Design of battery supplemented micro - STATCOM and development of associated control algorithms to mitigate power quality issues in low voltage networks

Abstract

Power Distribution Networks are evolving with the rapid penetration of distributed generators and introduction of concepts such as micro grid based Smart Girds. Distribution automation devices and solar PV generators in the present-day power systems makes power distribution networks more and more active. Assurance of a power supply with better power quality for a distribution customer is becoming a challenging task with the penetration of various loads inspired by power electronic concepts. And also, with the enormous penetration of solar PV generators to power distribution networks, bi-directional power flow makes it more challenging. As most of the planning studies carried out to improve Medium Voltage (MV) Networks to address these challenges, less attention has paid for the monitoring of power qualities at Low Voltage (LV) Distribution Networks. This research identifies a vital requirement to improve power quality at the leaf level of LV distribution network and presents a combined solution for most predominant power quality issues exist in LV distribution network. This thesis presents a Micro-STATCOM based solution to address power quality issues by under voltage regulation, over voltage regulation, harmonic mitigation and improving system power factor in LV distribution system. Development of Micro-STATCOM based model with DC power source is presented in order to mitigate major power quality issues exists in the modern LV distribution systems. Performance of the Micro-STATCOM model has evaluated with response time for voltage regulation, resolution of voltage regulation and level of reduction in Total Harmonic Distortion (THD%). Developed Micro-STATCOM was then integrated into modified IEEE 13 Distribution Bus System in order to observe the mitigation of power quality issues. Results obtained by mitigation of each power quality issues in the distribution network are discussed in this thesis. Potential applicability of developed Micro-STATCOM in the practical low voltage distribution networks and other areas are discussed and recommendations are made for the selection criteria to integrate Micro-STATCOMs in LV distribution Systems.