A novel voltage regulator based on pulse width modulation（PWM） controlled AC chopper is proposed to solve the low voltage problem at the terminal of a distribution system， especially at the terminal of rural power network. Connected to the power supply line in series， the circuit starts up when the line voltage dropped and can maintain the load voltage within the acceptable range. The requirement on the capacity of this device is lowered since it only compensates for the insufficient part of the power supply line voltage. Based on AC chopper， the output voltage can be adjusted continuously within a wide range. The structure of this device is simple for its direct transfer of power from grid to load without the energy storage element. The topology and modulating method of the regulator are discussed in detail， and its application scope is studied. The accuracy and availability of this regulator are verified by both simulation and prototype results.