The need for investigation of distribution system phenomena and engineering considerations has been increasing for a long time. Although the distribution system is a very dynamic portion of the utility system, accounting for a substantial share of utility's capital and operating expense, it has not generally received the same degree of research effort as the generation and transmission portions of the system. Greater understanding is needed of the present-day system and equipment application concerns as systems evolve, reliability considerations are heightened, and new and more complex loads are added to today's distributions systems.

Many of these distribution system research and testing needs are now being met by a consortium of utilities and utility organizations. This consortium, known as the Distribution Systems Testing, Application, and Research (DSTAR) group, has been sponsoring investigations of practical distribution issues since 1986.

The formation of DSTAR is, to a great extent, due to the initiative of Northeast Utilities (NU). This utility appreciated the need for a distribution-focused research and testing program and sought to fulfill these needs within a consistent framework and with a means for equitably funding the projects. In the early 1980's, NU conducted a search and evaluation of various test and research capabilities. NU was seeking impulse and short circuit generation capability, measurement, and proximity to existing distribution facilities. Their evaluation favored GE's High Voltage Laboratory in Pittsfield, Massachusetts and GE's Skeats High Power Lab in Philadelphia. These facilities plus the extensive distribution system and equipment application expertise provided by GE's Power System Engineering Department led to the close relationship which continues today between the DSTAR consortium and GE.

Northeast Utilities was joined in the initial project by five other utilities and one utility organization, with service territories concentrated in the northeastern portion of the country. DSTAR has since grown to its present size as other utilities have seen the value in their participation, and now encompasses utilities throughout the United States. The research activities have broadened from the original scope of underground cable surge protection to a diverse range of topics related to practical distribution system engineering and operations, including distribution transformer overvoltage phenomena and protection, overcurrent protection, transformer sizing and selection, and development of software tools.