Emergency electric power source system for pitch system

The invention discloses an emergency electric power source system for a pitch system. The emergency electric power source system comprises a charging module, an ultracapacitor module, a dynamic equilibrium module and a warning module, wherein the charging module is connected with the ultracapacitor module; the ultracapacitor module is charged by the charging module; the ultracapacitor module is composed of a plurality of ultracapacitor single bodies; a state monitor module is used for monitoring working voltage and working temperature of corresponding ultracapacitor single bodies; the voltage values of the ultracapacitor single bodies are monitored by the dynamic equilibrium module through the state monitor module, so that the ultracapacitor module is controlled to discharge current in a dynamic manner. The emergency electric power source system is special for the pitch system in a wind turbine generator, when the main system of the wind turbine generator is powered off, the emergency electric power source system can drive the pitch system to accomplish pitch smoothening.