International Journal of Powertrains (16 papers in press)

Regular Issues

• Robust Sliding Mode Hybrid Controller Applied to a Wind Energy Conversion System Based on a Doubly-Fed Induction Generator to Overcome Mechanical Parameters Uncertainties  
  by Nabil Dahri, OUASSAID Mohammed, Driss Yousfi 
  Abstract: The maximisation of the power production in a wind energy conversion system (WECS) based on a doubly-fed induction generator (DFIG) needs the control of the angular speed of the wind turbine. However, the different uncertainties that affect the estimation of the mechanical parameters of the WECS are a major problem faced by the speed controlling task. In this paper, a sliding mode hybrid controller (SMHC) is developed. The proposed controller ensures finite-time and fast convergence to steady-state, accurate tracking of the optimal angular speed, higher robustness against mechanical parameters uncertainties, and reduced overshoots in case of a sudden change in the wind velocity. A comparative study of the proposed controller’s performances with the fuzzy hybrid controller (FHC) and the classical PI controller is conducted in different mechanical parameters uncertainties and varying wind conditions. Simulation results prove the efficiency of the SMHC compared to the FHC and the PI controller.
  Keywords: sliding mode hybrid controller; wind energy conversion system; WECS; doubly-fed inductance generator; DFIG; mechanical parameters uncertainties; fuzzy hybrid controller.
  DOI: 10.1504/IJPT.2023.10048847
   
  
• The Hydrogen Combustion Engine for CO2 Neutral Goods Transport  
  by Mirko Plettenberg, Bernhard Raser, Martin Wieser, Damian Bloomfield, Allen Rajagopal 
  Abstract: The Green Deal of EU requires a mandatory CO2-reduction target for heavy commercial vehicles of 15 % in 2025 respectively 30 % in 2030. Technologies and solutions, which allow a robust target achievement in a technological and timely manner are needed. The required technology mix will comprise of fuel consumption reduction on existing powertrain concepts and certain shares of CO2-neutral energy carriers. These will contain direct usage of electricity and hydrogen as energy carrier. Hydrogen internal combustion engines offer, compared to fuel cells, advantages regarding maintaining the value creation chain and protecting powertrain and vehicle related investments in production facilities. Hydrogen engine concepts of the past show weaknesses in view of performance, dynamic and fuel consumption. This paper demonstrates necessary steps to overcome these weaknesses and establish hydrogen internal combustion engines as a short-term available CO2-neutral powertrain technology for heavy-duty commercial vehicles and illustrates the potential of this powertrain concept.
  Keywords: CO2 Reduction; Hydrogen Engine; Heavy-Duty Commercial Vehicles; Combustion & Mechanical Development; DVP; Reliability.
  
  
• Coordination Control for Output Voltage of Optical-storage Independent Microgrid based on Adaptive Optimization  
  by Haocheng Zhou, Fengting Lu, Youchun Liu 
  Abstract: The optical-storage independent microgrid system has complex structure, and the change of load parameters will lead to insufficient stability of output voltage. Therefore, a coordination control method for output voltage of optical-storage independent microgrid based on adaptive optimisation is proposed. The topological graph of optical-storage independent microgrid is constructed to obtain the load state parameters of optical-storage independent microgrid for constructing the optimisation model of load state parameters. Through adaptive adjustment of step and square wave response, the load state optimisation parameters are obtained by fusion processing, and then the output voltage of the optical-storage independent microgrid is constrained. The output voltage stability of optical-storage independent microgrid is adjusted, and the coordination control of output voltage stability of optical-storage independent microgrid is realised. The simulation results show that the optical-storage independent microgrid controlled by this method has good output voltage stability and strong adaptive parameter optimisation ability.
  Keywords: microgrid; output voltage; adaptive control; coordination control; load parameters; step response.
  DOI: 10.1504/IJPT.2023.10051099
   
  
• Mechanical simulation of a gear transmission with a thin-walled hollow shaft  
  by Zhaksylyk Galym, Hamza Bin Tariq, Christos Spitas 
  Abstract: This study presents a finite element-based analysis of the compliance, contact stress distribution and dynamical response of a gear transmission, where the typically rigid shaft of the large gear is replaced by a thin-walled hollow shaft equivalent. Quasi-static analysis is used for the compliance and stress calculation and eigenfrequency analysis is used to determine the dependency of eigenfrequencies and related eigenmodes on the hollow shaft thickness.
  Keywords: Solid shaft; thin-walled hollow shaft; compliance; transmission error; eigenfrequency.
  
  
• Simulation of Air Foil Bearings for Use in Turbo Compressor Applications  
  by William Heaps, Harry Questa, Mahdi MohammadPour, Stephen Bewsher, Guenter Offner 
  Abstract: This paper explores the use of air foil bearings (AFBs) in turbo compressor applications. AFBs are characterized by their high speed and clean operation exhibiting low mechanical losses and presenting the potential use in hydrogen fuel cell applications, as the problem of membrane poisoning is avoided. A novel explicit co-simulation methodology for analyzing the dynamic performance of a turbocharger using AFBs is presented. Using bearing maps defining colinear stiffness and damping, an adaptable tool is created through a mathematical bearing model explicitly coupled with a flexible multibody dynamic system. This system level model considers flexibility of the bodies contained, as well as a Coulomb damping mechanism provided by the sub-foil structure in the AFBs. The resonance of the system was observed around 70krpm with non-linear and sub synchronous vibrations also being experienced. Although computationally intensive, significantly more modes of vibration were detected when compared to rigid body analysis.
  Keywords: Air Foil Bearings; Engineering Simulation; Multibody Dynamics; Rotordynamics; Turbocharger.
  
  
• Influence of position error of planetary gear on the vibrations of planetary gear system  
  by Shenlong Li, Ruikun Pang, Jing Liu 
  Abstract: In planetary gear transmission systems, when the position errors exist between the gear and the axle hole, the vibrations and fatigue life of the systems may be affected. However, the influences of the position errors are rarely considered in the previous dynamic modelling methods for the planetary gear systems (PGSs). To solve this problem, a PGS with six planetary gears is established. The effects of the position errors on the vibrations of PGSs are analysed. Different position error cases between the planetary gears and the planetary shaft are considered in the model, as well as the bearings with the radial clearance. The vibration characteristics from the proposed model with the position errors are compared with those of the normal model. The position errors in the planetary gears of the PGSs can increase its vibration level. This study can provide a new method for detecting the position errors in the PGSs.
  Keywords: position error; gear transmission; vibration characteristic.
  DOI: 10.1504/IJPT.2023.10053382
   
  
• Thermal efficiency predictive modelling of dedicated hybrid engines based on an optimal multi-network structure
  by Chengqing Wen, Ji Li, Quan Zhou, Guoxiang Lu, Hongming Xu 
  Abstract: This paper presents an evolutionary data-driven modelling approach for dedicated hybrid engine thermal efficiency (TE) prediction, in which a multi-network structure is developed to further improve the prediction accuracy. This structure enables adaptively segmenting input channels in order to reduce the nonlinearity of data representation in each channel so that the sub-networks can be trained efficiently. In the context, the grey wolf optimisation (GWO) algorithm is applied to find the breakpoints of segmentation for building an optimal multi-network structure. The multilayer perceptron (MLP) is introduced as the basic network due to its simple structure with only two hidden layers. Validated by the experimental data, the accuracy of the multi-network prediction model incorporating GWO improves from 82% to 89%. Also, GWO converges to the optimal solution with 21 iterations compared to 26 for particle swarm optimisation and 31 for the gravitational search algorithm, which demonstrates that GWO has a better performance in this study.
  Keywords: optimal network structure; engine thermal efficiency; grey wolf optimisation algorithm; data-driven modelling.
  
  
• The matching model of thermal energy supply and demand in power generation park with new energy and municipal solid waste  
  by Jia Zhang, Wei Wu 
  Abstract: This paper focuses on the matching problem of thermal energy supply and demand in the power generation park with new energy and municipal solid waste, and constructs a matching model of thermal energy supply and demand in the power generation park with new energy and municipal solid waste. Firstly, the distributed energy supply base model of supply side is built to analyse the thermal energy supply in the park. Then, the optimal scheduling model of the supply and demand of the park’s thermal energy system. The particle swarm optimisation algorithm with good global searching ability is used as the model solving algorithm. Finally, the effectiveness of the model is verified by a specific example. The results show that the matching scheme of heat energy supply and demand in the park under the economic and environmental protection goals is obtained, so it has good application effect and certain use value.
  Keywords: new energy; municipal solid waste; power generation; park; heat supply and demand; matching model.
  DOI: 10.1504/IJPT.2023.10055385
   
  
• Design of impulse grounding resistance measurement system for distribution network based on wavelet packet optimal algorithm  
  by Qing Wang, Na Yu, Chencong Jin 
  Abstract: Accurate measurement of distribution network grounding resistance is helpful to improve the lightning protection performance of distribution network transmission lines. However, traditional measurement methods can not completely eliminate the invalid interference information in the signal. Therefore, a measurement system for impulse grounding resistance of distribution network based on wavelet packet optimisation algorithm is designed. Compared with traditional systems, this measurement system can more effectively and orderly extracts and process information with wavelet packet optimisation algorithm. The impact current generator is used to generate the impact current. The acquisition board and the main control unit are isolated by V/F transformation module and infrared communication module. In terms of software, the initial resistance signal measurement value is calculated based on the system measurement principle, and the initial resistance signal is processed by the wavelet packet optimal algorithm to remove the interference signal and retain the effective signal reflecting the ground resistivity information. It is verified that the designed system has high measurement precision. It is a highly reliable system for measuring the impulse grounding resistance of distribution networks.
  Keywords: wavelet packet; optimal algorithm; distribution network; impulse current; impulse grounding resistance; resistance signal; measurement system.
  DOI: 10.1504/IJPT.2023.10055386
   
  
• Energy Management of Hybrid Electric Vehicle Based on Linear Time-varying Model Predictive Control  
  by Daofei Li, Jiajie Zhang, Dongdong Jiang 
  Abstract: Energy management of hybrid electric vehicle (HEV) is crucial for improving fuel economy and reducing emissions. Due to the challenges in both development and implementation, sim-plified algorithms of energy management, e.g. rule-based strategies (RB) and equivalent con-sumption minimization strategy (ECMS), still prevail in real vehicle applications. Taking an entry level passenger vehicle with P2 hybrid powertrain for an application example, a bilevel hybrid model predictive control (Bi-HMPC) algorithm is proposed to improve fuel economy of HEV. The upper level calculates the optimal engine/motor torque distribution based on linear time-varying model predictive control (LTV-MPC) algorithm, while the lower level optimizes the gear ratio via hybrid MPC (HMPC). Preliminary simulations demonstrate that the Bi-HMPC has better fuel-saving performances than ECMS and has the potential for practical application. Considering practical difficulties in real vehicle application, the LTV-MPC based torque distri-bution optimization algorithm in the upper level is further implemented in real vehicle valida-tion through dynamometer tests. The initial test, without applying any special limits of engine start or maximum torque, shows that the vehicle fuel consumption is still as high as 7.05L/100km and pollutant emissions are also high. Through several optimizations and im-provements based on expert rules, e.g. optimizing the starting condition of the engine, we can reduce the fuel consumption from 7.05L/100km to 6.2L/100km. Results of real-vehicle experi-ments show that the LTV-MPC algorithm can realize real-time operation on HEV, together with noticeable improvements in fuel economy and pollutant emissions of the tested HEV.
  Keywords: Hybrid Electric Vehicle; Energy Management; Linear Time Varying Model Predictive Control; Fuel Economy; Real Vehicle Tests.
  
  

Special Issue on: ICAVP2021 Latest Advancements in Vehicular Powertrain Electrification

• Influence of Valve Spool Shoulder Wall Angle on Steady-state Hydraulic Force  
  by Zi-wei Wang, Shuai Gao, Jian-ren Zhu 
  Abstract: In order to improve the control precision and response speed of electro-hydraulic control system, this paper studies the influence of angle at the shoulder of the main pressure regulating valve spool of a transmission hydraulic system on steady-state hydraulic force of slide valve. The axial hydraulic force on the valve spool with fixed valve opening is calculated by theoretical empirical formula and computer simulation, the results show that the force on the spool is large. To reduce the influence, the steady-state hydraulic force with different shoulder angles is calculated. The results show the law of the hydraulic force when the angle of incident and exit is changed separately.
  Keywords: Main pressure regulating valve; Steady-state hydraulic force; Fluent.
  
  
• Experimental study on effect of torsional vibration attenuation measures for driveline with DCT  
  by Dong Guo, Wenyi Rao, Yi Zhou, Yizhou Xiong, Yi Zhou 
  Abstract: Interior noise and vibration has become one key issue of vehicle with DCT, which has a low gear rattle noise threshold. Four types of torsional vibration attenuation measures, including clutch torsional damper, dual mass flywheel, clutch micro-slip control and centrifugal pendulum vibration absorber are adopted to the DCT driveline. Then road test is conducted and the angular acceleration of the primary flywheel and gearbox input shaft are measured under fourth gear acceleration condition. It is found that the torsional shock absorption performance of the original clutch torsional damper is the worst. The angular acceleration amplitude of the input shaft is greatly reduced by using dual-mass flywheel and clutch micro-slip control, respectively. Dual-mass flywheel with centrifugal pendulum vibration absorbers torsional shock absorption performance is the best?the input shaft angular acceleration is always less than 100 rad/s
  Keywords: Torsional vibration experimental; attenuation measures; clutch micro-sliprncontrol; Centrifugal pendulum.
  
  
• Modelling of a Magnetorheological Fluid Dual Clutch with BP Neural Network  
  by Jin Zhao, Haiping Du, Donghong Ning, Huan Zhang, Lei Deng, Weihua Li 
  Abstract: In this paper, a backpropagation (BP) neural network model for a novel Magneto-rheological fluid dual-clutch (MRFDC) is presented. The MRFDC is a complicated system with high nonlinearity and strong hysteresis, and the conventional parametric modelling methods are based on parameter identification and optimisation. Thus, the modelling work is usually difficult and the performance of conventional models is usually not good enough for the MRFDC. In contrast, the proposed BP neural network model in this work is easily obtained and able to precisely describe the input and output relationship of the MRFDC. To be specific, the proposed BP neural network model approximates the dynamic behaviours of the MRFDC regarding dynamic input currents and rate-dependent hysteresis. The model input variables are selected considering the working mode of the MRFDC and its rate-dependent dynamic magnetic hysteresis. Then, the BP neural network is trained by the input and output data sets obtained from experiments. The model performance is validated by experiments, and experimental results show that the proposed model is able to predict the output torque capacity of the MRFDC precisely with dynamic input currents.
  Keywords: BP Neural Network; Magnetorheological Fluid; Magnetorheological Clutch.
  
  
• A Hybrid Electromechanical Coupling System Optimization  
  by Xuewu Liu, Jiangling Zhao, Zhuochao Liu, Xiangyang Xu, Hongzhong Qi, Yongming Zhu, Peng Dong, Shuhan Wang 
  Abstract: Hybrid electric vehicles can not only save energy and reduce emissions, but also solve the range anxiety problem of electric vehicles, therefore becoming an important breakthrough direction of low-carbon vehicles. The electromechanical coupling system is an important part of hybrid electric vehicles, including the single-motor hybrid system, the series-parallel hybrid system, the power-split hybrid system, and other different routes. First, three basic configurations are established for the three technical routes respectively. Then, the optimal configuration of each basic configuration is obtained through optimization analysis. Finally, the series-parallel technical routes are confirmed by comprehensive comparison, and the configuration design is carried out. This paper systematically describes the whole process of scheme design, which can provide reference for other automobile companies that develop electromechanical coupling systems for hybrid electric vehicles.
  Keywords: hybrid electric vehicles; electromechanical coupling system; basic configuration; optimal configuration; scheme optimization.
  
  
• Gear Condition Monitoring by Augmenting Measured Transmission Error Data for Gear Damage and Propagation Estimation  
  by Stefan Sendlbeck, Shiv Patel, Michael Otto, Karsten Stahl 
  Abstract: Structural changes and damage to gears can lead to critical failure of gear transmission systems. However, current condition monitoring approaches often lack precision due to the limited availability of labelled run-to-failure data. Therefore, we provide an approach to augment measured transmission error data with simulated data. The simulation is based on tactilely measured gear flanks with (micro)pitting of varying severity. We automatically identify (micro)pitting with respect to the gear flank and subsequently simulate geometrical and temporal damage growth. This allows us to compute the temporal change in (micro)pitting expansion, as well as the resulting transmission error. By comparing this simulated with the measured transmission error of the running gear transmission, an estimate of the current degree of gear damage is possible. The presented approach offers to combine state-of-the-art damage propagation models with a dataset of measured gear flanks and data augmentation to determine the health condition of gear transmissions.
  Keywords: Condition Monitoring; Damage Detection; Damage Propagation; Gears; Gear Damage Simulation; Data Augmentation; Transmission Error; Gear Topography; Flank Measurement.
  
  
• Real-time load spectrum analysis for Lifetime Prediction of E-Mobility Drivetrains  
  by Michael Otto, Stefan Sendlbeck, Karsten Stahl 
  Abstract: The drivetrain is a critical subsystem in vehicles, because any failure stops mobility and therefore current drivetrains are designed to be nearly fail-safe despite widely differing operating conditions and drivers of road vehicles. This applies especially to the main gearbox and is a special challenge for e-mobility, where weight reduction is mandatory. Optimization may be possible by using vehicle-specific service intervals based on real driving loads. As a result, lighter gearboxes can be used and a predamage warning and service is only required for demanding drivers or regular high load conditions. As a consecutive effect this may also allow lighter design of the rest of the drivetrain. Therefore, in this manuscript an innovative approach is presented to tackle this challenge by using a novel strategy of combining load spectrum calculation and condition monitoring that adjusts the lacking precision of lifetime prediction.
  Keywords: Transmission; Load spectrum calculation; Condition Monitoring; E-mobility.