Apparatus and methods to reduce current transient during power mode transfer in uninterruptible power supply
US11201497B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 2019 |
| Grant date | Dec 14, 2021 |
| Priority date | — |
| Expiry date | Nov 10, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY04S20/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus and methods to reduce current transient during power mode transfer in uninterruptible power supply (UPS). The disclosure provides a zero-cross detection based phase width modulated (PWM) element (E3). The element (E3) is configured to delay activation of a PWM modulator, by delaying a PWM start command for a first delay time (Tdz), wherein the first delay time is the time between receiving a static switch command to the time when a positive sequence component of a phase load current crosses zero. The element (E3) is further configured to delay the activation of the PWM modulator for a second delay time (Tdi) after the end of the first delay time (Tdz), by delaying the PWM start command for the second delay time, wherein the second delay time is based on a power factor of load connected to the UPS.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.