G01R 31/62
Testing of transformers
G01R31/62 (Testing of transformers) appears on 439 US grants and 523 published applications in this corpus.
Search patents in G01R- Granted patents
- 439
- Published applications
- 523
- Assignees
- 303
- Inventors
- 1,373
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 0 | 0 |
| 1978 | 2 | 0 |
| 1979 | 0 | 0 |
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 1 | 0 |
| 1984 | 2 | 0 |
| 1985 | 2 | 0 |
| 1986 | 0 | 0 |
| 1987 | 2 | 0 |
| 1988 | 3 | 0 |
| 1989 | 3 | 0 |
| 1990 | 1 | 0 |
| 1991 | 2 | 0 |
| 1992 | 1 | 0 |
| 1993 | 2 | 0 |
| 1994 | 2 | 0 |
| 1995 | 3 | 0 |
| 1996 | 3 | 0 |
| 1997 | 0 | 0 |
| 1998 | 1 | 0 |
| 1999 | 1 | 0 |
| 2000 | 3 | 0 |
| 2001 | 2 | 1 |
| 2002 | 5 | 5 |
| 2003 | 4 | 2 |
| 2004 | 4 | 5 |
| 2005 | 3 | 4 |
| 2006 | 7 | 1 |
| 2007 | 2 | 6 |
| 2008 | 1 | 3 |
| 2009 | 0 | 2 |
| 2010 | 4 | 7 |
| 2011 | 2 | 17 |
| 2012 | 1 | 9 |
| 2013 | 12 | 16 |
| 2014 | 9 | 20 |
| 2015 | 10 | 27 |
| 2016 | 16 | 29 |
| 2017 | 29 | 42 |
| 2018 | 25 | 33 |
| 2019 | 41 | 29 |
| 2020 | 34 | 40 |
| 2021 | 34 | 53 |
| 2022 | 29 | 34 |
| 2023 | 36 | 44 |
| 2024 | 41 | 32 |
| 2025 | 27 | 33 |
| 2026 | 23 | 29 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Monitoring a transformer comprising a tap changer6 Oct 2026US 12,754,255 B2Hitachi Energy Ltd
- Method and device for testing a voltage converter29 Sep 2026US 12,748,163 B2Omicron Electronics GmbH
- Current transformer polarity verification15 Sep 2026US 12,738,416 B2Google Inc.
- Method for simulating a transformer8 Sep 2026US 12,730,159 B2Siemens Energy Global GmbH & Co. KG
- Insulation detection method and apparatus for conversion system25 Aug 2026US 12,716,931 B2Delta Electronics (Shanghai) Co., Ltd.
- Abnormal vibration diagnosis system and method for transformer24 Sep 2026US 2026/0287682 A1Fortune Electric Co., Ltd.
- Current transformer polarity verification24 Sep 2026US 2026/0290685 A1Google Inc.
- Distribution transformer system and methods thereof17 Sep 2026US 2026/0279659 A1Ubicquia, Inc.
- Method for measuring transformer leakage magnetic field signals based on improved svmd combined with wavelet threshold method10 Sep 2026US 2026/0266926 A1Sanmen Nuclear Power Co., Ltd.
- Test device and method for testing a high-voltage or medium-voltage cable and method for testing a transformer arranged in a test device27 Aug 2026US 2026/0251728 A1B2 Electronics GmbH
Most cited
By later US patents
- Partial discharge monitoring system for transformers45US 6,774,639 B1TransGrid · 2004
- Advance manufacturing monitoring and diagnostic tool33US 8,643,539 B2Nokomis, Inc. · 2014
- Method and device for fault detection in transformers or power lines32US 7,812,615 B2ABB AB · 2010
- Portable tester and related method for determining the primary winding to secondary winding current ratio of an in-service current transformer28US 4,758,774 ASpecial Instruments Laboratory, Inc. · 1988
- Transformer fault analyzer27US 5,396,172 AOntario Hydro · 1995