A rectification device comprising: a rectification circuit forming a quadrilateral bridge type circuit, the rectification circuit including switch elements (Qa, Qb), through which a feedback current flows to an AC power source and rectification elements (Da, Db); an input voltage detector arranged to detect an input voltage from said AC power source; an input current detector arranged to detect an input current from said AC power source; and a control circuit arranged to control the switch elements (Qa, Qb) so that the rectification circuit outputs a predetermined DC voltage by generating a synchronized sine wave synchronized with the input voltage, generating an input current target value based on the synchronized sine wave, and controlling, in each half-cycle of the synchronized sine wave, a respective first switch element of the switch elements (Qa, Qb) in an on-keeping mode so as to allow the feedback current to flow through the first switch element to the AC power source while a respective second switch element of the switch elements (Qa, Qb) is controlled by the control circuit in a switching mode by modulating pulse widths of pulse signals according to a difference between the input current and the input current target value, characterized in that the control circuit is arranged to determine when short-circuiting in the AC power source caused by a switching state of the switch elements (Qa, Qb) needs to be prevented, by determining when one of a polarity of the input voltage, a polarity of the input current, and a polarity of the synchronized sine wave differs from the other polarities, and when said determination that the short-circuiting needs to be prevented is made, said control circuit is further arranged to execute in each half-cycle of the synchronized sine wave one of: controlling the switch elements (Qa, Qb) in the switching mode so as to perform switching operation at the same ON/OFF ratio; turning off one switch element of the switch elements (Qa or Qb), which switch element would cause the short-circuit in the AC power source if controlled by the control circuit to operate in the on-keeping mode; and turning off the switch elements (Qa, Qb). a rectification circuit forming a quadrilateral bridge type circuit, the rectification circuit including switch elements (Qa, Qb), through which a feedback current flows to an AC power source and rectification elements (Da, Db); an input voltage detector arranged to detect an input voltage from said AC power source; an input current detector arranged to detect an input current from said AC power source; and a control circuit arranged to control the switch elements (Qa, Qb) so that the rectification circuit outputs a predetermined DC voltage by generating a synchronized sine wave synchronized with the input voltage, generating an input current target value based on the synchronized sine wave, and controlling, in each half-cycle of the synchronized sine wave, a respective first switch element of the switch elements (Qa, Qb) in an on-keeping mode so as to allow the feedback current to flow through the first switch element to the AC power source while a respective second switch element of the switch elements (Qa, Qb) is controlled by the control circuit in a switching mode by modulating pulse widths of pulse signals according to a difference between the input current and the input current target value, characterized in that the control circuit is arranged to determine when short-circuiting in the AC power source caused by a switching state of the switch elements (Qa, Qb) needs to be prevented, by determining when one of a polarity of the input voltage, a polarity of the input current, and a polarity of the synchronized sine wave differs from the other polarities, and when said determination that the short-circuiting needs to be prevented is made, said control circuit is further arranged to execute in each half-cycle of the synchronized sine wave one of: controlling the switch elements (Qa, Qb) in the switching mode so as to perform switching operation at the same ON/OFF ratio; turning off one switch element of the switch elements (Qa or Qb), which switch element would cause the short-circuit in the AC power source if controlled by the control circuit to operate in the on-keeping mode; and turning off the switch elements (Qa, Qb). controlling the switch elements (Qa, Qb) in the switching mode so as to perform switching operation at the same ON/OFF ratio; turning off one switch element of the switch elements (Qa or Qb), which switch element would cause the short-circuit in the AC power source if controlled by the control circuit to operate in the on-keeping mode; and turning off the switch elements (Qa, Qb).