A rectifier apparatus having a configuration in which a single-phase AC power source is short-circuited and opened via a reactor by chopping a semiconductor switch to supply a current from an AC side to a DC side via the reactor, the rectifier apparatus comprising: means for forming a target current waveform of same frequency as that of an AC voltage waveform; means for detecting a current on the AC side or a current on the DC side; means for detecting a DC voltage; means for controlling chopping of the semiconductor switch by adjustment so that the target current waveform and the detected current waveform become same shape as each other; means (206, 207) for adjusting an amplitude of the target current waveform so that the DC voltage becomes a desired voltage; and means for detecting a phase of the AC voltage; characterized in that the rectifier apparatus further comprises: means to shift the semiconductor switch to a chopping start state in a phase interval during which the AC voltage is lower than the DC voltage and the target current waveform is not zero and to shift the semiconductor switch to a chopping stop state in a phase interval during which the AC voltage is higher than the DC voltage; and means for judging a phase (θ ON) when the semiconductor switch starts chopping, based on a detected phase of the AC voltage and a current command adjusted for generating ON/OFF information of chopping of the semiconductor switch; and means (204, 205) for adjusting the DC voltage (Vdc) so that the phase (θ ON) when the semiconductor switch starts chopping becomes a desired phase (θ ON *). means for forming a target current waveform of same frequency as that of an AC voltage waveform; means for detecting a current on the AC side or a current on the DC side; means for detecting a DC voltage; means for controlling chopping of the semiconductor switch by adjustment so that the target current waveform and the detected current waveform become same shape as each other; means (206, 207) for adjusting an amplitude of the target current waveform so that the DC voltage becomes a desired voltage; and means for detecting a phase of the AC voltage; characterized in that the rectifier apparatus further comprises: means to shift the semiconductor switch to a chopping start state in a phase interval during which the AC voltage is lower than the DC voltage and the target current waveform is not zero and to shift the semiconductor switch to a chopping stop state in a phase interval during which the AC voltage is higher than the DC voltage; and means for judging a phase (θ ON) when the semiconductor switch starts chopping, based on a detected phase of the AC voltage and a current command adjusted for generating ON/OFF information of chopping of the semiconductor switch; and means (204, 205) for adjusting the DC voltage (Vdc) so that the phase (θ ON) when the semiconductor switch starts chopping becomes a desired phase (θ ON *). means to shift the semiconductor switch to a chopping start state in a phase interval during which the AC voltage is lower than the DC voltage and the target current waveform is not zero and to shift the semiconductor switch to a chopping stop state in a phase interval during which the AC voltage is higher than the DC voltage; and means for judging a phase (θ ON) when the semiconductor switch starts chopping, based on a detected phase of the AC voltage and a current command adjusted for generating ON/OFF information of chopping of the semiconductor switch; and means (204, 205) for adjusting the DC voltage (Vdc) so that the phase (θ ON) when the semiconductor switch starts chopping becomes a desired phase (θ ON *).