H02H 3/28
Involving comparison of the voltage or current values at two spaced portions
Official title: involving comparison of the voltage or current values at two spaced portions of a single system, e.g. at opposite ends of one line, at input and output of apparatus {(for transformers H02H7/045)}
H02H3/28 (Involving comparison of the voltage or current values at two spaced portions) appears on 288 US grants and 257 published applications in this corpus.
Search patents in H02H- Granted patents
- 288
- Published applications
- 257
- Assignees
- 153
- Inventors
- 622
- Latest grant
- 25 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 8 | 0 |
| 1977 | 5 | 0 |
| 1978 | 8 | 0 |
| 1979 | 1 | 0 |
| 1980 | 4 | 0 |
| 1981 | 1 | 0 |
| 1982 | 1 | 0 |
| 1983 | 2 | 0 |
| 1984 | 0 | 0 |
| 1985 | 4 | 0 |
| 1986 | 3 | 0 |
| 1987 | 3 | 0 |
| 1988 | 1 | 0 |
| 1989 | 2 | 0 |
| 1990 | 1 | 0 |
| 1991 | 2 | 0 |
| 1992 | 2 | 0 |
| 1993 | 0 | 0 |
| 1994 | 1 | 0 |
| 1995 | 1 | 0 |
| 1996 | 2 | 0 |
| 1997 | 3 | 0 |
| 1998 | 3 | 0 |
| 1999 | 2 | 0 |
| 2000 | 1 | 0 |
| 2001 | 1 | 2 |
| 2002 | 6 | 4 |
| 2003 | 9 | 7 |
| 2004 | 8 | 9 |
| 2005 | 3 | 2 |
| 2006 | 3 | 2 |
| 2007 | 6 | 5 |
| 2008 | 2 | 8 |
| 2009 | 4 | 9 |
| 2010 | 5 | 9 |
| 2011 | 8 | 11 |
| 2012 | 11 | 12 |
| 2013 | 9 | 17 |
| 2014 | 12 | 13 |
| 2015 | 16 | 13 |
| 2016 | 12 | 8 |
| 2017 | 12 | 13 |
| 2018 | 7 | 16 |
| 2019 | 11 | 10 |
| 2020 | 15 | 13 |
| 2021 | 17 | 12 |
| 2022 | 13 | 9 |
| 2023 | 5 | 16 |
| 2024 | 14 | 16 |
| 2025 | 10 | 11 |
| 2026 | 8 | 10 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Current transformer sensing with saturation protection25 Aug 2026US 12,719,260 B2Hamilton Sundstrand Corporation
- Aircraft solid state power controller and method of operating an aircraft solid state power controller12 May 2026US 12,627,134 B2Hs Elektronik Systeme GmbH
- Protective device with multi-channel line current differential protection14 Apr 2026US 12,603,490 B2Schweitzer Engineering Laboratories, Inc.
- Multi-ended impedance-based fault locating for untransposed transmission lines17 Mar 2026US 12,578,374 B2Schweitzer Engineering Laboratories, Inc.
- Method for detecting a series resistance fault in a digital-electricity transmission system3 Mar 2026US 12,566,220 B2VoltServer, Inc.
- Fault response control in power converters3 Sep 2026US 2026/0261113 A1
- System for power line differential protection27 Aug 2026US 2026/0254241 A1Hitachi Energy Ltd
- Protective circuit for electric loads25 Jun 2026US 2026/0175694 A1Daimler Truck AG
- A fault discrimination and a current transformer saturation detection for a differential protection system25 Jun 2026US 2026/0180308 A1Hitachi Energy Ltd
- Systems and methods for channel asymmetry estimation and evaluation28 May 2026US 2026/0149303 A1Schweitzer Engineering Laboratories, Inc.
Most cited
By later US patents
- Power distribution system with fault protection using energy packet confirmation92US 8,068,937 B22011
- Zone arc fault detection80US 5,986,860 ASquare D Company · 1999
- Electrical line-fault detector and circuit breaker device72US 5,424,894 A1995
- Restraint-type differential relay72US 6,341,055 B12002
- Line differential protection system for a power transmission line66US 6,518,767 B1Schweitzer Engineering Laboratories, Inc. · 2003