A Magnetorheological Mount for Hydraulic Hybrid Vehicles

2009 ◽  
Author(s):  
The Nguyen ◽  
Mohammad Elahinia ◽  
Constantin Ciocanel
Keyword(s):  
Fuel Efficiency ◽  
Wide Frequency Range ◽  
Hybrid Vehicles ◽  
Working Fluid ◽  
Frequency Range ◽  
Isolation System ◽  
Power Sources ◽  
Hydraulic Hybrid ◽  
Operating Frequency Range ◽  
Stiffness And Damping

Advanced vehicular technologies have been increasingly popular since they improve fuel economy. Automobiles with variable cylinder management are capable of turning on/off the cylinders in order to optimize the fuel consumption. Hybrid vehicles such as hybrid electric vehicles (HEVs) or hydraulic hybrid vehicles (HHVs) allow the engines to operate in the most efficient region. Besides, the hybrid technology includes capturing the braking energy, otherwise wasted as heat, to aid the acceleration. However, the enhancement in fuel efficiency comes with unbalance, shock and wider range of frequency vibration. Noise and vibration is actually one of the main obstacles in commercializing the HHV technology. This study is to design a vibration isolator to work for HHVs effectively and economically. The vibration profile of HHVs is proven to include both shock load at the switches of power sources and wide frequency range of vibration. That the HHV’s engine is turned on/off frequently and the hydraulic pumps/motors operate between 0 and 2000RPM, corresponding to 0–300Hz, poses difficult challenges for the isolation system. Rubber mounts are cheap, but only good for static load support and suitable for low power engine. Passive hydraulic mounts are only effective for conventional engines with unvarying working schedules. On the other hand, the active mounts are responsive for any condition, but too costly for commercial vehicles. Semi-active mounts with magnetorheological fluid (MRF) have been researched and recognized as a highly potential solution for hydraulic hybrid vehicles. The semi-active MRF mount is constructed very similar to a conventional hydraulic mount. However, the working fluid is an MRF which can quickly change its characteristics when the magnetic field is present. The main features of the MRF mount include multiple controllable MR valves, utilizing the flow (valve) mode, to connect the top and bottom fluid chambers. In addition, the mount is also capable of employing the fluid in squeeze mode. The structure of the MRF mount allows the stiffness and damping to be controlled in real time. The controllability makes the mount tunable to particularly fit the requirements of the HHVs. In this study, a mathematical model was constructed to predict the performance of the mount. The parameters were tuned so that the mount is effective within the whole operating frequency range of the HHV’s vibration.

scholarly journals Vibration Isolation for Parallel Hydraulic Hybrid Vehicles

2008 ◽  
Vol 15 (2) ◽  
pp. 193-204 ◽  
Author(s):  
The M. Nguyen ◽  
Mohammad H. Elahinia
Keyword(s):  
Vibration Isolation ◽  
Fuel Efficiency ◽  
Hybrid Vehicles ◽  
Vehicle Body ◽  
Hydraulic Systems ◽  
Isolation System ◽  
Noise And Vibration ◽  
Hydraulic Hybrid ◽  
Heavy Duty Vehicle ◽  
Vibration Transmissibility

In recent decades, several types of hybrid vehicles have been developed in order to improve the fuel economy and to reduce the pollution. Hybrid electric vehicles (HEV) have shown a significant improvement in fuel efficiency for small and medium-sized passenger vehicles and SUVs. HEV has several limitations when applied to heavy vehicles; one is that larger vehicles demand more power, which requires significantly larger battery capacities. As an alternative solution, hydraulic hybrid technology has been found effective for heavy duty vehicle because of its high power density. The mechanical batteries used in hydraulic hybrid vehicles (HHV) can be charged and discharged remarkably faster than chemical batteries. This feature is essential for heavy vehicle hybridization. One of the main problems that should be solved for the successful commercialization of HHV is the excessive noise and vibration involving with the hydraulic systems. This study focuses on using magnetorheological (MR) technology to reduce the noise and vibration transmissibility from the hydraulic system to the vehicle body. In order to study the noise and vibration of HHV, a hydraulic hybrid subsystem in parallel design is analyzed. This research shows that the MR elements play an important role in reducing the transmitted noise and vibration to the vehicle body. Additionally, locations and orientations of the isolation system also affect the efficiency of the noise and vibration mitigation. In simulations, a skyhook control algorithm is used to achieve the highest possible effectiveness of the MR isolation system.

A Magnetorheological Vibration Isolator for Hydraulic Hybrid Vehicles

2005 ◽  
Author(s):  
The M. Nguyen ◽  
Mohammad H. Elahinia
Keyword(s):  
Vibration Isolation ◽  
Fuel Efficiency ◽  
Mr Damper ◽  
Hybrid Vehicles ◽  
Noise And Vibration ◽  
Variable Yield ◽  
Carrier Fluid ◽  
Mr Dampers ◽  
Hydraulic Hybrid ◽  
Motor Component

This paper presents the results of vibration isolation analysis for the pump/motor component of hydraulic hybrid vehicles (HHV). The hybrid subsystem can potentially improve the fuel efficiency of the vehicle by recovering some of the energy that is otherwise wasted in friction brakes. High pressure hydraulic fluid “assists” the engine in the initial acceleration period. Noise and vibration are an issue with these systems due to the variable hydraulic loads that are applied to the regenerative hybrid element. This study looks into the possibility of reducing the transmitted noise and vibration to the vehicle’s chassis by using smart magnetorheological (MR) dampers. MR dampers utilize MR fluid which is made of pure iron particles suspended in a carrier fluid. MR fluids deliver variable yield stress under the effect of a controllable electromagnetic field. To this end, an MR damper is modeled and simulated. In the simulation both shock and vibration loads are considered. The simulation results are compared with the performance of regular elastomer isolators. It is shown that the MR damper can effectively reduce the vibration for different working cycles of the regenerative system.

scholarly journals SIGNIFICANCE OF USING HYDRAULIC OIL AS WORKING FLUID IN HYDRAULIC HYBRID VEHICLES

2019 ◽  
Vol 04 (04) ◽  
pp. 115-118
Author(s):  
Chada Jithendra Sai Raja ◽  
Mahboob Shaheen ◽  
Dwarampudi Ramya Sudha ◽  
Vankala Nagababu
Keyword(s):  
Hybrid Vehicles ◽  
Working Fluid ◽  
Hydraulic Oil ◽  
Hydraulic Hybrid

A 6-DOF vibration isolation system for hydraulic hybrid vehicles

2006 ◽  
Author(s):  
The Nguyen ◽  
Mohammad Elahinia ◽  
Walter W. Olson ◽  
Paul Fontaine
Keyword(s):  
Vibration Isolation ◽  
Hybrid Vehicles ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Hydraulic Hybrid

A Study of Fluid Squeeze-Film Damping

1966 ◽  
Vol 88 (2) ◽  
pp. 451-456 ◽  
Author(s):  
W. S. Griffin ◽  
H. H. Richardson ◽  
S. Yamanami
Keyword(s):  
Wide Frequency Range ◽  
Squeeze Film ◽  
Experimental Program ◽  
Working Fluid ◽  
Viscous Damping ◽  
Extreme Temperatures ◽  
Frequency Range ◽  
Approximate Design ◽  
Squeeze Film Damping ◽  
Intense Radiation

The fluid squeeze-film produced by relative axial or tilting motion of two closely spaced plates provides viscous damping action over certain ranges of operation. When gas is the working fluid, a damper can be realized which is operable over a wide frequency range in the presence of extreme temperatures and intense radiation. A linearized analysis and approximate design equations, verified by a limited experimental program, are presented for several useful damper configurations.

scholarly journals Linear Ultrasound Transmitter Based on Transformer with Improved Saturation Performance

Electronics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 107
Author(s):  
Stefano Ricci ◽  
Dario Russo
Keyword(s):  
High Voltage ◽  
Magnetic Core ◽  
Wide Frequency Range ◽  
Portable Devices ◽  
Power Network ◽  
Frequency Range ◽  
Power Sources ◽  
Ultrasound Waves ◽  
Test Board ◽  
Wide Range

Ultrasound methods are currently employed in a wide range of applications. They are integrated in complex electronics systems, like clinical echographs, but also in small and compact boards, like industrial sensors, embedded systems, and portable devices. Ultrasound waves are typically generated by energizing a piezoelectric transducer through a high-voltage sequence of small sinusoidal bursts. Moreover, in several applications, the ultrasound board should work in a wide frequency range. This makes the transmitter, i.e., the electronics that drives the transducer, a key part of the circuit. The use of a small transformer simplifies the electronics and reduces the need of high-voltage power sources. Unfortunately, the transformer magnetic core, when subjected to the sequence of bursts employed in ultrasound, is particularly prone to saturation. This phenomenon limits the maximum voltage and/or the minimum frequency the transformer can be employed for. In this work, a transmitter based on a transformer is proposed. Inspired by the technique currently employed in the power network transformers, we added a prefluxing circuit, which improves the saturation performance 2-fold. The proposed transmitter was implemented in a test board and experimented with two commercial transformers at 80 Vpp. Measurements show that the proposed prefluxing circuit moves down the minimum usable frequency 2-fold: from 400 to 200 kHz for one of the two transformers, and from 2.4 to 1.2 MHz for the other.

Vibration Isolation Control for Hydraulic Hybrid Vehicles

2006 ◽  
Author(s):  
The M. Nguyen ◽  
Mohammad M. Elahinia
Keyword(s):  
Hydraulic System ◽  
Vibration Isolation ◽  
Fuel Efficiency ◽  
Gas Production ◽  
Hybrid Vehicles ◽  
Vehicle Body ◽  
Effective Control ◽  
Noise And Vibration ◽  
Hybrid Technology ◽  
Hydraulic Hybrid

In recent decades, many types of hybrid vehicles have been developed to compensate for the limited sources of oil and gas production. Gasoline-electric hybrid technology shows a significant improvement in fuel efficiency for small and medium-sized passenger vehicles. However, that hybrid type is not economically beneficial for larger vehicles due to large, harmful and expensive battery packs. Hydraulic hybrid technology has been found effective for heavy duty vehicle because of its high power density. Other advantages of hydraulic hybrid are the lower cost and environmental friendliness over the electric batteries. The potential achievement in fuel efficiency has been proved in several studies and experiments by different schools, institutes and laboratories. The only problems preventing this hydraulic hybrid technology going to the market are noise and vibration involving with the hydraulic system. This study focuses on using magnetorheological (MR) technology to reduce the noise and vibration transmissibility from the hydraulic system to the vehicle body. MR technology has been well-known with automotive applications such as engine mounts, vehicle's main suspension system. In order to study the nature of the problem, structure of a hydraulic hybrid vehicle in series design is analyzed. The operational characteristics of the powertrain are carefully studied, and the vibration data is formulated. This research shows that not only MR elements play an important role in vibration suppression, but also the geometrical configurations of the mounting systems affect the efficiency in noise and vibration isolation. To this end, simulation results are also used to determine the most effective control method for the MR mounts.

Vibration Mitigation With a Multi-Axial Magnetorheological Mount

2009 ◽  
Author(s):  
Walter Anderson ◽  
The Nguyen ◽  
Mohammad Elahinia
Keyword(s):  
Frequency Response ◽  
High Frequency ◽  
Low Frequency ◽  
Hybrid Vehicles ◽  
Experimental Results ◽  
Small Displacement ◽  
Frequency Range ◽  
Mr Fluid ◽  
High Frequency Response ◽  
Hydraulic Hybrid

This paper presents a multi-axial magnetorheological (MMR) mount. An MMR mount has been developed for use with hydraulic hybrid vehicles (HHV). Like hybrid electric vehicles (HEV), HHV provides better fuel economy. An inherent problem to hydraulic hybrid vehicles is vibration of the hydraulic pump-motor (P/M). This vibration can be classified as shock loading for initial start-up, and periodic vibration over a large frequency range. The latter vibration opportunity can be classified as having large displacement at low frequency and small displacement at high frequency. This requires a stiff mount for the low frequency response and a soft mount for the high frequency response. A single axis magnetorheological (MR) mount has previously been developed and studied by the same group. This was done to develop an understanding of the MR fluid and to discover the limitations of such a mount. Models to predict the experimental results have also been generated. These models show a good correlation to the experimental results. Then, the model has been enhanced from the single axis mount to a multi-axial. This was done by examining the 3-D CAD model to develop the different boundary conditions for the simulation. With a multi-axial magnetorheological mount, damping and stiffness can be altered to yield acceptable transmissibility over the frequency range. This is achieved through the use of an inertia track paired with a pseudo-decoupler. These features are commonly found in a passive hydraulic mount; however through the use of MR fluid, the downfalls of the hydraulic mount can be mitigated, e.g. performance deterioration outside of notch frequency. Additionally, a magnetorheological mount is semi-active so there is an inherent stability to the mount. The MMR mount uses elastomer and MR fluid to achieve the static stiffness to support the P/M and achieve low dynamic stiffness for the high frequency response, which is necessary for a good isolator. The advantages of the use of a multi-axial magnetorheological mount are as follows: fewer mounts are required, stability when compared to an active mount, less power required when compared to an active mount, better isolation when compared to pure elastomeric and passive hydraulic mounts. A model for a multi-axial magnetorheological mount has been developed and simulated. For the purposes of this study, elastomer has been considered to have a linear dynamic response. Additionally, the shock response of the mount has not been considered. Future work includes manufacturing a multi-axial MR mount to verify the simulation results.

scholarly journals System Characteristics Analysis for Energy Management of Power-Split Hydraulic Hybrids

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1837
Author(s):  
Hyukjoon Kwon ◽  
Monika Ivantysynova
Keyword(s):  
Power Systems ◽  
Energy Saving ◽  
Thermal Management ◽  
Fuel Efficiency ◽  
Hybrid Vehicles ◽  
Control Logic ◽  
Hydraulic Hybrid ◽  
Hybrid Powertrains ◽  
Power Split ◽  
System Temperature

Hydraulic hybrid powertrains provide an opportunity for specific applications, such as heavy-duty vehicles based on high-power density, which has not been included in other types of hybrid powertrains. Among the various architectures of hybrid vehicles, power-split hybrids have a greater possibility of producing better fuel efficiency than other hybrid architectures. This study analyzed the possible energy-saving characteristics of power-split hydraulic hybrid vehicles (HHVs); this has not been comprehensively described in previous studies. A typical configuration of power-split HHVs was modeled with the FTP-72 driving cycle using a novel simulation method that considered the dynamic and thermal behaviors together. The characteristics were analyzed in comparison to a power-split hydrostatic transmission (HST), which is designed with the same conditions except for hydraulic energy storage. The power-split HHV not only has a better fuel efficiency, but it also shows system energy-saving characteristics. The power-split HHV has more chances for engine idling, which is directly related to fuel consumption savings due to engine stop. Additionally, more engine idling time enables the system to operate in a more efficient area on the engine map by load leveling. The results for the system temperature show that the power-split HHV offers the possibility to deliver better thermal management because it prevents the waste of braking power, which is especially crucial for hydraulic systems in comparison to other power systems such as electric or mechanical power systems. The ease of thermal management results in less energy consumption for cooling down the system temperature by minimizing the cooling system, as well as in a better thermal stability for the hydraulic system. The power-split HHV characteristics analyzed in this study can be used to design and organize the system control logic while developing power-split HHVs.

scholarly journals MR- and ER-Based Semiactive Engine Mounts: A Review

2013 ◽  
Vol 2013 ◽  
pp. 1-21 ◽  
Author(s):  
Mohammad Elahinia ◽  
Constantin Ciocanel ◽  
The M. Nguyen ◽  
Shuo Wang
Keyword(s):  
Combustion Engine ◽  
Fuel Efficiency ◽  
Power Sources ◽  
Hybrid Propulsion ◽  
Vibration Isolators ◽  
Engine Mounts ◽  
Hydraulic Hybrid ◽  
Wide Range ◽  
Multiple Power ◽  
Noise Vibration

Hybrid propulsion technologies, including hybrid electric and hydraulic hybrid, equip vehicles with nonconventional power sources (in addition to the internal combustion engine) to provide higher fuel efficiency. However, these technologies tend to lead to higher levels of noise, vibration, and harshness in the vehicles, mainly due to the switching between the multiple power sources involved. In addition, the shocks and vibrations associated with the power sources switching may occur over a wide range of frequencies. It has been proven that passive vibration isolators (e.g., elastomeric and hydraulic mounts) are unable to mitigate or totally isolate such shocks and vibrations. Active mounts, while effective, are more complex, require significant power to operate, and can lead to system instabilities. Semiactive vibration isolators have been shown to be as effective as active mounts while being less complex and requiring less power to operate. This paper presents a review of novel semiactive shock and vibration isolators developed using magnetorheological and electrorheological fluids. These fluids change their yield stress in response to an externally applied magnetic and electric field, respectively. As a result, these fluids allow one to transform a passive hydraulic vibration isolator into a semiactive device.

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