挖掘机中的错相和缺相保护电路

Protecting Circuit of Phase-Change and Phase-Out in Excavator

本文从理论上分析了错相、缺相的判别原理，以及挖掘机上的实际应用电路，其线路简单、实用，同时给出了推广应用的方法。

The paper analyses a judging principle of phasechange and phase-out in theory, and a practical usage of the circuit in excavator, also gives a extended application of the circuit. The circuit is simple and useful.