The cause of the slow speed motor load runtime

The cause of the slow speed motor load runtime electric vehicle motor 1),power supply voltage is too low 2),squirrel cage rotor broken bar 3),a faulty coil or coil set point 4),coil,or there are meet the coil assembly 5),the reverse phase winding 6),overload 7),wound rotor type electricalmotor1.blogspot.com a break 8),wound rotor type motor starting rheostat poor contact 9),brush and slip ring poor 8500w gasoline generator contact.