A rotor includes a rotor iron core, a rotor shaft, and a fastening plate. The rotor iron core includes a first and a second end, and extends along an axial direction. The first fastening plate is fastened to at least the first or second end, and includes a through hole and a first runner. An inlet of the first runner communicates with the through hole. An outlet of the first runner is on a surface of a side of the fastening plate. The rotor shaft includes a second runner and a third runner in the rotor shaft. An inlet of the second runner is at one end of the at least one end of the rotor shaft. An outlet of the second runner communicates with an inlet of the third runner. An outlet of the third runner communicates with the inlet of the first runner.