Modeling of a Hybrid-Hydraulic Electric Vehicle

This paper introduces modeling of a gearless hydraulic transmission system that provides an infinite speed ratio like continuous variable transmission (CVT). The transmission system is modeled in various operating conditions such as all-electric and gasoline configurations. The results demonstrate the high performance operation of the transmission system.

Gear Based Quasi-Continuous Variable Transmission for Wind Turbines

Volume 6B: Energy ◽

10.1115/imece2015-50683 ◽

2015 ◽

Author(s):

Krista Hernandez ◽

Dania Wilson ◽

Kyle Ressel ◽

Justus Nwoke ◽

Martin Soto ◽

...

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Continuous Variable ◽

Transmission System ◽

Constant Speed ◽

Spur Gears ◽

Variable Speed ◽

Electrical Load ◽

Over the past decade wind turbines have been proven to be a competitive contender to produce cheap electricity. Their output electrical power went from few dozens of watts to several megawatts, and this trend is continuing to increase as they become larger in size. Most of these wind turbines are typically regulated through a set of controls acting on the electricity generator workload. These controls are achieved through the use of power electronics controlling the electrical load on the generator for variable speed wind turbine. This paper explores the possibility of implementing an alternative control system in variable wind speed turbines using a special gearbox with a high number of close consecutive discrete gear ratios. The proposed gear based Quasi-Continuous Variable Transmission, called QCVT, allows a variable speed at the input shaft and delivers a quasi-constant speed at the output shaft of the gearbox. The system consists of a special drivetrain assembly of spur gears run and controlled automatically through a set of clutch power shifters. The clutches are used to shift a set of compound gears, thus modifying the drivetrain total gear ratio. The designed system can produce up to 625 gear ratios and acts as a quasi-continuously variable transmission between the wind turbine hub and the electricity generator which requires a constant entry speed delivering a frequency of 60 Hz. The gearing transmission system has been designed using the SolidWorks CAD software for modeling and simulation and the gearing design theory has been used to dimension the special drivetrain assembly of spur gears. The kinematic gearing theory has been used to establish the multitude of close consecutive discrete gearing ratios of the transmission system. A wind driven rotor model for the wind turbine power coefficient has been used to determine the power absorbed by the wind turbine from the blowing wind and the power delivered to the electricity generator. The wind turbine torque generated by the wind and the torque produced at the electricity generator have also been determined using the multitude of gear ratios of the designed drivetrain. A new control law is established to keep the wind turbine generator running at a quasi-constant speed while producing maximum power. Considering the QCVT with its numerous close and consecutive gear ratios as the main torque regulator, the wind turbine system is expected to deliver the right needed torque for a specified electrical load. A set of results featuring how the electricity generator power and torque can be controlled by shifting the ratios of drivetrain transmissions are delivered. A particular emphasis is put on maximizing the generator delivered power using controlled gear ratios while the speed of the wind is changing. A small scale prototype of the QCVT powertrain transmission has been designed and built for concept demonstration and testing purposes.

An Experimental Study on Dynamics of a Novel Dual-Belt Continuous Variable Transmission Based on a Newly Developed Test Rig

Shock and Vibration ◽

10.1155/2015/857978 ◽

2015 ◽

Vol 2015 ◽

pp. 1-23 ◽

Cited By ~ 2

Author(s):

Pak Kin Wong ◽

Zhengchao Xie ◽

Yueqiao Chen

Keyword(s):

Experimental Study ◽

Analytical Model ◽

Continuous Variable ◽

Transmission Efficiency ◽

Speed Ratio ◽

Test Rig ◽

Light Load ◽

Continuously Variable Transmissions ◽

A novel dual-belt Van Doorne’s continuous variable transmission (DBVCVT) system, which is applicable to heavy-duty vehicles, has been previously proposed by the authors in order to improve the low torque capacity of traditional single-belt CVT. This DBVCVT is a novel design among continuously variable transmissions and is necessary to be prototyped for experimental study, and the analytical dynamic model for this DBVCVT also needs to be experimentally validated. So, this work originally fabricated a prototype of DBVCVT and integrates this prototype to a light-load hardware-in-the-loop test rig by replacing the engine and load equipment with the AC motor and magnetic powder dynamometer. Moreover, with the use of this newly developed test rig, this work implements the experimental study of this DBVCVT for the first time. The comparison of experimental and simulation results validates the previously proposed analytical model for DBVCVT, and some basic characteristics of the DBVCVT in terms of the reliability, speed ratio, and transmission efficiency are also experimentally studied. In all, this developed test rig with the analytical model lays the foundation for further study on this novel DBVCVT.

On the efficiency of a prototype continuous variable transmission system

21st Mediterranean Conference on Control and Automation ◽

10.1109/med.2013.6608736 ◽

2013 ◽

Cited By ~ 4

Author(s):

P. Spanoudakis ◽

N. C. Tsourveloudis

Keyword(s):

Continuous Variable ◽

Transmission System ◽

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

A new continuously variable transmission system applied to transmission system of the roadheader's cutting unit

10.1177/0954406216649404 ◽

2016 ◽

Vol 231 (19) ◽

pp. 3590-3600 ◽

Cited By ~ 14

Author(s):

Huan Wang ◽

Dongye Sun ◽

Datong Qin

Keyword(s):

Pulse Signal ◽

High Strength ◽

Basic Structure ◽

Continuous Variable ◽

Transmission System ◽

Speed Ratio ◽

Variable Transmission ◽

Strength Rock ◽

The Impact ◽

Cutting Unit

For the existing roadheader, the transmission system of the cutting unit cannot regulate speed and the cutting motor may break down because of the impact vibration. In this study, the power reflux hydraulic transmission system, which is a new continuous variable transmission system, is put forward to ameliorate these problems. The basic characteristics such as the speed ratio, efficiency and torque ratio are analysed on the basis of expounding the basic structure and operational principle of the power reflux hydraulic transmission system. The dynamic model of the transmission system of the cutting unit is established. The pulse signal is used as the simulation of the loads, when the roadheader suddenly encounters the high strength rock. Then the torsional vibration characteristics of the existing roadheader and the roadheader that is equipped with the power reflux hydraulic transmission system are analysed. The contrastive simulation results show that the motor and transmission system vibration of the roadheader which is equipped with the power reflux hydraulic transmission system is markedly attenuated relative to the existing roadheader. So the power reflux hydraulic transmission system can protect the cutting unit's motor and the transmission system.

Continuous Variable Transmission With an Inertia-Regulating System

Journal of Mechanical Design ◽

10.1115/1.4001378 ◽

2010 ◽

Vol 132 (5) ◽

Cited By ~ 5

Author(s):

G. Centeno ◽

F. Morales ◽

F. B. Perez ◽

F. G. Benitez

Keyword(s):

Angular Velocity ◽

Power Transmission ◽

Continuous Variable ◽

Transmission System ◽

Computational Simulations ◽

Efficient Manner ◽

Additional Degree ◽

System A ◽

This article describes a power transmission system applicable to vehicles. It consists of an oscillating, ratcheting-type, continuously variable transmission (CVT) system governed by an inertia mechanism. The inertia-regulating mechanism adds an additional degree of freedom and gives the system a dynamic character. The transmission consists of three different subsystems. The first of these converts the rotation of the engine or motor into an oscillating angular velocity movement and regulates the amplitude of this movement. The oscillating rotation from the first subsystem is used to drive a second subsystem, which acts as a regulating device by means of an inertial mechanism. The oscillating movement at the output of the second subsystem is rectified in the third, resulting in a unidirectional angular velocity. As a result, a unidirectional torque is generated at the output of the CVT, commensurate with the operating condition of the transmission, and this is capable of overcoming a torque resistance. A prototype of this transmission was built and tested to check the experimental results against those predicted by a series of computational simulations. As a result, the experimental graphs that characterize the operation of this type of transmission system were obtained, demonstrating its ability to function in an efficient manner.

A nano continuous variable transmission system from nanotubes

Nanotechnology ◽

10.1088/1361-6528/aaa286 ◽

2018 ◽

Vol 29 (7) ◽

pp. 075707

Author(s):

Kun Cai ◽

Jiao Shi ◽

Yi Min Xie ◽

Qing H Qin

Keyword(s):

Continuous Variable ◽

Transmission System ◽

Research on HMCVT Efficiency Model Based on the Improved SA Algorithm

Mathematical Problems in Engineering ◽

10.1155/2019/2856908 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Zhun Cheng ◽

Zhixiong Lu ◽

Fang Dai

Keyword(s):

Control Strategies ◽

Continuous Variable ◽

Transmission Efficiency ◽

Calculation Model ◽

Operating Conditions ◽

Hydraulic Systems ◽

Total Transmission ◽

Model Research ◽

Research on the efficiency characteristic of the hydromechanical continuous variable transmission (HMCVT) in tractors is key to obtaining optimal transmission, developing control strategies, and assessing efficiency. To ease and improve the accuracy of obtaining the efficiency completely based on test measurements or theoretical calculation, this study proposes a method for building the HMCVT efficiency model. The method is based on an improved simulated annealing (SA) algorithm according to a small amount of test data. The study uses 8 groups of transmission efficiency values under different operating conditions obtained from bench tests. By theoretical analysis of the HMCVT, this study divides the total transmission efficiency into (i) the transmission efficiency from the output power of the power source to the confluence mechanism, (ii) the transmission efficiency of the confluence mechanism, and (iii) the transmission efficiency of the output part after confluence. The formulas for the three parts of transmission efficiencies are then derived. This study improves the SA algorithm and uses it to identify the three key parameters of hydraulic systems of the transmission efficiency calculation model. Research results indicate that the efficiency model built using the proposed method exhibits high accuracy with an error of about 1.90%. The improved SA algorithm can rapidly complete key parameter identification with an error of about 2.16%; when the displacement ratio is 0, the efficiency values at the same stage are approximately equal under different operating conditions. The HMCVT efficiency model can be built rapidly and effectively with only five groups of efficiency measurement tests.