Protection of Electric-Distribution Systems with Dispersed Storage and Generation (DSG) Devices

摘要

The DSG protection problem areas are identified. Several simulations of protection problems are presented to show the nature of the various types of problems encountered. These simulations considered phenomena as resonance, islanding, fluctuating generation, and faults. An evaluation is made of the adequacy of present protection schemes with respect to the simulation results. Present schemes are found to be adequate in most areas except for protection against islanding. Guidelines are given to help utility distribution engineers design proper protection schemes. A special protection package for small- and medium-sized DSG installations is recommended; this would simplify interconnection of DSG with the utility system. Specifications of the package are given. The feasibilty of designing the package around a microprocessor-based relay is investigated. It is found that technical barriers have almost been overcome, and it should be practical to produce such a device soon. (ERA citation 08:055726)