A voltage based protection for micro-grids containing power electronic converters

Protecting micro-grids containing micro-sources equipped with power electronics interfaces is a major challenge for engineers developing techniques to exploit renewable energy sources for electricity generation. Conventional techniques based on overcurrent protection have major limitations and new techniques have to be explored. The method described in this paper provides reliable and fast detection for different types of faults within the micro-grid. The micro-source output voltages are monitored and then transformed into dc quantities using the d-q reference frame. Any disturbance at the micro-source output due to a fault on the network will be reflected as disturbances in the d-q values. This disturbance is used to detect the fault and initiate the isolation the faulted section. Analysis and simulation results are presented for different types of faults within the microgrid