Method for performing instantaneous protection in a trip unit
US6078489A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1998 |
| Grant date | Jun 20, 2000 |
| Priority date | — |
| Expiry date | Aug 20, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/0935
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of performing instantaneous protection in a trip unit is presented. The electronic trip unit includes a microcontroller and associated ROM having trip unit application code, e.g., main functionality firmware, including initializing parameters, and boot code, stored therein and EEPROM having operational parameter code stored therein. An instantaneous protection algorithm (program) stored in the memory of the trip unit has a `WAIT` state and a `RUN` state. In the RUN state samples of the sensed current that classify as points that are accumulated in a point register. Accumulation of a determined number of points qualifies as a peak. These peaks are accumulated in a peak register. If a point is not detected within a determined time period, then the count of peaks accumulated in the peak register is decremented, thereby provided a cooling function. When the count in the peak register exceeds the sensor limit a signal is generated by the microcontroller to initiate the trip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.