Self-adaptive optical path compensation method of double-path plug-and-play quantum key distribution system

The invention provides a self-adaptive optical path compensation method of a double-channel plug-and-play quantum key distribution system, and belongs to the technical field of quantum communication,which can solve the problem that an optical device in the existing double-channel plug-and-play quantum key distribution system is easily influenced by an external environment so that the system cannot efficiently and stably operate for a long time. Accurate control and compensation are carried out on control clock delay of a phase modulator at an Alice end, a phase modulator at a Bob end and single-photon detectors SPD0 and SPD1 for detecting photons at the Alice end;; and real-time compensation is carried out during starting and in the operation process respectively, so that the quantum keydistribution system can keep the working parameters of the core optical device in a better state before starting and operating each time, and the system can be kept in an efficient working state for along time so as to keep ef