• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.26 no.2
• /
• pp.195-202
• /
• 2016

In this study, a concept of active sound enrichment (ASE) control system was implemented and demonstrated for improving engine sound quality inside the cabin of a passenger car during acceleration. Unlike the active noise control cancels the noise for disturbance rejection, the ASE adds additional sound to the noise for tracking control. This approach requires a new algorithm to provide additional artificial sound to the original engine sound using active control strategy to achieve a target sound profile, which is predefined to satisfy required interior sound quality. The ASE algorithm was implemented in a digital controller dSPACE DS1401 and real-time control experiment was accomplished in an actual car. The ASE control results show that the actively enriched sound of each engine order against RPM tracks the target profiles precisely and quickly and improves the discontinuity, the level ratios and the sound pressure level of each engine order. Thus it is anticipated the ASE system can be applied for the improvement of the engine sound quality inside the cabin during acceleration.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.2
• /
• pp.500-510
• /
• 1996

This paper presents a new prototype of an engine mount for a passenger vehicle featuring ER(elector-rheological) fluids and piezoactuators. Conventional rubber mounts and various types of passive or semi-active hydraulic engine mounts have their own functional aims on the limited frequency band in the board engine operating frequency range. However, the proposed engine mount covers all frequency range of the engine operation. A mathematical model of the proposed engine mount is derived using the bond graph method which is inherently domain, the ER fluid is activated upon imposing electric field for vibration isolation while the piezoactuator. Computer control electric fluid for the ER fluid H.inf. cotrol technique is adopted for the piezoactuator. Computer simulation is undertaken in order to demonstrate isolation efficiency of the engine mount over wide operating frequency range.

• Journal of Institute of Control, Robotics and Systems
• /
• v.7 no.6
• /
• pp.502-508
• /
• 2001

In this paper, slack is computed from a comparison of the cable pay out rate and the ship ground speed in accordance with laying conditions, and the speed controller of the cable engine based on an H(sub)$\infty$ servo control id designed for adjusting the cable engine in order to lay a desired amount of slack. The controller is designed for robust tracking of the cable engine under disturbances. The performance of the designed controller is evaluated by computer simulation, and, consequently, a feasibility study for laying the submarine cable stably is done through analyzing simulation results.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.28 no.3
• /
• pp.262-273
• /
• 1992

In this study, we selected a DC servo motor as an actuator of the marine diesel engine governor and constructed the position control system of the DC servo motor using the algorithm proposed by authors. Next, we proposed an another method to construct an adaptive control system for marine diesel engine by regarding the controlled system including the DC servo motor as a second order controlled system and verified the validity of this method through the real time control responses. Finally, the results have shown a good response characteristic.

• Journal of Advanced Marine Engineering and Technology
• /
• v.25 no.3
• /
• pp.644-654
• /
• 2001

In this paper, an electronic control unit of the automobile engine for optimal fuel injection an spark timing control has been designed and developed. This system includes hardware and software for a precise control of fuel injection and ignition timing. Especially, the crank angle sensor provides two separate signals: One is the position signal (POS) which indicates 180 degree pulses per revolution, and the other is the reference signal (REF) that represents each cylinder individually. Consequently, the developed engine control system has been able to control fuel injection and ignition timing more quickly and accurately. Through the experiment, it has been found that the fuel injection duration and the position of MBT have been influenced by coolant temperature, air flow rate and engine speed.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.5 no.6
• /
• pp.215-221
• /
• 1997

The ability of the engine starting performance of conventional ignition system being currently used in automobile gasoline engine is investigated, and the method of improving is discussed and experimented. The conventional ignition system cannot obtain high ignited voltage because its current is limited by decreasing of terminal voltage of battery at starting the engine also causes irregularity in the starting engine. This paper shows that problem can be improved practically by control of ignition energy properly according to the engine speed, consequently this experimental ignition system can eliminate to remarkable extent the function of the engine starting, and also enhance the performance of the engine at high speed.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.4 no.3
• /
• pp.83-94
• /
• 2000

A systematic humidity correction technique that can be used for any type of engine control mode is developed to predict the variation of engine performance due to inlet humidity. Limitation of conventional method is rot identified and then, a new method is proposed to take into account the humidity effects on each engine component characteristics and to find the variation of equilibrium running point through a re-match process between the components with a given engine control variable depending on the humidity of inlet. Comparisons are made between two methods for a single spool gas turbine engine, and it was found that the conventional method leads to invalid correction when a physical variable such as rotational speed is controlled for engine operation in humid environment. It was also found that the accuracy of the conventional method depends on the engine control mode and the engine configuration whereas the proposed method can be used for any type of engine control mode and engine configuration.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.19 no.5
• /
• pp.14-21
• /
• 2011

In diesel engines, accurate EGR control is important due to its effect on nitrogen oxide and particulate matter emissions. Conventional EGR control system comprises a PI feedback controller for tracking target air mass flow and a feedforward controller for fast response. Physically, the EGR flow is affected by EGR valve lift and thermodynamic properties of the EGR path, such as pressures and temperatures. However, the conventional feedforward control output is indirectly derived from engine operating conditions, such as engine rotational speed and fuel injection quantity. Accordingly, the conventional feedforward control action counteracts the feedback controller in certain operating conditions. In order to improve this disadvantage, in this study, we proposed feedforward EGR control algorithm based on a physical model of the EGR system. The proposed EGR control strategy was validated with a 3.0 liter common rail direct injection diesel engine equipped with a DC motor type EGR valve.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.25 no.1
• /
• pp.68-76
• /
• 2021

The series hybrid system targeted in this study uses a reciprocating engine, a generator, and a battery as a main power source for the unmanned aerial vehicle. The generator is directly connected to the drive shaft of the reciprocating engine, and the operating characteristics of the reciprocating engine-generator set were confirmed through ground integration tests. In this study, based on the test results, a control logic is proposed an efficient use of the reciprocating engine-generator power and battery power. Also, the power variations of the reciprocating engine-generator and battery according to the logic were verified through simulation. As a result, it was confirmed that the engine-generator power supplied the power required for propulsion along with the battery power by the proposed control logic.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.291-295
• /
• 2004

New valve driving system to control for the best volumetric efficiency at each load of an internal combustion engine within one engine cycle has been developed. The system needs to reduce pumping loss that cause by throttle valve during the intake valve is opened. In this system the intake valve is driven by a linear DC electromagnetic actuator which is controlled by personal computer. The result is compared both installed and uninstalled actuator into the cylinder head. By both of experimental and numerical calculation, the responsibility of the valve driving system to the engine speed was examined