Quantitative Calculation of Motor End Overvoltage and Analysis of Over Double Overvoltage Under High Frequency.

Abstract:
This essay conducts theoretical analysis and simulation verification on the mechanism and influencing factors of motor terminal overvoltage. Firstly, based on the theory of wave reflection, analyze the reflection process of voltage waves in transmission cables and the mechanism of overvoltage generation at the motor end. Then, based on the theory of distributed parameter transmission lines, the Thevenin equivalent circuit of the transmission cable is derived, and a theoretical model of the motor terminal voltage is obtained. Finally, based on the theoretical model of motor terminal voltage, the effects of motor terminal reflection coefficient, cable length, voltage rise time, and cable distribution parameters on motor terminal voltage are analyzed, with a focus on the problem of over double overvoltage caused by high switching frequency. Simulink simulation model of motor terminal voltage is established to verify the above analysis.