INVERTER CONTROL APPARATUS AND METHOD THEREOF

The present invention relates to an inverter control device and a control method thereof and specifically, to an inverter control device and a control method thereof which stably operates a three-phase motor using a small capacitor on a direct current terminal. The inverter control device by one embodiment of the present invention controls an inverter in which a direct current terminal voltage pulsates with a double frequency of a system frequency. The inverter control device comprises a current sensing unit for sensing an output current value of the inverter; a voltage sensing unit for sensing a direct current terminal voltage value of the inverter; and a control unit for producing an average value of a rotator standard q-axis current boundary value which is periodically changed based on the output current value and the direct current terminal voltage value, and producing a current command value based on the average value of the rotator standard q-axis current boundary value, and driving a three-phase motor based on the current command value. According to the present invention, the inverter control device stably variable speed-controls a motor using a small capacitor on a direct current terminal of the inverter and improves the reliability of an inverter circuit. Also, the inverter control device eliminates a circuit to initially charge a capacitor using the small capacitor. [Reference numerals] (7) Voltage sensing unit; (8) Gate driver; (9) Control unit