Solid-State Transformer Patents

Solid-state transformer (SST) patents cover power-electronic-transformer-topology innovations; SiC medium-voltage-device innovations; dual-active-bridge/DC-DC innovations; and EV/grid-interface and control/protection innovations — with IP held by power-equipment majors, EV-charging/grid startups, and academic power-electronics groups (in a field replacing the conventional transformer with a smart power-electronic system). WHY SOLID-STATE TRANSFORMERS: the conventional transformer (iron core + copper windings at 60Hz) is bulky, heavy, passive, and 'dumb' — it only steps voltage up/down; a SOLID-STATE TRANSFORMER replaces it with a compact POWER-ELECTRONIC system (high-frequency switching + a small isolation transformer + SiC semiconductors) that not only changes voltage but adds SMART functions a normal transformer can't: BIDIRECTIONAL power flow, direct DC ports (no separate rectifier), voltage/reactive-power control, fault isolation, and grid services — making it valuable for EV FAST CHARGING (connecting medium-voltage grid directly to DC chargers), renewable/grid integration, DC microgrids, and data centers. MAJOR HOLDERS: ABB/HITACHI ENERGY, EATON, and EV-charging/grid startups, plus academic IP (FREEDM Systems Center/NC State pioneered SST research). Power-electronic-transformer topologies, SiC medium-voltage devices, dual-active-bridge/DC-DC, EV/grid interfaces, and control/protection are the core SST patent domains — and topology, SiC integration, EV charging, and control are the open whitespace.

Power-electronic-transformer-topology innovations; SiC medium-voltage-device innovations; dual-active-bridge/DC-DC innovations; and high-frequency-transformer/magnetics innovations represent core SST patent domains — and the converter architecture, the medium-voltage semiconductors, and the isolation stage are the foundational, high-value capabilities. POWER-ELECTRONIC-TRANSFORMER-TOPOLOGY PATENTS: the overall ARCHITECTURE — typically multi-stage (AC→DC at medium voltage, then a high-frequency isolated DC-DC, then DC→AC/DC output), often using MODULAR MULTILEVEL converters (many series cells to handle medium voltage with lower-voltage devices); SST topology (stage arrangement, modularity, cell design) is core, high-value IP (the architecture defines efficiency/cost/capability). SiC MEDIUM-VOLTAGE-DEVICE PATENTS: SSTs need switches that handle MEDIUM VOLTAGE (kV-class) efficiently at high frequency — high-voltage SILICON CARBIDE (SiC) MOSFETs (and their gate drives/packaging) are the enabler (silicon can't switch fast enough at these voltages); SiC MV device application/integration is high-value IP (SiC is what makes SSTs practical). DUAL-ACTIVE-BRIDGE / DC-DC PATENTS: the HEART of the SST — an isolated, bidirectional high-frequency DC-DC converter (dual-active-bridge or resonant) that transfers power across the isolation transformer and controls power flow; DAB/DC-DC topology and control (soft-switching, power-flow control) is core, high-value IP. HIGH-FREQUENCY-TRANSFORMER / MAGNETICS PATENTS: the small high-FREQUENCY isolation TRANSFORMER (vastly smaller than a 60Hz transformer) — core materials, winding, and especially medium-voltage INSULATION/thermal design; HF-transformer/magnetics methods are high-value (insulation at medium voltage + high frequency is hard). SST topology, SiC MV devices, dual-active-bridge, and HF magnetics are the highest-value core IP because the architecture, the medium-voltage switches, the isolation stage, and the compact transformer are exactly what make an SST work.

EV-fast-charging/grid-interface innovations; control innovations; protection/fault innovations; and efficiency/reliability/cost innovations represent additional SST patent domains — and the killer applications, the complex control, and surviving faults are where SSTs deliver value and face their hardest challenges. EV-FAST-CHARGING / GRID-INTERFACE PATENTS: the leading application — connecting the MEDIUM-VOLTAGE grid DIRECTLY to high-power DC fast chargers (skipping the bulky line-frequency transformer + separate rectifier), enabling compact, efficient, grid-friendly charging hubs; also DC microgrids, renewable/storage integration, and grid services (reactive power, voltage support); EV-charging and grid-interface SST applications/methods are high-value IP (the biggest commercial driver). CONTROL PATENTS: SSTs are COMPLEX multi-stage systems needing sophisticated CONTROL — coordinating stages, power-flow control, balancing modular cells, synchronization, and grid-forming/following behavior; control methods are high-value IP (control complexity is a real challenge — mind §101 for algorithmic claims, anchor in the power hardware). PROTECTION / FAULT PATENTS: protecting MEDIUM-VOLTAGE power electronics is HARD — semiconductors fail fast under fault, and there's no robust iron core to ride through; fault detection, protection schemes, and ride-through methods are CRITICAL, high-value IP (protection/reliability is a key barrier and differentiator). EFFICIENCY / RELIABILITY / COST PATENTS: achieving high efficiency, thermal management, reliability, and (the big one) COST competitive with a cheap, proven conventional transformer; efficiency/reliability/cost methods are valuable (cost vs the dumb-but-cheap incumbent transformer is the central economic hurdle). EV charging/grid interface, control, protection/fault, and efficiency/cost are the highest-value application IP because the killer use cases, taming control complexity, surviving faults, and beating the cheap incumbent on value are exactly what determine SST adoption.

Solid-state transformer startup IP strategy must navigate ABB/Hitachi Energy/Eaton and academic (FREEDM/NC State) portfolios, decades of power-electronics/converter prior art (dual-active-bridge, multilevel converters, and HF transformers are well-studied — the medium-voltage SST integration and applications are the novelty), the SiC dependence (SSTs ride on high-voltage SiC progress — and SiC device IP sits beneath), the topology-vs-device-vs-application split, the protection/reliability problem (medium-voltage power electronics are hard to protect — a key barrier and IP area), the cost imperative (must justify replacing a cheap, ultra-reliable conventional transformer — the central economic challenge), the EV-fast-charging killer app (the clearest near-term commercial driver), the heavy capital and grid-qualification/standards, and a landscape where topology, SiC integration, DAB/control, protection, and EV/grid applications are the durable assets; understand that core converters are well-trodden, so the durable IP is in medium-voltage SST topologies, SiC integration, DAB/control, protection/fault handling, HF magnetics, and EV-charging/grid applications — with system integration and reliability/protection know-how often the real moat, and that efficiency/cost, reliability/protection, application fit, and grid qualification matter as much as patents; identify whitespace in EV charging, protection, and topology. SST STARTUP IP STRATEGY: CORE CONVERTERS ARE OLD — MEDIUM-VOLTAGE SST TOPOLOGIES, SiC INTEGRATION, DAB/CONTROL, PROTECTION, HF MAGNETICS, AND EV/GRID APPLICATIONS ARE THE IP: patent MV SST topologies, SiC integration, dual-active-bridge/control, protection/fault, HF transformer design, and EV-charging/grid-interface applications; EV FAST CHARGING IS THE CLEAREST NEAR-TERM KILLER APP AND WHITESPACE: medium-voltage-direct DC fast charging (skipping the line-frequency transformer + rectifier) is the biggest commercial driver — application IP and design wins are high-value; PROTECTION/FAULT HANDLING IS A KEY BARRIER AND DEFENSIBLE IP: medium-voltage power electronics fail fast and lack iron-core ride-through — robust protection/fault methods are critical, high-value IP; SiC RIDES UNDERNEATH — INTEGRATION IS THE STARTUP VALUE: SSTs depend on high-voltage SiC (incumbent device IP) — your value is in integrating/applying it (topology, gate drive, packaging, control), not reinventing SiC; TOPOLOGY/MODULARITY IS CORE IP: the multi-stage/modular-multilevel architecture defines efficiency/cost/scalability — topology IP is foundational; CONTROL COMPLEXITY IS REAL IP (MIND §101): coordinating stages, cell balancing, and grid-forming control — claim concretely in the power hardware; HF MAGNETICS/INSULATION IS A HARD, VALUABLE NICHE: medium-voltage high-frequency transformer insulation/thermal design is difficult — defensible IP; COST VS THE CHEAP INCUMBENT IS THE CENTRAL HURDLE: a conventional transformer is cheap and ultra-reliable — SSTs must justify cost via the smart functions/DC ports/compactness they enable; EFFICIENCY/RELIABILITY/COST/QUALIFICATION MATTER AS MUCH AS PATENTS: efficiency, reliability/protection, application fit, and grid/standards qualification drive adoption; WHEN TO PATENT: NOVEL TOPOLOGY/SiC-INTEGRATION/CONTROL/PROTECTION/APPLICATION WITH MEASURED PERFORMANCE: file once a design shows measured results (efficiency + power density/size + protection/fault performance + control performance + cost + reliability) — measured efficiency, power density, protection/reliability, and cost are the critical SST IP metrics; KEY FTO CHECKLIST: ABB/Hitachi Energy/Eaton + FREEDM/NC State; power-electronics/converter prior art (DAB/multilevel/HF transformer); SST topology (multi-stage/modular-multilevel/cell); SiC medium-voltage devices/gate-drive/packaging (incumbent device IP); dual-active-bridge/resonant DC-DC (soft-switching/power-flow control); HF transformer/magnetics/medium-voltage insulation/thermal; EV fast charging/grid interface/DC microgrid/grid services; control (stage coordination/cell balancing/grid-forming, §101); protection/fault/ride-through; efficiency/reliability/cost; grid qualification/standards.