Drive Torque Control Research Articles

Research on Optimal Driving Torque Control Strategy for Multi-Axle Distributed Electric Drive Heavy-Duty Vehicles

Multi-axle distributed electric drive heavy-duty vehicles have the characteristics of high transmission efficiency, strong maneuverability, and good passability, making them widely used in large cargo transportation. However, the current driving torque control strategies of multi-axle distributed electric drive heavy-duty vehicles lack comprehensive consideration of their longitudinal and lateral dynamic characteristics, making it difficult to comprehensively optimize multiple performances such as power economy, comfort, and stability. In order to solve the above problems, This work focuses on a five-axle distributed electric drive heavy-duty vehicle. Firstly, given the differences in dynamics between two-axle vehicles and multi-axle vehicles, the dynamic model of the multi-axle distributed electric drive heavy-duty vehicle and its critical components is constructed. Then, by analyzing the characteristics of power economy, comfort, and stability of the multi-axle distributed electric drive heavy-duty vehicle, an optimal driving torque control strategy based on multiple performance coordination is proposed. Finally, on the hardware-in-the-loop (HiL) platform, the performance of the optimal driving torque control strategy proposed in this paper is verified by using the China Heavy-Duty Commercial Vehicle Test Cycle for Truck (CHTC-HT) and a straight-line acceleration driving condition on a split friction road. The simulation test results show that, compared with the traditional torque average distribution strategy, the proposed optimal driving torque control strategy can reduce the energy consumption rate by 3.45% in CHTC-HT. The strategy is attributed to the driving torque distribution based on the vehicle’s optimal instantaneous energy consumption, and vehicle comfort is also ensured by the driving mode switching frequency suppression. Subsequently, the vehicle’s stability on the split friction road is effectively improved by the torque coordination compensation strategy. This control strategy significantly improves the comprehensive performance of multi-axle distributed electric drive heavy-duty vehicles.

Driving Torque Control of Dual-Motor Powertrain for Electric Vehicles

This paper investigates the driving torque control method for the dual-motor powertrain in electric vehicles (EVs) to achieve the performance of accurate vehicle speed tracking, seamless driving mode shift, and high energy efficiency. The configuration of the dual-motor powertrain is based on the parallel axle transmission structure, which does not contain any clutch or synchronizer. The powertrain provides three driving modes that are two single-motor driving modes and one dual-motor combined driving mode. A detailed dynamic model of the dual-motor powertrain is built to simulate the dynamic response of an EV. An energy management strategy (EMS) is used to select the driving mode and determine the ideal driving torque of two motors. The dynamic control strategy tries to track the ideal vehicle speed when uncertain parameters existed and avoid power interruption or impact during the mode shift. Three dynamic control strategies are proposed, which are the backward dynamic control strategy (BDCS), combined forward and backward dynamic control strategy (CFBDCS), and nested forward and backward dynamic control strategy (NFBDCS). The simulation results demonstrate that the NFBDCS has the best comprehensive performance in vehicle speed tracking, seamless mode shift, and good system energy efficiency.

Modelling and stability analysis of a longitudinal wheel dynamics control loop with feedback delay

Vehicle safety is an important field of today's engineering practice and the scientific research as well. One of the basics of the modern vehicle system dynamics control systems is braking or driving torque control. Ensuring proper connection between the tyre and the road surface is essential for safety and good handling behaviour. Fundamental questions may arise about the details of the model, such as feedback delay, sampling effect, numerical differentiation in the control algorithm or the dynamical characteristics of the tyre model. In this article, a connected dynamical system is presented which contains a wheel model and a PID type traction controller. Steady state and dynamical brush type tyre models are presented and compared. Two different ways are described to model the feedback delay. The fully continuous time model contains constant time delay, while there is another case, where the sampling effect and the numerical differentiation methods of the control algorithm are presented. Finally, stability analysis of the delayed system is performed. The stability and performance characteristics and different bifurcations are presented using stability charts. The type of the tyre model has significant effect on the stability characteristics.

Driving mode shift control for planetary gear based dual motor powertrain in electric vehicles

To reduce the vehicle jerk in mode shift, this paper investigates the driving torque control strategies of the planetary gear based dual motor powertrain. The rigid dynamic model of powertrain is built to formulate a general energy management strategy (EMS) and a robust EMS which avoids the drastically change of motors speed. A flexible dynamic model considering the flexible shafts is then built to accurately simulate the vehicle jerk. Based on the linear and polynomials function, two types of coordinated speed trajectories of motors are designed to transfer the discrete speed signals produced by EMS to continuous signals. A speed feedback control strategy and a combination control strategy of speed feedback and torque feedforward are proposed to implement the mode shift. The comparisons between EMS and robust EMS, linear and polynomials speed trajectories, speed feedback control and combination control are demonstrated by simulation. The results indicate that the robust EMS and polynomials speed trajectories can reduce vehicle jerk. The speed feedback control strategy is more stable than the combination control strategy when the model parameters are inaccurate.

Yaw stability control through independent driving torque control of mid and rear wheels of an articulated bus

This paper describes a novel yaw stability control strategy for a four-wheel-independent-drive electric articulated bus with four motors at the middle and rear wheels. The proposed control strategy uses a hierarchical control architecture. In the upper layer, a 3 degree-of-freedom reference model is established to obtain the desired vehicle states and the desired yaw moments of the front and rear compartments are determined by means of sliding mode control, respectively. The lower layer distributes differential longitudinal forces according to the desired yaw moments based on quadratic programming theory. The tire utilization rate is used as the optimization goal considering the actual constraints. To verify performance, three test cases are designed on the dSPACE-ASM simulation platform. The test results show the proposed control strategy can improve the yaw stability and the trajectory following performance of the bus under different driving conditions.

Analysis of regulation indicators in schemes with subordinate regulation and modal control of electric drive of feeding mill for cold rolling tube

The article is devoted to the issue of selection of the preferred structure of a positional electric drive of the feeding mill for a cold rolling tube by the criterion of minimum feed overshoot and, as a consequence, minimum polythickness of the tube. The cut-off frequency limit of a torque control loop is determined as 200 rad/s, for which the subordinate regulation is optimal. If the value of this parameter is high, then the modal control is preferred. This article consists of recommendations how to choose an actual control system according to processing speed opportunities of an electric drive torque control loop.

Parallel Control for Hybrid Propulsion of Multifunction Ships

Multifunction ships, naval vessels in particular, need to reduce fuel consumption while maintaining manoeuvrability. Hybrid propulsion that runs a main diesel engine and electric drive in parallel can achieve this. However, a parallel control strategy needs to be developed. In this paper, we use a simulation model of a hybrid propulsion system to investigate two parallel control strategies for diesel mechanical and electrical propulsion on multifunction ships. For the case study frigate, parallel control can increase the ship top speed with 3 kts when using two 4 MW electric drives and two 10 MW main diesel engines, compared with the same baseline hybrid propulsion without parallel control. The diesel engine speed control with electric drive torque control strategy increases ship acceleration rate with 17% and reduces average engine thermal loading with 150 K. Moreover, the electric drive speed control with diesel engine torque control strategy can improve acceleration rate by 40%, while eliminating thermal loading fluctuation due to heavy seas, and also reducing engine average thermal loading with 150 K. Future combination of the proposed electric drive speed control strategy with an adaptive pitch control and optimal power split strategy can potentially further increase hybrid propulsion plant performance.

후륜 구동 인휠 전기 자동차의 구동 및 현가 통합제어시스템

An in-wheel motor vehicle is a type of car that is equipped with an electric motor for each wheel. It is possible to acquire vehicle stability through a seperate driving torque control per wheel, since it directly generates the driving torque via the wheel motors. However, the vehicle ride comfort and road holding performance worsen depending on the increase of the wheel weights. In order to compensate for the impaired performance, an integrated chassis control system of the rear in-wheel motor vehicle is proposed. The proposed integrated chassis control system is composed of a driving torque control system, a semi-active suspension system, and an ESC system. According to the vehicle dynamic simulation of an in-wheel motor vehicle equipped with the integrated chassis control system, it is found that the system can improve the driving stability, ride comfort, and driving efficiency of the in-wheel motor vehicle.

후륜 인휠 모터 전기자동차의 구동 및 반능동 현가시스템 동시 제어를 통한 주행 성능 분석

Abstract : Recently, the in-wheel motor vehicle is rapidly developed to solve energy exhaustion and environmental problems. Especially, it has the advantage of independently driving the torque control of each wheel in the vehicle. However, due to the weight increase of wheel, the comfort of vehicle riding and performance of road holding become worse. In this paper, to compensate the poor performance, a simultaneous control of the driving torque and semi-active suspension system is investigated. A vehicle model is generated using CarSim Software and validated by field tests. Co-simulation of CarSim and MATLAB/Simulink with control logics is carried out, and it is found that simultaneous control of the driving torque and semi-active suspension system can improve driving stability and durability of the in-wheel motor system. Key words : Electric vehicle(전기자동차), In-wheel motor(인휠 모터), Vehicle dynamics(차량동역학), Driving torque control(구동 제어), Semi-active suspension system(반능동 현가시스템), Simultaneous control( 동시제어)

Driving torque control method for electric vehicle with in‐wheel motors

AbstractAntislip control or slip ratio control can help improve the stability of EVs on a low‐μ road. However, these control methods cannot control the driving torque. In this paper we propose a driving torque control method for EVs with in‐wheel motors. By using this method we can control the driving torque directly. Simulations and experiments are carried out to demonstrate the effectiveness of the proposed method. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(3): 49‐58, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21286

Development of an EV Drive Torque Control System for Improving Vehicle Handling Performance Through Steering Improvements

At Nissan we have developed many different environmental technologies to date and launched sales of an electric vehicle (EV) in December 2010 that achieves zero carbon dioxide and zero exhaust emissions. Besides its outstanding environmental performance, this zero-emission EV also embodies new potentialities not found in conventional gasoline-engine vehicles. The responsiveness and controllability of the electrified powertrain (EV drive motor) combine to provide an unprecedented driving experience that transforms conventional thinking about automobiles.This paper presents an EV drive torque control system that takes advantage of this EV-unique performance to provide handling capabilities for driving ease that anyone can enjoy.

Experiment and Study of Electric Control Loading System

According to the aircraft control load power model, using electric power servo loading approach in designing the aircraft simulator electric control loading system, introduced a control loading system works as well as excess power causes. According to the direct driving torque control servo motor applied characteristics of double by force, and the compensation of hybrid control strategy. Using force is the inner loop, current loop using. At the same time as manipulate load system, we can adopt " Structure invariability principle " compensation strategies that speed compensation measures to abate force to influence on the performance of the control system. Experiment measures to eliminate that speed compensation system of plus torque, and good results have been achieved. Simulation results show that, using the hybrid control strategy can effectively eliminate the surplus torque control steady-state error, tracking precision, to force the requirements for the construction, performance control principle prototype system load provides data parameters and the control strategy.

Steady-state drifting stabilization of RWD vehicles

A control scheme to stabilize rear-wheel-drive (RWD) vehicles with respect to high-sideslip cornering (drifting) steady-states using coordinated steering and drive torque control inputs is presented in this paper. The choice of coordinated control inputs is motivated by the observed data collected during the execution of drifting maneuvers by an expert driver. In addition, the steering and drive torque input variables directly correlate to a human driver's steering wheel and throttle commands. The control design is based on a comprehensive vehicle model with realistic tire force and drive-train characteristics, and validated in a high-fidelity simulation environment.

Driving Torque Control Method for Electric Vehicle with In-Wheel Motors

Antislip control or slip ratio control can help improve the stability of EVs on a low-μ road. However, these control methods cannot control the driving torque. In this paper we propose a driving torque control method for EVs with in-wheel motors. By using this method we can control the driving torque directly. Simulations and experiments are carried out to demonstrate the effectiveness of the proposed method. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(3): 49-58, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21286

3308 車両の動特性を考慮したハイブリッドトラックの駆動力制御に関する研究(OS3-2:車両運動制御の電動化技術,OS3:交通・物流システムの制御,オーガナイズド・セッション(OS),第18回交通・物流部門大会(TRANSLOG2009))

3308 車両の動特性を考慮したハイブリッドトラックの駆動力制御に関する研究(OS3-2:車両運動制御の電動化技術,OS3:交通・物流システムの制御,オーガナイズド・セッション(OS),第18回交通・物流部門大会(TRANSLOG2009))

3210 車両挙動を考慮したハイブリッドトラックの駆動力制御に関する研究(OS5-2 効率化,環境負荷低減の技術,OS5 安全・安心・防災・環境負荷低減,オーガナイズド・セッション)

3210 車両挙動を考慮したハイブリッドトラックの駆動力制御に関する研究(OS5-2 効率化,環境負荷低減の技術,OS5 安全・安心・防災・環境負荷低減,オーガナイズド・セッション)

Effect of Positive Angular Velocity Feedback on Torque Control of Hydraulic Actuator.

Output torque/force of a hydraulic actuator is generally affected by its driving speed. This may cause deterioration of the control accuracy of the system in which the plant is controlled through the driving torque/force control of the actuator. This study proposes a positive angular velocity feedback for compensation of the effect of the driving speed on the driving torque control of a rotary hydraulic actuator. The compensation scheme is experimentally applied to motion control of a one-link hydraulic robot which is controlled by means of the computed torque method. The experiments show that the compensation scheme is effective in isolating the driving torque of the actuator from its driving speed and slightly improves the tracking accuracy of the motion control.

Effect of Positive Angular Velocity Feedback on Torque Control of Hydraulic Actuator.

Output torque/force of a hydraulic actuator is generally affected by its driving speed. This may cause deterioration of the control accuracy of the system in which the plant is controlled through the driving torque/force control of the actuator. This study proposes a positive angular velocity feedback for compensation of the effect of the driving speed on the driving torque control of a rotary hydraulic actuator. The compensation scheme is experimentally applied to motion control of a one-link hydraulic robot which is controlled by means of the computed torque method. The experiments show that the compensation scheme is effective in isolating the driving torque of the actuator from its driving speed and slightly improves the tracking accuracy of the motion control.