MICROGRID ADAPTIVE OVERCURRENT PROTECTION METHOD

摘要

A microgrid adaptive overcurrent protection method, comprising the following steps: 1. configuring a central protection unit in a microgrid structure, and configuring a local protection unit at each breaker, communication being conducted through optical fibers between local protection units and between the local protection units and the central protection unit; 2. configuring adaptive current protection at each local protection unit; 3. the central protection unit acquires in real time system operation information uploaded by the local protection units, and determines microgrid operation mode, a fault type and a fault point location; 4. in grid-connected operation mode, the local protection units conduct real-time sampling on the voltage of a bus and the current of a feeder line, and determine system impedance according to the sampling value; and in an islanding operation mode, the local protection units calculate the setting value for current quick-break according to the fault type; 5. the central protection unit compares a current value actually measured with the setting value, and determines fault separation and power supply restoration. The method facilitates the adaptive overcurrent protection of the microgrid.