Analysis Approach for Five Phase Two-Level Voltage Source Inverter with PWM Technique for Induction Motor Drive

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1 IJSRD - International Journal or Scientiic Research & Deelopent Vol. 1, Issue 3, 013 ISSN (online): Analysis Approach or Fie Phase Two-Leel Voltage Source Inerter with PWM Technique or Induction Motor Drie Ankur P. Desai 1 Vijay G. Bhua 1 Student Assitant Proessor 1, Shantilal Shah Engineering College, Bhanagar, Gujarat, India Abstract this paper gies idea o coparison o ie phase two-leel oltage inerter (FPTLVSI) without ilter circuit and control schee and FPTLVSI with ilter circuit and PWM control schee or induction otor drie. The paper deonstrates using at lab siulations about coparison in ter o haronics analysis or dierent iring angles and ind best angle suitable or output with iniu haronics or FPTLVSI without ilter circuit and control schee and haronics analysis o FPTLVSI with ilter and PWM control schee. This paper suggests siulation o coparison o haronics point o iew ie phase two-leel oltage inerter (FPTLVSI) without ilter circuit and control schee and with ilter circuit and PWM control schee or induction otor drie. Keywords: Modelling o ie phase two-leel oltage inerter (FPTLVSI), PWM control schee or FPTLVSI I. INTRODUCTION RESEARCH interest in the area o ultiphase achines has been steadily increasing oer the past decade [1].The newest deelopents are application-drien (arine electric propulsion, electric ehicles (EVs) and hybrid electric ehicles (HEVs), ore electric aircrat, locootie traction, and high-power applications in general) and the consequence o the adantages oered by ultiphase achines, when copared to the three-phase equialents. These are predoinantly related to the possibility o reduction o the conerter per-phase rating or the gien achine power and to signiicantly iproed ault tolerance, since an n-phase achine can continue to operate with a rotating ield as long as no ore than (n-3) phases are aulted. A urther adantage exists i the ultiphase achine is designed with concentrated stator windings, since it then becoes possible to enhance the torque production by injection o the low-order stator current haronics o an appropriate order. Fie phase induction achine drie. controlled rectiier by arying the conduction angles o the thyristors. The requency o the undaental output is controlled ro the IGBT based oltage source inerter. The subsequent section describes the iplantation issues o control o a ie-phase oltage source inerter. The otiation behind choosing this structure lies in the ault tolerant nature o a ie-phase drie syste. It has been adantage o ie phase induction otor drie like reduction in phase current, reliable in aulty conditions, reduction in current ripple. II. BLOCK DIAGRAM FIVE PHASE TWO LEVEL VOLTAGE SOURCE INVERTER MODEL As shown in ig. each switch in the circuit consists o two power seiconductor deices connected in anti-parallel. One o these is a ully controllable seiconductor, such as a bipolar transistor, MOSFET, or IGBT, while the second is a diode. Fig. : Power Circuit topology o a FPTLVSI The upper and lower power switches o the sae leg are coplientary in operation, i.e. i the upper switch is ON the lower ust be OFF, and ice-ersa. As shown in ig.3, Dead tie is done to aoid shorting the DC supply. Fig.1: Block diagra o ie phase induction otor drie A siple open-loop ie-phase drie structure is elaborated in. The link oltage is adjusted ro the Fig. 3: Illustration or dead tie All rights resered by 488

2 Analysis Approach or Fie Phase Two-Leel Voltage Source Inerter with PWM Technique or Induction Motor Drie III. HARMONICS ANALYSIS OF FPTLVSI. This section presents the coprehensie analysis o siulation results. The perorance o two dierent conduction odes are elaborated in ters o the haronic content in the phase oltages, line oltages and the distortion in the ac side line current. The Fourier series o the phase-to-neutral oltage or 180 conduction ode is obtained as; 1 sint sin 3t V t V sin 7t sin 9t (1) sin11 t Fro aboe equation (1) it ollows that the undaental coponent o the output phase-to-neutral oltage has an RMS alue equal to 0.45 V 1 V V () The Fourier series o the phase-to-neutral oltage or 10 conduction ode is obtained as; cos n 1 sin n 1 t 10 Vt () V n1,,3,.. n 1 (3) Fro aboe equation (3) it ollows that the undaental coponent o the output phase-to-neutral oltage has an RMS alue equal to V cos V 10 V (4) As per the equation o (4) loss in undaental oltage in 10 conduction ode is o the order o 4.89% copared to 180 conduction ode. This loss will aect the loss o torque in the drien achine and subsequently the load will be aected. Howeer, the drop in the torque is not ery signiicant copared to the beneits obtained due to better haronic perorance. Perorance coparison in ters o haronic content in output phase oltage, or dierent conduction odes are presented in ig.10 to 11. It is clearly seen that the haronic content reduces signiicantly with reduction in conduction angle. The haronic content is largest in 180 degree conduction ode and it is least in 10 degree conduction ode. Howeer, the best utilization o aailable link oltage is possible with conentional ten step ode (180 degree conduction ode). It can thus be concluded that a trade-o exist between the loss in undaental and corresponding gain in ters o lower haronic content in output waeor is obtained by using 10 degree conduction ode. A coparison o total haronic distortion in the output phase oltages o ie-phase oltage source inerter or dierent conduction angle is presented. The conduction angles considered are 180, 16, 144, 16, and 108. Thus two ore conduction states are included when copared to urther proe the superiority o control at 10 conduction ode. It is obsered that the lowest THD is obtained or 10 conduction ode. Fig.4 is also at lab siulation o FPTLVSI with balance resistie load. It can be siulated and analysis or dierent iring angles and takes easureent o haronics behaior. Following Table: 1 shows THD Vs dierent iring angles or FPTLVSI without any ilter circuit. Fig.4: Matlab/siulink o FPTLVSI Firing angles THD(Total Haronics Distortion) Table. 1: Dierent iring angles and related THD or haronic analysis o FPTLVSI THD Haronics Analysis o FPTLVSI without Filter Circuit Series1 Firing Angle o FPTLVSI without Filter circuit Fig.5 cure o dierent iring angles and related THD or haronic analysis o FPTLVSI All rights resered by 489

3 Analysis Approach or Fie Phase Two-Leel Voltage Source Inerter with PWM Technique or Induction Motor Drie IV. THE CARRIER-BASED PULSE WIDTH MODULATION (PWM) TECHNIQUE FOR FIVE PHASE INDUCTION MOTOR DRIVE the odulating technique (higher alues o a leads to oer odulation); (b) or odd alues o the noralized carrier requency the haronics in the ac output oltage appear at noralized requencies h centred around and Fig. 6: Single phase hal bridge VSI As entioned earlier, it is desired that the ac output oltage, o an ollow a gien waeor (e.g. sinusoidal) on a continuous basis by properly switching the power ales. The carrier-based PWM technique ulils such a requireent as it deines the on- and o-states o the switches o one leg o a VSI by coparing a odulating signal c (desired ac output oltage) and a triangular waeor (carrier signal). In practice, when c the switch S+ is on and the switch S is o; siilarly, when c < the switch S+ is o and the switch S is on. A special case is when the odulating signal c is a sinusoidal at requency c and aplitude c, and the triangular signal is at requency and aplitude. This is the sinusoidal PWM (SPWM) schee. In this case, the odulation index a (also known as the aplitude-odulation ratio) is deined as a c (1) its ultiples, speciically, h l k l 1,,3,... Where k,4,6,... For l 1,3,5,... And k 1,3,5,... (4) And the noralized carrier requency the requency-odulation ratio) is (also known as c () Figure 7 clearly shows that the ac output oltage is basically a sinusoidal waeor plus 0 an haronics, which eatures: (a) the aplitude o the undaental coponent o the ac output oltage satisying the ollowing expression: i 01 an1 a (3) or a 1, which is called the linear region o 01 Fig. 7: The hal-bridge VSI. Ideal waeors or the SPWM ( a = 0.8, = 9): (a) carrier and odulating signals; (b) switch S+ state;(c) switch S state; (d) ac output oltage; (e) ac output oltage spectru; () ac output current; (g) current; (h) current spectru; (i) switch S+ current; and (j) diode D+ current. or l =, 4, 6, ; the aplitude o the ac output oltage haronics is a unction o the odulation index a and is independent o the noralized carrier requency or > 9; (d) the haronics in the link current (due to the odulation) appear at noralized requencies p centered around the noralized carrier requency and its ultiples, speciically, All rights resered by 490

4 Analysis Approach or Fie Phase Two-Leel Voltage Source Inerter with PWM Technique or Induction Motor Drie p l k 1 l 1,,3,... (5) DC Link Voltage V=00 V beore running siulation gien in coand propt. Freq=50 Hz running siulation gien in coand propt. Where k,4,6,... For l 1,3,5,... And k 1,3,5,... l =, 4, 6, Additional iportant issues are: (a) or sall alues o and the signal ( < 1), the carrier signal c should be synchronized to each other ( integer), which is required to hold the preious eatures; i this is not the case, sub haronics will be present in the ac output oltage. The PWM technique allows an ace output oltage to be generated that tracks a gien odulating signal. A special case is the SPWM technique (the odulating signal is a sinusoidal) that proides, in the linear region, an ac output oltage that aries linearly as a unction o the odulation index, and the haronics are at well-deined requencies and aplitudes. These eatures sipliy the design o iltering coponents. Unortunately, the axiu aplitude o the undaental ac oltage is i / in this operating ode. Higher oltages are obtained by using the oer odulation region ( a > 1); howeer, loworder haronics appear in the ac output oltage. Very large alues o the odulation index ( a > 3.4) lead to a totally square ac output oltage that is considered as the square-wae odulating technique Fig. 9: Matlab/siulation results or output phase oltages o Three phase two-leel oltage source inerter and ie phase two-leel oltage source Matlab siulink odel o ie phase two-leel oltage source inerter with PWM technique Fig. 10: Matlab/siulation results or output load currents o three phase two-leel oltage source inerter and ie phase two-leel oltage source Fig. 8: Matlab/siulink odel or PWM Method o ie phase induction otor drie V. RESULTS Matlab/siulation results o three phase two-leel oltage source inerter and ie phase two-leel oltage source Siulation results o or TPTLVSI and FPTLVSI the operating conditions gien below are shown in Fig.7 to ig.11. Siulation results show output phase oltages, line oltage currents, gate triggering, load current, haronics analysis or ie phase two leel oltage inerter. Operating condition: Siulation tie: 0.0 sec Fig.11: Matlab/siulation results or Input signal, carrier signal and PWM ethod All rights resered by 491

5 Analysis Approach or Fie Phase Two-Leel Voltage Source Inerter with PWM Technique or Induction Motor Drie Haronic analysis o output line oltages o one o the phase o FPTLVSI without any control schee and ilter is carried out with dierent iring angle o gating circuit o FPTLVSI and result is obtained that at 10 0 optial alue o THD o line oltage o Haronic analysis o output line oltages o one o the phase o FPTLVSI with PWM control schee and ilter is carried out and result is obtained that THD o o output line oltages o one o the phase o FPTLVSI is reduced greatly with alue o This paper has reiewed analytical approach or ie phases two leel oltage inerter used in application o induction otor drie. REFERENCES Fig. 1: Matlab/siulation results or output oltages (without ilter) o ie phase two-leel VSI Fig. 13: Matlab/siulation results or output oltages (with ilter and PWM control schee) o ie phase two-leel VSI Fig.14: Matlab/siulation results or FFT analysis output oltages (with ilter and PWM control schee) o ie phase two-leel VSI [1] E. Lei, R. Bojoi, F. Prouo, H. A. Toliyat, and S. Williason, Multiphase induction otor dries A technology status reiew, IET Electr. Power Appl., ol. 1, no. 4, pp , 007. [] Grandi, G. Serra, and A. Tani, General analysis o ulti-phase systes based on space ector approach, in Proc. Int. Power Electr. Motion Control Con. (EPE- PEMC), Portoroz, Sloenia, 006, pp [3] Y. Zhao and T. A. Lipo, Space ector PWM control o dual three-phase induction achine using ector space decoposition, IEEE Trans. Ind.Appl., ol. 31, no. 5, pp , Sep./Oct [4] P. S. N. de Sila, J. E. Fletcher, and B. W. Willias, Deelopent o space ector odulation strategies or ie-phase oltage source inerters, in Proc. Inst. Electr. Eng. Power Electr. Mach. Dries Con. (PEMD), Edinburgh, U.K., 004, pp [5] D. Dujic, E. Lei,M. Jones, G. Grandi, G. Serra, and A. Tani, Continuous PWM techniques or sinusoidal oltage generation with seen-phase oltage source inerters, in Proc. IEEE Power Electr. Spec. Con. (PESC), Orlando, FL, 007, pp [6] G. Grandi, G. Serra, and A. Tani, Space ector odulation o a seen phase oltage source inerter, in Proc. Int. Syp. Power Electron. Electr. Dries, Auto. Motion (SPEEDAM), Taorina, Italy, 006, pp [7] D. Dujic, M. Jones, and E. Lei, Space-ector PWM or nine-phase VSI with sinusoidal output oltage generation, in Proc. IEEE Ind. Electron.Soc. Annu. Meeting (IECON), Taipei, Taiwan, 007, pp VI. CONCLUSION A coparison o total haronic distortion in the output phase oltages o ie-phase oltage source inerter or dierent conduction angle is presented. The conduction angles considered are 180, 16, 144, 16, and 108. Thus two ore conduction states are included when copared to urther proe the superiority o control at 10 conduction ode. It is obsered that the lowest THD is obtained or 10 conduction ode. All rights resered by 49