H02H 7/045
Differential protection of transformers
H02H7/045 (Differential protection of transformers) appears on 88 US grants and 74 published applications in this corpus.
Search patents in H02H- Granted patents
- 88
- Published applications
- 74
- Assignees
- 63
- Inventors
- 219
- Latest grant
- 16 Sep 2025
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 1 | 0 |
| 1986 | 0 | 0 |
| 1987 | 2 | 0 |
| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 1 | 0 |
| 1992 | 2 | 0 |
| 1993 | 1 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 1 | 0 |
| 1998 | 4 | 0 |
| 1999 | 1 | 0 |
| 2000 | 0 | 0 |
| 2001 | 1 | 1 |
| 2002 | 4 | 0 |
| 2003 | 2 | 1 |
| 2004 | 2 | 5 |
| 2005 | 2 | 0 |
| 2006 | 0 | 1 |
| 2007 | 2 | 4 |
| 2008 | 3 | 2 |
| 2009 | 0 | 4 |
| 2010 | 2 | 3 |
| 2011 | 5 | 1 |
| 2012 | 0 | 1 |
| 2013 | 4 | 4 |
| 2014 | 0 | 3 |
| 2015 | 2 | 5 |
| 2016 | 4 | 1 |
| 2017 | 3 | 10 |
| 2018 | 5 | 2 |
| 2019 | 3 | 3 |
| 2020 | 5 | 3 |
| 2021 | 4 | 7 |
| 2022 | 5 | 3 |
| 2023 | 4 | 3 |
| 2024 | 6 | 3 |
| 2025 | 3 | 1 |
| 2026 | 0 | 3 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- High-impedance differential protection using a diversity of signals16 Sep 2025US 12,418,168 B2Schweitzer Engineering Laboratories, Inc.
- Restricted earth fault relay15 Apr 2025US 12,278,479 B2Mitsubishi Electric Corporation
- Differential protection using instrument transformer signal transducers4 Mar 2025US 12,244,135 B2Schweitzer Engineering Laboratories, Inc.
- System and method for restraining differential bias19 Nov 2024US 12,149,063 B2Schneider Electric (Australia) PTY LTD
- Transformer overcurrent protection1 Oct 2024US 12,107,410 B2S&C Electric Company
- Quotient differential protection for electric power delivery systems9 Jul 2026US 2026/0196823 A1Schweitzer Engineering Laboratories, Inc.
- A fault discrimination and a current transformer saturation detection for a differential protection system25 Jun 2026US 2026/0180308 A1Hitachi Energy Ltd
- High-speed high-sensitivity transformer differential protection using enhanced restraining techniques12 Mar 2026US 2026/0074509 A1Schweitzer Engineering Laboratories, Inc.
- Protective relay device31 Jul 2025US 2025/0246894 A1Mitsubishi Electric Corporation
- Restricted Earth Fault Relay5 Sep 2024US 2024/0297496 A1Mitsubishi Electric Corporation
Most cited
By later US patents
- Differential protection device of a power transformer110US 5,784,233 AEcole Superieure d'Electricite Supelec · 1998
- Method and device for testing differential protection relays or differential protection relay systems68US 6,396,279 B1Omicron Electronics GmbH · 2002
- System for power transformer differential protection58US 6,356,421 B1Schweitzer Engineering Labs., Inc. · 2002
- Digital current differential system49US 6,456,947 B1General Electric Company · 2002
- Digital current differential system43US 5,809,045 AGeneral Electric Company · 1998