Abstract :
The paper will describe the structure, philosophy and hierarchy of the control strategy used in several applications of medium voltage drives. The "building block" is a standard Robicon perfect harmony drive, which consists of a multi-level VSI topology composed of several H-bridges "cells" in series for each phase, to produce the desired output voltage. The standard single perfect harmony drive presents already an architecture in line with fig. 3.1 of the PARI 676 guidelines. There are 5 control levels: application control, converter control, Switching control, cell control, hardware control. This structure has proved to be well suited for all applications requiring the operation of a single drive. Given the topology of the perfect harmony and the cell based control structure, even in the basic single drive configuration, some redundancy is built in the power section and cell control, which allows operation in degraded conditions.
Keywords :
electric drives; invertors; switching convertors; Robicon perfect harmony drive; application control; building block standard; cell control; control architecture; converter control; hardware control; large MV drives; medium voltage drives; multilevel VSI topology; power section; Automatic control; Availability; Control systems; Distributed control; Drives; Programmable control; Redundancy; Stators; Torque control; Voltage control;
