Smart coordinated distribution system control to enable high level penetration of rooftop PVs

This thesis addresses voltage violation problem, the most critical issue associated with high level penetration of photovoltaic (PV) in electricity distribution network. A coordinated control algorithm using the reactive power from PV inverter and integrated battery energy storage has been developed and investigated in different network scenarios in the thesis. Probable variations associated with solar generation, end-user participation and network parameters are also considered. Furthermore, a unified data model and well-defined communication protocol to ensure the smooth coordination between all the components during the operation of the algorithm is described. Finally this thesis incorporated the uncertainties of solar generation using probabilistic load flow analysis.

A supervisory load-leveling approach to improve the voltage profile in distribution network

This paper suggests a supervisory control for storage units to provide load leveling in distribution networks. This approach coordinates storage units to charge during high generation and discharge during peak load times, while utilized to improve the network voltage profile indirectly. The aim of this control strategy is to establish power sharing on a pro rata basis for storage units. As a case study, a practical distribution network with 30 buses is simulated and the results are provided.

Impact of PV units in LV feeders on distribution system reliability

Re-supplying loads on outage through cross-connect from adjacent feeders in a distribution system may cause voltage drop and hence require load shedding. However, the surplus PV generated in some of the LV feeders can prevent load shedding, and improve reliability. In order to measure these effects, this paper proposes the application of Direct Load Flow method[1] in reliability evaluation of distribution systems with PV units. As part of this study, seasonal impacts on load consumption together with surplus PV output power injection to higher voltage networks are also considered. New indices are proposed to measure yearly expected energy export, from LV to MV and from MV to higher voltage network.

Stability analysis of STATCOM in distribution networks

This chapter presents the stability analysis based on bifurcation theory of the distribution static compensator (DSTATCOM) operating both in current control mode as in voltage control mode. The bifurcation analysis allows delimiting the operating zones of nonlinear power systems and hence the computation of these boundaries is of interest for practical design and planning purposes. Suitable mathematical representations of the DSTATCOM are proposed to carry out the bifurcation analyses efficiently. The stability regions in the Thevenin equivalent plane are computed for different power factors at the Point of Common Coupling (PCC). In addition, the stability regions in the control gain space are computed, and the DC capacitor and AC capacitor impact on the stability are analyzed in detail. It is shown through bifurcation analysis that the loss of stability in the DSTATCOM is in general due to the emergence of oscillatory dynamics. The observations are verified through detailed simulation studies.

PAGAT gel dosimeters for dose distribution measurements in the vicinity of high-density implants : a preliminary study

This work examined the suitability of the PAGAT gel dosimeter for use in dose distribution measurements around high-density implants. An assessment of the gels reactivity with various metals was performed and no corrosive effects were observed. An artefact reduction technique was also investigated in order to minimise scattering of the laser light in the optical CT scans. The potential for attenuation and backscatter measurements using this gel dosimeter were examined for a temporary tissue expander's internal magnetic port.

Mapping futures for news: Trends, opportunities and challenges for Scotland

The Mapping Futures of News research and seminar programme, sponsored by the Institute for Advanced Studies in 2009-10, addressed those questions, as well as the many more immediate issues facing the Scottish news industry, such as how to survive the current period of often traumatic transition. This document summarises that work, and identifies: Mapping Futures for News: Programme Report iii • Where the main Scottish print and broadcast news media are in 2010, in terms of circulation and ratings figures; • the key trends currently impacting on Scottish news media; • the responses up to now of government and regulators to assist the Scottish media through the present problems; • the responses of the news media themselves.

Power quality improvements in low voltage distribution networks containing distributed energy resources

In this thesis various schemes using custom power devices for power quality improvement in low voltage distribution network are studied. Customer operated distributed generators makes a typical network non-radial and affect the power quality. A scheme considering different algorithm of DSTATCOM is proposed for power circulation and islanded operation of the system. To compensate reactive power overflow and facilitate unity power factor, a UPQC is introduced. Stochastic analysis is carried out for different scenarios to get a comprehensive idea about a real life distribution network. Combined operation of static compensator and voltage regulator is tested for the optimum quality and stability of the system.

Assessment and application of clustering techniques to atmospheric particle number size distribution for the purpose of source apportionment

Long-term measurements of particle number size distribution (PNSD) produce a very large number of observations and their analysis requires an efficient approach in order to produce results in the least possible time and with maximum accuracy. Clustering techniques are a family of sophisticated methods which have been recently employed to analyse PNSD data, however, very little information is available comparing the performance of different clustering techniques on PNSD data. This study aims to apply several clustering techniques (i.e. K-means, PAM, CLARA and SOM) to PNSD data, in order to identify and apply the optimum technique to PNSD data measured at 25 sites across Brisbane, Australia. A new method, based on the Generalised Additive Model (GAM) with a basis of penalised B-splines, was proposed to parameterise the PNSD data and the temporal weight of each cluster was also estimated using the GAM. In addition, each cluster was associated with its possible source based on the results of this parameterisation, together with the characteristics of each cluster. The performances of four clustering techniques were compared using the Dunn index and Silhouette width validation values and the K-means technique was found to have the highest performance, with five clusters being the optimum. Therefore, five clusters were found within the data using the K-means technique. The diurnal occurrence of each cluster was used together with other air quality parameters, temporal trends and the physical properties of each cluster, in order to attribute each cluster to its source and origin. The five clusters were attributed to three major sources and origins, including regional background particles, photochemically induced nucleated particles and vehicle generated particles. Overall, clustering was found to be an effective technique for attributing each particle size spectra to its source and the GAM was suitable to parameterise the PNSD data. These two techniques can help researchers immensely in analysing PNSD data for characterisation and source apportionment purposes.

Education paths for documentary distribution: DAF, ATOM and the study guides that bind them

An expanding education market targeted through ‘bridging material’ enabling cineliteracies has the potential to offer Australian producers with increased distribution opportunities, educators with targeted teaching aids and students with enhanced learning outcomes. For Australian documentary producers, the key to unlocking the potential of the education sector is engaging with its curriculum-based requirements at the earliest stages of pre-production. Two key mechanisms can lead to effective educational engagement; the established area of study guides produced in association with the Australian Teachers of Media (ATOM) and the emerging area of philanthropic funding coordinated by the Documentary Australia Foundation (DAF). DAF has acted as a key financial and cultural philanthropic bridge between individuals, foundations, corporations and the Australian documentary sector for over 14 years. DAF does not make or commission films but through management and receipt of grants and donations provides ‘expertise, information, guidance and resources to help each sector work together to achieve their goals’. The DAF application process also requires film-makers to detail their ‘Education and Outreach Strategy’ for each film with 582 films registered and 39 completed as of June 2014. These education strategies that can range from detailed to cursory efforts offer valuable insights into the Australian documentary sector's historical and current expectations of education as a receptive and dynamic audience for quality factual content. A recurring film-maker education strategy found in the DAF data is an engagement with ATOM to create a study guide for their film. This study guide then acts as a ‘bridging material’ between content and education audience. The frequency of this effort suggests these study guides enable greater educator engagement with content and increased interest and distribution of the film to educators. The paper Education paths for documentary distribution: DAF, ATOM and the study guides that bind them will address issues arising out of the changing needs of the education sector and the impact targeting ‘cineliteracy’ outcomes may have for Australian documentary distribution.

Overvoltage and overloading prevention using coordinated PV inverters in distribution network

Overvoltage and overloading due to high utilization of PVs are the main power quality concerns for future distribution power systems. This paper proposes a distributed control coordination strategy to manage multiple PVs within a network to overcome these issues. PVs reactive power is used to deal with over-voltages and PVs active power curtailment are regulated to avoid overloading. The proposed control structure is used to share the required contribution fairly among PVs, in proportion to their ratings. This approach is examined on a practical distribution network with multiple PVs.