Potential of RC-IGBT in Full Size Converters for Wind Energy Application

Abstract:
Bi-Mode Insulated Gate Transistors (BIGTs) are a new class of power semiconductors, which integrate the functionality of IGBT and free-wheeling diode in one chip [1]; [2]. The advantage of the BIGT concerning output power and power cycling stress depends strongly on the application [3]; [4]; [5]; [6]. The BIGT has the main advantage in applications with low fundamental frequency and high modulation degree [5]; [6]. An application where the BIGT is advantageous is the full size converter for wind energy especially the generator side converter due to the low output frequencies of the generator in combination with the rectifier operation mode. In this paper the advantage of the BIGT in this application will be demonstrated. The total number of cycles including mission profile and fundamental frequency cycles were counted using the Rainflow algorithm. To count the fundamental frequency cycles only the maximum and minimum temperature within one period of the fundamental frequency were extracted. The investigation was done for a real wind speed over time profile.