ABSTRACT:
This work presents a power factor correction (PFC) based
bridgeless isolated Cuk converter fed brushless DC (BLDC) motor drive. A
variable DC link voltage of the voltage source inverter (VSI) feeding BLDC
motor is used for its speed control. This allows the operation of VSI in
fundamental frequency switching (FFS) to achieve an electronic commutation of
BLDC motor for reduced switching losses. A bridgeless configuration of an
isolated Cuk converter is derived for elimination of front end diode bridge
rectifier (DBR) to reduce conduction losses in it. The proposed PFC based
bridgeless isolated-Cuk converter is designed to operate in discontinuous inductor
current mode (DICM) to achieve an inherent PFC at AC mains. The proposed drive
is controlled using a single voltage sensor to develop a cost effective
solution. The proposed drive is implemented to achieve a unity power factor at
AC mains for a wide range of speed control and supply voltages. An improved power
quality is achieved at AC mains with power quality indices within limits of IEC
61000-3-2 standard.
KEYWORDS:
1.
BLDC Motor
2.
Bridgeless
Isolated Cuk Converter
3.
Discontinuous
Inductor Current Mode
4.
Power Factor
Correction
5.
Power Quality
6.
Voltage Source
Inverter
SOFTWARE: MATLAB/SIMULINK
CIRCUIT DIAGRAM:
Fig.
1. Proposed configuration of a bridgeless isolated Cuk converter feeding BLDC
motor drive.
Fig.
2. Test results of the proposed drive during its operation at rated loading condition
with DC link voltage as (a) 130 V and (b) 50 V.
Fig.
3. Test results of the proposed drive during its operation at rated condition
showing (a) input inductor currents (b) output inductors current and (c) HFT
currents.
Fig.
4. Test results of the proposed drive during its operation at rated condition
showing intermediate capacitors voltages (a) VC11 and VC12 and (b) VC21 and
VC22.
Fig.
5. (a) Test results of the proposed drive during its operation at rated condition
showing (a) voltage and current stress on PFC converter switches and (b) its
enlarged waveforms.
Fig.
6. Test results of the proposed drive during (a) starting at DC link voltage of
50V, (b) speed control corresponding to change in DC link voltage fro 50V to
100V and (c) supply voltage fluctuation from 250V to 200V.
CONCLUSION:
A
new configuration of bridgeless isolated-Cuk converter fed BLDC motor drive has
been proposed for low power household appliances. The speed control of BLDC
motor has been achieved by controlling the DC link voltage of VSI feeding BLDC
motor. This has facilitated the operation of VSI in low frequency switching
mode for reducing the switching losses associated with it. This bridgeless
isolated-Cuk converter has been designed for the elimination of diode bridge
rectifier at the front-end for reducing the conduction losses in the front-end
converter. This PFC converter has been operated in DICM for DC link voltage
control and inherent power factor correction is achieved at the AC mains. A prototype
of proposed drive has been implemented using a DSP. Satisfactory test results
for proposed bridgeless isolated- Cuk-converter fed BLDC motor has been
evaluated for its operation over complete speed range. Moreover, the performance
of proposed drive is also evaluated for operation at wide range of supply
voltages. The obtained power quality indices have been found within the limits
of power quality standards such as IEC 61000-3-2.
REFERENCES:
[1]
C. L. Xia, Permanent Magnet Brushless DC Motor Drives and Controls Wiley
Press, Beijing, 2012.
[2]
Y. Chen, C. Chiu, Y. Jhang, Z. Tang and R. Liang, “A Driver for the Single-Phase
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[3]
X. Huang, A. Goodman, C. Gerada, Y. Fang and Q. L Matrix Converter Drive for a
Brushless DC Motor in Aerospace Applications,” IEEE Trans. Ind. Elect., Sept.
2012.
[4]
J. Moreno, M. E. Ortuzar and J. W. Dixon, “Energy for a hybrid electric
vehicle, using ultra capacitors and neural networks,” IEEE Trans. Ind.
Electron., vol.53, no.2, pp. 614
[5]
P. Pillay and R. Krishnan, “Modeling of permanent magnet motor drives,” IEEE
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