Because of the reliability requirement for the motor driving system in practical application, and based on analysis of the working principle of a fault-tolerant inverter, the direct torque control (DTC) for brushless direct current motor (BLDCM) fed by four-switch three-phases inverter (FSTPI) when the inverter faults is widely studied. According to the characteristics of (BLDCM), the voltage space vector for BLDCM-DTC fed by FSTPI is redefined due to the dissymmetric voltage space vector of TPFSI. To reduce the number of power device switching, the implementation method of four-switch SVPWM with seven-segment scheme was presented. Therefore, the system model is established as a result of the detailed analysis of voltage space vector and the control principle of the BLDCM-DTC without flux linkage observation fed by FSTPI. The validity and effectiveness of the proposed scheme have been verified through the simulation and experimental results.