High-Frequency Switching of State-of-the-Art Wide Band Gap Inverters and its Impact on Encoderless Control Schemes

The combination of wide band gap semiconductors and anisotropy-based encoderless control schemes is discussed in this paper. The steep voltage transients of the wide band gap semiconductors and the increasing noise level with higher switching frequencies impact the phase current measurement of an electrical machine. These effects on the measured current signal are analysed, and the influence on the encoderless control performance is illustrated. The phase current measurement and the position estimation of the encoderless control scheme are investigated based on experimental results.