Dynamic modelling of an industrial microgrid

Abstract

With a decentralized approach to power system development gaining traction in both developed and under-developed countries, the realization of the next generation of power distribution network is identified as the Smart Grid. A Smart Grid utilizes all the current advances made in power electronics, renewable generation, and communication to provide a resilient, environmentally friendly network without the large scale infrastructure needed in centralized generation networks. A key part to the realization of the Smart Grid is the microgrid, which is a combination of various distributed energy resources and loads connected to the same point of common coupling. The microgrid can be situated in an industrial facility, commercial park or residential area and provides the owner with a resilient energy source, reliable power quality, economically beneficial operating options and an environmentally friendly footprint. Microgrid design and implementation vary vastly and hence a lot of possible research and development opportunities are available. To better understand and improve dynamic response within a microgrid, which is one of the areas of development, a site-specific representative model can be created. The analysis and improvement of dynamic response within a power system ensure proper operation throughout its service lifetime, optimizes maintenance focus and minimizes production loss due to unnecessary power dips and outages. Aconcise modelling approach, documented in this dissertation, provides the necessary background, design, verification and validation processes to create such a model. This is done by combining research on different microgrid standards, compositions, power quality events and control methods, with operational field data obtained from the site being modelled. Results obtained emphasized the improvement on islanded network voltage and frequency stability, through improved generator and energy storage control. Operational limits and improvements to system operation philosophy were identified and tested. Overall this representative model provides a platform to analyse microgrid performance, identify possible improvement opportunities and test future development plans without taking the financial risk of blindly deploying such practices on site, making it a valuable asset.