Modelling and simulation of adaptive frequency relaying for distributed generation

Abstract

Modern utilities around the world have started the implementation of small scale local generation to support power supply. Introduction of distributed generation presents new challenges and opportunities for electrical engineers. One of the challenges is the change of network electrical characteristics. Network regulators have accommodated these changes in Grid Codes. One of the recent regulations is such that, the allowable system frequency variation changes according to mode of Microgrid operation. This poses a challenge to frequency protection engineers because currently frequency relays are non-adaptive, they operate based on fixed limits and thresholds for operation. An adaptive relay that can change its settings to suit the mode of Microgrid operation is advantageous. This paper presents an adaptive frequency relay model that can automatically change its settings to accommodate both modes of operation.