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For an electric vehicle with independently controlled motors, because of design and manufacturing factors, the steady-state error of each motor output torque, and the flexibilities and nonlinear backlash of left and right drivetrains, can be different. ...Thanks to the actuation flexibility of their systems, electric vehicles with individual powertrains, including in-wheel and on-board motors, are a very popular research topic amongst various types of electrified powertrain architectures. ...In this study, a novel method of directional stability enhancement through robust control of blended braking of an electric vehicle equipped with four individual on-board motors during normal straight-line deceleration are studied. System models, including the vehicle dynamics, tire, electric powertrain, and hydraulic brake models, are developed.

This paper presents a coordinated controller for comprehensive optimization of vehicle dynamics performance and energy consumption for a full drive-by-wire electric vehicle, which is driven by a four in-wheel motor actuated (FIWMA) system and steered by a steer-by-wire (SBW) system. In order to coordinate the FIWMA and SBW systems, the mechanisms influencing the vehicle dynamics control performance and the energy consumption of the two systems are first derived.

A novel fault tolerant brake strategy for In-wheel motor driven electric vehicles based on integral sliding mode control and optimal online allocation is proposed in this paper. ...The In-wheel motor can generate both driving torque and braking torque according to different vehicle dynamic demands. ...In braking procedure, In-wheel motors generate electric braking torque to achieve energy regeneration. The strategy is designed to make sure that the stability of vehicle can be guaranteed which means vehicle can follow desired trajectory even if one of the driven motor has functional failure.

Analysis of these experiment results shows that optimization of clutch control and cooperation of the engine and the motor on speed and torque are effective in reducing the jerk of vehicle.

Simulation results show that the motor brake torque works cooperatively with hydraulic brake force. More than 36% of recoverable energy can be regenerated during typical braking procedure.

Specifically, since the regenerative braking capability of the motor is affected by the SoC of battery and motors torque limitation in real time, the dynamical variation of the regenerative brake efficiency is considered in this study. ...Quasi static system models, including the vehicle model, the motor, the battery, the transmission system, and drive cycles are established in MATLAB/Simulink at first. ...During the optimization process, the motor efficiency is observed along with the drive cycle, and the gear shift strategy is determined based on the vehicle velocity and acceleration demand.

As the main power source of the electric vehicle, the electric motor has outstanding characteristics including rapid response, accurate control and four-quadrant operation. ...Being introduced into the dynamic chassis control of electrified vehicles, the electric motor torque can be used not only for driving and regenerative braking during normal operating conditions, but also offers a great potential to improve the dynamic control performance of the anti-lock braking under emergency deceleration situations. ...This paper presents a robust control algorithm for anti-lock braking of a front-wheel-drive electric vehicle equipped with an axle motor. The hydraulic and regenerative braking system of the electric vehicle is modeled as a LPV (linear parameter varying) system.

In the research of this paper, the motor model, battery model, and vehicle dynamics model are firstly established by using MATLAB/Simulink, and the dynamic relationship between regenerative current and regenerative braking torque is analyzed at the same time. ...Finally, the SPPC control strategy is effectively verified by the motor test bench.

In this study, a nonlinear powertrain of an electric passenger car equipped with a central motor is modeled using hybrid system approach. The effect of powertrain backlash gap on vehicle drivability during regenerative deceleration is analyzed.

Finally, the hardware-in-loop (HIL) test bench based on the real motor system is set up to validate the conclusion drawn in the simulation analysis. The results show that compared with the conventional hydraulic braking system, CRABS system proposed in this paper conducts faster in braking response and closer to the ideal braking distance, and the performance of active collision avoidance is improved.

The third is the motor control optimization. Motor power or power generation can be employed to restrict or stabilize engine load within a certain range so as not to impact original emission levels due to load variations. ...The strategy for emission reduction in the P2.5 hybrid system involves the optimization of engine torque, engine speed, catalyst heat duration, and motor torque regulation in a coordinated manner. In addition to employing traditional engine control methods used in HEV models, unique approaches can be utilized to effectively manage emissions. ...In the first stage, the vehicle is driven by the motor while keeping the engine idle. This approach stabilizes catalyst heating and prevents fluctuations in air-fuel ratio caused by speed and load changes that could potentially worsen emissions performance.

In order to improve the overall performance of the voltage control strategy, the voltage control strategy of the boost converter is dynamically adjusted by feeding the motor running state to the converter in real time, and the bus voltage is optimized. The motor application of the FOC strategy in the hybrid power system is the battery thermal control. ...This paper analyzes the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. Current control includes current vector control, MTPA control, flux weakening control, PI current control and SVPWM control. ...Current control includes current vector control, MTPA control, flux weakening control, PI current control and SVPWM control. Motor mode includes initialization mode, normal mode, fault mode, active discharge mode, power off mode, battery heating mode and boost mode.

Due to the high speed adjustment accuracy and fast response of the P1 motor, the input shaft is preferentially allocated to P1 for speed adjustment, that is, the torque intervention of P1. ...In the clutch combination stage, by identifying the motor speed change in the oil filling stage and the shifting stage, the current mode switching under test and the oil filling effect of the shifting clutch are evaluated, and the current mode switching under test and the KP point state of the shifting clutch are judged.

Tests were conducted on both a motor bench and a sample car to investigate how motor speed and 12V load affect voltage control mode performance. ...In order to achieve seamless mode switching control for hybrid electric vehicles (HEVs) in the event of battery failure, we propose a motor voltage-controlled mode switching method that eliminates power interruptions. This approach is based on an analysis of the dual-motor hybrid configuration's mode switching. ...In this mode, instead of operating in its traditional torque control manner, the P1 motor adopts a voltage control strategy. The P1 controller's variable becomes "voltage," and VCU sends the motor's working mode switching request and PCM finishes the mode transition.

When the amplitude of the engine speed is greater than that of the motor speed and the phase of the engine speed is different from that of the motor speed, if the motor damping control is still adopted, the engine speed jitter cannot be eliminated due to the phase difference. ...The engine torque filtering control method based on the slope limit was adopted to limit the rate of change of the engine torque and reduce the impact caused by the sudden change of the engine torque; the engine speed closed-loop control method was used to take the motor speed which is easy to be measured accurately in real time as the feedback control variable, which solved the problem of the real-time accurate estimation of the engine torque online. ...In parallel mode, the motor torque accounts for a small proportion because the torque distribution method gives priority to the engine.

With the active damping control of the motor, the peak of motor speed fluctuation decreased by 48% before optimization, and the vehicle impact is suppressed to 44.35% before optimization. ...In hybrid vehicles, the drive motor is directly connected to the drive train and the inherent drive train damping is low. When subjected to external disturbance, the low damping characteristics of the transmission system may cause torsional vibration, which will continue to oscillate the transmission system and affect the driving performance of the vehicle. ...In this paper, we propose a harmonic injection wheel control method based on motor speed to suppress oscillations and improve the driving performance of hybrid electric vehicles.

Lastly, in the fourth transition scenario, as a safety measure, engine start is initiated by engaging the C0 clutch using the P2 motor when the P1 motor is in fault mode. Finally, successful real vehicle tests demonstrate significant improvement in drivability performance achieved through our innovative control strategy. ...Due to the objectives of achieving high fuel efficiency and drivability performance, a dual-drive hybrid system with two motors has been developed. Various drive modes are presented based on engine status, requested driver torque and power, as well as C0 status in different working conditions.

Shift control includes shift type decision, shift sequence control, shift inertia process based on motor intervention. Thermal management includes clutch flow and motor flow distribution. Motor control include the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. ...DHT hybrid transmission assembly control system discussed in this paper includes hydraulic control, hybrid mode switching control, shift control, dual motor control, clutch and motor thermal management. The hybrid mode is divided into four modes: the EV mode, the serial mode, the parallel mode and the launch mode. ...Motor control include the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. Motor mode includes initialization mode, normal mode, fault mode, active discharge mode, power off mode.

In the speed regulation stage, the torque distribution control problem of the speed phase including which actuator (P1, engine, C0 clutch) is used preferentially for speed regulation. a) If the speed regulation torque assigned to the input shaft exceeds the input shaft intervention torque capacity, then the excess part is assigned to the clutch for speed regulation. b) If the speed regulation torque assigned to the input shaft is less than the input shaft intervention torque capacity and the speed regulation torque assigned to the input shaft is less than the motor 2 speed regulation torque intervention capacity, the speed regulation torque is assigned preferentially to P2 for lifting torque. ...The total P2 request torque for P2 is equal to the sum of the speed regulation torque intervention of P2 and the P2 torque requested by ECM because of the fast response and high precision of the motor. c) If the governing torque assigned to the input shaft is less than the input shaft intervention torque capability and the governing torque assigned to the input shaft is greater than the motor 2 governing torque intervention capability, the excess is assigned to the engine. ...The total P2 request torque for P2 is equal to the sum of the speed regulation torque intervention of P2 and the P2 torque requested by ECM because of the fast response and high precision of the motor. c) If the governing torque assigned to the input shaft is less than the input shaft intervention torque capability and the governing torque assigned to the input shaft is greater than the motor 2 governing torque intervention capability, the excess is assigned to the engine. The total engine requested torque is equal to the sum of the engine governing torque intervention and the engine torque requested by the ECM.