Partial discharge inception voltage (PDIV) under repetitive pulse voltage is an important parameter to evaluate the insulation performance of low-voltage random-wound inverter-fed motors. Different from the traditional sinusoidal voltage, the rise time and polarity of the impulse are critical parameters to be considered when PDIV test is carried out on the turn to turn insulation of the winding for inverter-fed motor at repetitive impulsive voltages. In this paper, the influence of repetitive impulsive voltage rise time on the PDIV and energy distribution features of turn to turn insulation for inverter-fed motors with three specification were investigated at repetitive impulse voltages with different impulse rise times (50 ns, 75 ns, 100 ns, and 200 ns), and the mechanism of variation of PDIV with different rise times was discussed. The results show that with the decrease of rise time, the PDIV of three motors decreases, and the maximum decline rate reaches 28.1%. The influence of repetitive pulse polarity on the PDIV test results of low-voltage random-wound inverter-fed motor is limited, indicating that both positive and negative can objectively reflect the PDIV performance of motor. With the increase of impulse rise time, the discharge energy in frequency domain moves from high frequency to low frequency. The research results are expected to provide reference for PDIV test of low voltage inverter-fed motor insulation and the revision of related standards.