Abstract: Dual three-phase synchronous reluctance motor (DTP-SynRM) has good fault tolerance performance due to its high degree of system freedom and strong redundancy. Since the rotor does not contain permanent magnets, there is no risk of high-temperature demagnetization. Open-circuit fault is one of the most common types of faults in dual three-phase synchronous reluctance motor systems. Aiming at the one-phase open-circuit fault of a DTP-SynRM with two sets of three-phase windings with independent neutral points, this paper establishes a vector space decoupling model to achieve complete decoupling of voltage, current, and flux equations. It is still regarded as a normal dual three-phase motor under the open-circuit fault condition, and the influence of the fault state on the current constraint and signal transmission of the motor is analyzed. It is also pointed out that under the open-circuit fault, the z₂ axis current and the β axis current are no longer independent, and the motor is downgraded from the fourth-order system during normal operation to the third-order system, and the inaccurate voltage signal transmission caused by the open-circuit fault will introduce the second harmonic current in the dq coordinate system and generate the second and fourth torque fluctuations. This paper proposes a fault-tolerant control strategy that considers both current constraint and signal transmission error, and the motor is in a three-loop operation state to compensate for the voltage signal transmission error, suppressing the torque fluctuation during the open circuit fault and reduce the current harmonics. An experimental platform is built for experimentation, which verifies the effectiveness and feasibility of the proposed fault- tolerant control strategy.