Patent Application
20210135595
The subject matter disclosed herein generally relates to drives for loads and, more particularly, to a drive incorporating multilevel inverter modules.
A drive is an electronic device used to provide the proper electrical power to a load, such as a motor. In an HVAC environment, existing drives use 2-level inverter topology. When used in high-speed applications, this topology requires a large output filter to improve the output current quality. To reduce or eliminate the output filter, without increasing switching frequency, multilevel topologies can be used.
According to an embodiment, a drive is configured to provide power to a load. The drive includes a control unit including a controller and a driver located on a first substrate; a power unit including at least one inverter module located on a second substrate; an interconnect coupling the control unit and the power unit.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the second substrate comprises a thermal management feature.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the second substrate comprises a metal core printed circuit board.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the at least one inverter module is configured to convert DC power from a DC source to a multilevel AC waveform.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the at least one inverter module comprises three inverter modules arranged in parallel with the DC source, the drive configured to output a 2-level, three phase AC waveform.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the at least one inverter module comprises three inverter modules arranged in parallel with the DC source, the drive configured to output a 3-level, three phase AC waveform.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the at least one inverter comprises six inverter modules, a first three of the inverter modules arranged in parallel with the DC source, each of a second three of the inverter modules being in series with a respective one of the first three of the inverter modules, the drive configured to output a 5-level, three phase AC waveform.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the first three of the inverter modules are connected to the second three of the inverter modules by connections on the first substrate.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the at least one inverter module is a modular device.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the control unit further comprise a sensor configured to sense an electrical parameter of the power unit.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the electrical parameter includes AC current.
In addition to one or more of the features described herein, or as an alternative, further embodiments may include wherein the electrical parameter includes DC voltage.
Technical effects of embodiments of the present disclosure include the provision of a drive utilizing modular inverter modules to adapt to various load demands.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, that the following description and drawings are intended to be illustrative and explanatory in nature and non-limiting.
The present disclosure is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements.
The drivers 104 may be implemented using power amplifiers that receive control signals from the controller 102 and provide drive signals to inverter modules 202 in the power unit 200. Sensors 106 may sense one or more electrical parameters of the power unit 200, such as AC current or DC voltage. The controller 102 receives the sensed electrical parameters from the sensors 106 to alter the control signals provided to the drivers 104. The power unit 200 includes one or more inverter modules 202, which are described in detail herein with reference to
The control unit 100 and the power unit 200 may be formed on separate substrates. A first substrate 108 supports the controller 102, drivers 104 and sensors 106, and may be a printed circuit board (e.g., FR4). A second substrate 208 supports the inverter modules 202, and may be equipped with thermal management features. In one embodiment, the second substrate 208 is a metal core printed circuit board to improve dissipation of heat generated by the inverter modules 202. Other thermal management features may be employed on the second substrate 208 including heat sinks, fans, heat pipes, etc. The control unit 100 and the power unit 200 communicate over an interconnect 300, such as a ribbon cable, bus, etc.
Switches S1-S4 are controlled by drive signals from the drivers 104 to produce a multilevel AC waveform output by the inverter module 202 and supplied to load 16. A positive AC output terminal 210 provides the positive voltage of the AC waveform. A negative AC output terminal 212 provides the negative voltage of the AC waveform. A neutral AC output terminal 214 provides the neutral voltage of the AC waveform, if used.
In one embodiment, switches S1-S4 are wideband devices (GaN MOSFETs), although IGBTs, IGCT's, or other similar types of high-voltage switches may be utilized without departing from the scope of the disclosure. Switches S1-S4 are each associated with a diode. Each diode is connected with its cathode coupled to the drain and its anode coupled to the source of a switch, to serve as a freewheeling or flyback diode.
In operation, the controller 102 provides control signals to the drivers 104. The drivers 104 provide drive signals to the gate terminals of the switches S1-S4 in order to produce a multilevel AC waveform at the output terminals 210 and 212, and optionally 214. When a 2-level AC waveform is desired, switches S2 and S3 are not controlled and are in a non-conductive state. When a 3-level AC waveform is desired, all of switches S1-S4 are controlled by the drive signals.
Each inverter module 202 may be implemented with a single IC package (e.g., through hole mounted, surface mounted), so that adding and removing inverter modules 202 from a drive 14 is simplified. Embodiments of the drive 14 are compact, modular and expandable depending on application needs. The combination of modular inverter modules 202 and substrate 208 allows a high-density, automated assembly process and improved heat conduction to heatsinks. The same substrate 208 design and construction can be reconfigured to produce 2-level, 3-level, 5-level or N-level AC waveforms depending on the drive requirements. This enables low-cost and highly flexible designs.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof.
Those of skill in the art will appreciate that various example embodiments are shown and described herein, each having certain features in the particular embodiments, but the present disclosure is not thus limited. Rather, the present disclosure can be modified to incorporate any number of variations, alterations, substitutions, combinations, sub-combinations, or equivalent arrangements not heretofore described, but which are commensurate with the scope of the present disclosure. Additionally, while various embodiments of the present disclosure have been described, it is to be understood that aspects of the present disclosure may include only some of the described embodiments. Accordingly, the present disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
| Number | Date | Country | |
|---|---|---|---|
| 62930670 | Nov 2019 | US |
