Single-phase power supply series-wound type overvoltage protector

The invention relates to a single-phase power supply series-wound type overvoltage protector. The overvoltage protector comprises a first voltage-limiting circuit and a second voltage-limiting circuit that are connected. The overvoltage protector has the two-level voltage-limiting circuits, so that surge voltage on a power transmission line can be reduced a lot; a positive temperature coefficient thermistor is added in the voltage-limiting circuits, so that electric current shock can be reduced in equipment starting up; and in addition, the protector has a low cost, a simple structure and wide adaptability.