ABSTRACT:
In this paper, methods for sizing of PV pumping systems
and the simulation of (DTC) Direct Torque Control of induction motor that is
used for piloting a water pump supplied by a photovoltaic generator are
presented. The sizing of the PV pumping system is based on the calculation of
the water needs, the required hydraulic energy and the estimation of available
solar power. The best sizing of the PV pumping system may further help in
reducing its cost and optimize its efficiency. The proposed system includes a
solar panel, a DC/DC converter with MPPT control, a voltage inverter with pulse
width modulation (PWM). The Pump is driven by a Three Phase Induction Motor. In
order to control the water flow in the pump, Direct torque control of induction
machine is used. The simulations are carried out in Matlab/Simulink.
KEYWORDS:
1.
MPPT
2.
DTC
3.
PV pumping
4.
Photovoltaic
5.
Three phase
induction motor
6.
Induction
machine (IM)
7.
Voltage
inverter
8.
Pulse width
modulation (PWM)
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig. 1. System block diagram
Fig.
2. Band hysteresis of flux
Fig. 3. Statoric Flux evolution
Fig.
4. Electromagnetic Torque
Fig.
5. Stator current dq Axis
Fig.
6. The motor speed
CONCLUSION:
In
this paper, a case study of stand-alone PV pumping system designed for
irrigation needs in a remote site in Tunisia. The sizing method for the
structure was presented. MPPT technique was used to optimize the power
delivered by the photovoltaic module. Direct torque control technique served to
control the induction machine speed and therefore the flow of the centrifugal
pump. The paper presented the system block diagram, the MPPT control algorithm,
the DTC block diagram and design. The main objective of this work is to
maximize savings in energy consumption by ensuring that pipelines and networks
are sized and designed accurately. The use of DTC technique ensures better
efficiency of the motor. The experimental results are satisfactory and suggest
that the proposed solution can be a reliable option to overcome the lack of
electricity at remote locations and rural areas. More reliability test and
studies needs to be performed to guarantee its robustness, efficiency and cost
effectiveness.
REFERENCES:
[1]
“Solar resource maps for Tunisia”, Solargis S.R.O Slovakia, Maps.
[2]
Chaabane. M, Ben Djemaa. A. and Kossentini, “A daily and hourly global
irradiations in Tunisia extracted from Meteosat Wedax images”, Solar Energy,
vol. 57, issue 6, pp. 449-457.
[3]
Information obtained from the direction of the bureau of organic farming, CRDA
Tozeur.
[4]
T. Augustyn. “Energy efficiency and savings in pumping systems, The holistic
approach”, Energy Efficiency Convention (SAEEC), 2012 Southern African.
[5]
Jim McGovern, “Technical Note: Friction Factor Diagrams for Pipe Flow”, Dublin
Institute of Technology, 2011.
