Power Quality Compensation Patent Landscape 2026
Power Quality Compensation Patent Landscape in 2026
State Grid Corporation of China commands the field with the largest portfolio among all ranked filers, while a tight cluster of Japanese, European, and American incumbents controls the next tier. The field has reached maturity — annual filings plateaued near their 2019 peak and have since eased, though the multi-year corpus remains substantial.
State Grid leads a concentrated field; Japanese and European incumbents hold the next tier
China sits atop Toshiba follows with 393 patent families, and Mitsubishi Electric, Fuji Electric, and Vestas Wind Systems round out the top five — together those five account for 27% of the hundred largest filers’ combined total.
The top-five share of 27% signals meaningful concentration at the apex, with a visible tier gap between State Grid / Toshiba and the cluster of players ranked third through tenth (Mitsubishi Electric at 207, Fuji Electric at 180, Vestas at 164, General Electric at 163, Alstom at 157, Siemens Energy at 156, China Electric Power Research Institute at 151, and ABB at 150).
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 1 | State Grid Corporation of China | 642 | |
| 2 | Toshiba Corporation | 393 | |
| 3 | Mitsubishi Electric Corporation | 207 | |
| 4 | Fuji Electric Co., Ltd. | 180 | |
| 5 | Vestas Wind Systems A/S | 164 | |
| 6 | General Electric Company | 163 | |
| 7 | Alstom Technology Ltd. | 157 | |
| 8 | SIEMENS ENERGY GLOBAL GMBH & CO KG | 156 | |
| 9 | China Electric Power Research Institute Co., Ltd. | 151 | |
| 10 | ABB (Switzerland) AG | 150 |
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 11 | GE Technology GmbH | 149 | |
| 12 | Siemens AG | 144 | |
| 13 | Hitachi Energy Ltd. | 132 | |
| 14 | Toshiba Mitsubishi-Electric Industrial Systems Corporation (TMEIC) | 128 | |
| 15 | Hitachi, Ltd. | 126 | |
| 16 | ABB Research Ltd. | 108 | |
| 17 | Nissin Electric Co., Ltd. | 96 | |
| 18 | LS Electric Co., Ltd. | 93 | |
| 19 | Electric Power Research Institute of China Southern Power Grid | 81 | |
| 20 | North China Electric Power University | 78 |
The leaders’ positions reflect decades of grid-integration and power-electronics investment. State Grid’s dominance is reinforced by its extensive co-filing network with provincial subsidiaries and research institutes, creating a structurally defensive cluster that is difficult to challenge on volume alone.
Filings from the most recent 18–24 months are subject to publication lag and will undercount actual activity; conclusions about very recent trends should be treated as provisional. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Peak activity was 2019; grid-systems dominates the technology mix
The filing trend and technology composition together reveal a field that built rapidly through the late 2010s, plateaued, and is now distributing innovation across an increasingly broad set of sub-technologies beyond its core grid-systems base.
Annual filing trend
Annual filings climbed from 554 in 2017 to a peak of 781 in 2019, then stepped down and stabilised in the 630–680 range through 2023. The 2024 and 2025 counts reflect publication lag and should not be read as a structural decline. The multi-year trajectory confirms a maturing, not collapsing, field.
↗ Hover for values · click a bar to ask EurekaTechnology composition
H02J (Power supply and grid systems) is the overwhelming primary branch, reflecting the grid-integration core of the field. H02M (Power conversion) is a clear secondary cluster. Further down, H02B (switchboards and substations), G05F (variable control), H02H (protective circuits), H02P (motor and generator control), and G01R (electrical measurement) represent established but comparatively lighter sub-areas. Emerging branches such as F03D (wind turbines), B60L (electric vehicles), and G06N (AI models) signal the field’s gradual convergence with adjacent energy and digital domains.
↗ Hover for values · click a bar to ask EurekaHighly cited patent families surfaced by the query
Citation-heavy patent families returned by the query. Use this section as citation context, not as a curated list of the most topic-specific patents.
Power quality compensation system, a power electro…
A power quality compensation system and a power quality compensation method are provided. The power quality compensation apparatus includes an input filter, a power electronic converter, a controller configured to control the power electronic converter, and a plurality of inductors connected to the power electronic converter. The power quality compensation… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Multilevel cascade voltage source inverter with se… | 555 |
| 2 | System, method and computer program product for en… | 403 |
| 3 | System, method, rotating machine and computer prog… | 333 |
| 4 | Power line conditioner using cascade multilevel in… | 315 |
| 5 | DC-DC and DC-AC power conversion system | 295 |
| 6 | System, method and computer program product for en… | 283 |
| 7 | System, method and computer program product for en… | 258 |
| 8 | Hybrid topology for multilevel power conversion | 256 |
Ranked by total forward citations. Citation counts favour older and broadly cited patent families, and broad or adjacent patents may appear when they match the search scope. Treat this section as citation context, not as a curated list of the most topic-specific patents. Some patent titles may be shown in their original, non-English language where an accurate translation could not be guaranteed.
What the competitive structure means for R&D investment decisions
China-heavy jurisdiction profile shapes where differentiation is still achievable and where barriers are highest.
Field is in maturity — annual volume has eased from its 2019 peak
Annual filings peaked at 781 in 2019 and have plateaued in the 630–680 range since, consistent with a mature technology field. Incremental improvement and system-level integration now drive activity more than foundational invention. New entrants face a large installed patent base; differentiation through niche sub-fields or cross-domain applications is more tractable than broad platform claims.
Lifecycle: MaturityTop five hold 27% of the hundred largest filers’ volume — concentrated but not monopolised
A 27% share among the top five of the hundred largest filers indicates meaningful but not extreme concentration. The tier-two cluster (ranks 3–10) is closely packed, suggesting competitive pressure among incumbents. The gap between State Grid (642) and Toshiba (393) is the sharpest in the ranking, giving State Grid a structural lead that is reinforced by its co-filing ecosystem rather than individual inventors alone.
Concentration: HighState Grid anchors a hub-and-spoke network; Mitsubishi Electric and Toshiba co-file closely
State Grid Corporation of China and China Electric Power Research Institute are the most active co-filers with 86 joint patent families. State Grid also co-files extensively with its provincial subsidiaries — Jiangsu (37), Liaoning (32), Hunan (31), and the State Grid Smart Grid Research Institute (30). Outside China, Mitsubishi Electric and Toshiba Mitsubishi-Electric Industrial Systems (TMEIC) collaborate on 26 joint families, reflecting deep integration between parent and joint-venture entities in the Japanese supply chain.
Collaboration: Hub-spokeChina dominates filings; US, Europe, and Japan are meaningful secondary markets
China accounts for the largest share of patent records by a wide margin, reflecting both State Grid’s volume and the country’s grid-modernisation investment cycle. The United States, Europe (EPO), and Japan represent the next tier of activity, followed by India, WIPO/PCT, Germany, and Canada. South Korea and Australia are active secondary markets. This jurisdiction spread signals that leading applicants pursue multi-market protection, making freedom-to-operate analysis across at least the US, EPO, and Japan essential for any commercialisation strategy.
Geography: China-ledGo beyond the landscape: Eureka’s TRIZ Solution agent breaks down an R&D problem and returns patented concept solutions, each with a technical approach and cited patent & literature evidence.
| Applicant | Collaborator | Co-filings |
|---|---|---|
| State Grid Corporation of China | China Electric Power Research Institute Co., Ltd. | 86 |
| State Grid Corporation of China | State Grid Jiangsu Electric Power Co., Ltd. | 37 |
| State Grid Corporation of China | State Grid Liaoning Electric Power Co., Ltd. | 32 |
| State Grid Corporation of China | State Grid Hunan Electric Power Co., Ltd. | 31 |
| State Grid Corporation of China | State Grid Smart Grid Research Institute Co., Ltd. | 30 |
| Mitsubishi Electric Corporation | Toshiba Mitsubishi-Electric Industrial Systems Corporation (TMEIC) | 26 |
| State Grid Corporation of China | North China Electric Power Research Institute Co., Ltd. | 23 |
| State Grid Corporation of China | XJ Group Corporation | 22 |
| State Grid Corporation of China | State Grid Tianjin Electric Power Company Marketing Service Center | 21 |
| State Grid Corporation of China | State Grid Beijing Electric Power Co. | 20 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
State Grid leads on grid-systems breadth; Toshiba and Mitsubishi Electric anchor power-electronics depth
The top two filers differ in portfolio emphasis: State Grid concentrates almost entirely on H02J grid-systems integration, while Toshiba balances grid systems with significant variable-control and power-conversion coverage. Both are large enough to set de facto claim standards in their respective sub-areas.
State Grid Corporation of China
State Grid leads all filers with 642 patent families, concentrated heavily in H02J grid-systems integration (593 sub-class records) and reinforced by H02J13 smart-grid control and G06Q50 utility data applications. Recent momentum is essentially flat at -3% versus the prior three-year period, reflecting a stable defensive posture rather than an acceleration phase. The hub-and-spoke co-filing network with provincial subsidiaries amplifies effective portfolio coverage well beyond the headline count.
families: 642Toshiba (KK Toshiba)
Toshiba holds 393 patent families — the second largest in the ranking — with a notably diversified focus spanning H02J grid systems (314 records), G05F variable control (262 records), and H02M power conversion (76 records). This breadth in voltage-regulation and conversion technology distinguishes Toshiba from most rivals and positions it across both utility and industrial compensation applications. Applicant momentum data for the Toshiba group entity (KK Toshiba) was not separately broken out in the momentum evidence; trajectory should be assessed alongside the TMEIC joint-venture entity, which shows a sharp recent decline of -84%.
families: 393| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| State Grid Corporation of China | 101 | ▬ -3% |
| Siemens AG | 3 | ▼ -85% |
| Mitsubishi Electric Corporation | 13 | ▼ -35% |
| Vestas Wind Systems A/S | 10 | ▲ new entrant |
| Toshiba Mitsubishi-Electric Industrial Systems Corporation (TMEIC) | 10 | ▼ -84% |
| China Electric Power Research Institute Co., Ltd. | 31 | ▬ -3% |
Under-served adjacent branches worth monitoring
Within the power quality compensation corpus, several IPC branches show meaningful patent-record counts but low share relative to the dominant H02J core, suggesting areas where the field’s core techniques are applied with comparatively less competitive density.
H02H · Protective circuit arrangements
H02H holds 408 patent records — roughly 2% of the branch distribution — despite being technically adjacent to compensation systems, where fault ride-through and surge protection are integral to grid-connected converters. The relatively sparse coverage compared to H02J and H02M suggests that protective-circuit integration with active compensation remains less contested. Researchers with expertise in solid-state protection or intelligent fault-isolation could find meaningful filing space here, particularly for next-generation inverter-based resource protection.
Search this in Eureka →H02P · Control of motors & generators
H02P (control of motors and generators) holds 370 patent records — approximately 2% share — even though motor-drive compensation and generator-side reactive power control are core use cases for static VAR compensators and active power filters in industrial settings. Vestas and General Electric show some H02P activity through their wind-turbine portfolios, but the branch is sparsely covered relative to its technical importance. Entry paths include variable-speed drive compensation for industrial loads and doubly-fed induction generator reactive support, both areas with growing demand from industrial decarbonisation initiatives.
Search this in Eureka →How leaders differ by technology route across grid systems, power conversion, and control
Strength of each leader across the main technology routes.
| Player | H02J 3 · Power supply & grid systems | H02M 7 · Power conversion (AC/DC etc.) | H02B 1 · Power switchboards & substations | G05F 1 · Electric/magnetic variable control | H02M 1 · Power conversion (AC/DC etc.) |
|---|---|---|---|---|---|
| Toshiba Corporation | Strong · 314 | Emerging · 47 | Absent | Strong · 262 | Emerging · 33 |
| State Grid Corporation of China | Strong · 593 | Absent | Emerging · 29 | Absent | Absent |
| Mitsubishi Electric Corporation | Strong · 151 | Strong · 88 | Absent | Strong · 84 | Emerging · 30 |
| Fuji Electric Co., Ltd. | Strong · 134 | Moderate · 37 | Absent | Strong · 96 | Moderate · 40 |
| Siemens AG | Strong · 189 | Moderate · 49 | Absent | Emerging · 20 | Emerging · 34 |
| General Electric Company | Strong · 215 | Absent | Absent | Absent | Absent |
| Alstom Technology Ltd. | Absent | Strong · 136 | Absent | Absent | Strong · 77 |
Frequently asked questions
The corpus contains 5,689 patent families in scope, spanning utility-scale grid compensation, industrial power electronics, and increasingly wind and EV-adjacent applications.
State Grid Corporation of China leads with 642 patent families, followed by Toshiba with 393 and Mitsubishi Electric with 207. The top five filers collectively account for 27% of the hundred largest filers’ combined total.
The field is in a maturity stage. Annual filings peaked at 781 in 2019 and have since plateaued in the 630–680 range. The most recent two years (2024–2025) show lower counts that reflect publication lag rather than a structural decline. The multi-year corpus remains substantial.
China is the dominant jurisdiction by patent-record volume, followed by the United States, Europe (EPO), Japan, India, and WIPO/PCT. Germany, Canada, and Australia are active secondary markets. Any freedom-to-operate analysis should cover at minimum China, the US, EPO, and Japan.
The most-cited work covers multilevel cascade voltage-source inverters (555 citations), energy enhancement systems and methods (403 and 283 citations), rotating machine control programs (333 citations), power line conditioners using cascade multilevel inverters (315 citations), DC-DC and DC-AC power conversion systems (295 citations), and hybrid multilevel power conversion topologies (256 citations). These foundational patents define the dominant technical approaches in the field.
State Grid Corporation of China anchors the most active collaboration network, with its densest co-filing relationship being with China Electric Power Research Institute (86 joint patent families). State Grid also co-files heavily with its Jiangsu, Liaoning, Hunan, and Beijing provincial subsidiaries and with the State Grid Smart Grid Research Institute. In Japan, Mitsubishi Electric and TMEIC (Toshiba Mitsubishi-Electric Industrial Systems) collaborate on 26 joint families.
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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.