Converter power supply device based on frequency interval hysteresis control and power supply method thereof

Abstract

This invention provides a converter power supply device and method based on frequency range hysteresis control. The device includes at least two converters, at least two transformers, a first switch, and a second switch. Each converter includes two inverters. The secondary sides of the transformers are connected in series and then in series with the load to form a loop. The primary sides of the transformers are connected to one converter. The first terminal of the primary side of each transformer is connected to one inverter in the corresponding transformer, and the second terminal is connected to the other inverter in the corresponding transformer. The first terminal of the first switch is connected to the middle of the primary side of the first transformer, and the second terminal is connected to the second terminal of the second switch. The first terminal of the second switch is connected to the second terminal of the first transformer, and the second terminal is connected to the first terminal of the second transformer. In inductor mode, the first switch is closed and the second switch is open. In transformer mode with cascaded secondary transformers, the first switch is open and the second switch is closed.

Description

Technical Field

[0001] This invention relates to the field of converter power supply technology, and in particular to a converter power supply device and power supply method based on frequency range hysteresis control. Background Technology

[0002] Application issues of multiple converters: To achieve high-power, high-capacity converter output power, after the development of various converter topologies, application cases of multiple converters connected in series, parallel, and cascaded have emerged. Since the connection relationship of multiple converters is based on the condition that all converters are fault-free, if one converter fails, one of them needs to be disconnected; or, depending on the switch connection relationship, different operating modes need to be switched, which raises the issue of safe switching between different operating modes. Currently, the switching process between different operating modes is controlled by single-node conditions, which is prone to safety hazards. Summary of the Invention

[0003] This invention provides a converter power supply device and power supply method based on frequency range hysteresis control, which can solve the technical problem of safety hazards in the switching process of different operating modes in the prior art.

[0004] According to one aspect of the present invention, a converter power supply device based on frequency range hysteresis control is provided. The device includes at least two converters, at least two transformers, a first switch and a second switch. The number of converters is the same as the number of transformers, and each converter includes two inverters.

[0005] The secondary sides of all transformers are connected in series and then connected in series with the load to form a circuit. The first end of the load is connected to the first end of the secondary side of the first transformer, and the second end of the load is connected to the second end of the secondary side of the last transformer. The primary sides of all transformers are connected to a converter. The first end of the primary side of each transformer is connected to one inverter in the corresponding transformer, and the second end is connected to another inverter in the corresponding transformer.

[0006] The first end of the first switch is connected to the middle of the primary side of the first transformer, and the second end is connected to the second end of the second switch;

[0007] The second switch is connected in series between the secondary side of the first transformer and the secondary side of the second transformer. The first end of the second switch is connected to the second end of the first transformer, and the second end is connected to the first end of the second transformer.

[0008] In inductor mode, the first switch is closed and the second switch is open; in transformer mode with cascaded secondary transformers, the first switch is open and the second switch is closed.

[0009] Preferably, the operating frequency range of the inductor mode is (0~y2)Hz, and the operating frequency range of the transformer mode is greater than (y1)Hz, and y1≤y2.

[0010] According to another aspect of the present invention, a power supply method for a converter power supply device based on frequency range hysteresis control is provided, the method employing any of the aforementioned devices for power supply, the method comprising:

[0011] Determine the current operating mode;

[0012] If the current operating mode is inductor mode, determine whether the current operating frequency is greater than (y2) Hz. If so, determine that the operating mode for the next moment is transformer mode, open the first switch and close the second switch; otherwise, determine that the operating mode for the next moment is inductor mode, close the first switch and open the second switch.

[0013] If the current operating mode is transformer mode, determine whether the current operating frequency is less than (y1) Hz. If so, determine that the operating mode for the next moment is inductor mode, close the first switch and open the second switch; otherwise, determine that the operating mode for the next moment is transformer mode, open the first switch and close the second switch.

[0014] By applying the technical solution of this invention, a power supply device with a multi-converter cascaded topology including inductor mode and transformer mode is designed. This overcomes the problem of large inductor heating during high-frequency operation in simple inductor mode, and improves the load-side voltage and output capacity in transformer mode, which helps to give full play to the advantages of large-capacity power supply of multiple cascaded current transformers. In order to avoid magnetic saturation of the output transformer, a converter output mode safety switching control method based on frequency range hysteresis is adopted during the switching process between inductor mode and transformer mode, which also avoids back-and-forth switching between the two output modes at a specific frequency point. Attached Figure Description

[0015] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0016] Figure 1 A topology diagram of a dual converter power supply device based on frequency range hysteresis control according to an embodiment of the present invention is shown.

[0017] Figure 2A topology diagram of a multi-converter power supply device based on frequency range hysteresis control according to an embodiment of the present invention is shown.

[0018] Figure 3 A schematic diagram of the operating frequency ranges in inductor mode and transformer mode according to an embodiment of the present invention is shown;

[0019] Figure 4 A flowchart of a converter power supply method based on frequency range hysteresis control according to an embodiment of the present invention is shown. Detailed Implementation

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. 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 a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0021] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0022] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0023] like Figure 1 and Figure 2 As shown, the present invention provides a converter power supply device based on frequency range hysteresis control. The device includes at least two converters, at least two transformers, a first switch and a second switch. The number of converters is the same as the number of transformers, and each converter includes two inverters.

[0024] The secondary sides of all transformers are connected in series and then connected in series with the load to form a circuit. The first end of the load is connected to the first end of the secondary side of the first transformer, and the second end of the load is connected to the second end of the secondary side of the last transformer. The primary sides of all transformers are connected to a converter. The first end of the primary side of each transformer is connected to one inverter in the corresponding transformer, and the second end is connected to another inverter in the corresponding transformer.

[0025] The first end of the first switch is connected to the middle of the primary side of the first transformer, and the second end is connected to the second end of the second switch;

[0026] The second switch is connected in series between the secondary side of the first transformer and the secondary side of the second transformer. The first end of the second switch is connected to the second end of the first transformer, and the second end is connected to the first end of the second transformer.

[0027] In inductor mode, the first switch is closed and the second switch is open; in transformer mode with cascaded secondary transformers, the first switch is open and the second switch is closed.

[0028] This invention designs a power supply device with a multi-converter cascaded topology that includes inductor mode and transformer mode. It overcomes the problem of large inductor heat generation during high-frequency operation in pure inductor mode, and improves the load-side voltage and output capacity in transformer mode, which helps to give full play to the advantages of high-capacity power supply of multiple cascaded current transformers. In order to avoid magnetic saturation of the output transformer, a converter output mode safety switching control method based on frequency range hysteresis is adopted during the switching process between inductor mode and transformer mode, which also avoids back-and-forth switching between the two output modes at a specific frequency point.

[0029] In this invention, such as Figure 1The diagram shows a power supply device with two converters. In inductor mode, i.e., at a low operating frequency, switch SW1 is closed and switch SW2 is open. At this time, the output voltage of the first converter is also the load-side voltage, which is determined solely by the first converter, and the output voltage of the second converter is 0. In transformer mode, i.e., after the operating frequency increases to a certain value, the output voltage of the first converter alone cannot meet the load voltage requirements, and the inductor of the first converter generates significant heat. Therefore, a switch needs to be switched. In this case, switch SW1 is open and switch SW2 is closed, and both the first and second converters are put into use. The two converters operate in transformer mode with cascaded secondary transformers. At this time, the load-side voltage is jointly determined by the output voltages of both converters.

[0030] The advantage of this topology is that it overcomes the problem of large inductor heat generation during high-frequency operation in the pure inductor mode, and increases the voltage and output capacity on the load side in the transformer mode, which helps to give full play to the advantages of large-capacity power supply of multiple cascaded current transformers.

[0031] For higher voltage output applications, multiple transformers can be cascaded after the two converters, such as... Figure 2 As shown.

[0032] exist Figure 2 In the transformer mode (with switch SW2 closed and switch SW1 open), the working principle of the transformer can be derived from the following formula, which serves as the basis for designing this type of multi-converter.

[0033] Uout=a*(Uin_1+Uin_2+…+Uin_n)

[0034] In the formula, Uout is the load-side voltage, a is the reciprocal of the transformer turns ratio, and Uin_1, Uin_2, ..., Uin_n are the output voltages of the first, second, ..., nth transformers, respectively.

[0035] According to one embodiment of the present invention, the operating frequency range of the inductor mode is (0~y2)Hz, and the operating frequency range of the transformer mode is greater than (y1)Hz, and y1≤y2.

[0036] Furthermore, to avoid switching between the two output modes at a specific frequency point, y1 < y2 is set, even though the maximum operating frequency of the inductor mode is greater than the minimum operating frequency of the transformer mode. The schematic diagram of its operating frequency range is shown below. Figure 3 As shown.

[0037] Because prolonged or high-frequency operation in inductor mode leads to increased equivalent inductive reactance and significant system heat generation, it is detrimental to the safe operation of the inductor. Simultaneously, transformer operation at low frequencies can cause saturation within a short period. Therefore, this invention employs inductor mode at low frequencies and transformer mode at high frequencies to achieve high-capacity, high-voltage output. The invention addresses the issue of reliable frequency switching between the two operating modes. Specifically, the main control system controls the output mode switching switch based on the load's operating frequency, switching from inductor mode to transformer mode. Switches SW1 and SW2 enable two operating states for the output transformer: when switch SW1 is closed and switch SW2 is open, the output is in inductor mode; when switch SW2 is closed and switch SW1 is open, the output is in transformer mode.

[0038] To avoid magnetic saturation of the output transformer, a converter output mode safety switching control method based on frequency range hysteresis is adopted during the switching process between inductor mode and transformer mode. This also avoids back-and-forth switching between the two output modes at a specific frequency point.

[0039] like Figure 4 As shown, the present invention also provides a power supply method for a converter power supply device based on frequency range hysteresis control, wherein the method uses any of the above-described devices for power supply, and the method includes:

[0040] Determine the current operating mode;

[0041] If the current operating mode is inductor mode, determine whether the current operating frequency is greater than (y2) Hz. If so, determine that the operating mode for the next moment is transformer mode, open the first switch and close the second switch; otherwise, determine that the operating mode for the next moment is inductor mode, close the first switch and open the second switch.

[0042] If the current operating mode is transformer mode, determine whether the current operating frequency is less than (y1) Hz. If so, determine that the operating mode for the next moment is inductor mode, close the first switch and open the second switch; otherwise, determine that the operating mode for the next moment is transformer mode, open the first switch and close the second switch.

[0043] Because inductor mode and transformer mode operate within a frequency hysteresis range, such as Figure 3 The shaded area shown effectively prevents the switching frequency between the two working modes, ensuring the safe and effective execution of the output mode switching switch.

[0044] In summary, this invention provides a converter power supply device and method based on frequency range hysteresis control. It designs a power supply device with a multi-converter cascaded topology including inductor mode and transformer mode, overcoming the problem of high inductor heating during high-frequency operation in pure inductor mode, and improving the load-side voltage and output capacity in transformer mode, thus maximizing the advantages of high-capacity power supply from multiple cascaded current transformers. To avoid magnetic saturation of the output transformer, a safe switching control method based on frequency range hysteresis is adopted during the switching between inductor mode and transformer mode, also avoiding back-and-forth switching between the two output modes at a specific frequency point.

[0045] The parts of this invention not described in detail are techniques known to those skilled in the art.

[0046] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0047] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0048] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A converter power supply device based on frequency range hysteresis control, characterized in that, The device includes at least two converters, at least two transformers, a first switch and a second switch, wherein the number of converters is the same as the number of transformers, and each converter includes two inverters. The secondary sides of all transformers are connected in series and then connected in series with the load to form a circuit. The first end of the load is connected to the first end of the secondary side of the first transformer, and the second end of the load is connected to the second end of the secondary side of the last transformer. The primary sides of all transformers are connected to a converter. The first end of the primary side of each transformer is connected to one inverter in the corresponding transformer, and the second end is connected to another inverter in the corresponding transformer. The first end of the first switch is connected to the middle of the primary side of the first transformer, and the second end is connected to the second end of the second switch; The second switch is connected in series between the secondary side of the first transformer and the secondary side of the second transformer. The first end of the second switch is connected to the second end of the first transformer, and the second end is connected to the first end of the second transformer. In inductor mode, the first switch is closed and the second switch is open; in transformer mode with cascaded secondary transformers, the first switch is open and the second switch is closed.

2. The apparatus according to claim 1, characterized in that, The operating frequency range of the inductor mode is (0~y2)Hz, and the operating frequency range of the transformer mode is greater than (y1)Hz, and y1≤y2.

3. A power supply method for a converter power supply device based on frequency range hysteresis control, characterized in that, The method is powered by the device described in claim 1 or 2, and the method includes: Determine the current operating mode; If the current operating mode is inductor mode, determine whether the current operating frequency is greater than (y2) Hz. If so, determine that the operating mode for the next moment is transformer mode, open the first switch and close the second switch; otherwise, determine that the operating mode for the next moment is inductor mode, close the first switch and open the second switch. If the current operating mode is transformer mode, determine whether the current operating frequency is less than (y1) Hz. If so, determine that the operating mode for the next moment is inductor mode, close the first switch and open the second switch; otherwise, determine that the operating mode for the next moment is transformer mode, open the first switch and close the second switch.

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