Solid-State Transformer Control Patents: Leaders & White Space 2026
- Filing activity peaked in 2019 at eight records and has not returned to that level since, with the 2022 midpoint sitting at just one filing — a flat-to-declining trend rather than a growing one.
- China's receiving office accounts for roughly half the corpus (13 of 27 records), with the United States a distant second at six, showing filing activity is geographically concentrated.
- The most-cited record draws 66 citations against a next tier in the teens and twenties, meaning influence in this dataset is dominated by a small handful of foundational modular H-bridge and DC power-flow filings.
What this landscape covers
Solid-state transformer (SST) control systems govern how modular power-electronic converters — typically cascaded H-bridge or dual-active-bridge stages — balance voltage and manage power flow across low- and high-voltage sides without a conventional line-frequency transformer core. This landscape isolates records at the intersection of modular converter control, voltage balancing control, closed-loop control and power flow control within the H02M power-conversion classification family, plus adjacent grid, EV and magnetics classes.
The dataset spans 27 patent families published between 2015 and the 2026 cut-off. Because publication trails filing by roughly 18 months, the most recent one to two years in the trend chart will read lower than actual filing activity once those applications clear examination and publish.
Filing trend and technology composition
The two views below separate when activity happened from where it sits technically — useful for telling a maturing niche apart from one still being defined.
A single peak year, not a growth curve
Filings rose to eight in 2019, the high point of the series, then fell back toward the 2022 midpoint of one record. There is no second wave visible yet in the published data, though the 18-month publication lag means 2025-2026 figures are still incomplete.
Power conversion dominates; grid integration is the largest adjacency
All 27 records classify under H02M (power conversion), confirming the search scope. H02J (power supply and grid systems) appears in nine records, making grid-side integration the clearest secondary theme; EV propulsion (B60L), commerce/data processing (G06Q) and magnetics (H01F) each appear once, marking thin but present adjacent branches rather than developed sub-fields.
Shares are the percentage of the 27 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Solid-State Transformer Control System with Eureka
This page is one run against one query. Ask Eureka your own question about solid-state transformer control system and every answer comes back with the patent numbers behind it.
Try EurekaMost-cited records and a representative claim
US10554144B2 — Dual voltage and current loop linearization and voltage balancing control for a solid state transformer
Filed by Nanyang Technological University, this patent covers a control method that divides a dual active bridge (DAB) power reference across the low-voltage DC link, splits the resulting current reference across N DAB modules, and — during normal power regulation — corrects capacitor voltage deviation at the high-voltage side of individual modules against the average HV DC bus voltage.Abstract condensed from the granted claim language; see the full record for exact scope.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | CN103956911A | 一种模块化H桥级联型多电平互平衡电力电子变压器 | 66 |
| 2 | WO2021017170A1 | 多端口直流潮流控制的模块化多电平变流器及控制方法 | 20 |
| 3 | CN110445400A | 多端口直流潮流控制的模块化多电平变流器及控制方法 | 19 |
| 4 | CN203827197U | 一种模块化H桥级联型多电平互平衡电力电子变压器 | 15 |
| 5 | CN104993713A | 一种双PWM固态变压器的控制方法 | 13 |
| 6 | US20250279730A1 | Solid-state transformer | 8 |
| 7 | CN111371117A | 面向港口供电的基于模块化多电平矩阵型电力电子变压器拓扑及其控制方法 | 8 |
| 8 | CN115173717A | 输入串联输出并联的固态变压器系统及辅助电源获取与输入电压均压的方法 | 6 |
| 9 | CN110492765A | 一种电容隔离型三相电力电子变压器 | 3 |
| 10 | US10554144B2 | Dual voltage and current loop linearization control and voltage balancing control for solid state transformer | 3 |
Citation counts reflect influence within this searched corpus and skew toward older filings; they are not a measure of current commercial relevance.
Patent titles are shown in the language they were filed in, not translated, so that each record stays verifiable against the original filing — a translated title will not match in Eureka or in any national register. Each row carries its publication number; clicking a row searches Eureka by that number.
Put your own technology through the same analysis
Eureka on the web
When you want the answer in the next five minutes.
The agent works the prompt against patents and technical literature, citing every source.
Run your analysis now →MCP server & REST API
When it has to run inside your own pipeline.
Patent search, landscape analysis and assignee resolution as MCP tools. Drop them into any agent framework, or call REST directly.
Browse MCP servers →What the numbers indicate
Three read-throughs from the trend, citation and geographic data that matter for a filing or freedom-to-operate decision.
Activity has cooled since 2019
The corpus peaked at eight filings in 2019 and dropped to one by the 2022 midpoint, with no sustained rebound visible in published data. That pattern is more consistent with a technology that had an early burst of foundational filings than one currently scaling.
Influence sits with a small set of modular H-bridge filings
The most-cited record draws 66 citations, more than triple the next tier (19-20). Two of the top five citation counts trace to the same modular H-bridge cascaded multilevel design, suggesting that architecture is the reference point competitors and examiners keep returning to.
Filing is concentrated, not global
China accounts for roughly half the corpus, the United States about a fifth, and the remainder splits thinly across India, Europe, Singapore and the PCT route. A filer targeting only the US or EPO would miss the majority of documented prior art in this field.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to solid-state transformer control system, with the prior art for and against each one.
Who holds the claim space
Universities and Chinese state-grid entities appear alongside a small set of industrial players; recent-year momentum is flat across the tracked assignees, consistent with the overall filing decline.
Joint filings cluster around one university-industry link
The strongest co-assignee relationship in the dataset pairs Shanghai Jiao Tong University with Delta Electronics' Shanghai management entity across three joint filings, with two further pairs involving State Grid Corporation and the China Electric Power Research Institute.
No assignee is currently accelerating
Every assignee tracked for recent-year momentum — including Shanghai Jiao Tong University, Nanyang Technological University, Delta Electronics and State Grid — shows zero filings in the latest year, and Delta Electronics' industrial arm shows a -100% year-on-year change.
Universities, state grid bodies and one Taiwanese manufacturer
The ranking mixes Chinese universities and research institutes, State Grid-affiliated entities, a Singaporean university, and Delta Electronics' Taiwan and Shanghai entities — a base broader than a single dominant corporate filer.
| Assignee | Recent year | YoY |
|---|---|---|
| Shanghai Jiao Tong University | 0 | — |
| Nanyang Technological University | 0 | — |
| Delta Electronics (Shanghai) Management Co., Ltd. | 0 | — |
| Institute of Electrical Engineering, Chinese Academy of Sciences | 0 | — |
| State Grid Corporation of China | 0 | — |
| Delta Electronics, Inc. | 0 | -100% |
| China Electric Power Research Institute Co., Ltd. | 0 | — |
| SR UNIVERSITY | 0 | -100% |
Where to take this analysis
The dataset points to specific follow-up work rather than a single conclusion — the flat trend and thin adjacencies both suggest different actions.
Check freedom-to-operate against the top-cited cluster
The 66-citation and 19-20 citation records share a modular H-bridge lineage; any new cascaded multilevel SST control filing should be checked against that specific family before drafting claims.
Run a claim comparison in EurekaWatch for the 2025-2026 publication catch-up
Because publication lags filing by about 18 months, the apparent decline after 2019 may partly reverse as recent applications clear the pipeline; re-running the trend query periodically will sharpen that picture.
Set up a monitoring search in EurekaExplore the thin adjacent branches before committing claim language
EV propulsion, grid business-process and magnetics overlaps each show only a single record — enough to signal interest, not enough to confirm the space is closed.
Explore white space in EurekaCommon questions about this landscape
The corpus is led by a mix of Chinese universities and research institutes, State Grid-affiliated entities, Nanyang Technological University, and Delta Electronics' Taiwan and Shanghai arms. No single assignee dominates the 27-family dataset outright; instead, filing is spread across academic and state-grid players with some industrial co-filing. Shanghai Jiao Tong University and Delta Electronics' Shanghai entity form the strongest joint-filing relationship in the data, having filed together three times.
Based on this dataset, no — filings peaked at eight in 2019 and had fallen to one by the 2022 midpoint, with no clear rebound visible in published records since. That said, publication lags filing by roughly 18 months, so 2025 and 2026 figures are likely undercounted and could revise upward. Treat the recent-year numbers as provisional rather than a confirmed continued decline.
China's receiving office accounts for 13 of the 27 records, roughly half the corpus, followed by the United States with six. India, the European Patent Office, Singapore and the PCT route each account for a small remainder. A search or freedom-to-operate review limited to US or European filings alone would miss the majority of the documented prior art in this field.
US10554144B2, assigned to Nanyang Technological University, claims a control method for solid-state transformers that divides a dual-active-bridge power reference across low-voltage DC link modules and corrects high-voltage-side capacitor voltage deviation against the average DC bus voltage during normal power regulation. It is a specific voltage-balancing and current-loop linearization method rather than a broad architectural claim, so it most directly constrains other DAB-module voltage-balancing schemes rather than SST control generally. Anyone designing a competing balancing method should compare their correction mechanism against this specific reference-current-division approach.
The classification data shows H02M (power conversion) fully saturated across all 27 records, but adjacent areas are thin: EV propulsion integration, grid-side power-flow coordination, fault-tolerant module bypass control, and magnetics-integrated balancing each appear in only one or a handful of records. These thin branches are candidates for new claim positions, though thin representation alone does not confirm the space is technically open — it may simply be underexplored or hard to differentiate from the dense H02M core.
Research Solid-State Transformer Control System in depth with Eureka
Go past this page: query the whole solid-state transformer control system corpus yourself, in your own scope.
Every answer comes back with patent numbers you can open.
Disclaimer. This page is generated from Patsnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing on this page constitutes an exhaustive prior-art, novelty, freedom-to-operate, or validity search, nor does it constitute legal, financial, investment, or professional advice, and it should not be relied upon as such. Any patent, commercial, or strategic decision should be verified independently and reviewed with qualified patent, legal, and domain professionals. Patsnap makes no warranties, express or implied, as to the accuracy, completeness, or fitness for any particular purpose of the information presented.
Machine translation. Assignee and organisation names originally recorded in Chinese, Japanese or Korean have been rendered into English by an AI translation step so that the tables stay readable. These renderings are best-effort and may not match a company’s registered English name; the original name is what the underlying patent record carries, and it is what any Eureka query launched from this page uses.