Three-speed electric vehicles

The invention provides a three-speed electric vehicle. The three-speed electric vehicle comprises a motor, a controller and a relay; a winding of the motor comprises a high-speed gear, a medium-speed gear and a low-speed gear; the relay comprises two individual relays which are integrated in a housing; one relay is equipped with a common terminal, while the other one is not equipped with a common terminal; a normally-closed contact of the previous relay is connected with a dynamic contact of the other relay; a signal switching conditioning signal of the controller comprises two driving circuits which are respectively driven by two I/O ports of a single-chip microcomputer to control the connection or disconnection of coils of the relays A and B; three-phase output ports of a motor driving circuit are respectively connected with a low-speed gear, medium-speed gear or high-speed gear winding of the motor by switching the relay A and B; a motor hall sensor is connected with the single-chip microcomputer through a hall signal conditioning circuit; relay conditioning circuits are connected with the control ends of the relays A and B. According to the three-speed electric vehicle, the speed of the electric vehicle is controlled through the three-speed motor, the three-speed controller and the three-gear relays, and therefore, the rotating speed difference of the three gears is relatively small, and the switching effect is relatively smooth and comfortable.