High-voltage variable-frequency soft start system

A high-voltage variable-frequency soft start system comprises a high-voltage frequency conversion device and an electric motor, wherein a variable-frequency soft starter is arranged in the high-voltage frequency conversion device; the input terminal of the variable-frequency soft starter is connected with a variable-frequency input switch; the other end of the variable-frequency input switch is connected with a high-voltage input switch; the other end of the high-voltage input switch is connected with a power frequency grid; the output terminal of the variable-frequency soft starter is connected with a variable-frequency output switch; the other end of the variable-frequency output switch is connected with the electric motor; and a power frequency switch is arranged between the variable-frequency input switch and the variable-frequency output switch. The high-voltage variable-frequency soft start system avoids secondary current impact and circumferential flow, and has a better phase-locked control effect and lower control demand.