Microprocessor-based DC motor drive with spillover field weakening

A microprocessor-based speed control scheme for a separately excited DC motor fed from a DC source, which incorporates both armature-voltage control and spillover field weakening to provide smooth and precise control from standstill to speeds well above the base value, is described. Armature-current limitation during transient operation is achieved using an interventionist system external to the microprocessor controller, thereby simplifying considerably the overall system design. Experimental results obtained from a prototype 5 kW drive are presented to illustrate the excellent dynamic behavior of the scheme.<
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