Abstract: Several layout schemes of gas turbine combined cycle units were introduced. The type of uniaxial combined cycle unit was researched and compared with other types emphatically. Then the obtained conclusion is that for many paralleled sets of Fclass uniaxial combined cycle units, must implement the unitmode compact layout, the unitmode construction, the unitmode operation and overhaul, and must be convenient for extension construction.

Key words: combined cycle unit, unit type, layout scheme, compare, research