Abstract: A constant voltage control method for a fuel cell vehicle includes: determining whether vehicle state information satisfies a cold start condition when the fuel cell vehicle is started; starting constant voltage control on a fuel cell when the vehicle state information satisfies the cold start condition; comparing an RPM of an air blower for supplying air to the fuel cell with a predetermined stop control condition; and terminating the constant voltage control on the fuel cell when the RPM of the air blower satisfies the predetermined control-stopping condition.

Abstract: A fuel cell system for modulating an offset of a hydrogen pressure sensor is provided. The fuel cell system includes a stack with a plurality of cells and each cells includes a first electrode to which hydrogen is supplied, a second electrode to which oxygen is supplied, and a membrane electrode assembly arranged between the first and second electrodes to produce electricity by reaction between the hydrogen and the oxygen. The hydrogen pressure sensor is connected to each cell to sense a pressure of the hydrogen supplied to the first electrode. A controller that which of the cells is supplied with insufficient pressure of hydrogen and modulates the offset of the hydrogen pressure sensor connected to the cell to which the hydrogen is supplied with insufficient pressure, to then supply the hydrogen to the first electrode at an appropriate pressure.

Abstract: An operation control method of a fuel cell system is provided that increases the output of a fuel cell stack by detecting and overcoming the cause of a performance limit when the stack reaches the performance limit during high-altitude operation of a fuel cell vehicle, thereby achieving higher stack performance and vehicle power performance. The method includes determining whether an operation state of the stack corresponds to a predetermined condition in which a stack output limit occurs by determining current operation state information of the stack. Additionally, operating pressure of an air pole is adjusted by changing an opening degree of an air pressure adjusting valve to a control command value based on the operation state of the stack when the operation state corresponds to the predetermined condition in which the stack output limit occurs.

Abstract: A method for diagnosing a water-containing state of a fuel cell stack includes steps of: applying an alternating current (AC) signal having a predetermined frequency to the fuel cell stack to calculate each of an electrolyte membrane impedance, an anode impedance, and a cathode impedance from an output voltage and an output current of the fuel cell stack corresponding to the AC signal; and diagnosing the water-containing state of the fuel cell stack on the basis of the electrolyte membrane impedance, the anode impedance, and the cathode impedance.

Abstract: A method for controlling startup of a fuel cell vehicle is provided. The method includes starting to adjust supply of hydrogen and air to a fuel cell and setting a control voltage of a side of a main bus end of a converter disposed between the main bus end and a high-voltage battery to a predetermined lowest control voltage. An output voltage of the side of the main bus end of the fuel cell and the control voltage of the side of the main bus end of the converter are then compared to adjust an amount of air supply to the fuel cell based on the comparison.

Abstract: A constant voltage control method for a fuel cell vehicle includes: determining whether vehicle state information satisfies a cold start condition when the fuel cell vehicle is started; starting constant voltage control on a fuel cell when the vehicle state information satisfies the cold start condition; comparing an RPM of an air blower for supplying air to the fuel cell with a predetermined stop control condition; and terminating the constant voltage control on the fuel cell when the RPM of the air blower satisfies the predetermined control-stopping condition.

Abstract: A method for controlling startup of a fuel cell vehicle is provided. The method includes starting to adjust supply of hydrogen and air to a fuel cell and setting a control voltage of a side of a main bus end of a converter disposed between the main bus end and a high-voltage battery to a predetermined lowest control voltage. An output voltage of the side of the main bus end of the fuel cell and the control voltage of the side of the main bus end of the converter are then compared to adjust an amount of air supply to the fuel cell based on the comparison.

Abstract: An operation control method of a fuel cell system is provided that increases the output of a fuel cell stack by detecting and overcoming the cause of a performance limit when the stack reaches the performance limit during high-altitude operation of a fuel cell vehicle, thereby achieving higher stack performance and vehicle power performance. The method includes determining whether an operation state of the stack corresponds to a predetermined condition in which a stack output limit occurs by determining current operation state information of the stack. Additionally, operating pressure of an air pole is adjusted by changing an opening degree of an air pressure adjusting valve to a control command value based on the operation state of the stack when the operation state corresponds to the predetermined condition in which the stack output limit occurs.

Abstract: A control method and system for reducing tip-in shock includes fixing a wheel with a wheel brake of a vehicle when an engine of the vehicle starts. A motor position sensor value is detected when a motor connected to the wheel through a plurality of gears is operated forward by a forward torque and a motor position sensor value when the motor is operated backward by a backward torque, by applying the forward torque and the backward torque to the motor with the wheel being fixed. An entire backlash generated between the plurality of gears is calculated on the basis of the motor position sensor values. A driving current for driving the motor is applied to the motor in accordance with the calculated entire backlash.

Abstract: A control method and system for reducing tip-in shock includes fixing a wheel with a wheel brake of a vehicle when an engine of the vehicle starts. A motor position sensor value is detected when a motor connected to the wheel through a plurality of gears is operated forward by a forward torque and a motor position sensor value when the motor is operated backward by a backward torque, by applying the forward torque and the backward torque to the motor with the wheel being fixed. An entire backlash generated between the plurality of gears is calculated on the basis of the motor position sensor values. A driving current for driving the motor is applied to the motor in accordance with the calculated entire backlash.

Abstract: A rear wheel housing reinforcement unit for a vehicle is provided in which connecting each rear wheel housings including an inner panel and an outer panel and reinforcing the rear wheel housings. The rear wheel housing reinforcement unit includes a quarter main panel configured to an upper portion of the each rear wheel housing, a roof rear rail connecting an upper portion of the each quarter main panel and a quarter reinforcement which is configured to an outer side of the quarter main panel and of which an upper end is connected to an end of the roof rear rail.

Abstract: A rear suspension cross member mounting structure includes a rear floor side member with a 4WD rear cross member mounting hole and a 2WD rear cross member mounting hole, and a reinforcement bracket with a slot corresponding to both the 4WD rear cross member mounting hole and the 2WD rear cross member mounting hole. The structure may further include a bolt, passing through the reinforcement bracket and the rear floor side member to attach the rear cross member to the structure. The bolt may pass sequentially through the reinforcement bracket, the rear floor side member, and the rear cross member, and then engage with a nut provided below the rear cross member.

Abstract: The invention provides for an exterior air intake system in an engine compartment of a vehicle wherein the exterior air can be guided smoothly into an air cleaner. The engine compartment of a vehicle includes: a front-end module that is separated from an engine by a predetermined distance and that is disposed to a front end of a vehicle body; an air cleaner that is positioned near to a side of the engine; a first air duct that connects the air cleaner to the engine; and a second air duct for guiding an exterior air into the air cleaner, wherein the first end of the second air duct is connected to the air cleaner and the second end of the second air duct is positioned to a center of an upper portion of the front-end module.

Abstract: A lower arm mounting structure of a vehicle suspension includes a first mount mounted to a wheel of a vehicle, a second mount mounted to a sub frame side member at one side of the sub frame side member, and a third mount mounted to the sub frame side member at the other side of the sub frame side member. The third mount is fastened to the sub frame side member at two points spaced apart from each other in a longitudinal direction of the sub frame side member by bolts. The lower arm mounting structure prevents the mounts from being displaced during the cornering of the vehicle. Accordingly, it is possible to reduce or eliminate the phenomenon that the front part of the vehicle is inclined, and to achieve an enhancement in vehicle handling performance.

Abstract: A package tray of a vehicle includes a first reinforcing member installed to a woofer mount of a center panel and supported by a rear member and a second reinforcing member installed to the rear member to correspond to the woofer mount of the center panel in the front-to-rear direction. Thus, stiffness is increased so that noise, caused by vibration and/or tremble generated when a woofer outputs sound waves, can be minimized.

Abstract: A mounting portion structure of a propeller shaft center bearing in a Rear-Wheel Drive (RWD) vehicle where the engine power is transmitted to the rear wheels by using the propeller shaft includes a tunnel formed at the center of a center floor panel along the longitudinal direction of the vehicle. A mounting bracket is equipped at the tunnel and is mounted with the center bearing. A pocket groove is formed at the mounting bracket for rendering a closed box with the tunnel, and a pipe nut is equipped at the pocket groove.

Abstract: A rear suspension cross member mounting structure includes a rear floor side member with a 4WD rear cross member mounting hole and a 2WD rear cross member mounting hole, and a reinforcement bracket with a slot corresponding to both the 4WD rear cross member mounting hole and the 2WD rear cross member mounting hole. The structure may further include a bolt, passing through the reinforcement bracket and the rear floor side member to attach the rear cross member to the structure. The bolt may pass sequentially through the reinforcement bracket, the rear floor side member, and the rear cross member, and then engage with a nut provided below the rear cross member.

Abstract: A mounting structure of a steering column for a vehicle is provided with a column mounting bracket coupling the steering column to a cowl cross-member. A pedal bracket is coupled to a dash panel of the vehicle and a contact prevention part is provided at the column mounting bracket so that contact between an inner end of the pedal bracket and the column mounting bracket is minimized. Therefore, injuries to a driver and noise from vibration are minimized along with an increase in workability in manufacturing and assembly of the pedal structure.

Abstract: The invention provides for an exterior air intake system in an engine compartment of a vehicle wherein the exterior air can be guided smoothly into an air cleaner. The engine compartment of a vehicle includes: a front-end module that is separated from an engine by a predetermined distance and that is disposed to a front end of a vehicle body; an air cleaner that is positioned near to a side of the engine; a first air duct that connects the air cleaner to the engine; and a second air duct for guiding an exterior air into the air cleaner, wherein the first end of the second air duct is connected to the air cleaner and the second end of the second air duct is positioned to a center of an upper portion of the front-end module.

Abstract: A bumper beam includes a metallic center beam mounted with a plurality of vertical members each integrally crossed by a horizontal member. A plastic outer beam encompasses an external side of the center beam and a plurality of ribs are mounted at the outside of the plastic outer beam. The bumper beam features of a bumper beam needed in times of a low speed collision and a high speed collision between the vehicle and a pedestrian. As a result, injuries to the pedestrian can be reduced during the low speed collision and an impact absorption performance of the vehicle can be maximized during the high speed collision. Thereby, safety of the pedestrian and occupants inside the vehicle are increased.