Intelligent database design for microgrids in low voltage distribution systems-I GUI and database design

• Main Author: Ng, Pei Fen
• Other Authors: Wang Peng
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Electric power::Auxiliaries, applications and electric industries
• Online Access: http://hdl.handle.net/10356/61353
• Institution: Nanyang Technological University

Generation of electricity is mostly through the combustion of fossil fuels such as natural gas, petroleum and coal. Among these fossil fuels, coal is the largest source of fuel consumed for generating electricity globally. Many millions of years is required for coal to be formed thus it cannot be replenished easily once it is combusted. The rate of consumption of coal to generate electricity is significantly more rapid than the rate of fossil fuels formation. During the combustion of fossil fuels, harmful pollutants are being produced, for instance, carbon dioxide, sulphur dioxide and methane. [50] These harmful pollutants contribute to global warming. Global warming is a worldwide environmental problem as it affects the bio-diversity and homes of millions of people. Climatic change is the result of the significant increase in atmospheric concentration of greenhouse gases. Climatic change can lead to consequences such as increasing cases of heat-related illness, endangering wildlife like polar bears and rising of sea level that would trigger natural disasters leading to individual losing their homes. [51] Due to extensively use of electricity in this contemporary society, there arises a need to seek for alternative energy sources, if at all possible renewable resources such as wind and solar. Renewable resources are preferable as it reduces the usage of fossil fuels. [50] Renewable resources are wind, solar, biomass, hydro and geothermal. Renewable resources like solar, wind and hydro energy do not pollute the air and are available at no cost. Unlike biomass, these renewable resources do not emit air pollutants since combustion is not required. Solar power has its own limitations, for instance, inconsistent input generating rate by reason of weather conditions or shading of cloud.With the increasing application of renewable resources in low voltage distribution systems, microgrid is being introduced. [49] Microgrid is located in areas close to customers so that power supplied is of desired frequency and voltage level. [13] In terms of generators capacity, conventional power plants are a lot larger than microgrid. Microgrid is interconnected to the main grid and is the combination of producing, accumulating, distributing and providing energy to controllable loads. Microgrid can be operated either in autonomous or grid-connected mode. [13] [31] Microgrid can operate autonomously when the linkage in between the microgrid and main grid are severed. This capability is introduced to reduce the consumption of non-critical loads when there is a disruption of energy supplied by the main grid. While waiting for the main grid to get back online, the microgrid will continue to supply electricity to its site. The connection between the microgrid and the main grid will be automatically established when the main grid is back in commission. Microgrid will recharge its energy storage so it could provide energy to site another time when main grid fails. [49] [31] Generating resources for microgrid can either be fuel cells or renewable resources, for instance, wind energy and solar energy. When there is an unexpected surge in the load demand, microgrid facilitates the main grid in providing voltage support and reducing the stability complication. Reliability and security of the power grid is enhanced and the quality of power produced is increased. [31] With microgrid, environmental pollution is also being reduced.