ABSTRACT:
Electric
Vehicle (EV) technology provides an effective solution for achieving better
performance compared to conventional vehicles. This paper highlights the use of
a bidirectional buck-boost converter for a Permanent Magnet Synchronous Motor
(PMSM) driven EV. The bidirectional buck–boost converter interfaces the
low-voltage battery with a high-voltage dc bus and maintains a bidirectional
power flow. The batteries are at low voltage to obtain higher volumetric efficiencies,
and the dc link is at higher voltage to have higher efficiency on the motor
side. PMSMs are known as a good candidate for EV due to their superior
properties such as high torque/volume ratio, power factor and high efficiency.
This paper also includes Space Vector Modulation (SVM) based Direct Torque
Control (DTC) which controls the PMSM to reduce the ripples in both torque and
speed. A closed loop control system with a Proportional Integral (PI)
controller in the speed loop has been designed to operate in constant torque
and flux weakening regions. Extensive simulation work was carried out using
Matlab/ Simulink, and the results established shows that the performance of the
controller both in transient as well as in steady state is quite satisfactory.
KEYWORDS:
1.
Permanent Magnet Synchronous Motor (PMSM)
2.
Electric vehicle
3.
Simulation
4.
SVM
5.
DTC bidirectional converter
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig. 1: Schematic diagram of the
proposed system
EXPERIMENTAL RESULTS:
Fig.
2: Response of reference torque and generated torque
Fig.
3: Response of reference Speed and generated Speed
Fig.
4: Stator Flux
Fig.
5: Stator Flux Trajectory
Fig.
6: Velocity of traction system
Fig.
7: Response of dc link voltage
Fig.
8: Transient state of dc link voltage
Fig.
9: Phase Current of PMSM
CONCLUSION:
The present paper has presented a
bidirectional buck boost converter for a PMSM drive controlled by SVM based
DTC. This controller determinates the desired amplitude of torque hysteresis
band. It is shown that the proposed scheme results in improved stator flux and
torque responses under steady state condition. The main advantage is the
improvement of torque and flux ripple characteristics at any speed region; this
provides an opportunity for motor operation under minimum switching loss and
noise. So this produces the required torque with minimum torque ripples. A
speed controller has been designed successfully for closed loop operation of
the PMSM drive system so that the motor runs at the commanded or reference
speed. The simulated system has a fast response with zero steady state error thus
validating the design method of the speed controller.
REFERENCES:
[1] D. Sandalow, Ending Oil
Dependence. Washington, D.C.: The Brookings Institution, Jan. 2007
[2] A. Emadi, Y. J. Lee, and K.
Rajashekara, “Power electronics and motor drives in electric, hybrid electric,
and plug-in hybrid electric vehicles,” IEEE Trans. Ind. Electron., vol.
55, no. 6, pp. 2237–2245, Jun. 2008.
[3] F. Caricchi, F. Crescimbini, G. Noia,
and D. Pirolo, “Experimental study of a bidirectional DC–DC converter for the
DC link voltage control and the regenerative braking in PM motor drives devoted
to electrical vehicles,” in Proc. IEEE APEC, Orlando, FL, Feb. 1994,
vol. 1, pp. 381–386
[4] Enrique L. Carrillo Arroyo, “Modeling
and simulation of permanent magnet synchronous motor drive system,” M.S Thesis
2006.
[5] J. Rais, M. P. Donsión, “Permanent
Magnet Synchronous Motors (PMSM). Parameters influence on the synchronization
process of a PMSM,” Articel
