TH

T.G. Hailu

12 records found

Authored

This paper reviews the currently available dc micro-grids and dc grids. Currently, commonly existing and proposed dc microgrids are designed to provide sufficeint energy during system disturbance as in ac grid and, are mainly voltage stiff systems. It also compares the voltage ...

This paper describes the behavior of voltage weak DC distribution systems. These systems have relatively small system capacitance. The size of system capacitance, which stores energy, has a considerable effect on the value of fault currents, control complexity, and system reliabi ...
This study evaluates the dynamics of DC microgrids (DCMG) with the integration of voltage dependent demand response (VDDR). Previous work evaluates price prediction models for grid operators to estimate local price as a demand side management (DSM) technique. VDDR has been propos ...

Distributed Generation has created the need for new types of smart dc grids developments. The multiple generation sources, bi-directional power flow, power flow time co-ordination and management bring significant benefits as well as challenges for current ac electrical grids a ...

This paper introduces a new power system that can be implemented on all levels by using the bottom-up approach of system design. It is based on orthogonal power flow at different frequencies. The power exchange between different elements of the grid as well as the additional feat ...
DC microgrids can connect directly dc renewable energy sources with increasing amount of dc loads. In this paper it is looked for possible architectures for integrating PV panels into dc microgrids, by means of microconverter strings. Three topologies are considered, featuring on ...
The traditional ac power system is challenged by the increased amount of distributed energy resources. Enormous changes and investments are necessary in order to achieve an ac smart grid capable of coping with the challenges introduced. In dc, solutions seem to be more straightfo ...