A high-efficiency single-stage bidirectional ac-dc converter current configuration method and related apparatus

Abstract

The application discloses a high-efficiency single-stage bidirectional AC-DC converter current construction method and related devices. The method provided by the application first collects the input voltage and input current of the AC side of the single-stage bidirectional AC-DC converter, then converts the collected voltage signal and current signal into voltage components and current components in the coordinate system and the dq coordinate system, respectively, determines the instantaneous power relationship formula in the corresponding coordinate system according to the voltage components and current components in the corresponding coordinate system, and then constructs the orthogonal current relationship equation by simultaneously solving the instantaneous power relationship formulas in the two coordinate systems. The current value of the beta-axis orthogonal current is calculated through the orthogonal current relationship equation. The scheme provided by the application can quickly construct the axis current component without relying on the inductance value of the grid-side input end LC filter, can avoid the influence caused by the error of the inductance value of the LC filter due to the aging of the circuit device, and solves the technical problem of low construction accuracy of the axis orthogonal current component.

Description

Technical Field

[0001] This application relates to the field of converter technology, and in particular to a method for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter and related devices. Background Technology

[0002] Single-stage bidirectional AC-DC converters feature bidirectional power transmission, high power density, controllable AC-side power factor, and electrical isolation. Currently, the bidirectional single-stage isolated AC-DC matrix converter topology used in bidirectional charging devices is as follows: Figure 1 As shown.

[0003] Commonly used control methods for bidirectional single-stage isolated AC-DC matrix converters include: one is to directly control the grid current using a PR (Proportional Resonance) controller in a stationary reference coordinate system. The PR controller has a simple structure and is easy to implement, and can achieve zero steady-state error tracking of the AC given signal, but this controller is relatively sensitive to grid voltage and frequency disturbances; the other is to transform the sinusoidal current into coordinates and use a PI (Proportional Integral) controller in a synchronous reference coordinate system. In the synchronous dq coordinate system, the PI-based regulation method can not only achieve independent control of active and reactive currents, but also achieve zero steady-state error control of the input current.

[0004] In the implementation of a single-stage bidirectional AC-DC converter using a PI controller, among other methods... Axis current components The construction efficiency and accuracy play a crucial role in the overall control effect. In practical use, the circuit components in the converter will age over time. However, existing... Orthogonal current components of the axis The construction algorithm relies too heavily on circuit parameters, leading to limitations in existing single-stage bidirectional AC-DC converter control techniques. The technical problem of low accuracy in constructing orthogonal current components of axes. Summary of the Invention

[0005] This application provides a method and related apparatus for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter, which addresses the shortcomings of existing single-stage bidirectional AC-DC converter control technologies. The technical problem of low accuracy in constructing orthogonal current components of axes.

[0006] To address the aforementioned technical problems, the first aspect of this application provides a method for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter, applied to a single-stage bidirectional AC-DC converter. The single-stage bidirectional AC-DC converter includes: an LC filter circuit, a matrix converter circuit, a high-frequency transformer, an LCL resonant circuit, an H-bridge circuit, and an output filter circuit. The current construction method includes:

[0007] Based on the single-stage bidirectional AC-DC converter, obtain the AC side input voltage and AC side input current of the single-stage bidirectional AC-DC converter;

[0008] The AC input voltage and AC input current are converted into their respective coordinate systems through coordinate transformation. The first voltage component and the first current component in the dq coordinate system, and the second voltage component and the second current component in the dq coordinate system;

[0009] Based on the first voltage component and the first current component, determine The power relationship at the first instant in the coordinate system;

[0010] Based on the second voltage component and the second current component, determine the second instantaneous power relationship in the dq coordinate system;

[0011] Based on the first instantaneous power relationship and the second instantaneous power relationship, an orthogonal current relationship equation is constructed to calculate the current value of the β-axis orthogonal current through the orthogonal current relationship equation.

[0012] Preferably, the orthogonal current relationship equation is specifically as follows:

[0013]

[0014] In the formula, The β-axis orthogonal current, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. For AC side input voltage at β-axis voltage component in coordinate system This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. This represents the q-axis current component of the AC input current in the dq coordinate system. For AC side input voltage at Voltage component along the α-axis in the coordinate system.

[0015] Preferably, the first instantaneous power relationship is as follows:

[0016]

[0017] In the formula, For AC side input voltage at Voltage component along the α-axis in the coordinate system For AC side input voltage at β-axis voltage component in coordinate system The β-axis orthogonal current, For AC side input current at The α-axis current component in the coordinate system, P1 is Instantaneous active power in the coordinate system, Q1 is Instantaneous reactive power in the coordinate system.

[0018] Preferably, the second instantaneous power relationship is as follows:

[0019]

[0020] In the formula, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. P1 represents the q-axis current component of the AC input current in the dq coordinate system, P2 represents the instantaneous active power in the dq coordinate system, and Q2 represents the instantaneous reactive power in the dq coordinate system.

[0021] Meanwhile, a second aspect of this application provides a high-efficiency single-stage bidirectional AC-DC converter current configuration device, applied to a single-stage bidirectional AC-DC converter. The single-stage bidirectional AC-DC converter includes: an LC filter circuit, a matrix converter circuit, a high-frequency transformer, an LCL resonant circuit, an H-bridge circuit, and an output filter circuit. The current configuration device includes:

[0022] An electrical signal acquisition unit is used to acquire the AC side input voltage and AC side input current of the single-stage bidirectional AC-DC converter based on the single-stage bidirectional AC-DC converter.

[0023] The electrical signal component conversion unit is used to convert the AC input voltage and the AC input current into electrical signals respectively through coordinate system transformation. The first voltage component and the first current component in the dq coordinate system, and the second voltage component and the second current component in the dq coordinate system;

[0024] The first power relationship determination unit is used to determine, based on the first voltage component and the first current component, the following: The power relationship at the first instant in the coordinate system;

[0025] The second power relationship determination unit is used to determine the second instantaneous power relationship in the dq coordinate system based on the second voltage component and the second current component.

[0026] The orthogonal current determination unit is used to construct an orthogonal current relationship equation based on the first instantaneous power relationship equation and the second instantaneous power relationship equation, so as to calculate the current value of the β-axis orthogonal current through the orthogonal current relationship equation.

[0027] Preferably, the orthogonal current relationship equation is specifically as follows:

[0028]

[0029] In the formula, The β-axis orthogonal current, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. For AC side input voltage at β-axis voltage component in coordinate system This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. This represents the q-axis current component of the AC input current in the dq coordinate system. For AC side input voltage at Voltage component along the α-axis in the coordinate system.

[0030] Preferably, the first instantaneous power relationship is as follows:

[0031]

[0032] In the formula, For AC side input voltage at Voltage component along the α-axis in the coordinate system For AC side input voltage at β-axis voltage component in coordinate system The β-axis orthogonal current, For AC side input current at The α-axis current component in the coordinate system, P1 is Instantaneous active power in the coordinate system, Q1 is Instantaneous reactive power in the coordinate system.

[0033] Preferably, the second instantaneous power relationship is as follows:

[0034]

[0035] In the formula, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. P1 represents the q-axis current component of the AC input current in the dq coordinate system, P2 represents the instantaneous active power in the dq coordinate system, and Q2 represents the instantaneous reactive power in the dq coordinate system.

[0036] A third aspect of this application provides a high-efficiency single-stage bidirectional AC-DC converter current construction terminal, including: a memory and a processor;

[0037] The memory is used to store program code, which is used to implement a high-efficiency single-stage bidirectional AC-DC converter current construction method as provided in the first aspect of this application.

[0038] The processor is used to read and execute the program code.

[0039] The fourth aspect of this application provides a computer-readable storage medium storing program code that is read and executed by a processor to implement a high-efficiency single-stage bidirectional AC-DC converter current construction method as provided in the first aspect of this application.

[0040] As can be seen from the above technical solutions, this application has the following advantages:

[0041] The method provided in this application first acquires the input voltage and input current on the AC side of a single-stage bidirectional AC-DC converter, and then converts the acquired voltage and current signals into... The voltage and current components in the dq coordinate system are determined, and the instantaneous power relationship in the corresponding coordinate system is determined based on the voltage and current components in the corresponding coordinate system. Then, by simultaneously solving the instantaneous power relationship in the two coordinate systems, an orthogonal current relationship equation is constructed. The current value of the β-axis orthogonal current is calculated using the orthogonal current relationship equation. The solution provided in this application can quickly construct a [current relationship] without relying on the inductance value of the LC filter at the grid input terminal. Axis current components This avoids the error caused by the aging of circuit components such as the inductance value of the LC filter, and solves the problems existing in the control technology of single-stage bidirectional AC-DC converters. The technical problem of low accuracy in constructing orthogonal current components of axes. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a circuit topology diagram of a single-phase, single-stage LCL type bidirectional AC-DC converter.

[0044] Figure 2 This is a flowchart illustrating an embodiment of a high-efficiency single-stage bidirectional AC-DC converter current construction method provided in this application.

[0045] Figure 3 The control logic block diagram of the single-phase, single-stage LCL bidirectional AC-DC converter provided in this application is shown.

[0046] Figure 4(a) shows the grid-side voltage and grid-side current waveforms of a single-phase single-stage LCL bidirectional AC-DC converter under the first current condition, based on a current construction method for an efficient single-stage bidirectional AC-DC converter provided in this application.

[0047] Figure 4(b) shows the grid-side voltage and grid-side current waveforms of a single-phase single-stage LCL bidirectional AC-DC converter under the second current condition, based on the current construction method of this application.

[0048] Figure 4(c) shows the grid-side voltage and grid-side current waveforms of a single-phase single-stage LCL bidirectional AC-DC converter under the third current condition, based on the current construction method of this application.

[0049] Figure 5 Based on the efficient single-stage bidirectional AC-DC converter current construction method provided in this application and existing algorithms, Comparison of the effects of orthogonal current components on the axes.

[0050] Figure 6 This is a schematic diagram of an embodiment of a high-efficiency single-stage bidirectional AC-DC converter current configuration device provided in this application.

[0051] Figure 7 This is a schematic diagram of a current-construction terminal embodiment of a high-efficiency single-stage bidirectional AC-DC converter provided in this application. Detailed Implementation

[0052] In practical applications of single-stage bidirectional AC-DC converters, the circuit components will age over time, especially in high-power applications where the operating current is often large. This increased inductor operating current causes DC bias in the magnetic core, leading to significant distortion of the input inductor value. This further widens the error between the actual inductor value and the value used in the algorithm. Existing... Orthogonal current components of the axis The construction algorithm is as follows:

[0053]

[0054] In the formula, The current is orthogonal to the β-axis. This represents the β-axis component of the input voltage. This represents the β-axis component of the filter capacitor voltage. The equivalent inductance of the equivalent circuit. For the Laplace operator.

[0055] This Orthogonal current components of the axis The construction algorithm relies excessively on the parameters of the inductor components, leading to limitations in existing single-stage bidirectional AC-DC converter control techniques. The technical problem of low accuracy in constructing orthogonal current components of axes.

[0056] This application provides a method and related apparatus for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter, which addresses the shortcomings of existing single-stage bidirectional AC-DC converter control technologies. The technical problem of low accuracy in constructing orthogonal current components of axes.

[0057] To make the inventive objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0058] This application provides a method for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter. This method is specifically applied to a single-stage bidirectional AC-DC converter, the structure of which is as follows: Figure 1 As shown, it includes: an LC filter circuit, a matrix transformation circuit, a high-frequency transformer, an LCL resonant circuit, an H-bridge circuit, and an output filter circuit. Figure 1 As shown, AC voltage source As a DC voltage source, the output voltage of the matrix converter is denoted as... The output voltage of the DC-side full-bridge converter is denoted as... Let the switching frequencies of the two switching transistors be the same, denoted as . The corresponding switching period is denoted as The AC input current is The DC-side output current is .

[0059] Please see Figure 2 and Figure 3 The high-efficiency single-stage bidirectional AC-DC converter current construction method provided in this embodiment includes:

[0060] Step 101: Based on the single-stage bidirectional AC-DC converter, obtain the AC side input voltage and AC side input current of the single-stage bidirectional AC-DC converter;

[0061] Step 102: Convert the AC input voltage and AC input current into coordinate systems using coordinate transformation. The first voltage component and the first current component in the dq coordinate system, and the second voltage component and the second current component in the dq coordinate system;

[0062] Step 103: Determine based on the first voltage component and the first current component. The power relationship at the first instant in the coordinate system;

[0063] Step 104: Determine the second instantaneous power relationship in the dq coordinate system based on the second voltage component and the second current component;

[0064] Step 105: Based on the first instantaneous power relationship and the second instantaneous power relationship, construct the orthogonal current relationship equation, and calculate the current value of the β-axis orthogonal current through the orthogonal current relationship equation.

[0065] It should be noted that, as Figure 3 The control block diagram shown in this application illustrates the technical solution based on a single-stage bidirectional AC-DC converter requiring control, which obtains its AC side input voltage. and AC input current Then, based on the obtained AC side input voltage and AC input current Converted to The voltage and current components in the dq coordinate system and the dq coordinate system are used to construct... The power relationship equations for the dq coordinate system and the d-q coordinate system, where the power relationship at the first instant represents: The instantaneous active power P1 and instantaneous reactive power Q1 in the coordinate system are shown in equation (1).

[0066] (1)

[0067] The second instantaneous power relationship is expressed as follows: instantaneous active power P2 and instantaneous reactive power Q2 in the dq coordinate system, as shown in equation (2).

[0068] (2)

[0069] In the formula, For AC side input voltage at Voltage component along the α-axis in the coordinate system For AC side input voltage at β-axis voltage component in coordinate system The current is orthogonal to the β-axis. For AC side input current at The α-axis current component in the coordinate system, P1 is Instantaneous active power in the coordinate system, Q1 is Instantaneous reactive power in coordinate system This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. P1 represents the q-axis current component of the AC input current in the dq coordinate system, P2 represents the instantaneous active power in the dq coordinate system, and Q2 represents the instantaneous reactive power in the dq coordinate system.

[0070] Next, by combining the above simultaneous equations (1) and (2), we can obtain The expression is shown in the following formula:

[0071] (3)

[0072] When given and When changes occur, the required parameters for the entire control loop can be accurately calculated using the evolution formula of equation (3) – equation (4). .

[0073] (4)

[0074] The orthogonal current construction logic provided in this embodiment takes into account the specific circuit structure and operating principle of the single-phase single-stage LCL bidirectional AC-DC converter. The calculation logic is highly targeted and can give full play to the performance advantages of the single-phase single-stage LCL bidirectional AC-DC converter. Furthermore, by cross-linking the electrical parameters of the dual coordinate system, the control accuracy of the D-axis current and Q-axis current can be improved.

[0075] To verify the decoupling control strategy and construction proposed in this application Advantages of the axis current algorithm. This embodiment builds two simulation models for comparison on the Matlab Simulink platform. The specific input and output specifications of the simulation models are: input AC voltage of 220V, 50Hz, and output DC voltage of 400V. In both simulation models, all parameters of the topology used in this embodiment are consistent, and the simulation step size is consistent. Then, complete closed-loop control models are built for each. One of these closed-loop control models is constructed using a second-order generalized integral algorithm. Another set of shaft currents is constructed using the algorithm proposed in this paper. Axis current. Experimental results are shown in Figures 4(a) to 4(c) and Figure 5 As shown. Figure 4(a) shows the setting of the d-axis reference current in this embodiment. q-axis reference current The waveforms of the grid-side input voltage and grid-side input current obtained under the given conditions are shown in Figure 4(b). From this figure, it can be seen that the power factor angle can be controlled to zero using this application. Figure 4(b) shows the d-axis reference current set in this embodiment. q-axis reference current The waveforms of the grid-side input voltage and grid-side input current obtained under the given conditions are shown. It can also be seen that the power factor angle can be controlled using this application. Figure 4(c) shows the setting of the d-axis reference current in this embodiment. q-axis reference current The waveforms of the grid-side input voltage and grid-side input current obtained under the given conditions are shown. It can also be seen that the power factor angle can be controlled using this application. .exist Figure 5 This embodiment illustrates the construction proposed in this application. A comparison of the performance of the axis current algorithm and the second-order generalized integral (SOGI) algorithm. At power-on, the second-order generalized integral (SOGI) algorithm requires nearly 60ms to construct an accurate value. The algorithm proposed in this patent application can construct an accurate shaft current in just 10ms. The shaft current, in this embodiment, will be at 0.07s. shaft current from Switch to When faced with sudden changes in reference voltage, the algorithm proposed in this application can construct a reference voltage without delay and without error. The axis current, and the second-order generalized integral (SOGI) algorithm takes about 30ms to construct an accurate value. Axis current.

[0076] The above is a detailed description of an embodiment of the high-efficiency single-stage bidirectional AC-DC converter current construction method provided in this application. The following is a detailed description of an embodiment of a high-efficiency single-stage bidirectional AC-DC converter current construction device provided in this application.

[0077] Please see Figure 6 This application provides an embodiment of a high-efficiency single-stage bidirectional AC-DC converter current configuration device, applied to a single-stage bidirectional AC-DC converter. The single-stage bidirectional AC-DC converter includes: an LC filter circuit, a matrix converter circuit, a high-frequency transformer, an LCL resonant circuit, an H-bridge circuit, and an output filter circuit. The current configuration device includes:

[0078] The electrical signal acquisition unit 201 is used to acquire the AC side input voltage and AC side input current of the single-stage bidirectional AC-DC converter based on the single-stage bidirectional AC-DC converter.

[0079] The electrical signal component conversion unit 202 is used to convert the AC side input voltage and AC side input current into components respectively through coordinate system transformation. The first voltage component and the first current component in the dq coordinate system, and the second voltage component and the second current component in the dq coordinate system;

[0080] The first power relationship determination unit 203 is used to determine, based on the first voltage component and the first current component, the following: The power relationship at the first instant in the coordinate system;

[0081] The second power relationship determination unit 204 is used to determine the second instantaneous power relationship in the dq coordinate system based on the second voltage component and the second current component.

[0082] The orthogonal current determination unit 205 is used to construct orthogonal current relationship equations based on the first instantaneous power relationship equation and the second instantaneous power relationship equation, so as to calculate the current value of the β-axis orthogonal current through the orthogonal current relationship equation.

[0083] More specifically, the orthogonal current relationship equation is as follows:

[0084]

[0085] In the formula, The current is orthogonal to the β-axis. This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. For AC side input voltage at β-axis voltage component in coordinate system This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. This represents the q-axis current component of the AC input current in the dq coordinate system. For AC side input voltage at Voltage component along the α-axis in the coordinate system.

[0086] More specifically, the power relationship at the first instant is as follows:

[0087]

[0088] In the formula, For AC side input voltage at Voltage component along the α-axis in the coordinate system For AC side input voltage at β-axis voltage component in coordinate system The current is orthogonal to the β-axis. For AC side input current at The α-axis current component in the coordinate system, P1 is Instantaneous active power in the coordinate system, Q1 is Instantaneous reactive power in the coordinate system.

[0089] More specifically, the second instantaneous power relationship is as follows:

[0090]

[0091] In the formula, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. P1 represents the q-axis current component of the AC input current in the dq coordinate system, P2 represents the instantaneous active power in the dq coordinate system, and Q2 represents the instantaneous reactive power in the dq coordinate system.

[0092] Furthermore, this application also provides detailed descriptions of terminal embodiments and computer-readable storage medium embodiments of the high-efficiency single-stage bidirectional AC-DC converter current construction method related to the above-described high-efficiency single-stage bidirectional AC-DC converter current construction method.

[0093] like Figure 7As shown, this application also provides an embodiment of a high-efficiency single-stage bidirectional AC-DC converter current structure terminal. The terminal implementation types include, but are not limited to, personal computers, industrial computers, servers, and embedded intelligent devices. The main components of the terminal include: memory 33 and processor 31. Memory 33 and processor 31 can be connected through communication bus 34.

[0094] Memory 33 is used to store program code, which is used to implement a method for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter as mentioned in the above embodiments;

[0095] Processor 31 is used to read and execute program code.

[0096] This application provides a computer-readable storage medium storing program code, which is read and executed by a processor to implement a high-efficiency single-stage bidirectional AC-DC converter current construction method as mentioned in the above embodiments.

[0097] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the terminals, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0098] In the several embodiments provided in this application, it should be understood that the disclosed terminals, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units through some interfaces, and may be electrical, mechanical, or other forms.

[0099] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0100] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where 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 (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or 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.

[0101] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0102] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0103] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it 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 all or 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.

[0104] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter, applied to a single-stage bidirectional AC-DC converter, wherein the single-stage bidirectional AC-DC converter comprises: LC filter circuit, matrix transformation circuit, high-frequency transformer, LCL resonant circuit, H-bridge circuit, and output filter circuit, characterized in that the current construction method includes: Based on the single-stage bidirectional AC-DC converter, obtain the AC side input voltage and AC side input current of the single-stage bidirectional AC-DC converter; The AC input voltage and AC input current are converted into their respective coordinate systems through coordinate transformation. The first voltage component and the first current component in the dq coordinate system, and the second voltage component and the second current component in the dq coordinate system; Based on the first voltage component and the first current component, determine The power relationship at the first instant in the coordinate system; Based on the second voltage component and the second current component, determine the second instantaneous power relationship in the dq coordinate system; By combining the first instantaneous power relationship and the second instantaneous power relationship, an orthogonal current relationship equation is constructed, and the current value of the β-axis orthogonal current is calculated through the orthogonal current relationship equation. The specific orthogonal current relationship equation is as follows: In the formula, The β-axis orthogonal current, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. For the AC side input voltage at β-axis voltage component in coordinate system This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. This represents the q-axis current component of the AC input current in the dq coordinate system. For the AC side input voltage at Voltage component along the α-axis in the coordinate system.

2. The method for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter according to claim 1, characterized in that, The first instantaneous power relationship is as follows: In the formula, For the AC side input voltage at α-axis voltage component in the coordinate system For the AC side input voltage at β-axis voltage component in coordinate system The β-axis orthogonal current, For AC side input current at The α-axis current component in the coordinate system, P1 is Instantaneous active power in the coordinate system, Q1 is Instantaneous reactive power in the coordinate system.

3. The method for constructing the current of a high-efficiency single-stage bidirectional AC-DC converter according to claim 1, characterized in that, The second instantaneous power relationship is as follows: In the formula, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. P2 represents the q-axis current component of the AC input current in the dq coordinate system, P2 represents the instantaneous active power in the dq coordinate system, and Q2 represents the instantaneous reactive power in the dq coordinate system.

4. A high-efficiency single-stage bidirectional AC-DC converter current configuration device, applied to a single-stage bidirectional AC-DC converter, wherein the single-stage bidirectional AC-DC converter comprises: An LC filter circuit, a matrix transformation circuit, a high-frequency transformer, an LCL resonant circuit, an H-bridge circuit, and an output filter circuit are characterized in that the current-constructing device includes: An electrical signal acquisition unit is used to acquire the AC side input voltage and AC side input current of the single-stage bidirectional AC-DC converter based on the single-stage bidirectional AC-DC converter. The electrical signal component conversion unit is used to convert the AC input voltage and the AC input current into electrical signals respectively through coordinate system transformation. The first voltage component and the first current component in the dq coordinate system, and the second voltage component and the second current component in the dq coordinate system; The first power relationship determination unit is used to determine, based on the first voltage component and the first current component, the following: The power relationship at the first instant in the coordinate system; The second power relationship determination unit is used to determine the second instantaneous power relationship in the dq coordinate system based on the second voltage component and the second current component. The orthogonal current determination unit is used to construct an orthogonal current relationship equation by combining the first instantaneous power relationship equation and the second instantaneous power relationship equation, so as to calculate the current value of the β-axis orthogonal current through the orthogonal current relationship equation; The specific orthogonal current relationship equation is as follows: In the formula, The β-axis orthogonal current, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. For the AC side input voltage at β-axis voltage component in coordinate system This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. This represents the q-axis current component of the AC input current in the dq coordinate system. For the AC side input voltage at Voltage component along the α-axis in the coordinate system.

5. The high-efficiency single-stage bidirectional AC-DC converter current configuration device according to claim 4, characterized in that, The first instantaneous power relationship is as follows: In the formula, For the AC side input voltage at α-axis voltage component in the coordinate system For the AC side input voltage at β-axis voltage component in coordinate system The β-axis orthogonal current, For AC side input current at The α-axis current component in the coordinate system, P1 is Instantaneous active power in the coordinate system, Q1 is Instantaneous reactive power in the coordinate system.

6. The high-efficiency single-stage bidirectional AC-DC converter current configuration device according to claim 4, characterized in that, The second instantaneous power relationship is as follows: In the formula, This represents the d-axis voltage component of the AC input voltage in the dq coordinate system. This represents the d-axis current component of the AC input current in the dq coordinate system. This represents the q-axis voltage component of the AC input voltage in the dq coordinate system. P2 represents the q-axis current component of the AC input current in the dq coordinate system, P2 represents the instantaneous active power in the dq coordinate system, and Q2 represents the instantaneous reactive power in the dq coordinate system.

7. A high-efficiency single-stage bidirectional AC-DC converter current structure termination, characterized in that, include: Memory and processor; The memory is used to store program code, which is used to implement the efficient single-stage bidirectional AC-DC converter current construction method as described in any one of claims 1 to 3; The processor is used to read and execute the program code.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores program code that is read and executed by a processor to implement a high-efficiency single-stage bidirectional AC-DC converter current construction method as described in any one of claims 1 to 3.

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