Distributed control system(DCS) is a complex distributed control system

with various network security threats.These attack may target different levels of DCS system

such as network communication

data storage

application programs

etc.

making network risk security monitoring more complex.To this end

it designs a network risk security monitoring method for the DCS of coal-fired power plants.It designs a DCS for power plants using DCS technology

and designs a DCS process.Based on the DCS in power plants

a network risk monitoring model is constructed using improved Kalman filtering.The experimental results show that the security of the network environment under the application of research methods is improved

and the false alarm rate of monitoring is below 3%.