SMART GRID PROTECTION

Abstract

Protection schemes for DC system is very challenging compared to conventional AC system. Power electronic devices are used in DC circuit breaker and converters. They have very less overloading capability. During fault, high current will flow through these devices and they will be switch off from system to protect from damage and whole DC bus to dc-energize. Under this condition fault location becomes very difficult. A fault protection method for a LVDC micro grid system is simulated in this thesis in order to solve above problems. The main aim of the protection technique is to detect fault and isolate faulty network from remaining system without de energizing the whole DC bus. To achieve this aim a ring bus is used for the main DC system. Main concern of proposed technique is to detect fault and isolate faulty segment quickly by calculating the fault location accurately by using pre fault and fault data. Similarly an AC microgrid is simulated with wind and solar integration. Fault distance is calculated using conventional or symmetrical fault method. The proposed methods have been verified using RTDS and MATLAB simulation.