Asynchronous motors are widely used in various fields of production and life. Short-circuit between turns is a common problem of motor, which threatens the stable operation of modern industrial system, so it is of great significance to realize its condition monitoring and fault diagnosis. The traditional induction motor inter-turn short-circuit fault diagnosis is to determine the occurrence of fault by capturing the fault characteristic frequency in the current spectrum of the motor under constant load, but the load change will also produce modulation components in the current frequency domain, and even at some points the two are mostly the same, which may cause problem misjudgment. This paper analyzes the influence of short circuit fault and load fluctuation on current in detail, and obtains the characteristic frequency signal caused by them. Testing by taking a common variable load equipment centrifugal pump as an example, the load fluctuation characteristics of the centrifugal pump are obtained based on CFD numerical simulation and theoretical analysis. By using SVD singular value decomposition method to filter out the fundamental frequency and amplify the fault signal characteristics, it provides a basis for accurate monitoring of the inter-turn short circuit fault of induction motor under variable load.