Main rack of wind turbine generator

The invention discloses a main rack of a wind turbine generator. The main rack comprises a bottom plate, an outer web plate, an inner web plate, cover plates and a side plate, wherein a conical through hole is formed in the middle of the bottom plate, two mounting plates are oppositely arranged on the two sides of the bottom plate, and a plurality of mounting holes used for being connected with a yaw mechanism are formed in each mounting plate; the outer web plate comprises a U-shaped web plate and a curved-surface web plate which are arranged on the bottom plate, and two groups of cover plates are arranged at the top of the outer web plate; each group of cover plates comprises a first cover plate, a second cover plate and a supporting cover plate and is used for mounting a bearing seat of the wind turbine generator; the inner web plate is arranged between the two groups of cover plates and comprises a first inner web plate, a second inner web plate, a third inner web plate and a fourth inner web plate; and t