DC / dc power converter, method for controlling switching of a dc / dc power converter, dc / dc power converter arrangement, and system

Abstract

A DC / DC power converter (4) for converting a voltage (Vin) at an input (IN1, IN2) to a voltage (Vout) at an output of the DC / DC power converter (4), wherein the output voltage (Vout) is a multiple of the input voltage (Vin). The DC / DC power converter (4) comprises two switching circuits (1, 2) electrically connected in series, two capacitor units (C1, C2) electrically connected in series, and a resonance circuit (3) comprising a resonance capacitor (Cr) and a resonance inductor (Lr). A first switching circuit (1) of the two switching circuits (1, 2) is electrically connected to one side of a first capacitor unit (C1), which side of the first capacitor unit (C1) is opposite to another side of the first capacitor unit (C1), which other side of the first capacitor unit (C1) is connected to a second capacitor unit (C2) of the two capacitor units (C1, C2). Switches (11, 12) of the first switching circuit (1) are controllable semiconductor switches. The first switching circuit (1) comprises one or more diode units (D11) electrically connecting the first capacitor unit (C1) to the two switching units (11, 12) of the first switching circuit (1).

Description

Technical Field

[0001] This disclosure relates to a DC / DC power converter, a method for controlling the switching of such a DC / DC power converter, a cascaded DC / DC power converter arrangement comprising multiple DC / DC power converters, and a system including such a DC / DC power converter or such DC / DC power converter arrangement. In particular, this disclosure relates to a DC / DC power converter including a resonant circuit. Background Technology

[0002] DC / DC power converters are used to convert one DC voltage level to another. Therefore, these DC / DC power converters are used to connect one DC voltage level to another. DC / DC power converters are used in various technical fields. For example, DC / DC power converters can be used in renewable energy devices, such as photovoltaic or wind power devices, to convert one DC voltage level to another. DC / DC power converters can also be used in fixed voltage transmission applications, such as DC / DC conversion in power supplies used in server power supplies or telecommunications equipment. Summary of the Invention

[0003] The embodiments disclosed herein are also based on the following considerations of the inventors:

[0004] Figure 1 A DC / DC power converter based on the resonant balancer concept is illustrated. This DC / DC power converter includes a resonant circuit with a resonant capacitor Cr and a resonant inductor Lr, used to convert a first DC voltage Vin (input voltage) at input terminals IN1 and IN2 into a second DC voltage Vout (output voltage) at output terminals OUT1 and OUT2, where the second DC voltage Vout is a multiple of the first DC voltage Vin. That is, the second DC voltage Vout is greater than the first DC voltage Vin. For example, the DC / DC power converter can be used to convert a first DC voltage Vin (e.g., Vin = 1V) into a second DC voltage Vout such that the second DC voltage Vout is twice the first DC voltage Vin (e.g., Vout = 2.1V = 2V). The resonant balancer concept is used to generate a mirror effect from one voltage level to another. Because the DC / DC power converter based on the resonant balancer concept operates with almost no switching losses, the main advantage of the resonant balancer concept is high efficiency. That is, due to the use of the resonant balancer concept, Figure 1 The switching of switches S01, S02, S03, and S04 in the DC / DC power converter causes almost no switching losses during the operation of the DC / DC power converter.

[0005] like Figure 1 As shown, four controllable semiconductor switches S01, S02, S03, and S04, in the form of insulated-gate bipolar transistors (IGBTs), are electrically connected in series. The term "connection" is used herein as a synonym for "electrical connection." The resonant circuit (also referred to as a resonant loop) comprises a resonant capacitor Cr and a resonant inductor Lr connected in series. One side of the series connection of the resonant capacitor Cr and the resonant inductor Lr is connected to the node between the top two switches S01 and S02 in the series connection of the four switches S01, S02, S03, and S04, and the other side is connected to the node between the bottom two switches S03 and S04 in the series connection of the four switches S01, S02, S03, and S04.

[0006] The terms "top" and "highest" can be used synonyms for the term "topmost." That is, the topmost element in a series connection of multiple elements can be referred to as the top element or the highest element in the series connection. The highest / topmost element in a series connection of multiple elements is located at the highest / topmost position in the series connection of multiple elements. The topmost element is the element preceding the second topmost element in a series connection of multiple elements. The second topmost element in a series connection of multiple elements is the element following the topmost element and preceding the third topmost element. The third topmost element in a series connection of multiple elements is the element following the second topmost element and preceding the fourth topmost element, and so on.

[0007] The terms "bottom" and "lowest" can be used synonyms for the term "bottommost." That is, the bottommost element in a series connection of multiple elements can be referred to as the bottom element or the lowest element in that series connection. The lowest / bottommost element in a series connection of multiple elements is located at the lowest / bottommost position in the series connection of multiple elements. The bottommost element is the element following the second bottommost element in a series connection of multiple elements. The second bottommost element in a series connection of multiple elements is the element preceding the bottommost element and the element following the third bottommost element. The third bottommost element in a series connection of multiple elements is the element preceding the second bottommost element and the element following the fourth bottommost element, and so on.

[0008] The term "prior" can be used as a synonym for the term "preceding". The term "subsequent" can be used as a synonym for the term "following".

[0009] like Figure 1As shown, the series connection of two capacitors C1 and C2 is connected in parallel to the series connection of four switches S01, S02, S03, and S04. The midpoint of the series connection of the two capacitors C1 and C2 is interconnected with the midpoint of the series connection of the four switches S01, S02, S03, and S04.

[0010] like Figure 1 As shown, the input of the DC / DC power converter is connected in parallel to the topmost capacitor C1 (the first capacitor) of the series connection of two capacitors C1 and C2, and in parallel to the two topmost switches S01 and S02. Specifically, the second input terminal IN2 of this input is connected to one side of the topmost capacitor C1, which forms a midpoint with the bottommost capacitor C2 (the second capacitor), and the first input terminal IN1 of this input is connected to the other side of the topmost capacitor C1. The output of the DC / DC power converter is connected in parallel to the series connection of two capacitors C1 and C2 and the series connection of four switches S01, S02, S03, and S04. Specifically, as... Figure 1 As shown, the first output terminal OUT1 is connected to one side of the series connection of the two capacitors C1 and C2, which are connected to the first input terminal IN1, and to one side of the series connection of the four switches S01, S02, S03, and S04. The second output terminal OUT2 is connected to the other side of the series connection of the two capacitors C1 and C2 and the other side of the series connection of the four switches S01, S02, S03, and S04. An optional third output terminal OUT3 is electrically connected to the midpoint of the series connection of the two capacitors C1 and C2 and the midpoint of the series connection of the four switches S01, S02, S03, and S04.

[0011] The input (formed by two input terminals IN1 and IN2) and output (formed by two output terminals OUT1 and OUT2, and an optional third output terminal OUT3) of the DC / DC power converter can be referred to as the energy ports of the DC / DC power converter. Four switches S01, S02, S03, and S04 are switchable, energizing a resonant circuit with a constant duty cycle between the input (i.e., the energy port between IN1 and IN2) and the output (the energy port between OUT1 and OUT2) of the DC / DC power converter to match these two energy ports (i.e., the energy port between IN1 and IN2 = the energy port between OUT1 and OUT3 = the energy port between OUT2 and OUT3). For operation of the DC / DC power converter, the first switch S01 (the topmost switch) and the third switch S03 (the second bottommost switch) are complementary to the second switch S02 (the second topmost switch) and the fourth switch S04 (the bottommost switch), which are both connected and disconnected. That is, when the first switch S01 and the third switch S03 switch from the non-conducting state to the conducting state, the second switch S02 and the fourth switch S04 switch from the conducting state to the non-conducting state, and vice versa.

[0012] With the first and third switches S01 and S03 in the ON state (and the second and fourth switches S02 and S04 in the OFF state), the resonant circuit begins to resonate using the first capacitor C1 as the voltage source. With the second and fourth switches S02 and S04 in the ON state (and the first and third switches S01 and S03 in the OFF state), the resonant circuit begins to resonate using the second capacitor C2 as the voltage source. Therefore, during this operation of the DC / DC power converter, energy exchange occurs between the two voltage sources C1 and C2, which internally balances the voltage levels of these two sources after several resonant cycles. Because... Figure 1 The DC / DC power converter converts the first voltage Vin at the input to the second voltage Vout at the output without current isolation, so the DC / DC power converter is a non-isolated DC / DC power converter.

[0013] Each switch S01, S02, S03, and S04 of the DC / DC power converter needs to have a minimum blocking voltage greater than the highest voltage Vin at the input (i.e., between the first input IN1 and the second input IN2). Therefore, in practical implementations, these switches are implemented as high-voltage devices to match high DC link requirements (i.e., to match a high value of the first voltage Vin that can be received at the input of the DC / DC power converter). The use of high-voltage devices increases cost and reduces efficiency. For example, in solar photovoltaic (PV) systems, DC / DC power converters (e.g.,...) Figure 1 The input of the DC / DC power converter shown may accept a first voltage up to 1500V. Typically, for a failure-in-time (FIT) rate of 100%, the device operating voltage is 65% of the blocking voltage. That is, if the first voltage received at the input of the DC / DC power converter reaches 1500V, the rated blocking voltage of switches S01, S02, S03, and S04 needs to be at least 2308V (1500V = 0.65·2308V).

[0014] In view of the above-mentioned problems and disadvantages, embodiments of the present invention aim to improve the cost and efficiency of DC / DC power converters including resonant converters. The objective is to provide a DC / DC power converter with improved efficiency and cost.

[0015] This disclosure provides a first aspect of a DC / DC power converter for converting a voltage at its input to a voltage at its output, wherein the output voltage is a multiple of the input voltage. The DC / DC power converter includes two switching circuits connected in series, two capacitor units connected in series, and a resonant circuit including a resonant capacitor and a resonant inductor. Each capacitor unit includes one or more capacitors, and the series connection of two capacitor units is connected in parallel to the series connection of the two switching circuits. The resonant circuit is electrically connected to the two switching circuits. A first capacitor unit of the two capacitor units is connected in parallel to the input. The series connection of the two switching circuits is connected in parallel to the output. Each switching circuit includes two switching units connected in series, wherein each switching unit includes two or more switches connected in series. The first switching circuit of the two switching circuits is electrically connected to one side of the first capacitor unit, which is opposite to the other side of the first capacitor unit, which is connected to a second capacitor unit of the two capacitor units. The switches of the first switching circuit are controllable semiconductor switches. The first capacitor unit includes two or more capacitors connected in series. The first switching circuit includes one or more diode units, which electrically connect the first capacitor unit to two switching units of the first switching circuit.

[0016] The DC / DC power converter according to the first aspect reduces losses and thus improves efficiency. Furthermore, it also reduces costs. That is, since each switching unit in the two switching circuits includes two or more switches, each switch can be implemented with a lower voltage semiconductor switch (such as...) compared to the case where each switching unit is replaced by a single semiconductor switch. Figure 1(The case in a DC / DC power converter). Therefore, the DC / DC power converter topology according to the first aspect is advantageous for realizing a highly integrated, low-component, and high-efficiency DC / DC power converter.

[0017] Furthermore, the presence of two or more capacitors in the first capacitor unit and one or more diode units in the first switching circuit allows for a DC / DC power converter with improved cost and component count. Specifically, due to the presence of two or more capacitors in the first capacitor unit and one or more diode units in the first switching circuit, the controllable semiconductor switch of each switching unit in the first switching circuit can be switched individually to switch the corresponding switching unit from an on state to an off state, and vice versa. Therefore, there is no need for pre-matching of the controllable semiconductor switches of the first switching circuit for similar switching times, nor is there a need for complex drive circuitry to provide drive and control signals to jointly switch the controllable semiconductor switches of each switching unit in the first switching circuit. This reduces the complexity, cost, and component count of implementing the DC / DC power converter according to the first aspect (especially implementing its first switching circuit).

[0018] A DC / DC power converter can be a DC / DC power converter without current isolation between its input and output. That is, a DC / DC power converter can be a non-isolated DC / DC power converter. A DC / DC power converter can also be called a resonant DC / DC power converter, a DC / DC power converter based on the concept of a resonant balancer, a resonant balancer DC / DC power converter, or a resonant switched capacitor converter.

[0019] The voltage level at the output (also called the output voltage) is greater than the voltage level at the input (also called the input voltage), wherein the voltage level at the output is a multiple of the voltage level at the input. Specifically, the voltage level at the output can be an integer multiple of the voltage level at the input. That is, the output voltage can be an integer multiple of the input voltage.

[0020] Specifically, the absolute value of the output voltage is greater than the absolute value of the input voltage, where the absolute value of the output voltage is a multiple of the absolute value of the input voltage. The absolute value of the output voltage can be an integer multiple of the absolute value of the input voltage.

[0021] The term “connection” is used as a synonym for the term “electrical connection”.

[0022] The first capacitor cell is connected to one side of the first switching cell but not to the second capacitor cell of the two capacitor cells. The other side of the first capacitor cell and one side of the second capacitor cell form the midpoint of the series connection of the two capacitor cells. The midpoint of the series connection of the two elements corresponds to the node between the two elements. For example, the midpoint of the series connection of the two switching cells in a switching circuit corresponds to the node between the two switching cells in that switching circuit.

[0023] A capacitor unit has two sides. When a capacitor unit includes or corresponds to a single capacitor, the two sides of the capacitor unit correspond to the two sides of that capacitor. When a capacitor unit includes two or more capacitors, these two or more capacitor units are connected in series. In this case, the two sides of the capacitor unit correspond to the two ends of the series connection of the two or more capacitors. One side of a capacitor unit can be referred to as a terminal of the capacitor unit. Correspondingly, one side of a capacitor can be referred to as a terminal of the capacitor. Thus, the first switching circuit in the two switching circuits is electrically connected to the first terminal of the first capacitor unit, the first terminal of the first capacitor unit is opposite to the second terminal of the first capacitor unit, and the second terminal of the first capacitor unit is connected to the second capacitor unit among the two capacitor units. The first terminal of the first capacitor unit is not connected to the second capacitor unit among the two capacitor units.

[0024] The first capacitor unit includes or corresponds to two or more capacitors connected in series. The second capacitor unit includes or corresponds to one or more capacitors. When the second capacitor unit includes or corresponds to two or more capacitors, the two or more capacitors are connected in series. That is, the two or more capacitors of the first capacitor unit are connected in series with one or more capacitors of the second capacitor unit.

[0025] These two capacitor units can be referred to as input capacitor units, DC bus capacitor units, or high-capacity storage capacitor units.

[0026] A resonant circuit can be electrically connected between the midpoint of the two switching units of the first switching circuit and the midpoint of the two switching units of the second switching circuit. A resonant circuit can also be called a resonant loop. A resonant capacitor can include or correspond to one or more capacitors connected in series and / or in parallel. A resonant inductor can include or correspond to one or more inductors connected in series and / or in parallel. The capacitance of each capacitor in the two or more capacitors of the first capacitor unit and one or more capacitors of the second capacitor unit is greater than the capacitance of the resonant capacitor, such that these capacitors do not affect the resonance of the resonant circuit.

[0027] Each switching circuit includes or corresponds to two switching units connected in series. Each switching unit includes or corresponds to two or more switches connected in series. That is, the switching units of two switching circuits are connected in series. The switches of two switching circuits are connected in series.

[0028] Examples of controllable semiconductor switches are bipolar junction transistors (BJTs), field-effect transistors (FETs) (e.g., metal-oxide-semiconductor field-effect transistors (MOSFETs)), and insulated-gate bipolar transistors (IGBTs). Therefore, the switch in the first switching circuit can be one or more BJTs, one or more FETs (e.g., one or more MOSFETs), and / or one or more IGBTs. That is, the controllable semiconductor switch can be a transistor. According to embodiments, the switches in the first switching circuit have the same switch type, specifically the same transistor type.

[0029] When the switch is a controllable semiconductor switch (especially a transistor), the diode can be connected in anti-parallel to the controllable semiconductor switch. When the switch is an IGBT, the diode can be connected in anti-parallel to the IGBT. Specifically, the diode is connected in parallel to the IGBT such that the anode of the diode is connected to the emitter terminal of the IGBT, and the cathode of the diode is connected to the collector terminal of the IGBT.

[0030] The number of switches in each switching unit of the first switching circuit in both switching circuits can be the same. Optionally or additionally, the number of switches in each switching unit of the second switching circuit in both switching circuits can be the same. The number of switches in each switching unit of the DC / DC power converter can be the same.

[0031] In an embodiment of the first aspect, the switch of the second switching circuit in the two switching circuits is an uncontrollable semiconductor switch. Optionally, in an embodiment of the first aspect, the switch of the second switching circuit in the two switching circuits is a controllable semiconductor switch, the second capacitor unit includes two or more capacitors connected in series, and the second switching circuit includes one or more diode units that electrically connect the second capacitor unit to the two switching units of the second switching circuit.

[0032] When the switch in the second switching circuit is an uncontrollable semiconductor switch, the voltage across the uncontrollable semiconductor switch caused by the switching of the controllable semiconductor switch in the first switching circuit switches the switch in the second switching circuit. The control unit can control this switching. Therefore, since only the switching of the first switching circuit is controlled, the control workload is reduced, thereby lowering the cost of controlling the DC / DC power converter.

[0033] When both the switches in the first and second switching circuits are controllable semiconductor switches, the power direction between the input and output of the DC / DC power converter can be bidirectional. This is advantageous because power can be transferred from the input to the output and from the output to the input of the DC / DC power converter. Furthermore, the two or more capacitors in the second capacitor unit and one or more diode units in the second switching circuit allow for a DC / DC power converter with improved cost and component count. That is, due to the presence of the two or more capacitors in the second capacitor unit and one or more diode units in the second switching circuit, the controllable semiconductor switch of each switching unit of the second switching circuit can be switched individually to switch the corresponding switching unit from an on state to an off state, and vice versa. Therefore, there is no need to pre-match the controllable semiconductor switches of the second switching circuit for similar switching times, nor is there a need for complex drive circuitry to provide drive and control signals to jointly switch the controllable semiconductor switches of each switching unit of the second switching circuit. This reduces the complexity, cost, and component count of implementing the DC / DC power converter according to the first aspect embodiment (especially its second switching circuit).

[0034] Therefore, in the case where the switching of each switching unit in two switching circuits (e.g., a first switching circuit and optionally a second switching circuit) is a controllable semiconductor switch, the corresponding capacitor unit comprises two or more capacitors connected in series, and the switching circuit comprises one or more diode units that electrically connect the corresponding capacitor unit to the two switching units of the switching circuit. The corresponding capacitor unit corresponds to the capacitor unit whose position in the series connection of the two capacitor units is the same as the position of the switching circuit in the series connection of the two switching circuits.

[0035] The switch in the second switching circuit of two switching circuits can be one or more uncontrolled semiconductor switches (e.g., diodes) and / or one or more controlled semiconductor switches (e.g., transistors). Uncontrolled semiconductor switches can also be called uncontrolled unidirectional semiconductor switches. An example of an uncontrolled semiconductor switch is a diode.

[0036] The switches in the second switching circuit can be one or more BJTs, one or more FETs (e.g., one or more MOSFETs), one or more IGBTs, and / or one or more diodes. According to an embodiment, the switches in the second switching circuit have the same switch type.

[0037] When the switch is a controllable semiconductor switch (especially a transistor), the diode can be connected in anti-parallel to the controllable semiconductor switch. When the switch is an IGBT, the diode can be connected in anti-parallel to the IGBT. Specifically, the diode is connected in parallel to the IGBT such that the anode of the diode is connected to the emitter terminal of the IGBT, and the cathode of the diode is connected to the collector terminal of the IGBT.

[0038] When the switches in the first and second switching circuits are controllable semiconductor switches, the power flow between the input and output of the DC / DC power converter can be bidirectional. Therefore, in this case, the DC / DC power converter can be used to convert a first voltage at its output to a smaller second voltage at its input, where the second voltage is a fraction of the first voltage. Specifically, the second voltage can be an integer fraction of the first voltage. That is, in the above case, power can be transferred from the input to the output of the DC / DC power converter and from its output to the input.

[0039] In an embodiment of the first aspect, where the two or more switches of each switching unit in the two switching circuits are two or more controllable semiconductor switches: the number of the two or more capacitors of the corresponding capacitor unit corresponds to the number of the two or more switches of each switching unit in the switching circuit, and the number of one or more diode units in the switching circuit is one less than the number of the two or more switches of each switching unit in the switching circuit.

[0040] In this case, the switching unit of the switching circuit includes the same number of switches.

[0041] The presence of two or more capacitors in the corresponding capacitor unit and one or more diode units in the switching circuit allows for a DC / DC power converter with improved cost and component count. Specifically, due to the presence of the aforementioned two or more capacitors and one or more diode units, the controllable semiconductor switch of each switching unit in the switching circuit can be switched individually to switch the corresponding switching unit from an on state to an off state, and vice versa. Therefore, there is no need for pre-matching of the controllable semiconductor switches in the switching circuit for similar switching times, nor is there a need for complex drive circuitry to provide drive and control signals to jointly switch the controllable semiconductor switches of each switching unit in the switching circuit. This reduces the complexity, cost, and component count of implementing the DC / DC power converter according to the first aspect embodiment.

[0042] The switching circuit corresponds to the first switching circuit. Optionally, if the switch in the second switching circuit is a controllable semiconductor switch, the switching circuit also corresponds to the second switching circuit.

[0043] In other words, the number of two or more capacitors in the first capacitor unit can be equal to the number of two or more switches in each switching unit of the first switching circuit, and the number of one or more diode units in the first switching circuit can be one less than the number of two or more switches in each switching unit of the first switching circuit, wherein the two switching units of the first switching circuit include the same number of switches. When the switches in each switching unit of the second switching circuit are controllable semiconductor switches, the number of two or more capacitors in the second capacitor unit can be equal to the number of two or more switches (controllable semiconductor switches) in each switching unit of the second switching circuit, and the number of one or more diode units in the second switching circuit can be one less than the number of two or more switches in each switching unit of the second switching circuit. The two switching units of the second switching circuit include the same number of switches.

[0044] Therefore, in the case where each switching unit of the switching circuit (e.g., a first switching circuit and optionally a second switching circuit) includes two controllable semiconductor switches as switches, the corresponding capacitor unit includes two capacitors and the switching circuit includes a diode unit. In the case where each switching unit of the switching circuit includes three controllable semiconductor switches as switches, the corresponding capacitor unit includes three capacitors and the switching circuit includes two diode units, and so on.

[0045] In an embodiment of the first aspect, in the case where each switching unit of the corresponding switching circuit includes two controllable semiconductor switches connected in series, the corresponding switching circuit includes a diode unit, and the corresponding capacitor unit includes two capacitors, the midpoint of the series connection of the two capacitors of the corresponding capacitor unit is connected to the midpoint of the series connection of the two switches of the first switching unit of the corresponding switching circuit via the first diode of the diode unit, and is connected to the midpoint of the series connection of the two switches of the second switching unit of the corresponding switching circuit via the second diode of the diode unit.

[0046] For the reasons mentioned above, the two or more capacitors of the corresponding capacitor unit and one or more diode units of the corresponding switching circuit allow for a DC / DC power converter with improved cost and component count.

[0047] The diode unit may include two diodes. The corresponding switching circuit corresponds to the first switching circuit and optionally to the second switching circuit.

[0048] In an embodiment of the first aspect, when the corresponding switching circuit is a first switching circuit: the corresponding capacitor unit is a first capacitor unit, and the second switching unit of the first switching circuit is connected to the midpoint of the series connection of the two switching circuits. The midpoint of the series connection of the two capacitors of the first capacitor unit is connected to the anode of the first diode, wherein the cathode of the first diode is connected to the midpoint of the series connection of the two switches of the first switching unit. The midpoint of the series connection of the two capacitors of the first capacitor unit is connected to the cathode of the second diode, wherein the anode of the second diode is connected to the midpoint of the series connection of the two switches of the second switching unit.

[0049] For the reasons mentioned above, the two or more capacitors of the first capacitor unit and one or more diode units of the first switching circuit allow for a DC / DC power converter with improved cost and component count.

[0050] Optionally or additionally, when the corresponding switching circuit is a second switching circuit: the corresponding capacitor unit is a second capacitor unit, and the first switching unit of the second switching circuit is connected to the midpoint of the series connection of the two switching circuits. The midpoint of the series connection of the two capacitors of the second capacitor unit is connected to the anode of the first diode, wherein the cathode of the first diode is connected to the midpoint of the series connection of the two switches of the first switching unit. The midpoint of the series connection of the two capacitors of the second capacitor unit is connected to the cathode of the second diode, wherein the anode of the second diode is connected to the midpoint of the series connection of the two switches of the second switching unit.

[0051] For the reasons mentioned above, the two or more capacitors of the second capacitor unit and one or more diode units of the second switching circuit allow for a DC / DC power converter with improved cost and component count.

[0052] In an embodiment of the first aspect, where each switching unit of the corresponding switching circuit includes three or more controllable semiconductor switches connected in series, the corresponding switching circuit includes two or more diode units, and the corresponding capacitor unit includes three or more capacitors: each node between two capacitors of the corresponding capacitor unit is connected via a first diode of the corresponding diode unit in the two or more diode units to a first node between two switches of the first switching unit in the two switching units of the corresponding switching circuit, and is connected via a second diode of the corresponding diode unit to a second node between two switches of the second switching unit in the two switching units of the corresponding switching circuit. The position of the first node in the series connection of the three or more switches in the first switching unit corresponds to the position of the second node in the series connection of the three or more switches in the second switching unit. The nodes of the series connection (between two capacitors) of the three or more capacitors of the corresponding capacitor unit are connected to different nodes of the two switching units of the corresponding switching circuit.

[0053] For the reasons mentioned above, the three or more capacitors in the corresponding capacitor unit and the two or more diode units in the corresponding switching circuit allow for a DC / DC power converter with improved cost and component count.

[0054] The positions of each node between two capacitors in the series connection of three or more capacitors in the corresponding capacitor unit, the positions of the corresponding first node between two switches in the series connection of three or more switches in the first switch unit, and the positions of the corresponding second node between two switches in the series connection of three or more switches in the second switch unit correspond to each other.

[0055] In other words, the node between the two capacitors of the capacitor unit can be connected via a diode unit of the corresponding switching circuit to the first node between the two switches of the first switching unit of the corresponding switching circuit. The position of the first node in the series connection of three or more switches of the first switching unit is the same as the position of the node between the two capacitors in the series connection of three or more capacitors of the capacitor unit. Furthermore, the node between the two capacitors of the capacitor unit can be connected via a diode unit to the second node between the two switches of the second switching unit of the corresponding switching circuit. The position of the second node in the series connection of three or more switches of the second switching unit is the same as the position of the node between the two capacitors in the series connection of three or more capacitors of the capacitor unit.

[0056] The corresponding switching circuit corresponds to the first switching circuit and optionally to the second switching circuit.

[0057] In an embodiment of the first aspect, when the corresponding switching circuit is a first switching circuit: the corresponding capacitor unit is a first capacitor unit, and the second switching unit of the first switching circuit is connected to the midpoint of the series connection of the two switching circuits. Each node between the two capacitors of the first capacitor unit is connected to the anode of the first diode of the corresponding diode unit in two or more diode units, wherein the cathode of the first diode is connected to the corresponding first node between the two switches of the first switching unit in the two switching units of the first switching circuit. Furthermore, each node between the two capacitors of the first capacitor unit is connected to the cathode of the second diode of the corresponding diode unit, wherein the anode of the second diode is connected to the corresponding second node between the two switches of the second switching unit in the two switching units of the first switching circuit.

[0058] For the reasons mentioned above, the three or more capacitors in the first capacitor unit and the two or more diode units in the first switching circuit allow for a DC / DC power converter with improved cost and component count.

[0059] Optionally or additionally, when the corresponding switching circuit is a second switching circuit: the corresponding capacitor unit is a second capacitor unit, and the first switching unit of the second switching circuit is connected to the midpoint of the series connection of the two switching circuits. Each node between the two capacitors of the second capacitor unit is connected to the anode of the first diode of the corresponding diode unit in two or more diode units, wherein the cathode of the first diode is connected to the corresponding first node between the two switches of the first switching unit in the two switching units of the second switching circuit. Furthermore, each node between the two capacitors of the second capacitor unit is connected to the cathode of the second diode of the corresponding diode unit, wherein the anode of the second diode is connected to the corresponding second node between the two switches of the second switching unit in the two switching units of the second switching circuit.

[0060] For the reasons mentioned above, the three or more capacitors in the second capacitor unit and the two or more diode units in the second switching circuit allow for a DC / DC power converter with improved cost and component count.

[0061] In an embodiment of the first aspect, the dimensions of the two or more capacitors of the first capacitor unit are such that the voltage at each capacitor of the first capacitor unit corresponds to the voltage at the first capacitor unit divided by the number of capacitors in the first capacitor unit.

[0062] This is advantageous because one or more capacitors in the first capacitor unit provide voltage balance across the switches of the first switching circuit, ensuring that the same voltage is applied to the switches of the first switching circuit. Specifically, a voltage corresponding to the voltage at the first capacitor unit divided by the number of switches in the first switching circuit can be applied to the switches of the first switching circuit. Therefore, the rated voltage of the switches in the first switching circuit can correspond to the voltage at the first capacitor unit divided by the number of switches in the first switching circuit.

[0063] This also applies to the second switching circuit in both switching circuits when each switching unit of the second switching circuit is a controllable semiconductor switch and the second capacitor unit includes two or more capacitors. That is, the size of the two or more capacitors in the second capacitor unit is such that the voltage at each capacitor of the second capacitor unit corresponds to the voltage at the second capacitor unit divided by the number of capacitors in the second capacitor unit.

[0064] This is advantageous because one or more capacitors in the second capacitor unit provide voltage balance across the switches of the second switching circuit, ensuring that the same voltage is applied to the switches of the second switching circuit when the input voltage of the DC / DC power converter is received. Specifically, a voltage corresponding to the voltage at the second capacitor unit divided by the number of switches in the second switching circuit can be applied to the switches of the second switching circuit. Therefore, the rated voltage of the switches in the second switching circuit can correspond to the voltage at the second capacitor unit divided by the number of switches in the second switching circuit.

[0065] The voltage at a capacitor can also be called the voltage across the capacitor or the voltage across the capacitor.

[0066] In a first aspect embodiment, the resonant capacitor and the resonant inductor are connected in series between the midpoint of the series connection of the two switching units of the first switching circuit and the midpoint of the series connection of the two switching units of the second switching circuit. Optionally, in a first aspect embodiment, the resonant capacitor is electrically connected between the midpoint of the series connection of the two switching units of the first switching circuit and the midpoint of the series connection of the two switching units of the second switching circuit, and the resonant inductor is electrically connected between the midpoint of the series connection of the two capacitor units and the midpoint of the series connection of the two switching circuits.

[0067] Resonant capacitors and inductors enable DC / DC power converters to operate at resonant frequencies, thus incurring almost no switching losses. Resonant circuits enable soft switching and provide high efficiency.

[0068] When the resonant capacitor and resonant inductor are connected in series between the midpoint of the series connection of the two switching units of the first switching circuit and the midpoint of the series connection of the two switching units of the second switching circuit, the first switching circuit can be connected in parallel to the first capacitor unit and the second switching circuit can be connected in parallel to the second capacitor unit.

[0069] When a resonant capacitor and a resonant inductor are connected in series between the midpoint of the series connection of the two switching units in the first switching circuit and the midpoint of the series connection of the two switching units in the second switching circuit, the midpoint of the series connection of the two capacitor units and the midpoint of the series connection of the two switching circuits can be electrically connected to each other.

[0070] In a first aspect embodiment, the input includes two input terminals, and the output includes two output terminals. A first input terminal and a first output terminal are electrically connected to one end of a series connection of two capacitor cells and one end of a series connection of two switching circuits. A second input terminal is connected to the midpoint of the series connection of the two capacitor cells. A second output terminal is connected to the other end of the series connection of the two capacitor cells and the other end of the series connection of the two switching circuits.

[0071] Both the first switching circuit and the first capacitor unit can be connected to the first input terminal and the first output terminal. Both the second switching circuit and the second capacitor unit can be connected to the second output terminal. Specifically, the first capacitor unit can be connected between the first input terminal and the second input terminal. The second capacitor unit can be connected between the second input terminal and the second output terminal. The first input terminal and the first output terminal can be interconnected.

[0072] In an embodiment of the first aspect, the output includes a third output terminal. When the resonant capacitor and resonant inductor are connected in series, the third output terminal can be electrically connected to the midpoint of the series connection of the two capacitor units and the midpoint of the series connection of the two switching circuits. Alternatively, when the resonant inductor is connected between the midpoint of the series connection of the two capacitor units and the midpoint of the series connection of the two switching circuits, the third output terminal can be electrically connected to the midpoint of the series connection of the two capacitor units.

[0073] An optional third output terminal can be used for grounding requirements. This optional third output terminal allows for the provision of two output voltages at the output: a first output voltage between the first and third output terminals, and a second output voltage between the third and second output terminals. The first and second output voltages are less than the output voltage between the first and second output terminals.

[0074] In an embodiment of the first aspect, the DC / DC power converter includes a control unit. The control unit is configured to selectively and complementaryly switch a switching unit of a first switching circuit between an on state and an off state with a 50% duty cycle. Optionally, the control unit is configured to selectively and complementaryly switch a switching unit of a first switching circuit and a second switching circuit between an on state and an off state with a 50% duty cycle.

[0075] The DC / DC power converter is based on the concept of a resonant balancer (i.e., the DC / DC power converter includes a resonant circuit for DC / DC conversion), and therefore, the control unit does not require closed-loop control to operate the DC / DC power converter. Thus, the DC / DC power converter according to the embodiment of the first aspect is advantageous due to the reduced size, complexity, and cost of controlling the DC / DC power converter (especially the corresponding controllable semiconductor switch of the DC / DC power converter).

[0076] The control unit may include or correspond to a microcontroller, controller, microprocessor, processor, field programmable gate array (FPGA), application specific integrated circuit (ASIC), or any combination of the above components.

[0077] When the control unit is used to complementary switch the switching units of the second switching circuit, the switches in the second switching circuit are controllable semiconductor switches. The control unit can be used to control the switching of the switching units in feedforward control (open-loop control). That is, the control unit can be used to control the switching of the switching units without feedback control (closed-loop control).

[0078] The switching unit is in a conducting state when all switches in the switching unit are in the ON state. Conversely, the switching unit is in a non-conducting state when all switches in the switching unit are in the OFF state. The switching unit is in a steady state when it is in either the ON or OFF state. The ON state can also be called the on state or the closed state. The OFF state can also be called the off state or the closed state.

[0079] When the control unit is used to complementaryly switch the switching units of the first switching circuit and the second switching circuit, the control unit can be used to switch the switching units so that switching units at the same position in the switching circuit switch together. That is, the control unit can be used to switch the first switching unit of the first switching circuit and the first switching unit of the second switching circuit from one state to another state, and simultaneously switch the second switching unit of the first switching circuit and the second switching unit of the second switching circuit from the aforementioned other state to the aforementioned one state.

[0080] The second switching unit of the first switching circuit is connected to the midpoint of the series connection of the two switching circuits, and the first switching unit of the first switching circuit is connected to the midpoint via the second switching unit. The first switching unit of the second switching circuit is connected to the midpoint of the series connection of the two switching circuits, and the second switching unit of the second switching circuit is connected to the midpoint via the first switching unit. One of the aforementioned states can be a conducting state, and the other state can be a non-conducting state. Optionally, one of the aforementioned states can be a non-conducting state, and the other state can be a conducting state.

[0081] The control unit can be used to complementaryly switch the switching unit of the first switching circuit between an on state and an off state with a 50% duty cycle. Optionally, the control unit can be used to complementaryly switch the switching unit of the first switching circuit and the second switching circuit between an on state and an off state with a 50% duty cycle.

[0082] This is advantageous because when the switch of the second switching circuit is a controllable semiconductor switch, switching the switching unit of the first switching circuit and optionally the switching unit of the second switching circuit with a constant duty cycle of 50% is not required, complex control of the control unit is not needed.

[0083] In an embodiment of the first aspect, the control unit is used to switch the corresponding switching unit of the corresponding switching circuit between an on state and an off state by sequentially switching the switch of each switching unit.

[0084] This allows the use of low-voltage semiconductor devices, and thus low-cost controllable switches, to implement the controllable switching of the corresponding switching circuits without the need for pre-matching of the controllable semiconductor switches for similar switching times, or complex gate drive circuits to provide drive and control signals to jointly switch the controllable semiconductor switches of each switching unit of the corresponding switching circuit. This reduces the complexity, cost, and number of components in implementing the DC / DC power converter according to the first aspect.

[0085] In other words, the control unit can be used to switch the corresponding switching unit of the corresponding switching circuit between the on and off states by sequentially switching the switches of each switching unit.

[0086] The term "corresponding switching circuit" refers to each switching circuit having switching units, each comprising two or more controllable semiconductor switches. That is, in the case where two or more switches in each switching unit of the switching circuit correspond to two or more controllable semiconductor switches, the two or more switches in each switching unit of the switching circuit can be controlled by a control unit.

[0087] That is, the control unit can be used to control the switching of each switching unit of the corresponding switching circuit between the on and off states, so that only one switch of the corresponding switching unit is switched at any given time.

[0088] For example, a control unit can be used to control the corresponding switching unit of a corresponding switching circuit to switch from the on state to the off state by sequentially switching the switches of each switching unit from the on state to the off state. That is, at any given time, the control unit switches only one switch of the corresponding switching unit from the on state to the off state to switch the corresponding switching unit from the on state to the off state. Therefore, the control unit can be used to control the corresponding switching unit of a corresponding switching circuit to switch from the off state to the on state by sequentially switching the switches of each switching unit from the off state to the on state. That is, at any given time, the control unit switches only one switch of the corresponding switching unit from the off state to the on state to switch the corresponding switching unit from the off state to the on state.

[0089] The corresponding switching circuit corresponds to the first switching circuit. Optionally, the corresponding switching circuit corresponds to both the first and second switching circuits.

[0090] In a first aspect of the implementation, the control unit is used to complementary switch the two switching units of the corresponding switching circuit between an on state and an off state by alternately switching the switches of the two switching units of the corresponding switching circuit.

[0091] For the reasons described above, this reduces the complexity, cost, and number of components required to implement the DC / DC power converter according to the first aspect.

[0092] The corresponding switching circuit corresponds to the first switching circuit. Optionally, the corresponding switching circuit corresponds to both the first and second switching circuits.

[0093] In an embodiment of the first aspect, the control unit is configured to switch each of the two switching units of the corresponding switching circuit from an on state to a non-on state as follows: according to the position of the two or more switches of the corresponding switching unit in the series connection, the two or more switches of the corresponding switching unit are sequentially switched from an on state to a non-on state, such that the switch of the corresponding switching unit that is farthest from the midpoint of the series connection of the two switching units of the corresponding switching circuit is switched from an on state to a non-on state first.

[0094] The corresponding switching circuit corresponds to the first switching circuit. Optionally, the corresponding switching circuit corresponds to both the first and second switching circuits.

[0095] The term "farthest" should be understood as "farthest in terms of nodes". That is, "the switch whose corresponding switching unit is farthest from the midpoint of the series connection of the two switching units" should be understood as "the switch whose corresponding switching unit is farthest from the midpoint of the series connection of the two switching units in terms of nodes between the switch and the midpoint".

[0096] In a first aspect of the implementation, the control unit is configured to switch each of the two switching units of the corresponding switching circuit from a non-conducting state to a conducting state as follows: according to the position of the two or more switches of the corresponding switching unit in the series connection, the two or more switches of the corresponding switching unit are sequentially switched from a non-conducting state to a conducting state, such that the switch at the midpoint of the series connection of the two switching units of the corresponding switching circuit connected to the corresponding switching unit is switched from a non-conducting state to a conducting state first.

[0097] The corresponding switching circuit corresponds to the first switching circuit. Optionally, the corresponding switching circuit corresponds to the first switching circuit and the second switching circuit. Each switching circuit includes a first switching unit and a second switching unit.

[0098] The second switching unit of the first switching circuit is connected to the midpoint of the series connection of the two switching circuits, and the first switching unit of the first switching circuit is connected to this midpoint via the second switching unit. The first switching unit of the second switching circuit is connected to the midpoint of the series connection of the two switching circuits, and the second switching unit of the second switching circuit is connected to this midpoint via the first switching unit. That is, between the two ends of the series connection of the two switching circuits, starting from one of the two ends, the first switching unit of the first switching circuit is followed by the second switching unit of the first switching circuit, and the second switching unit of the first switching circuit is followed by the first switching unit of the second switching circuit. The first switching unit of the second switching circuit is followed by the second switching unit of the second switching circuit.

[0099] When the switch in the first switching circuit is a controllable semiconductor switch (e.g., a transistor (e.g., an IGBT or MOSFET)) and the switch in the second switching circuit is an uncontrollable semiconductor switch (e.g., a diode), the following holds true:

[0100] The control unit can be used to switch a first switching unit of the first switching circuit from an on state to a non-conducting state, and to switch a second switching unit of the first switching circuit from a non-conducting state to an on state, by alternately switching the switches of the first switching unit and the second switching unit, such that...

[0101] First, the switch of the first switching unit switches from the ON state to the OFF state, and then the switch of the second switching unit switches from the OFF state to the ON state.

[0102] -The switches of the first switching unit sequentially switch from the on state to the off state, and

[0103] - The switches of the second switching unit are switched sequentially from the non-conducting state to the conducting state.

[0104] Additionally or optionally, the control unit may be configured to switch a first switching unit of the first switching circuit from a non-conducting state to a conducting state, and to switch a second switching unit of the first switching circuit from a conducting state to a non-conducting state, by alternately switching the switches of the first switching unit and the second switching unit, such that...

[0105] First, the switch of the second switching unit switches from the ON state to the OFF state, and then the switch of the first switching unit switches from the OFF state to the ON state.

[0106] - The switches of the second switching unit sequentially switch from the on state to the off state, and

[0107] - The switches of the first switching unit are switched sequentially from the non-conducting state to the conducting state.

[0108] When the switches in the first and second switching circuits are controllable semiconductor switches (e.g., transistors (e.g., IGBTs or MOSFETs)), the following holds true:

[0109] The control unit can be used to switch the first switching unit from an on state to a non-conducting state and the second switching unit from a non-conducting state to an on state by alternately switching the switches of the first and second switching units, such that...

[0110] First, the switch of each first switching unit switches from the ON state to the OFF state (the positions of the switches in the first switching units correspond to each other). Then, the switch of each second switching unit switches from the OFF state to the ON state (the positions of the switches in the second switching units correspond to each other).

[0111] - The switch of each first switching unit sequentially switches from the on state to the off state, and

[0112] - The switches of each second switching unit switch sequentially from the non-conducting state to the conducting state.

[0113] Additionally or optionally, the control unit may be configured to switch the first switching unit from a non-conducting state to a conducting state and the second switching unit from a conducting state to a non-conducting state by alternately switching the switches of the first and second switching units, such that...

[0114] First, the switch of each second switching unit switches from the ON state to the OFF state (the positions of the switches in the second switching units correspond to each other). Then, the switch of each first switching unit switches from the OFF state to the ON state (the positions of the switches in the first switching units correspond to each other).

[0115] - The switches of each second switching unit sequentially switch from the on state to the off state, and

[0116] - The switch of each first switching unit switches sequentially from the non-conducting state to the conducting state.

[0117] In an embodiment of the first aspect, the control unit is used to switch the switching unit between an on state and an off state at a switching frequency (also called a switching frequency) less than or equal to the resonant frequency of the resonant circuit.

[0118] The switching frequency can be matched with the resonant frequency of the resonant circuit. The resonant frequency is determined by the following:

[0119] in

[0120] f res It is the resonant frequency of the resonant circuit, C. r It is the resonant capacitor of the resonant circuit, and L r It is the resonant inductance of a resonant circuit.

[0121] In order to implement the DC / DC power converter according to the first aspect of this disclosure, some or all of the embodiments and optional features of the first aspect as described above can be combined with each other.

[0122] A second aspect of this disclosure provides a method for controlling the switching of a DC / DC power converter according to the first aspect or any embodiment thereof, wherein a control unit optionally complementaryly switches switching units of a first switching circuit between an on state and an off state with a 50% duty cycle. Optionally, the control unit optionally complementaryly switches switching units of a first switching circuit and a second switching circuit between an on state and an off state with a 50% duty cycle.

[0123] The control unit can be an external control unit or the control unit of a DC / DC power converter. The control unit may include or correspond to a microcontroller, controller, microprocessor, processor, field-programmable gate array (FPGA), application-specific integrated circuit (ASIC), or any combination of the above components.

[0124] In the second aspect of the implementation, the control unit switches the corresponding switching unit of the corresponding switching circuit between an on state and an off state by sequentially switching the switch of each switching unit.

[0125] In the second aspect of the implementation, the control unit alternately switches the two switching units of the corresponding switching circuit between the on and off states by switching the switches of the two switching units of the corresponding switching circuit alternately.

[0126] In the second aspect of the implementation, the control unit switches each of the two switching units of the corresponding switching circuit from the on state to the off state as follows: according to the position of the two or more switches of the corresponding switching unit in the series connection, the two or more switches of the corresponding switching unit are switched from the on state to the off state in sequence, such that the switch of the corresponding switching unit that is farthest from the midpoint of the series connection of the two switching units of the corresponding switching circuit switches from the on state to the off state first.

[0127] In the second aspect of the implementation, the control unit switches each of the two switching units of the corresponding switching circuit from a non-conducting state to a conducting state as follows: according to the position of the two or more switches of the corresponding switching unit in the series connection, the two or more switches of the corresponding switching unit are switched from a non-conducting state to a conducting state in sequence, such that the switch at the midpoint of the series connection of the two switching units of the corresponding switching circuit connected to the corresponding switching unit is switched from a non-conducting state to a conducting state first.

[0128] In the second aspect of the implementation, the control unit switches the switching unit between the on and off states at a switching frequency less than or equal to the resonant frequency of the resonant circuit.

[0129] The description of the implementation method and optional features of the DC / DC power converter according to the first aspect is accordingly applicable to the method according to the second aspect.

[0130] The method and its implementation methods and optional features of the second aspect achieve the same advantages as the DC / DC power converter and its corresponding implementation methods and optional features of the first aspect.

[0131] In order to implement the method according to the second aspect of this disclosure, some or all of the embodiments and optional features of the second aspect as described above may be combined with each other.

[0132] A third aspect of this disclosure provides a DC / DC power converter arrangement. This arrangement includes a cascade of multiple DC / DC power converters. Each DC / DC power converter includes two switching circuits connected in series, two capacitor cells connected in series, and a resonant circuit including a resonant capacitor and a resonant inductor. Each capacitor cell includes one or more capacitors, and the series connection of two capacitor cells is connected in parallel to the series connection of two switching circuits. The resonant circuit is connected to the two switching circuits. A first capacitor cell of the two capacitor cells is connected in parallel to the input of the DC / DC power converter, and the series connection of the two switching circuits is connected in parallel to the output of the DC / DC power converter. The output of the first DC / DC power converter is electrically connected to the input of a second DC / DC power converter, such that a first capacitor cell of the second DC / DC power converter is connected in parallel to a second capacitor cell of the two capacitor cells of the first DC / DC power converter.

[0133] The first switching circuit in the two switching circuits of the DC / DC power converter can be electrically connected to one side of the first capacitor unit of the DC / DC power converter, which is opposite to the other side of the first capacitor unit, and the other side of the first capacitor unit is connected to the second capacitor unit in the two capacitor units of the DC / DC power converter.

[0134] The first capacitor unit of the second DC / DC power converter and the second capacitor unit of the first DC / DC power converter can be implemented by a single capacitor unit connected in parallel corresponding to these two capacitor units. In other words, the parallel connection of the first capacitor unit of the second DC / DC power converter and the second capacitor unit of the first DC / DC power converter can be replaced by a capacitor unit corresponding to this parallel connection.

[0135] A DC / DC power converter arrangement is used to convert a first voltage (input voltage) at the input of the DC / DC power converter arrangement into a second voltage (output voltage) at the output of the DC / DC power converter arrangement, wherein the second voltage is a multiple of the first voltage. Specifically, the second voltage is a multiple of the first voltage and can be twice the first voltage. The second voltage can be an integer multiple of the first voltage.

[0136] According to the implementation, the second voltage can be an integer multiple of the first voltage, wherein the integer multiple is one more than the number of DC / DC power converters arranged in the DC / DC power converter configuration.

[0137] The input of a DC / DC power converter arrangement can correspond to the input of the first DC / DC power converter in a plurality of DC / DC power converters.

[0138] In a third aspect of the implementation, the input of each of the plurality of DC / DC power converters is connected to the output of the corresponding preceding DC / DC power converter, such that the first capacitor cell of the corresponding other DC / DC power converter is connected in parallel to the second capacitor cell of the corresponding preceding DC / DC power converter.

[0139] The first capacitor unit of a corresponding other DC / DC power converter and the second capacitor unit of a corresponding preceding DC / DC power converter can be implemented by a single capacitor unit corresponding to these two capacitor units connected in parallel. In other words, the parallel connection of the first capacitor unit of a corresponding other DC / DC power converter and the second capacitor unit of a corresponding preceding DC / DC power converter can be replaced by a capacitor unit corresponding to that parallel connection.

[0140] In an embodiment of the third aspect, one or more of the plurality of DC / DC power converters correspond to the DC / DC power converter according to the first aspect or any embodiment thereof.

[0141] A DC / DC power converter arrangement may include a control unit for controlling a plurality of DC / DC power converters. Specifically, the control unit may be used to perform a method according to the second aspect or any embodiment thereof to control the plurality of DC / DC power converters.

[0142] The control unit of the DC / DC power converter arrangement may include or correspond to a microcontroller, controller, microprocessor, processor, field-programmable gate array (FPGA), application-specific integrated circuit (ASIC), or any combination of the above components.

[0143] The control unit may correspond to the control unit of one of a plurality of DC / DC power converters, wherein the aforementioned DC / DC power converter is a DC / DC power converter according to the first aspect or any embodiment thereof.

[0144] In the case where two or more DC / DC power converters in a DC / DC power converter arrangement include control units for controlling the respective DC / DC power converters, the control units of the two or more DC / DC power converters can be used to communicate with each other.

[0145] According to embodiments of the present disclosure, each of a plurality of DC / DC power converters may correspond to a DC / DC power converter according to the first aspect or any embodiment thereof.

[0146] The implementation method and optional features of the DC / DC power converter according to the first aspect are correspondingly applicable to the arrangement of DC / DC power converters according to the third aspect (in particular, one or more of a plurality of DC / DC power converters arranged according to the third aspect).

[0147] The DC / DC power converter arrangement, its implementation method, and optional features of the third aspect achieve the same advantages as the DC / DC power converter, its corresponding implementation method, and corresponding optional features of the first aspect.

[0148] To implement the DC / DC power converter arrangement of the third aspect of this disclosure, some or all of the embodiments and optional features of the third aspect as described above can be combined with each other.

[0149] The fourth aspect of this disclosure provides a system.

[0150] The system includes a DC / DC power converter according to the first aspect or any embodiment thereof, and a power supply connected to the input of the DC / DC power converter. The power supply provides a DC input voltage to the input of the DC / DC power converter, and the DC / DC power converter converts the DC input voltage into a DC output voltage, wherein the DC output voltage is a multiple of the DC input voltage. Specifically, the DC output voltage may be twice the DC input voltage.

[0151] In other words, a DC / DC power converter is used to convert a DC input voltage to a DC output voltage, where the DC output voltage level is greater than the DC input voltage level. Specifically, the DC output voltage level can be twice the DC input voltage level.

[0152] Optionally, the system includes a DC / DC power converter arrangement according to the third aspect or any embodiment thereof, and a power supply connected to the input of the DC / DC power converter arrangement. Specifically, the power supply may be connected to the input of a first DC / DC power converter in the DC / DC power converter arrangement. The power supply is used to provide a DC input voltage to the input of the DC / DC power converter arrangement, and the DC / DC power converter arrangement is used to convert the DC input voltage into a DC output voltage, wherein the DC output voltage is a multiple of the DC input voltage. Specifically, the DC output voltage is a multiple of the DC input voltage and may be twice the DC input voltage.

[0153] According to the implementation, the DC output voltage (of the DC / DC power converter arrangement) can be an integer multiple of the DC input voltage, wherein the integer multiple is one more than the number of DC / DC power converters in the DC / DC power converter arrangement.

[0154] In other words, the DC / DC power converter arrangement is used to convert a DC input voltage into a DC output voltage, wherein the DC output voltage level is a multiple of the DC input voltage level, and optionally twice the DC input voltage level. According to an embodiment, the DC output voltage level can be an integer multiple of the DC input voltage level, wherein this integer multiple is one more than the number of DC / DC power converters in the DC / DC power converter arrangement.

[0155] The terms “level” and “voltage level” are used as synonyms.

[0156] The power supply may include or correspond to

[0157] - Arranged in front of the DC / DC power converter, and / or

[0158] - AC / DC power converter, and / or

[0159] - Battery (optionally, rechargeable), and / or

[0160] - A solar photovoltaic (PV) system with one or more solar PV panels, and / or

[0161] - One or more solar PV strings, and / or

[0162] - Wind power systems, etc.

[0163] The arrangement of the DC / DC power converter can correspond to the DC / DC power converter according to the first aspect or any embodiment thereof, or to the DC / DC power converter arrangement according to the third aspect or any embodiment thereof.

[0164] In a fourth aspect of the implementation, the system may further include circuitry connected to the output of the DC / DC power converter. Optionally, the system may also include circuitry connected to the output of the DC / DC power converter array. In particular, the circuitry may be connected to the output of the last DC / DC power converter in a cascade of DC / DC power converters in the DC / DC power converter array.

[0165] The circuit may include or correspond to

[0166] - DC / DC power converter arrangement, and / or

[0167] -DC / AC power converter, and / or

[0168] -DC transmission system, and / or

[0169] - Solid-state transformers, and / or

[0170] - Electrical load.

[0171] The DC / DC power converter arrangement may correspond to the DC / DC power converter according to the first aspect or any embodiment thereof, or to the DC / DC power converter arrangement according to the third aspect or any embodiment thereof.

[0172] The embodiments and optional features of the DC / DC power converter according to the first aspect are correspondingly applicable to the system according to the fourth aspect, and in particular to the DC / DC power converter arrangement of the system according to the fourth aspect. The embodiments and optional features of the DC / DC power converter arrangement according to the third aspect are correspondingly applicable to the system according to the fourth aspect, and in particular to the DC / DC power converter arrangement of the system according to the fourth aspect.

[0173] The system of the fourth aspect, its implementation method, and optional features achieve the same advantages as the DC / DC power converter of the first aspect, its corresponding implementation method, and corresponding optional features.

[0174] To implement the system of the fourth aspect of this disclosure, some or all of the embodiments and optional features of the fourth aspect as described above may be combined with each other.

[0175] It should be noted that all devices, elements, units, and apparatuses described in this application can be implemented in software or hardware elements or any combination thereof. All steps performed by the various entities described in this application, and the functions described as being performed by the various entities, are intended to indicate that the various entities are suitable for or used to perform the various steps and functions. Even in the following description of specific embodiments, where a particular function or step to be performed by an external entity is not reflected in the description of the specific detailed elements of the entity performing that particular step or function, it should be apparent to those skilled in the art that these methods and functions can be implemented in the corresponding software or hardware elements, or any combination thereof. Attached Figure Description

[0176] The above aspects and implementation methods will be explained below in conjunction with the accompanying drawings and in the description of specific embodiments, wherein...

[0177] Figure 1 An exemplary DC / DC power converter including a resonant circuit is shown.

[0178] Figure 2(A) illustrates a DC / DC power converter according to an embodiment of the present invention.

[0179] Figure 2(B) illustrates an optional control unit for a DC / DC power converter according to an embodiment of the present invention.

[0180] Figures 3(A) and 3(B) respectively illustrate DC / DC power converters according to embodiments of the present invention.

[0181] Figures 4(A) and 4(B) respectively illustrate DC / DC power converters according to embodiments of the present invention.

[0182] Figures 5(A) and 5(B) respectively illustrate DC / DC power converters according to embodiments of the present invention.

[0183] Figure 6 Different embodiments of a switching circuit for a DC / DC power converter according to an embodiment of the present invention are shown.

[0184] Figure 7 The different states of the DC / DC power converter according to the embodiment of the invention are shown, particularly the two steady-state and two transient switching states, when the DC / DC power converter switches between two steady states according to the embodiment of the invention.

[0185] Figures 8(A) and 8(B) respectively illustrate the arrangement of the DC / DC power converter according to an embodiment of the present invention.

[0186] Figures 9(A) and 9(B) respectively illustrate the arrangement of the DC / DC power converter according to an embodiment of the present invention.

[0187] Figure 10 A system according to an embodiment of the present invention is shown.

[0188] In the accompanying drawings, corresponding elements are labeled with the same reference numerals. Detailed Implementation

[0189] Figure 2(A) illustrates a DC / DC power converter according to an embodiment of the present invention.

[0190] The above description of the DC / DC power converter of the first aspect or any embodiment thereof applies accordingly to the DC / DC power converter 4 of FIG2(A).

[0191] The DC / DC power converter 4 in Figure 2(A) includes a resonant circuit 3, two switching circuits 1 and 2 connected in series, and two capacitor units C1 and C2 connected in series. The series connection of the two capacitor units C1 and C2 is connected in parallel to the series connection of the two switching circuits 1 and 2. The resonant circuit 3 is electrically connected to the two switching circuits 1 and 2.

[0192] The DC / DC power converter 4 also includes inputs with two input terminals IN1 and IN2 and outputs with two output terminals OUT1 and OUT2. The DC / DC power converter 4 is used to convert the voltage Vin at the input to the voltage Vout at the output, wherein the voltage Vout at the output is a multiple of the voltage Vin at the input.

[0193] The first capacitor unit C1 of the two capacitor units C1 and C2 is connected in parallel to the input of the DC / DC power converter 4, such that the voltage Vin that can be received at the input of the DC / DC power converter 4 corresponds to the voltage across the first capacitor unit C1. The series connection of the two switching circuits 1 and 2 is connected in parallel to the output of the DC / DC power converter 4, such that the voltage Vout at the output of the DC / DC power converter 4 corresponds to the voltage across the series connection of the two switching circuits 1 and 2.

[0194] In the two switching circuits 1 and 2, the first switching circuit 1 is connected to one side of the first capacitor unit C1, and this side of the first capacitor unit C1 is opposite to the other side of the first capacitor unit C1. This other side of the first capacitor unit C1 is connected to the second capacitor unit C2 in the two capacitor units C1 and C2. Therefore, in the two switching circuits 1 and 2, the second switching circuit 2 is connected to one side of the second capacitor unit C2, and this side of the second capacitor unit C2 is opposite to the other side of the second capacitor unit C2. This other side of the second capacitor unit C2 is connected to the first capacitor unit C1.

[0195] The resonant circuit 3 includes a resonant capacitor Cr (not shown in Figure 2(A)) and a resonant inductor Lr (not shown in Figure 2(A)). According to one option, the resonant capacitor Cr and the resonant inductor Lr can be connected in series, wherein this series connection can be connected on one side to the first switching circuit 1 and on the other side to the second switching circuit 2. This option is shown in Figure 3(A). In this case, the midpoint of the series connection of the two capacitor units C1, C2 and the midpoint of the series connection of the two switching circuits 1, 2 are interconnected (as shown in Figures 2(A) and 3(A)). According to another option, the resonant capacitor Cr can be connected on one side to the first switching circuit 1 and on the other side to the second switching circuit 2. Additionally, the resonant inductor Lr can be connected between the midpoint of the series connection of the two capacitor units C1, C2 and the midpoint of the series connection of the two switching circuits 1, 2. This option is shown in Figure 3(B). In this case, the midpoint of the series connection of the two capacitor units C1 and C2 is connected to the midpoint of the series connection of the two switching circuits 1 and 2 via the resonant inductor Lr (not shown in Figure 2(A), but shown in Figure 3(B)).

[0196] The first switching circuit 1 includes two switching units 11 and 12 connected in series. The second switching circuit 2 includes two switching units 21 and 22 connected in series. Therefore, the four switching units 11, 12, 21, and 22 are connected in series with each other. Each of the four switching units 11, 12, 21, and 22 includes two or more switches connected in series. That is, the switches of the two switching circuits 1 and 2 (the four switching units 11, 12, 21, and 22) are connected in series.

[0197] Two or more switches in each switching unit 11, 12 of the first switching circuit 1 are controllable semiconductor switches (e.g., transistors). Therefore, the switching of the switches in the first switching circuit 1 can be actively controlled by a control unit (this is indicated in Figure 2(A) by arrows at each switch of the first and second switching units 11, 12 of the first switching circuit 1). For example, the switches in each switching unit 11, 12 of the first switching circuit 1 can be one or more bipolar junction transistors (BJTs), one or more field-effect transistors (FETs) (e.g., one or more metal-oxide-semiconductor field-effect transistors (MOSFETs)), and / or one or more insulated-gate bipolar transistors (IGBTs).

[0198] Since the switch of the first switching circuit 1 is a controllable semiconductor switch, the first capacitor unit C1 includes two or more capacitors C11, ..., C1n (n≥2), and the first switching circuit 1 includes one or more diode units D11. One or more diode units D11 electrically connect the first capacitor unit C1 to the two switching units 11 and 12 of the first switching circuit 1. The second capacitor unit C2 includes one or more capacitors C21.

[0199] Each switching unit 21, 22 of the second switching circuit 2 can be an uncontrollable semiconductor switch (e.g., a diode) or a controllable semiconductor switch (e.g., a transistor). The first option described above is shown in FIG. 5, and the second option described above is shown in FIG. 4. When the switch of the second switching circuit 2 is a controllable semiconductor switch, the second capacitor unit C2 includes two or more capacitors and the second switching circuit 2 includes one or more diode units, which electrically connect the second capacitor unit C2 to the two switching units 21, 22 of the second switching circuit 2 (not shown in FIG. 2(A), but shown in FIG. 4).

[0200] The capacitance of each of the two or more capacitors C11, ..., Cn in the first capacitor unit C1 and one or more capacitors C21 in the second capacitor unit C2 is greater than the capacitance of the resonant capacitor Cr in the resonant circuit 3, so that these capacitors do not affect the resonance of the resonant circuit 3.

[0201] The number of switches in each switching unit of the first switching circuit 1 and / or the second switching circuit 2 can be the same. The switches (which are controllable semiconductor switches) in each switching unit 11 and 12 of the first switching circuit 1 can have the same switch type. The switches in each switching unit 21 and 22 of the second switching circuit 2 can have the same switch type.

[0202] The first input terminal IN1 and the first output terminal OUT1 are connected to each other. The second input terminal IN2 is connected to the midpoint between the series connection of two capacitor units C1 and C2. The series connection of the two capacitor units C1 and C2 is connected between the first input terminal IN1 and the second output terminal OUT2, and the series connection of the two switching circuits 1 and 2 is connected between the first output terminal OUT1 and the second output terminal OUT2.

[0203] According to Figure 2(A), each switching circuit 1, 2 includes an X terminal, a Y terminal, and a Z terminal. The X terminal of the first switching circuit 1 is connected to the first input terminal IN1 and the first output terminal OUT1. The Y terminal of the first switching circuit 1 is connected to the X terminal of the second switching circuit 2. The Y terminal of the second switching circuit 2 is connected to the second output terminal OUT2 and one side of the second capacitor unit C2, which is opposite to the side of the second capacitor unit C2 connected to the first capacitor unit C1. The Z terminal of the first switching circuit 1 and the Z terminal of the second switching circuit 2 are connected to the resonant circuit 3. As shown in Figure 2(A), the series connection of the two switching units 11 and 12 of the first switching circuit 1 is connected between the X terminal and the Y terminal of the first switching circuit 1. The Z terminal of the first switching circuit 1 is connected to the midpoint of the series connection of the two switching units 11 and 12 of the first switching circuit 1. Further, as shown in Figure 2(A), the series connection of the two switching units 21 and 22 of the second switching circuit 2 is connected between the X terminal and the Y terminal of the second switching circuit 2. The Z-terminal of the second switching circuit 2 is connected to the midpoint of the series connection of the two switching units 21 and 22 of the second switching circuit 2.

[0204] The topmost switch unit 11 in the series connection of the two switch units 11 and 12 of the first switching circuit 1 can be referred to as the first switch unit of the first switching circuit 1. Among the two switch units 11 and 12 of the first switching circuit 1, the topmost switch unit 11 (first switch unit 11) is furthest from the midpoint of the series connection of the two switch circuits 1 and 2. The bottommost switch unit 12 in the series connection of the two switch units 11 and 12 of the first switching circuit 1 can be referred to as the second switch unit of the first switching circuit 1. The bottommost switch unit 12 (second switch unit 12) of the first switching circuit 1 is connected to the midpoint of the series connection of the two switch circuits 1 and 2. The first switch unit 11 of the first switching circuit 1 is connected to the midpoint of the series connection of the two switch circuits 1 and 2 via the second switch unit 12 of the first switching circuit 1.

[0205] The topmost switch unit 21 of the series connection of the two switch units 21 and 22 in the second switching circuit 2 can be referred to as the first switch unit of the second switching circuit 2. The topmost switch unit 21 (first switch unit 21) of the second switching circuit 2 is connected to the midpoint of the series connection of the two switch circuits 1 and 2. The bottommost switch unit 22 of the series connection of the two switch units 21 and 22 in the second switching circuit 2 can be referred to as the second switch unit of the second switching circuit 2. Among the two switch units 21 and 22 in the second switching circuit 2, the bottommost switch unit 22 (second switch unit 22) of the second switching circuit 2 is furthest from the midpoint of the series connection of the two switch circuits 1 and 2. The second switch unit 22 of the second switching circuit 2 is connected to the midpoint of the series connection of the two switch circuits 1 and 2 via the first switch unit 21 of the second switching circuit 2.

[0206] Optionally, the DC / DC power converter 4 may include a control unit for complementary switching of the switching units 11, 12 of the first switching circuit 1 between an on state and an off state. An example of such a control unit is shown in FIG2(B). According to an embodiment, the control unit is used to complementary switch the switching units 11, 12 of the first switching circuit 1 with a 50% duty cycle.

[0207] When the switch in the second switching circuit 2 is a controllable semiconductor switch, an optional control unit can be used to complementaryly switch the switching units 11, 12, 21, and 22 of the first switching circuit 1 and the second switching circuit 2 between an on state and a non-conducting state. The optional control unit can be used to switch the first switching units 11 and 21 of the first and second switching circuits 1 and 2 from an on state to a non-conducting state, while switching the second switching units 12 and 22 of the first and second switching circuits 1 and 2 from a non-conducting state to an on state. Correspondingly, the optional control unit can be used to switch the first switching units 11 and 21 of the first and second switching circuits 1 and 2 from a non-conducting state to an on state, while switching the second switching units 12 and 22 of the first and second switching circuits 1 and 2 from an on state to a non-conducting state. According to an embodiment, the control unit is used to complementaryly switch the switching units 11, 12, 21, and 22 of the first and second switching circuits 1 and 2 with a 50% duty cycle.

[0208] The control unit can be used to switch the corresponding switching units of the first switching circuit 1 and optionally the second switching circuit 2 between an on state and an off state by sequentially switching the switches (controllable semiconductor switches) of each switching unit.

[0209] The following combination Figure 7 (A) to Figure 7 (J) describes an example of switching the first switching circuit 1 and optionally the second switching circuit 2.

[0210] Figure 2(B) illustrates an optional control unit for a DC / DC power converter according to an embodiment of the present invention.

[0211] The description of the control unit of the DC / DC power converter according to the first aspect or any embodiment thereof applies to the control unit 5 of FIG2(B). The control unit 5 of FIG2(B) is used to perform the method according to the second aspect or any embodiment thereof.

[0212] The control unit 5 may include or correspond to a microcontroller, controller, microprocessor, processor, field-programmable gate array (FPGA), application-specific integrated circuit (ASIC), or any combination of the above components.

[0213] Control unit 5 is used to provide control signals CS111, ..., CS11 to each controllable semiconductor switch of the first switching circuit 1 for controlling the switching of the controllable semiconductor switches. n CS121, ..., CS12 n When the switches in the second switching circuit 2 are also controllable semiconductor switches, the control unit 5 can be used to provide control signals to each controllable semiconductor switch in the second switching circuit 2 for controlling the switching of the controllable semiconductor switches.

[0214] Figures 3(A) and 3(B) respectively illustrate DC / DC power converters according to embodiments of the present invention.

[0215] The DC / DC power converter 4 in Figure 3(A) and Figure 3(B) corresponds to the DC / DC power converter 4 in Figure 2(A). Therefore, the description of the DC / DC power converter 4 in Figure 2(A) is applicable accordingly to the DC / DC power converters 4 in Figures 3(A) and 3(B). Therefore, the following mainly describes the additional features of the DC / DC power converters 4 in Figures 3(A) and 3(B) relative to the DC / DC power converter in Figure 2. Figures 3(A) and 3(B) show two implementations of the resonant circuit 3.

[0216] According to Figure 3(A), the resonant capacitor Cr and the resonant inductor Lr of the resonant circuit 3 are connected in series. One side of the series connection of the resonant capacitor Cr and the resonant inductor Lr is connected to the first switching circuit 1 (specifically to the Z terminal of the first switching circuit 1), and the other side is connected to the second switching circuit 2 (specifically to the Z terminal of the second switching circuit 2).

[0217] According to Figure 3(B), one side of the resonant capacitor Cr is connected to the first switching circuit 1 (specifically, to the Z terminal of the first switching circuit 1), and the other side is connected to the second switching circuit 2 (specifically, to the Z terminal of the second switching circuit 2). The resonant inductor Lr is connected between the midpoint of the series connection of the two capacitor units C1 and C2 and the midpoint of the series connection of the two switching circuits 1 and 2.

[0218] As shown in Figures 3(A) and 3(B), the output of the DC / DC power converter 4 may include an optional third output terminal OUT3. According to Figure 3(A), the optional third output terminal OUT3, the midpoint between the two switching circuits 1 and 2, the midpoint between the two capacitor units C1 and C2, and the second input terminal IN2 are interconnected. According to Figure 3(B), the optional third output terminal OUT3, the midpoint between the two capacitor units C1 and C2, and the second input terminal IN2 are interconnected.

[0219] Figures 4(A) and 4(B) respectively illustrate DC / DC power converters according to embodiments of the present invention.

[0220] The DC / DC power converter 4 in Figure 4(A) corresponds to the DC / DC power converter 4 in Figure 3(A), where an embodiment of two switching circuits 1, 2 and two capacitor units C1, C2 is shown. The descriptions of the DC / DC power converters 4 in Figures 2 and 3(A) are correspondingly applicable to the DC / DC power converter 4 in Figure 4(A). Therefore, the following description mainly focuses on the additional features of the DC / DC power converter 4 in Figure 4(A) relative to the DC / DC power converters 4 in Figures 2 and 3(A).

[0221] As shown in Figure 4(A), each switching unit 11, 12 of the first switching circuit 1 and each switching unit 21, 22 of the second switching circuit 2 includes two controllable semiconductor switches. Therefore, the series connection of the first switching circuit 1 and the second switching circuit 2 corresponds to the series connection of eight controllable semiconductor switches 11a, 11b, 12a, 12b, 21a, 21b, 22a, and 22b. As mentioned above, the number of switches in each switching unit can be greater than two. Advantageously, as shown in Figure 4(A), the number of switches in the two switching units 11, 12 of the first switching circuit 1 can be the same. Advantageously, as shown in Figure 4(A), the number of switches in the two switching units 21, 22 of the second switching circuit 2 can be the same. Advantageously, as shown in Figure 4(A), the number of switches in each switching unit 11, 12, 21, 22 of the first and second switching circuits 1 and 2 can be the same.

[0222] According to the embodiment of FIG4(A), the controllable semiconductor switch is an insulated gate bipolar transistor (IGBT). Optionally or additionally, the controllable semiconductor switches of the first switching circuit 1 and the second switching circuit 2 can be at least one different type of transistor. That is, the controllable semiconductor switches of the first switching circuit 1 and the second switching circuit 2 can be one or more IGBTs, one or more bipolar junction transistors (BJTs), and / or one or more field-effect transistors (FETs), for example, one or more metal-oxide-semiconductor field-effect transistors (MOSFETs). Advantageously, as shown in FIG4(A), the controllable semiconductor switches of the first and second switching circuits 1 and 2 have the same transistor type.

[0223] As shown in Figure 4(A), eight IGBTs 11a, 11b, 12a, 12b, 21a, 21b, 22a, and 22b are connected in series as follows: the collector of the topmost IGBT 11a is connected to the first input terminal IN1 and the first output terminal OUT1. The emitter of the bottommost IGBT 22b is connected to the second output terminal OUT2. The other six IGBTs 11b, 12a, 12b, 21a, 21b, and 22a are connected such that the collector of each of these six IGBTs is connected to the emitter of the corresponding preceding IGBT, and the emitter of each of these six IGBTs is connected to the collector of the corresponding following IGBT. For example, the collector of the second topmost IGBT 11b in the series connection is connected to the emitter of the topmost IGBT 11a (i.e., the corresponding preceding IGBT) in the series connection. The emitter terminal of the second topmost IGBT 11b is connected to the collector terminal of the third topmost IGBT 12a (correspondingly the next IGBT) in the series connection of the IGBTs.

[0224] As shown in Figure 4(A), an optional diode can be connected in parallel with each IGBT. Specifically, the optional diode can be connected in parallel with each IGBT such that the anode of the optional diode is connected to the emitter terminal of the corresponding IGBT, and the cathode of the optional diode is connected to the collector terminal of the corresponding IGBT.

[0225] The control signal used to control the IGBT can be provided to the gate terminal of the IGBT. That is, the control signal can be provided to the control terminal of the controllable semiconductor switch.

[0226] When the controllable semiconductor switches 11a, 11b, 12a, 12b, 21a, 21b, 22a, and 22b in the first and second switching circuits 1 and 2 are implemented using different transistor types, the series connection of these controllable semiconductor switches is implemented accordingly. In this case, optional diodes can be connected in anti-parallel to each controllable semiconductor switch.

[0227] Since each switching unit 11, 12 of the first switching circuit 1 and each switching unit 21, 22 of the second switching circuit 2 includes two controllable semiconductor switches, the first switching circuit 1 and the second switching circuit 2 respectively include diode units D11 and D21. Each diode unit includes two diodes. In addition, the first capacitor unit C1 and the second capacitor unit C2 respectively include two capacitors C11, C12 and C21, C22.

[0228] The number of diode units and the number of capacitors in the corresponding diode units of the switching circuit depend on the number of controllable semiconductor switches in each switching unit of the switching circuit. Specifically, the number of diode units in the switching circuit is one less than the number of controllable semiconductor switches in each switching unit of the switching circuit, and the number of capacitors in the corresponding capacitor units is equal to the number of controllable semiconductor switches in each switching unit of the switching circuit. Therefore, as described above, since the number of switches in each switching unit can be greater than two, the number of diode units in the first switching circuit 1 and the second switching circuit 2 can both be greater than one. Furthermore, as described above, since the number of switches in each switching unit can be greater than two, the number of capacitors in the first capacitor unit C1 and the number of capacitors in the second capacitor unit C2 can both be greater than two.

[0229] As shown in Figure 4(A), the midpoint of the series connection of the two capacitors C11 and C12 in the first capacitor unit C1 is connected to the midpoint of the series connection of the two controllable semiconductor switches 11a and 11b in the first switching unit 1 of the first switching circuit 1 via the first diode D11a of the diode unit D11. Furthermore, the midpoint of the series connection of the two capacitors C11 and C12 in the first capacitor unit C1 is connected to the midpoint of the series connection of the two controllable semiconductor switches 12a and 12b in the second switching unit 1 of the first switching circuit 1 via the second diode D11b of the diode unit D11. Specifically, the midpoint of the series connection of the two capacitors C11 and C12 in the first capacitor unit C1 is connected to the anode of the first diode D11a in the diode unit D11, wherein the cathode of the first diode D11a is connected to the midpoint of the series connection of the two switches 11a and 11b in the first switching unit 1 of the first switching circuit 1. The midpoint of the series connection of the two capacitors C11 and C12 in the first capacitor unit C1 is connected to the cathode of the second diode D11b in the diode unit D11, wherein the anode of the second diode D11b is connected to the midpoint of the series connection of the two switches 12a and 12b in the second switch unit 12 of the first switch circuit 1.

[0230] Furthermore, the midpoint of the series connection of the two capacitors C21 and C22 in the second capacitor unit C2 is connected to the midpoint of the series connection of the two controllable semiconductor switches 21a and 21b in the first switching unit 21 of the second switching circuit 2 via the first diode D21a of the diode unit D21. Additionally, the midpoint of the series connection of the two capacitors C21 and C22 in the second capacitor unit C2 is connected to the midpoint of the series connection of the two controllable semiconductor switches 22a and 22b in the second switching unit 22 of the second switching circuit 2 via the second diode D21b of the diode unit D21. Specifically, the midpoint of the series connection of the two capacitors C21 and C22 in the second capacitor unit C2 is connected to the anode of the first diode D21a in the diode unit D21, wherein the cathode of the first diode D21a is connected to the midpoint of the series connection of the two switches 21a and 21b in the first switching unit 21 of the second switching circuit 2. The midpoint of the series connection of the two capacitors C21 and C22 in the second capacitor unit C2 is connected to the cathode of the second diode D21b in the diode unit D21. The anode of the second diode D21b is connected to the midpoint of the series connection of the two switches 22a and 22b in the second switch unit 22 of the second switch circuit 2.

[0231] The dimensions of the two capacitors C11 and C12 in the first capacitor unit C1 are such that the voltage at each capacitor in the first capacitor unit C1 is equal to the voltage Vin at the first capacitor unit C1 divided by the number of capacitors in the first capacitor unit C1. According to the embodiment in Figure 4(A), this number corresponds to two. The same applies to the second capacitor unit C2. That is, the dimensions of the two capacitors C21 and C22 in the second capacitor unit C2 are such that the voltage at each capacitor in the second capacitor unit C2 is equal to the voltage at the second capacitor unit C2 divided by the number of capacitors in the second capacitor unit C2. According to the embodiment in Figure 4(A), this number corresponds to two.

[0232] Furthermore, as shown in Figure 4(A), one side of the series connection between the resonant capacitor Cr and the resonant inductor Lr of the resonant circuit 3 is connected to the midpoint between the two switching units 11 and 12 of the first switching circuit 1, and the other side is connected to the midpoint between the two switching units 21 and 22 of the second switching circuit 2. The midpoint between the two switching units 11 and 12 of the first switching circuit 1 is connected to the Z terminal of the first switching circuit 1. The midpoint between the two switching units 21 and 22 of the second switching circuit 2 is connected to the Z terminal of the second switching circuit 2.

[0233] The DC / DC power converter 4 in Figure 4(B) corresponds to the DC / DC power converter 4 in Figure 4(A). The difference between these two DC / DC power converters 4 lies in the implementation of the resonant circuit 3, which corresponds to the implementation of the resonant circuit 3 in the DC / DC power converter of Figure 3(B). Therefore, the above description of the DC / DC power converter 4 in Figure 4(A) applies accordingly to the DC / DC power converter 4 in Figure 4(B). The following mainly describes the differences between the DC / DC power converter 4 in Figure 4(A) and the DC / DC power converter 4 in Figure 4(B). The description of the implementation of the resonant circuit 3 of the DC / DC power converter 4 in Figure 4(B) refers to the description of the DC / DC power converter 4 in Figure 3(B).

[0234] As shown in Figure 4(B), one side of the resonant capacitor Cr in the resonant circuit 3 is connected to the midpoint between the two switching units 11 and 12 of the first switching circuit 1, and the other side is connected to the midpoint between the two switching units 21 and 22 of the second switching circuit 2. One side of the resonant inductor Lr in the resonant circuit 3 is connected to the midpoint between the two capacitors C1 and C2, and the other side is connected to the midpoint between the two switching circuits 1 and 2.

[0235] Figures 5(A) and 5(B) respectively illustrate DC / DC power converters according to embodiments of the present invention.

[0236] The DC / DC power converter 4 in Figure 5(A) corresponds to the DC / DC power converter 4 in Figure 4(A), except that the implementation of the second switching circuit 2 is different. The descriptions of the DC / DC power converters 4 in Figures 2, 3(A), and 4(A) are correspondingly applicable to the DC / DC power converter 4 in Figure 5(A). Therefore, the following mainly describes the differences between the DC / DC power converter 4 in Figure 5(A) and the DC / DC power converter 4 in Figure 4(A).

[0237] As shown in Figure 5(A), the two switches of each switching unit 21, 22 of the second switching circuit 2 are not controllable semiconductor switches. That is, the two switches of each switching unit 21, 22 of the second switching circuit 2 are two uncontrollable semiconductor switches, specifically two diodes. Therefore, the series connection of the two switching units 21, 22 of the second switching circuit 2 of the DC / DC power converter 4 according to Figure 5(A) corresponds to the series connection of four diodes 21a, 21b, 22a, and 22b. As mentioned above, each switching unit 21, 22 of the second switching circuit 2 may include more than two uncontrollable semiconductor switches, specifically more than two diodes.

[0238] As shown in Figure 5(A), four diodes 21a, 21b, 22a, and 22b are connected in series as follows: the cathode of the topmost diode 21a in the series connection is connected to the midpoint between the two switching circuits 1 and 2. The anode of the bottommost diode 22b in the series connection is connected to the output terminal OUT2. The other two diodes 21b and 22a in the second switching circuit 2 are connected such that the cathode of each of these two diodes is connected to the anode of the corresponding preceding diode, and the anode of each of these two diodes is connected to the cathode of the corresponding following diode. That is, the cathode of the second topmost diode 21b in the series connection is connected to the anode of the topmost diode 21a (the corresponding preceding diode) in the series connection. The anode of the second topmost diode 21b is connected to the cathode of the second bottommost diode 22a (the corresponding following diode) in the series connection. The cathode of the second bottom diode 22a is connected to the anode of the second top diode 21b (corresponding to the front diode), and the anode of the second bottom diode 22a is connected to the cathode of the bottom diode 22b (corresponding to the rear diode) in the series connection of diodes.

[0239] Since the switch of the second switching circuit 2 is an uncontrollable semiconductor switch, the second switching circuit 2 of the DC / DC power converter 4 in Figure 5(A) does not include a diode unit and the second capacitor unit C2 includes only one capacitor C21.

[0240] The DC / DC power converter 4 in Figure 5(B) corresponds to the DC / DC power converter 4 in Figure 5(A). The difference between these two DC / DC power converters 4 lies in the implementation of the resonant circuit 3, which corresponds to the implementation of the resonant circuit 3 in the DC / DC power converters 4 of Figures 3(B) and 4(B). Therefore, the above description of the DC / DC power converter 4 in Figure 5(A) is applicable to the DC / DC power converter 4 in Figure 5(B). The description of the implementation of the resonant circuit 3 in the DC / DC power converter 4 of Figure 5(B) refers to the description of the DC / DC power converter 4 in Figures 3(B) and 4(B).

[0241] Figure 6 Different embodiments of a switching circuit for a DC / DC power converter according to an embodiment of the present invention are shown.

[0242] Figure 6(A) illustrates an embodiment of the first switching circuit 1 of a DC / DC power converter according to an embodiment of the present invention. This embodiment corresponds to the embodiment of the first switching circuit 1 of the DC / DC power converter 4 of FIG. 4(A) and FIG. 4(B). Therefore, the description of the DC / DC power converter 4 of FIG. 4(A) and FIG. 4(B) will be used to further illustrate the present invention. Figure 6 The first switching circuit 1 shown in (A) is described. As shown in Figures 4(A) and 4(B), it can be described according to... Figure 6 The first switching circuit 1 shown in (A) is used to implement the second switching circuit 2 of the DC / DC power converter 4.

[0243] Figure 6 (B) illustrates an embodiment of the second switching circuit 2 of the DC / DC power converter according to an embodiment of the present invention. This embodiment corresponds to the embodiment of the second switching circuit 2 of the DC / DC power converter 4 of FIG. 5(A) and FIG. 5(B). Therefore, the description of the DC / DC power converter 4 of FIG. 5(A) and FIG. 5(B) will be used to further illustrate the present invention. Figure 6 The second switching circuit 1 shown in (B) is described.

[0244] As described above, each switching unit of the corresponding switching circuit (first switching circuit 1 and second switching circuit 2) may include two or more switches. Figure 6 (C) and Figure 6 (D) illustrates cases where each switching unit 11, 12 of the first switching circuit 1 includes two or more controllable semiconductor switches. Therefore, the first switching circuit 1 includes multiple diode units, and the first capacitor unit C1 includes two or more capacitors. The description of the DC / DC converter 4 in Figures 4(A) and 4(B) is accordingly applicable. Figure 6 (C) and Figure 6 (D) First switching circuit 1.

[0245] Figure 6 (C) illustrates a configuration where each switching unit 11, 12 of the first switching circuit 1 comprises three controllable semiconductor switches. Therefore, according to... Figure 6 (C) The first switching circuit 1 includes two diode units D11 and D12, and the first capacitor unit includes three capacitors C11, C12, and C13. Each diode unit includes two diodes. Figure 6 (D) illustrates a first switching circuit 1 where each switching unit 11, 12 comprises four controllable semiconductor switches. Therefore, according to Figure 6 (D) The first switching circuit 1 includes three diode units D11, D12, and D13, and the first capacitor unit includes four capacitors C11, C12, C13, and C14. Each diode unit includes two diodes.

[0246] Figure 6 (C) and Figure 6 The description in (D) applies accordingly to the case where each switching unit 11, 12 of the first switching circuit 1 includes four or more controllable semiconductor switches. In the case where the switches of the second switching circuit 2 are controllable semiconductor switches, Figure 6 (C) and Figure 6 The description of the first switching circuit 1 in (D) applies accordingly to the second switching circuit 2.

[0247] for Figure 6 (C) and Figure 6 The description in (D) assumes that the controllable semiconductor switches 11a, 11b, 11c, 11d, 12a, 12b, 12c, and 12d are IGBTs. This is merely an example and does not limit the present disclosure. As described above, optionally or additionally, the controllable semiconductor switches of the first switching circuit 1 may correspond to one or more other transistor types. Advantageously, the controllable semiconductor switches of the first switching circuit 1 have the same transistor type.

[0248] like Figure 6 As shown in (C), each node between the two capacitors of the first capacitor unit C1 is connected to the first node between the two switches of the first switching unit 11 of the first switching circuit 1 via the first diode of the corresponding diode unit of the two diode units D11 and D12, and is connected to the second node between the two switches of the second switching unit 12 of the first switching circuit 1 via the second diode of the corresponding diode unit. The position of the first node in the series connection of the three switches 11a, 11b, and 11c of the first switching unit 11 corresponds to the position of the second node in the series connection of the three switches 12a, 12b, and 12c of the second switching unit 12. The node between the two capacitors in the series connection of the three capacitors C11, C12, and C13 of the first capacitor unit C1 is connected to different nodes of the two switching units 11 and 12 of the first switching circuit 1.

[0249] like Figure 6 As shown in (C), the positions of each node between the two capacitors in the series connection of the three capacitors C11, C12, and C13 in the first capacitor unit C1, the positions of the corresponding first nodes between the two switches in the series connection of the three switches 11a, 11b, and 11c in the first switch unit 11, and the positions of the corresponding second nodes between the two switches in the series connection of the three switches 12a, 12b, and 12c in the second switch unit 12 correspond to each other.

[0250] Specifically, the node between the topmost capacitor C11 and the second topmost capacitor C12 in the series connection of the capacitors in the first capacitor unit C1 is connected via the first diode D11a of the first diode unit D11 in the two diode units D11 and D12 to the node between the topmost IGBT 11a and the second topmost IGBT 11b in the series connection of the IGBTs in the first switching unit 11 of the first switching circuit 1 (first node). Furthermore, the node between the topmost capacitor C11 and the second topmost capacitor C12 in the first capacitor unit C1 is connected via the second diode D11b of the first diode unit D11 to the node between the topmost IGBT 12a and the second topmost IGBT 12b in the series connection of the IGBTs in the second switching unit 12 of the first switching circuit 1 (second node). The positions of the nodes between the topmost capacitor C11 and the second topmost capacitor C12 in the series connection of the capacitors in the first capacitor unit C1, the positions of the nodes between the topmost IGBT 11a and the second topmost IGBT 11b in the series connection of the IGBTs in the first switching unit 11, and the positions of the nodes between the topmost IGBT 12a and the second topmost IGBT 12b in the series connection of the IGBTs in the second switching unit 12 correspond to each other.

[0251] In addition, such as Figure 6 As shown in (C), the node between the topmost capacitor C12 and the bottommost capacitor C13 in the series connection of the capacitors of the first capacitor unit C1 is connected via the first diode D12a of the second diode unit D12 in the two diode units D11 and D12 to the node between the topmost IGBT 11b and the bottommost IGBT 11c in the series connection of the IGBTs of the first switching unit 11 of the first switching circuit 1 (first node). Furthermore, the node between the topmost capacitor C12 and the bottommost capacitor C13 of the first capacitor unit C1 is connected via the second diode D12b of the second diode unit D12 to the node between the topmost IGBT 12b and the bottommost IGBT 12c in the series connection of the IGBTs of the second switching unit 12 of the first switching circuit 1 (second node). The positions of the nodes between the topmost capacitor C12 and the bottommost capacitor C13 in the series connection of the capacitors in the first capacitor unit C1, the nodes between the topmost IGBT 11b and the bottommost IGBT 11c in the series connection of the IGBTs in the first switching unit 11, and the nodes between the topmost IGBT 12b and the bottommost IGBT 12c in the series connection of the IGBTs in the second switching unit 12 correspond to each other.

[0252] The dimensions of the three capacitors C11, C12, and C13 in capacitor unit C1 are such that the voltage at each capacitor in the first capacitor unit C1 is equal to the voltage at the first capacitor unit C1 divided by the number of capacitors in the first capacitor unit C1.

[0253] Figure 6 The above description of (C) applies accordingly. Figure 6 (D) First switching circuit 1.

[0254] like Figure 6 As shown in (D), each node between the two capacitors of the first capacitor unit C1 is connected to a first node between the two switches of the first switching unit 11 of the first switching circuit 1 via the first diode of the corresponding diode unit among the three diode units D11, D12, and D13, and is connected to a second node between the two switches of the second switching unit of the first switching circuit 1 via the second diode of the corresponding diode unit. The node of the series connection of the four capacitors C11, C12, C13, and C14 of the first capacitor unit C1 is connected to different nodes of the two switching units 11 and 12 of the first switching circuit 1. The positions of the nodes between the two capacitors in the series connection of the four capacitors C11, C12, C13, and C14 of the first capacitor unit C1, the positions of the corresponding first nodes between the two switches in the series connection of the four switches 11a, 11b, 11c, and 11d of the first switching unit 11, and the positions of the corresponding second nodes between the two switches in the series connection of the four switches 12a, 12b, 12c, and 12d of the second switching unit 12 correspond to each other.

[0255] Specifically, the node between the topmost capacitor C11 and the second topmost capacitor C12 in the series connection of the capacitors in the first capacitor unit C1 is connected via the first diode D11a of the first diode unit D11 in the three diode units D11, D12, and D13 to the node between the topmost IGBT 11a and the second topmost IGBT 11b in the series connection of the IGBTs in the first switching unit 11 of the first switching circuit 1 (first node). Furthermore, the node between the topmost capacitor C11 and the second topmost capacitor C12 in the first capacitor unit C1 is connected via the second diode D11b of the first diode unit D11 to the node between the topmost IGBT 12a and the second topmost IGBT in the series connection of the IGBTs in the second switching unit 12 of the first switching circuit 1 (second node). The node between the topmost capacitor C11 and the second topmost capacitor C12 in the series connection of the capacitors in the first capacitor unit C1, the node between the topmost IGBT 11a and the second topmost IGBT 11b in the series connection of the IGBTs in the first switching unit 11, and the node between the topmost IGBT 12a and the second topmost IGBT 12b in the series connection of the IGBTs in the second switching unit 12 correspond to each other.

[0256] Furthermore, such as Figure 6 As shown in (D), the node between the topmost capacitor C12 and the bottommost capacitor C13 in the series connection of the capacitors of the first capacitor unit C1 is connected via the first diode D12a of the second diode unit D12 in the three diode units D11, D12, and D13 to the node between the topmost IGBT 11b and the bottommost IGBT 11c in the series connection of the IGBTs of the first switching unit 11 of the first switching circuit 1 (first node). Furthermore, the node between the topmost capacitor C12 and the bottommost capacitor C13 of the first capacitor unit C1 is connected via the second diode D12b of the second diode unit D12 to the node between the topmost IGBT 12b and the bottommost IGBT 12c in the series connection of the IGBTs of the second switching unit 12 of the first switching circuit 1 (second node). The positions of the nodes between the topmost capacitor C12 and the bottommost capacitor C13 in the series connection of the capacitors in the first capacitor unit C1, the nodes between the topmost IGBT 11b and the bottommost IGBT 11c in the series connection of the IGBTs in the first switching unit 11, and the nodes between the topmost IGBT 12b and the bottommost IGBT 12c in the series connection of the IGBTs in the second switching unit 12 correspond to each other.

[0257] In addition, such as Figure 6 As shown in (D), the node between the second bottommost capacitor C13 and the bottommost capacitor C14 in the series connection of the capacitors of the first capacitor unit C1 is connected via the first diode D13a of the third diode unit D13 in the three diode units D11, D12, and D13 to the node between the second bottommost IGBT 11c and the bottommost IGBT 11d in the series connection of the IGBTs of the first switching unit 11 of the first switching circuit 1 (first node). Furthermore, the node between the second bottommost capacitor C13 and the bottommost capacitor C14 of the first capacitor unit C1 is connected via the second diode D13b of the third diode unit D13 to the node between the second bottommost IGBT 12c and the bottommost IGBT 12d in the series connection of the IGBTs of the second switching unit 12 of the first switching circuit 1 (second node). The positions of the nodes between the second bottom capacitor C13 and the bottom capacitor C14 in the series connection of the capacitors in the first capacitor unit C1, the positions of the nodes between the second bottom IGBT 11c and the bottom IGBT 11d in the series connection of the IGBTs in the first switching unit 11, and the positions of the nodes between the second bottom IGBT 12c and the bottom IGBT 12d in the series connection of the IGBTs in the second switching unit 12 correspond to each other.

[0258] The dimensions of the four capacitors C11, C12, C13, and C14 in capacitor unit C1 are such that the voltage at each capacitor in the first capacitor unit C1 is equal to the voltage at the first capacitor unit C1 divided by the number of capacitors in the first capacitor unit C1.

[0259] Figure 7 The illustration shows different states of the DC / DC power converter according to embodiments of the invention, particularly two steady-state and two transient switching states (also known as transient switching states), when the DC / DC power converter switches between two steady states according to embodiments of the invention.

[0260] Figure 7 (A) to Figure 7 The DC / DC power converter 4 of (J) corresponds to the DC / DC power converter 4 of Figure 5(A). The above description of the DC / DC power converter 4 of Figure 5(A) applies accordingly. Figure 7 (A) to Figure 7 (J) DC / DC power converter 4. Figure 7The controllable semiconductor switches 11a, 11b, 12a, and 12b of the first switching circuit 1 of the DC / DC power converter 4 are IGBTs. This is merely an example and does not limit the present disclosure. That is, as described above, the switching of the first switching circuit 1 can be implemented by different transistor types.

[0261] The following combination Figure 7 (A) to Figure 7 (J), for controlling the operation of DC / DC power converter 4 Figure 7 The switching control of IGBTs 11a, 11b, 12a, and 12b in the first switching circuit 1 of the DC / DC power converter 4 shown is described below:

[0262] This control can be performed by a control unit, such as the control unit shown in Figure 2(B). The control unit can be part of the DC / DC power converter 4 or an external control unit.

[0263] The two switching units 11 and 12 of the first switching circuit 1 complementarily switch between an on state and an off state. Optionally, these switching units complementarily switch with a 50% duty cycle.

[0264] The switching unit is in a conducting state when all switches in the switching unit are in the ON state. Conversely, the switching unit is in a non-conducting state when all switches in the switching unit are in the OFF state. The switching unit is in a steady state when it is in either the ON or OFF state. The ON state can also be called the on state or the closed state. The OFF state can also be called the off state or the closed state.

[0265] The switching of IGBTs 11a, 11b, 12a, and 12b in the first switching circuit 1 causes a change in the voltage across the uncontrolled semiconductor switches 21a, 21b, 22a, and 22b (which are diodes) in the second switching circuit 2. Therefore, due to the switching of IGBTs 11a, 11b, 12a, and 12b in the first switching circuit 1, the switching units 21 and 22 of the second switching circuit 2 also switch complementaryly. Specifically, the first switching unit 21 of the second switching circuit 2 switches according to the first switching unit 11 of the first switching circuit 1, and the second switching unit 22 of the second switching circuit 2 switches according to the second switching unit 12 of the first switching circuit 1. That is, when the first switching unit 11 of the first switching circuit 1 is in the on state, the first switching unit 21 of the second switching circuit 2 is also in the on state, while the two second switching units 12 and 22 are in the off state, and vice versa. This also applies to the second switching units 12 and 22 of the DC / DC power converter 4.

[0266] Therefore, due to the controlled switching of switches 11a, 11b, 12a, and 12b in the first switching circuit 1, the first switching units 11 and 21 switch together between the on and off states, and the switching of the second switching units 12 and 22 complements that of the first switching units 11 and 21, switching together between the off and on states.

[0267] Figure 7 (A) shows the first steady state of the DC / DC power converter 4, wherein the first switching unit 11 of the first switching circuit 1 and the first switching unit 21 of the second switching circuit 2 are in the on state, while the second switching unit 12 of the first switching circuit 1 and the second switching unit 22 of the second switching circuit 2 are in the off state. Figure 7 (F) illustrates the second steady state of the DC / DC power converter 4, wherein the second switching unit 12 of the first switching circuit 1 and the second switching unit 22 of the second switching circuit 2 are in a conducting state, while the first switching unit 11 of the first switching circuit 1 and the first switching unit 21 of the second switching circuit 2 are in a non-conducting state. In the first steady state of the DC / DC power converter 4, resonance occurs between the first capacitor unit C1 and the resonant circuit. In the second steady state of the DC / DC power converter 4, resonance occurs between the second capacitor unit C2 and the resonant circuit.

[0268] exist Figure 7 (A) to Figure 7 In (J), the conducting components of the DC / DC power converter are highlighted in bold. Specifically, the bold, undotted portions of the DC / DC power converter represent the active current paths through which current flows during operation of the DC / DC power converter. The IGBTs, indicated by dashed lines, are in the conducting state.

[0269] Figure 7 (B) to Figure 7 (E) illustrates the switching of the controllable semiconductor switch controlling the first switching circuit 1, causing the DC / DC power converter 4 to switch from... Figure 7 The first steady state transition shown in (A) is now... Figure 7 (F) shows the transient switching state of DC / DC power converter 4 in the second steady state. Figure 7 (G) to Figure 7 (J) illustrates the switching of the controllable semiconductor switch controlling the first switching circuit 1, causing the DC / DC power converter 4 to switch from... Figure 7 The second steady-state transition shown in (F) is... Figure 7 (A) shows the transient switching state of DC / DC power converter 4 during the first steady state.

[0270] like Figure 7As shown in (A), in the first steady state, the IGBTs 11a and 11b of the first switching unit 11 of the first switching circuit 1 are in the on state, and the diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2 are in the on state (forward biased). The IGBTs 12a and 12b of the second switching unit 12 of the first switching circuit 1 are in the off state, and the diodes 22a and 22b of the second switching unit 22 of the second switching circuit 2 are in the off state (reverse biased). Therefore, current flows through the two capacitors C11 and C12 of the first capacitor unit C1, the two IGBTs 11a and 11b of the first switching unit 11 of the first switching circuit 1, the resonant capacitor Cr and the resonant inductor Lr of the resonant circuit 3, and the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2. In the first steady state, the first capacitor unit C1 discharges.

[0271] like Figure 7 As shown in (F), in the second steady state, the IGBTs 11a and 11b of the first switching unit 11 of the first switching circuit 1 are in a non-conducting state, and the diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2 are in a non-conducting state (reverse biased). The IGBTs 12a and 12b of the second switching unit 12 of the first switching circuit 1 are in a conducting state, and the diodes 22a and 22b of the second switching unit 22 of the second switching circuit 2 are in a conducting state (forward biased). Therefore, current flows through the resonant capacitor Cr and resonant inductor Lr of the resonant circuit 3, the two IGBTs 12a and 12b of the second switching unit 12 of the first switching circuit 1, the capacitor C21 of the second capacitor unit C2, and the two diodes 22a and 22b of the second switching unit 22 of the second switching circuit 2. In the second steady state, the second capacitor unit C2 is charged.

[0272] The following describes the process of converting DC / DC power converter 4 from its first steady state ( Figure 7 (A) shows) switching to the second stable state ( Figure 7 The control of IGBTs 11a, 11b, 12a, and 12b in the first switching circuit shown in (F) is described below:

[0273] like Figure 7As shown in (B), firstly, the IGBT 11a of the first switching unit 11 of the first switching circuit 1 is turned off to a non-conducting state (switching close to zero current). Therefore, current flows through the capacitor C12 of the first capacitor unit C1, the first diode D11a of the diode unit D11, the second topmost IGBT 11b in the series connection of the IGBTs of the first switching circuit 1, the resonant circuit, and the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2. Figure 7 (B) The status of DC / DC power converter 4 and Figure 7 The difference shown in (A) regarding the previous state is that, Figure 7 (A) Under steady-state conditions, IGBT 11a is in the on state, while Figure 7 (B) In the transient switching state, IGBT 11a is switched to the non-conducting state.

[0274] Next, as Figure 7 As shown in (C), the IGBT 12a of the second switching unit 12 of the first switching circuit 1 is turned on (zero current switching). However, current continues to flow through the capacitor C12 of the first capacitor unit C1, the first diode D11a of the diode unit D11, the second topmost IGBT 11b in the series connection of the IGBTs of the first switching circuit 1, the resonant circuit, and the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2. Figure 7 (C) The status of DC / DC power converter 4 and Figure 7 The difference shown in (B) regarding the previous state is that, Figure 7 In the transient switching state of (B), IGBT 12a is in a non-conducting state, while... Figure 7 In the transient switching state of (C), IGBT12a is switched to the on state.

[0275] Next, as Figure 7 As shown in (D), the IGBT 11b of the first switching unit 11 of the first switching circuit 1 is turned off to a non-conducting state (near-zero current switching). Therefore, current flows through the resonant circuit, the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2, the diode connected in parallel with the bottommost IGBT 12b (IGBT 12b is in a non-conducting state) in the series connection with the IGBT, and the diode connected in parallel with the second bottommost IGBT 12a (IGBT 12a is in a conducting state) in the series connection with the IGBT. Figure 7 (D) The state of DC / DC power converter 4 and Figure 7 The difference shown in (C) regarding the previous state is that, Figure 7 In the transient switching state of (C), IGBT 11b is in the on state, while... Figure 7 In the transient switching state of (D), IGBT 11b is switched to the non-conducting state.

[0276] Next, as Figure 7 As shown in (E), the IGBT 12b of the second switching unit 12 of the first switching circuit 1 is turned on (zero current switching). However, current continues to flow through the resonant circuit, the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2, the diode connected in parallel with the bottommost IGBT 12b (IGBT 12b is in the on state) in the series connection with the IGBT, and the diode connected in parallel with the second bottommost IGBT 12a (IGBT 12a is in the on state) in the series connection with the IGBT. Figure 7 (E) DC / DC power converter 4 status and Figure 7 The difference shown in (D) regarding the previous state is that, Figure 7 In the transient switching state of (D), IGBT 12b is in a non-conducting state, while... Figure 7 During the transient switching state of (E), IGBT 12b is switched to the on state.

[0277] Next, as Figure 7 As shown in (F), once the current direction changes: the diodes connected in parallel with IGBT 12a and IGBT 12b are reverse biased; the diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2 are reverse biased and in a non-conducting state; and the diodes 22a and 22b of the second switching unit 22 of the second switching circuit 2 are forward biased and in a conducting state. Therefore, current flows through the resonant circuit, the two IGBTs 12a and 12b of the second switching unit 12 of the first switching circuit 1, the capacitor C21 of the second capacitor unit C2, and the two diodes 22a and 22b of the second switching unit 22 of the second switching circuit 2. The second capacitor unit C2 is charged. This state corresponds to the second steady state of the DC / DC power converter 4. Figure 7 (E) transient switching state and Figure 7 The steady states of (F) can transition instantaneously (transition time = 0 ns).

[0278] In summary, the first switching unit 11 of the first switching circuit 1 is switched from the on state to the following state ( Figure 7 (A) Switch to non-conducting state ( Figure 7 (D) Figure 7 (E), and Figure 7(F)): Based on the position of IGBTs 11a and 11b in the series connection of the first switching unit 11, the two IGBTs 11a and 11b of the first switching unit 11 are switched from the on state to the off state in sequence, so that the IGBT 11a of the first switching unit 11 that is farthest from the midpoint of the series connection of the two switching units 11 and 12 of the first switching circuit 1 is switched from the on state to the off state first.

[0279] The second switching unit 12 of the first switching circuit 1 is switched from the non-conducting state as follows ( Figure 7 (A) Switch to the on state ( Figure 7 (E) and Figure 7 (F)): Based on the position of IGBTs 12a and 12b of the second switching unit 12 in the series connection, the two IGBTs 12a and 12b of the second switching unit 12 are switched from the non-conducting state to the conducting state in sequence, so that the switch 12a of the second switching unit 12 connected to the midpoint of the series connection of the two switching units 11 and 12 of the first switching circuit 1 is switched from the non-conducting state to the conducting state first.

[0280] In summary, the first switching unit 11 of the first switching circuit 1 is switched from the on state to the off state, and the second switching unit 12 of the first switching circuit 1 is switched from the off state to the on state as follows: The IGBTs 11a and 11b of the first switching unit 11 and the IGBTs 12a and 12b of the second switching unit 12 are alternately switched, such that…

[0281] First, the switch of the first switching unit 11 (i.e., IGBT 11a) switches from the on state to the off state, and then the switch of the second switching unit 12 (i.e., IGBT 12a) switches from the off state to the on state.

[0282] - The switches 11a and 11b of the first switching unit 11 are switched sequentially from the on state to the off state, and

[0283] - The switches 12a and 12b of the second switching unit 12 are switched from the non-conducting state to the conducting state in sequence.

[0284] The following describes the process of converting DC / DC power converter 4 from the second steady state ( Figure 7 (F) shows) switching to the first stable state ( Figure 7 The control of IGBTs 11a, 11b, 12a, and 12b in the first switching circuit shown in (A) is described below:

[0285] like Figure 7As shown in (G), firstly, the IGBT 12b of the second switching unit 12 of the first switching circuit 1 is turned off to a non-conducting state. Therefore, current flows through the resonant circuit, IGBT 12a, the second diode D11b of diode unit D11, capacitor C12 of the first capacitor unit C1, capacitor C21 of the second capacitor unit C2, and the two diodes 22a and 22b of the second switching unit 22 of the second switching circuit 2. Figure 7 The status of (G) DC / DC power converter 4 and Figure 7 The difference shown in (F) regarding the previous state is that, Figure 7 Under steady-state conditions (F), IGBT 12b is in the on state, while... Figure 7 During the transient switching state of (G), IGBT 12b is switched to the non-conducting state.

[0286] Next, as Figure 7 As shown in (H), the IGBT 11b of the first switching unit 11 of the first switching circuit 1 is turned on to the conducting state (zero current switching). However, the current continues to flow through the resonant circuit, IGBT 12a, the second diode D11b of diode unit D11, capacitor C12 of the first capacitor unit C1, capacitor C21 of the second capacitor unit C2, and the two diodes 22a and 22b of the second switching unit 22 of the second switching circuit 2. Figure 7 The state of (H) DC / DC power converter 4 and Figure 7 The difference shown in (G) regarding the previous state is that, Figure 7 During the transient switching state of (G), IGBT 11b is in a non-conducting state, while... Figure 7 During the transient switching state of (H), IGBT 11b is switched to the on state.

[0287] Next, as Figure 7 As shown in (I), the IGBT 12a of the second switching unit 12 of the first switching circuit 1 is turned off to a non-conducting state (zero-current switching). Because in Figure 7 (H) transient switching state and Figure 7 The current direction changes between the transient switching states of (I), therefore... Figure 7 (I) The current flow in the transient switching state is as follows: the current flows through the resonant circuit, the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2, the capacitor C12 of the first capacitor unit C1, the first diode D11a of the diode unit D11, and the IGBT 11b. Figure 7 (I) The status of DC / DC power converter 4 and Figure 7 The difference shown in (H) in the previous state is that, Figure 7In the transient switching state of (H), IGBT 12a is in the on state, while... Figure 7 In the transient switching state of (I), IGBT 12a is switched to the non-conducting state.

[0288] Next, as Figure 7 As shown in (J), the IGBT 11a of the first switching unit 11 of the first switching circuit 1 is turned on to the conducting state (near-zero current switching). Therefore, current flows through the two capacitors C11 and C12 of the first capacitor unit C1, the two IGBTs 11a and 11b of the first switching unit 11 of the first switching circuit 1, the resonant circuit, and the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2. Figure 7 (J) DC / DC power converter 4 status and Figure 7 The difference shown in (I) regarding the previous state is that, Figure 7 In the transient switching state of (I), IGBT 11a is in a non-conducting state, while... Figure 7 During the transient switching state of (J), IGBT 11a is switched to the on state.

[0289] Next, as Figure 7 As shown in (A), in the first steady state, current flows through the two capacitors C11 and C12 of the first capacitor unit C1, the two IGBTs 11a and 11b of the first switching unit 11 of the first switching circuit 1, the resonant circuit, and the two diodes 21a and 21b of the first switching unit 21 of the second switching circuit 2. The first capacitor unit C1 discharges. Figure 7 (J) transient switching state and Figure 7 (A) can transition instantaneously between its first steady states (transition time = 0 ns).

[0290] In summary, the first switching unit 11 of the first switching circuit 1 is switched from the non-conducting state as follows: Figure 7 (F)) Switch to the on state ( Figure 7 (J) and Figure 7 (A)): Based on the position of the IGBTs 11a and 11b of the first switching unit 11 in the series connection, the two IGBTs 11a and 11b of the first switching unit 11 are switched from the non-conducting state to the conducting state in sequence, so that the switch 11b of the first switching unit 11, which is connected to the midpoint of the series connection of the two switching units 11 and 12 of the first switching circuit 1, is switched from the non-conducting state to the conducting state first.

[0291] The second switching unit 12 of the first switching circuit 1 is switched from the on state as follows ( Figure 7 (F) Switch to non-conducting state ( Figure 7 (I) Figure 7(J), and Figure 7 (A)): Based on the position of IGBTs 12a and 12b in the series connection of the second switching unit 12, the two IGBTs 12a and 12b of the second switching unit 12 are switched from the on state to the off state in sequence, so that the IGBT 12b of the second switching unit 12 that is farthest from the midpoint of the series connection of the two switching units 11 and 12 of the first switching circuit 1 is switched from the on state to the off state first.

[0292] In summary, the first switching unit 11 of the first switching circuit 1 is switched from a non-conducting state to a conducting state, and the second switching unit 12 of the first switching circuit 1 is switched from a conducting state to a non-conducting state as follows: The IGBTs 11a and 11b of the first switching unit 11 and the IGBTs 12a and 12b of the second switching unit 12 are alternately switched, such that…

[0293] First, the switch of the second switching unit 12 (i.e., IGBT 12b) switches from the on state to the off state, and then the switch of the first switching unit 11 (i.e., IGBT 11b) switches from the off state to the on state.

[0294] - The switches 12a and 12b of the second switching unit 12 are switched sequentially from the on state to the off state, and

[0295] - The switches 11a and 11b of the first switching unit 11 are switched from the non-conducting state to the conducting state in sequence.

[0296] like Figure 7 (A) to Figure 7 As shown in (J), by sequentially switching the switches of each switching unit, the corresponding switching unit of the first switching circuit 1 is switched between the on and off states. By alternately switching the switches of the two switching units 11 and 12 of the first switching circuit 1, the two switching units 11 and 12 of the first switching circuit 1 are complementaryly switched between the on and off states.

[0297] The transient switching state of the DC / DC power converter 4 can occur under low load current or no load current. Therefore, Figure 7 The capacitors C11 and C12 of the first capacitor unit C1 of the DC / DC power converter do not require active balancing and can be naturally maintained at half the voltage of the first capacitor unit C1.

[0298] like Figure 7 As shown, the switches 21a, 21b, 22a, and 22b in the second switching circuit 2 are not uncontrollable semiconductor switches (diodes) but rather controllable semiconductor switches such as IGBTs (not shown in the diagram). Figure 7As shown in the diagram, as described above, the switches 21a, 21b, 22a, and 22b of the second switching circuit 2 are switched according to the switches 11a, 11b, 12a, and 12b of the controllable semiconductors of the first switching circuit 1. That is, the corresponding controllable semiconductor switches of the first switching circuit 1 and the second switching circuit 2 are switched together. Specifically, the topmost switch 21a in the series connection of the switches of the second switching circuit 2 and the topmost switch 11a in the series connection of the switches of the first switching circuit 1 are switched together, the second topmost switch 21b in the series connection of the switches of the second switching circuit 2 and the second topmost switch 11b in the series connection of the switches of the first switching circuit 1 are switched together, and so on.

[0299] The switching units 11 and 12 of the first switching circuit 1 can switch between the conducting and non-conducting states at a switching frequency less than or equal to the resonant frequency of the resonant circuit. The DC / DC power converter 4 can switch between the conducting and non-conducting states at a switching frequency less than or equal to the resonant frequency of the resonant circuit of the DC / DC power converter 4 in the first steady state. Figure 7 (A) shown) and the second steady state ( Figure 7 Switch between (F) shown.

[0300] The above description applies accordingly when each switching unit of the first switching circuit 1 and optionally the second switching circuit 2 comprises three or more controllable semiconductor switches connected in series.

[0301] For example, the switching time of the controllable semiconductor switch used to switch between the first switching circuit 1 and optionally the second switching circuit 2 can correspond to tens of microseconds. Figure 7 (B) and Figure 7 (C) The delay time between transient state transitions, Figure 7 (C) and Figure 7 The delay between the transient state transitions in (D), and Figure 7 The delay between the transient switching states of (D) and 7(E) can be, for example, 100 ns. Figure 7 (G) and Figure 7 The delay between the transient switching states of (H) and Figure 7 (I) and Figure 7 The delay time between the transient switching states of (J) can be, for example, 100 ns. These delay times depend on the turn-on (on) delay and turn-off (off) delay of the transistor type (e.g., IGBT, BJT, FET, or MOSFET) used to implement the controllable semiconductor switch of the first switching circuit 1 and optionally the second switching circuit 2.

[0302] Figures 8(A) and 8(B) respectively illustrate the arrangement of the DC / DC power converter according to an embodiment of the present invention.

[0303] The above description of the DC / DC power converter arrangement of the third aspect or any embodiment thereof applies accordingly to the DC / DC power converter arrangement 6 of FIG8(A) and FIG8(B).

[0304] The DC / DC power converter arrangement 6 in FIG8(A) includes two DC / DC power converters 41 and 42. The above description of the DC / DC power converter of the first aspect or any embodiment thereof applies accordingly to the DC / DC power converters 41 and 42 of the DC / DC power converter arrangement in FIG8(A). The two DC / DC power converters 41 and 42 may correspond to the DC / DC power converter 4 of FIG2, FIG3(A), FIG4(A), and FIG5(A). That is, the two DC / DC power converters 41 and 42 may be implemented as described above with respect to FIG2, FIG3(A), FIG4(A), and FIG5(A). The two DC / DC power converters 41 and 42 may be implemented identically.

[0305] As shown in Figure 8(A), the DC / DC power converter arrangement 6 includes a cascade of two DC / DC power converters 41 and 42. The output of the first DC / DC power converter 41 of the two DC / DC power converters 41 and 42 is electrically connected to the input of the second DC / DC power converter 42 of the two DC / DC power converters 41 and 42, such that the first capacitor unit C12 of the second DC / DC power converter 42 is connected in parallel to the second capacitor unit C21 of the two capacitor units C11 and C21 of the first DC / DC power converter 41. According to Figure 8(A), the parallel connection of the first capacitor unit C12 of the second DC / DC power converter 42 and the second capacitor unit C21 of the first DC / DC power converter 41 is achieved by a single capacitor unit. This is merely an example and does not limit the present disclosure.

[0306] Specifically, as shown in Figure 8(A), the optional third output terminal OUT31 of the first DC / DC power converter 41 is interconnected with the first input terminal IN12 of the second DC / DC power converter 42. The second output terminal OUT21 of the first DC / DC power converter 41 is interconnected with the second input terminal IN22 of the second DC / DC power converter 42.

[0307] The inputs of the DC / DC power converter arrangement 6 in Figure 8(A) correspond to the inputs of the first DC / DC power converter arrangement 41. Specifically, the first input terminal IN1 of the DC / DC power converter arrangement 6 corresponds to the first input terminal IN11 of the first DC / DC power converter 41, and the second input terminal IN2 of the DC / DC power converter arrangement 6 corresponds to the second input terminal IN21 of the first DC / DC power converter 41. The outputs of the DC / DC power converter arrangement 6 include two output terminals OUT1 and OUT2. The first output terminal OUT1 of the DC / DC power converter arrangement 6 corresponds to the first output terminal OUT11 of the first DC / DC power converter 41, and the second output terminal OUT2 of the DC / DC power converter arrangement 6 corresponds to the second output terminal OUT22 of the second DC / DC power converter 42.

[0308] The DC / DC power converter arrangement 6 of Figure 8(A) may include a control unit (not shown in Figure 8) for controlling the DC / DC power converters of the DC / DC power converter arrangement 6. In particular, the control unit may be used to perform the method according to the second aspect or any embodiment thereof to control the DC / DC power converters.

[0309] The control unit of DC / DC power converter arrangement 6 may include or correspond to a microcontroller, controller, microprocessor, processor, field-programmable gate array (FPGA), application-specific integrated circuit (ASIC), or any combination of the above components.

[0310] The control unit may correspond to the control unit of one of the DC / DC power converters in the DC / DC power converter arrangement 6.

[0311] In the case where two or more DC / DC power converters in the DC / DC power converter arrangement 6 include control units for controlling the respective DC / DC power converters, the control units of the two or more DC / DC power converters can be used to communicate with each other.

[0312] The DC / DC power converter arrangement 6 in Figure 8(B) corresponds to the DC / DC power converter arrangement 6 in Figure 8(A). The difference between these two DC / DC power converter arrangements lies in the implementation of the resonant circuit 3 of the two DC / DC power converters 41 and 42. That is, as shown in Figure 8(A), the resonant capacitor Cr1 and resonant inductor Lr1 of the first DC / DC power converter 41 and the resonant capacitor Cr2 and resonant inductor Lr2 of the second DC / DC power converter 42 are implemented according to the embodiments in Figures 3(A), 4(A), and 5(A). Therefore, the description of this embodiment refers to the description in Figures 3(A), 4(A), and 5(A). As shown in Figure 8(B), the resonant capacitor Cr1 and resonant inductor Lr1 of the first DC / DC power converter 41 and the resonant capacitor Cr2 and resonant inductor Lr2 of the second DC / DC power converter 42 are implemented according to the embodiments in Figures 3(B), 4(B), and 5(B). Therefore, the description of this embodiment is based on the descriptions in FIG3(B), FIG4(B), and FIG5(B).

[0313] The description of the DC / DC power converter arrangement 6 in Figure 8(A) applies accordingly to the DC / DC power converter arrangement 6 in Figure 8(B).

[0314] Figures 9(A) and 9(B) respectively illustrate the arrangement of the DC / DC power converter according to an embodiment of the present invention.

[0315] The DC / DC power converter arrangement 6 in Figure 9(A) corresponds to the DC / DC power converter 6 in Figure 8(A), wherein the DC / DC power converter arrangement 6 in Figure 9(A) includes an additional third DC / DC power converter 6. The description of the DC / DC power converter arrangement 6 in Figure 8(A) applies accordingly to the DC / DC power converter arrangement in Figure 8(A). Therefore, the following description mainly focuses on the additional features of Figure 9(A).

[0316] As shown in Figure 9(A), the DC / DC power converter arrangement 6 includes a cascade of three DC / DC power converters 41, 42, and 43. The connection of the first DC / DC power converter 41 and the second power converter 42 is as described with respect to Figure 8(A).

[0317] The output of the second DC / DC power converter 42 of the three DC / DC power converters 41, 42, and 43 is electrically connected to the input of the third DC / DC power converter 43 of the three DC / DC power converters 41, 42, and 43, such that the first capacitor unit C13 of the third DC / DC power converter 43 is connected in parallel to the second capacitor unit C22 of the two capacitor units C12 and C22 of the second DC / DC power converter 42. According to Figure 9(A), the parallel connection of the first capacitor unit C13 of the third DC / DC power converter 43 and the second capacitor unit C22 of the second DC / DC power converter 42 is achieved by a single capacitor unit. This is merely an example and does not limit the scope of this disclosure.

[0318] Specifically, as shown in Figure 9(A), the optional third output terminal OUT32 of the second DC / DC power converter 42 is interconnected with the first input terminal IN13 of the third DC / DC power converter 43. The second output terminal OUT22 of the second DC / DC power converter 42 is interconnected with the second input terminal IN23 of the third DC / DC power converter 43.

[0319] The input of the DC / DC power converter arrangement 6 in Figure 9(A) corresponds to the input of the first DC / DC power converter arrangement 41. The output of the DC / DC power converter arrangement 6 includes two output terminals OUT1 and OUT2. The first output terminal OUT1 of the DC / DC power converter arrangement 6 corresponds to the first output terminal OUT11 of the first DC / DC power converter 41, and the second output terminal OUT2 of the DC / DC power converter arrangement 6 corresponds to the second output terminal OUT23 of the third DC / DC power converter 43.

[0320] The DC / DC power converter arrangement 6 in Figure 9(B) corresponds to the DC / DC power converter arrangement 6 in Figure 9(A). The difference between these two DC / DC power converter arrangements lies in the implementation of the resonant circuit 3 of the three DC / DC power converters 41, 42, and 43. That is, as shown in Figure 9(A), the resonant capacitor Cr1 and resonant inductor Lr1 of the first DC / DC power converter 41, the resonant capacitor Cr2 and resonant inductor Lr2 of the second DC / DC power converter 42, and the resonant capacitor Cr3 and resonant inductor Lr3 of the third DC / DC power converter 43 are implemented according to the embodiments in Figures 3(A), 4(A), and 5(A). Therefore, the description of this embodiment refers to the description in Figures 3(A), 4(A), and 5(A). As shown in FIG9(B), the resonant capacitor Cr1 and resonant inductor Lr1 of the first DC / DC power converter 41, the resonant capacitor Cr2 and resonant inductor Lr2 of the second DC / DC power converter 42, and the resonant capacitor Cr3 and resonant inductor Lr3 of the third DC / DC power converter 43 are implemented according to the embodiments of FIG3(B), FIG4(B), and FIG5(B). Therefore, the description of this embodiment refers to the description of FIG3(B), FIG4(B), and FIG5(B).

[0321] The description of the DC / DC power converter arrangement 6 in Figure 9(A) applies accordingly to the DC / DC power converter arrangement 6 in Figure 9(B).

[0322] According to this disclosure, the DC / DC power converter arrangement 6 may include three or more cascaded DC / DC power converters. The above description with respect to Figures 8(A), 8(B), 9(A), and 9(B) applies accordingly to this case.

[0323] The DC / DC power converter arrangement 6 of Figures 8(A) and 8(B) can be used to convert the input voltage at its input to the output voltage at its output, which is a multiple of the input voltage and greater than the output voltage that a single DC / DC power converter (e.g., one of the DC / DC power converters of Figures 2, 3, 4, and 5) can provide at its output. The DC / DC power converter arrangement 6 of Figures 9(A) and 9(B) can be used to convert the input voltage at its input to the output voltage at its output, which is a multiple of the input voltage and greater than the output voltage that the DC / DC power converter arrangement 6 of Figures 8(A) and 8(B) can provide at its output. According to an embodiment, the DC / DC power converter arrangement 6 of Figures 8(A) and 8(B) can convert the input voltage at its input to the output voltage at its output, which is three times the input voltage. According to an embodiment, the DC / DC power converter arrangement 6 of Figures 9(A) and 9(B) can convert the input voltage at its input to the output voltage at its output, which is four times the input voltage.

[0324] In the case where the DC / DC power converter arrangement 6 includes three or more cascaded DC / DC power converters, the arrangement can be used to convert the input voltage at its input to the output voltage at its output, which is an integer multiple of the input voltage. This integer multiple is one more than the number of DC / DC power converters in the arrangement 6.

[0325] Figure 10 A system according to an embodiment of the present invention is shown.

[0326] The above description of the system in the fourth aspect or any of its embodiments is accordingly applicable to... Figure 10 The system.

[0327] according to Figure 10 System 9 includes a DC / DC power converter 4 according to the first aspect or any embodiment thereof. Optionally, system 9 includes a DC / DC power converter arrangement 6 according to the third aspect or any embodiment thereof. System 9 also includes a power supply 7 connected to the inputs of the DC / DC power converter 4 and the DC / DC power converter arrangement 6 (particularly to the two input terminals IN1 and IN2 of the input). This power supply is used to provide a DC input voltage Vin to the DC / DC power converter 4 and the DC / DC power converter arrangement 6. For example, the DC input voltage Vin may be between 800V and 1500V. In this case, the switches of the DC / DC power converter 4 and the DC / DC power converter arrangement 6 can be implemented, for example, by 950V or 1200V voltage blocking devices. These devices have lower cost and losses.

[0328] The DC / DC power converter 4 is used to convert a DC input voltage Vin into a DC output voltage Vout, where the DC output voltage Vout is a multiple of the DC input voltage Vin. Specifically, the DC output voltage Vout can be twice the DC input voltage Vin.

[0329] DC / DC power converter arrangement 6 is used to convert a DC input voltage Vin into a DC output voltage Vout, wherein the DC output voltage Vout is a multiple of the DC input voltage Vin. Specifically, the DC output voltage Vout is a multiple of the DC input voltage Vin and can be twice the DC input voltage Vin. According to an embodiment, the DC output voltage Vout (converted by DC / DC power converter arrangement 6) can be an integer multiple of the DC input voltage, wherein this integer multiple is one more than the number of DC / DC power converters in DC / DC power converter arrangement 6.

[0330] The power source 7 may include or correspond to one or more of the following elements: a front DC / DC power converter arrangement, an AC / DC power converter, a battery (optionally rechargeable), a solar photovoltaic (PV) system with one or more solar PV panels, one or more solar PV strings, and a wind power system.

[0331] The arrangement of the DC / DC power converter can correspond to the DC / DC power converter according to the first aspect or any embodiment thereof, or to the DC / DC power converter arrangement according to the third aspect or any embodiment thereof.

[0332] The DC / DC power converter 4 of system 9 can correspond to the DC / DC power converter 4 in Figures 2, 3(A), 3(B), 4(A), 4(B), 5(A), and 5(B). That is, the DC / DC power converter 4 of system 9 can be as described above regarding Figures 2, 3(A), 3(B), 4(A), 4(B), 5(A), and 5(B). Figure 6 ,as well as Figure 7 To implement as described.

[0333] The DC / DC power converter arrangement 6 of system 9 can correspond to the DC / DC power converter arrangement 6 of Figures 8(A), 8(B), 9(A), and 9(B). That is, the DC / DC power converter arrangement 6 of system 9 can be implemented as described above with respect to Figures 8(A), 8(B), 9(A), and 9(B).

[0334] Optionally, system 9 may also include circuit 8 connected to the outputs of DC / DC power converter 4 and DC / DC power converter arrangement 6. Specifically, circuit 8 is connected to two output terminals OUT1 and OUT2 of the outputs of DC / DC power converter 4 and DC / DC power converter arrangement 6. Optionally, circuit 8 is also connected to an optional third output terminal OUT3 of the outputs of DC / DC power converter 4 and DC / DC power converter arrangement 6.

[0335] DC / DC power converter 4 is used to provide DC output voltage Vout to circuit 8. DC / DC power converter arrangement 6 is used to provide DC output voltage Vout to circuit 8.

[0336] Circuit 8 may include or correspond to one or more of the following elements: a DC / DC power converter arrangement, a DC / AC power converter, a DC transmission system, a solid-state transformer, and an electrical load. The DC / DC power converter arrangement may correspond to a DC / DC power converter according to the first aspect or any embodiment thereof, or to a DC / DC power converter arrangement according to the third aspect or any embodiment thereof.

[0337] The DC / DC power converter disclosed herein is based on low voltage and is therefore a low-cost semiconductor device. Consequently, the DC / DC power converter according to this disclosure can be manufactured at low cost and includes low conduction losses. Since the DC / DC power converter disclosed herein is based on the principle of a resonant balancer (i.e., it includes a resonant circuit), the DC / DC power converter has minimal switching losses and thus high efficiency. Furthermore, with the controllable semiconductor switch of the DC / DC power converter switching at a constant 50% duty cycle, a complex controller is not required, and a simple gate driver is sufficient, thereby reducing cost (low cost).

Claims

1. A DC / DC power converter (4) for converting an input voltage (Vin) at the inputs (IN1, IN2) of the DC / DC power converter (4) into an output voltage (Vout) at the outputs (OUT1, OUT2) of the DC / DC power converter (4), wherein, The output voltage (Vout) is a multiple of the input voltage (Vin), wherein -The DC / DC power converter (4) includes - Two switching circuits (1, 2) connected in series. - Two capacitor units (C1, C2) are connected in series, wherein the series connection of the two capacitor units (C1, C2) is connected in parallel to the series connection of the two switching circuits (1, 2), and - A resonant circuit (3) including a resonant capacitor (Cr) and a resonant inductor (Lr), wherein the resonant circuit (3) is electrically connected to the two switching circuits (1, 2). - The first capacitor unit (C1) of the two capacitor units (C1, C2) is connected in parallel to the input (IN1, IN2). - The series connection of the two switching circuits (1, 2) is connected in parallel to the output (OUT1, OUT2). - Each switching circuit (1; 2) includes two switching units (11, 12; 21, 22) connected in series, wherein each switching unit (11; 12; 21; 22) includes two or more switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) connected in series. - The first switching circuit (1) of the two switching circuits (1, 2) is electrically connected to one side of the first capacitor unit (C1), the one side of the first capacitor unit (C1) is opposite to the other side of the first capacitor unit (C1), and the other side of the first capacitor unit (C1) is connected to the second capacitor unit (C2) of the two capacitor units (C1, C2). - The switches (11a, 11b, 12a, 12b) of the first switching circuit (1) are controllable semiconductor switches; - The first capacitor unit (C1) includes two or more capacitors (C11, C12) connected in series; and - The first switching circuit (1) includes one or more diode units (D11) that electrically connect the first capacitor unit (C1) to the two switching units (11, 12) of the first switching circuit (1).

2. The DC / DC power converter (4) according to claim 1, wherein - The switches (21a, 21b, 22a, 22b) of the second switching circuit (2) in the two switching circuits (1, 2) are uncontrollable semiconductor switches; or - The switches (21a, 21b, 22a, 22b) of the second switching circuit (2) in the two switching circuits (1, 2) are controllable semiconductor switches, the second capacitor unit (C2) includes two or more capacitors (C21, C22) connected in series, and the second switching circuit (2) includes one or more diode units (D21) that electrically connect the second capacitor unit (C2) to the two switching units (21, 22) of the second switching circuit (2).

3. The DC / DC power converter (4) according to claim 1, wherein -In the case that the two or more switches (11a, 11b; 12a, 12b; 21a, 22) of each switching unit (11, 12) of the two switching circuits (1, 2) are two or more controllable semiconductor switches, The number of two or more capacitors (C11, C12; C21, C22) in the corresponding capacitor unit (C1; C2) corresponds to the number of two or more switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) in each switching unit (1, 12; 21, 22) of the switching circuit (1; 2), and - The number of one or more diode units (D11; D21) in the switching circuit (1; 2) is one less than the number of two or more switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) in each switching unit of the switching circuit (11, 12; 21, 22).

4. The DC / DC power converter (4) according to claim 2, wherein, In the case where each switching unit (11; 12; 13; 14) of the corresponding switching circuit (1; 2) includes two controllable semiconductor switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) connected in series, the corresponding switching circuit (1; 2) includes a diode unit (D11; D21), and the corresponding capacitor unit (C1; C2) includes two capacitors (C11, C12; C21, C22): - The midpoint of the series connection of the two capacitors (C11, C12; C21, C22) of the corresponding capacitor unit (C1; C2) is connected via the first diode (D11a; D21a) of the diode unit (D11; D21) to the midpoint of the series connection of the two switches (11a, 11b; 21a, 21b) of the first switching unit (11; 21) of the corresponding switching circuit (1; 2), and is connected via the second diode (D11b; D21b) of the diode unit (D11; D21) to the midpoint of the series connection of the two switches (12a, 12b; 22a, 22b) of the second switching unit (12; 22) of the corresponding switching circuit (1; 2).

5. The DC / DC power converter (4) according to claim 4, wherein - In the case where the corresponding switching circuit is the first switching circuit (1): - The corresponding capacitor unit is the first capacitor unit (C1). - The second switching unit (12) of the first switching circuit (1) is connected to the midpoint of the series electrical connection of the two switching circuits (1, 2). - The midpoint of the series connection of the two capacitors (C11, C12) of the first capacitor unit (C1) is connected to the anode of the first diode (D11a), wherein, The cathode of the first diode (D11a) is connected to the midpoint of the series electrical connection of the two switches (11a, 11b) of the first switching unit (11), and - The midpoint of the series connection of the two capacitors (C11, C12) of the first capacitor unit (C1) is connected to the cathode of the second diode (D11b), wherein the anode of the second diode (D11b) is connected to the midpoint of the series connection of the two switches (12a, 12b) of the second switching unit (12); and / or - In the case where the corresponding switching circuit is the second switching circuit (2): - The corresponding capacitor unit is the second capacitor unit (C2). - The first switching unit (21) of the second switching circuit (2) is connected to the midpoint of the series electrical connection of the two switching circuits (1, 2). - The midpoint of the series connection of the two capacitors (C21, C22) of the second capacitor unit (C2) is connected to the anode of the first diode (D21a), wherein the cathode of the first diode (D21a) is connected to the midpoint of the series connection of the two switches (21a, 21b) of the first switching unit (21), and - The midpoint of the series connection of the two capacitors (C21, C22) of the second capacitor unit (C2) is connected to the cathode of the second diode (D21b), wherein the anode of the second diode (D21b) is connected to the midpoint of the series connection of the two switches (22a, 22b) of the second switching unit (22).

6. The DC / DC power converter (4) according to claim 2, wherein, In the case where each switching unit (11; 12) of the corresponding switching circuit (1) includes three or more controllable semiconductor switches (11a, 11b, 11c; 12a, 12b, 12c) connected in series, the corresponding switching circuit (1) includes two or more diode units (D11, D12), and the corresponding capacitor unit (C1) includes three or more capacitors (C11, C12, C13): - Each node between the two capacitors (C11, C12; C12, C13) of the corresponding capacitor unit (C1) is connected via the first diode (D11a; D12a) of the corresponding diode unit (D11; D12) of the two or more diode units (D11, D12) to the first node between the two switches (11a, 11b; 11b, 11c) of the first switching unit (11) of the two switching units (11, 12) of the corresponding switching circuit (1), and via the second diode (D11b; D12b) of the corresponding diode unit (D11; D12) to the second node between the two switches (12a, 12b; 12b, 12c) of the second switching unit (12) of the two switching units (11, 12) of the corresponding switching circuit (1), wherein - The position of the first node in the series electrical connection of the three or more switches (11a, 11b, 11c) in the first switching unit (11) corresponds to the position of the second node in the series electrical connection of the three or more switches (12a, 12b, 12c) in the second switching unit (12), and - The nodes of the series electrical connection of the three or more capacitors (C11, C12, C13) of the corresponding capacitor unit (C1) are connected to different nodes of the two switching units (11, 12) of the corresponding switching circuit (1).

7. The DC / DC power converter (4) according to claim 6, wherein - In the case where the corresponding switching circuit is the first switching circuit (1): - The corresponding capacitor unit is the first capacitor unit (C1). - The second switching unit (12) of the first switching circuit (1) is connected to the midpoint of the series electrical connection of the two switching circuits (1, 2), and - Each node between the two capacitors (C11, C12; C12, C13) of the first capacitor unit (C1) is connected to - The anode of the first diode (D11a; D12a) of the corresponding diode unit (D11; D12) in one of the two or more diode units (D11, D12), wherein, The cathode of the first diode (D11a; D12a) is connected to the corresponding first node between the two switches (11a, 11b; 11b, 11c) of the first switching unit (11) in the two switching units (11, 12) of the first switching circuit (1), and - The cathode of the second diode (D11b; D12b) of the corresponding diode unit (D11; D12), wherein the anode of the second diode (D11b; D12b) is connected to the corresponding second node between the two switches (12a, 12b; 12b, 12c) of the second switch unit (12) in the two switch units (11, 12) of the first switch circuit (1); and / or - In the case where the corresponding switching circuit is the second switching circuit (2): - The corresponding capacitor unit is the second capacitor unit (C2). - The first switching unit (21) of the second switching circuit (2) is connected to the midpoint of the series electrical connection of the two switching circuits (1, 2), and - Each node between the two capacitors of the second capacitor unit (C2) is connected to - The anode of the first diode of the corresponding diode unit in one of the two or more diode units, wherein the cathode of the first diode is connected to the corresponding first node between the two switches of the first switching unit in the two switching units of the second switching circuit, and - The cathode of the second diode of the corresponding diode unit, wherein the anode of the second diode is connected to the corresponding second node between the two switches of the second switching unit in the two switching units of the second switching circuit.

8. The DC / DC power converter (4) according to claim 1. - in, The dimensions of the two or more capacitors (C11, C12) of the first capacitor unit (C1) are such that the voltage at each capacitor of the first capacitor unit (C1) corresponds to the voltage at the first capacitor unit (C1) divided by the number of capacitors in the first capacitor unit (C1).

9. The DC / DC power converter according to claim 2, - Wherein, the resonant capacitor (Cr) and the resonant inductor (Lr) are connected in series between the midpoint of the series connection of the two switching units (11, 12) of the first switching circuit (1) and the midpoint of the series connection of the two switching units (21, 22) of the second switching circuit (2); or -in - The resonant capacitor (Cr) is electrically connected between the midpoint of the series connection of the two switching units (11, 12) of the first switching circuit (1) and the midpoint of the series connection of the two switching units (21, 22) of the second switching circuit (2), and - The resonant inductor (Lr) is electrically connected between the midpoint of the series connection of the two capacitor units (C1, C2) and the midpoint of the series connection of the two switching circuits (1, 2).

10. The DC / DC power converter (4) according to claim 1, wherein - The input includes two input terminals (IN1, IN2), and the output includes two output terminals (OUT1, OUT2). - The first input terminal (IN1) of the two input terminals (IN1, IN2) and the first output terminal (OUT1) of the two output terminals (OUT1, OUT2) are electrically connected to one end of the series connection of the two capacitor units (C1, C2) and one end of the series connection of the two switching circuits (1, 2). - The second input terminal (IN2) of the two input terminals (IN1, IN2) is connected to the midpoint of the series connection of the two capacitor units (C1, C2), and - The second output terminal (OUT2) of the two output terminals (OUT1, OUT2) is connected to the other end of the series connection of the two capacitor units (C1, C2) and the other end of the series connection of the two switching circuits (1, 2).

11. The DC / DC power converter (4) according to claim 10. -The output includes a third output terminal (OUT3); -in - In the case where the resonant capacitor (Cr) and the resonant inductor (Lr) are connected in series, the third output terminal (OUT3) is electrically connected to the midpoint of the series connection of the two capacitor units (C1, C2) and the midpoint of the series connection of the two switching circuits (1, 2); or -When the resonant inductor (Lr) is electrically connected between the midpoint of the series connection of the two capacitor units (C1, C2) and the midpoint of the series connection of the two switching circuits (1, 2), the third output terminal (OUT3) is electrically connected to the midpoint of the series connection of the two capacitor units (C1, C2).

12. The DC / DC power converter (4) according to claim 2. -The DC / DC power converter (4) includes a control unit (5), and - The control unit (5) is configured to optionally and complementaryly switch the switching units (11, 12) of the first switching circuit (1) between an on state and an off state with a 50% duty cycle; and - Optionally, the control unit is configured to selectively switch the switching units (11, 12, 21, 22) of the first switching circuit (1) and the second switching circuit (2) between the on state and the off state with a duty cycle of 50%.

13. The DC / DC power converter (4) according to claim 12. -in, The control unit (5) is used to switch the corresponding switching units (11, 12; 21, 22) of the corresponding switching circuit (1; 2) between the on state and the off state by sequentially switching the switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) of each switching unit (11; 12; 21; 22).

14. The DC / DC power converter (4) according to claim 12. -in, The control unit (5) is used to complementary switch the two switching units (11, 12; 21, 22) of the corresponding switching circuit (1; 2) between the on state and the off state by alternately switching the switches (11a, 11b, 12a, 12b; 21a, 21b, 22a, 22b) of the two switching units (11, 12; 21, 22) of the corresponding switching circuit (1; 2).

15. The DC / DC power converter (4) according to claim 12. - Wherein, the control unit (5) is used to switch each of the two switching units (11, 12; 21, 22) of the corresponding switching circuit (1; 2) from the conducting state to the non-conducting state as follows: according to the position of the two or more switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) of the corresponding switching unit (11; 12) in the series electrical connection, the corresponding switching unit (11; 12) Two or more switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) of the corresponding switch unit (11; 12; 21; 22) are sequentially switched from the conducting state to the non-conducting state, such that the switch (11a; 12b; 21a; 22b) of the corresponding switch unit (11; 12; 21; 22) that is farthest from the midpoint of the series connection of the two switch units (11; 12; 21; 22) of the corresponding switch circuit (1; 2) is the first to switch from the conducting state to the non-conducting state.

16. The DC / DC power converter (4) according to claim 12. - Wherein, the control unit (5) is used to switch each of the two switching units (11, 12; 21, 22) of the corresponding switching circuit (1; 2) from the non-conducting state to the conducting state as follows: according to the position of the two or more switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) of the corresponding switching unit (11; 12b) in the series electrical connection, the corresponding switching unit (11; 12b) is switched from the non-conducting state to the conducting state. Two or more switches (11a, 11b; 12a, 12b; 21a, 21b; 22a, 22b) of the corresponding switch unit (11; 12; 21; 22) are sequentially switched from the non-conducting state to the conducting state, such that the switch (11b; 12a; 21b; 22a) at the midpoint of the series electrical connection of the two switch units (11, 12; 21, 22) of the corresponding switch circuit (1; 2) is the first to switch from the non-conducting state to the conducting state.

17. The DC / DC power converter (4) according to claim 12. -in, The control unit (5) is used to switch the switching units (11, 12, 21, 22) between the on state and the off state at a switching frequency less than or equal to the resonant frequency of the resonant circuit (3).

18. A method for controlling the switching of a DC / DC power converter (4) according to any one of claims 1 to 17, wherein - The control unit can optionally complementary switch the switching units (11, 12) of the first switching circuit (1) between an on state and an off state with a 50% duty cycle, and - Optionally, the control unit may selectively switch the switching units (11, 12, 21, 22) of the first switching circuit (1) and the second switching circuit (2) of the two switching circuits (1, 2) complementaryly between the on and off states with a 50% duty cycle.

19. A DC / DC power converter (6) comprising a cascade of multiple cascaded DC / DC power converters (41, 42, 43); - One or more of the plurality of DC / DC power converters (41; 42; 43) correspond to the DC / DC power converter (4) according to any one of claims 1 to 17. -in, Each DC / DC power converter (41; 42; 43) includes - Two switching circuits connected in series (11, 21; 12, 22; 13, 23). - Two capacitor units (C11, C21; C12, C22; C13, C23) are connected in series, wherein each capacitor unit includes one or more capacitors, and the series connection of the two capacitor units (C11, C21; C12, C22; C13, C23) is connected in parallel to the series connection of the two switching circuits (11, 21; 12, 22; 13, 23), and - A resonant circuit including resonant capacitors (Cr1; Cr2; Cr3) and resonant inductors (Lr1; Lr2; Lr3), wherein the resonant circuit is electrically connected to the two switching circuits (11, 21; 12, 22; 13, 23), wherein - The first capacitor unit (C11; C12; C13) of the two capacitor units (C11, C21; C12, C22; C13, C23) is connected in parallel to the input of the DC / DC power converter (41; 42; 43), and the series connection of the two switching circuits (11, 21; 12, 22; 13, 23) is connected in parallel to the output of the DC / DC power converter (41; 42; 43); and - wherein the output of the first DC / DC power converter (41) of the plurality of DC / DC power converters (41; 42; 43) is electrically connected to the input of the second DC / DC power converter (42) of the plurality of DC / DC power converters (41; 42; 43), such that the first capacitor unit (C12) of the second DC / DC power converter (42) is connected in parallel to the second capacitor unit (C21) of the two capacitor units (C11, C21) of the first DC / DC power converter (41).

20. The DC / DC power converter (6) according to claim 19, wherein - The input of each of the plurality of DC / DC power converters (41; 42; 43) is connected to the output of the corresponding preceding DC / DC power converter (42), such that the first capacitor cell (C13) of the corresponding other DC / DC power converter (43) is connected in parallel to the second capacitor cell (C22) of the corresponding preceding DC / DC power converter (42).

21. A system (9), wherein -The system (9) includes - DC / DC power converter (4) according to any one of claims 1 to 17, and - The power supply (7) connected to the input of the DC / DC power converter. -in, The power supply (7) is used to provide a DC input voltage (Vin) to the inputs (IN1, IN2) of the DC / DC power converter (4), and the DC / DC power converter (4) is used to convert the DC input voltage (Vin) into a DC output voltage (Vout), wherein the DC output voltage (Vout) is a multiple of the DC input voltage (Vin); or -The system (9) includes - DC / DC power converter (6) according to any one of claims 19 to 20, and - Power supply (7), which is connected to the inputs (IN1, IN2) of the DC / DC power converter (6), and in particular to the inputs (IN11, IN21) of the first DC / DC power converter (41) of the DC / DC power converter (6). - Wherein, the power supply (7) is used to provide a DC input voltage (Vin) to the input of the DC / DC power converter (6), and the DC / DC power converter (6) is used to convert the DC input voltage (Vin) into a DC output voltage (Vout), wherein the DC output voltage (Vout) is a multiple of the DC input voltage (Vin).

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