The potential of distributed generation to provide ancillary services

TLDR

Growing concerns about power quality and availability, coupled with deregulation and service unbundling, are driving increased deployment of distributed generation and creating a market for ancillary services. This paper examines how distributed generation can supply ancillary services such as spinning reserve, voltage support, reactive power, and power‑quality functions, and discusses the design implications for power‑converter interfaces. The authors review distributed‑generation types, power‑electronic interfaces, and configurations that enable ancillary services, including voltage‑sag compensation and harmonic filtering, and analyze design considerations for converters. Power‑electronic interfaces provide flexible features that enable distributed generation to deliver these ancillary services.

Abstract

The growing concerns regarding electric power quality and availability have led to the installation of more and more distributed generation. In parallel and in the context of an accelerating trend towards deregulation of the electric industry, the unbundling of services, many grouped under ancillary services, should create a market for some of these services. This paper discusses the potential of distributed generation (DG) to provide some of these services. In particular, DG can serve locally as the equivalent of a spinning reserve and voltage support of the AC bus. The main types of distributed generation with emphasis on the power electronic interface and the configurations appropriate to provide ancillary services are reviewed. The flexibility and features provided by the power electronic interface are illustrated. In addition to control of the real power, other functions can be incorporated into the design of the interface to provide services, such as reactive power, and resources associated with power quality. These include voltage sag compensation and harmonic filtering. The implications on the design of the power converter interface are discussed.