A high-voltage direct-hanging energy storage system inductance value calculation method and system

Abstract

The application relates to a high-voltage direct-hanging energy storage system inductance value calculation method and system, which comprises the following steps: collecting the equivalent resistance, system frequency, control period, fundamental current and angular frequency of different harmonics of a high-voltage direct-hanging energy storage system; determining a desired performance index; considering error influencing factors during operation of the high-voltage direct-hanging energy storage system, introducing an experience coefficient to correct deviation; the error influencing factors include: control response speed, control accuracy, harmonic quality experience coefficient and reactive power output capacity; according to different requirements of the high-voltage direct-hanging energy storage system operation, introducing a weight coefficient to balance the performance of the high-voltage direct-hanging energy storage system, and calculating the inductance value of the high-voltage direct-hanging energy storage system according to the experience coefficient and the weight coefficient.

Description

Technical Field

[0001] This application relates to the field of inductance calculation technology for energy storage systems, and more specifically, to a method and system for calculating the inductance value of a high-voltage direct-connected energy storage system. Background Technology

[0002] In high-voltage direct-connected energy storage systems, inductance is a critical parameter, closely related to many system performance characteristics. A larger inductance improves control accuracy and harmonic quality, but reduces control response speed and limits reactive power output. Conversely, a smaller inductance speeds up control response and increases the upper limit of reactive power output, but negatively impacts control accuracy and harmonic quality.

[0003] Existing technologies often struggle to accurately balance the requirements of power output, control response speed and accuracy, and harmonic quality when determining the inductance value of high-voltage direct-connected energy storage systems. Finding a suitable method for calculating reactance values ​​to achieve a balanced optimization of system performance has become a pressing technical challenge.

[0004] Existing technology, such as Chinese patent application publication number "CN116644661A", discloses a design method for a high energy density inductor. The method includes: obtaining the value ranges corresponding to the size information and calculation information of the inductor coil; wherein, the size information includes at least: number of turns, number of layers, inner diameter of the coil, height of a single turn, width of a single turn, distance between turns, and distance between layers, and the calculation information includes at least: turn voltage, current density, and resistance; and optimizing within the value range according to the calculation formulas for coil current, coil resistance, coil inductance, and energy density to determine the specific size information corresponding to the maximum energy density that satisfies the value range.

[0005] The problem with the existing technology is that the method mainly focuses on determining the specific size information that meets the maximum energy storage density by optimizing within the range of values ​​based on the size information and calculation information of the inductor coil, without fully considering the system operation performance factors and lacking consideration of the dynamic operation of the system. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a method and system for calculating the inductance value of a high-voltage direct-connected energy storage system.

[0007] The technical solution of this invention is as follows:

[0008] This invention proposes a method for calculating the inductance value of a high-voltage direct-connected energy storage system, comprising the following steps:

[0009] Step S1: Collect the equivalent resistance R, system frequency f, and control cycle of the high-voltage direct-connected energy storage system. Fundamental current and the angular frequencies of different harmonics And determine the expected performance indicators;

[0010] Step S2: Considering the error factors affecting the operation of the high-voltage direct-connected energy storage system, an empirical coefficient is introduced to correct the deviation. The error factors include: control response speed, control accuracy, harmonic quality empirical coefficient, and reactive power output capability.

[0011] Step S3: Based on the different operational requirements of the high-voltage direct-connected energy storage system, a weighting coefficient is introduced to balance the performance of the high-voltage direct-connected energy storage system, and the inductance value of the high-voltage direct-connected energy storage system is calculated based on the empirical coefficient and the weighting coefficient.

[0012] In a preferred embodiment, the desired performance metric includes: the desired control response time. Expected control accuracy error range Expected total harmonic distortion and expected reactive power output capability and the rated reactive power of the converter .

[0013] As a preferred embodiment, considering the error factors affecting the operation of the high-voltage direct-connected energy storage system, an empirical coefficient is introduced to correct the deviation; for the control response speed deviation, an empirical coefficient for control response speed is introduced to correct the deviation, and the specific formula is as follows:

[0014] ;

[0015] In the formula: To achieve the desired control response time; The empirical coefficient is used to control the response speed; R is the equivalent resistance.

[0016] As a preferred embodiment, considering the error factors affecting the operation of the high-voltage direct-connected energy storage system, an empirical coefficient is introduced to correct the deviation; for the control accuracy deviation, an empirical coefficient for control accuracy is introduced to correct the deviation, and the specific formula is as follows:

[0017] ;

[0018] In the formula: Empirical coefficients for controlling accuracy; For a given voltage ripple; The desired control accuracy error range; To control the cycle.

[0019] As a preferred embodiment, considering the error factors affecting the operation of the high-voltage direct-connected energy storage system, an empirical coefficient is introduced to correct the deviation; for harmonic quality deviation, an empirical harmonic quality coefficient is introduced to correct the deviation, and the specific formula is as follows:

[0020] ;

[0021] In the formula: These are empirical coefficients for harmonic quality. The fundamental angular frequency; denoted as the desired total harmonic distortion rate.

[0022] As a preferred embodiment, considering the error factors affecting the operation of the high-voltage direct-connected energy storage system, an empirical coefficient is introduced to correct the deviation; for the reactive power output capacity deviation, an empirical coefficient for reactive power output capacity is introduced to correct the deviation, and the specific formula is as follows:

[0023] ;

[0024] In the formula: Empirical coefficient for reactive power output capability; Q is the rated reactive power of the converter; I is the desired reactive power output value; and I is the operating current flowing through the converter.

[0025] In a preferred embodiment, the inductance value of the high-voltage direct-connected energy storage system is calculated based on empirical coefficients and weighting coefficients. The formula for calculating the inductance value is as follows:

[0026] ;

[0027] In the formula: a, b, c, and d are the weighting coefficients for control response speed, control accuracy, harmonic quality, and reactive power output capability, respectively. .

[0028] On the other hand, the present invention also provides a system for calculating the inductance value of a high-voltage direct-connected energy storage system, comprising:

[0029] The data acquisition and performance index determination module collects the equivalent resistance R, system frequency f, and control cycle of the high-voltage direct-connected energy storage system. Fundamental current and the angular frequencies of different harmonics And determine the expected performance indicators;

[0030] The deviation correction module considers the error factors affecting the operation of the high-voltage direct-connected energy storage system and introduces empirical coefficients to correct the deviation. The error factors include: control response speed, control accuracy, harmonic quality empirical coefficient, and reactive power output capability.

[0031] The weighting and inductance calculation module introduces weighting coefficients to balance the performance of high-voltage direct-connected energy storage systems based on different operational requirements. It calculates the inductance value of the high-voltage direct-connected energy storage system based on empirical coefficients and weighting coefficients.

[0032] In another aspect, the present invention also provides an electronic device having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements a method for calculating the inductance value of a high-voltage direct-connected energy storage system as described in any embodiment of the present invention.

[0033] In another aspect, the present invention also provides a computer-readable medium for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement a method for calculating the inductance value of a high-voltage direct-connected energy storage system as described in any embodiment of the present invention.

[0034] This invention offers the following advantages: By collecting parameters such as the equivalent resistance, system frequency, control cycle, fundamental current, and angular frequencies of different harmonics of the high-voltage direct-connected energy storage system, and determining desired performance indicators such as control response time, control accuracy error range, total harmonic distortion rate, and reactive power output capability, the key factors for system operation are comprehensively considered. Empirical coefficients are introduced to correct for errors affecting control response speed, control accuracy, harmonic quality, and reactive power output capability. Furthermore, weighting coefficients are set according to different system operation requirements, balancing various performance aspects of the high-voltage direct-connected energy storage system, thereby more accurately calculating the inductance value. This effectively solves the problem that existing technologies struggle to simultaneously meet multiple system performance requirements. The introduction of empirical and weighting coefficients makes the inductance calculation method of this invention more flexible and adaptable, applicable to various inductance value calculation scenarios for high-voltage direct-connected energy storage systems. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the method flow of the present invention;

[0037] Figure 2 This is a topology diagram of a high-voltage direct-connected energy storage system. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be understood that the step numbers used in the text are for ease of description only and are not intended to limit the order in which the steps are performed.

[0040] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0041] The terms “comprising” and “including” indicate the presence of the described feature, whole, step, operation, element and / or component, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0042] The term “and / or” refers to any combination of one or more of the associated listed items, as well as all possible combinations, and includes these combinations.

[0043] Example 1:

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, specific embodiments of this application will be described below, with reference to the accompanying drawings. Figure 1 The technical solution of the present invention will be clearly and completely described.

[0045] To address the problems in the existing technology, this invention provides a method for calculating the inductance value of a high-voltage direct-connected energy storage system, comprising the following steps:

[0046] Step S1: Collect the equivalent resistance R, system frequency f, and control cycle of the high-voltage direct-connected energy storage system. Fundamental current and the angular frequencies of different harmonics And determine the expected performance indicators, including: expected control response time. Expected control accuracy error range Expected total harmonic distortion and expected reactive power output capability and the rated reactive power of the converter .

[0047] Step S2: Considering the error factors affecting the operation of the high-voltage direct-connected energy storage system, an empirical coefficient is introduced to correct the deviation. These error factors include: control response speed, control accuracy, harmonic quality empirical coefficient, and reactive power output capability. Among them:

[0048] Consider controlling the response speed:

[0049] The control response speed is related to the system's time constant. For circuits containing inductors, the time constant is... To meet the desired control response time We can obtain the formula for calculating the deviation correction by introducing the empirical coefficient of control response speed:

[0050] ;

[0051] In the formula: It is an empirical coefficient for controlling response speed, and its value ranges from... The value is determined based on the specific characteristics of the system and is used to correct the deviation between the actual and ideal models; L is the bridge arm inductance value; R is the equivalent resistance. The result can be derived as follows:

[0052] .

[0053] Considering control accuracy:

[0054] According to Kirchhoff's laws and the law of electromagnetic induction, in an inductive circuit, the rate of change of current is related to the inductance value, that is... For the desired control accuracy error range and given voltage ripple The formula for calculating the deviation correction by introducing the empirical coefficient of control accuracy can be derived as follows:

[0055] ;

[0056] In the formula: To control the cycle, It is an empirical coefficient for controlling accuracy, and its value ranges from... It is determined based on system characteristics and control strategy.

[0057] Considering harmonic quality:

[0058] In AC circuits, inductors suppress harmonic currents. According to harmonic analysis theory, harmonic currents... The relationship with inductance is as follows:

[0059] ;

[0060] In the formula: For fundamental current, Let be the harmonic angular frequency. To ensure the total harmonic distortion meets the desired value, it can be calculated using the following formula:

[0061] ;

[0062] In the formula: The desired total harmonic distortion (THD) is given by . It is the sum of the squares of the effective values ​​of the current (or voltage) from the second harmonic to the infiniteth harmonic;

[0063] The relationship with inductance is quite complex, and this method generally introduces a coefficient. The approximate relationship between the two is obtained as follows:

[0064] ;

[0065] In the formula: It is a coefficient related to the harmonic order and system characteristics, and is determined based on the harmonic spectrum characteristics of the system.

[0066] Considering reactive power output capability

[0067] Reactive power of high-voltage direct connection system X is the reactance; to achieve the desired reactive power output capability, we can obtain:

[0068] ;

[0069] In the formula: It is a coefficient related to the reactive power regulation characteristics of the system, and its value ranges from... .

[0070] Step S3: Based on the different operational requirements of the high-voltage direct-connected energy storage system, a weighting coefficient is introduced to balance the performance of the high-voltage direct-connected energy storage system, and the inductance value of the high-voltage direct-connected energy storage system is calculated based on the empirical coefficient and the weighting coefficient.

[0071] Based on the above four aspects, a weighting coefficient is introduced. , , and (satisfy ), final bridge arm inductance value The calculation formula is:

[0072] ;

[0073] In the formula: a, b, c, and d are the weighting coefficients for control response speed, control accuracy, harmonic quality, and reactive power output capability, respectively. .

[0074] like Figure 2As shown: The following is a specific calculation case, assuming a high-voltage direct-connected energy storage system has the following parameters:

[0075] System frequency ,but .

[0076] Equivalent resistance .

[0077] Control cycle .

[0078] Expected control response time .

[0079] Expected control accuracy error range .

[0080] Desired total harmonic distortion .

[0081] Rated reactive power of converter reactive power demand Assuming the fundamental current .

[0082] Based on system characteristics, take empirical coefficients. , , , And assuming that in order to balance system performance, the weighting coefficients are taken as follows: , , , .

[0083] Substitute the above data into the formula to calculate the bridge arm inductance value. :

[0084] ;

[0085] Example 2:

[0086] This embodiment provides a system for calculating the inductance value of a high-voltage direct-connected energy storage system, including:

[0087] The data acquisition and performance index determination module collects the equivalent resistance R, system frequency f, and control cycle of the high-voltage direct-connected energy storage system. Fundamental current and the angular frequencies of different harmonics And determine the expected performance indicators;

[0088] The deviation correction module considers the error factors affecting the operation of the high-voltage direct-connected energy storage system and introduces empirical coefficients to correct the deviation. The error factors include: control response speed, control accuracy, harmonic quality empirical coefficient, and reactive power output capability.

[0089] The weighting and inductance calculation module introduces weighting coefficients to balance the performance of high-voltage direct-connected energy storage systems based on different operational requirements. It calculates the inductance value of the high-voltage direct-connected energy storage system based on empirical coefficients and weighting coefficients.

[0090] Example 3:

[0091] This embodiment provides an electronic device that stores a computer program. When the computer program is executed by a processor, it implements a method for calculating the inductance value of a high-voltage direct-connected energy storage system as described in any embodiment of the present invention.

[0092] Example 4:

[0093] This embodiment provides a computer-readable medium for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement a method for calculating the inductance value of a high-voltage direct-connected energy storage system as described in any embodiment of the present invention.

[0094] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, A and B simultaneously, or B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, at least one of a, b, and c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.

[0095] Those skilled in the art will recognize that the units and algorithm steps described in the embodiments disclosed herein can be implemented using electronic hardware, computer software, or a combination of electronic hardware and software. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0096] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0097] In the several embodiments provided in this application, any function, if implemented as a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0098] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for calculating the inductance value of a high-voltage direct-connected energy storage system, characterized in that, Includes the following steps: Step S1: Collect the equivalent resistance R, system frequency f, and control cycle of the high-voltage direct-connected energy storage system. Fundamental current and the angular frequencies of different harmonics And determine the expected performance indicators; Step S2: Considering the error factors affecting the operation of the high-voltage direct-connected energy storage system, an empirical coefficient is introduced to correct the deviation. Factors affecting error include: control response speed, control accuracy, empirical harmonic quality coefficient, and reactive power output capability; among which: To correct the deviation in control response speed, an empirical coefficient for control response speed is introduced, and the specific formula is as follows: ； In the formula: To achieve the desired control response time; An empirical coefficient for controlling response speed; R is the equivalent resistance; To correct the control accuracy deviation, an empirical coefficient for control accuracy is introduced, and the specific formula is as follows: ； In the formula: Empirical coefficients for controlling accuracy; For a given voltage ripple; The desired control accuracy error range; To control the cycle; To correct harmonic quality deviation, an empirical harmonic quality coefficient is introduced, and the specific formula is as follows: ； In the formula: These are empirical coefficients for harmonic quality. The fundamental angular frequency; The desired total harmonic distortion (THD) is given by denoted as . To correct the deviation in reactive power output capability, an empirical coefficient for reactive power output capability is introduced. The specific formula is as follows: ； In the formula: Empirical coefficient for reactive power output capability; Q is the rated reactive power of the converter; I is the desired reactive power output value; and I is the operating current flowing through the converter. Step S3: Based on the different operational requirements of the high-voltage direct-connected energy storage system, a weighting coefficient is introduced to balance the performance of the high-voltage direct-connected energy storage system, and the inductance value of the high-voltage direct-connected energy storage system is calculated based on the empirical coefficient and the weighting coefficient. The inductance value of the high-voltage direct-connected energy storage system is calculated based on empirical coefficients and weighting coefficients. The formula for calculating the inductance value is as follows: ； In the formula: a, b, c, and d are the weighting coefficients for control response speed, control accuracy, harmonic quality, and reactive power output capability, respectively. .

2. A system for calculating the inductance value of a high-voltage direct-connected energy storage system as described in claim 1, characterized in that, include: The data acquisition and performance index determination module collects the equivalent resistance R, system frequency f, and control cycle of the high-voltage direct-connected energy storage system. Fundamental current and the angular frequencies of different harmonics And determine the expected performance indicators; The deviation correction module considers the error factors affecting the operation of the high-voltage direct-connected energy storage system and introduces empirical coefficients to correct the deviation. Factors affecting error include: control response speed, control accuracy, harmonic quality empirical coefficient, and reactive power output capability; The weight confirmation and inductance calculation module introduces weighting coefficients to balance the performance of high-voltage direct-connected energy storage systems based on different operational requirements. It calculates the inductance value of the high-voltage direct-connected energy storage system based on empirical coefficients and weighting coefficients.

3. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the inductance value calculation method for a high-voltage direct-connected energy storage system as described in claim 1.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the inductance value calculation method for a high-voltage direct-connected energy storage system as described in claim 1.

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