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211.
Fault detection method for electric parking brake (EPB) systems with sensorless estimation using current ripples 总被引:1,自引:0,他引:1
C. W. Lee H. B. Chung Y. O. Lee C. C. Chung Y. S. Son P. Yoon 《International Journal of Automotive Technology》2010,11(3):387-394
A fault detection method with parity equations is proposed in this paper. Due to its low cost implementation, the velocity
of the motor is not measurable in electric parking brake (EPB) systems. Therefore, residuals are not reliable when estimating
the motor velocity with a low-resolution encoder. In this paper, we propose a fault detection method with sensorless estimation
using current ripples that estimates the position and velocity of the motor by detecting periodical oscillations of the armature
current caused by rotor slots. In addition, this method can estimate the position and velocity of the motor with less computational
effort than a state observer. Moreover, the method is less sensitive to motor parameters than model-based estimation methods.
The effectiveness of this method is validated with experimental data, and the simulation results show that various faults
have their own residual patterns. Therefore, we can detect the presence of faults by monitoring the residual signals. 相似文献
212.
This paper describes the on-line debugging software developed by our research team. The software has five functions and can be helpful in achieving rapid development for hybrid electric buses. In addition, the software can monitor system states continuously and also modify parametric maps or update control programs using its on-line programming function. Based on the on-line debugging system, the hybrid propulsion control system is designed, and all the working modes of the hybrid electric bus are tested. Finally, experiments are carried out that verify that the debugging system is feasible and reliable. The test results show that the hybrid electric bus can reduce fuel consumption by about 19.1 percent, in comparison with conventional buses. 相似文献
213.
J. Kim J. Kang Y. Kim T. Kim B. Min H. Kim 《International Journal of Automotive Technology》2010,11(4):565-571
The power split type hybrid system transmits engine power by dividing it into the electrical unit and the mechanical unit.
Its power transmission efficiency is highest at the mechanical point (MP), where the full power is transmitted to the mechanical
unit. In this study, the equation for the MP was derived for the gear ratios of a general 4-node lever model. The MP characteristics
for the transmission ratio (TR) of the input split and compound split structures were examined using the equation derived.
Using the examined input split and compound split structures, a systematic design method for the dual mode power split transmission
was proposed. In the dual mode power split transmission, the MP could be positioned at the desired TR, and the input split
and compound split modes could be selectively used according to the clutch combination, which leads to the operation of the
vehicle within a high system efficiency range. 相似文献
214.
We investigated the effects of injection parameters such as injection pressure, ambient pressure, and ambient temperature
on spray characteristics. We calculated the turbulence occurring point (t
c
), defined as the time required to generate a vortex, and the deceleration point (t
b
), defined as the time when spray penetration begins to decelerate, to elucidate the breakup mechanism of the test injectors.
The spray velocity coefficient (Cv) was obtained to evaluate the spray characteristics. As the ambient pressure increases in the case of a slit injector, Cv decreases. We investigated the effects of nozzle tip shape according to injection pressure, ambient pressure, and fuel properties
on spray characteristics and provide a Cv value of 0.38 for the swirl injector with a spray angle of 60° and the slit injector under atmospheric conditions. The value
of Cv in the case of a slit injector was reduced by increasing the ambient pressure. Our results suggest that Cv of a swirl injector is constant regardless of changes in ambient pressure, injection pressure, and fuel properties. On the
other hand, Cv of a slit injector is altered by changes in ambient pressure. 相似文献
215.
H. S. Seo B. C. Kim P. S. Park C. D. Lee S. S. Lee 《International Journal of Automotive Technology》2013,14(1):91-99
In this paper, we propose a universal plug and play (UPnP) — controller area network (CAN) gateway system using UPnP middleware for interoperability between external smart devices and an in-vehicle network. The proposed gateway consists of a UPnP communication device, a CAN communication device, and a device translator layer. In-vehicle devices are not usually IP-based, so we implemented an in-vehicle device manager in the UPnP communication device which is in the gateway. We developed a vehicle simulator to produce real vehicular data for performance analysis. The CAN communication device transmits and receives real-time vehicle data between the real vehicular simulator and external devices through the UPnP. The device translator layer configures a message frame for enabling seamless data input and output between the CAN and UPnP protocols. After implementation, we generated an internal-external service request and tested the result. Finally, we confirmed the service request and operation between external devices and the internal vehicular device. Additionally, for a variety of external device numbers and communication environments, we demonstrated the gateway performance by measuring the round trip time (RTT) for overall service implementation. 相似文献
216.
To simulate the hydroplaning of a tire, many analytical studies have been performed using commercial explicit FE (Finite Element) codes such as MSC.DYTRAN and LS-DYNA. However, most previous studies on this subject have addressed simulation of hydroplaning for water more than 5 mm deep. Additionally, because a great number of Eulerian elements and Lagrangian elements are typically used to analyze hydroplaning and because multiple analyses should be performed for various water depths, long CPU times are required. In this study, it was found that the traction force and the lift and drag forces between the tire and the road surface could be easily estimated for water shallower than 5 mm using an exponential function based on tire rolling FE simulation results. Furthermore, changes in skid resistance, expressed as SN (skid number), could be estimated for various water depths and vehicle speeds using the method proposed in this study, and the results were proven to be in good agreement with results obtained using the ASTM E274 Pavement Friction Tester. 相似文献
217.
218.
219.
Y. H. Ki K. J. Lee J. S. Cheon H. S. Ahn 《International Journal of Automotive Technology》2013,14(5):739-745
In this paper, an improved clamping force estimator is proposed for Electro-Mechanical Brake (EMB) systems by using the motor rotor position information and the hysteresis characteristics of mechanical parts in the EMB. A cascaded type of a force/position control system with a force sensor or an estimator was designed and implemented to control the clamping force and to keep the clearance gap in EMB systems. The EMB Hardware-In-the-Loop-Simulation (HILS) results show that the proposed force estimator yields better estimation performance than the existing estimator and that the clamping force control system based on the estimator can be also used for the fault tolerant control of the system. 相似文献
220.
Håkan T. Sandersen 《Coastal management》2013,41(5):447-463
This article discusses the impact of the Norwegian government's administrative reform on the management of the Norwegian aquaculture industry and coastal areas. The 2010 reform of government administration strengthened the County Councils’ role in issues of aquaculture at the expense of the regional offices of the Directorate of Fisheries. The aim of the reform was to increase self-governance through decentralization. However, international trends in coastal zone and marine resource management are moving in the opposite direction, aiming at more integrated and ecosystem-based approaches involving the management of larger, rather than smaller, geographic regions. This article examines the possible effects of this reform in light of the move from government to governance, and in the context of a broad policy shift toward a more integrated, ecosystem-based management (EBM) of the coastal zone. Based on insights from multi-level and coastal zone governance debates, we argue that an unintended consequence of the Norwegian administrative reform could be increased fragmentation of the aquaculture governance system, as well as a reduced capacity to implement EBM-related measures. At the same time, the reform might improve coastal zone planning, although a further step toward integrated coastal zone management (ICZM) would require a greater delegation of authority to the County Councils. 相似文献