In a monography results of theoretical and experimental researches of non-salient pole DC machines with asymmetrical compensating windings on stator are brought. Features of the optimal designing of some DC machines types are considered. It is shown that new method of electromagnetic excitation of DC machines increase efficiency, results the improvement of weight-dimension factors, considerably reduce the specific consumption of copper wire. A book is intended for technical and engineering employees specialized in calculations, constructing, research of DC machines, for research workers in electromechanical industry, for graduate students and students of electromechanical and electrical engineering specialties.