Emergency power source system for electric locomotive

The invention discloses an emergency power source system for an electric locomotive. The emergency power source system comprises an input/output disconnector, a control management unit, a lithium battery pack, a lithium battery charging and discharging management unit, a 3AC inverter power source unit, a DC110V inverter power source unit and a locomotive traction unit, wherein the control management unit is electrically connected with the other units respectively. With the emergency power source system of the invention adopted, power utilization requirements in normal life of a driver during a skylight open period can be satisfied, and locomotive braking emergency air compensation requirements during the skylight open period can be also satisfied, and the unit operation of the locomotive can be driven to a distance larger than or equal to 1000m, and a self-help electric locomotive movement function can be realized, and the safety of maintenance personnel can be greatly improved, and locomotive movement operation convenience can be improved for the maintenance personnel, and investment on overhead line system disconnecting equipment can be deceased, and maintenance efficiency can be improved.