In this system, a 160KW hoist motor is driven by a D32 200KW inverter, and one hoist simultaneously drives the left and right two trolleys to go up and down each other, that is, one of the trolleys feeds upward, and the other trolley Descend for an empty car. The inverter bus voltage may be pumped up in occasions such as deceleration braking and top unloading, and the external braking unit and braking resistor are used to achieve rapid braking and stopping.