• 오토저널
• /
• 제14권4호
• /
• pp.61-67
• /
• 1992

The ignition timing feedback control system was studied to enhance the engine power and to reduce the fuel consumption by optimizing the spark timing. The signal of a piezo-electric vibration transducer attached to the engine block was compared with that of a pressure transducer in order to determine the knock intensity. With the result of comparison the ignition timing feedback control system which detect the knock and correct the spark timing was set up. The ignition could be more advaced with this control system than the existing system without the continuous knocking, therefore the engine torque was increased.

• Journal of Advanced Marine Engineering and Technology
• /
• 제17권5호
• /
• pp.33-43
• /
• 1993

Recent marine propulsion diesel engines tend to become slower in speed and longer in stroke for the higher engine efficiency, and in these long stroke and slow speed engines the digital governors are highly recommended to be used. But, in the present digital governors only the feedback of the engine rpm-signal is used for the engine speed control and it does not work so effectively when the load variation is large. In this paper, a new method is proposed to improve the speed control performance in a diesel engine, by adding the torque feedback loop to the present digital governor which uses the rpm feedback PID controller only. And also a method is proposed to adjust the parameters of the PID controller optimally.

• 한국분무공학회지
• /
• 제24권4호
• /
• pp.163-170
• /
• 2019

In this study, feedback logic using dual O₂ sensor values were developed to increase the purification capability of a three-way catalyst (TWC) in a compressed natural gas (CNG) engine. A heavy-duty inline 6-cylinder engine was used and the CNG was supplied to the engine through a mixer. This study consists of two main parts, namely, the proportional integral (PI) control with a front O₂ sensor and the feedback control with dual O₂ sensors. In the PI control experiment, effects of various parameters, such as P gain, I gain, and lean delay, on the TWC capability were identified. Based on the results of the PI control experiment, the feedback logic using dual O₂ sensor values were developed. In both cases, the nitrogen oxides (NO_X) emissions were nearly zero. However, the carbon monoxide (CO) emissions were reduced significant in the feedback logic with dual O₂ sensors than in the PI control with the front O₂ sensor.

• 한국추진공학회지
• /
• 제2권2호
• /
• pp.38-46
• /
• 1998

본 연구에서는 강인성 제어의 한 분야인 LQG용 observer를 이용한 단축 터보 젯 엔진의 RPM 속도제어에 대하여 이론을 전개하고 실제 엔진 모델에 대한 시뮬레이션을 실시하였다. 일반적인 시불변 선형연속 시스템에 대하여 상태 출력 궤환 제어기를 설계하여 asymptotic stability를 얻기 위한 충분 조건을 도출하고, 다음으로 실제 터보 젯 엔진으로부터 구한 시스템 모델에 대하여 observer를 이용하여 추적 제어를 실시하였다. 실제 엔진과 더 가까운 상황을 재현하기 위해 제어 입력부의 saturation을 함께 고려하였다.

• 한국소음진동공학회논문집
• /
• 제20권12호
• /
• pp.1176-1182
• /
• 2010

Vibrations caused by automobile engine are absorbed mostly by a passive-type engine mount. However, user specifications for automobile vibrations require more stringent conditions and higher standard. Hence, active-type engine mount have been developed to cope with such specifications. The active-type engine mount consists of sensor, actuator and controller where a control algorithm is implemented. The performance of the active engine mount depends on the control algorithm if the sensor and actuator satisfies the specification. The control algorithm should be able to suppress persistent vibrations caused by the engine which are related to engine revolution. In this study, three control algorithms are considered for suppressing persistent vibrations, which are the positive position feedback control algorithm, the strain-rate feedback control algorithm, and the modified higher harmonic control algorithm. Experimental results show that all the control algorithms considered in this study are effective in suppressing resonant vibrations but the modified higher harmonic controller is the most effective controller for non-resonant vibrations.

• 한국자동차공학회논문집
• /
• 제11권5호
• /
• pp.163-169
• /
• 2003

Modeling of engine-generator system and its control responses are investigated using high performance generator controller. The nonlinear engine is modeled using mean torque production model based on experimental engine map. In case of diesel engine. the amount of injected fief is decided by engine controller depending on the APS(Acceleration Position Sensor) value. An electromechanical generator model contains electrical circuits and moment of inertia. The generator controller maximizes the performance of generator using decoupling and linearized current feedback control. The generator control system consists of 3-phase IGBT inverter and controller board based on 32 bit floating point DSP. Field oriented control algorithm with digital current feedback control at 10kHz sampling enabled high performance torque and speed control of induction machine. Not only the steady state but also the transient state responses can be evaluated through a batch test of the engine generator system. Developed engine and generator modeling and control can be utilized in various applications such as Series Hybrid Electric Vehicle(SHEV), engine-generator for emergency, and other hybrid generation systems.

• 한국추진공학회지
• /
• 제24권2호
• /
• pp.52-60
• /
• 2020

본 논문에서는 개방형 액체로켓엔진의 제어 알고리즘을 다룬다. 이를 위해 엔진의 각 구성품들을 기준으로 수학적 모델링을 하였으며 추력제어를 위하여 연소실 압력을 피드백하여 제어시스템을 구축하였다. 제어시스템을 위하여 최대추력 상태에서 선형 모델을 이용하여 최적 출력피드백 LQ 추종 제어기를 설계하였으며 시뮬레이션을 통해 제어기의 성능을 검증하였다.

• 한국분무공학회지
• /
• 제5권3호
• /
• pp.9-16
• /
• 2000

In a SI engine, three-way catalyst converter has the best efficiency when A/F ratio is near the stoichiometry. The feedback control using oxygen sensors in the commercial engine has limits caused by the system delays. So it is necessary to control fuel quantity in accordance with intake air amount in order to reduce exhaust emission and improve the specific fuel consumption. Precise A/F ratio control requires measurement of air amount with respect to the cylinder and injection fuel according to the air amount In this paper, we applied nonlinear fuel injection model and developed the algorithm of A/F ratio control. This algorithm includes the methods of measurement of transient air mass flowing into each cylinder, of calculation of injection pulse width for measured air mass, and the method of feedback and engine control by using lambda sensor. Also we developed control program for IBM-PC by using C++ Builder, and tested it in the commercial engine.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2010년도 추계학술대회 논문집
• /
• pp.324-329
• /
• 2010

Vibrations caused by automobile engine are absorbed mostly by a passive-type engine mount. However, user specifications for automobile vibrations require more stringent conditions and higher standard. Hence, active-type engine mount have been developed to cope with such specifications. The active-type engine mount consists of sensor, actuator and controller where a control algorithm is implemented. The performance of the active engine mount depends on the control algorithm if the sensor and actuator satisfies the specification. The control algorithm should be able to suppress persistent vibrations caused by the engine which are related to engine revolution. In this study, three control algorithms are considered for suppressing persistent vibrations, which are the positive position feedback control algorithm, the strain-rate feedback control algorithm, and the modified higher harmonic control algorithm. Experimental results show that all the control algorithms considered in this study are effective in suppressing resonant vibrations but the modified higher harmonic controller is the most effective controller for non-resonant vibrations.

• 한국추진공학회지
• /
• 제20권3호
• /
• pp.37-53
• /
• 2016

본 논문에서는 다단 연소방식의 액체로켓엔진인 우주왕복선 주 엔진(Space Shuttle Main Engine, SSME)의 제어 알고리즘을 다룬다. 이를 위해 SSME의 각 구성품들을 기준으로 크게 7가지 분류로 나누어 구성하여 수학적 모델링을 하였으며 순항상태 추력을 기준으로 Rated Propulsion Level (RPL)에 따른 정상상태 작동점을 구하였다. 폐루프 시스템을 위하여 순항상태인 RPL 104% 조건에서의 선형모델을 이용하여 최적 출력피드백 LQR 제어기 설계를 하였으며 시뮬레이션을 통해 제어기의 성능을 검증하였다.