To develop compatibility levels and to deepen the understanding of system performance, data on power quality are being collected by various agencies from around the world. Some of these organizations are Electrical Power Research Institute (EPRI), Canadian Electrical Association, National Power Laboratories (Necedah, Wisconsin), Norwegian Electric Power Research Institute, International Union of Producers and Distributors of Electrical Energy (UNIPEDE), Electricite de France, Northeast Utilities Service (Berlin, Connecticut), East Midlands Electricity (EME, Nottingham, England), and Consolidated Edison Company of New York, Inc.

Because of reasons of cost, power quality monitoring is still in its infancy. However, as a result of deregulation in the utility industry in many countries, they will be forced to compete for customers.

One of the ways in which they can achieve this is by monitoring power quality and showing the customers that their power supply reliability is better than that of their competitors. Hence, utilities on their own are likely to undertake more monitoring of the feeders supplying their major customers. The data required to monitor power quality are usually voluminous.

Hence, software must be used to automatically characterize measured events and store the results in a well-defined database. It will be economical to integrate the data collected from power quality and in plant monitoring with electric power instrumentation, site descriptions, and event information. For details of a power quality database management and analysis system called PQView, developed by Electrotek Concepts, Inc. (Knoxville, Tennessee).

Over the last several years, the EPRI and one of its contractors (Electrotek Concepts, Inc.) have been developing a vendor-independent interchange format for power quality-related information. For the details of this Power Quality Data Interchange Format (PQDIF), PQView, and PQWeb systems.

In 1996, EPRI and Electrotek placed PQDIF in the public domain to facilitate the interchange of power quality data between interested parties. EPRI and Electrotek have also offered the format, sample source code, and documentation to the IEEE 1159.3 task force as a possible initial format to meet that group’s requirements.

In 1991, the Power System Relaying Committee of the IEEE Power Engineering Society developed the standard C37.111.39 The main purpose of this standard was to define a common format for the data files and exchange medium needed for the interchange of various types of fault, test, or simulation data.

Among others, the standard defines as sources of data the following: digital fault recorders, analog tape recorders, digital protective relays, transient simulation programs, and analog simulators. For the details of indices for assessing the harmonic distortion of power quality, D. Daniel Sabin et al.

A power quality database can provide a basis for developing equipment compatibility specifications and guidelines for future equipment enhancements. In addition, a database of the causes for recorded disturbances can be used to make system improvements.

By ensuring equipment compatibility, safety hazards resulting from equipment misoperation or failure can be avoided. Performance indices that measure system reliability in terms of voltage outages are defined in a document (Reference 31) prepared by the EPRI, Palo Alto, California.

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