Parallel connection method for interleaved power converters

Abstract

Examples of this disclosure include a UPS comprising an output to be coupled to a load, a first converter branch providing a first voltage to the output and including at least one of a first relay or a fuse, a second converter branch connected in parallel with the first converter branch, including at least one of a second relay or a fuse and configured to provide a second voltage to the output that is out of phase with the first converter branch providing the first voltage signal, current sensors coupled to the first and second converter branches respectively and configured to provide a first signal indicating current in the first converter branch and a second signal indicating current in the second converter branch respectively, and at least one controller receiving the signal, determining the current difference between the converter branches based on the signal, and reducing the current difference.

Description

Technical Field

[0001] At least one example according to this disclosure generally relates to a multiphase power converter. Background Technology

[0002] Power devices such as uninterruptible power supplies (UPS) can be used to provide regulated, uninterrupted power to sensitive and / or critical loads such as computer systems and other data processing systems. A UPS may include one or more power converters, such as DC / DC converters, DC / AC converters, AC / DC converters, etc. Some power converters may include multiple interleaved branches, each carrying a portion of the power converted by the power converter. Summary of the Invention

[0003] According to at least one aspect of this disclosure, an uninterruptible power supply (UPS) is provided, comprising: a first input configured to be coupled to a main power supply; a second input configured to be coupled to a backup power supply; an output configured to be coupled to a load; a first converter branch configured to provide a first voltage signal to the output, wherein the first converter branch includes at least one of a first relay or a first fuse; a second converter branch configured to provide a second voltage signal to the output and configured to be coupled in parallel with the first converter branch, wherein the second converter branch provides a second voltage signal out of phase with the first converter branch providing the first voltage signal, and wherein the second converter branch includes at least one of a second relay or a second fuse; a first current sensor coupled to the first converter branch and configured to provide a first current sensing signal indicating a first current in the first converter branch; a second current sensor coupled to the second converter branch and configured to provide a second current sensing signal indicating a second current in the second converter branch; and at least one controller configured to receive the first current sensing signal and the second current sensing signal, determine a current difference between the first converter branch and the second converter branch based on the first current sensing signal and the second current sensing signal, and reduce the current difference.

[0004] In some examples, a first converter branch includes a first filter, and a second converter branch includes a second filter. In various examples, at least one of a first relay or a first fuse is coupled between the first filter and the output, and at least one of a second relay or a second fuse is coupled between the second filter and the output. In at least one example, the first filter includes at least one first capacitor, and the second filter includes at least one second capacitor. In some examples, the first filter includes at least one first inductor coupled to at least one first capacitor, and the second filter includes at least one second inductor coupled to at least one second capacitor. In various examples, the first filter includes a first choke, and the second filter includes a second choke, the first choke being inductively coupled to the second choke.

[0005] In at least one example, a first choke is configured to induce a first induced current in a second choke in response to a first ripple current flowing through a first converter branch, and a second choke is configured to induce a second induced current in the first choke in response to a second ripple current flowing through a second converter branch. In some examples, at least one of a first relay or a first fuse includes both a first relay and a first fuse. In various examples, at least one of a second relay or a second fuse includes both a second relay and a second fuse. In at least one example, a first converter branch includes at least one first power conversion switch having a first switch input and a first switch output, and a second converter branch includes at least one second power conversion switch having a second switch input and a second switch output.

[0006] In some examples, at least one of the first relays or first fuses is coupled between a first switch input and at least one of the first input or second input, and at least one of the second relays or second fuses is coupled between a second switch input and at least one of the first input or second input. In various examples, at least one of the first relays or first fuses is coupled between a first switch output and an output, and at least one of the second relays or second fuses is coupled between a second switch output and an output.

[0007] According to an aspect of this disclosure, a method of assembling an uninterruptible power supply (UPS) is provided, the method comprising providing a first converter branch having at least one of a first relay or a first fuse; providing a second converter branch having at least one of a second relay or a second fuse; providing a first current sensor configured to provide a first current sensing signal indicating a first current in the first converter branch; providing a second current sensor configured to provide a second current sensing signal indicating a second current in the second converter branch; providing at least one controller; coupling the first converter branch and the second converter branch in parallel; coupling the first current sensor to the first converter branch; coupling the second current sensor to the second converter branch; and coupling the at least one controller to the first converter branch and the second converter branch to receive the first current sensing signal and the second current sensing signal, determining a current difference between the first converter branch and the second converter branch based on the first current sensing signal and the second current sensing signal, and reducing the current difference between the first converter branch and the second converter branch.

[0008] In some examples, the uninterruptible power supply includes an output, and the method further includes providing a first filter in a first converter branch; providing a second filter in a second converter branch; coupling at least one of a first relay or a first fuse between the first filter and the output; and coupling at least one of a second relay or a second fuse between the second filter and the output. In various examples, providing the first filter includes providing at least one first capacitor, and providing the second filter includes providing at least one second capacitor, the method further including coupling at least one first capacitor to at least one of the first relay or the first fuse, and coupling at least one second capacitor to at least one of the second relay or the second fuse.

[0009] In at least one example, providing a first filter includes providing at least one first inductor, and providing a second filter includes providing at least one second inductor. The method further includes coupling at least one first inductor to at least one first capacitor and coupling at least one second inductor to at least one second capacitor. In some examples, the method includes providing a first choke and a second choke, coupling the first choke to at least one of a first relay or a first fuse, coupling the second choke to at least one of a second relay or a second fuse, and inductively coupling the first choke to the second choke. In various examples, providing a first converter branch having at least one of a first relay or a first fuse includes providing a first relay and a first fuse. In at least one example, providing a first converter branch having at least one of a second relay or a second fuse includes providing a second relay and a second fuse.

[0010] According to an aspect of this disclosure, a non-transitory computer-readable medium on which a sequence of computer-executable instructions is stored is provided for controlling an uninterruptible power supply (UPS), the UPS including at least one input, an output, a first converter branch including at least one of a first current sensor and a first relay or a first fuse, and a second converter branch configured to be coupled in parallel with the first converter branch, the second converter branch including at least one of a second current sensor and a second relay or a second fuse, the sequence of computer-executable instructions including instructions instructing at least one processor to control the first converter branch via the first relay or the first current sensor. At least one of the fuses provides a first voltage signal to the output; controls a second converter branch to provide a second voltage signal to the output via at least one of a second relay or a second fuse, wherein the second converter branch provides a second voltage signal out of phase with the first converter branch that provides the first voltage signal; receives a first current sensing signal indicating a first current in the first converter branch from a first current sensor; receives a second current sensing signal indicating a second current in the second converter branch from a second current sensor; determines the current difference between the first converter branch and the second converter branch based on the first current sensing signal and the second current sensing signal; and reduces the current difference between the first converter branch and the second converter branch. Attached Figure Description

[0011] At least one embodiment will now be discussed with reference to the accompanying drawings, which are not intended to be drawn to scale. The drawings are included to provide illustration and further understanding of the aspects and embodiments, and are incorporated in and form part of this specification, but are not intended to be a definition of limitation for any particular embodiment. The drawings, together with the remainder of the specification, serve to explain the principles and operation of the described and claimed aspects and embodiments. In the drawings, each identical or substantially identical component shown in the various figures is represented by the same numerals. For clarity, not every component may be labeled in every figure. In the drawings:

[0012] Figure 1 A block diagram of an uninterruptible power supply (UPS) based on an example is shown;

[0013] Figure 2 A block diagram of a power converter based on an example is shown;

[0014] Figure 3 A block diagram of a power converter according to another example is shown;

[0015] Figure 4 The operation based on the example is shown. Figure 3 The process of a power converter;

[0016] Figure 5 The example is shown. Figure 3 A schematic diagram of the power converter;

[0017] Figure 6 A block diagram of a power converter according to another example is shown;

[0018] Figure 7 The example is shown. Figure 6 A schematic diagram of the power converter; and

[0019] Figure 8 An example based on another example is shown. Figure 6 A schematic diagram of the power converter. Detailed Implementation

[0020] The examples of methods and systems discussed herein are not limited in application to the details of construction and component arrangement set forth in the following description or shown in the accompanying drawings. These methods and systems can be implemented in other embodiments and can be practiced or performed in various ways. The examples of specific implementations provided herein are for illustrative purposes only and are not intended to be limiting. In particular, actions, components, elements, and features discussed in conjunction with any one or more examples are not intended to exclude similar roles in any other examples.

[0021] Furthermore, the wording and terminology used herein are for descriptive purposes and should not be considered limiting. Any reference to examples, embodiments, components, elements, or actions of systems and methods mentioned herein in the singular may also cover embodiments that include multiple embodiments, and any reference to any embodiment, component, element, or action mentioned herein in the plural may also cover embodiments that include only the singular. References in either the singular or plural form are not intended to limit the currently disclosed systems or methods, their components, actions, or elements. The terms "including," "comprising," "having," "comprise," "involving," and variations thereof, as used herein, mean to include the items listed thereafter and their equivalents, as well as additional items.

[0022] References to “or” can be interpreted as inclusive, such that any term described using “or” can refer to a single, more than one, or any of the terms described. Furthermore, in the event of inconsistencies in terminology between this document and documents incorporated herein by reference, the terminology used in the incorporated document is supplementary to this document; for irreconcilable differences, the terminology used in this document shall prevail.

[0023] Power devices are configured to provide output power to a load. For example, an uninterruptible power supply (UPS) is a power device configured to provide regulated, uninterrupted power to a load. Single-phase UPSs provide single-phase power, while multi-phase UPSs provide multi-phase power. For example, a three-phase UPS provides three-phase power to a load.

[0024] Power devices may include one or more power converters. Power converters include devices that convert power from one state to another, such as rectifiers, inverters, power factor correction (PFC) circuits, DC / DC converters, etc. A power converter may include multiple converter branches, each configured to convert a corresponding portion of the input power. In some power converters, the branches may be coupled in parallel and interleaved. Each interleaved branch converts a corresponding portion of the power supplied by the power converter. Interleaving can advantageously reduce ripple current in the power converter.

[0025] Interleaved multi-branch converters may include a common component. This common component is shared across each converter branch, such that power supplied by each converter branch is provided to the common component. Conversely, individual components are components within or coupled to a single branch of the multi-branch converter. In some examples, an individual component receives power only from the converter branch in which it is located, rather than from every branch in the converter.

[0026] In some interleaved multi-branch converters, the common component may include at least one common filter capacitor, filter inductor, relay, and / or fuse. Because the common component receives current from each of the multiple branches, it can have a high current rating to maintain a high total current supplied to it.

[0027] Such high current ratings can present practical manufacturing challenges. For example, it may be difficult or impossible to obtain PCB mounting components with sufficiently high current ratings. Furthermore, regulatory requirements may be difficult or impossible to meet. For instance, Underwriters Laboratories (UL) requirements may not accept hard parallel connections of common components such as feedback relays and fuses, as a failure in one component could cause voltage spikes or high currents in non-faulty components. Additionally, common fuses may have significant knockout energy due to the high common current they conduct. Such significant knockout energy can adversely damage adjacent components, making troubleshooting difficult and complicating live component replacement.

[0028] Examples of this disclosure include multi-branch converters having multiple parallel and / or interleaved branches. Each converter branch may include one or more individual components. These individual components may include components implemented as common components in other topologies. These individual components may include, for example, one or more fuses, relays, filters, current sensors, etc. In some examples, each converter branch includes a current sensor configured to provide a current-sensing signal indicative of the current in the respective converter branch to at least one controller. The at least one controller may determine the current difference between the parallel converter branches and reduce the current difference to balance the converter branches. For example, the at least one controller may control one or more power converters in the respective converter branch to modulate the current in the one or more converter branches. Thus, examples of this disclosure include multi-branch power converters with increased power density and reduced size of converter components (such as passive components).

[0029] Current power conversion systems, such as power converters in UPS systems, can include interleaved converter branches, with one or more common components coupled to all interleaved converter branches. Such power conversion systems can operate inefficiently because the common component conducts the entire converter current, which may require very large components that are difficult to obtain commercially, reducing power density, significantly impacting clean energy, and complicating efforts to obtain UL certification. This is a technical problem.

[0030] An exemplary embodiment of a power conversion system includes an uninterruptible power supply (UPS) having a first input configured to be coupled to a main power supply; a second input configured to be coupled to a backup power supply; an output configured to be coupled to a load; a first converter branch configured to provide a first voltage signal to the output, wherein the first converter branch includes at least one of a first relay or a first fuse; and a second converter branch configured to provide a second voltage signal to the output and configured to be coupled in parallel with the first converter branch, wherein the second converter branch provides a second voltage signal out of phase with the first converter branch providing the first voltage signal. The second converter branch includes at least one of a second relay or a second fuse; a first current sensor coupled to the first converter branch and configured to provide a first current sensing signal indicating a first current in the first converter branch; a second current sensor coupled to the second converter branch and configured to provide a second current sensing signal indicating a second current in the second converter branch; and at least one controller configured to receive the first current sensing signal and the second current sensing signal, determine a current difference between the first converter branch and the second converter branch based on the first current sensing signal and the second current sensing signal, and reduce the current difference.

[0031] At least this combination of the aforementioned features includes a power conversion system that serves as a technical solution to the aforementioned technical problem. This technical solution is unconventional and non-traditional. It is a practical application of power conversion system design that solves the aforementioned technical problem and, at least by reducing the current conducted in the converter components, constitutes an improvement in the field of power converter technology.

[0032] The example power converter can be implemented in any of many types of power devices. For illustrative purposes, an example of a power converter implemented in a UPS is given. This example power converter can be implemented in any of many types of UPS, such as offline UPS, online UPS, line-interactive UPS, single-phase UPS, multi-phase UPS, etc. Therefore, it should be understood that the example power converter is not limited to implementation in a UPS, nor is it limited to a specific UPS topology.

[0033] Figure 1This is a block diagram based on the example UPS 100. UPS 100 includes an input 102, an AC / DC converter 104, one or more DC buses 106, a DC / DC converter 108, an energy storage device interface 110, at least one controller 112 (“Controller 112”), a DC / AC inverter 114, an output 116, a memory and / or storage device 118, and one or more communication interfaces 120 (“Communication Interface 120”) that can be communicatively coupled to one or more external systems 122 (“External System 122”). Input 102 is coupled to the AC / DC converter 104 and an AC power source (not shown), such as an AC mains power supply. AC / DC converter 104 is coupled to input 102 and one or more DC buses 106, and communicatively coupled to controller 112. One or more DC buses 106 are coupled to AC / DC converter 104, DC / DC converter 108, and DC / AC inverter 114, and communicatively coupled to controller 112. DC / DC converter 108 is coupled to one or more DC buses 106 and energy storage device interface 110, and communicatively coupled to controller 112. Energy storage device interface 110 is coupled to DC / DC converter 108 and configured to couple to at least one battery 124 and / or another energy storage device. In some examples, UPS 100 may include one or more energy storage devices, such as battery 124. DC / AC inverter 114 is coupled to one or more DC buses 106 and output 116, and communicatively coupled to controller 112. Output 116 is coupled to DC / AC inverter 114 and an external load (not shown). Controller 112 is communicatively coupled to AC / DC converter 104, one or more DC buses 106, DC / DC converter 108, energy storage device interface 110, DC / AC inverter 114, memory and / or storage device 118, and communication interface 120.

[0034] Input 102 is configured to couple to an AC mains power supply and receive input AC power having an input voltage level. UPS 100 is configured to operate in different operating modes based on the input voltage of the AC power supplied to input 102. Controller 112 can determine the operating mode of UPS 100 based on whether the input voltage of the AC power is acceptable. Controller 112 may include or be coupled to one or more sensors configured to sense parameters of the input voltage. For example, controller 112 may include or be coupled to one or more sensors configured to sense the voltage level of the AC power received at input 102, one or more current sensors in each of components 104, 108, and 114, etc.

[0035] When the AC power supplied to input 102 is acceptable (e.g., by having parameters that meet specified values, such as input voltage values, such as falling within an acceptable range of input voltage values), controller 112 controls the components of UPS 100 to operate in normal operating mode. In normal operating mode, the AC power received at input 102 is supplied to AC / DC converter 104. AC / DC converter 104 converts the AC power into DC power and supplies the DC power to one or more DC buses 106. One or more DC buses 106 distribute the DC power to DC / DC converter 108 and DC / AC inverter 114. DC / DC converter 108 converts the received DC power and supplies the converted DC power to energy storage device interface 110. Energy storage device interface 110 receives the converted DC power and supplies the converted DC power to battery 124 to charge battery 124. DC / AC inverter 114 receives DC power from one or more DC buses 106, converts the DC power into regulated AC power, and supplies the regulated AC power to output 116 to deliver to the load.

[0036] When the AC power supplied to input 102 from the AC mains is unacceptable (e.g., by parameters that do not meet specified values, such as input voltage values, or by falling outside the acceptable range of input voltage values), controller 112 controls components of UPS 100 to operate in standby mode. In standby mode, DC power is discharged from battery 124 to energy storage device interface 110, and energy storage device interface 110 supplies the discharged DC power to DC / DC converter 108. DC / DC converter 108 converts the received DC power and distributes the DC power among one or more DC buses 106. For example, DC / DC converter 108 may distribute power evenly among one or more DC buses 106. One or more DC buses 106 supply the received power to DC / AC inverter 114. DC / AC inverter 114 receives DC power from one or more DC buses 106, converts the DC power into regulated AC power, and supplies the regulated AC power to output 116.

[0037] Controller 112 can control various aspects of UPS 100, supplementing or replacing one or more of the aforementioned actions. For example, controller 112 can control and / or communicate with one or more components or devices of AC / DC converter 104, DC / DC converter 108, and / or DC / AC inverter 114, such as switches, fuses, relays, current sensors, etc. Controller 112 can store information in and / or retrieve information from memory and / or storage device 118. For example, controller 112 can store information indicating sensed parameters (e.g., input voltage value of AC power received at input 102, converter current value of current in components 104, 108, and / or 114, etc.) in memory and / or storage device 118. Controller 112 can also receive information from or provide information to communication interface 120. Communication interface 120 may include one or more communication interfaces, including, for example, user interfaces (such as displays, touchscreens, keyboards, mice, trackpads, dial pads, buttons, switches, sliders, light-emitting components such as light-emitting diodes, sound-emitting components such as speakers, buzzers, etc. configured to output sound within and / or outside the frequency range audible to humans), wired communication interfaces (such as wired ports), wireless communication interfaces (such as antennas), etc., configured to exchange information with one or more systems (such as external system 122) or other entities (such as humans). External system 122 may include any devices, components, modules, etc., outside of UPS 100, such as servers, databases, laptops, desktop computers, tablets, smartphones, central controllers or data aggregation systems, other UPS systems, etc.

[0038] As described above, power converters, such as AC / DC converter 104, DC / DC converter 108, and / or DC / AC inverter 114, can include multiple converter branches. These multiple converter branches can be interleaved. Interleaving can advantageously reduce ripple current in the respective power converters. Regarding... Figure 2 Example power converters are provided, which can be examples of any of converters 104, 108, and / or 114. For illustrative purposes, a specific example of DC / AC inverter 114 may be provided.

[0039] Figure 2 A block diagram of a power converter 200 according to an example is shown. The power converter 200 can be as described above (reference provided). Figure 1Examples of aspects of the described DC / AC inverter 114. It should be understood that one or more components of the DC / AC inverter 114 may be omitted for clarity. The power converter 200 is an example of an interleaved power converter with two interleaved converter branches. It should be understood that in some examples, the power converter (such as the DC / AC inverter 114) may include more than two interleaved converter branches. Therefore, the description of the power converter 200 with two converter branches is not intended as a limitation and is provided merely for illustrative purposes.

[0040] The power converter 200 includes an input 202, an output 204, a first converter branch 206, a second converter branch 208, and a common output component 210. The first converter branch 206 includes at least one converter switch 212 (“first converter switch 212”) and at least one first branch output component 214 (“first output component 214”). The second converter branch 208 includes at least one converter switch 216 (“second converter switch 216”) and at least one second branch output component 218 (“second output component 218”).

[0041] Input 202 is coupled to a first converter switch 212 and a second converter switch 216. In some examples, input 202 may also be coupled to a power source (not shown). For example, in the case where the power converter 200 is a DC / AC inverter 114, input 202 may be coupled to a DC bus 106. The first converter switch 212 is coupled to input 202 at its switch input, to a first output component 214 at its switch output, and communicatively coupled to the controller 112. The first output component 214 is coupled to the first converter switch 212 at a first connection and to a common output component 210 at a second connection. In some examples, one or more first output components 214 are communicatively coupled to the controller 112. The first converter branch 206 is coupled in parallel with the second converter branch 208.

[0042] The second converter switch 216 is coupled to input 202 at its switch input, to a second output component 218 at its switch output, and communicatively coupled to controller 112. The second output component 218 is coupled to the second converter switch 216 at a first connection and to a common output component 210 at a second connection. In some examples, one or more second output components 218 are communicatively coupled to controller 112. The common output component 210 is coupled to the first output component 214 and the second output component 218 at a first connection and to output 204 at a second connection. Output 204 is coupled to the common output component 210 and is configured to be coupled to a load. For example, in the case where the power converter 200 is an example of a DC / AC converter 114, output 204 may be coupled to output 116.

[0043] Therefore, power converter 200 includes output components in each respective branch (e.g., first output component 214 and second output component 218), and a common output component (e.g., common output component 210) shared by both converter branches 206 and 208. In one example, output components 214 and 218 may each include a filter choke, and common output component 210 may include one or more filter components (e.g., one or more capacitors and / or inductors), relays, fuses, etc. Because the power through common output component 210 is a combination of the power from converter branches 206 and 208, the current through common output component 210 may be greater than the current through any one of converter branches 206 and 208. Therefore, common output component 210 may require a higher rated current than the output components 214 and 218 require, at least because common output component 210 receives a higher current than each of output components 214 and 218 when both output components 214 and 218 simultaneously supply current to common output component 210.

[0044] As mentioned above, in addition to the other disadvantages discussed above, subjecting certain components to high currents may disadvantageously require large components that are difficult or impossible to mount on a PCB. For example, common output component 210 may disadvantageously require large components such as relays, fuses, filters, etc. Conversely, output components 214, 218 may not be so large, at least because output components 214, 218 conduct approximately half the current conducted by common output component 210. Therefore, in some examples, one or more common output components 210 can be removed and instead implemented in output components 214, 218, enabling a reduction in component size. Regarding Figure 3 An example is provided.

[0045] Figure 3A block diagram of a power converter 300 according to another example is shown. The power converter 300 may be as described above (reference provided). Figure 1 Examples of aspects of the described DC / AC inverter 114. It should be understood that one or more components of the DC / AC inverter 114 may be omitted for clarity. The power converter 300 is another example of an interleaved power converter with two interleaved converter branches. It should be understood that in some examples, the power converter (such as the DC / AC inverter 114) may include more than two interleaved converter branches. Therefore, the description of the power converter 300 with two converter branches is not intended as a limitation and is provided merely for illustrative purposes.

[0046] The power converter 300 includes an input 302, an output 304, a first converter branch 306, and a second converter branch 308. The first converter branch 306 includes at least one first converter switch 310 (“first converter switch 310”) and at least one first branch output component 312 (“first output component 312”). The second converter branch 308 includes at least one second converter switch 314 (“second converter switch 314”) and at least one second branch output component 316 (“second output component 316”).

[0047] Input 302 is coupled to the first converter switch 310 and the second converter switch 314. In some examples, input 302 may also be coupled to a power source (not shown). For example, in the case where the power converter 300 is a DC / AC inverter 114, input 302 may be coupled to the power source mentioned above. Figure 1 The DC bus 106 is discussed. As discussed in more detail below, input 302 may include several input connections, each configured to couple to a corresponding DC bus of DC bus 106. A first converter switch 310 is coupled to input 302 at a switch input, coupled to a first output component 312 at a switch output, and communicatively coupled to controller 112. The first output component 312 is coupled to the first converter switch 310 at a first connection and coupled to output 304 at a second connection. In some examples, one or more first output components 312 are communicatively coupled to controller 112. The first converter branch 306 is coupled in parallel with the second converter branch 308.

[0048] The second converter switch 314 is coupled to input 302 at its switch input, to a second output component 316 at its switch output, and communicatively coupled to controller 112. The second output component 316 is coupled to the second converter switch 314 at a first connection and to output 304 at a second connection. In some examples, one or more second output components 316 are communicatively coupled to controller 112. Output 304 is coupled to both the first output component 312 and the second output component 316 at a first connection and is configured to be coupled to a load. For example, in the case where the power converter 300 is an example of a DC / AC inverter 114, output 304 may be coupled to output 116.

[0049] Figure 4 A process 400 for operating a power converter, such as power converter 300, is illustrated according to an example. In various examples, at least a portion of process 400 may be executed by controller 112.

[0050] At action 402, process 400 begins.

[0051] At operation 404, input power is received at input 302. For example, the input power may be received by the DC / AC inverter 114 via the DC bus 106 from a power source coupled to input 102 and / or from battery 124.

[0052] At action 406, controller 112 controls the first converter branch 306 and / or the second converter branch 308 to draw power from input 302. For example, controller 112 may control the first converter switch 310 and / or the second converter switch 314 to draw power from input 302. In some examples, controller 112 may control the first converter switch 310 to draw power from input 302 in a manner 180° out of phase with the second converter switch 314. That is, the control signal provided to the second converter switch 314 may be substantially similar to or the same as the control signal provided to the first converter switch 310, but with a 180° phase shift. In some examples, controller 112 may phase-shift the control signal provided to a multi-branch converter based on multiple branches. For example, the phase shift may be equal to φ = 360° / n, where φ is the phase shift and n is the number of branches in the multi-branch converter. In other examples, controller 112 may implement other methods for determining the phase shift. For example, controller 112 can control the first converter switch 310 to draw power from input 302 in a manner that is out of phase with the second converter switch 314 by a degree other than 180°.

[0053] Converter switches 310 and 314 can be implemented according to any of various known converter topologies, and controller 112 can control converter switches 310 and 314 according to a known control scheme corresponding to a known converter topology. As described below, controller 112 can control converter branches 306 and 308 to draw balanced power from input 302, thereby minimizing the current difference between converter branches 306 and 308.

[0054] At action 408, controller 112 controls the first converter switch 310 and / or the second converter switch 314 to provide output power to output 304 via the first output component 312 and / or the second output component 316, respectively. For example, controller 112 may control converter switches 310, 314 to provide converted output power to output components 312, 316 via the respective switch outputs. The converted output power may include converting DC power received at input 302 into AC power for output at output 304. As discussed in more detail below, output components 312, 316 may include one or more filtering components configured to filter the output power. Output components 312, 316 may also include one or more relays and / or fuses. In various examples, output components 312, 316 provide power to output 304 from converter switches 310, 314, wherein, for example, the relay(s) are closed and conductive, and the fuse(s) are conductive (i.e., not "blown"). As discussed in more detail below, output components 312, 316 may include inductively coupled chokes configured to share current between branches 306, 308, such as by sharing ripple current between branches 306, 308.

[0055] As discussed above regarding action 406, controller 112 can control the first converter switch 310 to draw power from input 302 in a manner 180° out of phase with the second converter switch 314. Therefore, controller 112 can control the first converter switch 310 such that the voltage signal supplied to output 304 by the first converter switch 310 (and thus the first converter branch 306) is out of phase with the voltage signal supplied to output 304 by the second converter switch 314 (and thus the second converter branch 308).

[0056] At action 410, controller 112 receives a first current sensing signal from first converter branch 306 and a second current sensing signal from second converter branch 308. In various examples, first output component 312 includes at least one first current sensor (not shown), such as a current transformer (CT), and second output component 316 includes at least one second current sensor, such as a CT (not shown). At least one first current sensor can measure the current through first converter branch 306 and provide a first current sensing signal to controller 112, and at least one second current sensor can measure the current through second converter branch 308 and provide a second current sensing signal to controller 112. In some examples, the sampling frequencies and / or periods of at least one first current sensor and at least one second current sensor are aligned or normalized such that the first current sensing signal and the second current sensing signal are aligned.

[0057] At action 412, controller 112 determines the current difference between converter branches 306, 308. In some examples, the current difference is an instantaneous current difference. In other examples, the current difference is determined over a period of time, such as the full switching cycle of the signals provided to converter switches 310, 314. Controller 112 can be configured to minimize the current difference such that the currents through converter branches 306, 308 are balanced (e.g., instantaneously or over a period of time).

[0058] At action 414, controller 112 reduces the current difference determined at action 410. Reducing the current difference may include increasing the power draw of one of converter branches 306, 308 and / or decreasing the power draw of the other of converter branches 306, 308. For example, if the current in the first converter branch 306 exceeds the current in the second converter branch 308, controller 112 may reduce the current difference by controlling the first converter switch 310 to draw less power from input 302 and / or by controlling the second converter switch 314 to draw more power from input 302. Process 400 then returns to action 404.

[0059] Therefore, the power converter 300 is configured to receive input power at input 302, convert the input power using at least converter switches 310, 314, and provide the converted output power to output 304. Regarding Figure 5 A schematic diagram of an example power converter 300 is shown.

[0060] Figure 5 A schematic diagram of a power converter 300 according to an example is shown. Figure 5The power converter 300 includes a first input 302a and a second input 302b (collectively referred to as input 302), an output 304, a first converter branch 306 having a first converter switch 310 and a first output component 312, and a second converter branch 308 having a second converter switch 314 and a second output component 316. The first converter switch 310 includes a first converter switch 500 and a second converter switch 502. The second converter switch 314 includes a third converter switch 504 and a fourth converter switch 506.

[0061] The first output component 312 includes a first inductor 508, a first capacitor 510, a second inductor 512 (inductors 508, 512 and the first capacitor 510 are collectively referred to as the "first filter"), a first relay 514, and a first fuse 516. The second output component 316 includes a third inductor 518, a second capacitor 520, a fourth inductor 522 (inductors 518, 522 and the second capacitor 520 are collectively referred to as the "second filter"), a second relay 524, and a second fuse 526. In some examples, each of the first output component 312 and the second output component 316 includes one or more current sensors (e.g., CTs) (not shown) configured to measure the corresponding current through the converter branches 306, 308 and send a corresponding current sensing signal to the controller 112. In various examples, each of the second inductor 512 and the fourth inductor 522 may be referred to as a "choke".

[0062] The first input 302a is coupled to the first converter switch 500 and the third converter switch 504, and is configured to be coupled to a power source or its medium, such as by coupling to the DC bus 106. For example, the first input 302a may be coupled to a positive voltage DC bus or another type of bus of the DC bus 106. The second input 302b is coupled to the second converter switch 502 and the fourth converter switch 506, and is configured to be coupled to a power source or its medium, such as by coupling to the DC bus 106. For example, the second input 302b may be coupled to a negative voltage, neutral, common, or other type of DC bus of the DC bus 106.

[0063] The first converter switch 500 is coupled to the first input 302a at the first connection, to the second converter switch 502 and the first inductor 508 at the second connection, and communicatively coupled to the controller 112 at the control connection. The second converter switch 502 is coupled to the first converter switch 500 and the first inductor 508 at the first connection, to the second input 302b at the second connection, and communicatively coupled to the controller 112 at the control connection. The third converter switch 504 is coupled to the first input 302a at the first connection, to the fourth converter switch 506 and the third inductor 518 at the second connection, and communicatively coupled to the controller 112 at the control connection. The fourth converter switch 506 is coupled to the third converter switch 504 and the third inductor 518 at the first connection, to the second input 302b at the second connection, and communicatively coupled to the controller 112 at the control connection.

[0064] A first inductor 508 is coupled at a first connection to a first converter switch 500 and a second converter switch 502, and at a second connection to a first capacitor 510 and a second inductor 512. A first capacitor 510 is coupled at a first connection to the first inductor 508 and the second inductor 512, and at a second connection to a second reference node 530. A second inductor 512 is coupled at a first connection to the first inductor 508 and the first capacitor 510, and at a second connection to a first relay 514. In some examples, the second inductor 512 is inductively coupled to a fourth inductor 522. For example, the second inductor 512 may be inductively coupled to the fourth inductor 522 to allow ripple current to flow between converter branches 306, 308 to reduce ripple current in capacitors 510, 520 of the power converter 300. In some examples, the first inductor 508 and the third inductor 518 may also be at least partially inductively coupled to each other to reduce ripple current in each converter branch. For example, the ripple current in the first inductor 508 can induce an induced current in the third inductor 518, and the ripple current in the third inductor 518 can induce an induced current in the first inductor 508. The first relay 514 is coupled to the second inductor 512 at a first connection, to the first fuse 516 at a second connection, and communicatively coupled to the controller 112. The first fuse 516 is coupled to the first relay 514 at a first connection and to the output 304 at a second connection.

[0065] The third inductor 518 is coupled at a first connection to the third converter switch 504 and the fourth converter switch 506, and at a second connection to the second capacitor 520 and the fourth inductor 522. The second capacitor 520 is coupled at a first connection to the third inductor 518 and the fourth inductor 522, and at a second connection to the second reference node 530. The fourth inductor 522 is coupled at a first connection to the third inductor 518 and the second capacitor 520, and at a second connection to the second relay 524. The second relay 524 is coupled at a first connection to the fourth inductor 522, at a second connection to the second fuse 526, and communicatively coupled to the controller 112. The second fuse 526 is coupled at a first connection to the second relay 524, and at a second connection to the output 304. The output 304 is coupled to the first fuse 516 and the second fuse 526, and is configured to be coupled to a load or its medium, such as the output 304, which can be coupled to a load.

[0066] It should be understood that the foregoing connections are examples, and other configurations are also within the scope of this disclosure. In some examples, the position of the first relay 514 may be interchanged with the position of the first fuse 516 in the first converter branch 306. Similarly, the positions of the first inductor 508, the first capacitor 510, and the second inductor 512 may be interchanged with the first relay 514 and / or the first fuse 516 in the first converter branch 306. A similar principle applies to the second converter branch 308. Furthermore, although in some examples, output components 312, 316 may be coupled between converter switches 310, 314 and output 304 (e.g., between the switch outputs of converter switches 310, 314 and output 304), in other examples, output components 312, 316 may be coupled between input 302 and output components 312, 316.

[0067] For example, Figure 6 A block diagram of a power converter 600 according to another example is shown. The power converter 600 includes components similar to those referenced above. Figure 3 The power converter 300 is described with substantially similar components, and identical components are labeled accordingly. However, the power converter 600 may be an example of the AC / DC converter 104 and / or the DC / DC converter 108. Therefore, the components of the power converter 600 may be arranged differently from those of the power converter 300, although in some examples, the components of the power converter 600 are substantially the same as those of the power converter 300. In some examples, components of the power converter 600, such as one or more of the output components 312, 316, may differ from those of the power converter 300, as described below.

[0068] For example, power converter 600 includes an input 302, an output 304, a first converter branch 306, and a second converter branch 308. The first converter branch 306 includes a first converter switch 310 and a first output component 312. The second converter branch 308 includes a second converter switch 314 and a second output component 316. However, the components of power converter 600 are arranged differently from those of power converter 300.

[0069] For example, input 302 is coupled to a first output component 312 and a second output component 316, a first converter switch 310 is coupled between the first output component 312 and output 304, and a second converter switch 314 is coupled between the second output component 316 and output 304. In an example where the power converter 600 is implemented as an AC / DC converter 104, input 302 may be coupled to input 102, and output 304 may be coupled to a DC bus 106. In an example where the power converter 600 is implemented as a DC / DC converter 108, input 302 may be coupled to an energy storage device interface 110, and output 304 may be coupled to a DC bus 106.

[0070] Process 400 can be performed in conjunction with power converter 600 in a manner substantially similar to that of power converter 300, although some actions of process 400 may differ. For example, at action 408, controller 112 may control converter switches 310, 314 to convert power received at input 302 into converted power to be provided at output 304; however, this conversion may include converting AC power to DC power, such as in which power converter 600 is an example of AC / DC converter 104, and / or may include converting DC power to converted DC power, such as in which power converter 600 is an example of DC / DC converter 108, rather than inverting DC power to AC power. However, other actions of process 400, such as reducing the current difference between branches 306, 308 at action 414, may be substantially similar or identical.

[0071] Figure 7 A schematic diagram of a power converter 600 according to an example is shown. Figure 7 The power converter 600 can be an example implementation of the AC / DC converter 104, which can operate as PFC. Figure 7The power converter 600 includes an input 302, a first output 304a and a second output 304b (collectively referred to as output 304), a first converter branch 306, a second converter branch 308, a first converter switch 310, a first output component 312, a second converter switch 314, a second output component 316, converter switches 500-506, a first inductor 508, a first capacitor 510, a second inductor 512, a first relay 514, a first fuse 516, a third inductor 518, a second capacitor 520, a fourth inductor 522, a second relay 524, and a second fuse 526. However, Figure 7 The components of the power converter 600 can be compared to Figure 5 The components of the power converter 300 are interconnected differently.

[0072] Input 302 is coupled to the first fuse 516 and the second fuse 526, and is configured to be coupled to a power source. For example, in Figure 7 In the case where the power converter 600 is an example of an AC / DC converter 104, input 302 can be coupled to input 102, which can be coupled to a power source. A first fuse 516 is coupled to input 302 at a first connection and to a first relay 514 at a second connection. The first relay 514 is coupled to the first fuse 516 at a first connection and to a second inductor 512 at a second connection. In some examples, the first relay 514 is coupled to a controller 112 at a control connection. The second inductor 512 is coupled to the first relay 514 at a first connection and to a first inductor 508 and a first capacitor 510 at a second connection. The first inductor 508 is coupled to the first capacitor 510 at a first connection and to a first converter switch 500 and a second converter switch 502 at a second connection. The first capacitor 510 is coupled to the first inductor 508 and the second inductor 512 at a first connection and to a second reference node 530 at a second connection.

[0073] The second fuse 526 is coupled to input 302 at a first connection and to the second relay 524 at a second connection. The second relay 524 is coupled to the second fuse 526 at a first connection and to the fourth inductor 522 at a second connection. In some examples, the second relay 524 is coupled to controller 112 at a control connection. The fourth inductor 522 is coupled to the second relay 524 at a first connection and to the third inductor 518 and the second capacitor 520 at a second connection. The third inductor 518 is coupled to the fourth inductor 522 and the second capacitor 520 at a first connection and to the third converter switch 504 and the fourth converter switch 506 at a second connection.

[0074] The first output 304a is coupled to the first converter switch 500 and the third converter switch 504, and is configured to be coupled to a load or its medium. For example, the first output 304a may be coupled to a positive voltage DC bus or another type of bus of DC bus 106. The second output 304b is coupled to the second converter switch 502 and the fourth converter switch 506, and is configured to be coupled to a load or its medium. For example, the second output 304b may be coupled to a negative voltage, neutral, common, or other type of DC bus of DC bus 106.

[0075] The first converter switch 500 is coupled to the first output 304a at a first connection, to the first inductor 508 and the second converter switch 502 at a second connection, and communicatively coupled to the controller 112. The second converter switch 502 is coupled to the first inductor 508 and the first converter switch 500 at a first connection, to the second output 304b at a second connection, and communicatively coupled to the controller 112 at a control connection. The third converter switch 504 is coupled to the first output 304a at a first connection, to the third inductor 518 and the fourth converter switch 506 at a second connection, and communicatively coupled to the controller 112 at a control connection. The fourth converter switch 506 is coupled to the third converter switch 504 and the third inductor 518 at a first connection, to the second output 304b at a second connection, and communicatively coupled to the controller 112 at a control connection.

[0076] As mentioned above, Figure 7 The components of the power converter 600 can be substantially similar to Figure 5 The components of the power converter 300. However, Figure 7 The components of the power converter 600 can be interconnected differently because the positions of converter switches 310 and 314 can be switched with the positions of output components 312 and 316, respectively. As described above, the controller 112 can control converter switches 500-506 differently, such as by controlling converter switches 500-506 to convert the AC power received at input 302 into converted DC power to be provided to output 304. Furthermore, although Figure 5 The power converter 300 may include a first input 302a, a second input 302b and an output 304, but the power converter 600 may include an input 302, a first output 304a and a second output 304b.

[0077] In other examples, the power converter 600 can be implemented as another converter for the UPS 100, such as the DC / DC converter 108. Figure 8 A schematic diagram of a power converter 600 according to another example is shown. Figure 8The power converter 600 can be an example implementation of the DC / DC converter 108, which can operate as a voltage level converter. Figure 8 The power converter 600 includes an input 302, a first output 304a, a second output 304b, a first converter branch 306, a second converter branch 308, a first converter switch 310, a first output component 312, a second converter switch 314, a second output component 316, converter switches 500-506, a first inductor 508, a first capacitor 510, a first fuse 516, a third inductor 518, a second capacitor 520, and a second fuse 526. Figure 8 The components of the power converter 600 can be compared to Figure 5 Power converter 300 and Figure 7 The components of the power converter 600 are interconnected differently.

[0078] Input 302 is coupled to the first fuse 516 and the second fuse 526, and is configured to be coupled to a power source. For example, in Figure 8 In the case where the power converter 600 is an example of a DC / DC converter 108, input 302 can be coupled to an energy storage device interface 110, which can be coupled to a power source. A first fuse 516 is coupled to input 302 at a first connection and to a first inductor 508 and a first capacitor 510 at a second connection. The first inductor 508 is coupled to the first capacitor 510 at a first connection and to a first converter switch 500 and a second converter switch 502 at a second connection. The first capacitor 510 is coupled to the first inductor 508 and the first fuse 516 at a first connection and to a second reference node 530 at a second connection. A second fuse 526 is coupled to input 302 at a first connection and to a third inductor 518 and a second capacitor 520 at a second connection. The third inductor 518 is coupled to the second fuse 526 and the second capacitor 520 at a first connection and to a third converter switch 504 and a fourth converter switch 506 at a second connection.

[0079] The first output 304a is coupled to the first converter switch 500 and the third converter switch 504, and is configured to be coupled to a load or its medium. For example, the first output 304a may be coupled to a positive voltage DC bus or another type of bus of DC bus 106. The second output 304b is coupled to the second converter switch 502 and the fourth converter switch 506, and is configured to be coupled to a load or its medium. For example, the second output 304b may be coupled to a negative voltage, neutral, common, or other type of DC bus of DC bus 106.

[0080] The first converter switch 500 is coupled to the first output 304a at a first connection, to the first inductor 508 and the second converter switch 502 at a second connection, and communicatively coupled to the controller 112. The second converter switch 502 is coupled to the first inductor 508 and the first converter switch 500 at a first connection, to the second output 304b at a second connection, and communicatively coupled to the controller 112 at a control connection. The third converter switch 504 is coupled to the first output 304a at a first connection, to the third inductor 518 and the fourth converter switch 506 at a second connection, and communicatively coupled to the controller 112 at a control connection. The fourth converter switch 506 is coupled to the third converter switch 504 and the third inductor 518 at a first connection, to the second output 304b at a second connection, and communicatively coupled to the controller 112 at a control connection.

[0081] As mentioned above, Figure 8 The components of the power converter 600 can be similar to Figure 7 Components of the power converter 600. However, in Figure 8 In the power converter 600, the first output component 312 does not include the first relay 514 and the second inductor 512, and the second output component 316 does not include the second relay 524 and the fourth inductor 522. Furthermore, the controller 112 can control the converter switches 500-506 differently, such as by controlling the converter switches 500-506 to convert the DC power received at the input 302 (e.g., from the battery 124 via the energy storage device interface 110) into converted DC power to be provided to the output 304.

[0082] Therefore, it should be understood that various interleaved power converters with multiple converter branches are provided. Each converter branch may include one or more components, such as one or more filter components, relays, fuses, etc. Because the components in each branch conduct current only from one converter branch, the components receive less current than, for example, components implemented in a common configuration where components are coupled to all converter branches. Therefore, the rated current of each component can be reduced.

[0083] use Figure 5Using the power converter 300 as an example, each of the converter branches 306, 308 can conduct approximately 116A of RMS current. As used herein, "approximately 116A" can include between 115-117A in one example; between 113-119A in another; between 110-120A in yet another; or other ranges in still other examples. Instead of implementing a single set of output components coupled to the two converter branches 306, 308 rated to receive approximately 232A of current, output components 312, 316 may only need to be rated to receive approximately 116A of current each. For example, fuses 516, 526 and relays 514, 524 can be implemented with components rated to receive 160A of current, which allows fuses 516, 526 and relays 514, 524 to be implemented as PCB-mounted components where PCB-mounted fuses or relays rated to receive 232A of current may be difficult or impossible to obtain.

[0084] Furthermore, in the case of fuses 516 and 526, the purging energy of fuses 516 and 526 can be reduced compared to, for example, a common fuse. Continuing with the aforementioned example of implementing fuses 516 and 526 as fuses with a rated current of 160A, the I of each fuse... 2 The removal energy is 16 kA. 2 / s. Conversely, a common fuse with a rated current of 315A exhibits 82kA. 2 / s of I 2 Energy is cleared. By implementing fuses 516 and 526 with a lower rated current than the common fuse, energy clearing is significantly reduced, thus posing less risk of damage to adjacent components in the event of a blown fuse.

[0085] As described above, inductors 512 and 522 can be inductively coupled together to share the ripple current between converter branches 306 and 308. This current sharing reduces the ripple current in capacitors 510 and 520. In other examples, omitting the inductive coupling of inductors 512 and 522 to improve internal resonant performance may be advantageous, depending on design requirements. In other examples, completely omitting inductors 510 and 520 may be advantageous.

[0086] As described above, power converters 300 and 600 can be implemented in combination with any of converters 104, 108, and / or 114. In some examples, power converters 300 and 600 can be implemented in all converters 104, 108, and 114. For example, power converter 300 can be implemented in DC / AC inverter 114, and power converter 600 can be implemented as PFC in AC / DC converter 104 and in DC / DC converter 108. In other examples, fewer than all converters 104, 108, and 114 can be combined with power converters 300 and 600.

[0087] In some examples, a single common component can be replaced by one or more components connected in parallel. For example, a single common fuse can be replaced by two or more fuses connected in hard parallel, and / or a single common relay can be replaced by two or more relays connected in hard parallel. However, components connected in hard parallel may be difficult or impossible to obtain UL certification. For example, if one of the parallel-connected fuses blows, the remaining parallel-connected fuses may be subjected to excessively high voltage spikes, which prevents UL certification. Therefore, the examples discussed above may be advantageous because hard paralleling is not implemented. Furthermore, current sharing is provided in some examples, and the balance between converter branches 306 and 308 is achieved by the controller 112 detecting the current difference between them and reducing that current difference.

[0088] Various controllers, such as controller 112, can perform the various operations described above. Using data stored in associated memory and / or storage devices, controller 112 also executes one or more instructions stored on one or more non-transitory computer-readable media, which can produce manipulated data. In some examples, controller 112 may include one or more processors or other types of controllers. In one example, controller 112 is or includes at least one processor. In another example, in addition to, or instead of, a general-purpose processor, controller 112 uses an application-specific integrated circuit (ASIC) customized to perform specific operations to perform at least a portion of the operations described above. As these examples show, examples of this disclosure can use many specific combinations of hardware and software to perform the operations described herein, and this disclosure is not limited to any specific combination of hardware and software components. Examples of this disclosure may include a computer program product configured to perform the methods, processes, and / or operations described above. The computer program product may be or include one or more controllers and / or processors configured to execute instructions to perform the methods, processes, and / or operations described above.

[0089] Therefore, several aspects of at least one embodiment have been described, and it should be understood that various changes, modifications, and improvements will readily occur to those skilled in the art. These changes, modifications, and improvements are intended to be part of this disclosure and within its spirit and scope. Therefore, the foregoing description and drawings are merely exemplary.

Claims

1. An uninterruptible power supply, comprising: The first input is configured to be coupled to the main power supply; The second input is configured to be coupled to the backup power supply; The output is configured to be coupled to the load; A first converter branch is configured to provide a first voltage signal to the output, wherein the first converter branch includes a first relay and a first fuse coupled in series; A second converter branch is configured to provide a second voltage signal to the output and is configured to be coupled in parallel with the first converter branch, wherein the second converter branch provides a second voltage signal that is out of phase with the first converter branch that provides the first voltage signal, and wherein the second converter branch includes a second relay and a second fuse coupled in series. A first current sensor is coupled to the first converter branch and configured to provide a first current sensing signal indicating a first current in the first converter branch; A second current sensor is coupled to the second converter branch and configured to provide a second current sensing signal indicating a second current in the second converter branch; as well as At least one controller is configured as follows: Receive the first current sensing signal and the second current sensing signal; The current difference between the first converter branch and the second converter branch is determined based on the first current sensing signal and the second current sensing signal; as well as Reduce the current difference.

2. The uninterruptible power supply according to claim 1, wherein the first converter branch includes a first filter, and the second converter branch includes a second filter.

3. The uninterruptible power supply according to claim 2, wherein the first relay and the first fuse are coupled between the first filter and the output, and wherein the second relay and the second fuse are coupled between the second filter and the output.

4. The uninterruptible power supply according to claim 2, wherein the first filter includes at least one first capacitor, and wherein the second filter includes at least one second capacitor.

5. The uninterruptible power supply of claim 4, wherein the first filter includes at least one first inductor coupled to the at least one first capacitor, and wherein the second filter includes at least one second inductor coupled to the at least one second capacitor.

6. The uninterruptible power supply according to claim 2, wherein the first filter includes a first choke, and wherein the second filter includes a second choke, the first choke being inductively coupled to the second choke.

7. The uninterruptible power supply according to claim 6, The first choke is configured to induce a first induced current in the second choke in response to a first ripple current flowing through the first converter branch, and The second choke is configured to induce a second induced current in the first choke in response to a second ripple current flowing through the second converter branch.

8. The uninterruptible power supply according to claim 1, wherein the first converter branch includes at least one first power conversion switch having a first switch input and a first switch output, and wherein the second converter branch includes at least one second power conversion switch having a second switch input and a second switch output.

9. The uninterruptible power supply of claim 8, wherein the first relay and the first fuse are coupled between the first switch input and at least one of the first input or the second input, and wherein the second relay and the second fuse are coupled between the second switch input and at least one of the first input or the second input.

10. The uninterruptible power supply of claim 8, wherein the first relay and the first fuse are coupled between the first switch output and the output, and wherein the second relay and the second fuse are coupled between the second switch output and the output.

11. A method for assembling an uninterruptible power supply, the method comprising: Provides a first converter branch with a first relay and a first fuse connected in series; A second converter branch with a second relay and a second fuse connected in series is provided; A first current sensor is provided, the first current sensor being configured to provide a first current sensing signal indicating a first current in the first converter branch; A second current sensor is provided, the second current sensor being configured to provide a second current sensing signal indicating a second current in the second converter branch; Provide at least one controller; The first converter branch is coupled in parallel with the second converter branch; Couple the first current sensor to the first converter branch; Couple the second current sensor to the second converter branch; as well as The at least one controller is coupled to the first converter branch and the second converter branch to receive the first current sensing signal and the second current sensing signal, determine the current difference between the first converter branch and the second converter branch based on the first current sensing signal and the second current sensing signal, and reduce the current difference between the first converter branch and the second converter branch.

12. The method of claim 11, wherein the uninterruptible power supply includes an output, and the method further includes: A first filter is provided in the first converter branch; A second filter is provided in the second converter branch; The first relay and the first fuse are coupled between the first filter and the output; as well as The second relay and the second fuse are coupled between the second filter and the output.

13. The method of claim 12, wherein providing the first filter includes providing at least one first capacitor, and providing the second filter includes providing at least one second capacitor, the method further comprising: The at least one first capacitor is coupled to at least one of the first relay or the first fuse; as well as The at least one second capacitor is coupled to at least one of the second relay or the second fuse.

14. The method of claim 13, wherein providing the first filter includes providing at least one first inductor, and providing the second filter includes providing at least one second inductor, the method further comprising: Couple the at least one first inductor to the at least one first capacitor; as well as The at least one second inductor is coupled to the at least one second capacitor.

15. The method of claim 11, further comprising: Provide a first choke coil and a second choke coil; The first choke coil is coupled to at least one of the first relay or the first fuse; The second choke is coupled to at least one of the second relay or the second fuse; as well as The first choke is inductively coupled to the second choke.

16. A non-transitory computer-readable medium on which a sequence of computer-executable instructions is stored, the computer-executable instructions for controlling an uninterruptible power supply (UPS), the UPS including at least one input, an output, a first converter branch including a first current sensor and a first relay and a first fuse coupled in series, and a second converter branch configured to be coupled in parallel with the first converter branch, the second converter branch including a second current sensor and a second relay and a second fuse coupled in series, the sequence of computer-executable instructions including instructions instructing at least one processor: The first converter branch is controlled to provide a first voltage signal to the output via the first relay and the first fuse; The second converter branch is controlled to provide a second voltage signal to the output via the second relay and the second fuse, wherein the second converter branch provides a second voltage signal that is out of phase with the first converter branch that provides the first voltage signal; Receive a first current sensing signal from the first current sensor, indicating a first current in the first converter branch; Receive a second current sensing signal from the second current sensor, indicating the second current in the second converter branch; The current difference between the first converter branch and the second converter branch is determined based on the first current sensing signal and the second current sensing signal; as well as Reduce the current difference between the first converter branch and the second converter branch.

Images