This paper presents a solar power based three-level neutral clamped inverter (3LNCI) fed induction motor drive (IMD) with space vector modulation based direct torque and flux control (DTFC-SVM) for the water pumping applications. Due to the robustness and the flexible operating characteristics, induction motor is most suitable for water pump system. A DC/DC boost converter along with perturb and observe method of maximum power point tracking (MPPT) control technique is employed to draw sophisticated power from the solar photovoltaic (PV) array. The DTFC-SVM of an IMD using 3LNCI is proposed for improving performance and reducing the ripple contents of torque, flux and stator currents. The proposed method is simulated in MATLAB/SIMULINK environment and simulated results are presented under various operating conditions.
- Direct torque and flux control
- Induction motor drive
- Space vector modulation
- Three-level diode clamped inverter
- Photovoltaic array
Fig. 1. Schematic model of DTFC-SVM of IMD
EXPECTED SIMULATION RESULTS:
Fig. 2. Results under no-load torque operating condition using (a) 2LI and (b) 3LNCI: Plot (from top to bottom): (i) Torque, (ii) stator current, (iii) speed, (iv) stator flux qd-components in stationary reference frame.
Fig. 3. Loading performance at 1400rpm using (a) 2LI and (b) 3LNCI: (i) Torque, (ii) speed, (iii) stator current and (iv) error speed.
Fig. 4. Reversal speed Performance using (a) 2LI and (b) 3LNCI: (i) Torque, (ii) speed, (iii) stator current and (iv) stator flux qd-components.
It has been concluded that the solar powered three-level neutral clamped inverter fed induction motor drive with DTFCSVM using proportional-integral controller (PIC) quite suitable for the water pumping applications. The solar panel has been operated at the peak values of voltage, current and power by using a simple perturb and observe method of MPPT algorithm, and the required DC output voltage achieved by using DC/DC boost converter. From the simulation results we can conclude that the three-level SVM based IM drives can provide better performance and torque ripple levels are also lowerd in comparision with Two- level SVM based IM drive.
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