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We define Poisson process models for outage and restore processes in power system resilience events in terms of their rates. These outage and restore processes easily yield the performance curves that track the evolution of resilience events, and their area, nadir and duration are standard resilience metrics. We derive explicit and intuitive formulas for these metrics for mean performance curves in terms of the model parameters; these parameters can be estimated from utility data. This clarifies the calculation of metrics of typical resilience events, and shows what they depend on. We give examples of the metric formulas using a typical model of transmission system outages with lognormal rate restoration, and also for constant rate and exponential rate restorations. We give similarly nice formulas for the area metric for empirical power system data.

We quantify resilience with metrics extracted from the historical outage data that is routinely recorded by many distribution utilities. The outage data is coordinated with wind data to relate average outage rates in an area to wind speed measured at a nearby weather station. A past investment in wind hardening would have reduced the outage rates, and the effect of this on metrics can be calculated by sampling a reduced number of the historical outages and recomputing the metrics. This quantifies the impact that the hardening would have had on customers. This is a tangible way to relate an investment in wind resilience to the benefits it would have had on the lived experience of customers that could help make the case for the investment to the public and regulators. We also quantify the impact of earlier or faster restoration on customer metrics and compare this to the impact of investment in hardening. Overall this is a new and straightforward approach to quantify resilience and justify resilience investments to stakeholders that is directly driven by utility data. The approach driven by data avoids complicated models or modeling assumptions.

This paper discusses the resilience of power systems in the context of other interdependent critical infrastructure systems. Potential sources of disruption are explained, and their interconnected impacts are discussed. The theoretical frameworks for assessing reliability and resilience across electricity, gas, water, telecommunications and transport networks are presented, and a new approach is proposed for integrating these approaches into a unified resilience assessment framework. The CIGRE C4.47 resilience definition is generalised, and promising new methodologies are explored.

This thesis was scanned from the print manuscript for digital preservation and is copyright the author. Researchers can access this thesis by asking their local university, institution or public library to make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.

Transmission line outage rates are fundamental to power system reliability analysis. Line outages are infrequent, occurring only about once a year, so outage data are limited. We propose a Bayesian hierarchical model that leverages line dependencies to better estimate outage rates of individual transmission lines from limited outage data. The Bayesian estimates have a lower standard deviation than estimating the outage rates simply by dividing the number of outages by the number of years of data, especially when the number of outages is small. The Bayesian model produces more accurate individual line outage rates, as well as estimates of the uncertainty of these rates. Better estimates of line outage rates can improve system risk assessment, outage prediction, and maintenance scheduling.

This paper develops a comprehensive framework of Area Angle Monitoring (AAM) to monitor the stress of bulk power transfer across an area of a power transmission system in real-time. Area angle is calculated from synchrophasor measurements to provide alert to system operators if the area angle exceeds pre-defined thresholds. This paper proposes general methods to identify these warning and emergency thresholds, and tests a mitigation strategy to relieve the area stress when the area angle exceeds the threshold. In order to handle the limited coverage of synchrophasor measurements, this paper proposes methods to estimate phase angles for boundary buses without synchrophasor measurements, which extends the application of AAM. AAM is verified for a power transmission area in the Western Electricity Coordinating Council system with both simulated data and synchrophasor measurements recorded from real events. A utility deployment to test the framework for monitoring area angle with live-stream and recorded synchrophasor data is described., Comment: 8 pages, 17 figures

Observed transmission line outage data is grouped into successive generations of events. The empirical distribution of the number of generations in the cascades follows a Zipf distribution that implies the increasing propagation as cascades progress. The slope of the Zipf distribution gives a System Event Propagation Slope Index (SEPSI). This new metric quantifies the cascade propagation, varies as expected, and determines the probabilities of small, medium, and large cascades.

Most students in Australia now make a contribution towards the cost of their higher education, although not all students are paying the same proportion of the costs of their courses. Even though the Australian Government has tightened up its fee-paying regulations, a loophole remains for some overseas-born students who have permanent-resident status but who may leave after completion of their course. Copyright. Monash University and the author/s

In May 1995 the Government announced new rules designed to restrict educational benefits to those who have demonstrated a long tem commitment to Australia. However, these rules miss their target and will cause considerable administrative and personal inconvenience. Copyright. Monash University and the author/s

A large proportion of students competing for first year university places are selected on the basis of their Year 12 performance according to the Equivalent National Tertiary Entry Rank (ENTER). The ENTER ranks each student in relation to all other students. Year 12 students strive to achieve the highest ENTER possible, in order to optimise their choice of university and course. Students from Government schools produce lower ENTERs (on average) than students from other types of schools. One also reads, from time to time, that high ENTERs are not a good predictor of university success. This paper examines the situation at the start of the twenty-first century, using Monash University as a case study. Copyright. Monash University and the author/s

No progress has been made over the past decade in improving equity of access to higher education for young people from low socio-economic backgrounds. New evidence indicates that both family income and cultural factors explain this situation. The cultural factor is particularly strong for boys from blue collar backgrounds. Current Government equity policy ignores these findings. Copyright. Monash University and the author/s

Shortages of professional IT workers are a major cause of concern for the future of Australia’s IT industry. Though there has been a sharp increase in IT training at Australia’s universities during the 1990s, more than half of this increase has been directed at overseas full-fee paying students. Only a minority of these full-fee paying students are utilising the new opportunities for permanent residence available since mid-1999. The appropriate policy response should be to increase IT training places for local students. Copyright. Monash University and the author/s

Statements by Pauline Hanson about Asian immigration have not affected enrolments of Asian students in Australian educational institutions. Indeed, enrolments grew from 1996 to 1997. In contrast, the Asian currency crisis has reduced enrolments, especially in short-term language courses. Enrolments in higher education are much less affected. Copyright. Monash University and the author/s

Current equity plans for Australian higher education are based on research which claims that non-English-speaking-background (NESB) people are under-represented in the universities. The problem is held to be particularly acute for recent arrivals and equity plans are currently in place to rectify this situation. The background research, however, is inaccurate. Young NESB people have higher participation rates than English-speaking-background people. In some cases, such as the Chinese, Korean and Vietnamese speakers, the level of participation is striking. Copyright. Monash University and the author/s

Universities have been under pressure to diversify their funding base and one of their responses has been the more vigorous recruitment of fee-paying overseas students. Although they now comprise eight per cent of all university enrolments, there have been few changes in the distribution of overseas students by country of origin or by university between 1989 and 1996. Much of the overseas student expansion has gone into the business field, the choice of about 48 per cent of overseas students. Copyright. Monash University and the author/s

Article is incorrectly labelled Volume 1 Number 2 Copyright. Monash University and the author/s

A Senate committee is currently reviewing the level of student income support. Using previously unpublished data, this article shows that the proportion of full-time higher education students who are Youth Allowance recipients is low and, in the case of young students, has fallen since 1997 Copyright. Monash University and the author/s

In mid-1998 the Australian Government implemented a new payment system for student financial assistance in which the Youth Allowance replaced Austudy. An analysis of recipient rates as of September 1998 showed that only 37 per cent of full-time undergraduates were accessing the payment. It is argued that the severity of the means test is such that it excludes students from households with modest incomes and that this is contributing significantly to their low participation rates in higher education. Previous article ends on p. 19 Copyright. Monash University and the author/s

No description provided Copyright. Monash University and the author/s

Some students' parents appear to be securing government subsidies for their children's education because of their capacity to avoid the means test on Austudy. There is evidence for this in elite private schools and in tertiary institutions. Some wealthy overseas born parents may have an option to manipulate the migration program to obtain HECS places and Austudy for their offspring. Copyright. Monash University and the author/s

Drawing on data from Australia’s 1996 and 2001 Census of Population and Housing, this paper enumerates and examines the distribution of Victoria’s population according to people’s religious identification. The number of both Christians and non-Christians increased over this five-year period, but Christians’ proportion of the Victorian population declined. Patterns of religious residential concentration have remained largely the same, but the degree of concentration has increased for Jews in Caulfield and Muslims in the northern suburbs. Pagination on item is incorrect Copyright. Monash University and the author/s

The Australian university sector has grown rapidly over the past two decades but the acceleration in numbers of students has far exceeded that of staff. Moreover numbers of staff in administration and support roles have grown more sharply that those of teaching staff. The key reason for the disproportionate growth in administrators is the way in which federal governments of both persuasions have introduced polices that require more and detailed accountability from universities. Copyright. Monash University and the author/s

The Government's proposals for change to Austudy means testing could save it money but they are likely to affect some university students adversely. The impact of the change on higher education is not obvious from the material the Senates Estimates Committee is receiving to help its decision-making. Copyright. Monash University and the author/s

The Coalition Government has recently asserted that too many young Australians are training to become professionals and not enough as traditional tradespersons. By implication, there is a surfeit of young professionals. This article challenges these assertions. It shows that there has been a substantial increase in the employment of professionals since the Coalition came to power in 1996. Yet over the same period, the number of domestic students in Australian universities at the undergraduate level has hardly increased at all. All of the increase in professional training at the undergraduate level in Australian universities has been directed at overseas students. Partly as a consequence, there has been a rapid increase in the intake of professional migrants to satisfy employer needs. The article concludes that there is a need for more training of domestic undergraduate students, not less. Copyright. Monash University and the author/s

Australia's recent radical deregulation of specialist' temporary-entry visa rules is reviewed from the perspective of experience in the United States. Copyright. Monash University and the author/s

The rapid growth in demand for university-trained personnel over recent years has mainly been filled by growth in the skilled migration program. The authors argue that more domestic students should be trained. The Coalition Government does not agree. It claims that ‘unmet demand’ from prospective university students has been met and, anyway, that additional subsidised places are to be created. This article scrutinises these claims and concludes that they are not correct. Copyright. Monash University and the author/s

More than 55 per cent of students commencing higher education in 1995 were women. Nonetheless, some of the targets set in equity programs continue to label women as 'disadvantaged' and the government is still seeking to increase numbers of women in 'non-traditional' courses and postgraduate study. Meeting these targets will lead to an even greater gender imbalance unless men replace women in areas of study which are traditionally female. Gender access and participation differences at the micro level may be caused by choice or factors external to universities, rather than by systemic discrimination within the higher education sector. Copyright. Monash University and the author/s

Concern has been expressed about alleged Asian domination of student entry into elite health courses. This article analyses the latest university enrolment statistics. It shows that such concerns are only partially correct for medicine but justified in the case of dentistry and optometry. Copyright. Monash University and the author/s

Information on the class characteristics and financial support of commencing Monash students indicates that students from moderate to low income families will face increasing difficulties in accessing university places. Copyright. Monash University and the author/s

Many authors and policy makers assume that girls and women are a disadvantaged group in education. This was once true. By the 1990s, however, female students had not only caught up with males; on a number of indicators they had surpassed them. This success in overcoming disadvantage in higher education should transfer to overcoming some of the barriers encountered by women In the workforce. Copyright. Monash University and the author/s

In order to achieve a fair representation of all young Australians in the higher education system, the Australian Government has designated a number of equity categories. However, little progress has been made with the most important of these, that is people from low socio-economic-status backgrounds. Copyright. Monash University and the author/s

When power grids are heavily stressed with a bulk power transfer, it is useful to have a fast indication of the increased stress when multiple line outages occur. Reducing the bulk power transfer when the outages are severe could forestall further cascading of the outages. We show that synchrophasor measurements of voltage angles at all the area tie lines can be used to indicate the severity of multiple outages. These synchrophasor measurements are readily combined into an "area angle" that can quickly track the severity of multiple outages after they occur. We present a procedure to define thresholds for the area angle that relate to the maximum power that can be transferred through the area until a line limit is reached. Then in real time we would monitor the area angle and compare it to the thresholds when line outages occur to determine the urgency (or not) of actions to reduce the bulk transfer of power through the area. The procedure also identifies exceptional cases in which separate actions to resolve local power distribution problems are needed. We illustrate the thresholds and monitoring with the area angle across several states of Northwestern USA.

Presentation given October 19, 2012 as part of the i4Energy seminar series

To investigate models, sensing systems and other means for detecting, in advance of failure, the degradation of the concentric neutral conductors of underground power distribution cables.

Report prepared for CIEE and California Energy Commission

This paper presents an overview of challenges associated with intermittent and distributed electric generation relative to the goals for renewable integration in California, framed in terms of a coordination problem at multiple scales in both space and time.

In many countries, market-like mechanisms have been introduced into the traditionally public domain of higher education. The main drive for this has come from the government’s realisation that it has only limited steering capacity through planning and control mechanisms (Van Vught 1997). Many governments aim at enlarging the adaptive capacity, flexibility, efficiency and quality of higher education. In short, governments took a step back and, by implementing market-like policy instruments, they hoped to make higher education institutions more accountable and responsive to the needs of society. These new steering strategies have led to developments such as deregulation (by providing more autonomy to institutions); competition (between public and private institutions for student places and research funds); the implementation of quality assessment; and the introduction of or raising of customer (tuition) fees (Dill 1997).

The reliability of electric transmission systems is challenged by the recent deployment of intermittent energy sources and market developments, which have resulted in a large amount of power volumes being transmitted over long distance and higher uncertainty in the system operation. Wide-area blackouts and cascading events in the past decades suggest that the system is operating with reduced safety margins. Although such large blackouts are rare events, they have the potential to result in massive disruptions of the electricity service. This dissertation focuses on the estimation and quantification of the vulnerabilities and risk of cascading failures in the power systems and on the interdependent infrastructures. To this aim, the original research activities include the development and validation of computational tools for analyzing and simulating the failure behavior in power systems, the evaluation of protective measures for mitigating the cascading failures and the quantification of the impact of the interdependent infrastructures and of economic operations on the security of the power grid. In the first part of the thesis, we focus on the development of cascading failure analysis models. A DC power flow based cascading failure analysis is introduced, the linear nature of DC power flow leads to efficient computation and applicability to large-scale systems. The model considers the most common failure propagation mechanism, i.e., a cascade of overloaded lines, and the automatic system interventions such as frequency control. The voltage profile of buses and reactive power have significant impacts on the system conditions, and by disregarding their effects, the underlying assumptions in the DC power flow method may provide overly optimistic results and underestimate the risk of cascading failures. To cope with that, an advanced AC power flow cascading failure model is developed. It captures the voltage and reactive power problems in the cascade and implements the remedial actions such as under frequency load shedding. To find a compromise solution between the computationally expensive AC power flow and the approximate DC power flow, a linear implicit AC power flow method is applied in the cascading failure analysis. Statistical comparisons demonstrate that linear AC power flow provides a good approximation of the AC power flow solution and its computational time does not increase significantly compared to the DC power flow. In the cascading failure analysis, many parameters are involved. It is critical that these parameters are calibrated appropriately when the analysis is applied to a specific system. Therefore, an algorithm is developed for the calibration and the validation of the cascading failure analysis based on meta-heuristic optimization. The model parameters are optimized through minimizing the differences between the simulation results and the historical blackout data. The calibrated model is able to capture the important statistical features of cascading failures, e.g., the distribution of blackout size and number of line outages. In the second part of the thesis, we apply the developed cascading failure analysis on the risk assessment of cascading failures in power systems from three perspectives: first, with the aim of mitigating the consequences of cascading events, a heuristic decision support system is developed to alleviate line overloads by redistributing power quickly and adequately during emergency. The multi-objective decision making is based on the sensitivities of the overloaded lines with respect to power shifts among inter-subnetworks and on the time required to complete them. Second, failures in the electric power infrastructure not only cause the disruption of the power supply but also result in losses in productivity across other dependent industries. To address the societal impact of the blackouts, we uniquely integrate the cascading failure analysis for the electric network with a multi-regional, multi-industry interdependency model to quantify the short-term economic impacts of electric power disruption. The societal impact quantification provides an additional metric for measuring the vulnerability of a system and the criticality of components in the infrastructure. Third, the impact of the day-ahead planning and economic operation on the power supply security is investigated. To achieve this, we model the two main market-clearing models: the decentralized self-scheduling dispatch and the centralized dispatch, and integrate the market-based power dispatch models and the cascading failure analysis to estimate the risk of cascading outages stemming from diverse dispatch solutions.

Synchrophasors allow fast, synchronized measurements of the power grid and have the potential to serve power system applications more e ectively. Synchrophasor data may allow analyzing subareas of the system without need for access to outer area information. This thesis focuses on implementing the area angle concept on subareas of networks for various power system tasks. First, we show the ability to decouple a subnetwork using only the area's synchrophasor measurements and superposition. Next we present a line outage detection algorithm within an area for both islanding and non-islanding cases. Finally, we discuss de ning area angles for meaningful analysis of a power system,particularly for areas in the WECC system.