Bidirectional energy storage converter

Abstract

The utility model discloses a bidirectional energy storage converter, which adopts a topological structure of a dual-active bridge direct current converter, the structure comprises a high-voltage side two-level full-bridge module, a filtering voltage reduction module and a low-voltage side full-bridge synchronous rectification module, and the high-voltage side two-level full-bridge module supports a wide input voltage range; the low-voltage side full-bridge synchronous rectification module adapts to voltage registration of a battery and a super capacitor, and a filtering voltage reduction module serving as an intermediate stage realizes soft switching (ZVS / ZCS), so that the switching loss during high-frequency work is effectively reduced, and the conversion efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of power electronic conversion technology, and in particular to a bidirectional energy storage converter that can realize bidirectional and efficient energy flow, and is suitable for scenarios such as batteries, supercapacitors, and flywheel energy storage. Background Technology

[0002] With the widespread adoption of renewable energy generation and distributed energy storage systems, bidirectional energy storage converters have become core equipment for energy management. Traditional bidirectional converters often employ phase-shifted full-bridge or Buck-Boost topologies, which suffer from high switching losses, slow dynamic response, high size and cost, and insufficient protection capabilities. High switching losses are due to the hard-switching mode used in traditional bidirectional converters, which generates significant switching losses at high frequencies, leading to efficiency degradation. Slow dynamic response is caused by the slow response speed of traditional phase-shifted control strategies, making them unable to quickly respond to sudden load changes. High size and cost are due to the need for numerous magnetic components and power devices in multi-stage circuit designs, resulting in a large overall size, complex circuit structure, and high cost. Insufficient protection capabilities stem from the lack of rapid fault isolation mechanisms in traditional bidirectional converters, making them prone to device damage in the event of overcurrent or short circuits. Furthermore, the narrow input voltage range of existing bidirectional energy storage converters makes them difficult to adapt to energy storage systems with different voltage levels, limiting their applicability. Summary of the Invention

[0003] This utility model provides a bidirectional energy storage converter to solve the problems of narrow input voltage range and large switching losses in existing bidirectional energy storage converters.

[0004] In one embodiment, a bidirectional energy storage converter is provided, the bidirectional energy storage converter comprising:

[0005] The system comprises a high-voltage side two-level full-bridge module, a filter and step-down module, a low-voltage side full-bridge synchronous rectification module, and a bidirectional rectification and inverter module. The input terminal of the high-voltage side two-level full-bridge module is used to input a preset high-voltage AC signal. The output terminal of the high-voltage side two-level full-bridge module is connected to the input terminal of the filter and step-down module. The output terminal of the filter and step-down module is connected to the input terminal of the low-voltage side full-bridge synchronous rectification module. The output terminal of the low-voltage side full-bridge synchronous rectification module is connected to the input terminal of the bidirectional rectification and inverter module. The output terminal of the bidirectional rectification and inverter module is used to output an inverter signal.

[0006] The high-voltage side two-level full-bridge module is used to send the high-voltage AC signal to the filtering and step-down module. The filtering and step-down module is used to step down and filter the high-voltage AC signal to obtain a low-voltage AC signal. The low-voltage side full-bridge synchronous rectification module is used to rectify the low-voltage AC signal to obtain a low-voltage rectified signal. The bidirectional rectification and inverter module is used to invert the low-voltage rectified signal to obtain a low-voltage inverter signal.

[0007] In one embodiment, the high-voltage side two-level full-bridge module includes:

[0008] The system comprises a first upper bridge arm power switch, a first lower bridge arm power switch, a second upper bridge arm power switch, and a second lower bridge arm power switch. The input terminal of the first upper bridge arm power switch is connected to the positive terminal of an external signal source, the output terminal of the first upper bridge arm power switch is connected to the input terminal of the first lower bridge arm power switch, and the output terminal of the first lower bridge arm power switch is connected to the negative terminal of the external signal source.

[0009] The input terminal of the second upper bridge arm power switch is connected to the positive terminal of the external signal source, the output terminal of the second upper bridge arm power switch is connected to the input terminal of the second lower bridge arm power switch, and the output terminal of the second lower bridge arm power switch is connected to the negative terminal of the external signal source.

[0010] The series connection between the first upper bridge arm power switch and the first lower bridge arm power switch leads to the first output terminal of the high-voltage side two-level full-bridge module, and the series connection between the second upper bridge arm power switch and the second lower bridge arm power switch leads to the second output terminal of the high-voltage side two-level full-bridge module.

[0011] In one embodiment, the filtering and buckling module includes:

[0012] The system includes a transformer, a first filter inductor, and a first filter capacitor. The first input terminal of the primary side of the transformer is connected to the first output terminal of the high-voltage side two-level full-bridge module, the second input terminal of the primary side of the transformer is connected to the second output terminal of the high-voltage side two-level full-bridge module, the first output terminal of the secondary side of the transformer is connected to the input terminal of the first filter inductor, the output terminal of the first filter inductor is connected to the input terminal of the first filter capacitor, the output terminal of the first filter capacitor serves as the first output terminal of the filter step-down module, and the second output terminal of the secondary side of the transformer serves as the second output terminal of the filter step-down module.

[0013] In one embodiment, the low-voltage side full-bridge synchronous rectification module includes:

[0014] The third upper bridge arm power switch, the third lower bridge arm power switch, the fourth upper bridge arm power switch, and the fourth lower bridge arm power switch are connected. The input terminal of the third upper bridge arm power switch is connected to the first output terminal of the filter step-down module. The output terminal of the third upper bridge arm power switch serves as the positive output terminal of the low-voltage side full-bridge synchronous rectification module. The input terminal of the third lower bridge arm power switch is connected to the input terminal of the third upper bridge arm power switch. The output terminal of the third lower bridge arm power switch serves as the negative output terminal of the low-voltage side full-bridge synchronous rectification module.

[0015] The input terminal of the fourth upper bridge arm power switch is connected to the second output terminal of the filter step-down module, the output terminal of the fourth upper bridge arm power switch is connected to the output terminal of the third upper bridge arm power switch, the input terminal of the fourth lower bridge arm power switch is connected to the input terminal of the fourth upper bridge arm power switch, and the output terminal of the fourth lower bridge arm power switch is connected to the output terminal of the third lower bridge arm power switch.

[0016] In one embodiment, the bidirectional rectifier-inverter module includes:

[0017] The fifth upper bridge arm power switch, the fifth lower bridge arm power switch, the sixth upper bridge arm power switch, and the sixth lower bridge arm power switch are connected. The input terminal of the fifth upper bridge arm power switch is connected to the positive output terminal of the low-voltage side full-bridge synchronous rectification module, the output terminal of the fifth upper bridge arm power switch is connected to the input terminal of the fifth lower bridge arm power switch, and the output terminal of the fifth lower bridge arm power switch is connected to the negative output terminal of the low-voltage side full-bridge synchronous rectification module.

[0018] The input terminal of the sixth upper bridge arm power switch is connected to the positive output terminal of the low-voltage side full-bridge synchronous rectification module, the output terminal of the sixth upper bridge arm power switch is connected to the input terminal of the sixth lower bridge arm power switch, and the output terminal of the sixth lower bridge arm power switch is connected to the negative output terminal of the low-voltage side full-bridge synchronous rectification module.

[0019] The series connection between the fifth upper bridge arm power switch and the fifth lower bridge arm power switch leads to the first output terminal of the bidirectional rectifier inverter module, and the series connection between the sixth upper bridge arm power switch and the sixth lower bridge arm power switch leads to the second output terminal of the bidirectional rectifier inverter module.

[0020] In one embodiment, the bidirectional energy storage converter further includes:

[0021] The second filter inductor and the second filter capacitor are connected as follows: the input terminal of the second filter inductor is connected to the first output terminal of the bidirectional rectifier inverter module; the output terminal of the second filter inductor is connected to the input terminal of the second filter capacitor and the positive terminal of the external load; and the output terminal of the second filter capacitor is connected to the second output terminal of the bidirectional rectifier inverter module and the negative terminal of the external load.

[0022] In one embodiment, the bidirectional energy storage converter further includes:

[0023] The first voltage regulator module has its positive terminal connected to the positive output terminal of the low-voltage side full-bridge synchronous rectifier module, and its negative terminal connected to the negative output terminal of the low-voltage side full-bridge synchronous rectifier module.

[0024] In one embodiment, the first voltage regulator module includes:

[0025] A first voltage-regulating capacitor, a second voltage-regulating capacitor, and a third voltage-regulating capacitor are provided. The first voltage-regulating capacitor and the second voltage-regulating capacitor are connected in parallel, and the second voltage-regulating capacitor and the third voltage-regulating capacitor are connected in parallel.

[0026] In one embodiment, the bidirectional energy storage converter further includes:

[0027] The positive terminal of the second voltage regulator module is connected to the input terminal of the first upper bridge arm power switch, and the negative terminal of the second voltage regulator module is connected to the output terminal of the first lower bridge arm power switch.

[0028] In one embodiment, the second voltage regulator module includes:

[0029] A fourth voltage-regulating capacitor and a fifth voltage-regulating capacitor are connected in series.

[0030] This utility model provides a bidirectional energy storage converter, which adopts a dual active bridge DC-DC converter topology. This structure includes a high-voltage side two-level full-bridge module, a filter and step-down module, and a low-voltage side full-bridge synchronous rectification module. The high-voltage side two-level full-bridge module supports a wide input voltage range; the low-voltage side full-bridge synchronous rectification module is adapted to the voltage registration of batteries and supercapacitors; and the filter and step-down module, as an intermediate stage, implements soft switching (ZVS / ZCS), which effectively reduces switching losses during high-frequency operation and thus improves conversion efficiency. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a circuit diagram of a bidirectional energy storage converter in one embodiment of the present invention. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0034] It should be understood that this invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art. In the drawings, for clarity, the dimensions of layers and regions, as well as their relative dimensions, may be exaggerated. The same reference numerals denote the same elements throughout.

[0035] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this utility model, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0036] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0037] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0038] To fully understand this utility model, detailed structures and steps will be presented in the following description to illustrate the technical solution proposed by this utility model. Preferred embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.

[0039] In one embodiment, such as Figure 1 As shown, a bidirectional energy storage converter is provided, the bidirectional energy storage converter comprising:

[0040] The system comprises a high-voltage side two-level full-bridge module 10, a filter and step-down module 20, a low-voltage side full-bridge synchronous rectification module 30, and a bidirectional rectification and inverter module 40. The input terminal of the high-voltage side two-level full-bridge module 10 is used to input a preset high-voltage AC signal. The output terminal of the high-voltage side two-level full-bridge module 10 is connected to the input terminal of the filter and step-down module 20. The output terminal of the filter and step-down module 20 is connected to the input terminal of the low-voltage side full-bridge synchronous rectification module 30. The output terminal of the low-voltage side full-bridge synchronous rectification module 30 is connected to the input terminal of the bidirectional rectification and inverter module 40. The output terminal of the bidirectional rectification and inverter module 40 is used to output an inverter signal.

[0041] The high-voltage side two-level full-bridge module 10 is used to send the high-voltage AC signal to the filtering and step-down module 20. The filtering and step-down module 20 is used to step down and filter the high-voltage AC signal to obtain a low-voltage AC signal. The low-voltage side full-bridge synchronous rectification module 30 is used to rectify the low-voltage AC signal to obtain a low-voltage rectified signal. The bidirectional rectification and inverter module 40 is used to invert the low-voltage rectified signal to obtain a low-voltage inverter signal.

[0042] Among them, the high-voltage side two-level full-bridge module 10 utilizes the ultra-wide bandgap characteristics of SiC devices (capable of withstanding greater current and voltage) to achieve a wide input voltage range, improve voltage utilization, and ultimately simplify peripheral components; the low-voltage side full-bridge synchronous rectification module 30 adopts a full-bridge structure of ordinary SiC devices, enabling bidirectional power transfer, and the synchronous rectification technology reduces conduction losses and improves efficiency; the filter and step-down module 20 achieves soft switching (ZVS / ZCS) of the switching transistor through the phase-shifting principle, effectively reducing high-frequency switching losses and improving efficiency.

[0043] The bidirectional energy storage converter in this embodiment adopts a dual active bridge DC-DC converter topology, which includes a high-voltage side two-level full-bridge module 10, a filter and step-down module 20, and a low-voltage side full-bridge synchronous rectification module 30. The high-voltage side two-level full-bridge module 10 supports a wide input voltage range (200V-800V); the low-voltage side full-bridge synchronous rectification module 30 is adapted to batteries / supercapacitors (48V-400V); and the filter and step-down module 20, as an intermediate stage, implements soft switching (ZVS / ZCS), effectively reducing switching losses during high-frequency operation and thus improving conversion efficiency. Therefore, the topology of the bidirectional energy storage converter in this embodiment has advantages such as flexible input / output voltage matching, bidirectional power transfer, and high efficiency.

[0044] In one embodiment, such as Figure 1 As shown, the high-voltage side two-level full-bridge module 10 includes:

[0045] The first upper arm power switch S1, the first lower arm power switch S2, the second upper arm power switch S3, and the second lower arm power switch S4 are connected. The input terminal of the first upper arm power switch S1 is connected to the positive terminal of an external signal source, the output terminal of the first upper arm power switch S1 is connected to the input terminal of the first lower arm power switch S2, and the output terminal of the first lower arm power switch S2 is connected to the negative terminal of the external signal source.

[0046] The input terminal of the second upper bridge arm power switch S3 is connected to the positive terminal of the external signal source, the output terminal of the second upper bridge arm power switch S3 is connected to the input terminal of the second lower bridge arm power switch S4, and the output terminal of the second lower bridge arm power switch S4 is connected to the negative terminal of the external signal source.

[0047] The series connection between the first upper bridge arm power switch S1 and the first lower bridge arm power switch S2 leads to the first output terminal of the high-voltage side two-level full-bridge module 10, and the series connection between the second upper bridge arm power switch S3 and the second lower bridge arm power switch S4 leads to the second output terminal of the high-voltage side two-level full-bridge module 10.

[0048] Among them, the power switching transistors S1, S2, S3, and S4 are model C3M0040120K, with a rated voltage of 1200V and a rated current of 66A.

[0049] In this embodiment, the four power switches S1, S2, S3, and S4 employ a full-bridge structure to achieve bidirectional power transfer. This structure supports a wide input voltage range of 200V-800V Vin, making it suitable for energy storage systems with different voltage levels.

[0050] In one embodiment, such as Figure 1 As shown, the filter and step-down module 20 includes:

[0051] The system comprises a transformer T1, a first filter inductor Lr, and a first filter capacitor Cr. The primary winding of transformer T1 has its first input terminal connected to the first output terminal of the high-voltage side two-level full-bridge module 10. The primary winding of transformer T1 has its second input terminal connected to the second output terminal of the high-voltage side two-level full-bridge module 10. The secondary winding of transformer T1 has its first output terminal connected to the input terminal of the first filter inductor Lr. The output terminal of the first filter inductor Lr is connected to the input terminal of the first filter capacitor Cr. The output terminal of the first filter capacitor Cr serves as the first output terminal of the filter step-down module 20, and the secondary winding of transformer T1 serves as the second output terminal of the filter step-down module 20. For example, the inductor Lr is 60uH, the capacitor Cr is 2.2nF, and the transformer T1 consists of three EE42 type transformers connected in parallel, with 16 primary turns, 12 secondary turns, and a leakage inductance of 20uH.

[0052] In this circuit, the inductor Lr and capacitor Cr form an LC network, which achieves soft switching (ZVS / ZCS) of the switching transistor through the phase-shifting principle, effectively reducing high-frequency switching losses. The high-voltage side of transformer T1 is connected to the high-voltage side two-level full-bridge module 10, and the low-voltage side is connected to the low-voltage side full-bridge synchronous rectification module 30, realizing the transfer of electrical energy between the high and low voltage sides.

[0053] In one embodiment, such as Figure 1 As shown, the low-voltage side full-bridge synchronous rectification module 30 includes:

[0054] The third upper arm power switch Q1, the third lower arm power switch Q2, the fourth upper arm power switch Q3, and the fourth lower arm power switch Q4 are connected. The input terminal of the third upper arm power switch Q1 is connected to the first output terminal of the filter step-down module 20, and the output terminal of the third upper arm power switch Q1 serves as the positive output terminal of the low-voltage side full-bridge synchronous rectification module 30. The input terminal of the third lower arm power switch Q2 is connected to the input terminal of the third upper arm power switch Q1, and the output terminal of the third lower arm power switch Q2 serves as the negative output terminal of the low-voltage side full-bridge synchronous rectification module 30.

[0055] The input terminal of the fourth upper bridge arm power switch Q3 is connected to the second output terminal of the filter step-down module 20. The output terminal of the fourth upper bridge arm power switch Q3 is connected to the output terminal of the third upper bridge arm power switch Q1. The input terminal of the fourth lower bridge arm power switch Q4 is connected to the input terminal of the fourth upper bridge arm power switch Q3. The output terminal of the fourth lower bridge arm power switch Q4 is connected to the output terminal of the third lower bridge arm power switch Q2.

[0056] Among them, the power switching transistors Q1, Q2, Q3, and Q4 are model IPW65R041CFD, with a rated voltage of 650V and a rated current of 68.5A.

[0057] In this embodiment, the four power switching transistors Q1, Q2, Q3, and Q4 adopt a full-bridge structure to achieve bidirectional power transfer. Synchronous rectification technology reduces conduction losses and is compatible with a battery / supercapacitor voltage range of 48V-400V Vout.

[0058] In one embodiment, such as Figure 1 As shown, the bidirectional rectifier-inverter module 40 includes:

[0059] The fifth upper bridge arm power switch Q5, the fifth lower bridge arm power switch Q6, the sixth upper bridge arm power switch Q7, and the sixth lower bridge arm power switch Q7 are connected. The input terminal of the fifth upper bridge arm power switch Q5 is connected to the positive output terminal of the low-voltage side full-bridge synchronous rectification module 30, the output terminal of the fifth upper bridge arm power switch Q5 is connected to the input terminal of the fifth lower bridge arm power switch Q6, and the output terminal of the fifth lower bridge arm power switch Q6 is connected to the negative output terminal of the low-voltage side full-bridge synchronous rectification module 30.

[0060] The input terminal of the sixth upper bridge arm power switch Q7 is connected to the positive output terminal of the low-voltage side full-bridge synchronous rectification module 30, the output terminal of the sixth upper bridge arm power switch Q7 is connected to the input terminal of the sixth lower bridge arm power switch Q7, and the output terminal of the sixth lower bridge arm power switch Q7 is connected to the negative output terminal of the low-voltage side full-bridge synchronous rectification module 30.

[0061] The series connection between the fifth upper arm power switch Q5 and the fifth lower arm power switch Q6 leads to the first output terminal of the bidirectional rectifier inverter module 40, and the series connection between the sixth upper arm power switch Q7 and the sixth lower arm power switch Q7 leads to the second output terminal of the bidirectional rectifier inverter module 40.

[0062] The four power switches Q5, Q6, Q7, and Q8 employ a totem-style bridgeless structure to achieve bidirectional rectification and inversion. MOS / IGBTs are used instead of diodes to reduce conduction losses and achieve highly efficient rectification and inversion. L1 and C3 form an LC filter network, primarily to eliminate high-frequency noise in the inverter AC signal.

[0063] In this embodiment, a controller for controlling the bidirectional energy storage converter is also provided. For example, a TMS320C28x DSP with a main frequency of 200MHz is used, featuring a CLA core and FPU independent of the main CPU. Because the controller adopts a dual-core DSP architecture ( Figure 1 The controller, comprising DSP1 and DSP2, achieves microsecond-level response speeds. It dynamically adjusts the resonant frequency and duty cycle based on the operating mode (charging / discharging / standby) and optimizes the phase shift angle based on real-time current sampling feedback, thereby improving overall efficiency. Furthermore, the controller implements a rapid fault isolation mechanism, enabling timely circuit disconnection in the event of overcurrent or short circuit, effectively protecting components from damage.

[0064] In one embodiment, such as Figure 1 As shown, the bidirectional energy storage converter further includes:

[0065] The second filter inductor L and the second filter capacitor C3 are connected as follows: the input terminal of the second filter inductor L is connected to the first output terminal of the bidirectional rectifier inverter module 40; the output terminal of the second filter inductor L is connected to the input terminal of the second filter capacitor C3 and the positive terminal of the external load; and the output terminal of the second filter capacitor C3 is connected to the second output terminal of the bidirectional rectifier inverter module 40 and the negative terminal of the external load.

[0066] In one embodiment, such as Figure 1 As shown, the bidirectional energy storage converter further includes:

[0067] The first voltage regulator module has its positive terminal connected to the positive output terminal of the low-voltage side full-bridge synchronous rectification module 30, and its negative terminal connected to the negative output terminal of the low-voltage side full-bridge synchronous rectification module 30.

[0068] In one embodiment, such as Figure 1 As shown, the first voltage regulator module includes:

[0069] The system comprises a first voltage-regulating capacitor C21, a second voltage-regulating capacitor C22, and a third voltage-regulating capacitor C23. The first voltage-regulating capacitor C21 and the second voltage-regulating capacitor C22 are connected in parallel, and the second voltage-regulating capacitor C22 and the third voltage-regulating capacitor C23 are connected in parallel. For example, capacitors C21, C22, and C23 all have a capacitance of 390uF and a rated voltage of 450V.

[0070] In one embodiment, such as Figure 1 As shown, the bidirectional energy storage converter further includes:

[0071] The second voltage regulator module has its positive terminal connected to the input terminal of the first upper bridge arm power switch S1, and its negative terminal connected to the output terminal of the first lower bridge arm power switch S2.

[0072] In one embodiment, such as Figure 1 As shown, the second voltage regulator module includes:

[0073] The fourth voltage regulator capacitor C11 and the fifth voltage regulator capacitor C12 are connected in series. For example, both capacitors C11 and C12 have a capacitance of 180uF and a rated voltage of 450V.

[0074] In this embodiment, the bidirectional energy storage converter has a rated power of 6.6kW, an input voltage range of 300V-800V, an output voltage range of 200V-350V, and a maximum efficiency of 98.5%. At rated power, the overall volume is less than 5L, and the power density is as high as 2kW / L.

[0075] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model 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 utility model, and should all be included within the protection scope of this utility model.

Claims

1. A bidirectional energy storage converter, characterized in that, The bidirectional energy storage converter includes: The system comprises a high-voltage side two-level full-bridge module, a filter and step-down module, a low-voltage side full-bridge synchronous rectification module, and a bidirectional rectification and inverter module. The input terminal of the high-voltage side two-level full-bridge module is used to input a preset high-voltage AC signal. The output terminal of the high-voltage side two-level full-bridge module is connected to the input terminal of the filter and step-down module. The output terminal of the filter and step-down module is connected to the input terminal of the low-voltage side full-bridge synchronous rectification module. The output terminal of the low-voltage side full-bridge synchronous rectification module is connected to the input terminal of the bidirectional rectification and inverter module. The output terminal of the bidirectional rectification and inverter module is used to output an inverter signal. The high-voltage side two-level full-bridge module is used to send the high-voltage AC signal to the filtering and step-down module. The filtering and step-down module is used to step down and filter the high-voltage AC signal to obtain a low-voltage AC signal. The low-voltage side full-bridge synchronous rectification module is used to rectify the low-voltage AC signal to obtain a low-voltage rectified signal. The bidirectional rectification and inverter module is used to invert the low-voltage rectified signal to obtain a low-voltage inverter signal.

2. The bidirectional energy storage converter according to claim 1, characterized in that, The high-voltage side two-level full-bridge module includes: The system comprises a first upper bridge arm power switch, a first lower bridge arm power switch, a second upper bridge arm power switch, and a second lower bridge arm power switch. The input terminal of the first upper bridge arm power switch is connected to the positive terminal of an external signal source, the output terminal of the first upper bridge arm power switch is connected to the input terminal of the first lower bridge arm power switch, and the output terminal of the first lower bridge arm power switch is connected to the negative terminal of the external signal source. The input terminal of the second upper bridge arm power switch is connected to the positive terminal of the external signal source, the output terminal of the second upper bridge arm power switch is connected to the input terminal of the second lower bridge arm power switch, and the output terminal of the second lower bridge arm power switch is connected to the negative terminal of the external signal source. The series connection between the first upper bridge arm power switch and the first lower bridge arm power switch leads to the first output terminal of the high-voltage side two-level full-bridge module, and the series connection between the second upper bridge arm power switch and the second lower bridge arm power switch leads to the second output terminal of the high-voltage side two-level full-bridge module.

3. The bidirectional energy storage converter according to claim 2, characterized in that, The filtering and voltage reduction module includes: The system includes a transformer, a first filter inductor, and a first filter capacitor. The first input terminal of the primary side of the transformer is connected to the first output terminal of the high-voltage side two-level full-bridge module, the second input terminal of the primary side of the transformer is connected to the second output terminal of the high-voltage side two-level full-bridge module, the first output terminal of the secondary side of the transformer is connected to the input terminal of the first filter inductor, the output terminal of the first filter inductor is connected to the input terminal of the first filter capacitor, the output terminal of the first filter capacitor serves as the first output terminal of the filter step-down module, and the second output terminal of the secondary side of the transformer serves as the second output terminal of the filter step-down module.

4. The bidirectional energy storage converter according to claim 3, characterized in that, The low-voltage side full-bridge synchronous rectification module includes: The third upper bridge arm power switch, the third lower bridge arm power switch, the fourth upper bridge arm power switch, and the fourth lower bridge arm power switch are connected. The input terminal of the third upper bridge arm power switch is connected to the first output terminal of the filter step-down module. The output terminal of the third upper bridge arm power switch serves as the positive output terminal of the low-voltage side full-bridge synchronous rectification module. The input terminal of the third lower bridge arm power switch is connected to the input terminal of the third upper bridge arm power switch. The output terminal of the third lower bridge arm power switch serves as the negative output terminal of the low-voltage side full-bridge synchronous rectification module. The input terminal of the fourth upper bridge arm power switch is connected to the second output terminal of the filter step-down module, the output terminal of the fourth upper bridge arm power switch is connected to the output terminal of the third upper bridge arm power switch, the input terminal of the fourth lower bridge arm power switch is connected to the input terminal of the fourth upper bridge arm power switch, and the output terminal of the fourth lower bridge arm power switch is connected to the output terminal of the third lower bridge arm power switch.

5. The bidirectional energy storage converter according to claim 4, characterized in that, The bidirectional rectifier-inverter module includes: The fifth upper bridge arm power switch, the fifth lower bridge arm power switch, the sixth upper bridge arm power switch, and the sixth lower bridge arm power switch are connected. The input terminal of the fifth upper bridge arm power switch is connected to the positive output terminal of the low-voltage side full-bridge synchronous rectification module, the output terminal of the fifth upper bridge arm power switch is connected to the input terminal of the fifth lower bridge arm power switch, and the output terminal of the fifth lower bridge arm power switch is connected to the negative output terminal of the low-voltage side full-bridge synchronous rectification module. The input terminal of the sixth upper bridge arm power switch is connected to the positive output terminal of the low-voltage side full-bridge synchronous rectification module, the output terminal of the sixth upper bridge arm power switch is connected to the input terminal of the sixth lower bridge arm power switch, and the output terminal of the sixth lower bridge arm power switch is connected to the negative output terminal of the low-voltage side full-bridge synchronous rectification module. The series connection between the fifth upper bridge arm power switch and the fifth lower bridge arm power switch leads to the first output terminal of the bidirectional rectifier inverter module, and the series connection between the sixth upper bridge arm power switch and the sixth lower bridge arm power switch leads to the second output terminal of the bidirectional rectifier inverter module.

6. The bidirectional energy storage converter according to claim 5, characterized in that, The bidirectional energy storage converter also includes: The second filter inductor and the second filter capacitor are connected as follows: the input terminal of the second filter inductor is connected to the first output terminal of the bidirectional rectifier inverter module; the output terminal of the second filter inductor is connected to the input terminal of the second filter capacitor and the positive terminal of the external load; and the output terminal of the second filter capacitor is connected to the second output terminal of the bidirectional rectifier inverter module and the negative terminal of the external load.

7. The bidirectional energy storage converter according to claim 4 or 5, characterized in that, The bidirectional energy storage converter also includes: The first voltage regulator module has its positive terminal connected to the positive output terminal of the low-voltage side full-bridge synchronous rectifier module, and its negative terminal connected to the negative output terminal of the low-voltage side full-bridge synchronous rectifier module.

8. The bidirectional energy storage converter according to claim 7, characterized in that, The first voltage regulator module includes: A first voltage-regulating capacitor, a second voltage-regulating capacitor, and a third voltage-regulating capacitor are provided. The first voltage-regulating capacitor and the second voltage-regulating capacitor are connected in parallel, and the second voltage-regulating capacitor and the third voltage-regulating capacitor are connected in parallel.

9. The bidirectional energy storage converter according to claim 2, characterized in that, The bidirectional energy storage converter also includes: The positive terminal of the second voltage regulator module is connected to the input terminal of the first upper bridge arm power switch, and the negative terminal of the second voltage regulator module is connected to the output terminal of the first lower bridge arm power switch.

10. The bidirectional energy storage converter according to claim 9, characterized in that, The second voltage regulator module includes: A fourth voltage-regulating capacitor and a fifth voltage-regulating capacitor are connected in series.

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