Content uploaded by Chen Lv
Author content
All content in this area was uploaded by Chen Lv on Jul 10, 2015
Content may be subject to copyright.
Abstract
Regenerative braking, which can effectively improve vehicle's
fuel economy by recuperating the kinetic energy during
deceleration processes, has been applied in various types of
electried vehicle as one of its key technologies. To achieve
high regeneration efciency and also guarantee vehicle's brake
safety, the regenerative brake should be coordinated with the
mechanical brake. Therefore, the regenerative braking control
performance can be signicantly affected by the structure of
mechanical braking system and the brake blending control
strategy.
By-wire brake system, which mechanically decouples the brake
pedal from the hydraulic brake circuits, can make the braking
force modulation more exible. Moreover, its inherent
characteristic of ‘pedal-decouple’ makes it well suited for the
implementation in the cooperative regenerative braking control
of electried vehicles.
With the aims of regeneration efciency and braking
performance, a regenerative braking control algorithm for
electried vehicles equipped with a brake-by-wire system is
researched in this paper. The layout of the adopted brake-by-
wire system is introduced. The proposed regenerative braking
control algorithm is illustrated. To validate the control
performance of the algorithm, hardware-in-the-loop simulations
are carried out. The simulation results show that, based on
brake-by-wire system, the proposed control algorithm,
coordinating regenerative brake and hydraulic brake well, can
further improving the regeneration efciency of electried
vehicle and guarantee the braking performance in the
meantime.
Introduction
The ever heavier burden on the environment and energy
requires automobiles to be cleaner and more efcient. Studies
show that, in urban driving situations, about one third to one
half of the energy of the power plant is consumed during
braking [1, 2, 3, 4, 5]. Among the key features of electric
vehicles, regenerative braking system (RBS) offers the
capability to improve the fuel economy effectively by converting
vehicle's kinetic energy into electric energy during deceleration
processes. It has become a key topic of research and
development among automotive makers, component suppliers,
and research institutes worldwide.
Most of the commercialized electried vehicles now are
equipped with a regenerative braking system. However, to
guarantee the vehicle's brake performance, a mechanical
brake is still needed. Since the regenerative braking force and
the friction braking force are coordinated during the
deceleration processes, the brake blending performance can
be signicantly affected by the mechanical braking system and
the regenerative braking control strategy [2]. Therefore,
researching the effective control strategy based on an
appropriate brake system is of great necessity and importance.
To keep the blended braking force consistent with driver's
braking request and maximize the regeneration efciency, the
friction braking force needs to be regulated cooperatively in
real-time based on the variation of the regenerative braking
force provided by the electried powertrain. However, in a
conventional brake system, the brake pedal is mechanically
connected to the hydraulic brake circuit, resulting in the brake
pedal feel being affected by hydraulic pressure modulation
during brake blending. Hence, mechanical decoupling of the
brake pedal from the hydraulic brake circuit is required in a
regenerative braking system of an electried vehicle.
Brake-by-wire system, which mechanically decouples the
brake pedal from the actuation of the mechanical brake
devices, can make the braking force distribution and
modulation between the front and the rear axles more exible
[6, 7, 8]. It was initially developed to improve the dynamic
performance of conventional ICE vehicles and has been
Regenerative Braking Control Algorithm for an
Electried Vehicle Equipped with a By-Wire Brake
System
2014-01-1791
Published 04/01/2014
Chen Lv, Junzhi Zhang, Yutong Li, and Ye Yuan
State Key Lab of ASE, Tsinghua Univ.
CITATION: Lv, C., Zhang, J., Li, Y., and Yuan, Y., "Regenerative Braking Control Algorithm for an Electried Vehicle
Equipped with a By-Wire Brake System," SAE Technical Paper 2014-01-1791, 2014, doi:10.4271/2014-01-1791.
Copyright © 2014 SAE International
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
applied in some commercialized cars. However, its inherent
‘pedal-decouple’ structure make it well suited for the
implementation of the cooperative regenerative braking control.
Automotive makers and component suppliers worldwide have
developed several RBS solutions for electried vehicles based
on ‘brake-by-wire’ concept. Toyota developed the ECB
(Electronically Controlled Brake) system, which has been
brought into series production and implemented successfully in
commercialized HEV Prius [9]. Hitachi proposed the EDiB,
which has been employed in the pure electric vehicle Nissan
Leaf [10]. And Hyundai, Continental, Honda, and Borsch etc.
have developed regenerative braking systems for electried
vehicles based on by-wire concept as well [11, 12, 13].
Researchers also have carried out some studies in this area. Ko et
al. proposed a cooperative regenerative braking control algorithm
for an EV equipped with EWB and EMB [14]. Mi et al. proposed the
use of EMB in combination with regenerative braking in PHEV [15].
In order to further explore the potential of the braking energy
regeneration of electried vehicles, this paper presents a
regenerative braking control algorithm based on a by-wire brake
system. The layout of the adopted brake-by-wire system is
introduced. The regenerative braking control algorithm based on
brake-by-wire system is proposed. The models of the main
components related to the regenerative brake and the frictional brake
of the target electric passenger car are built in MATLAB/Simulink.
The control effects and regeneration efciencies of the proposed
control strategy are simulated in the hard-ware-in-the-loop test
bench. Some simulation results are presented in this article.
Regenerative Braking System Configuration
System Outline
A cooperative regenerative braking system for a front-wheel-
drive electric passenger vehicle equipped with a by-wire brake
system was designed. The overall structure of the regenerative
braking system is shown in Figure 1. An electric control unit,
the BCU (Brake Control Unit) is applied in the regenerative
braking system. The BCU communicates with VCU (Vehicle
Control Unit) and MCU (Motor Control Unit) via CAN bus. The
hydraulic actuator of the regenerative braking system
developed is a by-wire brake system, which is installed
between the master cylinder and the wheel cylinders.
Figure 1. Overall structure of the regenerative braking system.
By-Wire Brake System
As the key component of the proposed regenerative braking
system, the by-wire brake system is adopted as the
electrohydraulic type, which is comprised of a brake pedal
simulator, a high-pressure supply unit, and a hydraulic
pressure modulator, as Figure 2 shows. The brake pedal is
mechanically decoupled from the brake circuits in the
downstream by the brake pedal simulator. The hydraulic
pressure in the brake circuits is actually provided by the
high-pressure supply unit and regulated by the hydraulic
pressure modulator, making the ‘brake-by-wire’ concept
realized. Since the pedal force is decoupled, the driver's
braking intention is detected by the pedal stroke sensor and
sent to BCU. Based on the pedal stroke signal detected and
the real-time operating conditions of the electric powertrain,
BCU controls the actuations of the hydraulic pressure
modulator, regulating the wheel pressure. The modulated
wheel cylinder pressure cooperates with the regenerative
braking torque provided by the electric motor, realizing the
cooperative regeneration based on the by-wire brake system.
Figure 2. Structure of the by-wire brake system.
By-Wire Brake Based Regenrative Braking
Control Algorithm
Braking Force Distribution Strategy
In a conventional vehicle, since the brake pedal is
mechanically connected to the downstream of the brake
circuits, the front-rear brake force distribution (BFD) is not
regulated during braking processes and set as a xed value,
which is determined by parameters of the installed brake
devices, to avoid the brake pedal feel not being affected by the
modulation of hydraulic pressure. However, for an electried
vehicle equipped with a brake-by-wire system, the brake pedal
is mechanically decoupled from the mechanical brake
actuators, and the ideal braking distribution can be achieved by
the by-wire brake system via modulating the braking forces
between the front and the rear wheels. Thus, to achieve high
regeneration efciency and guarantee the brake safety in the
meantime, the front-rear brake force distribution needs to be
reconsidered.
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
Front and Rear Braking Force Allocation
For a front-wheel-drive car, the motor's braking torque can be
only exerted on the front axle. To reach the maximum
regeneration efciency, the front-axle regenerative braking
torque needs to be fully utilized, leading to the BFD being close
to the X axis in Figure 3. But to guarantee the stability during
braking processes, a vehicle should have enough rear braking
force, which is required by the regulation of ECE-R13, as
equation (1) and equation (2) show [16].
(1)
(2)
where, z indicates the brake intensity, φ is the adhesion
coefcient of the road, u is the longitudinal velocity of the
vehicle.
Figure 3. Front and Rear braking force allocation.
However, if the desirable braking performance is expected, the
BFD should be set close to the ideal BFD, which is far from the
x axis. As the ideal braking force allocation required, the front/
rear braking forces can be expressed as [1]:
(3)
(4)
Eliminating the variable φ, the relationship between front-wheel
braking force and rear-wheel braking force can be given as
equation (5), and the ideal BFDs (laden and unladen) are
shown in Figure 3.
(5)
where, Fµ1 is the front-wheel braking force, 2 Fµ2 is the
rear-wheel braking force, G is the gravity of the vehicle, a is the
longitudinal distance from the centre of gravity of the vehicle to
the front axle, b is the longitudinal distance from the centre of
gravity to the rear axle and L is the axle base, hg is the height
of the gravity centre.
Therefore, according to the analysis above, we can see that
there exists a contradiction between regeneration efciency
and brake performance in designing the front/rear BFD for a
front-wheel-drive electric car. The BFD for maximizing
regeneration is required to be far from the one demanded by
maximizing braking performance. For the original strategy, the
BFD is set as a xed value [18], i.e., the front brake force is
linearly correlated with the rear one, as the red dotted line
shown in Figure 3. By doing this, however, the regeneration
capability cannot be fully utilized. To tackle with this issue,
coordinating the regeneration efciency and braking
performance, a BFD for electric car is worthwhile to be
explored.
During the daily operating conditions of an electric vehicle, the
regenerative braking usually needs to be activated under
normal braking procedures, which is corresponding to the
deceleration of the vehicle at 0.1g-0.3g. Once entering the
critical braking situations (deceleration of the vehicle is usually
greater than 0.5g), a good braking performance is required for
a vehicle to ensure a short braking distance. Based on these
practical requirements of a vehicle introduced above, targeting
on a front-wheel-drive electric car, a braking force distribution
strategy is proposed as follows:
1. As shown in Figure 3, under small brake intensity, only
front-wheel regenerative braking force is applied to, and no
friction brake on rear axle is exerted (O to A);
2. To fully guarantee the rear braking force is within the
requirement of the ECE regulation, the rear-wheel friction
force starts to be added and modulated by the by-wire brake
system from point A, before reaching the limitation required
by the ECE regulation;
3. When the deceleration is beyond 0.3g, the designed line
of BFD gets close to the ideal BFD (B to C) gradually, to
make the vehicle obtain a better braking performance under
heavier brake intensity;
4. Once the deceleration reaching 0.6g (C point), the vehicle
enters the emergency driving condition, and the by-wire
brake system will regulate the hydraulic forces in front
and rear wheels, making the designed BFD go complying
with the ideal one, guaranteeing the best dynamic braking
performance of the vehicle.
The designed BFD is illustrated in Figure 3, as the black dotted
line shows. Based on the regenerative braking control strategy
described above, the target electric vehicle can be expected to
achieve the high regeneration efciency under normal
deceleration processes, and ensure the good braking stability
under emergency braking situations.
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
Regenerative and Hydraulic Brakes Distribution
As shown in Figure 4, during deceleration, the overall braking
force of the vehicle is supplied by the regenerative and the
friction blending brakes. The overall brake force is controlled
being consistent with the brake intention of the driver, as
equation (6) shows.
(6)
where, Tb_need is the total braking demand of the vehicle, Treg is
the regenerative braking torque generated by the electric
motor, Tfric indicates the friction braking torque provided by the
mechanical braking system.
Figure 4. Distribution between regenerative brake and hydraulic brake.
To maximize the regeneration efciency, during brake blending,
the regenerative braking torque is fully used on the front axle.
As shown in Figure 4, only regenerative brake is exerted on
front axle at rst. Based on the control algorithm, once the
brake request cannot be met solely by the electric brake, the
rear-wheel hydraulic brake will be supplemented by the by-wire
brake system. And with the increase of the driver's brake
demand, the hydraulic braking force on the front axle will then
be applied gradually. In addition, when the car enters any
critical driving situations, such as the anti-lock braking system
(ABS) or the traction control system (TCS) activates, the
regenerative braking torque will be removed gradually, i.e. only
the hydraulic brake takes over all the braking operation under
emergency braking conditions.
Control Algorithm of the Cooperative
Regenerative Braking
Figure 5 illustrates the control block diagram of the cooperative
regenerative braking. When the driver depresses the brake
pedal, the total brake demand (Tb_need) can be detected via
pressure sensor in the pedal unit, as equation (7) shows.
(7)
where, pm is the hydraulic cylinder pressure of the pedal unit,
μb is the friction coefcient of the brake disc, rf is the radius of
the piston of the front wheel cylinder, Re_ f is the effective
friction radius of the brake disc and β is the real-time front-rear
braking force distribution coefcient.
Based on the brake demand of the vehicle and the designed
braking force distribution strategy, the front-axle braking torque
(Tb_f) and rear-axle braking torque (Tb_r) can be calculated as
follows:
(8)
(9)
As equation (10) shows, according to the SOC of the battery
pack, the speed of the motor, and the torque demand of the
front axle, BCU calculates the command value of the
regenerative braking torque (Treg_cmd) and send it to MCU via
CAN bus.
(10)
where, Treg_lim is the braking torque limit that the electried
powertrain can provide.
Meanwhile, based on the feedback signal of the real value of
the regenerative braking torque, the target values of the
front-wheel cylinder pressure (pf_tgt) and the rear-wheel cylinder
pressure (pr_tgt) can be gured out respectively, as equation
(11) and equation (12) express [2].
(11)
(12)
where, rr is the radius of the piston of the rear wheel cylinder,
Re_r is the effective friction radius of the rear brake disc.
Thus, the by-wire brake system can modulate the front and
rear wheel cylinder pressures to the target values separately
based on the above calculation results. And nally, the
regenerative braking torque provided by the electried
powertrain and the friction braking force generated by the
by-wire brake will meet the total brake request of the vehicle.
System Modeling
In order to verify the feasibility and effectiveness of the
proposed regenerative braking control algorithm, simulation is
required. Before the simulation, appropriate models including
the vehicle, the electric powertrain and the by-wire brake
system need to be built.
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
Figure 5. Cooperative regenerative braking algorithm based on the by-wire brake system.
Vehicle Dynamics
A comprehensive model of vehicle dynamics with eight
degrees of freedom has been built in MATLAB/Simulink and
validated by the present authors [2]. Since the lateral dynamic
control of the vehicle is not involved in the present article, only
the longitudinal motion of the vehicle is modeled. The
longitudinal dynamics of the vehicle during deceleration
processes can be modeled according to the equation [17]:
(13)
where, m is the overall mass of the vehicle, u is the longitudinal
velocity, Fb is the total braking force, f is the coefcient of rolling
resistance, CD is the coefcient of air resistance, A is the
frontal area of the vehicle, ρ is the density of air, and α is the
angle between the road and the horizontal.
The key parameters of the target electric car are shown in
Table 1.
Table 1. Parameters of the target electric vehicle.
Electric Motor
The model of the electric motor is built according to the test
data from an electric motor applied in a commercialized electric
vehicle [2]. The peak torque of the electric drive system is 145
N·m and its nominal power is 29 kW. The efciency map of the
motor in the regenerative braking mode has almost the same
symmetry as that in the driving mode with respect to the axis of
rotational speed. The torque of the electric motor is considered
as a rst-order reaction, which can be expressed as:
(14)
where, Treg,real is the real value of the motor torque detected by
MCU, Treg, cmd is the command value of the motor torque.
By-Wire Brake System
In the by-wire brake system, the hydraulic braking pressure in
downstream of the brake circuit is offered by the high-pressure
supply unit, which is comprised of a high pressure accumulator
and a hydraulic pump-motor. Since the pressure in the high
pressure accumulator phsu always keeps at a considerable high
level, the high-pressure supply unit in the upstream can be
modeled as:
(15)
The wheel cylinder pressure in the downstream of the hydraulic
brake circuit is modulated by the inlet valve and the outlet
valve. The structure of the wheel cylinder is simplied to a
piston and a spring. The wheel cylinder pressure can be
expressed as [19]:
(16)
where, k is the spring stiffness of the wheel cylinder, rw is the
radius of the piston of the wheel cylinder, Cd is the ow
coefcient of the valve, Ac is the cross-sectional area of the
valve opening and ρh is the density of the hydraulic uid.
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
Hardware-in-the-Loop Simulation
To validate and evaluate the control strategy and algorithm of
the cooperative regenerative braking, hard-ware-in-the-loop
(HIL) simulations are carried out.
HIL Simulation Platform
Figure 6 illustrates the conguration of the hardware-in-the-
loop simulation system for the regenerative braking control
system. The entire system is comprised of a real-time
simulation system and a real brake control unit. The real-time
simulation system is the AutoBox from dSPACE. Virtual
models, including vehicle dynamics, the battery, the tyre, and
the electric motor are embedded in the AutoBox. The brake
control unit is a real controller, which is identical to the one
installed on a vehicle.
Figure 6. Cooperative regenerative braking algorithm.
Simulation Scenario Set-Up
The simulations are carried out during scenarios of the normal
deceleration processes. In simulation, the initial braking speed
is set at 30km/h, and the braking pressure at master cylinder is
taken as a ramp input stabilizing at 3MPa, and the road is
assumed to have a dry surface with a high adhesion
coefcient.
Taking the original BFD allocation as a baseline strategy, the
regeneration efciencies of the baseline strategy and the newly
proposed regenerative braking control algorithm are compared
during the normal braking processes.
Simulation Results and Analysis
The simulation results of the two different regenerative braking
control strategies, namely the baseline strategy and the
proposed strategy, are shown in Figure 7 and Figure 8
respectively.
For an electric car with the original regenerative braking control
strategy, as shown in Figure 7, since the front-rear braking
force distribution is set as a xed value, the rear-wheel braking
pressure keeps the same value with the master cylinder
pressure without any modulation during the whole braking
process.
Figure 7. Simulation results of the baseline regenerative braking
control strategy.
Under the proposed regenerative braking control strategy, the
simulation results are shown in Figure 8. At the beginning of
the deceleration procedure, the regenerative braking torque of
the electric motor is exerted gradually on the front axle, and the
front-wheel brake pressure is regulated by the by-wire brake
system based on the proposed braking force allocation, while
the rear-wheel brake is not applied. After 0.35s, the master
cylinder pressure reaches 3MPa, leading to the brake demand
of the vehicle increasing accordingly. The regenerative brake
and the mechanical brake couple in the front axle. In the
meantime, the rear-wheel brake force starts to be applied and
dynamically modulated by the by-wire brake modulator, and its
pressure is much lower than the master cylinder pressure,
which is due to the dened control strategy. At about 2.4s, the
vehicle speed decreases to a relatively low value. Limited by
its full-load characteristics, regenerative braking torque drops
signicantly. Thus, the front hydraulic pressure increases
correspondingly to supplement the vehicle's brake request.
And the front and rear hydraulic pressures are still modulated
by the by-wire brake modulator based on the proposed
distribution strategy. During the whole deceleration, the
regenerative brake and the frictional brake cooperate well and
the braking deceleration changes smoothly, guaranteeing the
braking performance of the vehicle.
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
Figure 8. Simulation results of the proposed regenerative braking
control algorithm.
To evaluate the energy regeneration performance by the
proposed control algorithm during regenerative brake, the
regeneration efciency ηreg is adopted as an evaluation
parameter, which can be expressed as [20]:
(17)
where Ereg is the energy regenerated by the regenerative
braking system, Erecoverable is the maximum value of the
recoverable energy, i.e. the kinetic energy left after subtracting
all the energy that would be dissipated by road drag and air
resistance.
The regenerated energy is expressed by [2]:
(18)
The recoverable energy by
(19)
where t0 is the initial braking time, and t1 is the nal braking
time. U is the output voltage of battery pack. I is the charging
current of battery.
Table 2. HIL simulation results of the regenerative brake under the two
different control algorithms
The regeneration results under normal braking process are
shown in Table 2. According to data, the regeneration efciency
of the original control strategy is 64.94%, while the
regeneration efciency of the proposed control algorithm is
80.10%. The improvement of the regeneration efciency by the
proposed control algorithm based on by-wire brake system is
above 23%.
Conclusions
In order to further explore the potential of the braking energy
regeneration of electried vehicles, a regenerative braking
control algorithm based on a by-wire brake system was
proposed.
The layout of the adopted brake-by-wire system was
introduced. The proposed regenerative braking control
algorithm based on brake-by-wire system was illustrated. The
models of the main components related to the regenerative
brake and the frictional brake of the target electric passenger
car were built in MATLAB/Simulink. The control effects and
regeneration efciencies of the proposed control strategy are
hard-ware-in-the-loop simulated and compared with the original
strategy.
The HIL simulation results show that the proposed regenerative
braking control algorithm is advantageous with respect to the
regeneration efciency. The regeneration efciency of the
original control strategy is 64.94%, while the regeneration
efciency of the proposed control algorithm reaches 80.10%.
The improvement of the regeneration efciency by the
proposed control algorithm based on by-wire brake system is
above 23%.
References
1. Gao, Y., Chen, L., and Ehsani, M., “Investigation of
the Effectiveness of Regenerative Braking for EV and
HEV,” SAE Technical Paper 1999-01-2910, 1999,
doi:10.4271/1999-01-2910.
2. Zhang, J.Z., Lv, C., Gou, J.F. and Kong, D.C., “Cooperative
control of regenerative braking and hydraulic braking of an
electrified passenger car”, Proceedings of the Institution
of Mechanical Engineers, Part D: Journal of Automobile
Engineering 2012; 226(10): 1289-1302.
3. Zhang, J.Z., Chen, X., Zhang, P.J., “Integrated control
of braking energy regeneration and pneumatic anti-lock
braking”, Proceedings of the Institution of Mechanical
Engineers, Part D: Journal of Automobile Engineering 2011;
224(5): 587-610.
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
4. Gao, Y. and Ehsani, M., “Electronic Braking System of EV
And HEV---Integration of Regenerative Braking, Automatic
Braking Force Control and ABS,” SAE Technical Paper
2001-01-2478, 2001, doi:10.4271/2001-01-2478.
5. Zhang, J.Z., Kong, D.C., Lv, C., Chen, X., “Optimization
of control strategy for regenerative braking of electrified
bus equipped with ABS”, Proceedings of the Institution
of Mechanical Engineers, Part D: Journal of Automobile
Engineering 2012; 226(4): 494-506.
6. Jonner, W., Winner, H., Dreilich, L., and Schunck, E.,
“Electrohydraulic Brake System - The First Approach to
Brake-By-Wire Technology,” SAE Technical Paper 960991,
1996, doi:10.4271/960991.
7. Sundar, M. and Plunkett, D., “Brake-by-Wire, Motivation
and Engineering - GM Sequel,” SAE Technical Paper 2006-
01-3194, 2006, doi:10.4271/2006-01-3194.
8. Roberts, M. and Chhaya, T., “An Approach to the Safety
Design and Development of a Brake-by-Wire Control
System,” SAE Technical Paper 2011-01-0212, 2011,
doi:10.4271/2011-01-0212.
9. Nakamura, E., Soga, M., Sakai, A., Otomo, A. et al.,
“Development of Electronically Controlled Brake System for
Hybrid Vehicle,” SAE Technical Paper 2002-01-0300, 2002,
doi:10.4271/2002-01-0300.
10. Ohtani, Y., Innami, T., Obata, T., Yamaguchi, T. et
al., “Development of an Electrically-Driven Intelligent
Brake Unit,” SAE Technical Paper 2011-01-0572, 2011,
doi:10.4271/2011-01-0572.
11. Yeo, H., Koo, C., Jung, W., Kim, D. et al., “Development
of Smart Booster Brake Systems for Regenerative Brake
Cooperative Control,” SAE Technical Paper 2011-01-2356,
2011, doi:10.4271/2011-01-2356.
12. von Albrichsfeld, C. and Karner, J., “Brake System for
Hybrid and Electric Vehicles,” SAE Technical Paper 2009-
01-1217, 2009, doi:10.4271/2009-01-1217.
13. Aoki, Y., Suzuki, K., Nakano, H., Akamine, K. et al.,
“Development of Hydraulic Servo Brake System for
Cooperative Control with Regenerative Brake,” SAE
Technical Paper 2007-01-0868, 2007, doi:10.4271/2007-
01-0868.
14. Ko, J., Lee, G., Ko, S., Ahn, S. et al., “Co-operative Control
of Regenerative Braking using a Front Electronic Wedge
Brake and a Rear Electronic Mechanical Brake Considering
the Road Friction Characteristic,” SAE Technical Paper
2012-01-1798, 2012, doi:10.4271/2012-01-1798.
15. Zhou, Z., Mi, C., Zhang, G., “Integrated control of
electromechanical braking and regenerative braking in
plug-in hybrid electric vehicles,” International Journal of
Vehicle Design 2012; 58(2): 223-239.
16. Gao, Y. and Ehsani, M., “Electronic Braking System of EV
And HEV---Integration of Regenerative Braking, Automatic
Braking Force Control and ABS,” SAE Technical Paper
2001-01-2478, 2001, doi:10.4271/2001-01-2478.
17. Pacejka H., “Tyre and vehicle dynamics,” Elsevier, 2005.
18. Zhang, J., Lv, C., Yue, X., Qiu, M. et al., “Development of
the Electrically-Controlled Regenerative Braking System for
Electrified Passenger Vehicle,” SAE Technical Paper 2013-
01-1463, 2013, doi:10.4271/2013-01-1463.
19. Zhang, J., Lv, C., Yue, X., Li, Y., Yuan, Y., “Study on a
linear relationship between limited pressure difference and
coil current of on/off valve and its influential factors”, ISA
Transactions 2014; 53(1): 150-161.
20. Zhang, J., Lv, C., Qiu, M., Li, Y., Sun, D., “Braking energy
regeneration control of a fuel cell hybrid electric bus”,
Energy Conversion and Management 2013; 76: 1117-1124.
Acknowledgments
The authors would like to thank the Natural Science
Foundation of China [Project no. 51075225] and National High
Tech Project “863” [Project no. 2011AA11A243] for funding this
work.
The Engineering Meetings Board has approved this paper for publication. It has successfully completed SAE’s peer review process under the supervision of the session
organizer. The process requires a minimum of three (3) reviews by industry experts.
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, without the prior written permission of SAE International.
Positions and opinions advanced in this paper are those of the author(s) and not necessarily those of SAE International. The author is solely responsible for the content of the
paper.
ISSN 0148-7191
http://papers.sae.org/2014-01-1791
Downloaded from SAE International by Chen Lv, Monday, March 17, 2014 06:48:17 PM
