Hyundai Motor Company

Postech Academy-industry Foundation

Kia Corporation

Jaesik Yang

Kitae Yeom

Sung Won Kim

Tae Won Hwang

Hong-Young Lee

Kwang-Hee Nam

Sungwon Kim

Jun Woo Kim

Seonghyeon Kim

Taewon Hwang

Jae Man Lim

Junwoo Kim

A sound control device controls an interior sound in a vehicle based on a slope of a road on which the vehicle travels. The sound control device includes: a sound canceling circuit for generating a first correcting sound for lowering a level of an interior sound measured in the vehicle; a sound boosting circuit for generating a second correcting sound for increasing the level of the interior sound; and a controller for setting a level of a second target sound to be less than a level of a first target sound. In particular, the second target corresponds to a ramp in which an absolute value of the slope is greater than a reference value and the first target sound corresponds to a flatland in which the absolute value of the slope is equal to or less than the reference value.

Method for controlling interior sound in a vehicle and a device for controlling sound providing the method

A bearing unit of a turbocharger may be disposed on an inner side of a space in a center housing and carry axial load of a rotary shaft connecting a turbine wheel, a compressor wheel, and an electric motor. The bearing unit may include a bearing body fastened to a side of the center housing and has a through-hole substantially at a center of the bearing body, and a coupling disposed in the through-hole and on the rotary shaft, having a stepped portion in which the bearing body is inserted, and forming an oil chamber with the bearing body.

Bearing unit of turbo-charger

A rotor assembling method for a turbo-charger may include washing and preparing components of a rotor having a connector, a permanent magnet, end caps, a retention ring, and a center pipe, inserting the connector into the permanent magnet, thermally inserting one or more end caps into the connector by cooling the connector and heating the one or more end caps under a first high-temperature condition for a first predetermined time to form a permanent magnet assembly, thermally inserting the permanent magnet assembly into the retention ring by cooling the permanent magnet assembly and heating the retention ring under a second high-temperature condition for a second predetermined time to form a rotor assembly, thermally inserting the center pipe into the rotor assembly by heating the rotor assembly under a third high-temperature condition for a third predetermined time to form a rotor assembling body, and post processing the rotor assembling body.

Method of assembling a rotor for an electric turbo-charger

A sensorless control method and system for a motor are provided. The includes a back EMF observer that is configured to estimate a back EMF of the motor and an angle error calculator that is configured to calculate an electrical angle error considering iron loss of the motor based on the back EMF estimated by the back EMF observer. An angle error compensator is configured to compensate the electrical angle error calculated by the angle error calculator. An electrical angle for compensating the calculated electrical angle error is obtained through simulation or experiment for the motor. In addition, a PLL controller is configured to receive the compensated electrical angle to estimate an actual angle by reducing the electrical angle error due to the iron loss, and to operate the motor based on the estimated actual angle.

Sensorless control method and system for motor

A turbocharger system includes a compressor that is connected with a turbine operated by an exhaust gas by a rotary shaft and compresses and supplies external gas to a combustion chamber of an engine, an intercooler and a throttle valve disposed in an intake line connecting the compressor with the combustion chamber of the engine, a branch line connecting an intake line between the compressor and the intercooler with an intake line between the intercooler and the throttle valve, a shutoff valve disposed in the branch line to selectively open/close the branch line, and an engine control unit controlling the operation of the shutoff valve.

Turbo-charger system

A sensorless control method for a motor performed by a sensorless controller including a back electromotive force (EMF) observer and a phase locked loop (PLL) controller, includes: estimating a back EMF of the motor using the back EMF observer; calculating an electrical angle error in accordance with iron loss of the motor based on the estimated back EMF; and compensating for the calculated electrical angle error, inputting the compensated electrical angle error into the PLL controller to estimate an actual angle, and controlling the motor based on the estimated actual angle.

Growing community of inventors

Seoul, South Korea

Jaesik Yang