Abstract: The present invention relates to an inverter-controlling device. The inverter-controlling device include a main controller configured to generate a predetermined command current; a comparison module configured to calculate a difference between the command current and an output current of an inverting module; a current controller configured to perform a proportional-integral (PI) control based on the difference; and a frequency estimation module configured to estimate a rotation speed of a motor based on a current response to the command current while the command current is injected to the current controller, wherein the main controller is further configured: when a flying start operation of the inverting module begins, to set an output frequency of the inverting module based on the rotation speed of the motor estimated by the frequency estimation module.

Abstract: Disclosed herein are a method for controlling a medium-voltage inverter, and a system including the same. The system includes a motor, a medium-voltage inverter driving the motor, a control unit configured to control an output voltage from the medium-voltage inverter, and an output voltage measuring unit configured to measure counter electromotive force data of the motor including a voltage and a frequency of the counter electromotive force, and transmitting it to the control unit. The control unit generates the output voltage based on the measured counter electromotive force data to re-drive the motor when the output voltage measuring unit completes the measurement of the counter electromotive force data.

Abstract: The present invention relates to an inverter-controlling device. The inverter-controlling device include a main controller configured to generate a predetermined command current; a comparison module configured to calculate a difference between the command current and an output current of an inverting module; a current controller configured to perform a proportional-integral (PI) control based on the difference; and a frequency estimation module configured to estimate a rotation speed of a motor based on a current response to the command current while the command current is injected to the current controller, wherein the main controller is further configured: when a flying start operation of the inverting module begins, to set an output frequency of the inverting module based on the rotation speed of the motor estimated by the frequency estimation module.

Abstract: Disclosed herein are a method for controlling a medium-voltage inverter, and a system including the same. The system includes a motor, a medium-voltage inverter driving the motor, a control unit configured to control an output voltage from the medium-voltage inverter, and an output voltage measuring unit configured to measure counter electromotive force data of the motor including a voltage and a frequency of the counter electromotive force, and transmitting it to the control unit. The control unit generates the output voltage based on the measured counter electromotive force data to re-drive the motor when the output voltage measuring unit completes the measurement of the counter electromotive force data.

Abstract: An inverter system includes: an inverter configured to receive utility AC power and step it up to a high-voltage power necessary for operation of a motor and supply the high-voltage power to the motor; a switch connected between the inverter and the motor and configured to be turned on and off such that an output voltage from the inverter is supplied to the motor or interrupted; a current detector configured to detect an output current from the inverter; and a controller configured to control the inverter system so that the inverter is interrupted if an output current value detected by the current detector is smaller than a predetermined reference current value for more than a predetermined reference duration.

Abstract: An inverter system includes: an inverter configured to receive utility AC power and step it up to a high-voltage power necessary for operation of a motor and supply the high-voltage power to the motor; a switch connected between the inverter and the motor and configured to be turned on and off such that an output voltage from the inverter is supplied to the motor or interrupted; a current detector configured to detect an output current from the inverter; and a controller configured to control the inverter system so that the inverter is interrupted if an output current value detected by the current detector is smaller than a predetermined reference current value for more than a predetermined reference duration.