To Design Hybrid AC-DC Droop Controller for Load Balancing Applications

Abstract

In the 21st century there are several issues with the current electrical power system, such as production of green house gasses and losses (transmission line and conversion losses) that reduced the efficiency of power system. Currently, DC load demand of applications, such as telecom exchange networking system and electric vehicles (EVs) are increasing. In conventional power system, these loads are connected to main grid through converters. Moreover, diesel generators based backup solutions for telecom exchanges have several disadvantages, such as non-reliable starting of generator in cold weather conditions, maintenance of the generator, and exhaustive fumes. Furthermore, in recent times the use of EVs is increasing rapidly and now work place required to have own EV fast charging docking stations; therefore, in our simulation we consider the DC load of employees EVs along with the DC load of telecom exchange. A hybrid AC-DC micro-grid based on distributed generations is proposed as a suitable solution to reduce the multiple reverse conversions within the telecom exchange. For hybrid AC-DC micro-grid, we develop a droop controlled scheme that manage the power flow between AC and DC electrical networks by enforcing the normalized value of frequency equal to the normalized value of voltage of DC micro-grid. The controller provides, need based power sharing between AC and DC grids and enhance operational reliability of the network. The hybrid AC-DC micro-grid presented in this report is an effective solution to eliminate the excessive voltage conversion problem of telecom exchanges along with an efficient fast charging system for the EVs.