International Journal of Recent Advances in Engineering & Technology (IJRAET)
INVESTIGATION OF TWO PHASE BRIDGELESS INTERLEAVED BOOST CONVERTER FOR POWER FACTOR CORRECTION
1V.Nithin, 2P.Siva Priya, 3N.Siva Sumanth, 4Dr.R.Seyezhai & 5K.Vigneshwar, Department of EEE, SSN College of Engineering, Chennai.
Email : 1[email protected], 2[email protected], 3[email protected],
4[email protected] & 5[email protected]
Abstract - Hybrid Electric Vehicles (HEV) usually need power conditioning, typically rectification which uses non linear devices, that produces a non-sinusoidal line current due to their non- linear input characteristics. The reduction of line current harmonics for enhancing the efficiency is Power Factor Correction. For active power factor topologies, there exist bridged and bridgeless power converter circuits. This paper focuses on a bridgeless Interleaved Boost Converter (IBC) for shaping the line current waveform. Moreover, this paper discusses about various boost converter topologies which are designed and simulated using MATLAB - SIMULINK for active power factor correction. Performance parameters such as the Total Harmonic Distortion (THD) in the line current, input power factor and displacement factor are investigated for all the topologies. On comparison, this paper insists on the fact that Bridgeless Interleaved Boost Converter has higher input power factor and lower harmonics in the line current which is verified through simulation.
Index Terms – AC – DC Boost Converters, Bridgeless Interleaved Boost Converter, HEV, Power Factor Correction.
I. INTRODUCTION
The supply current in Hybrid Electric Vehicles (HEV) has high amount of harmonics which are due to power conditioning circuits and other non-linear loads. They have many adverse effects in the system. They need to be rectified and reduced to maintain unity power factor which otherwise leads to power losses. As a result there is a need for reduction in line current harmonics or Power Factor Correction-PFC.
Power factor correction can be done in two ways (i) Passive Power factor Correction
(ii) Active Power Factor Correction.
Passive devices like capacitor banks are used in Passive power factor correction. By using passive power factor correction the vehicle becomes bulkier and also becomes
uneconomical. Therefore active power factor correction is implemented using power electronic devices to improve the efficiency of the PFC stage by lowering the conduction and switching losses. The active power factor correction is further classified into high frequency active PFC and low frequency active PFC. Among these PFCs better power factor is obtained by using high frequency active PFC circuit[1][2].
A Bridgeless Inter leaved Boost Power factor correction circuit is designed and simulated using MATLAB – SIMULINK. The results obtained are compared with the simulation results of the other topologies that are reported in the literature[3].
II. OPERATION OF TWO PHASE BRIDGELESS INTERLEAVED BOOST
CONVERTER FOR POWER FACTOR CORRECTION
Fig.1 Circuit Diagram of Two Phase Bridgeless Interleaved Boost Power Factor Conversion Circuit
To analyze the circuit operation, it has been separated into two half cycles. During the “positive” half cycle, when AC input voltage goes positive, Q1 turns on and current flows through L1, Q1 and continues through Q2 and then L2 to store energy in L1 and L2. When Q1 turns off, energy stored in L1 and L2 will be released as current flows through D1, through the Load and returns through the body diode of Q2 back to the mains.[4] . The same cycle happens for Q3, but with a 180° phase delay. During the “negative” half cycle, Q2 and Q4 turn on, current flows through the inductors L2 and L1 (L4 and L3 for the interleaved one). When the MOSFETs are off, energy is released as current flows through D2 (and D4), through load and back to the main through the body diode of Q1 (and Q3)[5]-[8].
DESIGN EQUATIONS:
The duty ratio (D) of a typical boost converter is given by[9]:
D =
Vout−VinVout
(1)
Vout - Output Voltage, Vin - Input Voltage.
The inductor shown in Fig.1 can be designed using the expression:
L =
Vin x DIripple x f
(2)
Where L – Inductance, f - switching frequency and Iripple - inductor current ripple.
The value of capacitance (C) [9] is given by the expression:
C =
Vout x Df x ΔV x R
(3)
Where ΔV - Output voltage rippleIII. ANALYSIS OF TOPOLOGIES FOR POWER FACTOR CORRECTION
A. Conventional Boost Power Factor Correction Circuit:
Fig.2 Conventional Boost Power Factor Correction Circuit
The Conventional Boost Power Factor Correction Circuit [10] is shown in Fig.2
Design Specifications:
Table I Simulation Parameters Of Conventional Boost Power Factor Correction Circuit
Input voltage 20 V
Supply frequency 50 Hz
L 131.575 µH
R 52.63 Ω
C 850 ΩF
Switching frequency 25 kHz Analysis:
1) The amount of Total Harmonic Distortion in Supply current was observed to be 93.83%.
2) Power Factor of this topology with the mentioned design specifications was found out to be 0.68.
B. Bridgeless Boost Power Factor Correction Circuit:
Fig.3 Bridgeless Boost Power Factor Correction Circuit The Bridgeless Boost Power Factor Correction Circuit [10] is shown in Fig.3.
Design Specifications:
TABLE II. Simulation Parameters of Bridgeless Boost Power Factor Correction Circuit
gm DS
m km a k
a m k
m km a k gm DS
gm DSm a k m a k
Input voltage 20 V
Supply frequency 50 Hz
L 131.575 µH
R 52.63 Ω
C 850 µH
Analysis:
1) The amount of Total Harmonic Distortion in Supply current was observed to be 82.02%.
2) Power Factor of this topology with the mentioned design specifications was found out to be 0.76.
C. Interleaved Boost Power Factor Correction Circuit:
Fig.4 Interleaved Boost Power Factor Correction Circuit The Interleaved Boost Power Factor Correction Circuit [10] is shown in Fig.4.
Design Specifications:
Table III: Simulation Parameters for Interleaved Boost Power Factor Correction Circuit
Input Supply 20 V
Supply frequency 50 Hz
R1,R2 25milli ohms
L1,L2 667 µh
R 52.63 Ω
C 850 µf
Switching Frequency 25 KHz
Analysis:
1) The amount of Total Harmonic Distortion in Supply current was observed to be 72.65%.
2) Power Factor of this topology with the mentioned design specifications was found out to be 0.799.
D. Bridgeless Interleaved Boost Power Factor Correction Circuit:
Fig.5 Bridgeless Interleaved Boost Power Factor Correction Circuit
The Bridgeless Interleaved Boost PFC Circuit[10] is shown in Fig.5.
Design Specifications:
Table IV - Simulation Parameters Of Bridgeless Interleaved Boost Power Factor Correction Circuit
Input Supply 20 V
Supply frequency 50 Hz
L1,L2,L3,L4 667 µh
C 850 µf
R 52.63 Ω
Switching Frequency 25 kHz Analysis:
1) The amount of Total Harmonic Distortion in Supply current was observed to be 43.60%.
2) Power Factor of this topology with the mentioned design specifications was found out to be 0.8412.
L1
L2
L3
L4
R
gm DS
gm DS makmak
mak mak
C
gm DS gm DS
Fig.6 Comparison of Power Factors of Various Boost Converter Topologies
Fig.7 Comparison of THD contents of Various Boost Converter Topologies
From the above analysis, it is observed that the bridgeless Interleaved Boost Converter gives higher power factor with reduced THD when compared with the conventional and Bridgeless PFC’s. The results are shown in Table: V.
Table V – Comparison of Performance Parameters of Various Power Factor Conversion Circuits
TYPE L(H) THD PF
Conventional Bridge PFC
131.575µH 94% 0.688 Conventional
Bridge PFC
667µH 69.04% 0.79 Bridgeless PFC 131.575µH 82.02% 0.76 Bridgeless PFC 667µH 63.53% 0.7746
Bridge Interleaved PFC
667µH 72.65% 0.79910 Bridgeless
Interleaved PFC
667µH 43.60% 0.8412
IV. SIMULATION RESULTS
In practical applications of active power factor correction, the input AC voltage is first rectified and then boosted using a converter circuit. Bridged and Bridgeless types of converters are simulated using MATLAB – SIMULINK and the supply current and
Fig.8 Supply Current and Supply Voltage waveforms for Conventional Boost Power Factor conversion circuit
Fig.9 Supply Current and Supply Voltage waveforms for Bridgeless Boost Power Factor Conversion circuit
Fig.10 Supply Current and Supply Voltage Waveforms for Interleaved Boost Power Factor Conversion circuit
Fig.11 Supply Current and Supply Voltage Waveforms for Bridgeless Interleaved Boost Power Factor
Converter
V. CONCLUSION
A bridgeless Interleaved Boost Converter is designed and simulated in this paper. A comparative study of the Conventional boost, Bridgeless Boost, Interleaved boost and Bridgeless Interleaved Boost topologies for active power factor Correction in AC-DC converters has been carried out in this paper. From the results, it is found that the Bridgeless Interleaved Boost Converter topology for active power factor correction is a promising topology as it affords improved Total Harmonic Distortion and power factor closer to unity.
VI. REFERENCES
[1] Ghanekar ,“Active Power Factor Correction using switched Regulators,” Sinhgad Academy of Engineering, Kondhwa (Bk), Pune-41104, India.
[2] D. Marsh,“Active Power Factor Correction”, EDN Magazine, Jan. 2000, pp. 31-41
[3] Kurma Sai Mallika,“Topological Issues In Single Phase Power Factor Correction,”
Department of Electrical Engineering National institute of Technology, Rourkela, 2007 [4] Chandrasekaran, S,. “Integrated magnetics for
interleaved DC-DC boost converter for fuel cell powered vehicles” Rockwell Sci.,Thousand Oaks, CA, USA.
[5] P.Lee, Y.Lee, D.K.W. Cheng and X.Liu,
“Steady-state analysis of an interleaved boost converter with coupled inductors”, IEEE Trans.
Industrial Electronics, pp. 787–79,2000
[6] B. M Hasaneen, “Design and Simulation of DC/DC Boost Converter” by, Faculty of Eng., Al-Azhar University, Kena, Egypt and Adel A.Elbaset Mohammed, Faculty of Engineering, Minia University, Minia, Egypt – December 2008.
[7] Kornetzky, Peter, “A single-Switch AC/DC Converter with Power Factor Correction,” et el Electronics Letters. Vol. 33, no. 25: pp. 2084- 2085,(Dec. 1997)
[8] Balogh.L and Redl.R ,“Power-factor correction with interleaved boost Converters in continuous-inductor-current mode”– Ascom Energy Syst.,Bern, Applied Power Electronics Conference and Exposition,1993.
[9] R. Seyezhai and B.L. Mathur ,“Design and implementation of fuel cell based Interleaved Boost Converter”, At the International Conference on Renewable Energy, University of Rajasthan, Jaipur, ICRE 2011 Jan 17-21, 2011.
[10] Wilson Eberle and Wiliam G. Dunford,
“Efficiency Evaluation of Single-Phase Solutions for AC-DC PFC Boost Converters for Plug-in-Hybrid Electric Vehicle Battery Chargers” Department of Electrical and Computer Engineering University of British Columbia.
