Abstract: Described herein are DC-DC converters with a ratio of the power output to volume of at least 2 kW per liter or even at least 4 kW per liter. Such DC-DC converters can operate at power levels of at least 150 kW or even at least 200 kW. A DC-DC converter comprises an enclosure and a front plate sealed against the enclosure using a set of fasteners. The DC-DC converter also comprises a converter unit comprising a switching sub-module, a diode sub-module, and an inductor as well as an additional converter unit comprising an additional switching sub-module, an additional diode sub-module, and an additional inductor. The switching sub-module and the additional switching sub-module or, more generally, the converter unit and the additional converter unit are configured to operate out of phase. The inductors are immersed cooled, the switching sub-modules are conductively cooled, while the diode sub-modules are convectively cooled.

Abstract: Described herein are DC-DC converters with a ratio of the power output to volume of at least 2 kW per liter or even at least 4 KW per liter. Such DC-DC converters can operate at power levels of at least 150 kW or even at least 200 kW. A DC-DC converter comprises an enclosure and a front plate sealed against the enclosure using a set of fasteners. The DC-DC converter also comprises a converter unit comprising a switching sub-module, a diode sub-module, and an inductor as well as an additional converter unit comprising an additional switching sub-module, an additional diode sub-module, and an additional inductor. The switching sub-module and the additional switching sub-module or, more generally, the converter unit and the additional converter unit are configured to operate out of phase. The inductors are immersed cooled, the switching sub-modules are conductively cooled, while the diode sub-modules are convectively cooled.

Abstract: Described herein are DC-DC converters with a ratio of the power output to volume of at least 2 kW per liter or even at least 4 kW per liter. Such DC-DC converters can operate at power levels of at least 150 kW or even at least 200 kW. A DC-DC converter comprises an enclosure and a front plate sealed against the enclosure using a set of fasteners. The DC-DC converter also comprises a converter unit comprising a switching sub-module, a diode sub-module, and an inductor as well as an additional converter unit comprising an additional switching sub-module, an additional diode sub-module, and an additional inductor. The switching sub-module and the additional switching sub-module or, more generally, the converter unit and the additional converter unit are configured to operate out of phase. The inductors are immersed cooled, the switching sub-modules are conductively cooled, while the diode sub-modules are convectively cooled.

Abstract: Described herein are DC-DC converters with electronic module cooling units used for air-convection cooling of some components of power electronic modules and conductive cooling of other components, e.g., switching sub-modules. A cooling unit may have a heat exchanger and a cooling plate, thermally coupled to one or more heat exchangers and one or more switching sub-modules. For example, the cooling plate can be positioned between and thermally coupled to heat exchangers. One fan can direct air through one heat exchanger and to one power electronic module as a part of convection cooling. An additional fan can direct air through the second heat exchanger and to the second power electronic module. The cooling plate can be also positioned between and thermally coupled to switching sub-modules of these power electronic modules thereby enabling conductive cooling. The plate-cooling liquid is pumped through the cooling plate.

Abstract: Described herein are vehicle charging systems, each comprising a recharge vehicle and a work vehicle configured to form an electrical connection and charge the work vehicle battery from the recharge vehicle battery. In some examples, this charging is performed at 500 kW or more or even at 1,000 kW or more. Furthermore, the connection and/or charging can be performed while both vehicles are moving (e.g., the recharge vehicle moving in front of the work vehicle). The recharge vehicle comprises one or more DC-DC converters, configured to boost a first voltage (V1) of the recharge vehicle battery to a second voltage (V2) of the work vehicle battery. It should be noted that these voltages vary depending on the state of charge of these batteries. In some examples, each DC-DC converter utilizes a combination of immersion, conductive, and convective cooling for different components of the converter.

Abstract: Described herein are DC-DC converters having various immersion-cooling features enabling high-power applications, such as cross-charging electric vehicles. For example, the inductor of a DC-DC converter may be formed using metal and insulator sheets stacked and wound into an inductor coil assembly. The metal sheet comprises grooves, extending parallel to the coil axis and forming coil fluid pathways through this assembly thereby providing immersion cooling to the inductor. An inductor-cooling liquid may be pumped through these fluid pathways while being in direct contact with the metal sheet, at least around the grooves. In some examples, these grooves are distributed along the entire length of the metal sheet. Multiple inductors may be used to enable operations of multiple converter units, e.g., operating out of phase. These inductors may be fluidically interconnectors and have the same cooling features.