Power converter, motor driving apparatus, and refrigeration cycle applied apparatus

A power converter comprising:

• a rectifier and booster to rectify first alternating-current power supplied from a commercial power supply and boost a voltage of the first alternating-current power;
• a capacitor connected to an output end of the rectifier and booster;
• an inverter connected across the capacitor, to convert power output from the rectifier and booster and the capacitor into second alternating-current power, and output the second alternating-current power to a device equipped with a motor;
• and
• a controller to reduce a current flowing through the capacitor by controlling an operation of the rectifier and booster and by controlling an operation of the inverter such that the inverter outputs, to the device, the second alternating-current power containing a ripple dependent on a ripple of power flowing from the rectifier and booster rectifying and boosting unit into the capacitor, wherein
• the controller determines an operation mode in accordance with a load state that is an operating state of the inverter, the motor, and the device, and
• the operation mode is a combination of presence or absence of each of:
• an operation of the rectifier and booster;
• vibration reduction control that reduces vibration of the motor or the device;
• overmodulation control of the inverter;
• constant torque control on the motor;
• and power supply ripple compensation control that reduces a charge/discharge current through the capacitor.