A position estimation fault tolerant technology for switched reluctance motor (SRM) was proposed under the condition of the sensor fault and estimation error compensation based on the double current thresholds. In this method, the position index pulses were estimated by comparing the double current threshold value and the pulse current amplitude, and the speed and position could also be estimated by the position index pulses signals. Uing the independence of the SRM between the phase and the phase, the positions of the sensor fault phase were estimated using the electromagnetic information of the normal phase. The influence of the speed on position estimation error was obtained by simulation, and put forward the position error compensation measures. The experiment was carried out in a 12/8 structure prototype, the experimental results showed that the method could improve the fault tolerance of the sensorless sensor technology, and verify the correctness and feasibility of the algorithm.