In this landscape, a wide-bandgap device means a silicon carbide (SiC) MOSFET or gallium nitride (GaN) switch claimed as part of the converter's switching stage, rather than merely mentioned as an implementation option. The search specifically requires these device terms to appear in the claims or description alongside converter-architecture language, which filters out generic power-electronics filings that happen to reference SiC or GaN in passing. This distinction matters because a patent that only lists wide-bandgap devices as an alternative to silicon is much weaker prior art than one that claims specific switching behaviour enabled by the device's properties.

The dataset shows filings building from a single record in 2017 to a peak of 15 in 2022, then falling off. This pattern typically means the core architectural claims — converter topology, basic switching schemes, resonant-circuit design — were staked out early, and later filers are left patenting narrower variations or specific applications. It does not necessarily mean interest in the technology is declining; it more often means the field's headline claim space is already occupied. Bear in mind that publication lag of roughly 18 months means the last one to two years in any such trend will always look thinner than they eventually turn out to be.

No single assignee shows a clear, sustained lead in this dataset. Organisations including Siemens, Fraunhofer, a Colorado university and several startup and individual-inventor filers all appear in the assignee set, but every one of them recorded zero filings in the latest tracked year. This is a fragmented ownership picture rather than a concentrated one, and the most-cited individual patents belong to older LLC-converter filings rather than to any currently active leader.

Start with the highest-cited records in the corpus, since citation count within a searched patent corpus is a reasonable proxy for how often examiners and applicants have already treated a filing as foundational. The two leading records here both describe an LLC circuit operated in the voltage-gain-above-unity region, and the Fraunhofer filing on commutation resonant-circuit switching timing is also heavily referenced. Because citation counts favour older filings, also run a fresh claim search on recent years rather than relying on the citation ranking alone.

The classification data shows every record concentrated in core power-conversion IPC class H02M, with only partial spillover into grid-interface (H02J) and EV-propulsion (B60L) classes. That leaves system-level integration — such as vehicle-to-grid control logic, GaN switch integration specifically within grid-tied power supplies, and multi-port bidirectional topologies — comparatively under-claimed relative to the converter topology itself. These branches show some filing activity but no concentrated ownership in this dataset, which is generally a better signal for a first-mover filing than a completely empty branch would be.