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Abstract: The direct current (dc) technology has gained significant momentum and widespread acceptance in modern distribution systems due to the high penetration levels of dc loads and dc-based distributed generators (DGs). This thesis presents a detailed analysis, performance comparison, and design guidelines of two different positive feedback islanding detection schemes in dc distribution systems. Then, the work continues to investigate the interaction dynamics of a dc distribution system characterized by a high penetration level of CPLs, and DGs equipped with positive feedback islanding detection schemes. Further, the impacts of supplying dynamic loads from a common dc bus are addressed for different modes of operations. Furthermore, the importance of the detailed modeling of source-side dynamics in a hybrid ac/dc system has been shown. Moreover, different stability enhancement strategies are proposed to enable effective integration of dynamic loads and wind energy resources into dc systems, considering various installation scenarios. The investigated systems consider typical industrial parameters and device constraints to provide practical analysis. Throughout the thesis, detailed time-domain nonlinear simulations under the Matlab/Simulink environment, hardware (control)-in-loop real-time simulation studies, and experimental laboratory results validate the analytical results.