 Open Access
 Total Downloads : 556
 Authors : Narendra Bavisetti, Praveen Mannam, Satyanarayana V
 Paper ID : IJERTV2IS3229
 Volume & Issue : Volume 02, Issue 03 (March 2013)
 Published (First Online): 20032013
 ISSN (Online) : 22780181
 Publisher Name : IJERT
 License: This work is licensed under a Creative Commons Attribution 4.0 International License
Analysis Of Coupled Inductor Type Power DCDC Boostconverter With Synchronized PWM Control
Narendra Bavisetti, Praveen Mannam, Satyanarayana V,
Assistant Professor, Ramachandra College of Engineering, Eluru, W.G (Dt), Andhra Pradesh Assistant Professor, KKR & KSR Institute of Technology and Science, Guntur (Dt), Andhra Pradesh Associate Professor, Ramachandra College of Engineering, Eluru, W.G (Dt), Andhra Pradesh
Abstract Bidirectional DC – DC converters play an important role in applications where conversion of DC DC is involved. These applications include hybrid electric vehicles, switching mode power supplies, battery charges and uninterruptible power supplies. Many converter topologies are proposed and are available. All these converters utilize energy storage devices for transfer of energy between source and load. The proposed concept makes use of same principles for transfer of energy using a coupled inductor as one of the commutating element, performance of the converter is analyzed with the help synchronized pulse width modulation control scheme. For this purpose a bidirectional DC DC converter available in reference [1] is considered, for which statespace model is formulated. The model thus formulated is simulated with the help of MATLAB / Simulink and SimpowersystemsBlockset for different values of conversion ratios and when supplying load power varying from 50W to 200W for different values of Capacitor to Inductor Factor.
Keywords Bi directional DC DC Converters, Stored Energy, Energy Factor, Converter Time Constant, Damping Time Constant.

INTRODUCTION
Bi directional DC DC Converters are useful in applications where power transfer takes place in either direction i.e power transfer between two DC DC sources. These converters are widely used in hybrid electric vehicles, photovoltaic hybrid power Systems, Fuel cell hybrid power systems, uninterruptible power systems and battery charges. Many bi directional DC DC Converter topologies are proposed in literature out of the available models, bi – directional DC DC flyback converters are found to be simple in structure and easy in control. It is observed that the switches used in the switches used in these converters subjected to high voltage stress due to leakage energy released by transformer during energy transfer phase. For minimization of voltage stress of converter switches due this leakage energy release by transformer literature suggests energy regeneration techniques. These techniques suggest that the leakage inductor energy is recycled by clamping the voltage stress
on the converter switches. In some of the literature isolated bi directional DC DC converters are proposed, these converter technologies includes half bridge, full bridge types. These technologies make use of adjustable turns transformers as a result of that these converters provide high step up and step down voltage gains. For non isolated applications non isolated bidirectional DC DC Converters are suggested. These converters include topologies like buck / boost, multilevel level converters, Three level Converters, Sepic / Zeta, Switched capacitor and coupled inductors. Three Level and Multi Level converters suffer with low step up and step down voltage gains. Sepic / Zeta converters uses two stages for power conversion, this results in more losses as a result conversion efficiency decreases. Multi level type converters make use of magnetic less converter concept, and require more number of switches for energy conversion. This makes this topology with complicated structure and control circuit. If more step up and step down voltage gains are required the number switches are to be increased. This makes the control more complicated. The switched capacitor and coupled inductor converters can provide higher step up and step down voltage gains. And the voltages appearing across switches used in these topologies can be made minimum.
Figure 1: Circuit Diagram of Conventional Bi directional DC DC Converter.
Figure 1 Show conventional DC DC converter with two switches S1 and S2. A modification is made to the above circuit such that the inductor is replaced with a coupled inductor and one more switch is added. New
configuration is shown in figure 2. The preceding sections will discuss the modeling issues involved, results obtained.
W vL1iL1 .dt
But from equation (3) substitute value of iL1
W
Vs vL1 1 k L
t1 .dt
Energy stored by inductor by the end of mode1 is
V
V
t1
s
s
W Vs
t1 .dt
0 1 k L V 2t 2
2 1 k
2 1 k
L
L
s 1
Total energy stored by the inductors is
W
W
V 2t 2
Figure 2: Proposed DC DC Converter model diagram
s 1
L
J (4)
working as boost converter.

DC DC CONVERTERS
Coupled inductor type DCDC converter circuits make use of coupled inductors for energy transfer during conduction period. In most of the configurations these inductors are charged by connecting in parallel during
1 k L 1
During Mode 2 load connected to the source as a result the inductors are connected in series and will get discharged, the energy thus stored by these inductors will be transferred to the capacitor, there by the capacitor starts charging.
During this mode
iL1 iL2 iL And
charging mode and discharged by connecting in series.
Good literature is available for such applications,
vL1

vL2
Vs
Vc
it has been prove that this kind of converters offer wide range of conversion ratios.
Consider the bidirectional DCDC converter
diL 21 M L V dt s
Vc
topology given in [1] for analysis purposes. During mode 1 operation of the converter Inductors and capacitor are
diL
dt
Vs
21 M L
Vc
21 M L
allowed to charge and discharge that means inductors will get charged and capacitor gets discharged.
Voltage across capacitor is given by
Amount energy stored by the inductor is
W pt .dt
1
1
(2)
vc
C iL dt
During mode 1 of operation current flowing through the inductor is given by
dvc
dt
1 i C L
diL1 t diL 2 t Vs
Take vc x1 and iL x2
dt dt
1 k L 1
t1 V
x1 x2
C

v

v
iL1
dt
1 1
s
s
0 1 k L
x2 x
2 1 M L
21 M L s
1
1
V
V
i s t
(3)
State variable model of the system is given by
Where
L1 1 k L 1
0 1 0
Instantaneous power is
pt
x1
C x1 1
v (5)
1
x
s
Applied voltage is Vs
x2
21 M L
0 2
21 M L
Inductance of the coils L1 L2 L
Coefficient of coupling is k
Energy stored by inductor is W
Take vc as control variable. Then
Instantaneous power is given by
pt v
L1iL1
y x1
Where y is the output variable
Substitute values of vL1 and iL1 in equation (2)
From equation (4) it is clear that amount of enegy stored by an inductor is controlled by controlling the charging and discharging periods of the converter. The magnitude of output voltage is controlled by proper selection of ON and OFF periods of converter circuit. There by the equations

and (5) are equally applicable to buck, boost and buck boost configurations.


ANLYSIS OF BOOST CONVERTER
Model proposed in [1] is considered for analysis, Model is simulated by taking L1 = L2 = 15.5×106H, M = 1×106H, C = 330 X 106F, V1 = 14V, I1 = 10A, P0 = 200W, T =
20ÂµSec, for which Energy Factor is found to be 104.53mJ, CIR = 176.4 considering the system as loss less = 23.55ÂµSec, and d = 4154.22ÂµSec.
It is observed that d>> , the system response is under damped. And the damped oscillations will die out in a period of 4d.
An attempt is made to reduce the damped oscillations
that produced during the transient response by varying the factor like CIR, P0 and Energy factor, by doing so the magnitudes of and d are varied.
Proposed converter circuit is simulated using MATLAB / SIMULINK, SimpowersystemsBlockset for different values of CIF, the response characteristic is observed for connected loads varied from 50watts 200watts. Converter parameters load Voltage, Load Current, Efficiency, Current through inductors, Voltage across switches and current through the switches are tabulated shown in figures 4 9 for k = 0.6, P0 = 200watts, CIR = 0.25.
Figure 3: Simulink Model diagram for the proposed
model.

RESULTS
L1 and L2 are found to be 0.1082H and efficiency of the system is 93.3%. Load Voltage is equal to 54.7Volts.
Figure 4: Efficiency characteristic of proposed converter with time for k = 0.6, P0 = 200watts.
Figure 5: Load Voltage and Load Current characteristic of proposed converter with time for k = 0.6, P0 = 200watts.
Figure 6: Current through L1 and L2 for the proposed converter with time for k = 0.6, P0 = 200watts.
Figure 7: Current through S1 and Voltage across S1 for proposed converterwith time for k = 0.6, P0 = 200watts.
Figure 8: Current through S2 and Voltage across S2 for proposed converterwith time for k = 0.6, P0 = 200watts.
Figure 9: Current through S3 and Voltage across S3 for proposed converterwith time for k = 0.6, P0 = 200watts.
The proposed converter is simulated for three cases k = 0.4, 0.5 and 0.6 for output powers 50Watts, 100Watts, 150Watts and 200Watts. Characteristics and circuit parameters are tabulated in Table 1 to table 6.
Table 1: Magnitudes of different parameters for k = 0.6
and C = 330ÂµF
CIF = 0.25, V1 = 14V
P0 in Watts
Lin Henry
V0 in Volts
I0 in Amps
%
50
1.7306
55.66
0.888
94.95
100
0.4327
55.34
1.766
94.45
150
0.1923
55.02
2.63
93.84
200
0.1082
54.7
3.48
93.28
Table 2: Magnitudes of different parameters for k = 0.5
and C = 330ÂµF
CIF = 0.25, V1 = 14V
P0 in Watts
Lin Henry
V0 in Volts
I0 in Amps
%
50
0.5477
41.73
1.18
94.21
100
0.1369
41.48
2.35
93.61
150
0.0609
41.23
3.50
93.00
200
0.0342
40.97
4.64
92.40
Table 3: Magnitudes of different parameters for k = 0.4
and C = 330ÂµF
CIF = 0.25, V1 = 14V
P0 in Watts
Lin Henry
V0 in Volts
I0 in Amps
%
50
0.2004
32.45
1.52
93.69
100
0.0501
32.24
3.02
93.05
150
0.0223
32.05
4.50
92.39
200
0.0125
31.82
5.97
91.75
Table 4: Magnitudes of different parameters for k = 0.6
and C = 330ÂµF
CIF = 25, V1 = 14V
P0 in Watts
Lin Henry
V0 in Volts
I0 in Amps
%
50
0.0173
55.66
0.888
94.97
100
0.0043
55.34
1.766
94.45
150
0.0019
55.02
2.63
93.84
200
0.0011
54.7
3.48
93.28
Table 5: Magnitudes of different parameters for k = 0.5
CIF = 25, V1 = 14V
P0 in Watts
Lin Henry
V0 in Volts
I0 in Amps
%
50
0.0055
41.73
1.18
94.21
100
0.0014
41.48
2.35
93.61
150
0.0007
41.23
3.50
93.00
200
0.0003
40.97
4.64
92.40
CIF = 25, V1 = 14V
P0 in Watts
Lin Henry
V0 in Volts
I0 in Amps
%
50
0.0055
41.73
1.18
94.21
100
0.0014
41.48
2.35
93.61
150
0.0007
41.23
3.50
93.00
200
0.0003
40.97
4.64
92.40
and C = 330ÂµF
Table 6: Magnitudes of different parameters for k = 0.4
and C = 330ÂµF
CIF = 25, V1 = 14V
P0 in Watts
Lin Henry
V0 in Volts
I0 in Amps
%
50
0.002
32.45
1.52
93.69
100
0.0005
32.24
3.02
93.05
150
0.0002
32.05
4.50
92.39
200
0.0001
31.82
5.97
91.75

CONCLUSION
It has been observed that DCDC Boost Converter designed using synchronised PWM control with variation of Capacitor to Inductor Ratio and Energy factor the settling time of the system is varying, efficiency of the system remains constant and varies in between 91% to 95%. Efficiency of the system is decreasing with increase in load. The ripple cotent in the output voltage is low.
REFERENCES

LungSheng Yang and Tsorng Juu Liang, Analysis and Implementation of Novel Bidirectional DCDC Converter, IEEE Trans.Ind. Electron. , vol. 59, no. 1, pp. 422434, Jan. 2012.

M. B. Camara, H. Gualous, F. Gustin, A. Berthon, and
B. Dakyo, DC/DCconverter design for supercapacitor and battery power management inhybrid vehicle applications Polynomial control strategy, IEEE Trans.Ind.Electron. , vol. 57, no. 2, pp. 587597, Feb. 2010.

T. Bhattacharya, V. S. Giri, K. Mathew, and L. Umanand, Multiphasebidirectional flyback converter topology for hybrid electric vehicles,IEEE Trans. Ind. Electron. , vol. 56, no. 1, pp. 7884, Jan. 2009.

Z. Amjadi and S. S. Williamson, A novel control technique for aswitchedcapacitorconverterbased hybrid electric vehicle energy storage system, IEEE Trans. Ind. Electron., vol. 57, no. 3, pp. 926934,Mar. 2010.

F. Z. Peng, F. Zhang, and Z. Qian, A magneticless dcdc converter fordualvoltage automotive systems, IEEE Trans. Ind. Appl., vol. 39, no. 2,pp. 511518, Mar./Apr. 2003.

L. Schuch, C. Rech, H. L. Hey, H. A. Grundling, H. Pinheiro, andJ. R. Pinheiro, Analysis and design of a new highefficiency bidirectionalintegrated ZVT PWM converter for DCbus and batterybank interface,IEEE Trans. Ind. Appl., vol. 42, no. 5, pp. 13211332, Sep./Oct. 2006.

X. Zhu, X. Li, G. Shen, and D. Xu, Design of the dynamic powercompensation for PEMFC distributed power system, IEEE Trans. Ind.Electron. , vol. 57, no. 6, pp. 19351944, Jun. 2010.

G. Ma, W. Qu, G. Yu, Y. Liu, N. Liang, and W. Li, A zerovoltageswitching bidirectional dcdc converter with state analysis and softswitchingoriented design consideration, IEEE Trans. Ind. Electron. ,vol. 56, no. 6, pp. 21742184, Jun. 2009.

F. Z. Peng, H. Li, G. J. Su, and J. S. Lawler, A new ZVS bidirectionaldcdc converter for fuel cell and battery application, IEEE Trans. PowerElectron. , vol. 19, no. 1, pp. 5465, Jan. 2004.

K. Jin, M. Yang, X. Ruan, and M. Xu, Threelevel bidirectional converterfor fuelcell/battery hybrid power system, IEEE Trans. Ind. Electron.,vol. 57, no. 6, pp. 19761986, Jun. 2010. [11]R.Gules,J.D.P.Pacheco,H.L.Hey,andJ.Imhoff,Amaxi mumpower point tracking system with parallel connection for PV standaloneapplications, IEEE Trans. Ind. Electron. , vol. 55, no. 7, pp. 26742683,Jul. 2008.

Z. Liao and X. Ruan, A novel power management control strategy forstandalone photovoltaic power system, in Proc. IEEE IPEMC, 2009,pp. 445449.

S. Inoue and H. Akagi, A bidirectional dcdc converter for an energystorage system with galvanic isolation, IEEE Trans. Power Electron.,vol. 22, no. 6, pp. 22992306, Nov. 2007.

L. R. Chen, N. Y. Chu, C. S. Wang, and R. H. Liang,
Design of a reflexbased bidirectional converter with the energy recovery function, IEEETrans. Ind. Electron., vol. 55, no. 8, pp. 30223029, Aug. 2008.

S. Y. Lee, G. Pfaelzer, and J. D. Wyk, Comparison of different designs ofa 42V/14V dc/dc converter regarding losses and thermal aspects, IEEETrans. Ind. Appl. , vol. 43, no. 2, pp. 520530, Mar./Apr. 2007.

K. Venkatesan, Current mode controlled bidirectional flyback converter,in Proc. IEEE Power Electron. Spec. Conf., 1989, pp. 835842.

T. Qian and B. Lehman, Coupled inputseries and outputparallel dual interleaved flyback converter for high input voltage application, IEEETrans. Power Electron., vol. 23, no. 1, pp. 8895, Jan. 2008.

G. Chen, Y. S. Lee, S. Y. R. Hui, D. Xu, and Y. Wang, Actively clampedbidirectional flyback converter, IEEE Trans. Ind. Electron. , vol. 47, no. 4,pp. 770779, Aug. 2000.

F. Zhang and Y. Yan, Novel forwardflyback hybrid bidirectional dcdcconverter, IEEE Trans. Ind. Electron., vol. 56, no. 5, pp. 15781584,May 2009.

H. Li, F. Z. Peng, and J. S. Lawler, A natural ZVS mediumpowerbidirectional dcdc converter with minimum number of devices, IEEETrans. Ind. Appl. , vol. 39, no. 2, pp. 525535, Mar. 2003.

B. R. Lin, C. L. Huang, and Y. E. Lee, Asymmetrical pulsewidth modulation bidirectional dcdc converter, IET Power Electron., vol. 1, no. 3,pp. 336347, Sep. 2008.

Y. Xie, J. Sun, and J. S. Freudenberg, Power flow characterization of abidirectional galvanically isolated highpower dc/dc converter over a wideoperating range, IEEE Trans. Power Electron. , vol. 25, no. 1, pp. 54 66,Jan. 2010.

I. D. Kim, S. H. Paeng, J. W. Ahn, E. C. Nho, and J. S. Ko, Newbidirectional ZVS PWM sepic/zeta dcdc converter, inProc. IEEE ISIE,2007, pp. 555560.

Y. S. Lee and Y. Y. Chiu, Zerocurrentswitching switchedcapacitorbidirectional dcdc converter, Proc. Inst. Elect. Eng.Elect. PowerAppl., vol. 152, no. 6, pp. 15251530, Nov. 2005.

R. J. Wai and R. Y. Duan, Highefficiency bidirectional converter forpower sources with great voltage diversity, IEEE Trans. Power Electron. ,vol. 22, no. 5, pp. 19861996, Sep. 2007.

L. S. Yang, T. J. Liang, and J. F. Chen,
Transformerless dcdc converterswith high stepup voltage gain, IEEE Trans. Ind. Electron. , vol. 56, no. 8,pp. 31443152, Aug. 2009.