The paper analyzes the driving system of belt conveyor, expatiates the application of voltage-to-frequency converter (VFC) for belt conveyor driving in the field of middle and high voltage. The three-electrical-level inverter using high-voltage IGBT based on neutral-point clamping principle as well as the driving system of induction motor adopting the strategy of rotor magnetic field vector control are discussed. The application of HV-IGBT shows good applied prospects for the strategy of vector control or d...