Microgrid Fault Protection System

How to protect a microgrid from a fault?

Faults in the microgrid must lead to the distribution feeder isolation to eliminate the fault, reaching the smallest affected area [ 1 ]. The isolation speed of the system protection depends on the microgrid load characteristics. For this purpose, it requires the development of suitable electronic static switches.

Which type of fault is considered in microgrid protection schemes?

Another type of fault which is considered in microgrid protective schemes is the voltage sag. According to the plan drawn by for protection against this fault, the voltage phasor at the PCC ( V → s a g) during the sag period drops below its nominal value.

What is the framework of microgrid protection system?

The framework of microgrid protection system should be meticulous, reliable and must have high speed and low-cost operation. The process of microgrid protection must have following steps as shown in Fig. 4, which need to be followed starting from the occurrence of fault to the restoration of the normal operation of the system. Fig. 4.

Do microgrid protection systems work for different operating conditions?

A major challenge associated with the implementation of microgrids is to design a suitable protection system scheme for different operating conditions. To overcome this challenge, different approaches have been proposed in the literature. The protection systems applied at microgrids must work both in utility grid faults and microgrid faults.

What happens if a microgrid is faulty?

If fault occur in microgrid, then protection device quickly separates the faulty portion and rest of the system will remain in function. Some conditions of low voltages, voltage unbalances are strenuous to be identified and which may cause damage to the sensitive equipments.

How to protect a dc microgrid?

Different protection strategies for DC microgrid. 1. Calculate distance of the fault location using signal processing approach and impedance using Active Impedance Estimation method. To detect the fault location, transient part of current and voltage signal having high frequency is excerpted and send to the feeder.