A current regulated switching strategy with auto-restarting ability during power grid interruptions for matrix converter

Due to the properties of the matrix converter, the pseudo DC-link will provide with three different types of voltage. By suitably selecting switching pattern, the output current ripples are obviously reduced and unity power factor can be achieved. Using the switching strategy, the immune ability against disturbances is promoted. Thus power quality can be improved. In addition, to maintain the working ability of the control circuits and DSP under power grid interruptions is also investigated. When the power grid has returned to normal condition, the motor will restart automatically. The matrix converter is used to drive a PMSM servo motor. All the control loops, including the switching strategy, current-loop, and control law, are implemented by TMS320LF2407A digital signal processor. The hardware circuit is very simple. Several experimental results are shown to validate the theoretical analysis.