The reason for speed jump fault of turbine magneto resistance speed measurement is complex and the treatment is very difficult. This paper analyzes the general characteristics of the speed detection circuit in the form of a case

and makes an in-depth study on the generation mechanism of the jump of the magneto resistive speed measurement speed signal. The results show that

most of the reasons for the jump are the poor matching between the speed measurement gear and the magneto resistive sensor. Under the action of the shaft vibration of the steam turbine

the speed signal generates zero crossing harmonic. When the amplitude of the zero crossing harmonic is greater than the threshold of the detection circuit

the speed jumps

and the magnitude of the speed jump is related to the number of zero crossing harmonics exceeding the threshold. A new method of correcting speed jump with capacitance is proposed

and its feasibility is theoretically analyzed. Moreover

the key points of the implementation process of this method are explained.