Abstract: A virtual simulator and a building management system including the same are provided.

Abstract: The present invention provides a modified cross-section hollow fiber, wherein the fiber comprises a hollow part, a shape maintaining part and a volume control part, the volume control part can have a shape protruding in the direction opposite to the center of the fiber, and an end part has a round shape.

Abstract: A dual inverter system to drive a motor in an electronic apparatus and a method of controlling the same include a first inverter connected to one side of a stator winding of the motor to modulate a pulse width and to adjust power supplied to the motor, a second inverter connected to the other side of the stator winding of the motor to modulate a pulse width and to adjust power supplied to the motor, a first current detector connected to the first inverter to detect a current flowing in the first inverter, a second current detector connected to the second inverter to detect a current flowing in the second inverter, and a controller to control the motor by controlling a pulse-width modulation (PWM) signal applied to the first inverter or the second inverter based on the current flowing in at least one of the first inverter and the second inverter.

Abstract: A sensorless control apparatus may include: a speed command unit configured to output a speed command to an electric motor; a current detector unit configured to detect electric current flowing through the electric motor if a voltage being output according to the speed command is supplied to the electric motor; a rotor angle calculation unit configured to calculate a magnetic flux of a rotor of the electric motor based on the detected electric current and the voltage being output according to the speed command, and to calculate an angle of the rotor from the calculated magnetic flux; and/or an out-of-step sensing unit configured to sense an out-of-step of the rotor according to a comparison of the calculated angle of the rotor with an angle of the rotor estimated based on a sensorless control algorithm.

Abstract: A dual inverter system to drive a motor in an electronic apparatus and a method of controlling the same include a first inverter connected to one side of a stator winding of the motor to modulate a pulse width and to adjust power supplied to the motor, a second inverter connected to the other side of the stator winding of the motor to modulate a pulse width and to adjust power supplied to the motor, a first current detector connected to the first inverter to detect a current flowing in the first inverter, a second current detector connected to the second inverter to detect a current flowing in the second inverter, and a controller to control the motor by controlling a pulse-width modulation (PWM) signal applied to the first inverter or the second inverter based on the current flowing in at least one of the first inverter and the second inverter.

Abstract: A sensorless control apparatus may include: a speed command unit configured to output a speed command to an electric motor; a current detector unit configured to detect electric current flowing through the electric motor if a voltage being output according to the speed command is supplied to the electric motor; a rotor angle calculation unit configured to calculate a magnetic flux of a rotor of the electric motor based on the detected electric current and the voltage being output according to the speed command, and to calculate an angle of the rotor from the calculated magnetic flux; and/or an out-of-step sensing unit configured to sense an out-of-step of the rotor according to a comparison of the calculated angle of the rotor with an angle of the rotor estimated based on a sensorless control algorithm.