Anti-interference electricity type device with autonomous matching mode

The invention relates to a voltage sag prevention device with an autonomous matching mode. The voltage sag prevention device comprises an alternating current LN power supply, an AC/DC rectifying circuit, an operation controller circuit, a sampling circuit, a driving circuit, a six-way electronic switch and an output port, the interference electricity prevention device is further provided with an autonomous matching mode, and when the contactor is in a closed state, impedance matching calculation, current matching calculation, voltage matching calculation, autonomous identification verification and normal operation matching are automatically and sequentially executed. The corresponding switches of the six electronic switches are controlled to be switched off and switched on according to the positive half cycle or the negative half cycle of the voltage of the interference electricity, and the output voltage of the AC/DC rectifying circuit is calculated and controlled according to the K value which is automatica