Abstract

Reliability and fault tolerant operation are key aspects in high power drives, specially when these drives are used to operate critical loads, as downhill conveyors. This paper presents a solution for the operation under internal fault of high power regenerative Cascade Multicell Converter, which allows to operate temporally in normal conditions or to turn off the equipment in a controlled way. Previous works have shown that it is possible to reduce the effects on the load due to internal faults by modifying the phase-shift between the output voltages. The proposed method uses the additional degree of freedom given by the controlled dc-link voltage of the PWM rectifiers, to increase the operation range, even reaching non-fault operation. ©2008 IEEE.