Process for determining the loading condition of a diode rectifier of a frequency converter
US7489124B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 21, 2005 |
| Grant date | Feb 10, 2009 |
| Priority date | — |
| Expiry date | Feb 8, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M7/062
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A process is disclosed for determining the charging state of a diode rectifier (4) of a frequency converter (2) connected to a supply grid (18). According to the invention, a rectifier current (iZKnetz) is determined on the basis of a measured intermediate circuit voltage (UZK) and of measured motor currents (i1, i2, i3), and the rectifier current (iZKnetz) is compared with a predetermined threshold value, any upper deviations are stored and the frequency of the deviations within a predetermined time period, which represents a measure of the charging state, is determined. This permits a frequency converter (2), which is connected to a supply grid (18) and has a diode converter (4) on the side of the grid, to determine without difficulty the charging state of its diode rectifier (4) after temporary grid voltage breakdowns, so that the diodes of the diode rectifier (4) need no longer be oversized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.