微电网保护问题与传统配电网保护有着极大的不同，典型表现在以下几个方面：a.微电网在并网运行和孤岛运行两种运行方式下，短路电流大小不同且差异很大。b.微电网中电源及相关负荷的接地方式对故障电流的大小影响也很大。c.加入分布式能源后，微电网的双向潮流特性对微电网保护的方向判别也有新的要求。d.发生故障时，微电网与配电网的不同隔离策略需要与微电网保护相结合，这也是微电网保护的关键。(The problem of microgrid protection is very different from that of traditional distribution network protection. Typical manifestations are as follows: a. The short-circuit current of microgrid varies greatly under the two operation modes of grid-connected operation and island operation. B. The grounding mode of power supply and related loads in microgrid also has a great influence on the magnitude of fault current. C. With the addition of distributed energy, the bidirectional power flow characteristics of microgrid also have new requirements for the direction discrimination of microgrid protection. D. When a fault occurs, different isolation strategies of microgrid and distribution network need to be combined with microgrid protection, which is also the key of microgrid protection.)