A Data Selection System Based on Field-Programmable Gate Array in Cascaded Voltage Sourced Converter

There are many identical cascaded power units in voltage sourced converter (VSC) based on cascaded H-bridge or cascaded half-bridge, and the capacitor voltage balance is an important issue in them. The capacitor voltage in every power unit should be monitored on-line, which needs a versatile system to collect capacitor voltage. This paper proposes an on-line data collection system which can be used in VSC based on cascaded H-bridge or cascaded half-bridge. The system not only makes the power unit identical but also makes them isolated from each other and isolated from the main controller. Finally, experiment is carried out verify the system.