A power converter providing power to a compressor in an air conditioning apparatus, the power converter comprising: a rectifier configured to rectify an input alternate current from an AC power source; a power factor corrector including a reactor (L25a, L25b, L25c) and a switching device (Q25a, Q25b, Q25c) which switches between accumulation and discharge of energy, based on an input voltage output from the rectifier, in and out of the reactor (L25a, L25b, L25c), and configured to be capable of performing a power factor correction operation by boosting the input voltage; a power converter connected to an output of the power factor corrector, and configured to generate output AC power (SU, SV, SW); and a controller configured to control the power factor correction operation by the power factor corrector, characterized in that the power factor corrector includes a smoothing capacitor provided close to an output of the reactor (L25a, L25b, L25c), and connected in parallel to the switching device (Q25a, Q25b, Q25c), and the controller is configured to: turn the switching device (Q25a, Q25b, Q25c) off so that the power factor correction operation stops, if an instantaneous voltage drop or an instantaneous power failure occurs in the AC power source while the power factor corrector is performing the power factor correction operation; leave the compressor driving without rest, if the instantaneous voltage drop or the instantaneous power failure occurs while the compressor is driving; leave the power factor correction operation stopped when the AC power source recovers; and permit the power factor corrector to perform the power factor correction operation, if the compressor continues driving from recovery of the AC power source through a predetermined time period; wherein the predetermined time period is shorter than a time interval from the recovery of the AC power source to a start of control to drop a ripple component of a voltage across the smoothing capacitor. a rectifier configured to rectify an input alternate current from an AC power source; a power factor corrector including a reactor (L25a, L25b, L25c) and a switching device (Q25a, Q25b, Q25c) which switches between accumulation and discharge of energy, based on an input voltage output from the rectifier, in and out of the reactor (L25a, L25b, L25c), and configured to be capable of performing a power factor correction operation by boosting the input voltage; a power converter connected to an output of the power factor corrector, and configured to generate output AC power (SU, SV, SW); and a controller configured to control the power factor correction operation by the power factor corrector, characterized in that the power factor corrector includes a smoothing capacitor provided close to an output of the reactor (L25a, L25b, L25c), and connected in parallel to the switching device (Q25a, Q25b, Q25c), and the controller is configured to: turn the switching device (Q25a, Q25b, Q25c) off so that the power factor correction operation stops, if an instantaneous voltage drop or an instantaneous power failure occurs in the AC power source while the power factor corrector is performing the power factor correction operation; leave the compressor driving without rest, if the instantaneous voltage drop or the instantaneous power failure occurs while the compressor is driving; leave the power factor correction operation stopped when the AC power source recovers; and permit the power factor corrector to perform the power factor correction operation, if the compressor continues driving from recovery of the AC power source through a predetermined time period; wherein the predetermined time period is shorter than a time interval from the recovery of the AC power source to a start of control to drop a ripple component of a voltage across the smoothing capacitor. turn the switching device (Q25a, Q25b, Q25c) off so that the power factor correction operation stops, if an instantaneous voltage drop or an instantaneous power failure occurs in the AC power source while the power factor corrector is performing the power factor correction operation; leave the compressor driving without rest, if the instantaneous voltage drop or the instantaneous power failure occurs while the compressor is driving; leave the compressor driving without rest, if the instantaneous voltage drop or the instantaneous power failure occurs while the compressor is driving; leave the power factor correction operation stopped when the AC power source recovers; and permit the power factor corrector to perform the power factor correction operation, if the compressor continues driving from recovery of the AC power source through a predetermined time period; wherein the predetermined time period is shorter than a time interval from the recovery of the AC power source to a start of control to drop a ripple component of a voltage across the smoothing capacitor.