High reliability modular welding power supply system

Embodiments of modular-based power supply systems to support welding or cutting operations are disclosed. One embodiment includes a module rack having multiple slots configured to accept electrical input power from a single power drop within a welding or cutting environment. Multiple power supply modules are provided that are configured to be inserted into and withdrawn from the multiple slots. Each power supply module is configured to accept an electrical AC input derived from the electrical input power and provide an electrical DC output. The module rack is configured to support reconfigurable parallel electrical connections of subsets of the power supply modules. Each subset is configured to electrically connect to an output power supply stage to provide a dynamic waveform-controlled welding or cutting electrical signal to support generation of a single arc between an electrode and a workpiece.

CROSS REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE

U.S. Patent Application No. 2015/0014290 A1 entitled “Welding System and Method of Welding”, filed on Oct. 2, 2014, is incorporated herein by reference in its entirety.

FIELD

Embodiments of the present invention relate to systems associated with a welding or cutting environment. More specifically, embodiments of the present invention relate to reconfigurable systems for generating one or more arcs for welding or cutting.

BACKGROUND

In a welding or cutting environment (e.g., in a factory environment where welding or cutting is performed), many welding or cutting power supplies may be located at various locations within the welding or cutting environment to support various welding or cutting operations throughout the environment. When a power supply has a problem and shuts down, the corresponding welding or cutting operation is also shut down until the problem can be resolved. The ability to have a power supply configuration that allows the corresponding welding or cutting operation to continue, even while the problem is being resolved, is desirable.

SUMMARY

Embodiments of the present invention include systems to support the generation of one or more (multiple) arcs for welding or plasma cutting in a welding or cutting environment (e.g., a factory). A reconfigurable modular power supply system provides redundancy, improved reliability, improved up-time, and improved serviceability across the welding or cutting environment. Such improvements are achieved by the implementation of hot-swappable power supply modules in a reconfigurable module rack. As used herein, power supply modules that are hot-swappable are power supply modules that can be removed from and inserted into a module rack without stopping or shutting down the associated welding or cutting system (i.e., without interruption to the on-going welding or cutting operation). Hot-swapping can be achieved by rack and module design particulars as well as by employing a controller implementing hot-swapping control techniques, as discussed later herein.

One embodiment includes a system to support the generation of multiple arcs for welding or cutting within a welding or cutting environment. The system includes a module rack having a plurality of module slots. The module rack is configured to accept electrical input power from a single power drop within the welding or cutting environment via a power disconnect box. The system also includes a plurality of power supply modules (e.g., hot-swappable power supply modules) configured to be respectively inserted into and withdrawn from the plurality of module slots. Each power supply module is configured to accept an electrical AC input derived from the electrical input power and provide an electrical DC output. The module rack is configured to support reconfigurable parallel electrical connections of subsets of the power supply modules inserted into the module rack. The system further includes a plurality of output power supply stages. An electrical input of each output power supply stage is configured to connect to an electrical output of a separate subset of the subsets of the power supply modules. Each output power supply stage is configured to provide a dynamic waveform-controlled welding or cutting electrical signal to support the generation of a single arc, of the multiple arcs, between an electrode and a workpiece for welding or cutting. The system also includes a controller operatively interfacing to the module rack, in one embodiment. The controller is configured to define and electrically connect in parallel a first subset of the power supply modules within the module rack. The controller is also configured to electrically connect a newly inserted power supply module into the first subset while avoiding generating electrical surges within the module rack, and while avoiding generating disturbances in a first welding or cutting electrical signal associated with the first subset during a first welding or cutting operation. In one embodiment, each power supply module includes a first power supply stage and a second power supply stage. In one embodiment, each power supply module includes an AC to DC converter circuit. In one embodiment, each power supply module includes an unregulated DC to DC converter circuit. In one embodiment, each power supply module includes an inverter circuit with an isolation transformer and a rectifier circuit. In one embodiment, each output power supply stage includes a chopper circuit. In one embodiment, each output power supply stage is configured to be located remotely from the module rack and be electrically connected to the module rack via an electrical cable. In another embodiment, each output power supply stage is configured to be located within the module rack.

One embodiment includes a system to support the generation of multiple arcs for welding or cutting within a welding or cutting environment. The system includes a module rack having a plurality of module slots. The module rack is configured to accept electrical input power from a single power drop within the welding or cutting environment via a power disconnect box. The system also includes a plurality of power supply modules (e.g., hot-swappable power supply modules) configured to be respectively inserted into and withdrawn from the plurality of module slots. Each power supply module is configured to accept an electrical AC input derived from the electrical input power and provide an electrical DC output. Each power supply module is also configured to provide a dynamic waveform-controlled output signal. The module rack is configured to support reconfigurable parallel electrical connections of subsets of the power supply modules inserted into the module rack. The system also includes a controller operatively interfacing to the module rack and configured to synchronize the dynamic waveform-controlled output signal of each power supply module, within each subset, with each other to provide a welding or cutting electrical signal from each subset. Synchronization of the dynamic waveform-controlled output signals of each subset is based on feedback information from each corresponding subset, in accordance with one embodiment. The welding or cutting electrical signal from each subset supports generation of a single arc, of the multiple arcs, between an electrode and a workpiece for welding or cutting. In one embodiment, the controller is configured to define and electrically connect in parallel a first subset of the power supply modules within the module rack. The controller is also configured to electrically connect a newly inserted power supply module into the first subset while avoiding generating electrical surges within the module rack, and while avoiding generating disturbances in a first welding or cutting electrical signal associated with the first subset during a first welding or cutting operation. In one embodiment, the controller is configured to report a failure of a power supply module to an external reporting system. In one embodiment, each power supply module includes a first power supply stage, a second power supply stage, and a third power supply stage. In one embodiment, each power supply module includes an AC to DC converter circuit. In one embodiment, each power supply module includes an unregulated DC to DC converter circuit. In one embodiment, each power supply module includes an inverter circuit with an isolation transformer and a rectifier circuit. In one embodiment, each power supply module includes a chopper circuit.

One embodiment includes a system to support the generation of at least one arc for welding or cutting within a welding or cutting environment. The system includes a module rack having a plurality of module slots. The module rack is configured to accept electrical input power from a single power drop within a welding or cutting environment via a power disconnect box. The system includes a plurality of power supply modules (e.g., hot-swappable power supply modules) configured to be respectively inserted into and withdrawn from the plurality of module slots. The module rack is configured to support reconfigurable parallel electrical connections of the plurality of power supply modules inserted into the module rack. The system further includes a controller configured to electrically connect a newly replaced power supply module within the module rack while avoiding generating electrical surges within the module rack, and while avoiding generating disturbances in a welding or cutting electrical signal supported by the module rack during a welding or cutting operation. In one embodiment, the controller is configured to report a failure of a power supply module to an external reporting system.

Numerous aspects of the general inventive concepts will become readily apparent from the following detailed description of exemplary embodiments, from the claims, and from the accompanying drawings.

DETAILED DESCRIPTION

Embodiments of reconfigurable systems to support the generation of one or more arcs for welding or cutting in a welding or cutting environment are disclosed. In one embodiment, a reconfigurable multi-arc system is disclosed. The reconfigurable multi-arc system includes a module rack and multiple power supply modules (e.g., hot-swappable power supply modules) organized within the module rack to support the generation of multiple arcs for welding or cutting within a welding or cutting environment.

The examples and figures herein are illustrative only and are not meant to limit the subject invention, which is measured by the scope and spirit of the claims. Referring now to the drawings, wherein the showings are for the purpose of illustrating exemplary embodiments of the subject invention only and not for the purpose of limiting same,FIG. 1illustrates a first embodiment of a reconfigurable multi-arc system100to support the generation of multiple arcs for welding or plasma cutting in a welding or cutting environment.

Referring toFIG. 1, the reconfigurable multi-arc system100includes a module rack110having multiple module slots115. Each module slot115is configured to have a power supply module inserted into and withdrawn from a slot in a hot-swappable manner. The power supply modules can support one or more welding or cutting operations. The power supply modules are hot-swappable and can be removed from and inserted into the module rack110without stopping or shutting down the associated welding or cutting system (i.e., without interruption to an on-going welding or cutting operation). Hot-swapping can be achieved by rack and module design particulars as well as by employing a controller implementing hot-swapping control techniques. An embodiment of a power supply module is discussed later herein with respect toFIG. 2. In another embodiment, the power supply modules are not hot-swappable.

In accordance with one embodiment, the module rack110includes wiring and/or traces and controllable switches that support reconfigurable electrical connections of the power supply modules. For example, the module rack110may include a reconfigurable backplane that allows various combinations or subsets of power supply modules to be electrically connected to each other. The reconfigurable backplane may be under the control of a programmable controller, for example, in accordance with one embodiment. Furthermore, in one embodiment, the module rack110is configured to accept electrical input power (e.g., 460 VAC) from a single power drop within a welding or cutting environment via, for example, a power disconnect box having, for example, switches and fuses. Electrical power distributed to the inputs of individual power supply modules within the module rack110is derived from the electrical input power (e.g., under the control of a controller).

The system100includes a controller120operatively interfacing to the module rack110. In one embodiment, the controller120is configured to define subsets of the power supply modules within the module rack110. The controller120is also configured to command electrical connection of a defined subset of the power supply modules in parallel via the module rack (e.g. by reconfiguring a backplane of the module rack110). Such a subset of power supply modules can be used in a welding or cutting operation to support generation of a single arc between an electrode and a workpiece for welding or cutting in a welding or cutting environment. In such an embodiment, the controller120provides flexibility in defining a subset of power supply modules within the module rack110to be electrically connected together in parallel. In the extreme, a subset can include a single power supply module. Redundancy can be provided by having the total power supplied by the multiple power supply modules within the module rack110be more than the total output power requirement from the module rack110. Furthermore, in accordance with one embodiment, the controller120is configured to reduce the output power when some of the power supply modules are down.

The controller120is also configured to electrically connect a newly inserted hot-swappable power supply module into a subset while avoiding generating electrical surges within the module rack110, and while avoiding generating disturbances in a welding or cutting electrical signal associated with the subset during a welding or cutting operation. In accordance with one embodiment, the controller120can avoid the occurrence of such surges and disturbances by bringing a newly inserted power supply module on-line slowly (e.g., by slowly powering up the newly inserted power supply module) and/or by electrically connecting various input and output pins of the newly inserted power supply module in a particular order. The controller is configured to balance the power draw from each module by ramping up the power of a newly inserted module and ramping down the power of existing on-line modules, in accordance with one embodiment.

In another embodiment, the subsets of power supply modules are defined largely by the module rack110. For example, referring toFIG. 1, five (5) rows of slots115are shown within the module rack110which can be populated with hot-swappable power supply modules. The first row defines a first subset corresponding to up to ten (10) modules. Similarly, the second through fifth rows each define subsets corresponding to, respectively, up to ten (10), nine (9), eight (8), and seven (7) modules. In such an embodiment, the controller120is still used to support hot-swapping of the power supply modules to avoid surges and disturbances.

As shown inFIG. 1, each subset (row) of slots115, which may be populated with hot-swappable power supply modules, can be electrically connected to a chopper circuit130serving as an output power supply stage. Other types of output power supply stages (other than a chopper circuit) are possible as well, in accordance with other embodiments. An electrical input of each output power supply stage130is configured to be connected to an electrical output of a separate subset of the hot-swappable power supply modules that are connected in parallel.

Each output power supply stage130provides a dynamic waveform-controlled welding or cutting signal to support generation of a single arc between an electrode and a workpiece for welding or cutting. For example, a dynamic waveform-controlled welding or cutting signal from an output power supply stage130may be provided to a welding gun/torch and/or welding wire feeder within a welding or cutting environment. In this manner, the system100ofFIG. 1provides the dynamic welding or cutting voltages and currents to support various welding or cutting operations and modes. In accordance with one embodiment, each output power supply stage130(e.g., chopper circuit) is under the control of a separate controller and/or a waveform generator. U.S. Patent Application No. 2015/0014290 A1, which is incorporated by reference herein, describes various configurations of output power supply stages that are controlled by a controller and/or a waveform generator.

FIG. 2illustrates a first embodiment of a hot-swappable power supply module200that may be used in the systems100,300,400, and500ofFIG. 1,FIG. 3,FIG. 4, andFIG. 5, respectively. The hot-swappable power supply module200is configured to be inserted into and withdrawn from, for example, any of the slots115in the module rack110in a hot-swappable manner. The hot-swappable power supply module200includes an electrical input connector210, a first power supply stage220, a second power supply stage230, and an electrical output connector240.

The electrical input connector210is configured to accept electrical input power (e.g., AC input power). In one embodiment, the electrical input connector210is also configured to accept one or more control signals from a controller (e.g., from the controller120via a backplane of the module rack110). The one or more control signals control the operations of the first power supply stage220and the second power supply stage230, in accordance with one embodiment. U.S. Patent Application No. 2015/0014290 A1, which is incorporated by reference herein, describes various types of first (I) and second (II) power supply stages that are controlled by a controller. The electrical output connector240is configured to output an unregulated electrical DC signal. In one embodiment, the electrical output connector240is also configured to output one or more feedback signals to a controller (e.g., to the controller120via a backplane of the module rack110). The feedback signals may be derived from, for example, an output voltage and/or an output current of the module200, in accordance with one embodiment, which are used by the controller120to modify the control signals.

The feedback signals can also include module status signals. For example, a feedback signal can indicate when a particular module has failed (or has gone off-line). The controller can use the feedback information to report the failure to, for example, an external reporting system. As a result, a service call can be initiated to replace the failed module. Furthermore, the controller can use the feedback information to take the failed module off-line and bring another module on-line in its place within the associated subset of modules. In this manner, the operation (e.g., power, waveform, timing) and the status (e.g., failed module) of each power supply module can be monitored and controlled, and power supply modules can be taken off-line and brought on-line in a real-time, dynamic manner.

In one embodiment, the first power supply stage220is an AC to DC converter circuit. The second power supply stage230is an unregulated DC to DC converter circuit. For example, in one embodiment, the second power supply stage230may include an inverter circuit with an isolation transformer and a rectifier circuit. The first power supply stage220accepts an electrical AC input signal, derived from the electrical input power to the module rack110, at the electrical input connector210. The second power supply stage230outputs an electrical DC output signal at the electrical output connector240. Providing an electrical AC input to the module200is facilitated by a backplane of the module rack110, in accordance with one embodiment. Also, routing the electrical DC output signal away from the electrical output connector240is facilitated by the backplane of the module rack110, in accordance with one embodiment. In accordance with one embodiment, The AC to DC converter circuit of the first power supply stage220is configured to provide a power factor correction function.

U.S. Patent Application No. 2015/0014290 A1, which is incorporated by reference herein, describes various types of first (I) and second (II) power supply stages. Other types of hot-swappable power supply modules are possible as well, in accordance with other embodiments. For example, in one embodiment, a hot-swappable power supply module may have a single stage. In another embodiment, a hot-swappable power supply module may have three stages. The numbers and types of stages depend on the design considerations and constraints associated with any particular application.

In accordance with one embodiment, each hot-swappable power supply module200provides 50 amps of electrical current. Therefore, a subset of such hot-swappable power supply modules200electrically connected in parallel can provide an electrical current of N×50 amps, where N is the number of power supply modules200connected in parallel. Therefore, depending on the current need for a particular welding or cutting operation, the controller120can select the number N of power supply modules200to be electrically connected and used for that operation. In accordance with other embodiments, each hot-swappable power supply module200provides some other amount of electrical current (e.g. 25 amps, or 75 amps, or 100 amps).

In the embodiment ofFIG. 1, each output power supply stage130(e.g., a chopper circuit) is external to the module rack110. For example, in accordance with one embodiment, the module rack110is centrally located within a welding or cutting environment, accepting electrical input power from a single power drop via a power disconnect box. Each chopper circuit130is located remotely from the module rack110at a robotic welding or cutting station within the welding or cutting environment and is electrically connected to the module rack110via electrical cables. In this way, a single module rack110can support the generation of multiple welding or cutting arcs throughout the welding or cutting environment. The DC outputs out of the module rack110are not affected by the inductance of the electrical cables connecting the module rack110to the various chopper circuits130at the welding or cutting stations. Therefore, fairly long cable lengths can be accommodated across a welding or cutting environment.

FIG. 3illustrates a second embodiment of a reconfigurable multi-arc system300to support the generation of multiple arcs for welding or cutting in a welding or cutting environment. The system300ofFIG. 3is similar to the system100ofFIG. 1in that the system300includes a module rack310having module slots315(similar to the module slots115to accept the modules200), a controller320(similar to the controller120), and output power supply stages (e.g., chopper circuits)330(similar to the output power supply stages130). However, in the system300ofFIG. 3, the output power supply stages (e.g., chopper circuits)330are located within the module rack310, not externally to the module rack310. In one embodiment, the controller320can determine which chopper circuit330to connect to which subset of hot-swappable power supply modules via, for example, a backplane of the module rack310. Furthermore, in accordance with one embodiment, the controller320also controls the operation of each of the output power supply stages330. In accordance with another embodiment, each output power supply stage330may be controlled by a dedicated controller within the module rack310. The system300ofFIG. 3may be desirable when used in a welding or cutting environment that is relatively small, mitigating the use of long cable lengths to the welding or cutting stations.

FIG. 4illustrates a first embodiment of a reconfigurable single-arc system400to support the generation of a single arc for welding or cutting in a welding or cutting environment. The system400includes a module rack410having module slots415to accommodate hot-swappable power supply modules (e.g.,200). The system also includes a controller420and an output power supply stage (e.g., a chopper circuit)430. The system400is similar to a portion of the system100ofFIG. 1. For example, the module rack410may be equivalent to the first row of the module rack110inFIG. 1. The chopper circuit430may be equivalent to the chopper #1130inFIG. 1. The controller420may be somewhat similar to the controller120inFIG. 1. However, in the system400ofFIG. 4, only the generation of a single arc is supported (e.g., at a robotic welding or cutting work station or at a manual welding or cutting work station) within a welding or cutting environment.

In the embodiment ofFIG. 4, the controller420determines which power supply modules to use to provide an electrical input to the chopper circuit430. The controller420also allows the power supply modules to be replaced in the slots415in a hot-swappable manner. Furthermore, in accordance with one embodiment, the controller420controls the operation of the chopper circuit430. For example, in one embodiment, the controller420includes a waveform generator to facilitate the generation of a dynamic waveform-controlled welding or cutting electrical signal by the chopper circuit430. Examples of controlling a chopper circuit via a waveform generator are disclosed in U.S. Patent Application No. 2015/0014290 A1, which is incorporated by reference herein. In this manner, a smaller module rack can be provided to support a single arc operation. Also, the DC output out of the module rack410is not affected by the inductance of the electrical cable connecting the module rack410to the chopper circuit430at the welding or cutting station. Therefore, a fairly long cable length can be accommodated.

FIG. 5illustrates a second embodiment of a reconfigurable single-arc system500to support the generation of a single arc for welding or cutting in a welding or cutting environment. The system500is similar to the system400ofFIG. 4in that the system500includes a module rack510having module slots515(similar to the module slots415to accept the modules200), a controller520(similar to the controller420), and an output power supply stage (e.g., a chopper circuit)530(similar to the output power supply stage430). However, in the system500ofFIG. 5, the output power supply stage (e.g., the chopper circuit)530is located within the module rack510, not externally to the module rack510. In one embodiment, the controller520determines which power supply modules to use to provide an electrical input to the chopper circuit530. The controller520also allows the power supply modules to be replaced in the slots515in a hot-swappable manner. Furthermore, in accordance with one embodiment, the controller520controls the operation of the chopper circuit530. The system500ofFIG. 5may be desirable when used in a welding or cutting environment that is relatively small, mitigating the use of a long cable length to the welding or cutting station. In this manner, a smaller module rack can be provided to support a single arc operation.

FIG. 6illustrates a third embodiment of a reconfigurable multi-arc system600to support the generation of multiple arcs for welding or cutting in a welding or cutting environment. In the embodiment ofFIG. 6, an output power supply stage is part of each hot-swappable power supply module. The dynamic waveform-controlled output signals generated by the output power supply stages of the hot-swappable power supply modules in a defined subset are synchronized and combined to generate a total welding or cutting electrical signal for welding or cutting.

The reconfigurable multi-arc system600includes a module rack610having multiple module slots615. Each module slot615is configured to have a power supply module (which includes an output power supply stage) inserted into and withdrawn from a slot in a hot-swappable manner. The power supply modules can support one or more welding or cutting operations. The power supply modules are hot-swappable and can be removed from and inserted into the module rack610without stopping or shutting down the associated welding or cutting system (i.e., without interruption to an on-going welding or cutting operation). Hot-swapping can be achieved by rack and module design particulars as well as by employing a controller implementing hot-swapping control techniques. An embodiment of a power supply module is discussed later herein with respect toFIG. 7.

In accordance with one embodiment, the module rack610includes wiring and/or traces and controllable switches that support reconfigurable electrical connections of the power supply modules. For example, the module rack610may include a reconfigurable backplane that allows various combinations or subsets of power supply modules to be electrically connected to each other. The reconfigurable backplane may be under the control of a programmable controller, for example. Furthermore, in one embodiment, the module rack610is configured to accept electrical input power (e.g., 460 VAC) from a single power drop within a welding or cutting environment via, for example, a power disconnect box having, for example, switches and fuses. Electrical power distributed to the inputs of individual power supply modules within the module rack610is derived from the electrical input power (e.g., under the control of a controller).

The system600includes a controller620operatively interfacing to the module rack610. In one embodiment, the controller620is configured to define subsets of the power supply modules within the module rack610. The controller620is also configured to command electrical connection of a defined subset of the power supply modules in parallel via the module rack610(e.g. by reconfiguring a backplane of the module rack610). Such a subset of power supply modules can be used in a welding or cutting operation to support generation of a single arc between an electrode and a workpiece for welding or cutting in a welding or cutting environment. In such an embodiment, the controller620provides flexibility in defining a subset of power supply modules within the module rack610to be electrically connected together in parallel.

Each power supply module is configured to output a dynamic waveform-controlled output signal, in accordance with one embodiment. For a subset of the power supply modules, the controller620is configured to not only electrically connect the power supply modules in the subset together in parallel, but also to synchronize the dynamic waveform-controlled output signals of all the power supply modules in the subset to provide a total welding or cutting electrical signal that supports generation of an arc for welding or cutting. Details of the synchronization are discussed later herein with respect toFIG. 7.

The controller620is also configured to electrically connect a newly inserted hot-swappable power supply module into a subset while avoiding generating electrical surges within the module rack610, and while avoiding generating disturbances in a welding or cutting electrical signal associated with the subset during a welding or cutting operation. In accordance with one embodiment, the controller620can avoid the occurrence of such surges and disturbances by bringing a newly inserted power supply module on-line slowly (e.g., by slowly powering up the newly inserted power supply module) and/or by electrically connecting various input and output pins of the newly inserted power supply module in a particular order.

In another embodiment, the subsets of power supply modules are defined largely by the module rack610. For example, referring toFIG. 6, five (5) rows of slots615are shown within the module rack610which can be populated with hot-swappable power supply modules. The first row defines a first subset corresponding to up to ten (10) modules. Similarly, the second through fifth rows each define subsets corresponding to, respectively, up to ten (10), nine (9), eight (8), and seven (7) modules. In such an embodiment, the controller620is still used to support hot-swapping of the power supply modules to avoid surges and disturbances.

Each hot-swappable power supply module provides a dynamic waveform-controlled output signal. The outputs of the hot-swappable power supply modules within a defined subset are synchronized and electrically connected in parallel to form a total welding or cutting electrical signal to support generation of a single arc between an electrode and a workpiece for welding or cutting. For example, a total welding or cutting electrical signal from a subset of synchronized modules may be provided to a welding gun/torch and/or welding wire feeder within a welding or cutting environment. In this manner, the system600ofFIG. 6provides the dynamic welding or cutting voltages and currents to support various welding or cutting operations and modes. In accordance with one embodiment, each defined subset of power supply modules is under the control of the controller620to perform waveform generation.

FIG. 7illustrates a second embodiment of a hot-swappable power supply module700that may be used in the system600ofFIG. 6. The hot-swappable power supply module700is configured to be inserted into and withdrawn from, for example, any of the slots615in the module rack610in a hot-swappable manner. The hot-swappable power supply module700includes an electrical input connector710, a first power supply stage720, a second power supply stage730, a third power supply stage740, and an electrical output connector750. In the embodiment ofFIG. 7, the third power supply stage740is an output power supply stage providing a dynamic waveform-controlled output signal. The dynamic waveform-controlled output signals generated by the third power supply stages740of the hot-swappable power supply modules700in a defined subset are synchronized and combined to generate a total welding or cutting electrical signal for welding or cutting.

The electrical input connector710is configured to accept electrical input power (e.g., AC input power). In one embodiment, the electrical input connector710is also configured to accept one or more control signals from a controller (e.g., from the controller620via a backplane of the module rack610). The one or more control signals control the operations of the first power supply stage720, the second power supply stage730, and the third power supply stage740, in accordance with one embodiment. U.S. Patent Application No. 2015/0014290 A1, which is incorporated by reference herein, describes various types of first (I), second (II), and third (III) power supply stages that are controlled by a controller.

The electrical output connector750is configured to output a dynamic waveform-controlled output signal. In one embodiment, the electrical output connector750is also configured to output one or more feedback signals to a controller (e.g., to the controller620via a backplane). The feedback signals may be derived from, for example, an output voltage and/or an output current of the module700, in accordance with one embodiment, which are used by the controller620to modify the control signals. The feedback signals may also include module status signals. For example, a feedback signal may indicate when a particular module has failed (or has gone off-line). The controller can use the feedback information to report the failure to, for example, an external reporting system. As a result, a service call may be initiated to replace the failed module. In this manner, operation (e.g., power, waveform, timing) and status (e.g., failed module) of each power supply module can be monitored and controlled. Furthermore, in accordance with one embodiment, the feedback signals are used to modify the control signals to synchronize the outputs (i.e., the dynamic waveform-controlled output signals) of all of the active power supply modules700within a subset. Synchronization may be achieved by adjusting the timing of the outputs of the modules700with respect to each other, for example. The synchronized outputs, when combined, form a total welding or cutting electrical signal that supports generation of a single arc.

In one embodiment, the first power supply stage720is an AC to DC converter circuit. The second power supply stage730is an unregulated DC to DC converter circuit. The third power supply stage740includes a chopper circuit. For example, in one embodiment, the second power supply stage may include an inverter circuit with an isolation transformer and a rectifier circuit. The first power supply stage720accepts an electrical AC input signal, derived from the electrical input power to the module rack610, at the electrical input connector710. The second power supply stage730outputs an electrical DC signal to the third power supply stage740. The third power supply stage740outputs a dynamic waveform-controlled output signal at the electrical output connector750. Providing an electrical AC input to the module700is facilitated by a backplane of the module rack610, in accordance with one embodiment. Also, synchronizing and combining the dynamic waveform-controlled output signals from the electrical output connectors750is facilitated by the backplane of the module rack610, in accordance with one embodiment.

U.S. Patent Application No. 2015/0014290 A1, which is incorporated by reference herein, describes various types of first (I), second (II), and third (III) power supply stages. Other types of hot-swappable power supply modules are possible as well, in accordance with other embodiments. For example, in one embodiment, a hot-swappable power supply module may have a single stage. In another embodiment, a hot-swappable power supply module may have four stages. The numbers and types of stages depend on the design considerations and constraints associated with any particular application.

In accordance with one embodiment, each hot-swappable power supply module700provides 50 amps of electrical current. Therefore, a subset of such hot-swappable power supply modules700electrically connected in parallel can provide an electrical current of N×50 amps, where N is the number of power supply modules700synchronized and connected in parallel. Therefore, depending on the current need for a particular welding or cutting operation, the controller620can select the number N of power supply modules700to be electrically connected and used for that operation. In accordance with other embodiments, each hot-swappable power supply module700provides some other amount of electrical current (e.g. 30 amps, or 60 amps, or 90 amps).

FIG. 8illustrates an embodiment of an example controller800that may be used as the controller120,320,420,520, or620respectively in the systems100,300,400,500, and600ofFIG. 1,FIG. 3,FIG. 4,FIG. 5, andFIG. 6. The controller800includes at least one processor814which communicates with a number of peripheral devices via bus subsystem812. These peripheral devices may include a storage subsystem824, including, for example, a memory subsystem828and a file storage subsystem826, user interface input devices822, user interface output devices820, and a network interface subsystem816. The input and output devices allow user interaction with the controller800. Network interface subsystem816provides an interface to outside networks and is coupled to corresponding interface devices in other computer systems. For example, the module rack110of the system100may share one or more characteristics with the controller800and may include, for example, elements of a conventional computer, a digital signal processor, and/or other computing device.

Storage subsystem824stores programming and data constructs that provide some or all of the controller functionality described herein. For example, the storage subsystem824may include one or more software modules including computer executable instructions for electrically connecting, in a hot-swappable manner, a power supply module that is newly inserted into a module rack without generating any electrical surges within the module rack and without generating any disturbances in a welding or cutting electrical signal during a welding or cutting operation.

These software modules are generally executed by processor814alone or in combination with other processors. Memory subsystem828used in the storage subsystem can include a number of memories including a main random access memory (RAM)830for storage of instructions and data during program execution and a read only memory (ROM)832in which fixed instructions are stored. A file storage subsystem826can provide persistent storage for program and data files, and may include a hard disk drive, a floppy disk drive along with associated removable media, a CD-ROM drive, an optical drive, or removable media cartridges. The modules implementing the functionality of certain embodiments may be stored by file storage subsystem826in the storage subsystem824, or in other machines accessible by the processor(s)814.

Bus subsystem812provides a mechanism for letting the various components and subsystems of the controller800communicate with each other as intended. Although bus subsystem812is shown schematically as a single bus, alternative embodiments of the bus subsystem may use multiple buses.

The controller800can be of various implementations including a single computer, a single workstation, a computing cluster, a server computer, or any other data processing system or computing device configured to perform the controller functions described herein. Due to the ever-changing nature of computing devices and networks, the description of the controller800depicted inFIG. 8is intended only as a specific example for purposes of illustrating some embodiments. Many other configurations of the controller800are possible having more or fewer components than the controller depicted inFIG. 8.

In accordance with one embodiment, each individual power supply module that is connected in parallel is configured to produce an output that has voltage droop such that the current loads are balanced without requiring a master controller to balance the loads. The voltage droop is proportional to the load drawn such that when power supply modules are connected in parallel, the output current load is shared among the power supply modules. Furthermore, each individual power supply module is configured to ramp up an output gradually such that the other power supply modules individually compensate their loads without interfering with the total load. When one of the power supply modules attempts to provide more current, an output voltage of that power supply will droop and the other power supply modules that are in parallel will provide balance. In this manner, the controller is effectively distributed among the different power supply modules.

For example, in accordance with one embodiment, power supply modules connected in parallel are configured to share the load current by trimming the no-load output voltage difference to be substantially less than the voltage droop at full load. In another embodiment, power supply modules are configured to share the load current by increasing the output voltage droop of each power supply module such that the voltage droop at full load is substantially larger than the no-load voltage mismatch between modules. The output voltage droop is internally adjusted, for example, by adjusting an internal reference voltage based upon the load current.

In summary, a reconfigurable modular power supply system provides redundancy, improved reliability, improved up-time, and improved serviceability across the welding or cutting environment. Such improvements are achieved by the implementation of multiple power supply modules (e.g., hot-swappable power supply modules) in a reconfigurable module rack.

While the disclosed embodiments have been illustrated and described in considerable detail, it is not the intention to restrict or in any way limit the scope of the appended claims to such detail. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the various aspects of the subject matter. Therefore, the disclosure is not limited to the specific details or illustrative examples shown and described. Thus, this disclosure is intended to embrace alterations, modifications, and variations that fall within the scope of the appended claims, which satisfy the statutory subject matter requirements of 35 U.S.C. § 101. The above description of specific embodiments has been given by way of example. From the disclosure given, those skilled in the art will not only understand the general inventive concepts and attendant advantages, but will also find apparent various changes and modifications to the structures and methods disclosed. It is sought, therefore, to cover all such changes and modifications as fall within the spirit and scope of the general inventive concepts, as defined by the appended claims, and equivalents thereof.