IEEE Approved Draft Recommended Practice for Fault Diagnosis and Protection in Smart Distribution System

The fault diagnosis and protection schemes and application cases for smart distribution systems from ac 6 kV to 20 kV are provided by this recommended practice, covering security requirements, architectures, and configuration, as well as basic functions and technical indexes of software systems and hardware terminals and requirements of information exchange. Schemes provided in this document are adaptable to various operation modes, control patterns, equipment conditions, and reliability requirements of distribution systems. This recommended practice is mainly based on engineering practices in the voltage range of 6 kV to 20 kV. The proposed fault location, isolation, and service restoration (FLISR) schemes can also be used in the voltage range of 2.4 kV to 38 kV as specified in ANSI C84.1 after an evaluation of communication conditions and cost analysis. Phase (three-phase and phase-to-phase) faults, ground (three-phase-to-ground, two-phase-to-ground, and single-phase-to-ground) faults and conductor-broken faults are covered by the fault types. Changes and needs brought by the connection of distributed generators are considered, and schemes empowered by information and communication technologies are also introduced.