The present invention relates to electronic devices, and more particularly, to power conversion modules.
A power conversion device, such as an uninterruptible power supply (UPS), may include multiple power conversion circuits. For example, an online UPS may include a rectifier that is used to rectify an input AC voltage to generate a DC voltage and an inverter that generates an AC voltage from this DC voltage. The UPS may also include additional power conversion circuits, such as battery charger and/or converter circuits.
Such power conversion circuits often use common components. For example, the rectifier and inverter circuits of an online UPS may use substantially similar insulated gate bipolar transistor (IGBT) half-bridge circuits. Packaged multi-transistor devices have been developed for such applications. For example, “six pack” devices are offered that include three IGBT half-bridges mounted on a common heat sink and encased in a molded housing. Passive devices, such as inductors or capacitors, may be coupled to pins of such a device to form a rectifier, inverter, or other power conversion circuit.
In some embodiments of the invention, a power conversion module includes a frame. The module also includes first external connection terminals supported by the frame, and at least four half-bridge circuits supported by the frame and electrically coupled between selected pairs of the first external connection terminals. The module further includes respective second external connection terminals supported by the frame and electrically coupled to respective center nodes of respective ones of the at least four half-bridge circuits. The module may also include at least four inductors supported by the frame, respective ones of the at least four inductors coupling respective ones of the center nodes of the at least four half-bridge circuits to respective ones of the second external connection terminals. The module may further include at least one storage capacitor supported by the frame and electrically coupled between a pair of the first external connection terminals. The at least four half-bridge circuits may include respective pairs of insulated gate bipolar transistors (IGBTs), and the module may further include respective third external connection terminals electrically coupled to gate terminals of the respective IGBTs. Such a module may be configurable to serve in a plurality of different power conversion circuit configurations, for example, a rectifier configuration or an inverter configuration.
According to further embodiments of the invention, a power conversion module includes a frame and first external connection terminals supported by the frame. The module further includes at least four half-bridge circuits supported by the frame and coupled between selected pairs of the first external connection terminals. The module also includes respective second external connection terminals supported by the frame, at least four inductors supported by the frame and coupling respective center nodes of respective ones of the at least four half-bridge circuits to respective ones of the second external connection terminals, and at least one storage capacitor supported by the frame and electrically coupled between a pair of the first external connection terminals.
In some embodiments of the invention, the frame may include a sheet metal chassis configured to provide a channel, a heat sink mounted in the channel, and a printed circuit board mounted on a surface of the chassis opposite the channel. The at least four half-bridge circuits may be mounted on the printed circuit board and may include switching devices, e.g., IGBTs, that contact the heat sink. The at least four inductors may be mounted within the channel and electrically coupled to the printed circuit board. The at least one storage capacitor may be mounted on the printed circuit board and may extend into the channel through an opening in the chassis.
According to further embodiments of the invention, a UPS includes at least two power conversion modules. Each of the modules includes a frame, first external connection terminals supported by the frame, at least four half-bridge circuits supported by the frame and electrically coupled between selected pairs of the first external connection terminals, and respective second external connection terminals supported by the frame and electrically coupled to respective center nodes of respective ones of the at least four half bridge circuits. Each of the first and second modules may also include at least four inductors supported by the frame and coupling respective ones of the center nodes of the at least four half-bridge circuits to respective ones of the second external connection terminals. Each of the first and second modules may further include at least one storage capacitor supported by the frame and electrically coupled between a pair of the first external connection terminals. The first and second modules may be configured, for example, to provide respective rectifier and inverter functions.
In some embodiments of the invention, a first set of the first external connection terminals of the first module is part of a first DC bus and a second set of the first external connection terminals of the first module is part of a second DC bus such the at least four half-bridge circuits of the first module are coupled between the first and second DC busses. The first inductors of the first module are configured to be coupled to respective phases of an AC bus, and at least one second inductor of the first module is configured to be coupled to a DC power source.
In further embodiments of the invention, a first set of the first external connection terminals of the first module is part of a first DC bus and a second set of the first external connection terminals of the first module are part of a second DC bus such that a first set of the at least four half-bridge circuits of the first module is coupled between the first and second DC busses. At least one of the first external connection terminals of the first module is configured to be coupled to a DC power source such that at least one of the at least four half-bridge circuits of the first modules is configured to be coupled between the second DC bus and the DC power source. The first inductors of the first module are configured to be coupled to respective phases of an AC bus, and at least one second inductor of the first module is configured to be coupled to the first DC bus.
In some embodiments of the invention, a first set of the first external connection terminals of the second module are part of a first DC bus and a second set of the first external connection terminals of the second module is part of a second DC bus such the at least four half-bridge circuits of the first module are coupled between the first and second DC busses. First inductors of the second module are configured to be coupled to respective phases of an AC bus, and at least one second inductor of the second module is configured to be coupled to a neutral of the AC bus.
Specific exemplary embodiments of the invention now will be described with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, like numbers refer to like elements. It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. As used herein the term “and/or” includes any and all combinations of one or more of the associated listed items. Like numbers refer to like elements throughout.
The half-bridge circuits 110 and the connection terminals 120, 130 are supported by a frame 140. The frame 140 may include any of a number of different mechanical structures, including, but not limited to molded cases (with or without integral heat sinks) and composite structures including, for example, combinations of structural members and printed circuit board(s). Although the module 100 is shown as using IGBTs, it will be appreciated that the half-bridge circuits 110 may use other devices, such as field-effect transistors (FETs) or silicon controlled rectifiers (SCRs). The external connection terminals 120, 130 may include any of a number of different types of connection terminals, including, but not limited to, solderable terminals, compression-type terminals (e.g., socket, pin, blade), and screw terminals.
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In embodiments of the invention illustrated in
Some embodiments of the invention arise from a novel realization that a potentially more useful power conversion module for multi-phase applications may include more than the three half-bridges provided in conventional modules, such as IGBT “six packs.” For example, in many applications, it may be desired to provide neutral modulation in addition to phase modulation in an inverter, as shown, for example, in U.S. patent application Ser. No. 10/763,962 (Attorney Docket No. 9060-204), filed Jan. 23, 2004 and incorporated herein by reference in its entirety. In other applications, it may be desirable to provide battery conversion and/or DC bus balancing capability in combination with three-phase power conversion. Potential advantages of power conversion modules such as those shown in
The UPS 500 further includes a second module 520 that includes three half-bridge circuits 523 that are configured as an inverter that couples the DC busses 501, 502 to an AC bus 30. The second module 520 includes three inductors 524 that couple respective ones of the three half-bridge circuits 523 to respective phases Aout, Bout, Cout of the AC bus 30, and a fourth inductor 526 that couples a fourth half-bridge circuit 525 to a neutral Nout of the AC bus 30. The fourth half-bridge circuit 525 may be used as a neutral modulator as described, for example, in the aforementioned U.S. patent application Ser. No. 10/763,962. The second module 520 further includes a storage capacitor 528 coupled between the DC busses 501, 502. For purposes of clarity of illustration, control circuitry for driving the half-bridge circuits 513, 515, 523, 525 is not shown in
The UPS 600 further includes a second module 620 that includes three half-bridge circuits 623 that are configured as an inverter that couples the DC busses 601, 602 to an AC bus 30. The second module 620 includes three inductors 624 that couple respective ones of the three half-bridge circuits 623 to respective phases Aout, Bout, Cout of the AC bus 30, and a fourth inductor 626 that couples a fourth half-bridge circuit 625 to a neutral Nout of the AC bus 30. The fourth half-bridge circuit 625 may be used as a neutral modulator as described above. The second module 620 further includes a storage capacitor 628 coupled between the DC busses 601, 602. For purposes of clarity of illustration, control circuitry for driving the half-bridge circuits 613, 615, 623, 625 is not shown in
The module 700 illustrated in
In the drawings and specification, there have been disclosed exemplary embodiments of the invention. Although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined by the following claims.