Calculation of field forcing in a two-zone dc drive

This paper gives the analytic conduction for the calculation of a field forcing in a two-zone dc drive based on the analysis of field weakening and strengthening processes. The needed field forcing coefficient depends on two generalized factors, the ratio of an electromagnetic time constant to a base (mechanical) time constant and an equivalent retarding torque. When the realization of that coefficient is impossible the evaluation of quick-response reducing is given. In that case transient time of field strengthening is increased and a time difference may be equal to three base time constants.