dc-dc convertor structu dc convertor structu dc convertor

THE WELDING TECHNOLOGY INFLUENCE ON THE DOUBLE T GIRDER BEAMS BUCKLING (Paper Title)
DC--DC CONVERTOR STRUCTURE
DC
STRUCTURE FOR ENERGY
MANAGEMENT ON (HYBRID)
(HYBRID) ELECTRIC VEHICLE
Assist. Eng. Daniel-Adrian STICEA, PhD1, Prof. Eng. Gheorghe LIVINŢ PhD1,
Assoc. Prof. Eng. Mihai ALBU, PhD1.
1
Technical University of Iasi, Electrical Engineering, Energetics and Applied Informatics Faculty
REZUMAT. Lucrarea prezinta o structura de convertor C.
C.C
C.C
C.- C.
C. multinivel bidirectional pentru gestionarea energiei pe
vehiculele electrice hibride. Structura este alcatuita din mai multe brate de punte si inductori
inductori cuplati
cuplati magnetic. Convertorul
a fost proiectat si realizat practic pentru a interfata sistemul de stocare al energiei, reprezentat prin baterii, la reteaua de
C.C
C.C. a unui stand de vehicul electric hybrid.
Cuvinte cheie: convertor C.C.-C.C., Vehicule Electrice Hibride, managementul energiei.
ABSTRACT. This paper presents a DCDC-DC convertor structure multilevel bidirectional for energy management on hybrid
electric vehicles. The structure consists of several half bridge and magnetic coupled inductor. The convertor
convertor was designed
for interface to the energy storage system, represented by batteries, with DC net of a hybrid electric vehicle stand.
Keywords: DC-DC Convertor, Hybrid Electric Vehicle, energy management.
1. INTRODUCTION
Electrical energy storage systems used in electric
and hybrid vehicles may consist of supercapacitors,
batteries and fuel cells [1]-[5], [8], [9]. In order to
compensate the deficiencies of these sources of energy
storage have been designed hybrid energy storage
systems, such as those presented in [1]-[3], [10]. These
systems combine the advantages of each source of
making a more efficient storage systems. For efficient
energy management, each storage system is connected
to DC bus through a convertor, as in Fig. 1. These
convertors often must be bidirectional to allow both
charging and discharging the accompanying source.
parallel. The series connection is presented in [14]. By
connecting in parallel of the bidirectional switching
cells is obtained a general structure of the convertor as
shown in Fig. 2., where n represents the number of the
half bridge.
Fig. 2. Bidirectional DC-DC Convertor made with 2L-B cells.
Fig. 1. Hybrid energy storage system for Electric Vehicle.
A bidirectional convertor is based on the half bridge
structure integrated in different configurations [2], [3],
[5], [11]. The half bridge structure is known as
bidirectional switching cell (2 Level Bidirectional 2LB) [12]. These cells can be connected in series or in
The power electronic system of the fig. 2. is a
multilevel convertor, at which the benefits of
conversion increase with the number of half bridge is
used. The main advantage of this convertor is the fact
that it can operate both as Buck and Boost mode using
the same structure. Overall system operation, in Buck
or Boost mode, is given by the direction movement of
the global power convertor. Other advantage of the
convertor consist in continuous mode even at low
currents. This is done through a proper command of the
half bridge. Also, for a convertor that uses n parallel
2L-B switching cells, the command corresponding to
each bridge arm must be shifted with TS/n where TS is
_____________________________________________________________________________________
Buletinul
AGIR nr. 4/2012 ● octombrie-decembrie
1
Buletinul AGIR nr. 4/2012 ● octombrie-decembrie
207
NATIONAL
CONFERENCE
OF ELECTRICAL
DRIVES
CNAE
2012 - 2012
_____________________________________________________________________________________
CONFERINŢA
NAŢIONALĂ
DE ACŢIONĂRI
ELECTRICE,
ediţia–XVI,
SUCEAVA
the switching period of the transistors. These gaps allow
obtaining an n+1 voltage levels on the DC – bus [7].
Advantages of bidirectional convertor using 2L-B
cells with magnetically coupled inductors are:
Current through the output capacitor has a
frequency of n*fS (fS / frequency switching) and a ripple
of amplitude equal to 1/n of the corresponding current
convertor with one arm
The absorbed current to the inlet is triangular and
1/n2 amplitude and ripple frequency is also n*fc,
The losses through the inductors are reduced
because their corresponding current will be 1/n.
A disadvantage in achieving DC-DC convertors is
given by the large size of inductance, mainly for the
high power (tens of kilowatts). To reduce the size, the
coupled inductance [6], [7], [13] or forced cooling can
be used, as are presented in [5].
When using for boost convertor with 2L-B cells is
used magnetic coupling for two inductors, according [6]
obtain a low current ripple for each phase (half bridge).
The current ripple decreases, in the same time with the
increase of the coupling factor between the two
inductors. For this variant, can occur, the discontinuous
current mode that brings many disadvantages.
If Coupled-Inductance (CI) is used, as in [7] and
[13] is not possible to appear the discontinous current
mode due to an appropriate control and in the same
time, the converot can functioning in two modes Buck
and Boost. Nevertheless, the current ripple per phase
increase if a magnetic coupled inductor is used.
However, the main advantage brought by a
magnetically coupled inductor in this case is given by
the reduction in expense growth inductor current gauge
on the arm of the bridge (on phase).
2. DC-DC CONVERTOR WITH FOUR HALF
BRIDGE AND MAGNETIC COUPLED
INDUCTOR
DC-DC Convertor modeling.
Modeling of DC – DC convertor with four half
bridge was performed using the Psim 9.0 program.
Energy storage source was modeled by a large capacitor
(5.8 F) in series with a resistance, as in Fig. 3. The
structure of this convertor consists of two convertors
connected in parallel. Each convertor is made of two
arms of the bridge and a magnetically coupled inductor.
To simulate both buck and boost regime, to the DC –
bus of convertor is connected a resistive load or a
constant current source (ISTEP1). In this way it was
tested how the convertor response to a shock load.
Fig. 3. The DC-DC convertor modeling made with four half bridge
and magnetically coupled inductors.
Simulation.
In Fig. 4 is show the simulation data of DC-DC
convertor for buck and boost operating conditions,
including a variety of situations.
Fig. 4. Response converter to the step signal to operate in the buck
and boost modes.
Further, the figure below, to highlight the behavior
of the convertor in all four cases seen in Fig. 4, we
presented detailed waveforms of voltage and current to
the load stage DC / bus, for the overall operation under
boost and buck mode operation.
Fig. 5. Waveforms of current and voltage for the case when the duty
cycle is >50% (Boost operation).
_____________________________________________________________________________________
Buletinul AGIR nr. 4/2012 ● octombrie-decembrie
2
208
Buletinul AGIR nr. 4/2012 ● octombrie-decembrie
THE
WELDING
TECHNOLOGY
INFLUENCE
ON THEMANAGEMENT
DOUBLE T GIRDER
BEAMS BUCKLING
Title)
_____________________________________________________________________________________
DC-DC
CONVERTOR
STRUCTURE
FOR ENERGY
ON (HYBRID)
ELECTRIC (Paper
VEHICLE
Fig. 6. Waveforms of current and voltage for the case when the duty
cycle is equal with 50%.
Fig. 9. The DC-DC bidirectional convertor with two half bridge
(phase) and magnetically coupled inductors.
Fig. 7. Waveforms of current and voltage for the case when the duty
cycle is >50% (Boost operation).
The convertor was designed to interface the energy
storage system represented by 24 Pb batteries, with
(approx. 300 Vdc) to the DC bus of vehicle (approx.
600 Vdc) at which is connected the inverter that supply
the vehicle propulsion induction motor. Converter rated
current is 60 A (30 A on each arm). Due to increased
computing power necessary for the converter control, a
numerical system was designed around an FPGA
system and a dsPIC30F4011 microcontroller. The
numerical system with microcontroller performs
communication of convertor with other system through
CAN (Control Area Network) Network. The
communication between dsPIC and FPGA is achieved
by SPI (Serial Peripheral Interface).
An overview of DC-DC actually made is presented
in Fig. 10.
Fig. 8. Waveforms of current and voltage for the case when the duty
cycle is <50% (Buck operation)
3. DC-DC CONVERTOR WITH TWO HALF
BRIDGE AND MAGNETICALLY
COUPLED INDUCTORS
DC-DC Convertor designed.
The topology of the DC-DC convertor with two
arms and inductor magnetically coupled is presented in
Fig. 9. This convertor connects the battery pack to the
DC bus (of the hybrid electric vehicle bench).
Fig. 10. Overview of DC-DC convertor made practical.
_____________________________________________________________________________________
Buletinul
AGIR nr. 4/2012 ● octombrie-decembrie
3
Buletinul AGIR nr. 4/2012 ● octombrie-decembrie
209
NATIONAL
CONFERENCE
OF ELECTRICAL
DRIVES
CNAE
2012 - 2012
_____________________________________________________________________________________
CONFERINŢA
NAŢIONALĂ
DE ACŢIONĂRI
ELECTRICE,
ediţia–XVI,
SUCEAVA
Experimental results.
In Fig. 11 are presented the waveforms of currents
through the two arms of the converter (CH1 and CH2)
and the waveforms of the common mode current
(CH1+CH2) and differential mode (CH1-CH2), for
operation of the converter under boost regime. The
experimental data presented in this figure were
tobtained by connecting 4 batteries of 12 V to the input
of the DC-DC converter and an open loop operation of
the convertor. Load connected to the DC-Link is only
resistive. Duty cycle of PWM signal for control the two
arms of a bridge to the situation presented in Fig. 5 is
about 25%. This case corresponds to the highest
common mode ripple current (i1+i2, where i1, i2 are the
currents through the two arms of the bridge).
Fig. 12. The common mode current and differential mode current
for boost regime to a duty cycle < 50% of PWM signal.
Fig. 11. The current waveforms for the boost regime of convertor.
In Fig. 12 and 13 can be seen the waveforms of
common mode current (CH1) and differential mode
current (CH2) for values of the duty cycle of the PWM
signal near to 50%. Also, it can be see the necessity to
implement a control loop differential mode current (i1i2) to eliminate the imbalances that may appear between
the two arms of the convertor. These imbalances are
given by the DC component of the waveform
corresponding to a differential current.
Fig. 13. The common mode current and differential mode current
for boost regime to a duty cycle > 50% of PWM signal.
4. CONCLUSIONS
The DC-DC convertors made with half bridge
structure, connected in parallel, increase the conversion
performance at the expense of computing power
necessary to control the convertor. The absorbed
current ripple from the energy storage system is
reduced. Reducing gauge inducers used in DC-DC
convertors can be achieved by using magnetically
coupled inductances. The disadvantage in this case gave
rise ripple current is given by the arm (phase) and thus
the transistor, which currently is not problem.
Designing a convertor to work in around 50% of the
Pulse Width Modulation (PWM) signal provides the
advantage of the current ripple drawn from the energy
storage system approximately zero.
_____________________________________________________________________________________
Buletinul AGIR nr. 4/2012 ● octombrie-decembrie
4
210
Buletinul AGIR nr. 4/2012 ● octombrie-decembrie
THE
WELDING
TECHNOLOGY
INFLUENCE
ON THEMANAGEMENT
DOUBLE T GIRDER
BEAMS BUCKLING
Title)
_____________________________________________________________________________________
DC-DC
CONVERTOR
STRUCTURE
FOR ENERGY
ON (HYBRID)
ELECTRIC (Paper
VEHICLE
BIBLIOGRAPHY
[1] M.B. Camara, H. Gualous, F. Gustin, A. Berthon, Control
strategy of Hybrid sources for Transport applications using
supercapacitors and batteries, Power Electronics and Motion
Control Conference, Volume 1, pp. 1 – 5, ( 2006).
[2] M. B. Camara, H. Gualous, F. Gustin, A. Berthon, B. Dakyo,
DC/DC Converter Design for Supercapacitor and Battery
Power Management in Hybrid Vehicle Applications—
Polynomial Control Strategy, IEEE Transactions on Industrial
Electronics, Volume 57, No. 2, pp. 587 – 597, (2010).
[3] J. Caou and A. Emadi, A New Battery/Ultra-Capacitor Hybrid
Energy Storage System for Electric, Hybrid and Plug-in Hybrid
Electric Vehicles, Vehicle Power and Propulsion Conference,
pp. 941 – 946, (2009).
[4] Kyoungmin Son, Sejin Noh, Kyoungmin Kwon, Jaeho Choi,
Eun-Kyu Lee, Line Voltage Regulation of Urban Transit
Systems Using Supercapacitors, Power Electronics and Motion
Control Conference, (2009).
[5] D. P. Urciuoli and C. W. Tipton, Development of a 90 kW BiDirectional DC-DC Converter for Power Dense Applications,
Applied Power Electronics Conference and Exposition, (2006).
[6] J. Gallagher, Designing Coupled Inductors, Field Application
Engineer, Power Division, Pulse, San Diego, Power Electronics
Technology, January 2006.
[7] A. Fratta, G. Griffero, S Nieddu, G. M. Pellegrino, F. Villata,
Inductive Three-Level V.- Supplied Conversion Cell by New
Hybrid Coupling Reactor Family, Industry Applications
Conference, Volume 4, pp. 2378 – 2385, (2002).
[8] G. Calderon-Lopez, A. J. Forsyth and D. R. Nuttall, Design
and Performance Evaluation of a 1O-kW Interleaved Boost
Converter for a Fuel Cell Electric Vehicle, Power Electronics
and Motion Control Conference, Volume 2, pp. 1 – 5, ( 2006).
[9] Sharanya Jaganathan, Wenzhong Gao, Battery Charging
Power Electronics Converter and Control for Plug-in Hybrid
Electric Vehicle, Vehicle Power and Propulsion Conference, pp.
440 – 447, (2009).
[10] Xiaofei Liu, Qianfan Zhang, Chunbo Zhu, Design of Battery
and Ultracapacitor Multiple Energy Storage in Hybrid Electric
Vehicle, Vehicle Power and Propulsion Conference, pp. 1395 –
1398, (2009).
[11] Jian-ming HU, Yuan-rui CHEN, Zi-juan YANG, Study and
Simulation of One Bi-directional DC/DC Converter in Hybrid
Electric Vehicle, Power Electronics Systems and Applications,
pp. 1 – 4, (2009).
[12] Dan Floricau, Elena Floricau, and Guillaume Gateau, New
Multilevel Converters With Coupled Inductors: Properties and
Control, IEEE Transactions on Industrial Electronics, Volume
58, No. 12, pp. 5344 – 5351, (2011).
[13] A. Fratta, P. Casasso, G. Griffero, P. Guglielmi, S. Nieddu,
G.M. Pellegrino, New design concepts and realisation of hybrid
DC/DC coupling reactors for light EVs, Industrial Electronics
Society, IECON '03, Volume 3, pp. 2877 – 2882, (2003)
[14] Petar J. Grbovic, Philippe Delarue, Philippe Le Moigne and
Patrick Bartholomeus, A bi-directional three-level dc-dc
converter for the ultra-capacitor applications, IEEE Trans.
Industrial Electronics, Vol 57. No.10, pp. 3415-3430, (Oct.
2010).
About the authors
Assist. Eng. Daniel-Adrian STICEA, PhD
Technical University “Gheorghe Asachi” from Iaşi, Electrical Engineering, Energetics and Applied Informatics Faculty
email:[email protected]
Graduate of the Electrical Engineering Faculty of Tehchnical University “Gheorghe Asachi” from Iaşi in 2007.
Prof. Eng. Gheorghe LIVINŢ, PhD.
Technical University “Gheorghe Asachi” from Iaşi, Electrical Engineering, Energetics and Applied Informatics Faculty
email:[email protected]
He is graduated at the Gheorghe Asachi Technical University of Iasi, Electrotechnical Faculty, and electromechanical
specialization in 1972. After graduation he worked directly in higher education as assistant, and then as lecturer, associated
professor. Since 1996 working as professor at the disciplines: The systems theory, the identification and modeling of
systems. Also since 2004 he is supervisor of doctoral theses in electrical engineering. He is author of over 150 articles and
15 patents. His research topics are control of electrical drives and industrial processes, hybrid electrical vehicles.
Assoc. Prof. Eng. Mihai ALBU, PhD.
Technical University “Gheorghe Asachi” from Iaşi, Electrical Engineering, Energetics and Applied Informatics Faculty
email:[email protected]
_____________________________________________________________________________________
Buletinul
AGIR nr. 4/2012 ● octombrie-decembrie
5
Buletinul AGIR nr. 4/2012 ● octombrie-decembrie
211