**6. Experimental evaluation**

Figure 15 shows the experimental filtered inverter output voltage (VC1-VC2) for frequency value equal 50 Hz. The filtered inverter output voltage is perfectly sinusoidal. The experimental result in Figure 16 shows the torque response obtained by using the proposed PCPWM inverter: during the period between 0.65 sec and 1.95 sec, a load torque equal to 13 (N.m) is applied. The torque ripple of the induction motor is dramatically reduced.

**Figure 14.** Snapshot of the laboratory experimental setup

482 Induction Motors – Modelling and Control

Matlab Simulink Version R2000a

Card dSPACE DS 1103

*TM320F240* 

*Control algorithm* 

**DS 1103** 

**Figure 13.** Global scheme of the experimental setup

**6. Experimental evaluation** 

control algorithm to be run on the hardware.

designed in Simulink/Matlab, then, the Real-Time Workshop is used to automatically generate optimized C code for real time application. Afterward, the interface between Simulink/Matlab and the Digital Signal Processor (DSP) (DS1103 of dSPACE) allows the

The master bit I/O is used to generate the required 2 gate signals, and a several Analog-to-Digital converters (ADCs) are used for the sensed line-currents, capacitors voltage, and output voltage. An optical interface board is also designed in order to isolate the entire DSP master bit I/O and ADCs. The block diagram of the experimental plant is given in figure 14

R

*Resolver* 

*Induction motor* 

Figure 15 shows the experimental filtered inverter output voltage (VC1-VC2) for frequency value equal 50 Hz. The filtered inverter output voltage is perfectly sinusoidal. The experimental result in Figure 16 shows the torque response obtained by using the proposed PCPWM inverter: during the period between 0.65 sec and 1.95 sec, a load torque equal to 13

(N.m) is applied. The torque ripple of the induction motor is dramatically reduced.

*Specific circuit* 

*Incremental encoder* 

> *Isolation amplifier*

*Three- phase inverter* 

*Isolation and protection card Control signals generator* 

**Figure 15.** Experimental inverter filtered output voltage.

**Figure 16.** Experimental torque response for proposed PCPWM inverters

Moreover, as shown in Figure 17, the experimental switching frequency of the proposed PCPWM inverter is very less compared to the conventional PWM inverter one Figure 18. As a consequence, the proposed inverter provides higher dynamic response than the conventional PWM inverter in vector controlled induction motor applications.

Minimizing Torque-Ripple in Inverter-Fed Induction Motor Using Harmonic Elimination PWM Technique 485

*Université Docteur Yahia Farès de Médéa, Département Génie Electrique, Algérie* 

Symbol Quantity Value

Bäck, T. (1996). *Evolutionary Algorithms in Theory and Practice*, Oxford University Press, 1996 Bouchhida, O.; Cherifi, A. & Boucherit, M.S. (2007). Novel harmonic elimination PWM Technique for reducing Torque–Ripple in Inverter-fed Induction motor. *Archives of* 

Bouchhida, O.; Benmansour, K.; Cherifi, A. & Boucherit, M.S. (2008). Low switchingfrequency and novel harmonic elimination for three-phase inverter', *Proceedings of the Fifth International Multi-Conference on Systems, Signals and Devices SSD08, IEEE*,

Bouchhida, O. (2008). *Contribution à l'Optimisation de Structure des Convertisseurs pour la Commande des Machines Asynchrones: Réalisation expérimentale*. thèse de Doctorat, Ecole

*Electrical Engineering (AEE)*, Vol. 56, No.3-4, (Mar. 2007), 197-212.

Philadelphia University Amman Jordan, July 2008.

Nationale polytechnique ENP d'Alger, Algérie

1.5 KW 220/380 V 10 Nm 2 5.62 Ω 4.37 Ω 0.46 H 0.48 H 0.48 H 6.4/3.7 A 1480 tr/min 0.001136 N.m.s/rd 0.0049 kg.m² 10 mF 0.5 mH 0.5Ω

Rated power Rated line voltage Rated load torque No. of pole pair Stator resistance Rotor resistance Mutual inductance Stator leakage inductance Rotor leakae inductance Rated current Motor speed Viscosity coefficient Moment of inertia Capacitance Inductance Internal inductor resistance

*Ecole Nationale Polytechnique, Département Génie Electrique, Algérie* 

**Author details** 

Ouahid Bouchhida

Abederrezzek Cherifi

**Appendix** 

Pn Vn Cn P Rs Rr Msr Ls Lr In Ω<sup>n</sup> f J C1, C2, C3 L R

**8. References** 

Mohamed Seghir Boucherit

*IUT Mantes-en-Yvelines, France* 

The squirrel cage induction motor data are:

**Figure 17.** Experimental switching frequency for proposed PCPWM inverters

**Figure 18.** Experimental switching frequency for conventional PWM inverters
