Loss calculation method and system for improving primary frequency modulation control precision of energy storage coordination control

Abstract

The invention discloses a loss calculation method for improving energy storage coordination control primary frequency modulation control precision. The method comprises the following steps: step 1, collecting and verifying grid-connected point power and PCS actual output data; 2, based on the data in the step 1, effective data are recorded, and an output comparison table is established; step 3, estimating PCS actual output and loss required by theoretical power based on the output comparison table established in the step 2; and step 4, allocating each PCS for execution based on the actual output and loss of the PCS required by the theoretical power estimated in the step 3, and controlling the power of the grid-connected point to the target power position of the grid-connected point. The primary frequency modulation provided by the invention can realize quick and accurate power control, the open-loop control has no cycle, does not need to wait for feedback, data is stable and does not fluctuate after action, and a primary frequency modulation action curve is closer to a theoretical curve.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage cooperative control primary frequency modulation, and in particular relates to a loss calculation method and system for improving the control accuracy of energy storage cooperative control primary frequency modulation. Background Art

[0002] With the country's strong support and promotion of renewable energy power generation, the installed capacity of renewable energy stations in my country has continued to grow, and its share in the total installed capacity of the entire power system has continued to increase. However, due to the intermittent and random characteristics of photovoltaic and wind power generation, the large-scale grid connection of photovoltaic and wind power has brought huge peak-shaving and frequency-regulating pressure to the grid dispatching, increased the instability of the grid, affected the reliability of power quality, and caused many renewable energy stations to fail to operate normally, resulting in low power generation efficiency.

[0003] With the rapid development of renewable energy power generation, in order to maintain the stable operation of the large power grid, renewable energy power stations must have a primary frequency regulation function, and the response speed of primary frequency regulation has become an urgent problem that needs to be solved by renewable energy stations. In addition, the permanent presence of the primary frequency regulation function also requires renewable energy stations to be in a power-limited state at all times, leaving enough power adjustment space for frequency fluctuations that may occur at any time, which will seriously affect the power generation income of renewable energy stations and increase the operating costs of renewable energy stations.

[0004] On this basis, the energy storage power station matched with new energy sources performs the necessary primary frequency regulation. Since energy storage power stations generally have a faster power response speed than wind power and photovoltaic power stations, this not only meets the power station's demand for rapid primary frequency regulation, but also solves the pain point that power station power limitation affects power generation revenue. It can even increase a lot of revenue by shaving peaks and filling valleys through energy storage power stations. Therefore, energy storage cooperative control needs to have a fast and accurate primary frequency regulation function, which will also become a core function of energy storage cooperative control.

[0005] like Figure 1 The figure shows the layout diagram of a single grid-connected point coordination controller. The primary frequency regulation function is an important assessment content of the energy storage power station. The energy storage coordination control device needs to solve the problem of quickly and accurately calculating the theoretical power of the grid-connected point (also called the assessment point) during the primary frequency regulation process, and calculating the power required by the energy storage PCS (energy storage converter, Power Conversion System) based on the theoretical power. Due to the influence of various factors, such as power consumption within the station, transformer loss, etc., it is very difficult to accurately control the power of the grid-connected point.

[0006] The prior art discloses a method and device for controlling the output of a power grid energy storage system (CN104868488B). After the energy storage system receives the target power dispatching instruction from the power grid side, it starts to obtain the controlled state of each energy storage unit and the actual output value at the overall grid connection point of the energy storage system, and then brings the output value carried by the target power dispatching instruction and the actual output value of the overall grid connection point into the deviation compensation function, obtains the compensation value after calculation, and corrects the target power dispatching instruction according to the compensation value, and finally distributes the corrected dispatching instruction to each controllable energy storage unit for actual power output compensation, thereby completing a feedback control based on a deviation compensation control loop. However, the shortcomings of the prior art are that the traditional loss calculation method has two problems: the first is that it relies too much on fixed functions, and the calculation results are not flexible enough. When the loss in the station changes or the network structure in the station changes, the fixed function often cannot be changed in time, resulting in reduced control accuracy. The second is poor initial frequency modulation accuracy and weak dynamic following performance. This is generally achieved by calculating losses through PID control, which relies too much on real-time data feedback. In the actual ms-level primary frequency modulation scenario, the data feedback speed is far from meeting the response requirements and command change speed of the primary frequency modulation, resulting in slower control speed and affecting the primary frequency modulation assessment. Summary of the invention

[0007] In order to solve the deficiencies in the prior art, the present invention provides a loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control.

[0008] This calculation method focuses on solving the control accuracy in the initial stage of a frequency modulation action or the response accuracy and speed of the grid-connected power when the instructions change frequently.

[0009] The present invention maintains a comparison table of the grid-connected point power and the actual output of the inverter in real time, selects two sets of data closest to the theoretical power when performing primary frequency modulation, and uses a two-point interpolation method to quickly and accurately infer the output required by the inverter, thereby improving the calculation accuracy of the primary frequency modulation loss of the energy storage cooperative control device and realizing precise and flexible open-loop control.

[0010] The present invention adopts the following technical solution.

[0011] A first aspect of the present invention provides a loss calculation method for improving the control accuracy of primary frequency regulation of energy storage cooperative control, comprising:

[0012] Step 1: Collect and verify the grid connection point power and PCS actual output data;

[0013] Step 2: Based on the data in step 1, record the valid data and establish an output comparison table;

[0014] Step 3: Based on the output comparison table established in step 2, estimate the actual output and loss of the PCS required for the theoretical power;

[0015] Step 4: Based on the actual PCS output and loss required by the theoretical power estimated in step 3, each PCS is assigned to execute and the grid connection point power is controlled to the grid connection point target power position.

[0016] Preferably, in step 1, verifying the grid connection point power and the PCS actual output data includes: checking whether a sign error occurs, and whether the grid connection point power is higher than the PCS actual output;

[0017] The correct signs are: negative for charging and positive for discharging.

[0018] Preferably, in step 2, the grid connection point power is divided into intervals for recording the grid connection point power and PCS actual output data in each interval.

[0019] Preferably, in step 2, when recording valid data, a data recording protection mechanism is set, and the data recording protection mechanism includes a new data priority mechanism, a zero-drift data exclusion mechanism, and a full-fill-discharge situation processing mechanism.

[0020] Preferably, the new data priority mechanism is:

[0021] When updating the data of the current interval, determine whether the absolute value of the difference between the data of the adjacent interval and the data of the current interval is less than the set threshold. If it is less than the set threshold, directly clear the data of the adjacent interval and enter the new data to ensure the timeliness of the data.

[0022] Preferably, the mechanism for eliminating zero drift data is:

[0023] When the PCS is completely at zero power, the data in the set value range is shielded.

[0024] Preferably, the full filling and discharging situation handling mechanism is:

[0025] When the energy storage power station is fully charged and discharged, a data recording opening and closing interval mechanism is added. Within the discharge range, if the absolute value of the difference between the interval where the new data is located and the data in the larger interval is less than the set threshold, the new data will not be recorded; if the absolute value of the difference between the interval where the new data is located and the data in the smaller interval is less than the set threshold, then according to the new data priority principle, the data in the smaller interval will be cleared and the new data will be recorded;

[0026] Within the charging range, contrary to the discharging range, if the absolute value of the difference between the interval where the new data is located and the data in the smaller interval is less than the set threshold, the new data will not be recorded. If the absolute value of the difference between the interval where the new data is located and the data in the larger interval is less than the set threshold, the data in the larger interval will be cleared and the new data will be recorded.

[0027] Preferably, in step 3, the calculation process of the actual output of the PCS required for the theoretical power is:

[0028] Exclude the data that is 0, select the two valid records closest to the theoretical power in the output comparison table, and calculate the required PCS actual output through the two-point interpolation method; if all the records are 0 or there are less than two valid records, directly use the PCS theoretical power for output, and refresh the data to the processing comparison table in real time;

[0029] The two-point interpolation formula is:

[0030]

[0031] Where:

[0032] x is the theoretical power; x1 is the grid-connected power of the first group of valid data in the output comparison table that is closer to the theoretical power; y1 is the actual output of the first group of valid data in the output comparison table that is closer to the theoretical power; x2 is the grid-connected power of the second group of valid data in the output comparison table that is closer to the theoretical power; y2 is the actual output of the second group of valid data in the output comparison table that is closer to the theoretical power; y is the actual output of the PCS required for the theoretical power.

[0033] Preferably, in step 3, the loss is the difference between the actual output of the PCS required for the theoretical power and the theoretical power.

[0034] A second aspect of the present invention provides a loss calculation system, which executes the above-mentioned loss calculation method for improving the control accuracy of primary frequency regulation of energy storage cooperative control, including:

[0035] Collection and verification module, output comparison module, PCS actual output and loss estimation module and PCS execution module;

[0036] The acquisition and verification module is used to collect and verify the grid-connected point power and the actual output data of the PCS;

[0037] The output comparison module is used to record the valid data collected by the acquisition and verification module and establish an output comparison table;

[0038] The PCS actual output and loss estimation module is used to estimate the PCS actual output and loss required by the theoretical power;

[0039] The PCS execution module is used to allocate each PCS execution and control the grid connection point power to the grid connection point target power position.

[0040] The beneficial effect of the present invention is that, compared with the prior art,

[0041] (1) The primary frequency modulation provided by the present invention can realize fast and accurate power control. There is no cycle in the open-loop control, and there is no need to wait for feedback. The data after the action is stable and does not fluctuate. The primary frequency modulation action curve is closer to the theoretical curve.

[0042] (2) The loss calculation method provided by the present invention has a certain ability of autonomous error correction and optimization. The data in the current power range will be updated in real time to ensure effectiveness. When the power changes to another range during an action, if the action is inaccurate, but the data in the range has been recorded during the action, the accuracy of the same action next time will be greatly improved.

[0043] (3) The present invention adopts a split design, and data updating and loss calculation are performed independently without interfering with each other. While the loss is estimated based on the data of each power interval, the power interval data is also updated synchronously and independently, thereby improving operational stability and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of the layout of the coordination controller for a single grid connection point;

[0045] Figure 2 It is a data recording flow chart of the present invention;

[0046] Figure 3 Select the flow chart that is closest to the theoretical power range of the present invention;

[0047] Figure 4 This is a schematic diagram of an example of reference data selection for the present invention;

[0048] Figure 5 This is a schematic diagram of the new data priority mechanism of the present invention;

[0049] Figure 6 Schematic diagram of the data isolation mechanism of the present invention. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only embodiments of a part of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0051] The present invention records the previous grid-connected point power and the actual output of the inverter, reasonably and accurately infers the actual output of the inverter corresponding to the current theoretical power of the grid-connected point, and solves the problem of inaccurate rapid control of primary frequency modulation of energy storage cooperative control.

[0052] like Figure 1-6As shown, an embodiment of the present invention provides a loss calculation method for improving the control accuracy of primary frequency regulation of energy storage cooperative control, comprising the following steps:

[0053] Step 1: Collect and verify the grid connection point power and PCS actual output data;

[0054] Collect the grid connection point power and PCS actual output data. Before recording valid data, check whether the grid connection point power and PCS actual output are correct to prevent problems such as sign errors and grid connection point power being higher than PCS actual output.

[0055] Among them, the general situation of correct signs is that charging is negative and discharging is positive; the situation where the power of the grid-connected point is higher than the actual output of the PCS may be due to: sampling errors or incorrect transmission of the actual output of the PCS.

[0056] The grid-connected point power is directly collected by the cooperative control device through the AC sampling module, and the actual PCS output is collected and summarized through the communication between the cooperative control device and the PCS to obtain the AC end output power collected by the PCS itself, while eliminating data interference from faulty PCS and shut down PCS.

[0057] The cooperative control device communicates with each PCS through the GOOSE communication protocol, and the PCS sends actual output and other data to the cooperative control device. The cooperative control device verifies the operating status and active power operating value sent by each PCS, and calculates the total output power of the normally operating PCS.

[0058] In a preferred but non-limiting embodiment of the present invention, the GOOSE control block subscription information is shown in Table 1 below.

[0059] Table 1 GOOSE control block subscription information description table

[0060]

[0061] Step 2: Based on the data in step 1, record the valid data and establish an output comparison table;

[0062] Based on the data verified in step 1, the grid connection point power is divided into intervals to record the grid connection point power and PCS actual output data in each interval. These data will be used to calculate the relationship between theoretical power and actual output, where Pn is the rated power of the grid connection point in KW. The rated power data Pn of the grid connection point is generally determined in the construction design stage and is a fixed value. Under normal circumstances, the power variation range of the grid connection point is between Pn and -Pn. Therefore, this calculation method determines that different proportions of Pn are used as the basis for dividing the intervals.

[0063] In a preferred but non-limiting embodiment of the present invention, the number of grid connection point power intervals is 20, and the division of grid connection point power intervals is shown in Table 2 below.

[0064] Table 2 Comparison of grid connection point power and PCS actual output

[0065] Serial number Interval (grid connection point power) / kW Grid connection point power / kW Actual output / kW 1 +∞~0.9Pn 0 0 2 0.9Pn~0.8Pn 0 0 3 0.8Pn~0.7Pn 0 0 4 0.7Pn~0.6Pn 0 0 5 0.6Pn~0.5Pn 0 0 6 0.5Pn~0.4Pn 0 0 7 0.4Pn~0.3Pn 0 0 8 0.3Pn~0.2Pn 0 0 9 0.2Pn~0.1Pn 0 0 10 0.1Pn~0.0Pn 0 0 11 0.0Pn~-0.1Pn 0 0 12 -0.1Pn~-0.2Pn 0 0 13 -0.2Pn~-0.3Pn 0 0 14 -0.3Pn~-0.4Pn 0 0 15 -0.4Pn~-0.5Pn 0 0 16 -0.5Pn~-0.6Pn 0 0 17 -0.6Pn~-0.7Pn 0 0 18 -0.7Pn~-0.8Pn 0 0 19 -0.8Pn~-0.9Pn 0 0 20 -0.9Pn~-∞ 0 0

[0066] By updating and recording data in daily operation or conducting targeted charging and discharging tests, the cooperative control device can continuously improve and update the output comparison table, so that the device can select the interval closest to the theoretical power for loss assessment during a frequency modulation process, thereby achieving the purpose of accurately estimating losses.

[0067] The relationship between the grid connection point power and the actual PCS output is:

[0068] y=x+x1

[0069] Where:

[0070] x is the actual output of PCS, in kW, x1 is the loss within the station, such as transformer loss, station variable load, etc. This value varies under different working conditions and has a certain degree of randomness, in kW, and y is the power of the grid connection point, in kW.

[0071] When recording valid data, a data recording protection mechanism is set. The data recording protection mechanism is some data protection methods optimized and summarized during the use of the embodiments of the present invention. The use of these methods can effectively improve the stability and applicability of the function.

[0072] (1) New data priority mechanism

[0073] After accumulating experience from multiple projects, we found that due to the influence of factors such as on-site temperature and power fluctuations of station transformers, the losses within the station have a certain timeliness, which leads to a reduction in the reference value of some premature parameters in the data records. Still using premature data may reduce the accuracy of power prediction.

[0074] Therefore, when updating the data of the current interval, it is necessary to determine whether the absolute value of the difference between the data of the adjacent interval and the data of the current interval is less than the set threshold. If it is less than the set threshold, the data of the adjacent interval can be directly cleared or invalidated, and the new data can be entered into the current interval. That is to say, when the data of the adjacent interval is close to the data of the current interval, the data of the adjacent interval is cleared, and the data of the current interval will be used first in calculations. The adjacent interval is in an invalid state and is ready to receive new data at any time to ensure the timeliness of the data.

[0075] In a preferred but non-limiting embodiment of the present invention, the threshold is set to an absolute value of the power difference between the grid connection points that is less than 0.01Pn.

[0076] (2) Mechanism to eliminate zero drift data

[0077] When the PCS is completely at zero power, the station loss does not disappear, but is in a very low load state. In this state, the current is too small and lower than the precise sampling interval of the sampling module, resulting in large fluctuations in the collected power and no reference value. Shielding data within a set value range can effectively avoid interference of zero drift data on data recording.

[0078] In a preferred but non-limiting embodiment of the present invention, shielding data in the range of +-5% Pn can effectively avoid interference of zero-drift data on data recording.

[0079] (3) Full-fill / discharge processing mechanism, data isolation of adjacent intervals

[0080] When the energy storage power station is fully charged and discharged, the power at the grid connection point will drop linearly. If new data is given priority blindly, all data records will be cleared or only individual data will remain, which will seriously affect the efficiency of data record updates.

[0081] Therefore, it is necessary to add some data judgment to avoid the problem of data records being cleared during power reduction, such as Figure 5 and Figure 6 As shown, in the embodiment of the present invention, a mechanism for opening and closing intervals of data recording is added. In the discharge range, if the absolute value of the data difference between the interval where the new data is located and the data of the larger interval is less than the set threshold, the new data is not recorded; if the absolute value of the data difference between the interval where the new data is located and the data of the smaller interval is less than the set threshold, then according to the new data priority principle, the data of the smaller interval is cleared and the new data is recorded. In the charging range, on the contrary, if the absolute value of the data difference between the interval where the new data is located and the data of the smaller interval is less than the set threshold, the new data is not recorded. If the absolute value of the data difference between the interval where the new data is located and the data of the larger interval is less than the set threshold, the data of the larger interval is cleared and the new data is recorded.

[0082] Each interval has only one set of data. Only when the data of two adjacent intervals is less than the threshold, that is, the two data are in the special boundary area of ​​their respective intervals, will the judgment of data isolation be made.

[0083] In a preferred but non-limiting embodiment of the present invention, the data whose absolute value of the grid-connected point power difference is less than 0.01Pn is generally taken as approximate data. When Pn is 100000 kW, 0.01Pn is 1000 kW.

[0084] For example:

[0085] Table 3 When Pn is 100000kw, please refer to the data table for details of two adjacent intervals

[0086]

[0087] In the discharge range, when the new data is:

[0088] When the grid-connected power is 39575kW and the actual output is 40200kW,

[0089] Since the grid-connected power of 39575kW is within the range of 40000kW to 30000kW, 40000kW is 0.4Pn, and 30000kW is 0.3Pn, the grid-connected power of 39575kw belongs to the interval: 0.4Pn to 0.3Pn;

[0090] The power difference between the new data and the larger interval data is: the larger interval grid connection point power minus the new data grid connection point power, that is, 40268kW-39575kW=693kW;

[0091] Since the difference of 693kW between the grid connection point power of the new data and the grid connection point power of the larger interval is less than 1000kW, that is, less than 0.01Pn, the new data is close to the data of the larger interval;

[0092] According to the full-fill-discharge situation processing set by the present invention, the mechanism of isolating the data of the adjacent intervals, since the new data is close to the data of the larger interval, the new data is no longer recorded.

[0093] Step 3: Based on the output comparison table established in step 2, estimate the actual output and loss of the PCS required for the theoretical power;

[0094] During a frequency modulation operation, new theoretical power will be continuously generated, and the cooperative control device will estimate the actual output of the PCS in real time through its own recorded output comparison table.

[0095] The PCS actual output estimation process is to first exclude the data with 0, select the two valid records closest to the theoretical power in the output comparison table, and calculate the required PCS actual output through the two-point interpolation method. If all the records are 0 or there are less than two valid records, the output is directly based on the PCS theoretical power. At the same time, the data will be refreshed in the output comparison table in real time, which can be used as the data basis for the next similar action process, realizing a similar self-learning ability.

[0096] Substituting the interpolation formula into the required PCS actual output can be obtained. The difference between the actual PCS output required by the theoretical power and the theoretical power is the calculated loss.

[0097] Two-point interpolation formula:

[0098]

[0099] Where:

[0100] x is the theoretical power, i.e. the target power at the grid connection point, in kW;

[0101] x1 is the grid-connected power of the first group of valid data that is closer to the theoretical power in the output comparison table, in kW;

[0102] y1 is the actual output of the first group of valid data that is closest to the theoretical power in the output comparison table, in kW;

[0103] x2 is the grid-connected power of the second group of valid data in the output comparison table that is closer to the theoretical power, in kW;

[0104] y2 is the actual output of the second group of valid data in the output comparison table that is closer to the theoretical power, in kW;

[0105] y is the actual output of the PCS required by the theoretical power, in kW.

[0106] In a preferred but non-limiting embodiment of the present invention, Figure 4 As shown, the specific reference data selected by the theoretical power of 10000kw is shown in Table 4 below:

[0107] Table 4 Specific reference data table selected when the theoretical power is 10000kw

[0108] Serial number Grid connection point power / kW Actual output / kW 1 4433 5000 2 16385 16500

[0109] According to the two-point interpolation formula, the actual output of the PCS required to achieve the theoretical power of 10,000 kW is calculated. The specific calculation process is as follows:

[0110]

[0111] It can be seen from the above calculation that, in the two sets of data, the change in the order of the data does not affect the final calculated PCS actual output value. In this embodiment, when the theoretical power is 10000 kW, the required PCS actual output value is 10356.4675 kW.

[0112] Step 4: Based on the actual PCS output and loss required by the theoretical power estimated in step 3, each PCS is assigned to execute and the grid connection point power is controlled to the grid connection point target power position.

[0113] The embodiment of the present invention further provides a loss calculation system, which executes the above-mentioned loss calculation method for improving the control accuracy of primary frequency regulation of energy storage cooperative control, including:

[0114] Collection and verification module, output comparison module, PCS actual output and loss estimation module and PCS execution module;

[0115] The acquisition and verification module is used to collect and verify the grid-connected point power and the actual output data of the PCS;

[0116] The output comparison module is used to record the valid data collected by the acquisition and verification module and establish an output comparison table;

[0117] The PCS actual output and loss estimation module is used to estimate the PCS actual output and loss required by the theoretical power;

[0118] The PCS execution module is used to allocate each PCS execution and control the grid connection point power to the grid connection point target power position.

[0119] The present disclosure may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0120] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0121] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in the computer-readable storage medium in each computing / processing device.

[0122] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed completely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control, characterized in that: include: Step 1: Collect and verify the grid connection point power and PCS actual output data; Step 2: Based on the data in step 1, record the valid data and establish an output comparison table; Step 3: Based on the output comparison table established in step 2, estimate the actual output and loss of the PCS required for the theoretical power; Step 4: Based on the actual PCS output and loss required by the theoretical power estimated in step 3, each PCS is assigned to execute and the grid connection point power is controlled to the grid connection point target power position.

2. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 1 is characterized in that: In step 1, verifying the grid connection point power and the actual output data of the PCS includes: checking whether a sign error occurs, and whether the grid connection point power is higher than the actual output of the PCS; The correct signs are: negative for charging and positive for discharging.

3. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 1 is characterized in that: In step 2, the grid connection point power is divided into intervals to record the grid connection point power and PCS actual output data in each interval.

4. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 3 is characterized in that: In step 2, when recording valid data, a data recording protection mechanism is set, and the data recording protection mechanism includes a new data priority mechanism, a zero-drift data exclusion mechanism, and a full-fill-discharge situation processing mechanism.

5. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 4 is characterized in that: The new data priority mechanism is: When updating the data of the current interval, determine whether the absolute value of the difference between the data of the adjacent interval and the data of the current interval is less than the set threshold. If it is less than the set threshold, directly clear the data of the adjacent interval and enter the new data into the current interval.

6. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 4 is characterized in that: The mechanism to exclude zero drift data is: When the PCS is completely at zero power, the data in the set value range is shielded.

7. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 4 is characterized in that: The full filling and discharging situation handling mechanism is: When the energy storage power station is fully charged and discharged, a data recording opening and closing interval mechanism is added. Within the discharge range, if the absolute value of the difference between the interval where the new data is located and the data in the larger interval is less than the set threshold, the new data will not be recorded; if the absolute value of the difference between the interval where the new data is located and the data in the smaller interval is less than the set threshold, then according to the new data priority principle, the data in the smaller interval will be cleared and the new data will be recorded; Within the charging range, contrary to the discharging range, if the absolute value of the difference between the interval where the new data is located and the data in the smaller interval is less than the set threshold, the new data will not be recorded. If the absolute value of the difference between the interval where the new data is located and the data in the larger interval is less than the set threshold, the data in the larger interval will be cleared and the new data will be recorded.

8. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 1 is characterized in that: In step 3, the calculation process of the actual PCS output required for the theoretical power is: Exclude the data that is 0, select the two valid records closest to the theoretical power in the output comparison table, and calculate the required PCS actual output through the two-point interpolation method; if all the records are 0 or there are less than two valid records, directly use the PCS theoretical power for output, and refresh the data to the processing comparison table in real time; The two-point interpolation formula is: Where: x is the theoretical power; x1 is the grid-connected power of the first group of valid data in the output comparison table that is closer to the theoretical power; y1 is the actual output of the first group of valid data in the output comparison table that is closer to the theoretical power; x2 is the grid-connected power of the second group of valid data in the output comparison table that is closer to the theoretical power; y2 is the actual output of the second group of valid data in the output comparison table that is closer to the theoretical power; y is the actual output of the PCS required for the theoretical power.

9. The loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control according to claim 8 is characterized in that: In step 3, the loss is the difference between the actual output of the PCS required by the theoretical power and the theoretical power.

10. A loss calculation system, executing the loss calculation method for improving the control accuracy of primary frequency modulation of energy storage cooperative control as described in any one of claims 1 to 9, characterized in that: include: Collection and verification module, output comparison module, PCS actual output and loss estimation module and PCS execution module; The acquisition and verification module is used to collect and verify the grid-connected point power and the actual output data of the PCS; The output comparison module is used to record the valid data collected by the acquisition and verification module and establish an output comparison table; The PCS actual output and loss estimation module is used to estimate the PCS actual output and loss required by the theoretical power; The PCS execution module is used to allocate each PCS execution and control the grid connection point power to the grid connection point target power position.

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