Converter topologies and control

An inverter for converting an input direct current (DC) waveform from a DC source to an output alternating current (AC) waveform for delivery to an AC grid, the inverter comprising:

• a controller having a processor and a memory;
• a transformer that includes a first winding, a second winding, and a third winding;
• a DC-AC inverter electrically coupled to the first winding of the transformer, wherein the DC-AC inverter is adapted to convert the input DC waveform to an AC waveform delivered to the transformer at the first winding;
• a cycloconverter electrically coupled to the second winding of the transformer, wherein the cycloconverter is adapted to convert an AC waveform received at the second winding of the transformer to the output AC waveform having a grid frequency of the AC grid, and wherein the second winding has at least one terminal, the cycloconverter having an inductor connected directly to the at least one terminal;
• and
• an active filter electrically coupled to the third winding of the transformer and comprising a plurality of electrical switches and one or more energy storage devices,
• wherein the controller is adapted to control the switching cycles of the plurality of electrical switches of the active filter to sink and source power with the one or more energy storage devices based on a mismatch in power between the DC source and the AC grid.

An inverter for converting an input direct current (DC) waveform from a DC source to an output alternating current (AC) waveform for delivery to an AC grid, the inverter comprising:

• a transformer that includes a first winding, a second winding, and a third winding;
• a DC-AC inverter electrically coupled to the first winding of the transformer, wherein the DC-AC inverter is adapted to convert the input DC waveform to an AC waveform delivered to the transformer at the first winding;
• a cycloconverter electrically coupled to the second winding of the transformer, wherein the cycloconverter is adapted to convert an AC waveform received at the second winding of the transformer to the output AC waveform having a grid frequency of the AC grid, and wherein the second winding has at least one terminal, the cycloconverter having an inductor connected directly to the at least one terminal;
• an active filter electrically coupled to the third winding of the transformer and comprising a plurality of electrical switches and one or more energy storage devices;
• a processor;
• and
• a memory comprising a plurality of instructions stored thereon that, in response to execution by the processor, causes the inverter to control the switching cycles of the plurality of electrical switches of the active filter to sink and source power with the one or more energy storage devices based on a mismatch in power between the DC source and the AC grid.