Apparatus and methods relating to power conversion using multiple rectifier circuits

Abstract

An apparatus includes a direct current (DC)-alternating current (AC) inverter circuit, first and second circuits, and an output circuit. The DC-AC inverter circuit inverts a DC input signal corresponding to an input voltage into an AC signal. The first and second circuits each include an inductive isolation circuit driven in response to power from the at least one AC signal, and a rectifier circuit that responds to the inductive isolation circuit by outputting a first rectified signal and a second rectified signal, where at least one of the first and second rectifier circuits is characterized as limited by a rated breakdown voltage. The output circuit provides a DC output voltage signal and cascades a plurality of signals including the first and second rectified signals to provide a voltage source that depends on the first and second rectified signals and is greater than the rated breakdown voltage.

Description

[0001] Overview

[0002] High-voltage (e.g., 10-100 kV) low-current (1-100 mA) power supplies can be beneficial in many applications, including medical, environmental, safety, and aerospace fields. Furthermore, the enhanced portability of high-voltage equipment can lead to new uses, better performance, and / or novel applications for this technology.

[0003] The aforementioned issues, along with others, pose challenges to power conversion in various applications. Summary of the Invention

[0004] Various embodiments are described in relation to apparatuses and / or methods involving power conversion using multiple rectifier circuits. In the following discussion, various implementations and applications are disclosed to provide an understanding of the immediate disclosure through non-limiting exemplary embodiments.

[0005] The aspects pertain to and / or involve power conversion provided by multiple stacked rectifier circuits, at least one of which has inductive isolation between a front-end section and a back-end section to enable the use of the back-end section to deliver a power conversion output stage signal with a steady-state voltage significantly greater than the voltage stress / rated breakdown voltage associated with one or more components of the front-end section.

[0006] Many aspects pertain to power converters with Class DE resonant rectifiers, which have capacitive DC (DC) isolation generating hundreds of volts. Because the rectifier diodes and output terminals are DC isolated from the input, dozens of rectifier units can be stacked, such that the output signals of these units are connected in series to generate an output voltage of several kilovolts. In this configuration, the output voltage can reach twice the rated voltage of the DC isolation capacitors because the voltage stress on the top and bottom rectifier capacitors is half the total output voltage, provided that the total isolated output voltage diverges symmetrically in both the positive and negative directions. To obtain higher output voltages, various embodiments include air-core transformers that act as additional DC isolation barriers. As described above, multiple units of multi-stage Class DE rectifiers can be cascaded. Using such example configurations, high output voltages can be generated because the achievable voltage limit is now the breakdown voltage of the inductive isolation barrier between the primary and secondary windings of the transformer.

[0007] More specifically, the invention relates to an apparatus comprising a DC-AC inverter circuit, a first circuit, a second circuit, and an output circuit. The DC-AC inverter circuit inverts at least one DC input signal corresponding to an input voltage into at least one AC signal. The first circuit includes a first inductive isolation circuit and a first rectifier circuit, the first inductive isolation circuit being driven in response to power from at least one AC signal. The first rectifier circuit responds to the first inductive isolation circuit by outputting a first rectified signal at a first pair of output terminals. The second circuit includes a second inductive isolation circuit driven in response to power from at least one AC signal and includes a second rectifier circuit. The second rectifier circuit responds to the second inductive isolation circuit by outputting a second rectified signal at a second pair of output terminals. At least one of the first and second rectifier circuits is characterized as being limited by a rated breakdown voltage. The output circuit provides a DC output voltage signal between voltage source terminals and cascades multiple signals, including the first rectified signal and the second rectified signal, by using one of the output terminals in one of the pairs of output terminals as a supply source for one of the output terminals in the other pair of output terminals. The voltage source terminals provide a voltage source that depends on the first rectified signal and the second rectified signal and is greater than the rated breakdown voltage of at least one of the first and second rectifier circuits.

[0008] In a related and more specific aspect, each of the first and second rectifier circuits includes or is configured as a Class DE rectifier and / or each of the rectifier circuits is one of a plurality of rectifier stages connected in parallel. The rated breakdown voltage is defined by a DC blocking capacitor used in the signal path of one of the first and second circuits, between the output terminal of the inductive isolation circuit and the diode in the rectifier circuit. In a specific embodiment, at least one of the first and second rectifier circuits delivers a DC output voltage signal in the associated rectified signal that is greater than twice the rated breakdown voltage of the at least one of the first and second rectifier circuits. In a more specific and related embodiment, the DC output voltage signal is three, four, five, six, or more times greater than the rated breakdown voltage.

[0009] At least one of the first and second inductive isolation circuits is associated with another rated breakdown voltage that is greater than the rated breakdown voltage of the at least one of the first and second rectifier circuits. For example, each of the first and second inductive isolation circuits includes an air-core transformer with an associated rated breakdown voltage that is greater than the rated breakdown voltage of at least one of the first and second rectifier circuits, and defines a minimum total rated breakdown voltage for the circuit included in the inductive isolation circuit.

[0010] In several related aspects, the device further includes an additional rectifier circuit having an output cascaded with the first and second rectifier circuits. Each of these rectifier circuits includes or is configured as a Class DE rectifier, isolated from the input DC voltage, and / or rated at a voltage not less than 300 volts. For example, the device further includes at least one additional circuit comprising a third circuit having a third inductive isolation circuit driven in response to power from the at least one AC signal, and including a third rectifier circuit that responds to the third inductive isolation circuit by outputting a third rectified signal at a third pair of output terminals. The output circuit provides a DC output voltage signal between voltage source terminals and cascades multiple signals including the first, second, and third rectified signals by coupling selected output terminals of the first, second, and third pairs of output terminals as cascaded supply sources, wherein the first, second, and third voltage source terminals are arranged together to provide a voltage source that depends on the first, second, and third rectified signals and is greater than the rated breakdown voltage. In such a configuration, the input terminals of the multiple rectifier circuits are connected in parallel and the output terminals are connected in series.

[0011] Other aspects relate to a DC power source for providing a DC voltage in response to at least one AC signal associated with an input voltage signal. The DC power source includes a first circuit, a second circuit, and an output circuit. The first circuit includes a first inductive isolation circuit driven in response to power from the at least one AC signal, and a first rectifier circuit that responds to the first inductive isolation circuit by outputting a first rectified signal at a first pair of output terminals; the second circuit includes a second inductive isolation circuit driven in response to power from the at least one AC signal, and a second rectifier circuit that responds to the second inductive isolation circuit by outputting a second rectified signal at a second pair of output terminals, and at least one of the first and second rectifier circuits is characterized as being limited by a rated breakdown voltage. The output circuit provides a DC output voltage signal between voltage source terminals and cascades multiple signals, including the first rectified signal and the second rectified signal, by using one of the output terminals of one of the pairs of output terminals as a supply source for the other of the pairs of output terminals. The voltage source terminals provide a voltage source that depends on the first rectified signal and the second rectified signal and is greater than the rated breakdown voltage of at least one of the first rectifier circuits and the second rectifier circuit.

[0012] As described above, each of the first and second inductive isolation circuits includes an air-core transformer having an additional rated breakdown voltage associated with the material between the air-core transformer windings, and this additional rated breakdown voltage is greater than the rated breakdown voltage of at least one of the first and second rectifier circuits. The at least one of the first and second rectifier circuits includes a DC blocking capacitor used in the signal path of one of the first and second circuits, between the output terminal of the inductive isolation circuit and a diode in the rectifier circuit. The DC blocking capacitor is characterized as being limited by a rated breakdown voltage. The device may further include a plurality of circuits, including a first and second circuit cascaded between voltage rails, with at least one of the first and second rectifier circuits located closest to one of the voltage rails.

[0013] In many related and more specific embodiments, the DC power source and / or the apparatus including the DC power source further includes a front-end driver circuit that provides the at least one AC signal to the first inductive isolation circuit and the second inductive isolation circuit. In a more specific aspect, the front-end driver circuit includes one or more DC-AC inverter circuits configured and arranged to invert at least one DC input signal corresponding to the input voltage signal into the at least one AC signal, and drive the first inductive isolation circuit and the second inductive isolation circuit via the at least one AC signal. In other aspects, the front-end driver circuit includes one or more AC-AC inverter circuits configured and arranged to invert at least one AC input signal corresponding to the input voltage signal and a first frequency into the at least one AC signal corresponding to a second frequency, and drive the first inductive isolation circuit and the second inductive isolation circuit via the at least one AC signal at the second frequency.

[0014] Several aspects relate to a method of power conversion using one or more of the aforementioned devices. The method includes: providing at least one alternating current (AC) signal from a direct current (DC) voltage input signal; and using a first circuit and a second circuit in parallel, each circuit providing inductive isolation and each circuit being driven in response to power from the at least one AC signal, and each circuit rectifying by outputting a rectified signal at an associated pair of output terminals in response to the inductive isolation. The rectification associated with at least one of the first circuit and the second circuit is associated with a circuit characterized as being limited by a rated breakdown voltage. The method further includes providing a DC output voltage signal between voltage source terminals by cascading a plurality of signals including the rectified signal, wherein the DC output voltage signal depends on the rectified signal and is greater than the rated breakdown voltage.

[0015] Therefore, various embodiments are designed to address the challenges associated with the foregoing and other aspects, which may be beneficial to various power converters and / or multistage rectifiers. The foregoing discussion / summary is not intended to describe every embodiment or implementation of this disclosure. Various embodiments are also illustrated in the following figures and detailed description. Attached Figure Description

[0016] Various exemplary embodiments can be more fully understood in light of the following detailed description taken in conjunction with the accompanying drawings, wherein: Figure 1 Examples of apparatuses relating to power conversion according to various embodiments of the present disclosure are shown; Figures 2A-2B Another example of a power conversion apparatus according to various embodiments of the present disclosure is shown; Figure 3 Example front-end driver circuits of devices according to various embodiments of the present invention are shown; Figures 4A-4C Experimental examples of inductive isolation circuits for devices according to various embodiments of the present invention are shown; Figures 5A-5B Experimental examples of multi-stage rectifiers according to various embodiments of the present invention are shown; Figures 6A-6C Example experimental results of power converters according to various embodiments of this disclosure are shown; Figures 7A-7D Example experimental results of another power converter according to various embodiments of this disclosure are shown; Figures 8A-8B Example experimental performance results of another power converter according to various embodiments of this disclosure are shown; Figure 9 Examples of computed tomography (CT) scanner gantrys with devices according to various embodiments are shown; and Figure 10 An example traveling wave tube (TWT) radar power supply according to various embodiments is shown.

[0017] While the various embodiments discussed herein are adaptable to modifications and alternatives, aspects thereof have been shown by way of example in the accompanying drawings and will be described in detail. However, it should be understood that the disclosure is not intended to be limited to the specific embodiments described. Rather, it is intended to cover all modifications, equivalents, and alternatives within the scope of this disclosure, including aspects as defined in the claims. Furthermore, the term "example" as used herein is for illustrative purposes only and not for limitation. Detailed Implementation

[0018] The aspects of this disclosure are intended for use in various types of apparatuses, systems, and methods involving power conversion using multiple rectifier circuits. In specific embodiments, the voltage output by the power conversion device is greater than twice the rated breakdown voltage of a capacitor in a stacked cascade of multiple rectifier circuits. While the invention is not necessarily limited to such applications, various aspects of the invention can be appreciated through the discussion of various examples in this context.

[0019] Therefore, various specific details are set forth in the following description to describe the specific examples presented herein. However, it will be apparent to those skilled in the art that one or more other examples and / or variations of these examples may be practiced without all the specific details given below. In other instances, well-known features have not been described in detail to avoid obscuring the description of the examples herein. For ease of illustration, the same reference numerals may be used in different figures to denote the same elements or additional instances of the same elements. Furthermore, although aspects and features may be described in a single figure in some cases, it should be understood that features from one figure or embodiment may be combined with features from another figure or embodiment, even if the combination is not explicitly shown or described as a combination.

[0020] Specific example embodiments pertain to a power converter with multiple stacked rectifier circuits having inductive isolation. For example, at least one of the rectifier circuits has inductive isolation between a front-end section and a back-end section, enabling the back-end section to be used to deliver a power conversion output stage signal having a steady-state voltage significantly greater than the rated breakdown voltage associated with one or more components of the back-end section. The one or more components may include one or more DC blocking capacitors of the rectifier circuit that provide DC isolation to the rectifier diodes. Inductive isolation circuitry (such as an air-core transformer) between the front-end and back-end sections provides further inductive isolation. The front-end section herein refers to a "front-end driver circuit." The back-end section includes multiple rectifier circuits. The inductive isolation circuitry can increase the maximum output voltage of the power conversion circuitry compared to the rated breakdown voltage associated with one or more components of the back-end section. For example, embodiments may include inductively isolating the front-end driver circuitry from the rectifier circuitry while using the rectifier circuitry to deliver a power conversion output stage signal having a steady-state voltage greater than twice the rated breakdown voltage associated with a component of each rectifier circuitry. Such embodiments may include the use of multiple rectifier circuits arranged in cascade between voltage rails, wherein at least one of the two rectifier circuits is located closest to the voltage rail.

[0021] Some embodiments address challenges associated with high DC voltages. Various systems, devices, and / or methods can benefit from high DC voltages in the tens of kilovolts (kV) or higher range. To enhance portability without compromising performance, as described below and in many other devices, small, lightweight, and high-power power supplies are typically used. As further described herein, various embodiments are directed to small, lightweight, high-voltage power (e.g., DC-DC) converters with fast transient response that can be used in a variety of applications. Some example systems, devices, and / or methods include electrostatic precipitators (ESPs), X-ray sources and neutron generators for airport security, regulations, and explosives detection, and medical devices such as dental X-ray or computed tomography (CT) scanners.

[0022] Certain aspects of this disclosure relate to power conversion provided by multiple stacked rectifier circuits, such as multi-stage Class DE rectifiers with inductive isolation exceeding the limitations set by the capacitor rating voltage of the Class DE rectifier. The insertion of an air-core transformer enhances the DC voltage blocking capability against breakdown voltages of the material between the transformer windings. Furthermore, the parallel connection of these stages enables a fast rise time, making the circuit particularly suitable for systems requiring pulsed DC voltages. Various embodiments include multiple stacked rectifier circuits, such as multi-stage Class DE rectifiers that allow all input terminals (or ports) of the rectifier to be connected in parallel and the output terminals (or ports) to be connected in series, thereby delivering current from the input to each node simultaneously. In such configurations, the maximum number of rectifier stages that can be cascaded is limited by the rated voltage of the DC blocking capacitors at the top and bottom stages; therefore, the output voltage of the converter must not exceed twice the rated voltage of the capacitors. More specific embodiments of this disclosure relate to multiple stacked rectifier circuits with inductive isolation that breaks the limitations set by the capacitor rating voltage. The insertion of an air-core transformer enhances the DC voltage blocking capability against breakdown voltages of the material between the transformer windings. Furthermore, the parallel connection of these stages enables a fast rise time, making the circuit particularly suitable for systems that require pulsed DC voltages.

[0023] Specific example embodiments relate to methods and / or apparatuses including and / or involving devices comprising a DC-AC inverter circuit, a first circuit, a second circuit, and an output circuit. The DC-AC inverter circuit inverts at least one DC input signal corresponding to an input voltage into at least one AC signal. The first circuit includes a first inductive isolation circuit and a first rectifier circuit, the first inductive isolation circuit being driven in response to power from at least one AC signal. The first rectifier circuit responds to the first inductive isolation circuit by outputting a first rectified signal at a first pair of output terminals. The second circuit includes a second inductive isolation circuit driven in response to power from at least one AC signal and includes a second rectifier circuit. The second rectifier circuit responds to the second inductive isolation circuit by outputting a second rectified signal at a second pair of output terminals. At least one of the first rectifier circuit and the second rectifier circuit is characterized as being limited by a rated breakdown voltage. The output circuit provides a DC output voltage signal between voltage source terminals and cascades multiple signals, including a first rectified signal and a second rectified signal, by using one of the output terminals in one of the pairs of output terminals as a supply source for one of the output terminals in the other pair of output terminals. The voltage source terminals provide a voltage source that depends on the first rectified signal and the second rectified signal and is greater than the rated breakdown voltage of at least one of the first rectifier circuit and the second rectifier circuit.

[0024] In related and more specific embodiments, each of the rectifier circuits includes or is configured as a Class DE rectifier and / or each of the rectifier circuits is one of a plurality of rectifier stages connected in parallel. The rated breakdown voltage is defined by a DC blocking capacitor used in the signal path of one of the first and second circuits, between the output terminal of the inductive isolation circuit and the diode in the rectifier circuit. In a specific embodiment, at least one rectifier circuit delivers a DC output voltage signal in the associated rectified signal that is greater than twice the rated breakdown voltage of the at least one rectifier circuit in the first and second rectifier circuits.

[0025] At least one of the inductive isolation circuits may be associated with another rated breakdown voltage that is greater than the rated breakdown voltage of at least one of the first and second rectifier circuits. For example, each of the first and second inductive isolation circuits includes an air-core transformer with an associated rated breakdown voltage that is greater than the rated breakdown voltage of at least one of the first and second rectifier circuits, and defines a minimum total rated breakdown voltage for the circuits included in the inductive isolation circuit.

[0026] The apparatus described above may further include an additional rectifier circuit having an output cascaded with the first and second rectifier circuits. Each of the rectifier circuits includes or is configured as a Class DE rectifier, isolated from the input DC voltage, and / or rated at a voltage not less than 300 volts. For example, the apparatus further includes at least one additional circuit comprising a third circuit having a third inductive isolation circuit driven in response to power from at least one AC signal, and including a third rectifier circuit that responds to the third inductive isolation circuit by outputting a third rectified signal at a third pair of output terminals. The output circuit provides a DC output voltage signal between voltage source terminals and cascades multiple signals including the first, second, and third rectified signals by coupling selected output terminals of the first, second, and third pairs of output terminals as cascaded supply sources, wherein the first, second, and third voltage source terminals are arranged together to provide a voltage source that depends on the first, second, and third rectified signals and is greater than the rated breakdown voltage.

[0027] Other embodiments pertain to a DC power source for providing a DC voltage in response to at least one AC signal associated with an input voltage signal. The DC power source includes the first circuit, second circuit, and output circuit described above. As described above, the first and second inductive isolation circuits may each include an air-core transformer having an additional rated breakdown voltage associated with the material between the air-core transformer windings, and this additional rated breakdown voltage is greater than the rated breakdown voltage of at least one of the first and second rectifier circuits. At least one of the first and second rectifier circuits includes a DC blocking capacitor used in the signal path of one of the first and second circuits, the DC blocking capacitor being characterized as being limited by a rated breakdown voltage. The device may further include a plurality of circuits including a first and second circuit cascaded between voltage rails, with at least one of the first and second rectifier circuits located closest to one of the voltage rails.

[0028] In many related and more specific embodiments, the device further includes a front-end driver circuit that provides at least one AC signal to the first inductive isolation circuit and the second inductive isolation circuit. The front-end driver circuit may include one or more DC-AC inverter circuits that invert at least one DC input signal corresponding to an input voltage into at least one AC signal, and drive the first and second inductive isolation circuits via the at least one AC signal. In other embodiments, the front-end driver circuit includes one or more AC-AC inverter circuits that invert at least one AC input signal corresponding to a first frequency (and input voltage) into at least one AC signal corresponding to a second frequency, and drive the first and second inductive isolation circuits via the at least one AC signal at the second frequency.

[0029] One or more embodiments relate to systems and / or methods involving a computed tomography (CT) scanner gantry and other devices having high-speed rotating components (e.g., centrifugal devices) such as rotating gantry components. The CT scanner relates to the power converter described above. The CT scanner is designed and / or configured based on the power conversion circuitry and its weight, which allows for faster rotation speeds, with its upper limit at least partially limited by the power conversion circuitry used to supply power to it. For example, the overall specifications of the CT scanner and its weight are associated with a specific rotation speed of the gantry rotation. Faster rotation speeds, combined with shorter output voltage rise and fall times, can result in reduced radiation exposure to the patient because the faster rotation speed exposes the patient to radiation (e.g., localized radiation) for shorter periods.

[0030] One or more other embodiments relate to a machine that includes a traveling wave tube (TWT) radar power supply with the power conversion circuitry described above. The power conversion circuitry can reduce the overall system size, thereby allowing the use of more powerful radar systems in mobile applications, or placing such radars in smaller vehicles (e.g., drones, cars, etc.) that were previously too large due to system size and weight. For example, the weight of the machine depends on the weight associated with the power conversion circuitry used to power the circuitry used to provide electrostatic adhesion.

[0031] As will be understood by those skilled in the art, the embodiments are not limited to the systems and / or methods listed above. Other example systems and / or methods involving the power conversion described above may include electrostatic sprayers, electrohydraulic propulsion systems, high-power laser power supplies, taser guns, particle accelerators, plasma generators, capacitor charging, and ozone generation, among other types of systems and / or methods. Some embodiments include or relate to a medical system (e.g., an X-ray transmitter) comprising a gantry capable of delivering a voltage-based radiation dose to a patient, the medical system being designed / configured to be configured to rotate the gantry at a high speed, its upper limit speed limited at least in part by the power conversion circuitry, wherein the radiation dose is at least partially specified by the upper limit speed of the gantry. Other embodiments include or relate to ion source machines (e.g., X-ray emitters, linear accelerators, neutron generators for bomb detection, drill bits / systems configured for oil well logging and geological exploration) comprising voltage-based components or voltage-based racks, the ion source machine being configured and arranged for portability, and wherein the weight of the portable machine depends on the weight associated with power conversion circuitry used to achieve rotation of the voltage-based components or voltage-based racks. Additional embodiments include or relate to machines configured to provide electrostatic adhesion, wherein the weight of the machine depends on the weight associated with power conversion circuitry used to supply power to circuitry used to provide electrostatic adhesion.

[0032] As further described herein, the above-described apparatus can be used to implement a variety of methods for power conversion.

[0033] Now turn to the attached image. Figure 1 Examples of power conversion apparatus according to various embodiments of the present disclosure are shown. As shown, the apparatus includes a front-end driver circuit 102, a first circuit and a second circuit (described further below), and an output circuit 112. In various embodiments, the apparatus includes a power converter comprising an inverter circuit, an inductive isolation circuit, and a rectifier circuit arranged in a cascaded manner. As further described herein, the first circuit and the second circuit include inductive isolation circuits 104 and 108 and rectifier circuits 106 and 110, respectively.

[0034] The front-end driver circuit 102 presents an oscillating signal (such as one or more AC signals) to the inductor isolation circuits 104, 108. In a specific embodiment, the front-end driver circuit 102 includes presenting at least one DC input signal (e.g., V) corresponding to the input voltage. DDOne or more DC-AC inverter circuits 103, 105 invert an input AC signal to at least one AC signal. Although shown in a one-to-one correspondence with subsequent stages (e.g., first and second circuits), the embodiments are not limited thereto. The at least one AC signal is used to drive the first and second circuits. Additionally, the embodiments are not limited to DC-AC inverter circuits. For example, the front-end driver circuit 102 may include circuitry that provides an oscillation signal. In some specific embodiments, the front-end driver circuit 102 includes one or more AC-AC inverter circuits that invert an input AC signal at a first frequency to an output AC signal at a second frequency. In other embodiments and / or additionally, the front-end driver circuit 102 directly derives an AC signal.

[0035] Each of the first and second circuits includes a respective inductive isolation circuit 104, 108 and rectifier circuit 106, 110. For example, the first circuit includes a first inductive isolation circuit 104 and a first rectifier circuit 106, the first inductive isolation circuit 104 being driven in response to power from at least one AC signal. The first rectifier circuit 106 responds to the first inductive isolation circuit 104 by outputting a first rectified signal at a first pair of output terminals. The second circuit includes a second inductive isolation circuit 108 and a second rectifier circuit 110, the second inductive isolation circuit 108 being driven in response to power from at least one AC signal, and the second rectifier circuit 110 responding to the second inductive isolation circuit 108 by outputting a second rectified signal at a second pair of output terminals. As further illustrated herein, the first rectifier circuit and / or the second rectifier circuit 106, 110 include one or more DC blocking capacitors used in the signal path of one of the first and second circuits, between the output terminals of the inductor isolation circuits 104 and / or 108 and the diodes in the rectifier circuits 106 and / or 110. For example, the first and / or second rectifier circuits 106, 110 are configured as Class DE rectifiers. In such embodiments, the first and / or second circuits are characterized as being limited by a rated breakdown voltage, which may be associated with the DC blocking capacitor. As can be understood and further described herein, the capacitor may have a rated breakdown voltage that defines the breakdown of the capacitor.

[0036] The first and second inductive isolation circuits 104, 108 include transformers, such as air-core transformers. One or more of the first and second inductive isolation circuits 104, 108 are associated with another breakdown voltage that is greater than the rated breakdown voltage of at least one rectifier circuit of the first and second rectifier circuits 106, 110 and / or defines the minimum total breakdown voltage of the circuits included in the first and second inductive isolation circuits 104, 108.

[0037] The rectifier circuits may be arranged in a cascaded configuration, and the output circuit 112 implements or provides a cascaded connection between the rectifier circuits 106 and 110. As used herein, the output circuit 112 includes or refers to at least wires for implementing the cascaded connection of the rectifier circuits. For example, the output circuit 112 provides a DC output voltage signal between voltage source terminals and cascades multiple signals, including a first rectified signal and a second rectified signal, by using one of the pairs of output terminals as a supply source for one of the other pairs of output terminals. The voltage source terminals provide a voltage source that depends on the first rectified signal and the second rectified signal and is greater than the rated breakdown voltage of at least one of the first and second rectifier circuits. As further described herein, at least one of the rectifier circuits 106 and 110 may deliver a DC output voltage signal in the associated rectified signal that is greater than twice the rated breakdown voltage of at least one of the first and second rectifier circuits.

[0038] In a specific embodiment, each of the rectifier circuits 106 and 110 is one of a plurality of rectifier stages connected via the output circuit 112. For example, the input terminals are connected in parallel, while the output terminals are connected in series. Although Figure 1 The embodiments illustrate two stages (e.g., two rectifiers), but the embodiments are not limited thereto. For example, the device may further include an additional rectifier circuit having outputs cascaded with the first and second rectifier circuits 106, 110. Each of the rectifier circuits includes or is configured as a Class DE rectifier, isolated from the input DC voltage, and / or rated at a voltage not less than 300 volts. As a more specific example, the device may include at least one additional circuit including a third circuit having a third inductive isolation circuit driven in response to power from at least one AC signal and including a third rectifier circuit that responds to the third inductive isolation circuit by outputting a third rectified signal at a third pair of output terminals. Output circuit 112 provides a DC output voltage signal between voltage source terminals and cascades multiple signals including the first, second, and third rectified signals by coupling selected output terminals of the first, second, and third pairs of output terminals as cascaded supply sources, wherein the first, second, and third voltage source terminals are arranged together to provide a voltage source that depends on the first, second, and third rectified signals and is greater than the rated breakdown voltage.

[0039] although Figure 1The embodiments shown include a device including front-end driver circuitry 102, but the embodiments are not limited thereto. For example, the device may include a DC power source for providing a DC voltage in response to at least one AC signal associated with an input voltage signal. The DC power source includes the first circuitry described above (e.g., the first inductor isolation circuitry 104 and the first rectifier circuitry 106), the second circuitry (e.g., the second inductor isolation circuitry 108 and the second rectifier circuitry), and the output circuitry 112, as previously described. Figure 1 As described and shown.

[0040] The aforementioned device may include a power converter comprising one or more rectifier circuits with inductive isolation, which overcomes the limitations imposed by the capacitor's rated voltage. The use of an air-core transformer enhances the DC voltage blocking capability against breakdown voltages of the materials between the transformer windings. Furthermore, the parallel connection of these rectifier stages provides sufficient rise time, making the circuit suitable for systems requiring pulsed DC voltages.

[0041] Figures 2A-2B Another example of a power conversion apparatus according to various embodiments of the present disclosure is shown. Figure 1 Similar to what is shown, Figure 2A The device shown includes an inverter circuit 220, an inductive isolation circuit 222, and multiple rectifier circuits 224-1, 224-2 ... 224-N (referred to herein as “rectifier circuit 224” for ease of reference).

[0042] The rectifier circuit 224 can be arranged as a multi-stage Class DE rectifier. Each rectifier circuit 224 is connected via an output circuit that is connected in parallel to the input terminals (or ports) of the rectifier and in series to the output terminals (or ports), thereby simultaneously delivering current from the input to each of the rectifier circuits 224. Therefore, the rectifier circuits are arranged in a cascaded configuration. The device may include multiple circuits, including... Figure 1 The diagram shows a first and second circuit arranged in cascade between voltage rails. At least the circuits are located closest to the voltage rails, and in some embodiments, all circuits may include a Class DE rectifier with at least one DC blocking capacitor coupled to an air-core transformer for further isolation. In a specific embodiment, the rectifier circuits in the stack may have parallel-connected input ports / terminals and series-connected output terminals (e.g., via output circuitry).

[0043] Figure 2BAn example of a Class DE rectifier 224-2 with output circuitry is shown. As illustrated, the Class DE rectifier includes one or more DC blocking capacitors that isolate the rectifier diodes when the rectifier circuit 224 outputs a DC output voltage signal. More specifically, the DC blocking capacitors are used in the signal path of one or more of the first and second circuits, between the output terminal of the inductive isolation circuit and the diodes in the rectifier circuit. Because the rectifier diodes and output terminals are isolated from the input DC, multiple units of the rectifier are stacked such that the rectifier output terminals are connected in series and used to provide a specific voltage output. In some embodiments, twenty 300V rectifiers are stacked to provide a 6kV voltage output, but the embodiments are not limited thereto. As described above, the DC blocking capacitors are characterized by their rated breakdown voltage.

[0044] According to various embodiments, the number of cascaded rectifier stages is not limited by the rated breakdown voltage of the DC blocking capacitors at one or more stages (such as at the top and bottom stages), so the output voltage of the power converter can exceed twice the rated breakdown voltage of the corresponding capacitors of one or more rectifier circuits 224. In specific embodiments, including those described above, the output voltage V is increased because the inductive isolation circuit 222 provides additional DC isolation. 出 It can be larger than the DC isolation capacitor C shown in Figure 2. Bt and C Bb The output voltage is twice the rated voltage. To obtain a higher output voltage, various embodiments include an air-core transformer, which acts as an additional DC isolation barrier. Without additional DC isolation, the output voltage V... 出 Up to DC isolation capacitor C Bt and C Bb Twice the rated voltage, because (e.g.) Figure 2A The voltage stress on the capacitors of the stacked (top and bottom rectifiers) shown is half the total output voltage, provided that the total output voltage of this isolation diverges symmetrically in the positive and negative directions. Typically, when the number of cascaded DE-class rectifiers is N and the DC blocking capacitance is much larger than the diode junction capacitance, the voltage stress on the nth stage capacitor is expressed as: Voltage stress ,in ,as well as Voltage stress ,in, .

[0045] As a specific example, suppose Figure 2B The DC blocking capacitors in the components are rated to withstand +5kV and -5kV respectively. When not using... Figure 2AWith the additional DC isolation provided by the inductive isolation circuit 222, the total output voltage of the multi-stage rectifier cannot exceed 10kV when the capacitors of the top and bottom rectifiers are not operated under voltage stress of 5kV or greater, regardless of the number of rectifier stages connected. The additional DC isolation provided by the inductive isolation circuit 222 allows the multi-stage rectifier to exceed 10kV by cascading multiple units of the multi-stage Class DE rectifier. Using this configuration, a high output voltage (e.g., greater than twice the rated breakdown voltage of the capacitor) is provided. Now, the limitation on the achievable voltage is the breakdown voltage of the inductive isolation barrier between the primary and secondary windings of the transformer. In specific embodiments, the achievable voltage (e.g., the DC output voltage signal) can be two, three, four, five, six, or more times greater than the rated breakdown voltage.

[0046] According to the various embodiments described above, the device can be used to implement various methods. One example method includes: providing at least one AC signal from a DC voltage input signal, and using a first circuit and a second circuit in parallel, each circuit providing inductive isolation and each circuit being driven in response to power from the at least one AC signal, and each circuit rectifying by outputting a rectified signal at an associated pair of output terminals in response to the inductive isolation. As described above, the respective rectifier circuits are connected via output circuits connected in parallel to the input terminals of the rectifiers and in series to the output terminals. The rectification associated with at least one of the first and second circuits is associated with a circuit characterized as being limited by a rated breakdown voltage. The method further includes providing a DC output voltage signal between voltage source terminals by cascading multiple signals including (e.g., first and second) rectified signals, wherein the DC output voltage signal depends on the rectified signal and is greater than the rated breakdown voltage.

[0047] Additionally, the apparatus described above can be used in a variety of applications, such as various systems, devices, and / or methods. Some example systems, devices, and / or methods include electrostatic precipitators (ESPs), X-ray sources and neutron generators for airport security, regulations, and explosives detection, and medical devices such as dental X-ray or computed tomography (CT) scanners.

[0048] As a concrete example, an ESP is an air filtration device that uses high voltage to electrostatically charge dust particles to subsequently remove them. ESPs represent a viable solution to the problem of indoor air pollution, which causes 4.3 million deaths annually. ESP designs using power converters according to various embodiments can occupy less space and / or require lower power supplies, allowing for the miniaturization and utilization of ESPs in rural areas of developing countries.

[0049] CT scanners include another specific example. To acquire images of the human body, CT scanners use X-rays generated from a high electric field. CT scans expose patients to potentially harmful radiation. While radiation levels can be reduced using fast-pulsed X-ray sources, CT scanners using power converters according to various embodiments can provide sufficiently fast rise and fall times (e.g., 10 to 100 μs). Such example CT scanners can reduce the CT scan time required per patient in a clinical setting as the scanner rotates faster, and also reduce mechanical stress on the rotating components. In such embodiments, the weight and size of the electronics mounted thereon are reduced, which allows the system to rotate faster and reduces scan time.

[0050] Another concrete example is electrohydrodynamic (EHD) ion-propelled aircraft. EHD ion-propelled aircraft are an emerging aerospace application where thrust is generated by ionizing air molecules through multiple electrode pairs. EHD could potentially lead to silent unmanned aerial vehicles, which could prove useful in military environments. To achieve this, the power source used is light enough to fly, yet can simultaneously provide hundreds of watts of power and a voltage approaching 100 kV to the aircraft.

[0051] Other systems, devices, and / or methods may include high-power electronic equipment used in security scanners employing X-ray, ion, and neutron sources. Such scanners can be used for cargo inspection at airports, borders, checkpoints, etc. If made into handheld devices, such scanners could be useful for bomb disposal technicians or law enforcement personnel, such as border security officers. High-performance neutron generators can also benefit the oil industry, as they are widely used in oil well logging operations.

[0052] The embodiments are not limited thereto, and may include a variety of applications related to small, lightweight and fast transient response high voltage power (e.g., DC-DC) converters and / or methods thereof.

[0053] More detailed / experimental examples

[0054] As described above, the various embodiments are directed to devices involving power conversion. In specific embodiments, the device has multiple stacked rectifier circuits (e.g., multi-stage DE rectifiers in series, such as...). Figure 2B The device may include an air-core transformer that serves as an additional DC isolation barrier, as described above and further shown in Appendix A of the provisional appendix below. Figure 2BAn example 300V Class DE resonant rectifier with capacitive DC isolation is shown, which can be used in high-voltage generators. Because the rectifier diodes and output terminals are DC isolated from the input, multiple units of the 300V rectifier (e.g., 20 units) can be stacked, such as... Figure 2B As shown in Appendix A, to produce a 6kV voltage output. Use as follows... Figure 2A The example device shown can generate a high output voltage because the limitation on the achievable voltage is now the breakdown voltage of the inductive isolation barrier between the primary and secondary windings of the transformer.

[0055] In various specific embodiments, as described herein, the device may include inverter circuitry that converts a DC input to a high-frequency AC voltage. The device may include a full-bridge resonant inverter implemented for a DC-AC stage. Various embodiments are directed to devices having inverter circuitry, multiple stacked rectifier circuits, and transformer circuitry. Figure 4A Appendix A further illustrates an example of PCB transformer design.

[0056] Various experimental embodiments are designed for multi-stage Class DE rectifier structures with inductive isolation. High-frequency operation allows for a fast transient response of the output voltage. The use of an input-parallel, output-series structure with an air-core PCB transformer having high DC voltage blocking capability results in a high achievable output voltage for the DC-DC converter. At a switching frequency of 1.25 MHz, a 60V-6kV DC-DC converter has been shown to deliver 36W of power to a load, and a high-gain DC-DC converter in a multi-stage configuration delivers 35kV and 203 watts (W) of power to a load while maintaining 73% efficiency and can pulse output with a rise time of 296 microseconds (µs).

[0057] Figure 3 Example front-end driver circuits of devices according to various embodiments of the present invention are shown. As previously described, the front-end driver circuit 330 provides at least one AC signal to a first inductive isolation circuit and a second inductive isolation circuit, thereby driving the respective first and second inductive isolation circuits. As previously described, the front-end driver circuit 330 may include one or more DC-AC inverter circuits or one or more AC-AC inverter circuits.

[0058] like Figure 3 As illustrated in the specific example, the front-end driver circuit 330 includes a DC-AC inverter that uses a gate driver (e.g., a gate signal generator) 331 and a power stage 333 to convert a DC input into a high-frequency AC voltage. The DC-AC inverter is coupled to at least a portion of an inductive isolation circuit 335, which is referred to herein as the "main stage side".

[0059] like Figure 3 As shown, the DC-AC inverter is a full-bridge resonant inverter used in the DC-AC stage. Due to the DC input V... DD For a voltage of 60V, in a specific embodiment, two 80V half-bridge circuits are used to form a full bridge. Each half-bridge can be implemented using a GaN power stage 333 with an integrated gate driver 331. To maintain symmetry, the resonant capacitance is provided by two series capacitors. Based on the printed circuit board (PCB) planner transformer parameters, as further shown below, in a specific embodiment, the series leakage inductance on the main stage side is 1.7 microhenries (µH). To provide a series resonant frequency of 1 MHz (MH), the series resonant capacitance is 15 nanofarads (nF), and each of the capacitors Cs is 30nF. For each Cs, a 22nF ceramic capacitor and an 8.2nF ceramic capacitor can be connected in parallel. The low-voltage input signal from the timing circuit is isolated from the GaN half-bridge module using a digital isolator. An isolated 5V voltage is provided for the time-delay and pulse circuits using a push-pull transformer driver. Based on various experimental embodiments, Tables I and II of the Basic Provisional Appendix A provide example inverter designs with isolated 5V power supplies and example transformer layouts, and this application is not limited thereto.

[0060] Figures 4A-4C Example inductive isolation circuits of devices according to various embodiments of the present invention are shown. More specifically, Figure 4A An example PCB layout 450 for a transformer is shown for both the primary-side winding (e.g., the front-end driver side) and the secondary-side winding (e.g., the rectifier side). As will be understood, the transformer can be a coupled coil model. The transformer comprises an air-core planar PCB transformer providing inductive isolation. Both the PCB layouts for the primary winding on the inverter side and the secondary winding on the rectifier side include top copper, bottom copper, and vias. Table II of the basically provisional Appendix A lists the geometric parameters of the transformer layout.

[0061] like Figure 4AAs shown, a specific cross-sectional view of the transformer illustrates the placement of 3 mil (76.2 µm) thick Kapton sheets, each with a rated dielectric strength of 4.5 kV / mil. In a specific experimental embodiment, as further described herein, four 3 mil (76.2 µm) Kapton sheets are used between two transformer windings to provide 54 kV DC blocking capability. The top two Kapton sheets cover the bottom side of the rectifier to prevent or mitigate arcing between rectifiers when the DC-DC converters are stacked. Similarly, the bottom two Kapton sheets are bent to cover the bottom side of the inverter to provide DC blocking between the inverter and the primary windings of the DC-DC converter in a multi-stage configuration. Two ounces of copper (71 micrometers) can be used for the trace implementation. Generally, thicker copper is used because the AC resistance of the transformer windings at megahertz frequencies is inversely proportional to the copper thickness. This is because current at high frequencies concentrates towards the inside of the copper trace.

[0062] In a specific experimental embodiment, the circuit board and the Capton sheet are secured together with nylon screws and nuts. To prevent or mitigate arcing through the screw holes, these holes are filled with a high-voltage insulating coating. By following this design, transformers with Lp=7:1µH, Ls=99:7µH, and k=0:87 can be obtained. Figure 4B The model of the coupled inductor is shown, and Figure 4C The equivalent leakage inductance and magnetizing inductance model of the transformer is shown.

[0063] Figures 5A-5B Experimental examples of multi-stage rectifiers based on various embodiments of the invention are shown. More specifically, Figures 5A-5B An example of a 20-stage cascaded Class DE rectifier for 6kV DC output is shown. Figure 5A It's PCB layout, and Figure 5B These are images from an experimental example. Figures 5A-5B The 20-stage cascaded Class DE rectifier shown includes DC blocking capacitors, such as those previously provided by... Figure 2B C shown Bt and C Bb In a specific experimental embodiment, the DC blocking capacitor is a 33 picofarad (pF) x 1 x 2 rated capacitor. For diodes, such as Figure 2B Those diodes marked D are two 240 V Si Schottky diodes connected in series as a single 480 V rated rectifier. Table III of Appendix A, which is basically provisional, lists the part numbers of the components.

[0064] Various experimental embodiments are provided for 60V-6kV power converters, 60V-24kV power converters, 60V-30kV power converters, and 60V-35kV power converters. The rectifier can be single-stage or cascaded. In specific experimental embodiments, the 60V-6kV power converter can be 6 inches × 2 inches (e.g., 15cm × 5cm). The 60V-35kV DC-DC converter is implemented by stacking six 60V-6kV DC-DC converters, and multi-stage cascaded converters are also possible.

[0065] In various embodiments, a 60V radio frequency (RF) inverter, a transformer, and an RF-6kV rectifier previously described for manufacturing a 60V-6kV DC-DC converter are combined. Insulating varnish may be applied to the screw holes.

[0066] Additionally, multiple 60V-6kV DC-DC converters can be stacked in a multi-stage configuration. Four to six stages of DC-DC converters can be stacked. Multiple units of 6kV rectifiers are connected in series, and 60V inverters are connected in parallel. An example experimental six-stage converter measures 8 inches × 2.5 inches × 2 inches (20 cm × 6 cm × 5 cm) in width, length, and height. The converter weighs 188g, but the embodiments are not limited to this.

[0067] Various experimental embodiments involve power supplies, probes, and oscilloscopes connected to the DC-DC power converter under test. Because the experiments involve high voltages in the tens of kV range, special care is taken to ensure that personnel are not exposed to any electrical or physical hazards. The high-voltage DC-DC converter and load are short-circuited to nearby water pipes via a grounded Faraday cage. Additionally, an acrylic sheet is placed between the personnel and the high-voltage converter to prevent injury from flying sparks or debris in the event of a catastrophic failure (which may not occur). A differential probe (model CT4079; manufactured by Elditest) capable of measuring voltages up to ±15 kV is used. Due to the voltage rating limitations of the probe, voltage measurements are performed using one or two resistor units of a resistor chain (each resistor unit is 1 MΩ). The measured voltage is amplified proportionally to the voltage division ratio to estimate the end-to-end voltage applied to the resistor chain.

[0068] Figures 6A-6C Example experimental results of power converters according to various embodiments of this disclosure are shown. More specifically, Figures 6A-6CExperimental results for a 60V-6kV DC-DC power converter are shown. Although the converter's output voltage peaks in the 0.9MHz-1MHz switching frequency range, a switching frequency of 1.25MHz is still used to achieve both a fairly high output voltage and a fast rise time. Using a 6.1 kV output voltage, 37 W of power is delivered to a 1 M resistor used as the load.

[0069] Figure 6A Thermal images of the transformer after three minutes of continuous operation of a DC-DC power converter at 6kV and 36W output are shown. More specifically, the images shown are of a 60V-6kV DC-DC power converter. The temperature of the planar PCB transformer rises slowly but steadily throughout the operation, reaching 155 degrees Celsius (C) after three minutes of continuous operation, at which point the converter is shut down to prevent damage to the transformer. In the specific experimental embodiment, an FR4 board with a rated Tg of 130 degrees Celsius was used.

[0070] Figure 6B The waveforms of the output voltage and inverter half-bridge output at converter turn-on are shown, from which the rise time from 10% to 90% is measured to be 135µs. The waveforms shown include the output voltage 660 (blue) and inverter half-bridge output 661 (yellow) at converter turn-on, with the horizontal scale at 50µs / div and the vertical scale at 1kV / div. Figure 6C The converter's 0-6kV pulse operation is shown, for example, the converter's pulse operation is shown. The steady-state output voltage is 6.08kV, and the DC-DC efficiency is 81%.

[0071] Various embodiments are provided for 60V-24kV, 60V-20kV, and 60V-35kV DC-DC converters in multi-level configurations. In such experimental embodiments, the number of stacked DC-DC converter units varies from four to six, and the performance of each configuration is measured.

[0072] Figures 7A-7D Example experimental results for another power converter according to various embodiments of this disclosure are shown. More specifically, Figures 7A-7D The output voltage waveforms of the four-stage, five-stage, and six-stage cascaded converters are shown, from which the steady-state output voltages are measured to be 23.9kV, 30.4kV, and 35.0kV, respectively. Figure 7A The pulse operation of a four-stage 60V-24kV DC-DC converter is shown. The horizontal scale is 500µs / div, and the vertical scale is 4kV / div (the voltage on the screen is scaled down to a 2:1 ratio). Figure 7BThe pulse operation of a five-stage 60V-30kV DC-DC converter is shown. The horizontal scale is 500µs / div, and the vertical scale is 5kV / div (the voltage on the screen is scaled down to a 5:1 ratio). Figure 7C The turn-on times of a six-stage 60V-35kV DC-DC converter are shown. The horizontal scale is 100µs / div, and the vertical scale is 6kV / div (the voltage on the screen is scaled down to a 3:1 ratio). Figure 7B This illustrates the pulse operation of a six-stage 60V-35kV DC-DC converter. The horizontal and vertical scales are... Figure 7C The same as in.

[0073] Figures 8A-8B Example experimental performance results of another power converter according to various embodiments of this disclosure are shown. More specifically, Figures 8A-8B The performance variation of the DC-DC converter is shown when different numbers of 6kV units are stacked, where Figure 8A The efficiency change is shown, and Figure 8B The rise time variation is shown from 10% to 90%. Efficiency tends to decrease with the number of stacked units, dropping from 82% in a single 6kV unit to 73% in a six-stage configuration. One possible reason for this efficiency decrease is that the close stacking of these multiple transformers results in a different high-frequency current distribution in the transformer windings compared to a single-stage case, which increases conduction losses on the planner PCB transformer. The converter rise time tends to increase with the number of stacked units, increasing from 135µs in a single unit to 296µs in a cascaded six-unit configuration. This increase is primarily attributed to stray capacitance between the primary and secondary windings of the transformers, which charges to half the output voltage of the DC-DC converter upon turn-on.

[0074] As previously described, the aforementioned devices can be implemented in a variety of systems or other equipment. Example systems include CT scanner gantry, ion sources (e.g., X-ray sources for medical imaging, linear accelerators, neutron generators for bomb detection, drill bit imaging for oil well logging and geological exploration), electrostatic adhesion (e.g., portable high-voltage power supplies enabling electrostatic adhesion applications such as material handling, robotic grippers, and drone landing), TWT power supplies, electrostatic filters, electrostatic sprayers (e.g., using a large electric field to ionize particles for adhesion in coating applications), electrohydrodynamic propulsion (e.g., using a large electric field to ionize and accelerate air to generate aerodynamic propulsion), high-power laser power supplies, Taser guns, particle accelerometers, plasma generators (e.g., for controlling surfaces and modifying airflow in aerodynamic applications), capacitor charging, and ozone generation.

[0075] Figure 9Examples of CT scanner gantry devices according to various embodiments are shown. The CT scanner gantry 970 includes one or more of the aforementioned devices that form part of a high-voltage generator 972. The size and weight of the CT scanner gantry using the aforementioned power conversion devices are smaller than those of other solutions, and allow for faster gantry rotation 971. Faster rotation results in a reduced radiation dose to the patient. According to various embodiments, using the CT scanner gantry 970 can result in a lower radiation dose to the patient.

[0076] Figure 10 An example traveling wave tube (TWT) radar power supply according to various embodiments is shown. The TWT radar power supply using the above-described device 1080 can have a reduced size, which allows for the use of more powerful radar systems in mobile applications, or for mounting such radars in smaller vehicles (e.g., drones, cars, etc.) that were previously too large due to the system's size and weight. Device 1080 includes a TWT 1081 and an HV power supply 1082, which includes the power converter described above.

[0077] The embodiments described herein are not limited to, for example Figures 9-10 The specific example systems and / or methods shown, as well as Appendices B and C, illustrate example systems and / or methods involving power conversion according to various specific embodiments and which may be used therein.

[0078] As described herein, various experimental embodiments are for multi-stage Class DE rectifier circuits with inductive isolation. High-frequency operation allows for fast transient response of the output voltage. The use of an input-parallel, output-series structure with an air-core PCB transformer having high DC voltage blocking capability results in a high output voltage for the DC-DC converter. Specific experimental embodiments demonstrate that a 60V to 6kV DC-DC converter can deliver 36W of power to a load at a switching frequency of 1.25MHz, and a high-gain DC-DC converter in a multi-stage configuration can deliver 35kV and 203W of power to a load while maintaining 73% efficiency and providing a pulse output with a rise time of 296µs.

[0079] This application claims the benefit of a basic provisional application entitled "Apparatuses and Methods Involving a Power Converter that includes a Multi-stage Rectifier" (Serial No. 62 / 639,865), filed March 7, 2018, and comprising three appendices, which is incorporated herein by reference in its entirety. For example, embodiments herein and / or in the provisional application (including the appendices therein) may be combined to varying degrees (including in whole). Reference may also be made to the experimental teachings and basic references provided in the basic provisional application, including the appendices that form part of the provisional application. Unless otherwise stated, the embodiments discussed in the appendices are not intended to limit in any way to the overall technical disclosure or to any part of the claimed invention.

[0080] The appendices to the basic provisional application are incorporated herein by reference in their entirety for their general and specific teaching. Appendix A, entitled “60 V-to-35 kV Input-Parallel Output-Series DC-DC Converter Using Multi-Level Class-DE Rectifiers,” provides a general and specific description of the various power converters, rectifiers, multi-level rectifier stacks, inverters, and applications shown herein. Appendix B, entitled “High-Voltage High-Gain DC-DC Converter with Inductive Isolation for Multi-Level Cascade of Class-DE Rectifiers,” provides a general and specific description of the applications of the power converters shown herein. Appendix C, entitled “High Voltage Generator,” provides a general and specific description of the uses and applications of power converters, including the high-voltage generators shown herein. These documents are incorporated herein in their entirety by referencing their teachings (including the background references cited therein, and disclosing applications that are beneficial to this disclosure), thereby relating generally and specifically to the structures, processes, methods, and uses described and shown herein.

[0081] Various boxes, modules, or other circuits can be implemented to perform one or more operations and activities described herein and / or shown in the accompanying drawings. In these contexts, a “box” (sometimes also referred to as a “logic circuit” or “module”) is one or more of these or related operations / activities performed (e.g., such as…). Figure 1 (As depicted by one or more boxes or circuit components shown). For example, in some embodiments discussed above, one or more modules are discrete logic circuits or programmable logic circuits configured and arranged to implement these operations / activities, such as... Figure 1 The circuit modules shown are illustrated. In some embodiments, such programmable circuitry is one or more computer circuits programmed to execute a set (or more) of instructions (and / or configuration data). The instructions (and / or configuration data) may be in the form of firmware or software stored in and accessible from memory (circuit). For example, the first module and the second module comprise a combination of circuitry based on CPU hardware and a set of instructions in firmware form, wherein the first module includes a first CPU hardware circuitry having a first set of instructions, and the second module includes a second CPU hardware circuitry having another set of instructions.

[0082] Some embodiments are directed to computer program products (e.g., non-volatile storage devices) that include machine or computer-readable media on which instructions are stored, which can be executed by a computer (or other electronic device) to perform these operations / activities.

[0083] Based on the foregoing discussion and illustrations, those skilled in the art will readily recognize that various modifications and changes can be made to the various embodiments without strictly adhering to the exemplary embodiments and applications shown and described herein. For example, various imaging processing circuits can be implemented as discussed herein. Furthermore, the various embodiments described herein can be combined in certain embodiments, and aspects of each embodiment can be implemented as separate embodiments. Such modifications do not depart from the true spirit and scope of the various aspects of this disclosure, including those set forth in the claims.

Claims

1. A device for power conversion, comprising: A first DC-AC inverter, the DC-AC inverter being configured to invert at least one DC input signal corresponding to an input voltage into a first AC signal; A second DC-AC inverter is configured to invert the at least one DC input signal corresponding to the input voltage into a second AC signal. A first circuit includes a first inductive isolation circuit driven in response to power from the first alternating current (AC) signal, and a first rectifier circuit that responds to the first inductive isolation circuit by outputting a first rectified signal at a first pair of output terminals. The second circuit includes a second inductive isolation circuit driven in response to power from the second AC signal, and includes a second rectifier circuit that responds to the second inductive isolation circuit by outputting a second rectified signal at a second pair of output terminals, and at least one of the first rectifier circuit and the second rectifier circuit is characterized as being limited by a rated breakdown voltage. as well as An output circuit is configured and arranged to provide a DC output voltage signal between voltage source terminals and to cascade multiple signals, including a first rectified signal and a second rectified signal, by using one of the pairs of output terminals as a supply source to one of the other pairs of output terminals. The voltage source terminals provide a voltage source that depends on the first rectified signal and the second rectified signal and is greater than the rated breakdown voltage of at least one of the first and second rectified rectifier circuits. The first inductive isolation circuit is configured to provide inductive isolation between the first DC-AC inverter and the first rectifier circuit, the second inductive isolation circuit is configured to provide inductive isolation between the second DC-AC inverter and the second rectifier circuit, and at least one of the first inductive isolation circuit and the second inductive isolation circuit is associated with another rated breakdown voltage, the other rated breakdown voltage being greater than the rated breakdown voltage of the at least one of the first rectifier circuit and the second rectifier circuit.

2. The apparatus as claimed in claim 1, characterized in that, Each of the first inductive isolation circuit and the second inductive isolation circuit includes a corresponding transformer, the transformer including a first coil arranged along a first plane and a second coil arranged along a second plane parallel to the first plane.

3. The apparatus as described in claim 2, characterized in that, The first and second coils of each respective transformer are separated by an electrically insulating material integrated as part of a printed circuit board.

4. The apparatus as claimed in claim 1, characterized in that, The at least one rectifier circuit in the first rectifier circuit and the second rectifier circuit is configured and arranged to deliver a DC output voltage signal in the associated rectified signal that is greater than twice the rated breakdown voltage of the at least one rectifier circuit in the first rectifier circuit and the second rectifier circuit.

5. The apparatus as claimed in claim 1, characterized in that, Each of the first and second inductive isolation circuits includes an air-core transformer with an associated rated breakdown voltage, the associated rated breakdown voltage being: Greater than the rated breakdown voltage of at least one of the first and second rectifier circuits, and The minimum total rated breakdown voltage of the circuits included in the first inductive isolation circuit and the second inductive isolation circuit is defined.

6. The apparatus as claimed in claim 1, characterized in that, The rated breakdown voltage is defined by a DC blocking capacitor used in the signal path of one of the first and second circuits, between the output terminal of the inductive isolation circuit and the diode in the rectifier circuit.

7. The apparatus as claimed in claim 1, characterized in that, Each of the first rectifier circuit and the second rectifier circuit includes or is configured as a Class DE rectifier.

8. The apparatus of claim 1, further comprising an additional rectifier circuit having an output cascaded with the first rectifier circuit and the second rectifier circuit, wherein each of the rectifier circuits comprises or is configured as a Class DE rectifier, isolated from the input voltage DC and rated at a voltage not less than 300 volts.

9. The apparatus of claim 1, further comprising at least one additional circuit, the at least one additional circuit including a third circuit having a third inductive isolation circuit driven in response to power from the at least one AC signal and including a third rectifier circuit that responds to the third inductive isolation circuit by outputting a third rectified signal at a third pair of output terminals; and The output circuit is further configured and arranged to provide a DC output voltage signal between voltage source terminals, and to cascade multiple signals including the first, second, and third rectified signals by coupling selected output terminals of the first, second, and third pairs of output terminals as cascaded power sources, wherein the first, second, and third voltage source terminals are arranged together to provide a voltage source that depends on the first, second, and third rectified signals and is greater than the rated breakdown voltage.

10. The apparatus as claimed in claim 1, characterized in that, Each of the first rectifier circuit and the second rectifier circuit is one of a plurality of rectifier stages connected in parallel.

11. A method for power conversion, comprising: A first AC signal is provided by a first DC-AC inverter and a second AC signal is provided by a second DC-AC inverter; A first circuit and a second circuit are used in parallel. The first circuit includes a first inductive isolation circuit to provide inductive isolation and is driven in response to power from a first AC signal. The second circuit includes a second inductive isolation circuit to provide inductive isolation and is driven in response to power from a second AC signal. Each of the first circuit and the second circuit includes a rectifier circuit to rectify in response to the inductive isolation by outputting a rectified signal at an associated pair of output terminals. The rectification associated with at least one of the first circuit and the second circuit is associated with a circuit characterized as being limited by a rated breakdown voltage. as well as A DC output voltage signal is provided between voltage source terminals by cascading multiple signals, including the rectified signal, wherein the DC output voltage signal depends on the second rectified signal and is greater than the rated breakdown voltage. The first inductive isolation circuit is configured to provide inductive isolation between the first DC-AC inverter and the first rectifier circuit of the first circuit, the second inductive isolation circuit is configured to provide inductive isolation between the second DC-AC inverter and the second rectifier circuit of the second circuit, and at least one of the first inductive isolation circuit and the second inductive isolation circuit is associated with another rated breakdown voltage, the other rated breakdown voltage being greater than the rated breakdown voltage.

12. The method as described in claim 11, characterized in that, At least one of the first circuit and the second circuit includes a planar transformer.

13. A DC power source for providing a direct current (DC) voltage, the DC power source comprising: A first circuit, the first circuit including a first inductive isolation circuit driven in response to power from a first AC signal, and a first rectifier circuit in response to the first inductive isolation circuit by outputting a first rectified signal at a first pair of output terminals; The second circuit includes a second inductive isolation circuit driven in response to power from a second AC signal, and includes a second rectifier circuit that responds to the second inductive isolation circuit by outputting a second rectified signal at a second pair of output terminals, and at least one of the first rectifier circuit and the second rectifier circuit is characterized as being limited by a rated breakdown voltage. as well as An output circuit is configured and arranged to provide a DC output voltage signal between voltage source terminals and to cascade multiple signals, including a first rectified signal and a second rectified signal, by using one of the pairs of output terminals as a supply source to one of the other pairs of output terminals. The voltage source terminals provide a voltage source that depends on the first rectified signal and the second rectified signal and is greater than the rated breakdown voltage of at least one of the first and second rectified rectifier circuits. The first inductive isolation circuit is configured to provide inductive isolation before the first rectifier circuit, the second inductive isolation circuit is configured to provide inductive isolation before the second rectifier circuit, and at least one of the first inductive isolation circuit and the second inductive isolation circuit is associated with another rated breakdown voltage, the other rated breakdown voltage being greater than the rated breakdown voltage of the at least one of the first rectifier circuit and the second rectifier circuit.

14. The DC power source of claim 13, further comprising a front-end driver circuit configured and arranged to provide the first AC signal to the first inductive isolation circuit and the second AC signal to the second inductive isolation circuit.

15. The DC power source as described in claim 14, characterized in that, The front-end driver circuit includes one or more DC-AC inverter circuits configured and arranged to invert at least one DC input signal into the first AC signal and the second AC signal.

16. The DC power source as described in claim 14, characterized in that, The front-end driver circuit includes one or more AC-AC inverter circuits configured and arranged to invert at least one AC input signal at a first frequency into the first and second AC signals corresponding to a second frequency, and to drive the first inductor isolation circuit via the first AC signal and the second inductor isolation circuit via the second AC signal at the second frequency.

17. The DC power source as described in claim 13, characterized in that, Each of the first and second inductive isolation circuits includes an air-core transformer having an additional rated breakdown voltage associated with the material between the windings of the air-core transformer, and the additional rated breakdown voltage being greater than the rated breakdown voltage of at least one of the first and second rectifier circuits.

18. The DC power source as described in claim 13, characterized in that, The at least one rectifier circuit in the first rectifier circuit and the second rectifier circuit includes a DC blocking capacitor used in the signal path of one of the first circuit and the second circuit, between the output terminal of the inductive isolation circuit and the diode in the rectifier circuit, the DC blocking capacitor being characterized as being limited by the rated breakdown voltage.

19. The DC power source of claim 13, further comprising a plurality of circuits, the plurality of circuits including the first circuit and the second circuit arranged in cascade between voltage rails, and at least one of the first rectifier circuit and the second rectifier circuit being located closest to one of the voltage rails.

20. The DC power source as described in claim 13, characterized in that, The input terminals of the first rectifier circuit and the second rectifier circuit are connected in parallel via the output circuit, and the output terminals of the pairs of output terminals are connected in series.

21. The DC power source as described in claim 13, characterized in that, At least one of the first inductive isolation circuit and the second inductive isolation circuit includes a corresponding transformer, the transformer comprising at least two coils separated by an electrically insulating material integrated as part of a printed circuit board.

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