scholarly journals Components Sizing and Performance Analysis of Hydro-Mechanical Power Split Transmission Applied to a Wheel Loader

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1613 ◽  
Author(s):  
Shaoping Xiong ◽  
Gabriel Wilfong ◽  
John Lumkes
Keyword(s):  
Control System ◽  
Fuel Economy ◽  
Mechanical Power ◽  
Mechanical Transmission ◽  
Road Vehicles ◽  
Drive Cycle ◽  
Wheel Loader ◽  
Vehicle Velocity ◽  
Power Split ◽  
Wheel Loaders

The powertrain efficiency deeply affects the performance of off-road vehicles like wheel loaders in terms of fuel economy, load capability, smooth control, etc. The hydrostatic transmission (HST) systems have been widely adopted in off-road vehicles for providing large power density and continuous variable control, yet using relatively low efficiency hydraulic components. This paper presents a hydrostatic-mechanical power split transmission (PST) solution for a 10-ton wheel loader for improving the fuel economy of a wheel loader. A directly-engine-coupled HST solution for the same wheel loader is also presented for comparison. This work introduced a sizing approach for both PST and HST, which helps to make proper selections of key powertrain components. Furthermore, this work also presented a multi-domain modeling approach for the powertrain of a wheel loader, that integrates the modeling of internal combustion (IC) engine, hydraulic systems, mechanical transmission, vehicle(wheel) dynamics, and relevant control systems. In this modeling, an engine torque evaluation method with a throttle position control system was developed to describe the engine dynamics; a method to express the hydraulic loss of the axial piston hydraulic pump/motor was developed for modeling the hydraulic transmission; and a vehicle velocity control system was developed based on altering the displacement of a hydraulic unit. Two powertrain models were developed, respectively, for the PST and HST systems of a wheel loader using MATLAB/Simulink. The simulation on a predefined wheel loader drive cycle was conducted on both powertrain models to evaluate and compare the performance of wheel loader using different systems, including vehicle velocity, hydraulic displacement control, hydraulic torque, powertrain efficiency, and engine power consumption. The simulation results indicate that the vehicle velocity controller developed functions well for both the PST and HST systems; a wheel loader using the proposed PST solution can overall save about 8% energy consumption compared using an HST solution in one drive cycle. The sizing method and simulation models developed in this work should facilitate the development of the powertrains for wheel loaders and other wheeled heavy vehicles.

Investigation on the Energy Management Strategy for Hydraulic Hybrid Wheel Loaders

2013 ◽  
Author(s):  
Feng Wang ◽  
Mohd Azrin Mohd Zulkefli ◽  
Zongxuan Sun ◽  
Kim A. Stelson
Keyword(s):  
Energy Management ◽  
Hydraulic System ◽  
Management Strategy ◽  
Energy Management Strategy ◽  
Road Vehicles ◽  
Engine Operation ◽  
Wheel Loader ◽  
Hydraulic Hybrid ◽  
Power Split ◽  
Wheel Loaders

Energy management strategies for a hydraulic hybrid wheel loader are studied in this paper. The architecture of the hydraulic hybrid wheel loader is first presented and the differences of the powertrain and the energy management system between on-road vehicles and wheel loaders are identified. Unlike the on-road vehicles where the engine only powers the drivetrain, the engine in a wheel loader powers both the drivetrain and the working hydraulic system. In a non-hybrid wheel loader, the two sub-systems interfere with each other since they share the same engine shaft. By using a power split drivetrain, it not only allows for optimal engine operation and regenerative braking, but also eliminates interferences between driving and working functions, which improve the productivity, fuel efficiency and operability of the wheel loader. An energy management strategy (EMS) based on dynamic programming (DP) is designed to optimize the operation of both the power split drivetrain and the working hydraulic system. A short loading cycle is selected as the duty cycle. The EMS based on DP is compared with a rule-based strategy through simulation.

scholarly journals Loader power-split transmission system based on a planetary gear set

2018 ◽  
Vol 10 (1) ◽  
pp. 168781401774773 ◽  
Author(s):  
Chang Lyu ◽  
Zhao Yanqing ◽  
Lyu Meng
Keyword(s):  
Output Power ◽  
Fuel Economy ◽  
Power Transmission ◽  
Planetary Gear ◽  
Torque Converter ◽  
Transmission Efficiency ◽  
Transmission System ◽  
Mechanical Transmission ◽  
Power Split ◽  
Hydraulic Torque Converter

In hydraulic mechanical transmission loaders, a hydraulic torque converter can prevent an engine from stalling due to overloading of the loader during the spading process; however, the hydraulic torque converter also reduces the loader’s fuel economy because of its low transmission efficiency. To address this issue, the study designs an output-power-split transmission system that is applied to a hybrid loader. The designed transmission system removes the hydraulic torque converter in the power transmission system of a traditional loader and adopts a planetary gear set with a compact structure as the dynamic coupling element, thus allowing the output power of the loader to be split transmitted. During shoveling, the loader power-split transmission system based on a planetary gear set can prevent the motor from plugging and over-burning under conditions that ensure that the traction does not decrease. In addition, the transmission efficiency and loader fuel economy are higher in the proposed transmission system than in the power transmission system of a traditional loader. The test results show that the transmission efficiency of the designed system was 13.2% higher than that of the traditional hydraulic mechanical transmission loader.

Performance analysis of hydrodynamic mechanical power-split transmissions

2021 ◽  
pp. 095440702110339
Author(s):  
Xiaojun Liu ◽  
Dongye Sun ◽  
Junlong Liu
Keyword(s):  
Energy Savings ◽  
Performance Metrics ◽  
Mechanical Power ◽  
Speed Ratio ◽  
Vehicle Speed ◽  
Wheel Loader ◽  
Loading Cycle ◽  
Average Efficiency ◽  
Transmission Parameters ◽  
Power Split

The objective of this study was to evaluate the performance of 24 basic hydrodynamic mechanical power-split (HMPS) transmission designs effectively based on their torque multiplication capacities (TMCs) and efficiencies. Firstly, four schemes were preliminarily selected. Secondly, the matching between the four schemes and a reference wheel loader was considered, and an expression for the TMC was developed based on the traditional transmission and a second reference transmission. Thirdly, two performance metrics in terms of the TMC and efficiency – the average torque multiplication capacity (ATMC) and average efficiency – were defined to eliminate the couplings of four transmission parameters with the vehicle speed and speed ratio. Finally, the performances of the two best schemes and traditional hydrodynamic mechanical (HM) transmission were carefully compared. The results show that a transmission with power recirculation cannot present energy savings potential regardless of the ATMC, whereas a transmission with a power split can achieve an ATMC of 0.255, an average efficiency increment of 0.0143 in the short loading cycle, and a miniscule efficiency increment in the long loading cycle compared with the HM transmission.

Hydro-mechanical power split transmissions: Progress evolution and future trends

2018 ◽  
Vol 233 (3) ◽  
pp. 727-739 ◽  
Author(s):  
Jin Yu ◽  
Zhu Cao ◽  
Min Cheng ◽  
Rongzhao Pan
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Mechanical Power ◽  
Mechanical Transmission ◽  
Hydraulic Hybrid ◽  
The World ◽  
Power Split ◽  
Hybrid Transmission ◽  
Key Techniques ◽  
Important Form

The hydro-mechanical power split transmission is an important form of hydraulic hybrid transmission, combining the stepless speed characteristics of hydraulic transmission and the high efficiency of mechanical transmission. Recently, the hydro-mechanical power split transmission, with its relatively large potential for energy recovery and improving the environment, and its low cost, has attracted many scholars from all over the world. Because there are many types of hydro-mechanical power split transmission, the different forms are complex, and researchers across the world are relatively dispersed, it has experienced a long and arduous development process. Therefore, it is important to summarize the types, developments, and achievements of this transmission. From the recent literature at home and abroad, this paper summarizes developments, key techniques and trends, analyses problems and difficulties in design and application, discusses the methods for solving these problems, and provides references for the development and application of hydro-mechanical power split transmission.

Modeling and Simulation of a Vehicle Equipped with Power Split Automatic Transmission

2011 ◽  
Vol 383-390 ◽  
pp. 4708-4712
Author(s):  
Qing Yong Zhang
Keyword(s):  
Modeling And Simulation ◽  
Fuel Economy ◽  
Control Strategy ◽  
High Efficiency ◽  
Automatic Transmission ◽  
Simulation Software ◽  
Driving Cycle ◽  
Mechanical Transmission ◽  
Power Split ◽  
Vehicle Simulator

his paper is concerned with the fuel economy of a mini car with power split automatic transmission (PSAT) by means of simulation. Firstly, a PSAT prototype is developed featured with high efficiency by power split. Secondly, mathematic models of PSAT, based on the PSAT scheme and experiment on the prototype, is established and embedded into the simulation software NREL’s Advanced Vehicle Simulator (ADVISOR) to carry out the whole vehicle fuel economy simulation. Thirdly, fuel economy comparison between vehicle with PSAT and traditional mechanical transmission is present, after fuel economy simulation under different driving cycle. Finally, approach to the energy save scheme of PSAT and matching between PSAT and the whole vehicle is discussed which builds up a good foundation for future optimization on control strategy of PSAT.

Controls Development and Vehicle Drive Cycle Analysis of Integrated Turbocompounding, Electrification and Supercharging System (ITES)

2018 ◽  
Author(s):  
Satyum Joshi ◽  
Erik Koehler ◽  
Mufaddel Dahodwala ◽  
Michael Franke ◽  
Jeffrey D. Naber
Keyword(s):  
Fuel Economy ◽  
Control Strategy ◽  
Substantial Reduction ◽  
Development Effort ◽  
Drive Cycle ◽  
Engine Torque ◽  
Cycle Simulation ◽  
Battery Capacity ◽  
Power Split ◽  
Generator Unit

Integrated Turbocompounding, Electrification and Supercharging (ITES) is a novel approach for integrated implementation of technologies aimed at reduction of fuel consumption in a single unit. The ITES system optimally manages the power flow between the turbocompound turbine, secondary compressor, 48V electric motor/generator and engine by employing a planetary gear set. The unified approach delivers a substantial reduction in both expense and space claim while improving the overall system efficiency in comparison to the independent implementation of each of these individual technologies. As part of a previous development effort the ITES system functionality was validated through engine drive cycle simulation primarily utilizing the 48V motor generator unit for power split turbocompounding, power split supercharging and engine torque assist. In this latest development phase, the functionality of ITES system has been evaluated on a vehicle level model through a vehicle drive cycle simulation. First, a supervisory control strategy was developed for the ITES system to facilitate start-stop, regenerative braking and engine torque assist functionality using the ITES motor/generator unit. Next, a GT-Suite engine model developed for a downsized engine with the ITES unit applied, along with an appropriate control strategy, was integrated in to a class 6/7 vocational vehicle 1D model. The model was then simulated over the GHG Phase 2 ARB cycle and the fuel economy was compared to that of vehicle model with only the baseline engine configuration. Finally, the battery capacity was optimized to maximize vehicle fuel economy and battery life.

Multi-layer controller with state-constraint: Vehicle lateral stability control based on fuzzy logic

2021 ◽  
pp. 095440702110142
Author(s):  
Neng Wan ◽  
Guangping Zeng ◽  
Chunguang Zhang ◽  
Dingqi Pan ◽  
Songtao Cai
Keyword(s):  
Control System ◽  
Integrated Control ◽  
State Constraint ◽  
Stability Control ◽  
Lateral Stability ◽  
System A ◽  
Velocity Reduction ◽  
Vehicle Velocity ◽  
Allowable Range ◽  
Simulation Results

This paper deals with a new state-constrained control (SCC) system of vehicle, which includes a multi-layer controller, in order to ensure the vehicle’s lateral stability and steering performance under complex environment. In this system, a new constraint control strategy with input and state constraints is applied to calculate the steady-state yaw moment. It ensures the vehicle lateral stability by tracking the desired yaw rate value and limiting the allowable range of the side slip. Through the linkage of the three-layer controller, the tire load is optimized and achieve minimal vehicle velocity reduction. The seven-degree-of-freedom (7-DOF) simulation model was established and simulated in MATLAB to evaluate the effect of the proposed controller. Through the analysis of the simulation results, compared with the traditional ESC and integrated control, it not only solves the problem of obvious velocity reduction, but also solves the problem of high cost and high hardware requirements in integrated control. The simulation results show that designed control system has better performance of path tracking and driving state, which is closer to the desired value. Through hardware-in-the-loop (HIL) practical experiments in two typical driving conditions, the effectiveness of the above proposed control system is further verified, which can improve the lateral stability and maneuverability of the vehicle.

Optimization for speed regulation strategy of compound coupled hydro-mechanical transmission

2020 ◽  
pp. 095440702098056
Author(s):  
Jin Yu ◽  
Pengfei Shen ◽  
Zhao Wang ◽  
Yurun Song ◽  
Xiaohan Dong
Keyword(s):  
Fuel Consumption ◽  
Dynamic Programming Algorithm ◽  
Operating Conditions ◽  
Programming Algorithm ◽  
Speed Ratio ◽  
Mechanical Transmission ◽  
Speed Regulation ◽  
Ratio Change ◽  
Low Efficiency ◽  
Wheel Loaders

Heavy duty vehicles, especially special vehicles, including wheel loaders and sprinklers, generally work with drastic changes in load. With the usage of a conventional hydraulic mechanical transmission, they face with these problems such as low efficiency, high fuel consumption and so forth. Some scholars focus on the research to solve these issues. However, few of them take into optimal strategies the fluctuation of speed ratio change, which can also cause a lot of problems. In this study, a novel speed regulation is proposed which cannot only solve problems above but also overcome impact caused by speed ratio change. Initially, based on the former research of the Compound Coupled Hydro-mechanical Transmission (CCHMT), the basic characteristics of CCHMT are analyzed. Besides, to solve these problems, dynamic programming algorithm is utilized to formulate basic speed regulation strategy under specific operating condition. In order to reduce the problem caused by speed ratio change, a new optimization is applied. The results indicate that the proposed DP optimal speed regulation strategy has better performance on reducing fuel consumption by up to 1.16% and 6.66% in driving cycle JN1015 and in ECE R15 working condition individually, as well as smoothing the fluctuation of speed ratio by up to 12.65% and 19.01% in those two driving cycles respectively. The processes determining the speed regulation strategy can provide a new method to formulate the control strategies of CCHMT under different operating conditions particularlly under real-world conditions.

Sign in / Sign up

Export Citation Format

Share Document