H01F 38/38
For polyphase ac
Official title: for polyphase AC
H01F38/38 (For polyphase ac) appears on 37 US grants and 32 published applications in this corpus.
Search patents in H01F- Granted patents
- 37
- Published applications
- 32
- Assignees
- 33
- Inventors
- 89
- Latest grant
- 30 Apr 2024
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 1 | 0 |
| 1978 | 2 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 2 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 2 | 0 |
| 1993 | 1 | 0 |
| 1994 | 1 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 1 | 0 |
| 2001 | 1 | 0 |
| 2002 | 1 | 1 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 1 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 1 | 1 |
| 2010 | 1 | 1 |
| 2011 | 0 | 2 |
| 2012 | 1 | 0 |
| 2013 | 1 | 2 |
| 2014 | 0 | 1 |
| 2015 | 0 | 2 |
| 2016 | 1 | 5 |
| 2017 | 5 | 2 |
| 2018 | 1 | 0 |
| 2019 | 3 | 3 |
| 2020 | 2 | 1 |
| 2021 | 1 | 4 |
| 2022 | 3 | 1 |
| 2023 | 2 | 1 |
| 2024 | 1 | 1 |
| 2025 | 0 | 2 |
| 2026 | 0 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Ferromagnetic harmonic elimination method for active matched resistance voltage transformer based on PID adjustment30 Apr 2024US 11,973,337 B2Qujing Power Supply Bureau of Yunnan Power Grid Co., Ltd
- Multifunction single core sensor for ground fault application24 Oct 2023US 11,799,279 B2Schneider Electric USA, Inc.
- Power connector with integrated power monitoring11 Apr 2023US 11,626,698 B2Hubbell Incorporated
- Predictive synchronous rectifier sensing and control6 Sep 2022US 11,437,917 B2Texas Instruments Incorporated
- Transformer and socket assembly for power meter installations16 Aug 2022US 11,415,608 B2TSTM, Inc.
- Power supply unit and circuit breaker30 Jul 2026US 2026/0221758 A1Eaton Intelligent Power Limited
- High-voltage generator and x-ray system3 Jul 2025US 2025/0220798 A1Shanghai United Imaging Healthcare Co., Ltd.
- Magnetic shielding system for a differential current transformer in a circuit breaker to provide shielding at multiple locations6 Mar 2025US 2025/0079071 A1Siemens Industry, Inc.
- Ferromagnetic harmonic elimination method for active matched resistance voltage transformer based on pid adjustment29 Feb 2024US 2024/0072531 A1Qujing Power Supply Bureau of Yunnan Power Grid Co., Ltd
- Multifunction single core sensor for ground fault application19 Jan 2023US 2023/0017320 A1Schneider Electric USA, Inc.
Most cited
By later US patents
- Current transformer arrangement for three-wire three-phase systems to detect the actual current value for controlled DC loads powered via power converters19US 5,202,621 ASiemens AG Osterreich · 1993
- Dual current transformer current sensing method and sensor17US 4,683,513 AWestinghouse Electric Corp. · 1987
- Circuit breaker for disconnecting an electrical apparatus from electrical network8US 6,479,780 B2ABB AB · 2002
- Current transformer for three-phase systems7US 6,313,727 B1Moeller GmbH · 2001
- Current sensor for measuring an electrical current in a circuit having a plurality of electrical conductors7US 7,477,058 B2Corporation Nuvolt Inc. · 2009