Active islanding detection for synchronous generators using speed disturbance injection technique

Dispersed generation in the form of renewable energy is being used widely nowadays. Besides the immense benefits of using DGs, they can also be used in the islanded mode. Islanding, though not utilized by many utilities around the world due to safety and lack understanding of the technology, can ensure that the load receives continues supply. In order to detect the islanding phenomenon, various islanding detection methods have been developed. Islanding detection methods are classified into communication-based methods and Local Measurement Detection Methods (LMDMs) where LMDM can be further categorized into the active and passive methods. Utilities tend to use the LMDMs since they are economical and simple to implement. However, LMDMs have a None-Detection Zone (NDZ) at equilibrium point of load and generation during islanding. In this paper, a test system has been developed in EMTDC/PSCAD software in order to investigate an active LMDM performance in distribution system. Results show that the proposed active detection method can be used as an index for islanding detection in the presence of the various load condition.