Protection of Dc-Micro grid From Multiple Line and Ground Faults
Srihari Mandava1, Abhishek Gudipalli2, Pradeep Reddy Ch3

1Srihari Mandava, School of Electrical Engineering, VIT University, Vellore, India.
2Abhishek Gudipalli, School of Electrical Engineering, VIT University, Vellore, India.
3Pradeep Reddy Ch, School of Computer Science and Engineering, VIT-AP University, Amaravati, India.

Manuscript received on 02 June 2019 | Revised Manuscript received on 10 June 2019 | Manuscript published on 30 June 2019 | PP: 3120-3126 | Volume-8 Issue-8, June 2019 | Retrieval Number: H7268068819/19©BEIESP
Open Access | Ethics and Policies | Cite | Mendeley | Indexing and Abstracting
© The Authors. Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC-BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Abstract: In this paper, a protection scheme for the microgrid system on low voltage side is proposed as a dc system’s protection techniques are relatively unexplored as compared to the ac systems, whereas the ac systems face numerous problems like frequency matching, reactive power violation and instability. The core objective of the project is to eliminate the faulty section (in the event of occurrence of a fault) promptly while keeping the healthy sections functioning unaltered. In this work, a segment controller exists in the loop type. This has master and slave controllers continually monitoring the segments of grid comprising of semiconductor bidirectional switches and snubber circuits. A master controller is used for all the three segments that monitors the difference between the input and output currents and in the event of the difference being greater than the acceptable limit, instructs the slave controllers to take the required action and eliminate the section under fault. Both line as well as ground faults have been tested on all the sections separately as well as together and perspicuous analysis has been done. It is inferred that the protection scheme is able to isolate the faulty section in a short time and after the faulty section has been eliminated other sections regain their stable voltage and current limits. The protection scheme can identify faults of the grid irrespective of the fault current’s amplitude or the power supply’s feeding capacity. The simulations are designed and verified using MATLAB Simulink 2015a software.
Keyword: Bidirectional switches, fault, Low Voltage DC Systems, Microgrid.
Scope of the Article: Microwave Photonics.