Method and apparatus for protecting a load against an overcurrent
US11562865B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 2021 |
| Grant date | Jan 24, 2023 |
| Priority date | — |
| Expiry date | Mar 9, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H1/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A hybrid load protection apparatus (1) comprises a primary power supply path (1A) between input terminal and output terminals (2, 3) and a controllable mechanical switch (5A) connected in series with a primary coil (4A-1) coupled inductively to a secondary coil (4A-2) providing a voltage, UA, corresponding to a current rise speed of the electrical current flowing through the primary path (1A). The voltage, UA, is applied directly to a driver input (IN) of a first driver circuit (6A) to trigger automatically a switch-off of the mechanical switch (5A) within a first switch-off period (Δt1) to interrupt the primary power supply path (1A). A secondary power supply path (1B) is provided in parallel to the primary path (1A) and having a further coil (4B) connected in series with a semiconductor power switch (5B). wherein a second driver circuit (6B) associated with the secondary path (1B) detects an increasing electrical current, I, flowing through the secondary path (1B) caused by the interruption of the primary current path (1A) on the basis of a voltage drop (ΔU4) generated by the further coil (4B) and a non-linear voltage drop (ΔU5) along the semiconductor power switch (5B) applied a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.