to calculate the SOC at time t + 1 according to the dispatching power command, until the calculation of all time in the set period T is completed, and the energy management strategy is obtained by summarizing the dispatching power command.

As a further improvement of the present invention, in the BESS, every n PCSs and transformers form a transformer unit, a total of m transformer units are connected to the power grid, and there are A total of A PCSs in the BESS, where A=n*m.

An electronic device, comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, when the processor executes the computer program, the power distribution method of the energy storage station is implemented step.

A computer-readable storage medium, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the power distribution method of the energy storage station are realized.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention takes the SOC, SOH and SOS of the battery unit as input, first determines the PCS charging and discharging sequence according to the SOC, SOH and SOS in each period, and then makes the battery unit charging and discharging criterion table, and calculates and determines the PCS charging/discharging according to the table and select which PCS actions. Finally, the information of these PCS is input into the optimization solver to obtain the power of each action PCS.

Description of drawings

Fig. 1 is the power distribution system of the energy storage power station considering the safety state of the battery unit in the present invention;

Fig. 2 is a BESS topology diagram of the present invention;

Fig. 3 is a flow chart of the power distribution method of the energy storage power station considering the safety status of the battery units in the present invention;

Fig. 4 is the power distribution under certain cloudy conditions provided by the embodiment of the present application;

Fig. 5 is the SOC (different SOH) of each battery cell provided by the embodiment of the present application;

Fig. 6 is the SOC of the safety failure unit and the normal battery unit with the same SOH provided by the embodiment of the present application;

Fig. 7 is the SOS to PCS charging/discharging power limitation provided by the embodiment of the present application;

Fig. 8 is a schematic diagram of an electronic device provided by the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only It is an embodiment of a part of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

It should be noted that the terms "first" and "second" in the description and claims of the present invention and the above drawings are used to distinguish similar objects, but not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or device comprising a sequence of steps or elements is not necessarily limited to the expressly listed instead, may include other steps or elements not explicitly listed or inherent to the process, method, product or apparatus.

With the increase in the scale of battery energy storage, safety issues have become a new risk and challenge for the development of energy storage. Timely attention should be paid to safety risk management, and research on battery energy storage safety issues should be carried out.

In large-scale energy storage power stations, it is affected by the manufacturing process. As charge and discharge cycles increase, it can be difficult to ensure cell consistency. The inconsistency of battery cells and the "short plate effect" limit the scale of BESS, making it impossible to realize the large-scale application of battery energy storage through simple electrical connections. Therefore, for large-scale BESS, a battery management system (battery management system, BMS) that also considers safety and battery consistency becomes the key.

In order to consider the state of charge (SOC), state of health (SOH) and safety state (SOS) at the same time, the invention provides a method and system for power distribution of energy storage power stations considering the safety state of battery cells, which can make the consistency of BESS better , and avoid security risks to a certain extent.

The first object of the present invention is to provide a power distribution method for an energy storage power station, including:

S1, obtaining the dispatching power command of the BESS at time t ;

S2, obtain the abuse state, SOC and SOH of the battery unit at time t , and calculate the SOS of each battery unit at time t ;

S3, calculate the battery cell charge and discharge judgment value according to SOC and SOH ;

S4, according to SOC, SOS, battery cell charge and discharge judgment value Generate battery cell charge and discharge criterion table;

S5, calculate the number of PCS actions at time t according to the battery unit charging and discharging criterion table;

S6. Solve the PCS power required for action according to the number of PCS actions, and issue a scheduling power command;

S7. Calculate the SOC at time t +1 according to the dispatching power instruction, repeat S1~S6, until the calculation at all times in the set period T is completed, and summarize the dispatching power instruction to obtain the energy management strategy.

The present invention aims at SOC consistency, and at the same time determines the power range of the PCS according to the SOS. This method guarantees the safe operation of the system to a certain extent, has a good SOC balance effect, and the BESS can better adjust the degree. The SOC of the same SOH battery energy storage unit can be maintained at the same level by using the power distribution method and system of the energy storage power station considering the safety state of the battery unit proposed by the present invention. The control method and system can reduce the burden on energy storage units with lower SOS, and repair the units whose SOS is lower than the threshold, so as to delay the performance decay of the battery and prolong the service life of the energy storage system.

The present invention will be described in detail below through specific examples.

Example 1

The specific implementation of the present invention provides a power distribution system of an energy storage power station considering the safety state of battery units. As shown in Figure 1, the system includes: a communication module, a data acquisition module, a safety state calculation module, a PCS action judgment module, and an optimization solver , a power distribution execution module and a state of charge calculation module.

The topological structure of the BESS used in the present invention is shown in Figure 2: every n PCSs and transformers form a transformer unit, and a total of m transformer units are connected to the power grid. BESS has a total of A PCS (A=n*m).

The specific implementation of the present invention provides a power distribution method of an energy storage power station considering the safety state of battery units, including:

Step 1: Obtain the dispatching power command of the BESS through the communication module at time t .

Step 2: The data acquisition module measures the battery unit abuse state, SOC and SOH, and calculates the SOS of each battery unit at this moment in the safe state calculation module.

Step 3: Calculate the charge and discharge judgment value of the battery unit according to the SOC and SOH of the battery unit.

Step 4: Make a battery unit charge and discharge criterion table according to the SOC and the battery unit charge and discharge judgment value, first delete the battery unit whose SOS is less than the safety standard value, and then sort the battery unit charge and discharge order according to the battery unit charge and discharge judgment value;

Step 5: Calculate the number of PCS actions per period (steps 3-5 are completed in the PCS action judgment module);

Step 6: Solve the PCS power that needs to be acted on in the optimization solver, and issue a scheduling power command to the power allocation execution module;

Step 7: Calculate the SOC at the next moment in the state of charge calculation module, and repeat steps 1-6 until the operation is stopped. The energy management strategy within this time T can be generated in real time through steps 1-7.

Example 2

As shown in Figure 4, an implementation of the present invention provides a power distribution method for an energy storage power station considering the safety status of battery units, specifically including:

Step 1: Obtain the dispatching power command of BESS at time t ,when When, BESS is in discharge mode; when , BESS is charging mode.

Step 2: Obtain the abuse state, SOC and SOH of the battery unit at time t , and calculate the SOS of each battery unit at time t , where the SOS of battery unit i at time t is .

Step 3: Calculate the charge and discharge judgment value of the battery cell according to the SOC and SOH of the battery cell . First determine the charging and discharging sequence of BESS battery cells, then determine the number of PCS charging/discharging, and finally select which PCS actions.

In step 3, measure the initial SOC of the battery unit and set its charge and discharge reference value , calculate the charge and discharge judgment value of the i -th battery cell within time t . In order to ensure good dispatchability of the battery energy storage system, it is necessary to maintain the SOC of the battery unit with a small SOH at a high level. For this reason, the SOC reference value of each battery cell is , , The larger the value, the battery unit will be discharged first, otherwise the battery unit will be charged first.

Step 4: According to SOC, Make a battery unit charge and discharge criterion table, first delete the SOS less than the safety standard value unit, and then according to Sort the battery cells, The larger the value, the battery unit will be discharged first, otherwise the battery unit will be charged first.

when each period is based on After charging and discharging are sorted, the charging and discharging selection rules are shown in Table 2.

Table 2 PCS Action Judgment Table

First find and delete the unsafe unit in unit A, that is, delete less than line.

Step 5: Calculate the number of PCS actions at time t ;

When the energy storage dispatch command power When the battery energy storage system needs to be discharged, according to The values are sorted from largest to smallest, top to bottom. At this time, the calculation starts from the first line and then calculates the maximum discharge capacity based on the power upper limit of each battery unit, that is , until it is greater than or equal to the absolute value of the total dispatch power command ,make , the number of charging units at this moment is .

when When the battery energy storage system needs to be charged, the The columns are sorted from small to large and from top to bottom. At this time, the calculation starts from the first row and then calculates the maximum charging capacity based on the power limit of each battery unit, that is , until it is greater than or equal to the absolute value of the total dispatch power command ,make , the number of discharge cells at this moment is . The actual number of PCS actions is the number of charging and discharging cells plus 1 to the critical value, which is to leave a certain margin and prevent no solution.

The optimization solver in step 6 is as follows:

SOC consistent objective function:

(2)

Restrictions:

(1) Battery cell SOC constraints

(3)

are the maximum and minimum allowable SOC of the battery cell corresponding to the i- th PCS, respectively.

(2) Charge and discharge power constraints

(4)

(5)

is the discharge power of the ith PCS at time t , are the maximum and minimum discharge power of the i -th PCS, respectively is the charging power of the i- th PCS at time t . is the safety state of the i- th battery unit at time t , and the corresponding PCS power limit of each battery unit is different according to the safety state. The purpose of setting the minimum charge and discharge power limit is to avoid the power of a certain PCS being too small, resulting in low PCS efficiency. Figure 7 shows the SOS to PCS charge/discharge power limit curve. running power. The upper and lower limits of power satisfy the formula:

(6)

(7)

(8)

(9)

(3) SOC change constraints

(10)

(11)

in , is the charging/discharging power of the ith PCS at time t , is a time period, S _i is the rated capacity of the i -th battery cell, is the actual capacity of the i- th battery unit, the energy storage scheduling command power is greater than 0 is the discharge mode, and less than 0 is the charge mode.

(4) Charge and discharge power conservation constraints

This constraint is to represent the energy storage power balance

(13)

(14)

The power of each PCS can be obtained through the objective function and constraints.

The present invention is simulated in the photovoltaic power generation/BESS hybrid power system, wherein the rated power of the photovoltaic power station is 1000MW, the installed capacity of the BESS is 240MW/960MW/h, and the number of PCS is 480, each PCS contains a battery unit, each The maximum power of a PCS is 0.5 MW, and the capacity is 2 MW/h.

Figure 4 shows the power distribution under certain cloudy conditions. As shown in Figure 4, the energy storage power is greater than 0 for discharging, and less than 0 for charging. It can be seen from the figure that the photovoltaic output starts to climb at 8:00 and reaches the maximum value at 11:30. At 18:00 the output is 0. The load reaches its peak at 12:00 and then at 20:00.

Figure 5 shows the SOC of each battery unit. It can be seen that the SOC of each battery unit can be consistent with the method, and battery units with different SOH differentiate into different SOC levels during the operation of the BESS. A unit with a higher SOH, such as SOH=1, will have a lower SOC; a unit with a lower SOH, such as SOH=0.8, will have a higher SOC. This shows that the actual power of each battery unit should be consistent as much as possible, and the scheduling of the system is better.

Figure 6 shows the SOC of the unit with a safety failure and the normal battery unit with the same SOH. When 1000-1030 minutes, the SOS of the battery unit with a safety failure is lower than 0.5, and charging and discharging are not performed during this period. Comparing the normal battery cells with the initial SOH, it can be seen that at 1030-1050 minutes, when the SOS is higher than 0.5, the normal battery cells can be quickly discharged in a short time, and the battery cells achieve good SOC consistency.

As shown in FIG. 8, the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and operable on the processor. When the processor executes the computer program, the The steps of the power distribution method of the energy storage power station.

The power distribution method of the energy storage power station includes the following steps:

S1, obtaining the dispatching power command of the BESS at time t ;

S2, obtain the battery unit abuse status, SOC and SOH at time t , and calculate the SOS of each battery unit at time t ;

S3, calculate the battery cell charge and discharge judgment value according to SOC and SOH ;

S4, according to SOC, SOS, battery cell charge and discharge judgment value Generate battery cell charge and discharge criterion table;

S5, calculate the number of PCS actions at time t according to the battery unit charging and discharging criterion table;

S6. Solve the PCS power required for action according to the number of PCS actions, and issue a scheduling power command;

S7. Calculate the SOC at time t +1 according to the dispatching power instruction, repeat S1~S6, until the calculation at all times in the set period T is completed, and summarize the dispatching power instruction to obtain the energy management strategy.

The present invention further provides a computer-readable storage medium, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the power distribution method of the energy storage station are realized.

The power distribution method of the energy storage power station includes the following steps:

S1, obtaining the dispatching power command of the BESS at time t ;

S2, obtain the battery unit abuse status, SOC and SOH at time t , and calculate the SOS of each battery unit at time t ;

S3, calculate the battery cell charge and discharge judgment value according to SOC and SOH ;

S4, according to SOC, SOS, battery cell charge and discharge judgment value Generate battery cell charge and discharge criterion table;

S5, calculate the number of PCS actions at time t according to the battery unit charging and discharging criterion table;

S6. Solve the PCS power required for action according to the number of PCS actions, and issue a scheduling power command;

S7. Calculate the SOC at time t +1 according to the dispatching power instruction, repeat S1~S6, until the calculation at all times in the set period T is completed, and summarize the dispatching power instruction to obtain the energy management strategy.

Those skilled in the art should understand that the embodiments of the present invention may be provided as methods, systems, or computer program products. Accordingly, the present invention can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and combinations of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a Means for realizing the functions specified in one or more steps of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart flow or flows and/or block diagram block or blocks.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: the present invention can still be Any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention shall fall within the protection scope of the claims of the present invention.

Claims (10)

1. A power distribution method for an energy storage power station is characterized by comprising the following steps:

s1, obtainingtA scheduling power command at time BESS;

s2, obtainingtThe abuse state, SOC and SOH of the battery cell at the moment, and calculatingtThe SOS of each battery unit at the moment;

s3, calculating a charging and discharging judgment value of the battery unit according to the SOC and the SOH

；

S4, judging values according to the SOC, the SOS and the charging and discharging of the battery unit

Generating a battery unit charging and discharging criterion table;

s5, calculating according to the charging and discharging criterion table of the battery unittThe number of PCS actions at the moment;

s6, solving PCS power needing to act according to the number of the PCS acts, and issuing a scheduling power instruction;

s7, calculating according to the scheduling power instructiontThe SOC at the +1 moment repeats S1-S6 until the set time intervalTAnd when the operation is finished at all the moments, summarizing and scheduling the power instruction to obtain an energy management strategy.

2. The energy storage power plant power distribution method of claim 1,

in S1, obtainingtScheduling power commands for time BESS

When is coming into contact with

BESS is the discharge mode; when in use

BESS is the charging mode.

3. The energy storage power plant power distribution method of claim 1,

in S3, calculating a charge/discharge determination value of the battery cell according to the SOC and the SOH includes:

measuring initial SOC of battery unit, and setting charge and discharge reference valueSOC _ref CalculatingtAt a time of dayiCharge and discharge judgment value of each battery cell

；

Each cell SOC reference value is

Then, then

；

wherein ,SOH _i is as followsiOf a battery cellSOH，

Is thattAt the first momentiThe state of charge of each cell.

4. The energy storage power plant power distribution method of claim 1,

in S4, according to SOC, SOS and charge-discharge judgment value of battery unit

Generating a battery unit charging and discharging criterion table, comprising:

according to SOC and battery unit charging and discharging judgment value

And generating a primary battery unit charging and discharging criterion table, and deleting the data of the battery unit with the SOS smaller than the safe standard value to obtain a final battery unit charging and discharging criterion table.

5. The energy storage plant power distribution method of claim 1,

in S5, calculating according to the charging and discharging criterion table of the battery unittThe number of PCS actions at the moment comprises:

scheduling command power when energy storage

When it is necessary to discharge, according to

The values of (A) are sorted from top to bottom from large to small; calculating from the first row and then calculating the maximum discharge amount according to the upper power limit of each battery unit

Until the maximum discharge is greater than or equal to the absolute value of the total scheduled power command

Let us order

Obtaining the number of the charging units as

；

When in use

Need to be charged when necessary, to

The columns are sorted from small to large from top to bottom; the maximum charge is calculated from the first row and then calculated according to the upper power limit of each battery unit

I.e. until the maximum charge is greater than or equal to the absolute value of the total scheduled power command

Let us order

To obtain a discharge cellThe number is as follows:

；

further obtaintNumber of PCS actions at moment.

6. The energy storage plant power distribution method of claim 1,

in the step S6: solving PCS power needing to act according to the number of the PCS actions, wherein an optimization solver is adopted for solving; the SOC consistent objective function in the optimization solver is as follows:

wherein ,

the number of PCS actions at the time t;

is at time tiThe state of charge of the individual battery cells,

is a battery celliThe SOC reference value of (2);

the constraint conditions include:

(1) Cell SOC constraint of

wherein ,

、

are respectively asFirst, theiEach PCS corresponds to a maximum and minimum allowable SOC of the battery cell;

(2) Charge and discharge power constraint

wherein ,

is the firstiA PCS corresponding to the battery unittThe power of the discharge at the moment of time,

is the firstiA PCS istThe charging power at a moment;

、

are respectively the firstiThe maximum and minimum charging power of the PCS is provided,

、

are respectively the firstiMaximum and minimum discharge power of the PCS;

(3) Constraint of SOC variation as

wherein ,

is a time period of time during which,S _i is the firstiOne PCS corresponds to the rated capacity of the battery cell,

is the firstiThe actual capacity of the battery unit corresponding to the PCS is larger than 0, namely a discharging mode, and the actual capacity is smaller than 0, namely a charging mode;

(4) The charge-discharge power conservation is constrained as

And solving through an objective function and a constraint condition to obtain the power of each PCS.

7. An energy storage power station power distribution system, comprising:

communication module for acquiringtA scheduling power command at time BESS;

data acquisition module for obtainingtThe state of abuse of the battery cell, SOC and SOH at the moment, and calculatingtThe SOS of each battery unit at the moment;

a safe state calculating module for calculating the charge and discharge judgment value of the battery unit according to the SOC and the SOH

；

PCS action judging module for judging value according to SOC, SOS and battery unit charging and discharging

Generating a battery unit charging and discharging criterion table;

an optimization solver for calculating according to the charge and discharge criterion table of the battery unittThe number of PCS actions at the moment;

the power distribution execution module is used for solving the PCS power needing to be acted according to the number of the PCS actions and issuing a scheduling power instruction;

a state of charge calculation module for calculating according to the scheduling power instructiontSOC at +1 time until a set periodTAnd when the operation is finished at all the moments, summarizing and scheduling the power instruction to obtain an energy management strategy.

8. The energy storage power plant power distribution system of claim 7,

in the BESS, every n PCS and transformers form one transformer unit, and m transformer units are connected to the power grid in total, wherein the BESS has A PCS in common, and A = n × m.

9. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing the steps of the energy storage plant power distribution method of any of claims 1-6 when executing the computer program.

10. A computer-readable storage medium, storing a computer program which, when executed by a processor, carries out the steps of the energy storage plant power distribution method of any one of claims 1 to 6.

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