A single-stage ac-dc converter bidirectional power transmission control method and device

Abstract

This invention relates to the field of electronic converter control technology, specifically providing a method and apparatus for bidirectional power transfer control of a single-stage AC / DC converter. The method includes: determining the modulation phase-shift angle and switching frequency of the single-stage AC / DC converter based on its input voltage; generating a PWM signal based on the phase-shift angle and switching frequency of the single-stage AC / DC converter according to the principle of frequency conversion phase-shift modulation; and using the PWM signal to control the on / off state of the switching devices in the single-stage AC / DC converter. The technical solution provided by this invention, while achieving electrical isolation and bidirectional energy flow in the single-stage AC / DC converter, can significantly reduce system return power, improve overall efficiency, and possesses fast power point tracking capability, good operational robustness, and flexible active / reactive power control functions. It can be widely applied in new energy grid connection, energy storage systems, and electric vehicle charging and discharging, demonstrating clear engineering practical value and promising prospects for promotion.

Description

Technical Field

[0001] This invention relates to the field of electronic converter control technology, specifically to a bidirectional power transmission control method and apparatus for a single-stage AC / DC converter. Background Technology

[0002] With the widespread integration of new energy power generation, energy storage systems, and electric vehicle charging into distribution networks, these networks face multiple power quality issues, including voltage sags, three-phase imbalances, harmonics, and reactive power deficiencies. Modular distribution control equipment integrating energy and information technology, and Unified Power Quality Conditioners (UPQCs), as comprehensive governance devices integrating series and parallel compensation functions, can simultaneously address voltage sags, voltage rises, harmonics, imbalances, and reactive power issues, becoming effective means to improve the power supply quality of distribution networks.

[0003] However, traditional UPQC devices often employ two-stage or multi-stage power conversion structures, with their series and parallel converters typically designed independently. This results in complex system structures, large size, high cost, and low efficiency. Especially during wide-range power regulation, traditional control strategies tend to increase return current power and switching losses, affecting overall system efficiency and dynamic response performance. Furthermore, existing UPQC devices are mostly based on two-level topologies, which, while possessing basic compensation functions, still have significant room for improvement in terms of high power density, high integration, and high-efficiency operation. Summary of the Invention

[0004] To overcome the above-mentioned defects, this invention proposes a bidirectional power transmission control method and device for a single-stage AC / DC converter.

[0005] In a first aspect, a bidirectional power transfer control method for a single-stage AC / DC converter is provided, the single-stage AC / DC converter bidirectional power transfer control method comprising: Determine the modulation phase shift angle and switching frequency of a single-stage AC / DC converter based on its input voltage. Based on the phase shift angle and switching frequency of the single-stage AC / DC converter, a PWM signal is generated according to the frequency conversion phase shift modulation principle. The PWM signal is used to control the on / off state of the switching devices in a single-stage AC / DC converter.

[0006] Preferably, the input voltage of the single-stage AC / DC converter is as follows:

[0007] In the above formula, This is the input voltage of a single-stage AC / DC converter. This represents the effective value of the AC side voltage of a single-stage AC / DC converter. This is the voltage across the filter inductor.

[0008] Furthermore, the voltage across the filter inductor is as follows:

[0009] In the above formula, For filtering inductors, This refers to the DC-side current of a single-stage AC / DC converter. For AC power frequency, This represents the effective value of the DC-side voltage of a single-stage AC / DC converter. This represents the effective value of the DC-side current in a single-stage AC / DC converter. For single-stage AC / DC converter efficiency, For time.

[0010] Furthermore, the efficiency of the single-stage AC / DC converter satisfies:

[0011] In the above formula, This refers to the instantaneous power output of the DC side power supply of a single-stage AC / DC converter. This refers to the instantaneous power output of the AC side power supply of a single-stage AC / DC converter.

[0012] Furthermore, when using frequency conversion single-phase shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0013] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0014] Furthermore, the modulation phase shift angle of the single-stage AC / DC converter is the phase shift angle between the primary and secondary bridges. When the switching frequency of the single-stage AC / DC converter does not exceed the limit and the primary-side return current power is 0, the phase shift angle between the primary and secondary bridges is as follows:

[0015] When the switching frequency of the single-stage AC / DC converter is within the limit and the secondary-side return power is 0, the phase shift angle between the primary and secondary bridges is as follows:

[0016] When the switching frequency of the single-stage AC / DC converter exceeds its upper limit, the switching frequency of the single-stage AC / DC converter is adjusted to its upper limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula:

[0017] When the switching frequency of the single-stage AC / DC converter falls below the lower limit, the switching frequency of the single-stage AC / DC converter is adjusted to its lower limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula:

[0018] In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency of a single-stage AC / DC converter.

[0019] Furthermore, when using frequency conversion extended phase-shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0020] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0021] Furthermore, the modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are as follows:

[0022] When the switching frequency of a single-stage AC / DC converter exceeds the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are equal. The phase shift angle between the primary and secondary bridges is a value less than 0.5, which is either a first intermediate value or a second intermediate value. The first intermediate value and the second intermediate value are as follows:

[0023] In the above formula, The first median value, The second intermediate value, This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

[0024] Furthermore, when using frequency conversion three-phase shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0025] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0026] Furthermore, the modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0027]

[0028] When the switching frequency of a single-stage AC / DC converter exceeds the upper limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0029]

[0030] When the switching frequency of a single-stage AC / DC converter falls below the lower limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0031]

[0032] In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This refers to the phase shift angle within the primary bridge of a single-stage AC / DC converter. This refers to the phase shift angle within the secondary bridge of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

[0033] Secondly, a bidirectional power transmission control device for a single-stage AC / DC converter is provided, the single-stage AC / DC converter bidirectional power transmission control device comprising: The determination module is used to determine the modulation phase shift angle and switching frequency of a single-stage AC / DC converter based on the input voltage of the single-stage AC / DC converter. The generation module is used to generate a PWM signal based on the phase shift angle and switching frequency of the single-stage AC / DC converter, according to the frequency conversion phase shift modulation principle. The control module is used to control the on / off state of the switching devices in the single-stage AC / DC converter using the PWM signal.

[0034] Thirdly, a computer device is provided, comprising: one or more processors; The processor is used to store one or more programs; When the one or more programs are executed by the one or more processors, the bidirectional power transfer control method for a single-stage AC / DC converter is implemented.

[0035] Fourthly, a computer-readable storage medium is provided having a computer program stored thereon, wherein when the computer program is executed, the bidirectional power transfer control method for a single-stage AC / DC converter is implemented.

[0036] The above-described technical solutions of the present invention have at least one or more of the following beneficial effects: This invention provides a method and apparatus for bidirectional power transfer control of a single-stage AC / DC converter, comprising: determining the modulation phase-shift angle and switching frequency of the single-stage AC / DC converter based on the input voltage of the single-stage AC / DC converter; generating a PWM signal based on the phase-shift angle and switching frequency of the single-stage AC / DC converter according to the principle of frequency conversion phase-shift modulation; and using the PWM signal to control the on / off state of the switching devices in the single-stage AC / DC converter. The technical solution provided by this invention, while achieving electrical isolation and bidirectional energy flow in the single-stage AC / DC converter, can significantly reduce system return power, improve overall efficiency, and possesses fast power point tracking capability, good operational robustness, and flexible active / reactive power control functions. It can be widely applied in new energy grid connection, energy storage systems, and electric vehicle charging and discharging, and has clear engineering practical value and promising prospects for promotion. Attached Figure Description

[0037] Figure 1 This is a schematic flowchart of the main steps of the bidirectional power transmission control method for a single-stage AC / DC converter according to an embodiment of the present invention. Detailed Implementation

[0038] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] Example 1 See appendix Figure 1 , Figure 1 This is a schematic flowchart illustrating the main steps of a bidirectional power transfer control method for a single-stage AC / DC converter according to an embodiment of the present invention. Figure 1 As shown, the bidirectional power transfer control method for a single-stage AC / DC converter in this embodiment of the invention mainly includes the following steps: Step S101: Determine the modulation phase shift angle and switching frequency of the single-stage AC / DC converter based on the input voltage of the single-stage AC / DC converter; Step S102: Based on the phase shift angle and switching frequency of the single-stage AC / DC converter, generate a PWM signal according to the frequency conversion phase shift modulation principle; Step S103: Use the PWM signal to control the on / off state of the switching devices in the single-stage AC / DC converter.

[0041] In this embodiment, the input voltage of the single-stage AC / DC converter is as follows:

[0042] In the above formula, This is the input voltage of a single-stage AC / DC converter. This represents the effective value of the AC side voltage of a single-stage AC / DC converter. This is the voltage across the filter inductor.

[0043] In one embodiment, the voltage across the filter inductor is as follows:

[0044] In the above formula, For filtering inductors, This refers to the DC-side current of a single-stage AC / DC converter. For AC power frequency, This represents the effective value of the DC-side voltage of a single-stage AC / DC converter. This represents the effective value of the DC-side current in a single-stage AC / DC converter. For single-stage AC / DC converter efficiency, For time.

[0045] In one embodiment, the efficiency of the single-stage AC / DC converter satisfies:

[0046] In the above formula, This refers to the instantaneous power output of the DC side power supply of a single-stage AC / DC converter. This refers to the instantaneous power output of the AC side power supply of a single-stage AC / DC converter.

[0047] The frequency conversion phase-shift modulation strategy in this embodiment can be selected according to different system requirements for efficiency, complexity, and performance, including frequency conversion single-phase-shift modulation, frequency conversion extended phase-shift modulation, and frequency conversion three-phase-shift modulation. Among them, frequency conversion three-phase-shift modulation, by coordinating the phase shift angle D1 within the primary bridge, the phase shift angle D2 within the secondary bridge, and the phase shift angle D0 between the primary and secondary bridges, can provide the highest degree of control freedom. Under the premise of satisfying power transmission constraints, it can minimize the bilateral return current power across the entire power range, thereby significantly improving system efficiency.

[0048] In one implementation, when using frequency conversion single-phase-shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0049] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0050] In one embodiment, the modulation phase shift angle of the single-stage AC / DC converter is the phase shift angle between the primary and secondary bridges. When the switching frequency of the single-stage AC / DC converter is not exceeded and the primary-side return power is 0, the phase shift angle between the primary and secondary bridges is as follows:

[0051] When the switching frequency of the single-stage AC / DC converter is within the limit and the secondary-side return power is 0, the phase shift angle between the primary and secondary bridges is as follows:

[0052] When the switching frequency of the single-stage AC / DC converter exceeds its upper limit, the switching frequency of the single-stage AC / DC converter is adjusted to its upper limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula:

[0053] When the switching frequency of the single-stage AC / DC converter falls below the lower limit, the switching frequency of the single-stage AC / DC converter is adjusted to its lower limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula:

[0054] In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency of a single-stage AC / DC converter.

[0055] In one implementation, when using frequency conversion extended phase-shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0056] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0057] In one embodiment, the modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are as follows:

[0058] When the switching frequency of a single-stage AC / DC converter exceeds the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are equal. The phase shift angle between the primary and secondary bridges is a value less than 0.5, which is either a first intermediate value or a second intermediate value. The first intermediate value and the second intermediate value are as follows:

[0059] In the above formula, The first median value, The second intermediate value, This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

[0060] In one implementation, when using frequency conversion three-phase shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0061] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0062] In one embodiment, the modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0063]

[0064] When the switching frequency of a single-stage AC / DC converter exceeds the upper limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0065]

[0066] When the switching frequency of a single-stage AC / DC converter falls below the lower limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0067]

[0068] In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This refers to the phase shift angle within the primary bridge of a single-stage AC / DC converter. This refers to the phase shift angle within the secondary bridge of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

[0069] Example 2 Based on the same inventive concept, the present invention also provides a bidirectional power transmission control device for a single-stage AC / DC converter, the single-stage AC / DC converter bidirectional power transmission control device comprising: The determination module is used to determine the modulation phase shift angle and switching frequency of a single-stage AC / DC converter based on the input voltage of the single-stage AC / DC converter. The generation module is used to generate a PWM signal based on the phase shift angle and switching frequency of the single-stage AC / DC converter, according to the frequency conversion phase shift modulation principle. The control module is used to control the on / off state of the switching devices in the single-stage AC / DC converter using the PWM signal.

[0070] Preferably, the input voltage of the single-stage AC / DC converter is as follows:

[0071] In the above formula, This is the input voltage of a single-stage AC / DC converter. This represents the effective value of the AC side voltage of a single-stage AC / DC converter. This is the voltage across the filter inductor.

[0072] Furthermore, the voltage across the filter inductor is as follows:

[0073] In the above formula, For filtering inductors, This refers to the DC-side current of a single-stage AC / DC converter. For AC power frequency, This represents the effective value of the DC-side voltage of a single-stage AC / DC converter. This represents the effective value of the DC-side current in a single-stage AC / DC converter. For single-stage AC / DC converter efficiency, For time.

[0074] Furthermore, the efficiency of the single-stage AC / DC converter satisfies:

[0075] In the above formula, This refers to the instantaneous power output of the DC side power supply of a single-stage AC / DC converter. This refers to the instantaneous power output of the AC side power supply of a single-stage AC / DC converter.

[0076] Furthermore, when using frequency conversion single-phase shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0077] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0078] Furthermore, the modulation phase shift angle of the single-stage AC / DC converter is the phase shift angle between the primary and secondary bridges. When the switching frequency of the single-stage AC / DC converter does not exceed the limit and the primary-side return current power is 0, the phase shift angle between the primary and secondary bridges is as follows:

[0079] When the switching frequency of the single-stage AC / DC converter is within the limit and the secondary-side return power is 0, the phase shift angle between the primary and secondary bridges is as follows:

[0080] When the switching frequency of the single-stage AC / DC converter exceeds its upper limit, the switching frequency of the single-stage AC / DC converter is adjusted to its upper limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula:

[0081] When the switching frequency of the single-stage AC / DC converter falls below the lower limit, the switching frequency of the single-stage AC / DC converter is adjusted to its lower limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula:

[0082] In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency of a single-stage AC / DC converter.

[0083] Furthermore, when using frequency conversion extended phase-shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0084] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0085] Furthermore, the modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are as follows:

[0086] When the switching frequency of a single-stage AC / DC converter exceeds the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are equal. The phase shift angle between the primary and secondary bridges is a value less than 0.5, which is either a first intermediate value or a second intermediate value. The first intermediate value and the second intermediate value are as follows:

[0087] In the above formula, The first median value, The second intermediate value, This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

[0088] Furthermore, when using frequency conversion three-phase shift modulation, the switching frequency of the single-stage AC / DC converter is as follows:

[0089] In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

[0090] Furthermore, the modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0091]

[0092] When the switching frequency of a single-stage AC / DC converter exceeds the upper limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0093]

[0094] When the switching frequency of a single-stage AC / DC converter falls below the lower limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows:

[0095]

[0096] In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This refers to the phase shift angle within the primary bridge of a single-stage AC / DC converter. This refers to the phase shift angle within the secondary bridge of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

[0097] Example 3 Based on the same inventive concept, this invention also provides a computer device, which includes a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to implement corresponding method flows or corresponding functions, thereby realizing the steps of a single-stage AC / DC converter bidirectional power transfer control method in the above embodiments.

[0098] Example 4 Based on the same inventive concept, this invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the bidirectional power transfer control method for a single-stage AC / DC converter in the above embodiments.

[0099] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention 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.

[0100] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It 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 illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0101] 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.

[0102] 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.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A bidirectional power transfer control method for a single-stage AC / DC converter, characterized in that, The method includes: Determine the modulation phase shift angle and switching frequency of a single-stage AC / DC converter based on its input voltage. Based on the phase shift angle and switching frequency of the single-stage AC / DC converter, a PWM signal is generated according to the frequency conversion phase shift modulation principle. The PWM signal is used to control the on / off state of the switching devices in a single-stage AC / DC converter.

2. The method as described in claim 1, characterized in that, The input voltage of the single-stage AC / DC converter is as follows: In the above formula, This is the input voltage of a single-stage AC / DC converter. This represents the effective value of the AC side voltage of a single-stage AC / DC converter. This is the voltage across the filter inductor.

3. The method as described in claim 2, characterized in that, The voltage across the filter inductor is as follows: In the above formula, For filtering inductors, This refers to the DC-side current of a single-stage AC / DC converter. For AC power frequency, This represents the effective value of the DC-side voltage of a single-stage AC / DC converter. This represents the effective value of the DC-side current in a single-stage AC / DC converter. For single-stage AC / DC converter efficiency, For time.

4. The method as described in claim 3, characterized in that, The efficiency of the single-stage AC / DC converter satisfies: In the above formula, This refers to the instantaneous power output of the DC side power supply of a single-stage AC / DC converter. This refers to the instantaneous power output of the AC side power supply of a single-stage AC / DC converter.

5. The method as described in claim 2, characterized in that, When using frequency conversion single-phase shift modulation, the switching frequency of the single-stage AC / DC converter is as follows: In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

6. The method as described in claim 5, characterized in that, The modulation phase shift angle of the single-stage AC / DC converter is the phase shift angle between the primary and secondary bridges. When the switching frequency of the single-stage AC / DC converter is not exceeded and the primary-side return power is 0, the phase shift angle between the primary and secondary bridges is as follows: When the switching frequency of the single-stage AC / DC converter is within the limit and the secondary-side return power is 0, the phase shift angle between the primary and secondary bridges is as follows: When the switching frequency of the single-stage AC / DC converter exceeds its upper limit, the switching frequency of the single-stage AC / DC converter is adjusted to its upper limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula: When the switching frequency of the single-stage AC / DC converter falls below the lower limit, the switching frequency of the single-stage AC / DC converter is adjusted to its lower limit value, and the phase shift angle between the primary and secondary bridges is determined by the following formula: In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency of a single-stage AC / DC converter.

7. The method as described in claim 2, characterized in that, When frequency conversion extended phase-shift modulation is used, the switching frequency of the single-stage AC / DC converter is as follows: In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

8. The method as described in claim 7, characterized in that, The modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are as follows: When the switching frequency of a single-stage AC / DC converter exceeds the limit, the phase shift angle between the primary and secondary bridges and the phase shift angle within the primary bridge are equal. The phase shift angle between the primary and secondary bridges is a value less than 0.5, which is either a first intermediate value or a second intermediate value. The first intermediate value and the second intermediate value are as follows: In the above formula, The first median value, The second intermediate value, This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

9. The method as described in claim 2, characterized in that, When using frequency conversion three-phase shift modulation, the switching frequency of the single-stage AC / DC converter is as follows: In the above formula, The switching frequency of a single-stage AC / DC converter. It is the voltage ratio. For a single-stage AC / DC converter, the branch series inductor, For transformer turns ratio, This is the input voltage of a single-stage AC / DC converter. This refers to the grid-connected output current of a single-stage AC / DC converter.

10. The method as described in claim 8, characterized in that, The modulation phase shift angle of the single-stage AC / DC converter includes the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge. When the switching frequency of the single-stage AC / DC converter does not exceed the limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows: When the switching frequency of a single-stage AC / DC converter exceeds the upper limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows: When the switching frequency of a single-stage AC / DC converter falls below the lower limit, the phase shift angle between the primary and secondary bridges, the phase shift angle within the primary bridge, and the phase shift angle within the secondary bridge are as follows: In the above formula, This refers to the phase shift angle between the primary and secondary bridges of a single-stage AC / DC converter. This refers to the phase shift angle within the primary bridge of a single-stage AC / DC converter. This refers to the phase shift angle within the secondary bridge of a single-stage AC / DC converter. This represents the upper limit of the switching frequency for a single-stage AC / DC converter. This is the lower limit of the switching frequency for a single-stage AC / DC converter.

11. A bidirectional power transmission control device for a single-stage AC / DC converter, characterized in that, The device includes: The determination module is used to determine the modulation phase shift angle and switching frequency of a single-stage AC / DC converter based on the input voltage of the single-stage AC / DC converter. The generation module is used to generate a PWM signal based on the phase shift angle and switching frequency of the single-stage AC / DC converter, according to the frequency conversion phase shift modulation principle. The control module is used to control the on / off state of the switching devices in the single-stage AC / DC converter using the PWM signal.

12. A computer device, characterized in that, include: One or more processors; The processor is used to execute one or more programs; When the one or more programs are executed by the one or more processors, the bidirectional power transfer control method for a single-stage AC / DC converter as described in any one of claims 1 to 10 is implemented.

13. A computer-readable storage medium, characterized in that, It contains a computer program, which, when executed, implements the bidirectional power transfer control method for a single-stage AC / DC converter as described in any one of claims 1 to 10.

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