Abstract The digital monitoring on auxiliary power system is a key point of the power plants automation. Operation modes, information architecture, function and problems of electrical control and management system (ECMS) in power plant are discussed in this paper. The ECMS with 2-layer and 3-layer composite construction using IEC 61850 and DP protocol was firstly implemented in ShenFu HongShan Power (2×1000MW). The operation risks, preventive measures and solutions for application problems are discussed.