Efficiency-optimized speed control system for a separately-excited DC motor

A systematic design method for efficiency-optimized speed control system synthesis is proposed based on the improved optimal regulator theory. The system under consideration is a separately excited DC motor system. The improved optimal regulator theory is applied to this system effectively and the systematic design procedure can be realized. The ratio of the armature current and the field current that gives the maximum efficiency is analytically derived, and the error term of the current ratio is included in the performance index. The desired signal and the disturbance signal are assumed to be step functions. The simulation results are detailed and discussed. The effect of the feed forward components on the system performance is presented.