Reversed power and grid support with a modular approach

Aspects of the disclosure include a power supply system is provided comprising first and second inputs, an output, a first group of power modules coupled to the inputs and the output, a second group of power modules coupled to the inputs, and at least one controller configured to control, in a reverse mode, the first group of power modules to provide power derived from the second input to the output, wherein a majority of power provided by each power module of the first group of power modules in the reverse mode is provided to the output, and control, in the reverse mode, the second group of power modules to provide power derived from the second input to the first input, wherein a majority of power provided by each power module of the second group of power modules in the reverse mode is provided to the first input.

BACKGROUND

1. Field of the Disclosure

At least one example in accordance with the present disclosure relates generally to uninterruptible power supplies.

2. Discussion of Related Art

Power devices, such as uninterruptible power supplies (UPSs), may be used to provide regulated, uninterrupted power for sensitive and/or critical loads, such as computer systems and other data-processing systems. Existing UPSs include online UPSs, offline UPSs, line-interactive UPSs, as well as others. UPSs may provide output power to a load. The output power may be derived from a primary source of power, such as a utility-mains source, and/or derived from a back-up source of power, such as an energy-storage device.

SUMMARY

According to at least one aspect of the present disclosure, an uninterruptible power supply (UPS) system is provided comprising a first input configured to be coupled to a main-power source, a second input configured to be coupled to a backup-power source, an output configured to be coupled to at least one load, a first group of one or more power modules coupled to the first input, the second input, and the output, a second group of one or more power modules coupled to the first input and the second input, and at least one controller configured to control, in a reverse mode of operation, the first group of one or more power modules to provide power derived from the second input to the output, wherein a majority of power provided by each power module of the first group of one or more power modules in the reverse mode of operation is provided to the output, and control, in the reverse mode of operation, the second group of one or more power modules to provide power derived from the second input to the first input, wherein a majority of power provided by each power module of the second group of one or more power modules in the reverse mode of operation is provided to the first input.

In at least one example, the at least one controller is further configured to control, in a forward mode of operation, the first group of one or more power modules to provide power derived from the first input to the output and to provide power derived from the first input to the second input, wherein a majority of power provided by the first group of one or more power modules in the forward mode of operation is provided to the output and second input, and control, in the forward mode of operation, the second group of one or more power modules to provide power derived from the first input to the second input, wherein a majority of power provided by the second group of one or more power modules in the forward mode of operation is provided to the second input.

In some examples, the at least one controller is further configured to control, in a regenerative mode of operation, the first group of one or more power modules to provide power derived from the output to the second input. In various examples, the at least one controller is further configured to control, in the regenerative mode of operation, the second group of one or more power modules to provide power derived from the second input to the first input. In at least one example, the at least one controller is further configured to: receive, from a grid controller coupled to the main-power source, a request for power, and control, responsive to receiving the request for power, the UPS system to operate in the reverse mode of operation.

In at least one example, the at least one controller is further configured to control the second group of one or more power modules to provide a current-controlled power output to the first input. In some examples, the at least one controller is further configured to provide one or more pulse-width-modulation signals to the second group of one or more power modules to provide the current-controlled power output to the first input. In various examples, the at least one controller is further configured to control the first group of one or more power modules to provide a voltage-controlled power output to the output.

In some examples, the majority of the power provided by each power module of the first group of one or more power modules in the forward mode of operation is at least ninety percent of the power provided by each power module of the first group of power modules in the forward mode of operation, and the majority of power provided by each power module of the second group of one or more power modules in the forward mode of operation is at least ninety percent of the power provided by each power module of the second group of power modules in the forward mode of operation.

According to at least one aspect of the present disclosure, a non-transitory computer-readable medium storing thereon sequences of computer-executable instructions for controlling an uninterruptible power supply system having a first input configured to be coupled to a main-power source, a second input configured to be coupled to a backup-power source, an output configured to be coupled to at least one load, a first group of one or more power modules coupled to the first input, the second input, and the output, and a second group of one or more power modules coupled to the first input and the second input is provided, the sequences of computer-executable instructions including instructions that instruct at least one processor to control, in a reverse mode of operation, the first group of one or more power modules to provide power derived from the second input to the output, wherein a majority of the power provided by each power module of the first group of power modules in the reverse mode of operation is provided to the output, and control, in the reverse mode of operation, the second group of one or more power modules to provide power derived from the second input to the first input, wherein a majority of the power provided by each power module of the second group of one or more power modules in the reverse mode of operation is provided to the first input.

In various examples, a non-transitory computer-readable medium containing computer-readable instructions, wherein the instructions further instruct the at least one processor to control, in a forward mode of operation, the first group of one or more power modules to provide power derived from the first input to the output and the second input, wherein a majority of the power provided by each power module of the first group of one or more power modules in the forward mode of operation is provided to the output and the second input, and control, in the forward mode of operation, the second group of one or more power modules to provide power derived from the first input to the second input, wherein a majority of the power provided by each power module of the second group of one or more power modules in the forward mode of operation is provided to the second input is provided.

In at least one example, a non-transitory computer-readable medium containing instructions, wherein the instructions further instruct the at least one processor to control, in a regenerative mode of operation, the first group of one or more power modules to provide power derived from the output to the second input is provided. In some examples, the instructions further instruct the at least one processor to control, in the regenerative mode of operation, the second group of one or more power modules to provide power derived from the second input to the first input.

In various examples, a non-transitory computer-readable medium containing instructions, wherein the instructions further instruct the at least one processor to control the first group of one or more power modules to provide a voltage-controlled power output to the output is provided. In some examples, the instructions further instruct the at least one processor to control the second group of one or more power modules to provide a current-controlled power output to the first input. In at least one example, the instructions further instruct the at least one processor to provide one or more pulse-width-modulation signals to the second group of power modules to provide the current-controlled power output to the first input. In various examples, the instructions further instruct the at least one processor to: receive, from a grid controller coupled to the main-power source, a request for power, and control, responsive to receiving the request for power, the UPS system to operate in the reverse mode of operation.

In some examples, a non-transitory computer-readable medium containing instructions, wherein the majority of the power provided by each power module of the first group of one or more power modules in the forward mode of operation is at least ninety percent of the power provided by each power module of the first group of power modules in the forward mode of operation, and wherein the majority of power provided by each power module of the second group of one or more power modules in the forward mode of operation is at least ninety percent of the power provided by each power module of the second group of power modules in the forward mode of operation, is provided.

In various examples, a power module configured to be implemented in a power system is provided, the power module comprising: a first input configured to be coupled to a main-power source, an AC/DC converter coupled to the first input, a second input configured to be coupled to a backup-power source, a DC/DC converter coupled to the second input, an output configured to be coupled to one of the main-power source in a first configuration of the power module, or at least one load in a second configuration of the power module, and a DC/AC inverter coupled to the output, wherein in a reverse mode of operation of the power system the DC/AC inverter is configured to provide, in the first configuration of the power module, power to the main-power source, and provide, in the second configuration of the power module, power to the at least one load. In some examples, the DC/AC inverter is configured to provide a current-controlled output. In at least one example, the DC/AC inverter is configured to provide a voltage-controlled output.

In various examples, method for controlling an uninterruptible power supply system having a first input configured to be coupled to a main-power source, a second input configured to be coupled to a backup-power source, an output configured to be coupled to at least one load, a first group of one or more power modules coupled to the first input, the second input, and the output, and a second group of one or more power modules coupled to the first input and the second input is provided, the method comprising: controlling, in a reverse mode of operation, the first group of one or more power modules to provide power derived from the second input to the output, wherein a majority of the power provided by each of the power modules of the first group of power modules in the reverse mode of operation is provided to the output, and controlling, in the reverse mode of operation, the second group of one or more power modules to provide power derived from the second input to the first input, wherein a majority of the power provided by each of the power modules of the second group of power modules in the reverse mode of operation is provided to the first input.

DETAILED DESCRIPTION

Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. Any references to examples, embodiments, components, elements or acts of the systems and methods herein referred to in the singular may also embrace embodiments including a plurality, and any references in plural to any embodiment, component, element or act herein may also embrace embodiments including only a singularity. References in the singular or plural form are not intended to limit the presently disclosed systems or methods, their components, acts, or elements. The use herein of “including,” “comprising,” “having,” “containing,” “involving,” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

References to “or” may be construed as inclusive so that any terms described using “or” may indicate any of a single, more than one, and all of the described terms. In addition, in the event of inconsistent usages of terms between this document and documents incorporated herein by reference, the term usage in the incorporated features is supplementary to that of this document; for irreconcilable differences, the term usage in this document controls.

Uninterruptible power supplies (UPSs) may be configured to provide uninterrupted power to one or more loads. UPSs may be coupled to a main-power source and a backup-power source, such as a battery, and provide power derived from the main-power source and/or the backup-power source to the one or more loads. For example, a UPS may provide load power derived from the main-power source when main power is available, and may provide load power derived from the backup-power source when main power is not available.

A main-power source may include an electrical-power grid. Electrical-power grids may include centralized utility mains grids, decentralized grids including renewable-energy sources, and so forth. In some examples, it may be advantageous for a UPS to provide power back to the electrical-power grid (“backfeed”) in addition to drawing power from the grid. For example, it may be advantageous to backfeed power to the electrical-power grid to facilitate stabilization of the electrical-power grid.

Examples described herein include a UPS coupled to a main-power source, a backup-power source, and at least one load. The UPS may include a plurality of power modules. The plurality of power modules may include a first group of power modules and a second group of power modules. The first group of power modules may be coupled in a first configuration, and the second group of power modules may be coupled in a second configuration. In the first configuration, each power module of the first group of power modules is connected to the at least one load at a respective module-output connection. In the second configuration, each power module of the second group of power modules is connected to the main-power source at a respective module-output connection. In various examples, the first group of power modules may otherwise be substantially similar or identical to the second group of power modules. Examples of the disclosure may therefore provide cost-effective, standardized power modules capable of outputting power in various configurations.

FIG.1illustrates a block diagram of a power system100according to an example. The power system100includes a UPS system102. The UPS system102includes a plurality of power modules104divided into at least two groups, a first group of power modules106and a second group of power modules108. Each of the first group of power modules106and the second group of power modules108includes one or more power modules200, as discussed in greater detail below with respect toFIG.2. The UPS system102also include one or more system controllers110(“system controller110”) which may be communicatively coupled to one or more main power source controllers112(“grid controller112”). The UPS system102may be further coupled to a main power source114(“grid114”), a backup power source116, and one or more loads118(“loads118”).

The UPS system102is configured to be coupled to the grid114, the backup power source116, and the loads118, and may be communicatively coupled to the grid controller112. The first group of power modules106is configured to be coupled to the grid114, the backup power source116, and the loads118, and may be communicatively coupled to the system controller110. The second group of power modules108is configured to be coupled to the grid114and the backup power source116, and may be communicatively coupled to the system controller110. The system controller110may be communicatively coupled to the first group of power modules106, the second group of power modules108, and the grid controller112.

The grid114is coupled to the UPS system102and may include or be coupled to any of various types of power sources including, for example, generators, hydroelectric power sources, photovoltaic converters, wind turbines, and so forth. The UPS system102is configured to provide power to and/or receive power from the grid114. For example, the UPS system102may backfeed power to the grid114to stabilize power on the grid114.

The backup power source116may include one or more energy-storage devices, such as batteries, capacitors, flywheels, and so forth. In at least one example, the backup power source116may include a rechargeable battery. The UPS system102is configured to provide power to and/or receive power from the backup power source116. In some examples, the UPS system102is configured to provide DC power to and/or receive DC power from the backup power source116.

The loads118may include one or more devices configured to draw power provided from the UPS system102. In various examples, the UPS system102may be configured to receive regenerative power from the loads118in addition to providing output load power to the loads118.

As discussed in greater detail below, the UPS system102is configured to operate in any of at least three distinct modes of operation including a reverse mode of operation, a forward mode of operation, and a regenerative mode of operation. The system controller110selects and/or controls the mode of operation of the UPS system102. For example, the system controller110may select and/or control the mode of operation of the UPS system102based on a status of the grid114or power received therefrom, a status of the backup power source116or power received therefrom, an operating mode of the loads118, and so forth. In some examples, the system controller110may receive information and/or commands from the grid controller112indicative of a desired mode of operation between the forward mode of operation, the reverse mode of operation, and the regenerative mode of operation. In some examples, the UPS system102may operate in additional or different modes of operation as well.

In the reverse mode of operation, the UPS system102is configured to control the first group of power modules106to provide power derived from the backup power source116to the loads118, and control the second group of power modules108to provide power derived from the backup power source116to the grid114. Examples of the reverse mode of operation are discussed below with respect toFIG.5.

In the regenerative mode of operation, the UPS system102controls the first group of power modules106to provide power derived from the loads118to the backup power source116, and controls the second group of power modules108to provide power derived from the backup power source116to the grid114. Examples of the regenerative mode of operation are discussed below with respect toFIG.6.

In the forward mode of operation, the UPS system102is configured to control the first group of power modules106to provide power derived from the grid114to the loads118and to the backup power source116, and controls the second group of power modules108to provide power derived from the grid114to the backup power source116. Examples of the forward mode of operation are discussed below with respect toFIG.7.

FIG.2illustrates a block diagram of a power module200according to an example. As discussed above, the power module200is an example of the power modules of one of or both of the first group of power modules106and/or the second group of power modules108. The power module includes a first input202, a second input204, an output206(also referred to as output connection206), an AC/DC converter208, one or more power busses210(“power bus210”), a DC/AC inverter212, a DC/DC converter214, one or more module controllers216(“module controller216”), and at least one communication interface218(“communication interface218”).

The first input202is coupled to the AC/DC converter208and is configured to be coupled to at least one main-power source, such as the grid114. The second input204is coupled to the DC/DC converter214and is configured to be coupled to at least one backup power source, such as the backup power source116. The output206is coupled to the DC/AC inverter212and is configured to be coupled to at least one of a main-power source or one or more loads118. For example, where the power module200is implemented as an example of one of the first group of power modules106, the output206may be configured to be coupled to the loads118. In an example in which the power module200is implemented as an example of one of the second group of power modules108, the output206may be configured to be coupled to the grid114.

The AC/DC converter208is coupled to the first input202at a first connection (for example, an AC-power connection) and is coupled to the power bus210at a second connection (for example, a DC-power connection). The AC/DC converter208may further be communicatively coupled to the module controller216. The power bus210is coupled to the AC/DC converter208at a first connection, the DC/AC inverter212at a second connection, and the DC/DC converter214at a third connection. The DC/AC inverter212is coupled to the power bus210at a first connection (for example, a DC-power connection) and to the output connection206at a second connection (for example, an AC-power connection). The DC/AC inverter212may further be communicatively coupled to the module controller216. The DC/DC converter214is coupled to the second input204at a first connection and to the power bus210at a second connection. The DC/DC converter214may further be communicatively coupled to the module controller216.

The module controller216is communicatively coupled to the AC/DC converter208, the DC/AC inverter212, the DC/DC converter214, and the communication interface218. The communication interface218is communicatively coupled to the module controller216and may be configured to be communicatively coupled to the system controller110and/or the grid controller112. For example, the communication interface218may include one or more wired—or wireless-communication ports or interfaces to exchange information with one or more entities including, for example, the system controller110and/or the grid controller112.

The module controller216may be configured to provide one or more control signals to the AC/DC converter208, the DC/AC inverter212, and/or the DC/DC converter214to control operation of the components208,210,212,214. For example, each of the components208,210,212,214may include one or more switching devices (for example, MOSFETs, IGBTs, BJTs, relays, and so forth). The module controller216may provide one or more control signals to the components208,210,212,214to control a switching state of each of the one or more switching devices.

For example, the module controller216may control the AC/DC converter208to receive an AC power signal from the first input202, convert the AC power signal to a DC power signal, and provide the DC power signal to the DC/AC inverter212and/or the DC/DC converter214via the power bus210.

The module controller216may control the DC/AC inverter212to draw DC power from the power bus210, convert the DC power to AC power, and provide the AC power to the output206. In some examples, the module controller216may further control the DC/AC inverter212to draw AC power from the output206, convert the AC power to DC power, and provide the DC power to the AC/DC converter208and/or the DC/DC converter214via the power bus210. For example, the module controller216may control the DC/AC inverter212to draw AC power from the loads118via the output206in the regenerative mode of operation as discussed in greater detail below. Accordingly, no limitation as to power-conversion directionality is implied by use of the example term “inverter.”

The module controller216may control the DC/DC converter214to draw DC power from the second input204(for example, from the backup power source116via the second input204), convert the DC power to converted DC power, and provide the converted DC power to the DC/AC inverter212via the power bus210. The module controller216may alternately or additionally control the DC/DC converter214to draw DC power from the power bus210, convert the DC power to converted DC power, and provide the converted DC power to the second input204. For example, the DC/DC converter214may provide the converted DC power to the backup power source116via the second input204to charge the backup power source116. Accordingly, no limitation is implied by use of the example term “input.”

In some examples, the module controller216may also be communicatively coupled to one or more sensors capable of providing information indicative of operational parameters, such as voltage and/or current levels, temperature, or other appropriate information. Although in some examples the module controller216may be communicatively coupled to one or more external devices via the communication interface218, in other examples the communication interface218may include the module controller216or vice versa. In some examples, the module controller216may control the operation of the power module200based on one or more received signals, such as operation mode signals received from the system controller110and/or requests from the grid controller112.

The power module200may receive power at one or more of the first input202, second input204, and output connection206and may provide power at the second input204and/or the output connection206. In some examples, the power module200may not be configured to output power at the first input202. For example, the AC/DC converter208may be a unidirectional converter configured to draw power from, but not provide power to, the first input202. In other examples, the AC/DC converter208may be bidirectional, and the power module200may output power at the first input202.

In some examples, the power module200receives AC power at the first input202. The AC/DC converter208may draw the AC power from the first input202, convert the AC power into DC power, and provide the DC power to the power bus210. The DC/AC inverter212and/or the DC/DC converter214may draw the DC power from the power bus210. The DC/DC converter214may convert the DC power drawn from the power bus210into converted DC power, and provide the converted DC power to the second input204. The DC/AC inverter212may convert the DC power drawn from the power bus210into AC power, and provide the AC power to the output connection206.

In some examples, the power module200may alternately or additionally provide AC power derived from DC power drawn from the second input204to the output connection206. For example, the second input204may receive DC power at the second input204(for example, from the backup power source116). The DC/DC converter214may draw the DC power from the second input204, convert the drawn DC power into converted DC power, and provide the converted DC power to the power busses210. The DC/AC inverter212may draw the converted DC power from the power busses210, convert the converted DC power to AC power, and provide the AC power to the output connection206(for example, to the loads118).

In some examples, the power module200may alternately or additionally provide DC power derived from AC power drawn from the output connection206to the second input204. For example, the output connection206may receive AC power (for example, from the loads118). The DC/AC inverter212may draw the AC power from the output connection206, convert the drawn AC power into DC power, and provide the DC power to the power busses210. The DC/DC converter214may draw the DC power from the power busses210, convert the drawn DC power to converted DC power, and provide the DC power to the second input204(for example, to the backup power source116).

As discussed above, operation of the power module200may depend at least in part on an entity to which the output connection206is coupled. In a first configuration, the output connection206may be coupled to the loads118. In the first configuration, the power module200may be grouped within the first group of power modules106at least in part because the output connection206is coupled to the loads118. The power module200of the first configuration may be configured to provide output power to the loads118via the output connection206. In a second configuration, the output connection206may be coupled to the grid114. In the second configuration, the power module200may be grouped within the second group of power modules108at least in part because the output connection206is coupled to the grid114. The power module200of the second configuration may be configured to provide output power to the grid114via the output connection206.

A user may configure the power module200before and/or after setup of the UPS system102. For example, to configure the power module200in the first configuration, the user may couple a power connector from the output connection206to the loads118. To configure the power module200in the second configuration, the user may couple a power connector from the output connection206to the grid114.

FIG.3illustrates a schematic diagram of the power system100according to an example. As discussed above, the power system100includes the first group of power modules106and the second group of power modules108. The first group of power modules106is in the first configuration, as indicated by the output connection206of each power module of the first group of power modules106being coupled to the loads118. The second group of power modules108is in the second configuration, as indicated by the output connection206of each power module of the second group of power modules108being coupled to the grid114.

The system controller110may receive signals from the grid controller112indicative of a request for the UPS system102to provide grid services to the grid114. These services may include frequency-containment services, fast frequency response (FFR) services, power services, voltage-support services, ramping and balancing services, and other reliability services for power systems and power grids. The system controller110may alter the UPS system's102mode of operation based on the requests from the grid controller112. The system controller110may also be communicatively coupled to sensors (not shown) which allow it to determine the voltage, current, temperature, power level, and/or other operating parameters and conditions within the UPS system. The system controller110may be communicatively coupled to memory and display interfaces (not shown), and/or to the module controllers216of the plurality of power modules104. The module controllers216may also be communicatively coupled to each other.

As discussed above, the system controller110may control operation of the plurality of power modules104. In one example, the system controller110may instruct a respective module controller216to control operation of a respective power module200. In other examples, the system controller110may control components of the power module200directly. An example of controlling operation of the plurality of power modules104is provided with respect toFIG.4.

FIG.4illustrates a process400of operating the UPS system102according to an example. In various examples, the process400may be executed by the system controller110individually or in combination with one or more additional components or devices, such as at least one module controller216of one or more power modules of the plurality of power modules104. For purposes of explanation, examples are provided in which the system controller110executes one or more acts of the process400, however the process400may also be executed by the module controllers216individually and/or in tandem with one another, and/or individually and/or in tandem with the system controller110.

At act402, the process400begins. In some examples, the UPS system102may be operating in some mode of operation prior to the process400beginning at act402. In other examples, the process400may begin when the UPS system102is initially powered up. In various examples, the process400may be executed continuously and repeatedly while the UPS system102is in operation (for example, powered up).

At act404, the system controller110determines whether a request for power has been received from the grid controller112. For example, the grid controller112may request frequency-containment services from the UPS system102. The grid controller112may request power from the UPS system102to correct an imbalance between power supply available to the grid114and power demand from the grid114, for example. In other examples, the grid controller112may request power for additional or different reasons, such as to correct a deviation in frequency, or to improve a power factor of power on the grid114. If the system controller110determines that a request for power has been received from the grid controller112(404YES), then the process400continues to act406.

At act406, the system controller110controls the plurality of power modules104to operate in a reverse operating mode. For example, in the reverse operating mode, the system controller110may control the first group of power modules106to provide power derived from the backup power source116to the loads118and may control the second group of power modules108to provide power derived from the backup power source116to the grid114. An example of the reverse operating mode if provided with respect toFIG.5.

FIG.5illustrates a schematic diagram of the power system100in the reverse operating mode according to an example. Arrows may indicate a direction of power in the power system100during at least one instant in time during the reverse operating mode. The system controller110may control the first group of power modules106to draw DC power from the backup power source116, convert the DC power to AC power, and provide the AC power to the loads118.

For example, where the power module200provides an example of one of the power modules of the first group of power modules106, the system controller110may control (either directly or via the module controller216) the DC/DC converter214to draw DC power from the backup power source116via the second input204, convert the drawn DC power to converted DC power, and provide the converted DC power to the DC/AC inverter212via the power busses210, and control the DC/AC inverter212to draw the DC power from the power busses210, convert the DC power to AC power, and provide the AC power to the loads118via the output connection206.

The system controller110may also control the second group of power modules108to draw DC power from the backup power source116, convert the DC power to AC power, and provide the AC power to the grid114. For example, where the power module200provides an example of one of the power modules of the second group of power modules108, the system controller110may control (either directly or via the controller216) the DC/DC converter214to draw DC power from the backup power source116via the second input204, convert the drawn DC power to converted DC power, and provide the converted DC power to the DC/AC inverter212via the power busses210, and control the DC/AC inverter212to draw the DC power from the power busses210, convert the DC power to AC power, and provide the AC power to the grid114via the output connection206.

It will be appreciated that when the UPS system102utilizes power as described above, the UPS system102may provide a majority of the power available to the UPS system102to the loads118, the backup power source116, and/or the grid114as described above with respect to the mode of operation of the UPS system102. However, in some examples, some power may be provided to elements of the UPS system102, such as the module controllers216, the system controller110, the communication interface218, or any other elements of UPS system102that require power to operate. In some examples, the power provided to these other elements of the UPS system102may be small compared to the power provided to the loads118, the backup power source116, and/or the grid114.

The process400then proceeds to act408. At act408, the system controller110determines whether the UPS system102is receiving regenerative or backfeed power from the loads118. In various examples, the loads118may include one or more regenerative loads configured to provide regenerative power to the UPS system102. For example, the loads118may provide the regenerative power to the first group of power modules106. Each power module of the first group of power modules106may receive power at a respective output206. The system controller110may determine that the UPS system102is receiving regenerative power by determining that the first group of power modules106are receiving power at the respective outputs206.

If the system controller110determines that the UPS system102is not receiving regenerative or backfeed power form the loads118(408NO), then the process400returns to act404. However, if the system controller110determines that the UPS system102is receiving regenerative or backfeed power from the loads118(408YES), then the process400may continue to act410.

At act410, the system controller110controls the plurality of power modules104to operate in a regenerative operating mode. For example, in the regenerative operating mode, the system controller110may control the first group of power modules106to provide power derived from the loads118to the backup power source116and/or the second inputs202of the second group of power modules108. In some examples, the system controller110may control the first group of power modules106to provide the power derived from the loads118to the backup power source116or, if the backup power source116is charged, to the grid114via the second group of power modules108. The system controller110may control the second group of power modules108to provide power to the grid114. An example of the regenerative operating mode is provided with respect toFIG.6.

FIG.6illustrates a schematic diagram of the power system100in the regenerative operating mode according to an example. Arrows may indicate a direction of power in the power system100during at least one instant in time during the regenerative operating mode. However, power may be provided in one or more additional or different directions at different points in time of the regenerative operating mode. The system controller110may control the first group of power modules106to draw AC power from the loads118, convert the AC power to DC power, and provide the DC power to the backup power source116and/or the second group of power modules108.

For example, where the power module200provides an example of one of the power modules of the first group of power modules106, the system controller110may control (either directly or via the module controller216) the DC/AC inverter212to draw AC power from the loads118via the output206, convert the drawn AC power to converted DC power, and provide the converted DC power to the DC/DC converter214via the power busses210. The DC/DC converter214may provide the DC power to the backup power source116and/or the second group of power modules108via the output connections206of the first group of power modules106.

In one example, the system controller110may control (either directly or via the module controller216) the one or more power modules of the first group of power modules106to provide, via the DC/DC converter214, power to the backup power source116. For example, the first group of power modules106may provide power to the backup power source116if the backup power source116is not fully charged. In some examples, the system controller110may control (either directly or via the module controller216) the one or more power modules of the first group of power modules106to provide, via the DC/DC converter214, power to the grid114via the second group of power modules108in addition to, or in lieu of, providing power to the backup power source116. For example, the first group of power modules106may provide the power to the second group of power modules108if the backup power source116is fully charged (or charged above a threshold amount), and the second group of power modules108may provide the power to the grid114.

In examples in which the second group of power modules108provide power to the grid114, the system controller110may also control the second group of power modules108to draw DC power from the backup power source116and/or from the first group of power modules106, convert the DC power to AC power, and provide the AC power to the grid114. For example, where the power module200provides an example of one of the power modules of the second group of power modules108, the system controller110may control (either directly or via the controller216) the DC/DC converter214to draw DC power from the backup power source116and/or the first group of power modules106via the second inputs204of the second group of power modules108, convert the drawn DC power to converted DC power, and provide the converted DC power to the DC/AC inverter212via the power busses210, and control the DC/AC inverter212to draw the DC power from the power busses210, convert the DC power to AC power, and provide the AC power to the grid114via the output connection206.

It will be appreciated that when the UPS system102utilizes power as described above, the UPS system102may provide a majority of the power available to the system to the loads118, backup power source116, and/or grid114as described above with respect to the UPS system's102mode of operation. However, in some examples, some power may be provided to elements of the UPS system102, such as the module controllers216, the system controller110, the communication interface218, or any other elements of UPS system102that require power to operate. In some examples, the power provided to these other elements of the UPS system102may be small compared to the power provided to the loads118, the backup power source116, and/or the grid114.

The process400then returns to act404. If the system controller110determines that no request for power has been received from the grid controller (404NO), then the process400continues to act412.

At act412, the system controller110controls the plurality of power modules104to operate in a forward operating mode. For example, in the forward operating mode, the system controller110may control the first group of power modules106to provide power derived from the grid114to the backup power source116and/or the loads118. The system controller110may control the second group of power modules108to provide power to the backup power source116. An example of the forward operating mode is provided with respect toFIG.7.

FIG.7illustrates a schematic diagram of the power system100in the forward operating mode according to an example. Arrows may indicate a direction of power in the power system100during at least one instant in time during the forward operating mode. The system controller110may control the first group of power modules106to draw AC power from the grid114, convert the AC power to DC power, and provide the DC power to the backup power source116and/or the loads118.

For example, where the power module200provides an example of one of the power modules of the first group of power modules106, the system controller110may control (either directly or via the module controller216) the AC/DC converter208to draw AC power from the grid114via the first input202, convert the drawn AC power to converted DC power, and provide the converted DC power to the DC/DC converter214via the power busses210, and provide the DC power to the backup power source116and/or the loads118.

The system controller110may also control the second group of power modules108to draw AC power from the grid114, convert the AC power to DC power, and provide the DC power to the backup power source116. For example, where the power module200provides an example of one of the power modules of the second group of power modules108, the system controller110may control (either directly or via the controller216) the AC/DC converter208to draw AC power from the grid114first inputs202of the second group of power modules108, convert the drawn AC power to converted DC power, and provide the converted DC power to the DC/DC converter214via the power busses210, and control the DC/DC converter214to draw the DC power from the power busses210, and provide the DC power to the backup power source116via the second input204.

It will be appreciated that when the UPS system102utilizes power as described above, the UPS system102may provide a majority of the power available to the system to the loads118, backup power source116, and/or grid114as described above with respect to the UPS system's102mode of operation. However, in some examples, some power may be provided to elements of the UPS system102, such as the module controllers216, the system controller110, the communication interface218, or any other elements of UPS system102that require power to operate. In some examples, the power provided to these other elements of the UPS system102

may be small compared to the power provided to the loads118, the backup power source116, and/or the grid114.

The process400then continues to act408. As discussed above, at act408the system controller110determines whether the UPS system102is receiving regenerative or backfeed power from the loads118. If the system controller110determines that regenerative or backfeed power is available (408YES), then the process400continues to act410. Otherwise, if the system controller110determines that regenerative or backfeed power is not available (408NO), then the process400returns to act404. The process400may be repeatedly executed to select a mode of operation for the UPS system102.

It should be appreciated that these acts of the process400are purely illustrative and may occur in various orders or even simultaneously. For example, a determination as to whether a request to provide power to the grid114has been received (as discussed above with respect to act404) and a determination as to whether regenerative (backfeed) power is available (as discussed above with respect to act408) may be executed in parallel (and, in some examples, substantially simultaneously) in various examples. In various examples, determining a request to provide power to the grid114(as discussed above with respect to act404) may include one or more signals and may contain various types of information, such as control information directly instructing the UPS system102to operate in a particular operation mode and/or other information which may prompt the system to switch between operating modes. Furthermore, the modes may be executed concurrently or sequentially with each other.

In some examples, the UPS system102may be configured to operate in the regenerative operating mode (as discussed above with respect to acts408and410) for so long as regenerative power is available, and may provide the regenerative power (or power derived therefrom) to the grid114and/or the backup power source116. The UPS system102may then operate in a different operating mode, such as an operating mode that the UPS system102was in prior to entering regenerative operating mode, such as the reverse or forward operating modes. In some examples, act408may be executed before and/or in parallel with one or more acts of the process400, such as acts404,406,410and/or412. Other acts in process400may also be executed in a different order.

In some cases, the system controller110controls the operation modes of the power modules and changes between the modes of operation. In other cases, the module controllers216may control the operation mode of their respective power modules200and change between the modes of operation. In some cases, the system controller110and module controllers216may control the operation mode and changes between the operation modes of the power modules200together or in a distributed manner. For example, each of the converters208,212,214may include one or more switches. These switches may be of any appropriate type, such as transistor-based switches or relays. In some examples, the system controller110directly controls the operation of the switches. In other examples, the system controller110controls the module controllers216, and the module controllers216in turn control the switches. In other examples, the system controller110and module controllers216may both control the switches in tandem, in a distributed manner, and/or independently of each other.

It will also be appreciated that the operating modes described inFIGS.5-7may not necessarily constitute all the operating modes that the UPS system102may operate in. Other modes may exist.

It will also be appreciated that, in some examples, during the operating modes described above, power provided to the loads118may be provided as voltage-controlled power and power provided to the grid114may be provided as current-controlled power. In other examples, the power provided to the loads118, grid114, and/or backup power source116may be controlled according to one or more parameters, such as voltage, current, temperature, wattage, and so forth.

In some examples, the ratio of power modules in the first group of power modules106to the power modules in the second group of power modules108may not be one-to-one. For example, there may be more or fewer power modules in the first group of power modules106compared to in the second group of power modules108. In other examples, the first group of power modules106may include the same number of power modules as the second group of power modules108.

In some examples, one or more power modules of the plurality of power modules104may be modular. Accordingly, power modules may be added to or removed from the UPS system102and/or may be moved between the groups of power modules106,108as desired. For example, a power module may be moved from the first group of power modules106to the second group of power modules108. The power module may be moved from the first group of power modules106to the second group of power modules108, for example, disconnecting the module output206from the loads118and connecting the module output206to the grid114.

In some examples, the system controller110may be configured to control a mode of operation of each power module of the plurality of power modules104, as discussed above. However, in various examples, each power module of the plurality of power modules104may be configured to control the mode of operation in which the respective power module operates. For example, the module controller216may detect certain parameters, such as input and/or output voltage levels, input and/or output current levels, temperatures, or other parameters, and operate the power module200based on the parameters.

Various controllers, such as the system controller110, grid controller112, and/or module controller216, may execute various operations discussed above. One or more of the controllers110,112,216may be communicatively coupled to data storage devices, such as hard drives or solid state drives or other forms of computer memory. Using data stored in associated memory and/or storage, any of the controllers110,112,216may, respectively, execute one or more instructions stored on one or more respective non-transitory computer-readable media, which the respective controller may include and/or be coupled to, which may result in manipulated data. In some examples, one or more of the controllers110,112,216may include one or more processors or other types of controllers. In one example, the system controller110and/or module controller216is or includes at least one processor. In another example, the controllers110,112,216may perform at least a portion of the operations discussed above using an application-specific integrated circuit tailored to perform particular operations in addition to, or in lieu of, a general-purpose processor. As illustrated by these examples, examples in accordance with the present disclosure may perform the operations described herein using many specific combinations of hardware and software and the disclosure is not limited to any particular combination of hardware and software components. Examples of the disclosure may include a computer-program product configured to execute methods, processes, and/or operations discussed above. The computer-program product may be, or include, one or more controllers and/or processors configured to execute instructions to perform methods, processes, and/or operations discussed above.

Having thus described several aspects of at least one embodiment, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of, and within the spirit and scope of, this disclosure. Accordingly, the foregoing description and drawings are by way of example only.