Characteristics of a Small Engine Equipped with an Electromagnetic Valve Actuation System

1998 ◽  
Author(s):  
Daniel J. Podnar ◽  
John T. Kubesh
Keyword(s):  
Electromagnetic Valve ◽  
Actuation System ◽  
Valve Actuation

Electromagnetic Valve Actuation System With Two Configurations

2009 ◽  
Author(s):  
Rudolf Seethaler ◽  
Konrad Duerr
Keyword(s):  
High Speed ◽  
Digital Simulation ◽  
Valve Train ◽  
Electromagnetic Valve ◽  
High Speed Engine ◽  
Actuation System ◽  
Control Scheme ◽  
Cam Profile ◽  
Actuation Devices ◽  
Valve Actuation

Electromagnetic valve actuation systems for automotive combustion engines must provide extremely fast valve motion when the engine speed is high, but they also need to ensure low valve seating velocities during engine idle. These two constraints are difficult to combine in conventional spring assisted electromagnetic valve actuation devices that operate at a fixed resonance frequency. This paper focuses on a mechanism with two distinct configurations for low and high speed engine operations respectively. The mechanism is based on two pivoting cams. The synthesis of the cam profile ultimately determines the performance of the actuation system. An algorithm is presented that provides a time optimum cam profile for the high speed cam. The low speed cam is designed to allow for servo control of the valve system. A control scheme that aims to minimize electric losses in the drive system is also introduced. Both the cam synthesis algorithms and the control algorithm are applied to a typical automotive valve train and a digital simulation is used to validate the effectiveness of the mechanical cam design and control scheme.

Effects of design and operating parameters on the static and dynamic performance of an electromagnetic valve actuator

2003 ◽  
Vol 217 (3) ◽  
pp. 193-201 ◽  
Author(s):  
S-H Park ◽  
J Lee ◽  
J Yoo ◽  
D Kim ◽  
K Park
Keyword(s):  
Simulation Model ◽  
New Technology ◽  
Dynamic Performance ◽  
Operating Parameters ◽  
Computer Simulation Model ◽  
Neutral Position ◽  
Electromagnetic Valve ◽  
Actuation System ◽  
Si Engines ◽  
Actuation Devices

The electromagnetic valve (EMV) actuation system is a new technology for improvement in fuel effciency and reduction in emissions in spark ignition (SI) engines. It can provide more flexibility in valve event control compared with conventional variable valve actuation devices. However, a more powerful and effcient actuator design is needed for this technology to be applied in mass production engines. This paper presents the effects of design and operating parameters on the static and dynamic performances of the actuator. Employing the finite element method (FEM), the flow pattern of the magnetic flux is analysed and the resultant magnetic forces of several cases of core and armature designs are calculated. A computer simulation model has been set up to identify the dynamic behaviour of the EMV system. The effects of external disturbances such as cylinder pressure, armature neutral position and current supply time are also analysed. To verify the accuracy of the simulation model, an experimental study is also carried out on a prototype actuator. It is found that there is relatively good agreement between the experimental data and the results from the simulation model. The newly designed actuator is successfully operated on the test bench up to about 6000 r/min, which is the range of rated speed of most production SI engines. Through the whole speed range, the actuator maintains good performance in valve timing and event control.

Development of a variable mode valve actuation system for a heavy-duty engine

2020 ◽  
Vol 234 (10-11) ◽  
pp. 2618-2633
Author(s):  
Yang Wang ◽  
Wuqiang Long ◽  
Jingchen Cui ◽  
Hua Tian ◽  
Xiangyu Meng ◽  
...  
Keyword(s):  
Solenoid Valve ◽  
Valve Lift ◽  
Heavy Duty ◽  
Driving Mode ◽  
Actuation System ◽  
Failure State ◽  
Body Dynamics ◽  
Variable Mode ◽  
Multi Body ◽  
Valve Actuation

A new variable mode valve actuation system for a heavy-duty engine was proposed and designed in this paper. The variable mode valve actuation system can significantly enhance braking safety and improve fuel economy and emission of heavy-duty engines through flexible switching among four-stroke driving mode, two-stroke compression-release braking mode, and cylinder deactivation mode on a conventional four-stroke engine. The switching was controlled by four-stroke driving modules and two-stroke braking modules, both of which have two operation states: effective state and failure state. For the control of the multi-cylinder engine, all cylinders can be divided into several groups, and all the four-stroke driving modules in the same group were controlled by one solenoid valve, as well as all the two-stroke braking modules were controlled by another solenoid valve. A hydraulic-mechanical multi-body dynamics model was established to investigate the switching response of the variable mode valve actuation system. The results indicated that when the engine operated at 2000 r/min, the switching of the four-stroke driving module and the two-stroke braking module required 30 °CA and 101 °CA at most, respectively. In addition, to avoid the conflict between the four-stroke driving valve lift and the two-stroke braking valve lift, the switching between the four-stroke driving mode and the two-stroke compression-release braking mode must have a reasonable sequence. The variable mode valve actuation system has an excellent switching response and it is convenient for the control of the multi-cylinder engine. Therefore, the variable mode valve actuation system has a good application prospect for heavy-duty engines.

Analysis and optimization of a variable mode valve actuation system

2020 ◽  
pp. 146808742090599
Author(s):  
Yang Wang ◽  
Jingchen Cui ◽  
Xiangyu Meng ◽  
Jiangping Tian ◽  
Hua Tian ◽  
...  
Keyword(s):  
Thermal Management ◽  
Flow Rate ◽  
Outlet Temperature ◽  
Brake Specific Fuel Consumption ◽  
Cylinder Pressure ◽  
Heavy Duty ◽  
Cylinder Deactivation ◽  
Actuation System ◽  
Variable Mode ◽  
Valve Actuation

Braking safety of heavy-duty engines has always been the focus of the research, and the fuel economy and after-treatment thermal management during low-load operation of heavy-duty engines have also received much attention in recent years. A variable mode valve actuation system which can realize switching between four-stroke driving, two-stroke compression release braking and cylinder deactivation modes on a traditional four-stroke engine was proposed in this article. Two-stroke compression release braking mode of the variable mode valve actuation system can greatly enhance the braking safety, while the overload of valve train was a great challenge, especially during the release event. The effects of different release opening timing on cylinder pressure and the braking performance were studied. The results indicated that a higher cylinder pressure does not always lead to higher braking power. When the release opening timing was advanced by 6 °CA, the braking power reduced by only 9 kW (2.65%) at 1900 r/min compared with the initial value, while the maximum cylinder pressure reduced by 11.4 bar (20.8%). Besides, the variable mode valve actuation system can realize alternate three-cylinder cylinder deactivation mode on a six-cylinder turbocharged engine, which can improve the brake-specific fuel consumption by 14.67% and increase the turbine outlet temperature by 63.6 °C and reduce the exhaust flow rate by 50.66% at lightly load idle. Meanwhile, when the engine load is less than 50% at the rated speed, the three-cylinder cylinder deactivation mode can improve the brake-specific fuel consumption, increase the turbine outlet temperature and reduce the exhaust flow rate. The increase of the turbine outlet temperature and the decrease of the exhaust flow rate are very beneficial to improve the efficiency of the after-treatment thermal management of heavy-duty engines.

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