The invention discloses a dynamic trend control method based on a wide-scope controllable transformer comprising bidirectional power tubes. By use of a rapidly conducted and broken electric electronic switch, conduction and breaking of a tap joint at the output side (secondary side) of the wide-scope controllable transformer are controlled, another two phases of windings are connected in series with the side of each phase of the tap joint of the wide-scope controllable transformer, at the same time, the four bidirectional power tubes are additionally arranged for changing the conduction directions of intersected-phase windings, the phase and the amplitude of output voltages of the controllable transformer can be changed in a maximum scope, adjustment of active power and reactive power is realized, since conduction of the tap joint of the wide-scope controllable transformer is controlled, the dynamic trend of a power network can be adjusted and controlled, and the method has the advantages of low cost and high control reliability of the dynamic trend.