Power decoupling method based on switch multiplexing type multi-resonant switched capacitor converter

Abstract

The invention provides a power decoupling method based on a switch multiplexing type multi-resonant switched capacitor converter. The method comprises the following steps: establishing a relation model of battery side power and battery side current; establishing a coupling relation matrix from the battery side current to the resonance current; establishing a mapping relation between the resonance current and the absolute phase shift ratio; constructing a coupling matrix of the battery side power and the absolute phase shift; extracting a diagonal matrix from the coupling matrix of the battery side power and the absolute phase shift, and constructing a relational expression of a new output variable and a relational expression of a new input variable after decoupling control according to the diagonal matrix; and determining a new target output vector due value, a new input variable due value and an original input variable due value according to the original target output vector value, the relational expression of the new output variables and the relational expression of the new input variables. According to the invention, power decoupling of multiple coupling loops is realized, mutual interference is prevented, control precision and dynamic response performance are improved, and equalization control of battery energy storage is realized.

Description

Technical Field

[0001] This application relates to the field of power decoupling equalization control technology, and more specifically, to a power decoupling method based on a switch-multiplexed multi-resonant switched-capacitor converter. Background Technology

[0002] Currently, the world faces challenges such as a shortage of traditional fossil fuels and global warming. Developing a new power system primarily based on renewable energy is a crucial measure for the international community to promote a green energy transition. Given the significant volatility and intermittency of renewable energy sources like wind and solar power, energy storage systems, as a flexible regulation resource for power systems, play a vital role in new power systems incorporating a high proportion of renewable energy. Among these, electrochemical energy storage systems, represented by battery storage, often employ a multi-cell series connection to form high-voltage battery clusters to meet power and voltage level requirements. During the use of series-connected battery clusters, inconsistencies between individual cells can negatively impact battery performance and lifespan; therefore, series-connected battery balancing technology is of great importance.

[0003] Currently, capacitive equalization control methods are simple, but they are prone to large peak currents in the circuit. Moreover, they can only achieve voltage equalization and cannot achieve state of charge (SOC) equalization, resulting in incomplete equalization.

[0004] Inductive topologies and some non-resonant inductor-capacitor topologies can achieve not only voltage balancing but also state of charge (SOC) balancing. Inductors can also buffer large peak currents in the circuit. However, these topologies generally use large-volume inductor components, which makes the battery balancing configuration bulky and can cause serious electromagnetic interference (EMI).

[0005] The resonant switched capacitor converter (RSCC) topology adds an inductor to the switched capacitor balanced topology, which can reduce current spikes while maintaining high power density.

[0006] Figure 2 This is a schematic diagram illustrating the structure of a conventional switch-multiplexed multiresonant switched-capacitor converter according to an exemplary embodiment. (Refer to...) Figure 2As shown, a conventional multi-resonant switched-capacitor converter (SMX-MRSCC) structure is presented. This structure uses a half-bridge connected in parallel between each battery cell, enabling power transfer between adjacent cells. n battery cells require n half-bridge modules, totaling 2n switching devices: n-1 Lr and n-1 Cr. However, due to the multi-resonant loop coupling characteristics in the multi-resonant switched-capacitor converter, existing control strategies suffer from problems such as single-control and decoupling difficulties, affecting the speed and efficiency of battery equalization.

[0007] As mentioned in the literature, AF Moghaddam et al. proposed "A Cell Equalization Method Based on Resonant Switched Capacitor Balancing for Lithium-Ion Batteries" (International Conference on Mechanical and Aerospace Engineering, 2018). This method uses multiple pairs of synchronous complementary square waves for control, which means that energy can only be transferred strictly according to the voltage difference between adjacent cells. It cannot achieve flexible energy dispatching across individual cells. In scenarios where there are large inconsistencies between cells within a battery cluster, this restricted transfer path will prolong the equalization time and reduce the overall equalization efficiency. Furthermore, the adaptable adjustment dimensions are limited, making it difficult to cope with the coupling problem between multi-resonant circuits in multi-resonant switched capacitor converters. Circuit coupling directly affects the flexibility of energy transfer, thus restricting the speed and efficiency of battery equalization.

[0008] Therefore, how to achieve series battery balancing and efficient decoupling control of multi-resonant switched capacitor converters, and improve the speed and efficiency of series battery balancing, is an important problem that needs to be solved. Summary of the Invention

[0009] To address one of the shortcomings in the existing technology, the purpose of this application is to provide a power decoupling method based on a switch-multiplexed multi-resonant switched-capacitor converter.

[0010] A first aspect of this application provides a power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter, comprising: Establish a model relating battery-side power to battery-side current; Establish the coupling relationship matrix between the battery-side current and the resonant current; Establish the mapping relationship between the resonant current and the absolute phase shift under phase-shift control; Based on the relationship model between the battery-side power and the battery-side current, the coupling relationship matrix between the battery-side current and the resonant current, and the mapping relationship between the resonant current and the absolute shift ratio, a coupling matrix between the battery-side power and the absolute shift ratio is constructed. Extract the diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and establish the relationship between the new output variable and the new input variable after decoupling control; Based on the original target output vector value, the relationship between the new output variables, and the relationship between the new input variables, open-loop control is used to determine the values ​​that the new target output vector should have, the values ​​that the new input variables should have, and the values ​​that the original input variables should have.

[0011] Optionally, establishing the coupling relationship matrix from the battery-side current to the resonant current includes: Establish the relationship matrix between the resonant current and the AC port current of the half-bridge; Establish the relationship matrix between the AC port current and the DC port current of the half-bridge; Establish a matrix relating the DC port current of the half-bridge to the battery-side current; Based on the relationship matrix between the resonant current and the half-bridge AC port current, the relationship matrix between the half-bridge AC port current and the half-bridge DC port current, and the relationship matrix between the half-bridge DC port current and the battery-side current, the coupling relationship between the battery-side current and the resonant current is determined.

[0012] Optionally, the relationship matrix between the resonant current and the half-bridge AC port current is: H 1: i k =H 1 ·i r in, i k This represents the AC port current of the half-bridge. i r This represents the resonant current. H 1 represents the matrix relating the resonant current to the AC port current of the half-bridge; The relationship matrix between the AC port current and the DC port current of the half-bridge H 2 is represented as: i m =H 2· i k in, i mThis represents the DC port current of the half-bridge. i k This represents the AC port current of the half-bridge. H 2 represents the relationship matrix between the AC port current and the DC port current of the half-bridge; The relationship matrix between the DC port current of the half-bridge and the battery-side current H 3 is represented as: i b =H 3· i m in, i b This indicates the battery-side current. i m This represents the DC port current of the half-bridge. H 3 represents the matrix relating the DC port current of the half-bridge to the battery-side current; The coupling relationship between the battery-side current and the resonant current is as follows: i b =H 1 H 2 H 3· i r in, i b This indicates the battery-side current. H 1 represents the matrix relating the resonant current to the AC port current of the half-bridge. H 2 represents the matrix showing the relationship between the AC port current and the DC port current of the half-bridge. H 3 represents the matrix showing the relationship between the DC port current of the half-bridge and the battery-side current. i r This represents the resonant current.

[0013] Optionally, the relationship model between the battery-side power and the battery-side current is as follows: P = U · i b in, P This indicates the battery-side power. U Represents the voltage vector. i b This indicates the battery-side current.

[0014] Optionally, the mapping relationship between the resonant current and the absolute phase shift under the phase shift control is as follows: ; ; in, i r This represents the resonant current. U Represents the voltage vector. Indicates the characteristic impedance of the resonant cavity. D Compared to the absolute shift, Indicates resonant inductance. Indicates the resonant capacitance; The coupling matrix between the battery-side power and the absolute shift H PD for: P=H PD · D in, P This indicates the battery-side power. H PD The coupling matrix represents the ratio of the battery-side power to the absolute shift. D This indicates the absolute shift ratio.

[0015] Optionally, the step of extracting a diagonal matrix from the coupling matrix comparing the battery-side power with the absolute shift, and constructing a new relationship between the output variables and the input variables after decoupling control based on the diagonal matrix, includes: Extract the diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and multiply both sides of the equation of the diagonal matrix by the inverse of the remaining matrix to determine the relationship between the new output variable and the new input variable after decoupling control. The relationship between the new output variables after decoupling control is as follows: Y'=H 4 -1 P ; in, Y’ This represents the new target output vector. P This represents the original target output vector. H 4 -1 This represents the first transformation matrix; The relational expression for the new input variables is: X'=H 5 D in, X’ This represents the new input variable. H 5 represents the second transformation matrix.D This represents the original input variables.

[0016] Optionally, the step of determining the required values ​​of the new target output vector, the new input variables, and the original input variables using open-loop control based on the original target output vector value, the relationship between the new output variables, and the relationship between the new input variables includes: The original target output vector value is input into the relational expression of the new output variable after decoupling control to determine the value that the new target output vector should have. Based on the expected value of the new target output vector, the expected value of the new input variable is determined through open-loop control; Based on the expected values ​​of the new input variables and the relationship between the new input variables, the expected values ​​of the original input variables are determined using the second transformation matrix.

[0017] A second aspect of this application provides a power decoupling system based on a switch-multiplexed multiresonant switched-capacitor converter, comprising: The first module is used to establish a model of the relationship between battery-side power and battery-side current. The second module is used to establish the coupling relationship matrix from the battery-side current to the resonant current; The third module is used to establish the mapping relationship between the resonant current and the absolute phase shift under phase shift control; The coupling relationship determination module is used to construct the coupling matrix between the battery-side power and the absolute shift ratio based on the relationship model between the battery-side power and the battery-side current, the coupling relationship matrix between the battery-side current and the resonant current, and the mapping relationship between the resonant current and the absolute shift ratio. The first decoupling module is used to extract a diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and to construct a new relationship between the output variables and the input variables after decoupling control based on the diagonal matrix. The second decoupling module is used to determine the values ​​of the new target output vector, the new input variables, and the original input variables through open-loop control, based on the original target output vector value, the relationship between the new output variables, and the relationship between the new input variables.

[0018] A third aspect of this application provides a non-transitory computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps of any of the methods provided in the first aspect of this application.

[0019] A fourth aspect of this application provides an electronic device comprising: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of any of the methods provided in the first aspect of this application.

[0020] This application presents a power decoupling method based on a switch-multiplexed multi-resonant switched-capacitor converter. This method establishes a model relating battery-side power to battery-side current, analyzes the coupling matrix between battery-side current and resonant current, and constructs a coupling matrix between battery-side power and absolute shift ratio by combining the mapping relationship between resonant current and absolute shift ratio. By extracting the diagonal matrix, new relationships between output variables and input variables are constructed, achieving power decoupling. This transforms multi-input multi-output into multiple single-input single-output methods. Combined with open-loop control, it achieves effective decoupling control of each channel, significantly improving control accuracy and dynamic response performance. It also solves the mutual interference problem inherent in traditional control methods and is suitable for the balanced control of battery energy storage systems.

[0021] Other technical effects resulting from the additional features will be further illustrated in the corresponding embodiments. Attached Figure Description

[0022] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a flowchart illustrating a power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to an exemplary embodiment.

[0023] Figure 2 This is a schematic diagram illustrating the structure of a conventional switch-multiplexed multiresonant switched-capacitor converter according to an exemplary embodiment.

[0024] Figure 3 This is a topology diagram of a prototype active balancing system for a 4-cell battery pack series connection, according to an exemplary embodiment.

[0025] Figure 4 This is a schematic diagram of a resonant switched capacitor converter (RSCC) unit topology according to an exemplary embodiment.

[0026] Figure 5 This is a schematic diagram of open-loop control of a switch-multiplexed multiresonant switched-capacitor converter unit according to an exemplary embodiment.

[0027] Figure 6 This is a schematic diagram of closed-loop control of a switch-multiplexed multiresonant switched-capacitor converter unit according to an exemplary embodiment.

[0028] Figure 7This is a schematic diagram of the steady-state battery-side current waveform of a 4-battery prototype after power decoupling control, according to an exemplary embodiment.

[0029] Figure 8 This is a schematic diagram of a power decoupling system based on a switch-multiplexed multi-resonant switched-capacitor converter, according to an exemplary embodiment. Detailed Implementation

[0030] The present application will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application. These all fall within the protection scope of the present application.

[0031] In the description of the embodiments in this application, "multiple" means two or more, unless otherwise explicitly specified. In this application, unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0032] The terms "comprising" and "having," and any variations thereof, in the embodiments of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or devices.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0034] Existing capacitor-based equalization control methods for series-connected batteries are prone to large peak currents and can only achieve voltage equalization, failing to achieve state-of-charge (SOC) equalization, resulting in incomplete equalization. Inductor-based equalization control methods, while achieving both voltage and SOC equalization, employ large inductors in their topologies, leading to bulky battery equalization configurations and significant electromagnetic interference. Existing equalization control methods using resonant switched-capacitor converters suffer from simplistic control strategies, difficulty in decoupling, and negative impacts on battery speed and efficiency. To address these issues, this application provides a power decoupling method based on a switch-multiplexed multi-resonant switched-capacitor converter to resolve these problems.

[0035] Figure 1 This is a flowchart illustrating a power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to an exemplary embodiment.

[0036] Reference Figure 1 As shown in one embodiment of this application, a power decoupling method based on a switch-multiplexed multi-resonant switched-capacitor converter is provided, including S11 to S16.

[0037] S11, Establish a model relating battery-side power to battery-side current.

[0038] S12, establish the coupling relationship matrix from battery-side current to resonant current.

[0039] S13, establish the mapping relationship between the resonant current and the absolute phase shift under phase shift control.

[0040] S14. Based on the relationship model between battery-side power and battery-side current, the coupling relationship matrix between battery-side current and resonant current, and the mapping relationship between resonant current and absolute shift ratio, construct the coupling matrix between battery-side power and absolute shift ratio.

[0041] S15, extract the diagonal matrix from the coupling matrix of battery-side power and absolute displacement, and establish the relationship between the new output variable and the new input variable after decoupling control.

[0042] S16, based on the original target output vector value, the relationship between the new output variables and the relationship between the new input variables, open-loop control is used to determine the required values ​​of the new target output vector, the new input variables, and the original input variables.

[0043] The embodiments described above in this application establish a relationship model between battery-side power and battery-side current, analyze the coupling relationship matrix between battery-side current and resonant current, and construct a coupling matrix between battery-side power and absolute shift ratio by combining the mapping relationship between resonant current and absolute shift ratio. By extracting the diagonal matrix, new relationships between output variables and new relationships between input variables are constructed, thereby achieving power decoupling. This converts multiple inputs and multiple outputs into multiple single inputs and single outputs. Combined with open-loop control, effective decoupling control of each channel is achieved, significantly improving control accuracy and dynamic response performance. This solves the mutual interference problem existing in traditional control methods and is suitable for the balanced control of battery energy storage systems.

[0044] Figure 3 This is a topology diagram of a prototype active balancing system for a 4-cell battery pack series connection, according to an exemplary embodiment.

[0045] Reference Figure 3 As shown, a prototype of a 4-cell series battery cluster active balancing system includes: 4 battery packs, 4 filter capacitors, 4 parallel half-bridge modules and 3 resonant cavities. The filter capacitors are connected in parallel on the DC side of the battery packs, the half-bridge modules are connected in parallel on the DC side of the battery packs, and the resonant cavities are connected to the AC side of the half-bridge modules.

[0046] Specifically, the four battery packs are battery packs B 1. Battery pack B 2. Battery pack B 3. Battery pack B 4. Four battery packs are connected in series to form a battery cluster. The voltages of the four battery packs are respectively... U 1. U 2. U 3. U 4.

[0047] In this embodiment, the rated voltage of the four battery packs is 40V and the rated capacity is 314Ah.

[0048] The four filter capacitors are C1, C2, C3, and C4, each with a capacitance of 10mF.

[0049] Each battery pack is connected in parallel with a filter capacitor, which is used to filter out high-frequency components on the current side.

[0050] Each battery pack is connected in parallel with a half-bridge module, and each half-bridge module includes a pair of half-bridges. B 1. Parallel first half-bridge module, which includes a pair of half-bridges that are switching devices. S 11 Switching devices S 12 Battery pack BThe second half-bridge module is connected in parallel, and its two half-bridges consist of switching devices. S 21 Switching devices S 22 Battery pack B The third half-bridge module is connected in parallel, and its two half-bridges are switching devices. S 31 Switching devices S 32 Battery pack B The fourth half-bridge module is connected in parallel, and it includes a pair of half-bridges that are switching devices. S 41 Switching devices S 42 .

[0051] In this configuration, the upper and lower transistors of each half-bridge module are complementaryly switched on with a 50% duty cycle, and the phase shift time difference between the upper transistors of two adjacent half-bridge modules is [missing information]. D 12 · T s , D 23 · T s , D 34 · T s ,in, D 12 · T s Indicates switching device S 21 Lagging behind switching devices S 11 Phase shift time, D 23 · T s Indicates switching device S 31 Lagging behind switching devices S 21 Phase shift time, D 34 · T s Indicates switching device S 41 Lagging behind switching devices S 31 Phase shift time, D 12 This indicates that the second half-bridge module lags behind the movement of the first half-bridge module. D 23 This indicates that the third half-bridge module lags behind the second half-bridge module in terms of movement. D34 This indicates that the fourth half-bridge module lags behind the third half-bridge module in terms of movement. T s In this embodiment, the switching period is indicated. T s It is 10us.

[0052] The switching functions are as follows: s 11 Indicates switching device S 11 The switching function, (1- s 11 ,) indicates a switching device S 12 The switching function, s 21 Indicates switching device S 21 The switching function, (1- s 21 ) indicates a switching device S 22 The switching function, s 31 Indicates switching device S 31 The switching function, (1- s 31 ) indicates a switching device S 32 The switching function, s 41 Indicates switching device S 41 The switching function, (1- s 41 ) indicates a switching device S 42 The switching function.

[0053] The AC sides of the four half-bridge modules are connected to three resonant cavities. The AC sides of the first and second half-bridge modules are connected to the first resonant cavity, the AC sides of the second and third half-bridge modules are connected to the second resonant cavity, and the AC sides of the third and fourth half-bridge modules are connected to the third resonant cavity. Each resonant cavity includes a resonant inductor. L r and a resonant capacitor C r resonant inductor L r and resonant capacitor C r Series connection. Resonant inductor. L r The inductance value is 20uH, and the resonant capacitor is... C rThe capacitance is 10uF.

[0054] The power decoupling method based on a switch-multiplexed multi-resonant switched-capacitor converter provided in this application can be applied to the above-mentioned prototype of a four-cell series battery cluster active balancing system.

[0055] To construct a model relating battery-side power to battery-side current, in some specific embodiments of this application, for S11, the model relating battery-side power to battery-side current can be established using the following methods: Through battery side current i b With voltage vector U in one switching cycle T s Integrating within the range and dividing by one switching cycle, the battery-side power expression is obtained as follows: in, Indicates battery pack B 1 power, Indicates battery pack B 2 power, Indicates battery pack B 3 power, Indicates battery pack B 4 power, Indicates battery pack B 1 voltage, Indicates battery pack B 1 voltage, Indicates battery pack B 1 voltage, Indicates battery pack B 1 voltage, Indicates battery pack B The instantaneous current of 1 Indicates battery pack B The instantaneous current of 2, Indicates battery pack B 3 instantaneous current, Indicates battery pack B 4 instantaneous current, T s Indicates the switching cycle.

[0056] Based on the above expression for battery-side power, the simplified model for determining the relationship between battery-side power and battery-side current is as follows: P = U · i b in, P Indicates battery-side power. URepresents the voltage vector. i b This indicates the battery-side current.

[0057] In order to establish the coupling relationship matrix from the battery side current to the resonant current, in some specific embodiments of this application, for S12, establishing the coupling relationship matrix from the battery side current to the resonant current can be done using S121 to S124.

[0058] S121, establish the relationship matrix between the resonant current and the AC port current of the half-bridge.

[0059] Specifically, the relationship between the resonant current and the AC port current of the half-bridge is as follows: in, This indicates the AC port current of the first half-bridge module. This indicates the AC port current of the second half-bridge module. This indicates the AC port current of the third half-bridge module. This indicates the AC port current of the fourth half-bridge module. This represents the resonant current of the first resonant cavity. This represents the resonant current of the second resonant cavity. This represents the resonant current of the third resonant cavity.

[0060] The relationship between the resonant current and the AC port current of the half-bridge can be simplified as follows: i k =H 1 ·i r in, i k This indicates the AC port current of the half-bridge. i r Indicates the resonant current. H 1 represents the matrix relating the resonant current to the AC port current of the half-bridge.

[0061] Among them, the relationship matrix between the resonant current and the AC port current of the half-bridge is shown. H 1. As follows: .

[0062] S122, establish the relationship matrix between the AC port current and the DC port current of the half-bridge.

[0063] Specifically, the relationship between the AC port current and the DC port current of the half-bridge is as follows: in, This indicates the DC port current of the first half-bridge module. This indicates the DC port current of the second half-bridge module. This indicates the DC port current of the third half-bridge module. This indicates the DC port current of the fourth half-bridge module. S 11 Indicates switching device S 11 The switching function, 1- s 11 Indicates switching device S 12 The switching function, s 21 Indicates switching device S 21 The switching function, 1- s 21 Indicates switching device S 22 The switching function, s 31 Indicates switching device S 31 The switching function, 1- s 31 Indicates switching device S 32 The switching function, s 41 Indicates switching device S 41 The switching function, This indicates the AC port current of the first half-bridge module. This indicates the AC port current of the second half-bridge module. This indicates the AC port current of the third half-bridge module. This indicates the AC port current of the fourth half-bridge module.

[0064] The relationship between the AC port current and the DC port current of the half-bridge can be simplified as follows: i m =H 2· i k in, i m This indicates the DC port current of the half-bridge. i k This indicates the AC port current of the half-bridge. H 2 represents the matrix showing the relationship between the AC port current and the DC port current of the half-bridge. Relationship matrix between AC port current and DC port current of half-bridge H 2 is: S123, establish the relationship matrix between the DC port current of the half-bridge and the battery side current.

[0065] Specifically, the relationship between the DC port current of the half-bridge and the battery-side current is as follows: in, Indicates battery pack B The instantaneous current of 1 Indicates battery pack B The instantaneous current of 2, Indicates battery pack B 3 instantaneous current, Indicates battery pack B 4 instantaneous current, This indicates the DC port current of the first half-bridge module. This indicates the DC port current of the second half-bridge module. This indicates the DC port current of the third half-bridge module. This indicates the DC port current of the fourth half-bridge module.

[0066] The relationship between the DC port current of the half-bridge and the battery-side current can be simplified as follows: i b =H 3· i m in, i b Indicates the battery-side current. i m This indicates the DC port current of the half-bridge. H 3 represents the matrix showing the relationship between the DC port current of the half-bridge and the battery-side current.

[0067] Among them, the relationship matrix between the DC port current of the half-bridge and the battery side current. H 3 is: .

[0068] S124. Based on the relationship matrix between the resonant current and the AC port current of the half-bridge, the relationship matrix between the AC port current of the half-bridge and the DC port current of the half-bridge, and the relationship matrix between the DC port current of the half-bridge and the battery side current, determine the coupling relationship between the battery side current and the resonant current.

[0069] Specifically, the coupling relationship between the final battery-side current and the resonant cavity branch current is as follows: i b =H 1 H 2 H 3· ir in, i b Indicates the battery-side current. H 1 represents the matrix relating the resonant current to the AC port current of the half-bridge. H 2 represents the matrix showing the relationship between the AC port current and the DC port current of the half-bridge. H 3 represents the matrix showing the relationship between the DC port current of the half-bridge and the battery-side current. i r This represents the resonant current.

[0070] in, H 1 H 2 H 3 is: .

[0071] The embodiments described above in this application reveal the complete coupling relationship between the battery-side current and the resonant current of the resonant cavity branch by establishing the relationship matrix between the resonant current and the AC port current of the half-bridge, the relationship matrix between the AC port current of the half-bridge and the DC port current of the half-bridge, and the relationship matrix between the DC port current of the half-bridge and the battery-side current, thus clarifying the coupling relationship of the multi-path coupling circuit.

[0072] To determine the mapping relationship between the resonant current and the absolute phase shift ratio under phase-shift control, in some specific embodiments of this application, for S13, establishing the mapping relationship between the resonant current and the absolute phase shift ratio under phase-shift control can be achieved by: First, the resonant interactive power is defined based on the power transfer of a single module. A single module represents a single resonant switched-capacitor converter unit, as shown in the reference... Figure 4 As shown, it includes two battery packs, two half-bridge modules, and a resonant cavity.

[0073] Specifically, the two battery packs include battery packs B 1 and battery pack B 2. The two half-bridge modules include four switching devices, namely the switching devices... S 1. Switching devices S 2. Switching devices S 3. Switching devices S 4. The resonant cavity includes a resonant inductor. L r and a resonant capacitor C r resonant inductor and resonant capacitor They are connected in series to form an LC branch.

[0074] The DC ports of the two half-bridge modules of the resonant switched capacitor converter unit are respectively connected to the battery pack. B 1 and battery packB 2. Parallel connection, wherein the battery pack B The voltage of 1 is U 1. Battery pack B The voltage of 2 is U 2. The AC port of one half-bridge module of the resonant switched capacitor converter unit is connected to the AC port of the other half-bridge module through the LC branch.

[0075] Reference Figure 4 As shown, the topology of this resonant switched capacitor converter unit uses four switching devices to achieve bidirectional power flow. In phase-shift control mode, the upper and lower transistors of each half-bridge module of the resonant switched capacitor converter unit are complementaryly turned on with a 50% duty cycle. Simultaneously, the phase shift time difference between the upper transistors of two adjacent half-bridge modules is... D 12 · T s ,in, D 12 Indicates battery pack B The two parallel half-bridge modules lag behind the battery pack. B The shift ratio of 1 parallel half-bridge module. In one switching cycle T s There are four modes: Mode 1 ( t 0- t 1): S 1 and S 4. On, input voltage U 1, U 2. Applied to the resonant cavity.

[0076] Mode 2 ( t 1- t 2): S 1 and S 3. On, input voltage U 1 is applied to the resonant cavity.

[0077] Mode 3 ( t 2- t 3): S 2 and S 3. When the circuit is open, no external voltage is applied to the resonant cavity.

[0078] Mode 4 ( t 3- t 4): S 2 and S 4. On, input voltage U 2. Applied to the resonant cavity.

[0079] The interaction power of a single resonant switched capacitor converter (RSCC) module is defined as follows: in, Indicates battery pack B 1 power, Indicates battery pack B 2 power, Indicates battery pack B 1 voltage, Indicates battery pack B 1 voltage, Indicates battery pack B The instantaneous current of 1 Indicates battery pack B The instantaneous current of 2, This represents the resonant current of the first resonant cavity. S 11 Indicates switching device S 11 The switching function, s 21 Indicates switching device S 21 The switching function.

[0080] P 12 The calculation method is as follows: in, P 12 Indicates battery pack B 1. Transfer to battery pack B The power is 2, where K represents the ratio of the switching frequency to the resonant frequency. D 12 Indicates battery pack B The two parallel half-bridge modules lag behind the battery pack. B Compared to the displacement of a parallel half-bridge module, This represents the characteristic impedance of the resonant cavity.

[0081] Further determine the multi-module P ij The definition, due to the existence of coupling loops in the multi-module structure, its physical meaning is no longer that of a battery pack. B i and battery pack B j The power of interaction is defined only as a mathematical expression.

[0082] in, P 23 Indicates battery pack B 2. Transfer to battery packB 3 power, Represents the resonant current of the second resonant cavity, 1- s 31 Indicates switching device S 32 The switching function.

[0083] in, P 34 Indicates battery pack B 3. Transfer to battery pack B 4 power, Represents the resonant current of the third resonant cavity, 1- s 41 Indicates switching device S 42 The switching function.

[0084] After linearizing the above formula, we get: ; ; ; in, express arrive The transfer function, express arrive The transfer function, express arrive The transfer function.

[0085] Based on the above formula, the mapping relationship between the resonant current and the absolute shift ratio is determined. After linearization, the transfer function of the battery-side power P and the absolute shift ratio D is obtained as follows: P=G PD · D in, P Indicates battery-side power. G PD This represents the coupling matrix between battery-side power and absolute shift. D This indicates an absolute shift.

[0086] To construct the coupling matrix between battery-side power and absolute shift ratio, for S14, based on the relationship model between battery-side power and battery-side current, the coupling matrix from battery-side current to resonant current, and the mapping relationship between resonant current and absolute shift ratio, the coupling matrix between battery-side power and absolute shift ratio can be constructed using the following method: Integrating the results of steps S11 to S13 above, a coupling matrix between battery-side power and absolute shift ratio is established. The derivation process is as follows: Adding the common-mode power component P— from the series circuit, we get: in, Compared to the absolute shift of the second half-bridge module, Compared to the absolute shift of the third half-bridge module, This indicates the absolute shift ratio of the fourth half-bridge module.

[0087] The above formula can be simplified as: P=H PD · D in, P Indicates battery-side power. H PD This represents the coupling matrix between battery-side power and absolute shift. D This indicates an absolute shift.

[0088] The embodiments described above in this application establish a relationship model between battery-side power and battery-side current, a coupling relationship matrix between battery-side current and resonant current, and a mapping relationship between resonant current under phase-shift control and absolute phase shift ratio. This constructs a coupling matrix between battery-side power and absolute phase shift ratio, revealing the coupling relationship based on a switch-multiplexed multi-resonant switched-capacitor converter, and laying the foundation for the realization of power decoupling.

[0089] To effectively achieve power decoupling, in some specific embodiments of this application, for S15, a diagonal matrix is ​​extracted from the coupling matrix of battery-side power compared to absolute shift, and a relationship between the new output variable and the new input variable after decoupling control is established. This can be achieved by: Extract the diagonal matrix from the coupling matrix of battery-side power and absolute shift, and multiply both sides of the equation of the diagonal matrix by the inverse of the remaining matrix to determine the relationship between the new output variable and the new input variable after decoupling control. Where Y' represents the new target output vector and X' represents the new input variable.

[0090] Simplifying the above equation, the new relation for the output variable is: Y'=H 4 -1 P ; in, Y’ This represents the new target output vector.P This represents the original target output vector. H 4 -1 This represents the first transformation matrix; The new relation for the input variables is: X'=H 5 D in, X’ This represents the new input variable. H 5 represents the second transformation matrix. D This represents the original input variables.

[0091] The embodiments described above in this application extract a diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and multiply both sides of the equation by the inverse of the remaining matrix to form new output variables and new input variables. This enables the conversion from a multi-input multi-output system to multiple single-input single-output systems, effectively decoupling multiple coupled loops and improving the systematicity and feasibility of decoupling control.

[0092] In some specific embodiments of this application, for S16, open-loop control is used to determine the new target output vector value, the new input variable value, and the original input variable value based on the original target output vector value, the new output variable relationship, and the new input variable relationship, including: S161 to S163.

[0093] S161, input the original target output vector value into the relational expression of the new output variable after decoupling control, and determine the value that the new target output vector should have.

[0094] The above step S161 is executed, using the new relational expression for the output variable: The new relation for the output variable is: Y'=H 4 -1 P ; in, Y’ This represents the new target output vector. P This represents the original target output vector. H 4 -1 This represents the first transformation matrix.

[0095] Specifically, the input is the original target output vector. P ref Through the first transformation matrix H 4 -1 Get new output variables Y’ ref : Y’ ref =H 4 -1 P ref S162, based on the expected value of the new target output vector, determines the expected value of the new input variable through open-loop control.

[0096] Specifically, a diagonal matrix can also be used to obtain the desired values ​​of new input variables through open-loop control. For example, the diagonal matrix is: S163. Based on the expected values ​​of the new input variables and the relationship between the new input variables, the second transformation matrix is ​​used to determine the expected values ​​of the original input variables.

[0097] The above step S163 is executed, using the new relational expression for the input variables: The new relation for the input variables is: X'=H 5 D in, X’ This represents the new input variable. H 5 represents the second transformation matrix. D This represents the original input variables.

[0098] Specifically, a new input variable X' is input, and then processed through the second transformation matrix. H 5. Obtain the original input variable's expected value X.

[0099] X= H 5X' In some specific embodiments of this application, in order to improve the dynamic response and control accuracy during load switching, the control method can be replaced by proportional-integral closed-loop control by collecting battery-side power as a feedback signal.

[0100] Other unit modules in the above embodiments, such as signal acquisition, phase-shift modulation, linearization for transfer function calculation, proportional-integral control, etc., which are not described in detail, can all be implemented using existing technologies.

[0101] This application provides a power decoupling method based on a switch-multiplexed multi-resonant switched-capacitor converter. By constructing a coupling matrix between battery-side power and absolute shift ratio, the coupling relationship of the switch-multiplexed multi-resonant switched-capacitor converter is determined. By extracting the diagonal matrix, a new relationship between the output variable and the new relationship between the input variable are constructed, thereby achieving power decoupling. This converts multiple inputs and multiple outputs into multiple single inputs and single outputs. Combined with open-loop control, effective decoupling control of each channel is achieved, significantly improving control accuracy and dynamic response performance. It solves the mutual interference problem existing in traditional control methods and is suitable for the equalization control of battery energy storage systems.

[0102] Figure 5 This is a schematic diagram of open-loop control of a switch-multiplexed multiresonant switched-capacitor converter unit according to an exemplary embodiment.

[0103] Reference Figure 5 The diagram shown illustrates the decoupling control of a series balancing switch for n batteries. set up: ; First, according to Y’ ref =H 4 -1 P ref Get: ; Then, from Y’ ref A diagonal matrix can be used to get to X'. Open-loop control acquisition.

[0104] Finally, the absolute shift from X' to X can be achieved through X= H 5X', where X contains the absolute shift ratio D signal, is input to the drive signals of each half-bridge module of the multi-resonant switched-capacitor converter, thereby controlling the power of each battery to reach a given value. P ref .

[0105] Figure 6 This is a schematic diagram of closed-loop control of a switch-multiplexed multiresonant switched-capacitor converter unit according to an exemplary embodiment.

[0106] Reference Figure 6 A block diagram of a series-connected balanced closed-loop decoupling control for n batteries.

[0107] set up: ; First, according to according to Y’ ref=H 4 -1 P ref Get: ; Then because from Y’ ref X' is a diagonal matrix relationship, with each channel being independent and decoupled from the others. To improve control accuracy and dynamic response, a proportional-integral controller can be used for closed-loop control to obtain the value of X'.

[0108] Finally, the route from X' to X can be obtained via X= H 5X', the absolute shift ratio signal D contained in X is input to the drive signals of each half-bridge module of the multi-resonant switched capacitor converter, thereby controlling the power of each battery to reach a given value. P ref .

[0109] Figure 7 This is a schematic diagram of the steady-state battery-side current waveform of a 4-battery prototype after power decoupling control, according to an exemplary embodiment.

[0110] Reference Figure 7 As shown, Figure 7 In diagram (a), the current waveform on the battery side during steady state is shown. Figure 7 (b) shows the waveforms of the instantaneous current in each resonant cavity during power transmission in Condition 3, using Condition 3 as an example.

[0111] In Condition 1, the power of each battery is [1p.u., -2p.u., 2p.u., -1p.u.]; Condition 2 shows the reverse power transfer in Condition 1; Condition 3 shows [-1p.u., 2p.u., 0, -2p.u.]; Condition 4 shows the reverse power transfer in Condition 3.

[0112] Reference Figure 7 As shown, the waveforms for the four operating conditions respectively verify the effectiveness of the decoupling control under different power distributions.

[0113] Figure 8 This is a schematic diagram of a power decoupling system based on a switch-multiplexed multi-resonant switched-capacitor converter, according to an exemplary embodiment.

[0114] Reference Figure 8 As shown in one embodiment of this application, a power decoupling system structure 100 based on a switch-multiplexed multi-resonant switched-capacitor converter is provided, including: a first module 110, a second module 120, a third module 130, a coupling relationship determination module 140, a first coupling relationship decoupling module 150, and a second coupling relationship decoupling module 160.

[0115] The first module 110 is used to establish a model of the relationship between battery-side power and battery-side current. The second module 120 is used to establish the coupling relationship matrix from the battery-side current to the resonant current; The third module 130 is used to establish the mapping relationship between the resonant current and the absolute phase shift under phase shift control; The coupling relationship determination module 140 is used to construct the coupling matrix between battery-side power and absolute shift ratio based on the relationship model between battery-side power and battery-side current, the coupling relationship matrix from battery-side current to resonant current, and the mapping relationship between resonant current and absolute shift ratio. The first decoupling module 150 is used to extract the diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and to construct the relationship between the new output variable and the new input variable after decoupling control based on the diagonal matrix. The second decoupling module 160 is used to determine the new target output vector value, the new input variable value, and the original input variable value through open-loop control, based on the original target output vector value, the new output variable relationship formula, and the new input variable relationship formula.

[0116] The embodiments described above in this application establish a relationship model between battery-side power and battery-side current, analyze the coupling relationship matrix between battery-side current and resonant current, and construct a coupling matrix between battery-side power and absolute shift ratio by combining the mapping relationship between resonant current and absolute shift ratio. By extracting the diagonal matrix, new relationships between output variables and new relationships between input variables are constructed, thereby achieving power decoupling. This converts multiple inputs and multiple outputs into multiple single inputs and single outputs. Combined with open-loop control, effective decoupling control of each channel is achieved, significantly improving control accuracy and dynamic response performance. This solves the mutual interference problem existing in traditional control methods and is suitable for the balanced control of battery energy storage systems.

[0117] Regarding the embodiments of the above system, the specific ways in which each module performs operations have been described in detail in the embodiments of the method, and will not be elaborated here.

[0118] Based on the same technical concept, in some specific embodiments of this application, a terminal includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and a method that the processor can use to execute when executing the program.

[0119] Based on the same technical concept, in some specific embodiments of this application, a computer-readable storage medium is provided on which a computer program is stored, which can be used to execute a method when the program is executed by a processor.

[0120] Optionally, the memory is used to store programs; the memory may include volatile memory, such as random-access memory (RAM), such as static random-access memory (SRAM), double data rate synchronous dynamic random-access memory (DDR SDRAM), etc.; the memory may also include non-volatile memory, such as flash memory. The memory is used to store computer programs (such as application programs and functional modules that implement the above methods), computer instructions, etc., and the aforementioned computer programs and computer instructions can be partitioned and stored in one or more memories. Furthermore, the aforementioned computer programs, computer instructions, data, etc., can be accessed by the processor.

[0121] The aforementioned computer programs, computer instructions, etc., can be stored in partitions within one or more memory locations. Furthermore, the aforementioned computer programs, computer instructions, data, etc., can be accessed by a processor.

[0122] A processor is used to execute a computer program stored in memory to implement the various steps of the methods involved in the above embodiments. For details, please refer to the relevant descriptions in the preceding method embodiments.

[0123] The processor and memory can be separate structures or integrated structures. When the processor and memory are separate structures, they can be coupled together via a bus.

[0124] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can 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.) containing computer-usable program code.

[0125] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0126] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0127] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0128] The foregoing has described some specific embodiments of this application. It should be understood that this application is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the substantive content of this application. The above-described preferred features can be used in any combination without conflict.

Claims

1. A power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter, characterized in that, include: Establish a model relating battery-side power to battery-side current; Establish the coupling relationship matrix between the battery-side current and the resonant current; Establish the mapping relationship between the resonant current and the absolute phase shift under phase-shift control; Based on the relationship model between the battery-side power and the battery-side current, the coupling relationship matrix between the battery-side current and the resonant current, and the mapping relationship between the resonant current and the absolute shift ratio, a coupling matrix between the battery-side power and the absolute shift ratio is constructed. Extract the diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and establish the relationship between the new output variable and the new input variable after decoupling control; Based on the original target output vector value, the relationship between the new output variables and the new input variables, open-loop control is used to determine the values ​​that the new target output vector should have, the values ​​that the new input variables should have, and the values ​​that the original input variables should have.

2. The power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to claim 1, characterized in that, The establishment of the coupling relationship matrix from the battery-side current to the resonant current includes: Establish the relationship matrix between the resonant current and the AC port current of the half-bridge; Establish the relationship matrix between the AC port current and the DC port current of the half-bridge; Establish a matrix relating the DC port current of the half-bridge to the battery-side current; Based on the relationship matrix between the resonant current and the half-bridge AC port current, the relationship matrix between the half-bridge AC port current and the half-bridge DC port current, and the relationship matrix between the half-bridge DC port current and the battery-side current, the coupling relationship between the battery-side current and the resonant current is determined.

3. The power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to claim 2, characterized in that, The relationship matrix between the resonant current and the AC port current of the half-bridge is as follows: H 1: i k =H 1 ·i r in, i k This represents the AC port current of the half-bridge. i r This represents the resonant current. H 1 represents the matrix relating the resonant current to the AC port current of the half-bridge; The relationship matrix between the AC port current and the DC port current of the half-bridge H 2 is represented as: i m =H 2· i k in, i m This represents the DC port current of the half-bridge. i k This represents the AC port current of the half-bridge. H 2 represents the relationship matrix between the AC port current and the DC port current of the half-bridge; The relationship matrix between the DC port current of the half-bridge and the battery-side current H 3 is represented as: i b =H 3· i m in, i b This indicates the battery-side current. i m This represents the DC port current of the half-bridge. H 3 represents the matrix relating the DC port current of the half-bridge to the battery-side current; The coupling relationship between the battery-side current and the resonant current is as follows: i b =H 1 H 2 H 3· i r in, i b This indicates the battery-side current. H 1 represents the matrix relating the resonant current to the AC port current of the half-bridge. H 2 represents the matrix showing the relationship between the AC port current and the DC port current of the half-bridge. H 3 represents the matrix showing the relationship between the DC port current of the half-bridge and the battery-side current. i r This represents the resonant current.

4. The power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to claim 1, characterized in that, The relationship model between the battery-side power and the battery-side current is as follows: P = U · i b in, P This indicates the battery-side power. U Represents the voltage vector. i b This indicates the battery-side current.

5. The power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to claim 1, characterized in that, The mapping relationship between the resonant current and the absolute phase shift under the phase shift control is as follows: ； ； in, i r This represents the resonant current. U Represents the voltage vector. Indicates the characteristic impedance of the resonant cavity. D Compared to the absolute shift, Indicates resonant inductance. Indicates the resonant capacitance; The coupling matrix between the battery-side power and the absolute shift H PD for: P=H PD · D in, P This indicates the battery-side power. H PD The coupling matrix represents the ratio of the battery-side power to the absolute shift. D This indicates the absolute shift ratio.

6. The power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to claim 1, characterized in that, The step of extracting a diagonal matrix from the coupling matrix comparing the battery-side power with the absolute shift, and constructing a new relationship between the output variables and the input variables after decoupling control based on the diagonal matrix, includes: Extract the diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and multiply both sides of the equation of the diagonal matrix by the inverse of the remaining matrix to determine the relationship between the new output variable and the new input variable after decoupling control. The relationship between the new output variables after decoupling control is as follows: Y'=H 4 -1 P ； in, Y’ This represents the new target output vector. P This represents the original target output vector. H 4 -1 This represents the first transformation matrix; The relational expression for the new input variables is: X'=H 5 D in, X’ This represents a new input variable. H 5 represents the second transformation matrix. D This represents the original input variables.

7. The power decoupling method based on a switch-multiplexed multiresonant switched-capacitor converter according to claim 6, characterized in that, The step of determining the required values ​​of the new target output vector, the new input variables, and the original input variables using open-loop control based on the original target output vector value, the new output variable relationship, and the new input variable relationship includes: The original target output vector value is input into the relational expression of the new output variable after decoupling control to determine the value that the new target output vector should have. Based on the expected value of the new target output vector, the expected value of the new input variable is determined through open-loop control; Based on the expected values ​​of the new input variables and the relationship between the new input variables, the expected values ​​of the original input variables are determined using the second transformation matrix.

8. A power decoupling system based on a switch-multiplexed multiresonant switched-capacitor converter, characterized in that, include: The first module is used to establish a model of the relationship between battery-side power and battery-side current. The second module is used to establish the coupling relationship matrix from the battery-side current to the resonant current; The third module is used to establish the mapping relationship between the resonant current and the absolute phase shift under phase shift control; The coupling relationship determination module is used to construct the coupling matrix between the battery-side power and the absolute shift ratio based on the relationship model between the battery-side power and the battery-side current, the coupling relationship matrix between the battery-side current and the resonant current, and the mapping relationship between the resonant current and the absolute shift ratio. The first decoupling module is used to extract a diagonal matrix from the coupling matrix of the battery-side power and the absolute shift, and to construct a new relationship between the output variables and the input variables after decoupling control based on the diagonal matrix. The second decoupling module is used to determine the values ​​of the new target output vector, the new input variables, and the original input variables through open-loop control, based on the original target output vector value, the relationship between the new output variables, and the relationship between the new input variables.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method described in any one of claims 1-7.

10. An electronic device, characterized in that, include: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the method according to any one of claims 1-7.

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