Integrated control strategy of tractor hydromechanical continuously variable transmission

2020 ◽  
pp. 095440702095114
Author(s):  
Guang Xia ◽  
Huayu Zong ◽  
Xiwen Tang ◽  
Linfeng Zhao ◽  
Baoqun Sun
Keyword(s):  
Control Strategy ◽  
Integrated Control ◽  
Continuous Variable ◽  
Transmission Efficiency ◽  
Variable Speed ◽  
Speed Regulation ◽  
Continuous Variable Transmission ◽  
Variable Transmission ◽  
Working Resistance ◽  
Transmission Speed

Given the transmission efficiency fluctuation and response lag problem of hydromechanical continuous variable transmission combined with the complex and variable working environment of a tractor, an integrated control strategy of engine throttle compensation–hydromechanical continuous variable transmission speed regulation is adopted for dual-flow transmission control. On the basis of the estimation of working resistance, a fuzzy algorithm is used to design the throttle compensation law. Considering the maximum driving power of a tractor as the target of variable speed control, an hydromechanical continuous variable transmission efficiency model is established, and the control law of an hydromechanical continuous variable transmission displacement ratio with the maximum driving power of the tractor under any working condition is determined. On the basis of the wavelet neural network proportional–integral–derivative algorithm, the control law of the hydromechanical continuous variable transmission speed regulation is designed, and the parameters of proportional–integral–derivative control are corrected in real time during the control process. Based on MATLAB/Simulink modelling and simulation and the real vehicle verification test, results showed that the influence of hydromechanical continuous variable transmission efficiency fluctuation on the driving power of the entire vehicle, the response lag of the pump-controlled motor system, and the effect of the leakage on the variable speed control and the fluctuation of the working resistance are solved by studying the hydromechanical continuous variable transmission variable speed transmission control strategy. This strategy improves the stability of the tractor speed and ensured the quality of the work, thereby improving the ability of the tractor to adapt to complex working environments.

Gear Based Quasi-Continuous Variable Transmission for Wind Turbines

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 ◽  
Continuous Variable Transmission ◽  
Variable Transmission

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.

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

2015 ◽  
Vol 2015 ◽  
pp. 1-23 ◽  
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 ◽  
Continuous Variable Transmission ◽  
Continuously Variable Transmissions ◽  
Variable Transmission

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.

scholarly journals Research on HMCVT Efficiency Model Based on the Improved SA Algorithm

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
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 ◽  
Continuous Variable Transmission ◽  
Variable Transmission

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.

Characteristics of the Hydro-Mechanical Continuously Variable Transmission in the Wheeled Tractor

2014 ◽  
Vol 494-495 ◽  
pp. 167-170 ◽  
Author(s):  
Ming Zhu Zhang ◽  
Rui Guo ◽  
Chen Chen
Keyword(s):  
Power Flow ◽  
High Efficiency ◽  
Continuous Variable ◽  
Transmission Efficiency ◽  
Continuously Variable Transmission ◽  
Entire System ◽  
Continuous Variable Transmission ◽  
Variable Transmission

Based on the hydro-mechanical continuous variable transmission (HMCVT) of 400 house-power of Dongfanghong, the synchronization in period of contions to content to multiple period of HMCVT was established by analyzing its transmission principle, and the relation fomulas of power distributing ratio and efficiency was presented. That results showed that the characteristics of power flow at the first half and at the second half were different, when it was within the certain grade to do the boundary of e equaled with zero; while it was each grade in section points, that characters were the same; the more grades, the greater HMCVT system transmitting power and the higher the transmission efficiency of the entire system. The high efficiency features of multiple range hydro-mechanical stepless transmission, meet the requirement of tractor operation.

Support vector regression methodology for wind turbine reaction torque prediction with power-split hydrostatic continuous variable transmission

Energy ◽  
2014 ◽  
Vol 67 ◽  
pp. 623-630 ◽  
Author(s):  
Shahaboddin Shamshirband ◽  
Dalibor Petković ◽  
Amineh Amini ◽  
Nor Badrul Anuar ◽  
Vlastimir Nikolić ◽  
...  
Keyword(s):  
Wind Turbine ◽  
Support Vector Regression ◽  
Continuous Variable ◽  
Support Vector ◽  
Continuous Variable Transmission ◽  
Power Split ◽  
Variable Transmission ◽  
Reaction Torque

Optimum Design of the Continuously Variable Transmission for a Motorcycle

2001 ◽  
Author(s):  
Yuan Mao Huang ◽  
Bi Shyang Hu
Keyword(s):  
Simulated Annealing Algorithm ◽  
Continuous Variable ◽  
Design Parameters ◽  
Objective Functions ◽  
Design Variables ◽  
Continuous Variable Transmission ◽  
Product Method ◽  
Variable Transmission ◽  
Annealing Algorithm ◽  
Further Development

Abstract Many design parameters affect the performance of continuous variable transmissions. This paper presents the optimization of a continuous variable transmission by using the simulated annealing algorithm. The Bessel method of curve fitting and the tensor product method of surface fitting were used to facilitate the discrete fuel consumption, emissions of carbon monoxide (CO) and HC compound of experimental engine data. A compromise method was used to analyze the multi-objective functions. The values for design variables are recommended for further development.

scholarly journals Research on Transmission Characteristics of Hydromechanical Continuously Variable Transmission of Tractor

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Junyan Wang ◽  
Changgao Xia ◽  
Xin Fan ◽  
Junyu Cai
Keyword(s):  
Power Flow ◽  
Flow Direction ◽  
Transmission Efficiency ◽  
Continuously Variable Transmission ◽  
Simulation Software ◽  
Transmission Scheme ◽  
Compact Structure ◽  
Theoretical Derivation ◽  
Speed Regulation ◽  
Variable Transmission

This paper proposes a new transmission scheme of hydromechanical continuously variable transmission (HMCVT) for tractors. The HMCVT has 4 working ranges in each of the front and rear directions. The speed characteristic and the torque characteristic of HMCVT are theoretically derived. On the basis of HMCVT power flow direction, the Крейнeс formula is used to calculate the transmission efficiency. Then, the image analysis method is used to study the influence of parameters on the transmission efficiency of HMCVT, and the main influencing factors are found. The results of theoretical derivation demonstrate that, by coordinating control of the HST displacement ratio and the engagement conditions of shifting clutches, the stepless speed regulation of HMCVT at the tractor speed of 0–50 km/h can be realized. The proposed HMCVT has the ability to continuously transmit and change torque over all working ranges. The overall transmission efficiency of HMCVT is at a high level. To verify the theoretical derivation, Amesim simulation software is used for the modeling and simulation of HMCVT. The simulation results are consistent with the theoretical analysis results. Therefore, the HMCVT proposed in this paper has the advantages of compact structure and high transmission efficiency, and it is suitable for matching tractors.

Sign in / Sign up

Export Citation Format

Share Document