Power inverter with improved heat sink configuration

Abstract

An inverter for producing AC power from a DC source is disclosed. The inverter uses a transformer and switches to convert current from a battery or other DC source into AC power that can be used to power household appliances or other devices. The primary windings of the transformer are directly connected to a heat sink to which the switches are mounted with electrical connection between the transformer and switches being via the heat sink. The connection point on the heat sink for the primary windings of the transformer is spatially removed from the locations of the switches to facilitate heat dissipation at both locations. The primary windings of the transformer are formed from a tape or ribbon-like conductor having a cross-sectional area that allows the construction of a relatively compact transformer while also providing primary conductors of relatively large cross section. Use of tape-like conductors in the primary windings significantly simplifies the interconnection of the end of the primary winding both to a bus bar and the heat sink. Since the tape-like conductor of the transformer can be bolted directly to the flat surface of a bus bar or heat sink without using an intermediate terminal or lug, and since a relatively large contact area is established, ohmic contact resistance is minimized thus reducing the generation of heat. In one embodiment, a wedge configuration is used to mount the switches of the primary windings to the heat sink. The mounting wedge includes two flexible plate-like sections that hold both the tab and the body of the switch against the adjoining side wall of the heat sink.