This paper analyzes the several basic modes characteristics of nozzle regulation

throttling regulation

bypass regulation

constant-pressure regulation and sliding pressure regulation of regulation of steam turbine

points out that there are many problems such as insufficient peak-shaving capacity

slow load response and the decrease of operation safety economy due to long-term deviation from the design conditions in the coal-fired thermal power units in active service.In order to realize the security

economy

flexibility

rapidity of participation in the deep peak shaving of power grid and solve the dilemma of large-scale grid-connected power of new energy with strong randomness and undulate

the optimal combination of adjustment mode is proposed

and the compound adjustment mode of（throttling） constant pressure-sliding pressure-（nozzle） constant pressure-bypass adjustment adopt is adopted.