Modulation policy for modular multi-level converter
US9787219B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 2014 |
| Grant date | Oct 10, 2017 |
| Priority date | — |
| Expiry date | Jun 4, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M7/5395
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A modulation policy for a modular multi-level convertor, determining a switching state of each submodule by combining the current direction of each bridge arm and the capacitor voltage order of the submodules based on a carrier stacking method. The beneficial effects of the modulation policy are that: each phase only needs a modulation wave and N carriers, given N submodules of each upper bridge arm or lower bridge arm of the modular multi-level convertor; the modular multi-level convertor can output N+1 levels without carrier phase shift; N devoted submodules of each phase are guaranteed at any time; and the submodules' capacitor voltage balancing can be controlled without a closed-loop control policy. The modulation policy facilitates adjustment of the modular multi-level convertor voltage and power class, has unlimited number of levels, has a high precision control algorithm, is easy to realize in engineering and saves software and hardware resources.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.