A Control Strategy for a Matrix Converter under a Large Impedance Power Supply

This paper proposes a control strategy for a matrix converter with an input power supply such as generator. Currently, applications for grid connection have been considered such as micro-gas turbines, wind power systems, engine generators and so on. However, very large impedance power supply such as the generator has not been sufficiently examined. Especially the PM generator which is used in various applications has large synchronous reactance. Terminal voltage of the generator is not stable due to resonant phenomena between synchronous reactance and an input capacitor. Therefore, the induced electromotive force (e.m.f.) in the generator is estimated using a band pass filter (BPF). In addition, stabilization control on a rotating frame is also proposed for the input terminal voltage. In addition, this paper suggests an optimum input power factor control because the output voltage is smaller than the output voltage command when a conventional power factor control is used. By using the stabilization control, the input current THD of 4.2% is obtained through experimental results. Moreover, the validly of the optimum input power factor control is also confirmed by the experimental results.