Network Loss Analysis of Low-Voltage Low Power DC Microgrids for Rural Electrification

Primary Author: Rabia Khan

Faculty Sponsor: Noel Schulz

 

Primary College/Unit: Voiland College of Engineering and Architecture

Category: Engineering and Environmental Science

Campus: Pullman

 

Abstract:

Principal topic

The topic is “Network Loss Analysis of Low-Voltage Low Power DC Microgrids for Rural Electrification”. Millions of people around the globe are suffering  from energy poverty, particularly the inhabitants of Africa  and South-East Asia. Electrification through national grids is cost-prohibitive with limited power generation sources in the  third world countries. The low voltage, low-power islanded DC microgrids are a practical option for rural electrification.

 

Method

In this research work, the detailed network loss analysis of four different microgrid architectures is performed using the modified Newton-Raphson power flow for DC systems. These architectures include, 1) Centralized generation centralized storage (CGCS), 2) Centralized generation distributed storage (CGDS), 3) Distributed generation centralized storage (DGCS), and 4) Distributed generation distributed storage (DGDS), which are implemented with both radial and ring interconnection schemes using time-varying load demand and PV generation.

 

Results/implications

Comparative performance analysis of these architectures is done using the modified Newton-Raphson power flow method at different low-voltage levels and conductor sizes. The DGDS architecture with ring interconnection is the most efficient and reliable with an advantage of scalability, usage diversity, and mutual resource sharing capability. However, ring interconnection requires extra conductors, which increase the cost. So, a tradeoff between conductor size, voltage level, cost, interconnection scheme, and reliability is to be made while selecting the components for the microgrid architecture. The efficiency of systems is higher for conductors with lower AWG sizes but it is more expensive. So, trade-off between conductor size, voltage level, cost, interconnection scheme, and reliability is important.