Abstract: A novel dual-stator brushless doubly-fed generator（DS-BDFG） coupled with inner and outer back-to-back cage-barrier rotor and an improved speed sensorless direct power control（DPC） are presented. The inner and outer in-phase power winding and control winding are all connected in series, respectively, the super-twisting sliding mode（STSM） and space vector pulse width modulation（SVPWM） control technologies are used to drive and control the power devices of the machine side converter（MSC） of the control winding with an fixed switching frequency. The model reference adaptive system（MRAS） and Popov hyperstability theorem are applied to design the generator speed observer and used to replace the traditional electromechanical speed/position sensor which is prone to failure. With the simulation results of the 12/8-pole 50 kW prototype control system, the correctness and effectiveness of the proposed sensorless super-twisting sliding mode direct power control（STSM-DPC） strategy are verified in detail.