AC/DC converter with sinusoidal input current and a single conversion stage

Stringent power supply quality standards have been introduced which limit harmonic distortion in power systems. It is general practice to eliminate the harmonics and to design switch mode power converters in such a way as to draw a pure sinewave current from the supply installation with power factor close to one. The most typical way to meet this requirement is to design a converter with two conversion stages for wave shaping of the input current and generation of a smooth DC voltage. An AC/DC power converter where both functions are performed by means of a single switching power transistor and a single magnetic component, reducing the complexity of the circuit and saving the cost of components and space, is presented. A simpler circuit also enhances the reliability of the device. Voltage and current relationships in the converter connection are analyzed. The advantages and disadvantages of the connection are given