In Australia and many other countries, distribution network service providers (DNSPs) have an obligation to their customers to provide electrical power that is reliable and of high quality. Failure to do so may have significant implications ranging from financial penalties theoretically through to the loss of a license to distribute electricity. In order to ensure the reliability and quality of supply are met, DNSPs engage in monitoring and reporting practice. This paper provides an overview of a large long-running power-quality monitoring project that has involved most of Australia's DNSPs at one time or another. This paper describes the challenges associated with conducting the project as well as some of the important outcomes and lessons learned. A number of novel reporting techniques that have been developed as part of the monitoring project are also presented. A discussion about large-volume data management, and issues related to reporting requirements in future distribution networks is included.Abstract -In Australia and many other countries, distribution Network Service Providers (DNSPs) have an obligation to their customers to provide electrical power that is reliable and of high quality. Failure to do so may have significant implications ranging from financial penalties theoretically through to the loss of a license to distribute electricity. In order to ensure the reliability and quality of supply are met, DNSPs engage in monitoring and reporting practice.This paper provides an overview of a large long-running power quality monitoring project that has involved most of Australia's DNSPs at one time or another. The paper described the challenges associated with conducting the project as well as some of the important outcomes and lessons learned. A number of novel reporting techniques that have been developed as part of the monitoring project are also presented. A discussion about large-volume data management, and issues related to reporting requirements in future distribution networks is included.

Abstractiscrete or event type power quality (PQ) disturbances mainly include voltage sags, swells, and the transients. An extensive literature survey suggests that there is no generally accepted method for characterization of these disturbances and suitable limits are not yet found in any international standard. One of the reasons for the lack of characterization methods is the difficulty of defining suitable site indices for each discrete disturbance type. In this paper existing characterization methods are reviewed and discussed. A new generalized approach is then given to show a better way of characterizing voltage sags, swells and transients. This is followed by a proposed new method of defining MV/LV distribution discrete disturbance limits for general utility networks and their suitability is shown by an examination of some Australian sites.

The rollout of advanced metering infrastructure, advanced distribution automation schemes, and integration of generation into distribution networks, along with a raising of awareness of power quality (PQ), means that there is an increase in the availability of power system monitoring data. In particular, the data for harmonics, whether it is voltage or current harmonics, is now available from a large number of sites and from a diverse range of PQ instruments. The traditional analysis and reporting of power quality examines harmonic orders to the 50th. This means that the harmonic data available for analysis are significantly larger than, for example, steady-state voltage variations where only a few parameters are examined (e.g., the voltage on each phase). Higher frequency components, sometimes called highfrequency harmonics, in the 10-250 kHz range arising primarily due to power-electronic interfaced generation are also becoming significant. Given the vast amount of harmonic data that will be captured through grid instrumentation, a significant challenge lies in developing methods of analysis and reporting that reduces the data to a form that is easily understood and clearly identifies issues but does not omit important details. This paper introduces a number of novel methods of analysis and reporting which can be used to reduce vast amounts of harmonic data for individual harmonic orders down to a small number of indices or graphical representations which can be used to describe harmonic behavior at an individual site as well as at many sites across an electricity network. The methods presented can be used to rank site performance in order for mitigation strategies. The application of each method described is investigated using real-world data.

Power quality indices are being developed that attempt to quantify certain aspects of service quality. There has been considerable amount of work on the characterization of individual types of power quality disturbances and corresponding indices. However, there does not exist in the literature a standard approach that allows one to quantify the overall power quality. This paper proposes a unified power quality index (UPQI) as a useful tool for ranking sites as to their overall power quality. Absfrod-Power quality indices are being developed that attempt to quantify certain aspects of senire qualih. There has been considerable amount of work on the characterization of individual types of power qualie disturbances and correspanding indices. However, there does not exist in the literature a standard approach that allows one to quantify the overall power quality. This paper propares B Unified Power Quality Index (WQI) as a useful tool for ranking sites as to their overall power quality. Disciplines Physical Sciences and Mathematics

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Absfract-A pn-diode micro-model representing forward and reverse recovery phenomena is presented for power electronic simulation, especially using SPICEZ. The model is proposed to compensate the incompleteness of the diode model in current circuit simulation packages. In the forward recovery submodel, the diode bulk resistance modulation and its forward current dependence are included. In the reverse recovery submodel, the charge control equation for excess storage carriers is employed to simulate the detailed behavior. A procedure is described for extracting the model's physical parameters from data sheet information. The model is verified by a comparison of experimental results for several different tests with SPICE simulations. A discussion is given of extending the applicability of the micro-model to the simulation of p-i-n diode behavior.

This paper describes the performance of an experimental 5kW nine-phase synchronous reluctance motor (Syncrel) drive. Increasing the number of phases of the Syncrel above three allows the stator MMF's to be shaped, producing significantly greater torque / RMS ampere in the same volume machine. Generalized d-q voltage and torque equations are derived for the nine-phase Syncrel. These demonstrate that harmonic direct and quadrature components of current contribute to torque production in the machine and can be controlled by applying appropriate stator voltages. A fieldoriented controller is described and implemented using a TMS320C32 digital signal processor board. The controller designates portions of the stator winding as supplying either direct or quadrature excitation. A simple inverter switching strategy is used to control the phase currents to their reference values. Experimental current regulation, speed response and torque measurements are presented from the drive. These results validate the system model and demonstrate the drive capability. 2041 0-7803-7116-X/01/$10.00 (C) 2001 IEEE

Abstract-The Australian Long Term National Power Quality Survey (LTNPQS) is a large multi-utility power quality survey which has now been in operation for 8 years. This paper details the latest innovative developments in the reporting and analysis procedures developed for the LTNPQS. The paper also highlights the key power quality issues affecting Australian electricity networks at the present time. These include high voltage levels at LV sites and difficulties in measurement of voltage unbalance. The longevity of the survey has allowed better understanding of disturbance trend levels. Interesting results include an apparent reduction in harmonic levels in the past couple of years and no definite trend in sag levels even with 7 years worth of data.Some of the challenges involved in conducting a survey of this type are explored and indications as to solutions presented. With the implementation of smart grid concepts it is likely that the number of sites with instrumentation capable of supplying data to the survey will increase exponentially. This presents a new set of challenges and the survey must adapt to these. Future directions taken in response include the implementation of web-based reporting systems which will provide more flexibility for participants.