A Novel Level Shifted Modulation Technique for Seven Level Multilevel Inverter
DOI:
https://doi.org/10.46243/jstj.2017.v2.i4.160Keywords:
Active Power Filter, Harmonic, Instantaneous P Q Theory, Balanced, Unbalanced Loads, DC Link Voltage Controller, Voltage Source Inverter(VSC)Abstract
— In phased-shifted modulation, a multilevel inverter with m voltage levels requires (m – 1) triangular carriers. In the phase-shifted multicarrier modulation, all the triangular carriers have the same frequency and the same peak-to-peak amplitude, but there is a phase shift between any two adjacent carrier waves, given by Ɵcr = 360°/(m – 1). In the case of a 7-level CHB (m = 7), as we used in our project, all carrier waves (7-1 = 6) are 60o apart from the neighboring carrier waves. Similar to the phase- shifted modulation, an m-level CHB inverter using level shifted multicarrier modulation scheme requires (m – 1) triangular carriers, all having the same frequency and amplitude. The (m – 1) triangular carriers are vertically displaced such that the bands they occupy are contiguous. The frequency modulation index is given by mf = fcr/fm. In the case of a 7-level CHB (m = 7), as we used in our project, all carrier waves (7-1 = 6) are displaced from the neighbouring carrier waves.
References
Jose Rodriguez, Steffen Bernet, Peter K. Steimer, Ignacio E. Lizama, ―A Survey on Neutral-Point-Clamped Inverters, ―IEEE transactions on industrial electronics, VOL. 57, NO. 7, JULY 2010
J. Rodriguez, J.-S. Lai, and F. Z. Peng, ―Multilevel inverters: a survey of topologies, controls, and applications, ― IEEE Trans. Ind. Electron., vol. 49, pp. 724-738, 2002
J. S. Lai and F. Z. Peng, ―Multilevel converters–A new breed of power converters, ―IEEE Trans. Ind. Applicant., vol. 32, pp. 1098–1107, May/June 1996. Phase shifted PWM Method Vab and Van
Z. Pan, F. Zheng Peng and all, ―Voltage Balancing Control of Diode-Clamped Multilevel Rectifier/Inverter Systems‖, IEEE transactions On Industry Applications, Vol-41. N° 6, Nov/Dec 2005, pp. 1668-1706
Rangarajan M. Tallam, Rajendra Naik, and Thomas A.Nondahl,Fellow, ―A Carrier-Based PWM Scheme for Neutral-Point Voltage Balancing in Three-Level Inverters, ’’ IEEE Trans. Ind. Appl., vol. 41, no. 6,PP. 1734-1743, November/December 2005
K. Narasimha Raju and Venu Gopala Rao Mannam, ―An effective carrier based PWM technique for neutral point voltage stabilization of three level inverter,‖ in IEEE conf. on Smart Electric Grid (ISEG), 2014
Nikola Celanovic, and Dushan Boroyevich, ―A Comprehensive Study of Neutral-Poin Voltage Balancing Problem in Three-Level Neutral-Point-Clamped Voltage Source PWM Inverters, ‖IEEE Trans.Ind.Appl., vol. 15, no. 2,PP. 242-249, March 2000
Amit Kumar Gupta, and Ashwin M. Khambadkone, ―A Simple Space Vector PWM Scheme to Operate a Three-Level NPC Inverter at High THD Analysis for Phase shifted PWM Method Vab Modulation Index Including Over modulation Region, With Neutral Point Balancing, ―IEEE Trans.Ind.Appl., vol. 43, no. 3, PP. 751- 760May/June 2007
Jordi Zaragoza, Josep Pou, Salvador Ceballos, Eider Robles, Pedro Ibáñez and Jose Luis Villate, ―A Comprehensive Study of a Hybrid Modulation Technique for the Neutral-Point-Clamped Converter, ―IEEE Trans. Ind. Appl., vol. 56, no. 2,PP. 294-304, February 2009
Georgios I. Orfanoudakis, Michael A. Yuratich, and Suleiman, ―Hybrid Modulation Strategies for Eliminating Low-Frequency Neutral-PointVoltage Oscillations in the Neutral-Point-Clamped Converter, ―IEEE Trans. Pow.Elec.,vol 28,no.8,PP. 3653- 3658,August 2013 36
K Narasimha Raju, M Rao, M Ramamoorthy, ―Hybrid modulation technique for neutral point clamped inverter to eliminate neutral point shift with minimum switching loss,‖ in TENCON conf
Rasoul Shalchi Alishah, Seyyed Hossein Hosseini ―A New Multilevel Inverter Structure For High-PowerApplications using Multi-carrier PWM Switching Strategy‖ International Journal of Power Electronics and Drive System (IJPEDS) Vol. 6, No. 2, June 2015, pp. 318~325 ISSN: 2088-8694
P. N. Tekwani, P. N. Tekwani, and K. Gopakumar, ―A Dual Five-Level Inverter-Fed Induction Motor Drive With Common-Mode Voltage Elimination and DC-Link Capacitor Voltage Balancing Using Only the Switching-State Redundancy—Part I, ―IEEE Trans.Ind.Appl., vol. 54, no. 5,PP. 2600-2608, October 2007
P. N. Tekwani, P. N. Tekwani, and K. Gopakumar, ―A Dual Five-Level Inverter-Fed Induction Motor Drive With Common-Mode Voltage Elimination and DC-Link Capacitor Voltage Balancing Using Only the Switching-State Redundancy—Part II, ―IEEE Trans.Ind.Appl., vol. 54, no. 5,PP. 2609-2617, October 200
Chenchen Wang, and Yongdong Li, ―Analysis and Calculation of Zero-Sequence Voltage Considering Neutral-Point Potential Balancing in Three-Level NPC Converters, ―IEEE Trans.Ind.Appl., vol. 57, no. 7,PP. 2262-2271, July 2010
Joachim Holtz, and Nikolaos Oikonomou, ―Neutral Point Potential Balancing Algorithm at LowModulation Index for Three-Level Inverter Medium-Voltage Drives, ―IEEE Trans.Ind.Appl., vol. 43, no. 3, PP.761-768,May/June 2007
Till Boller, Joachim Holtz, and Akshay K. Rathore, ―Neutral-Point Potential Balancing UsingSynchronous Optimal Pulsewidth Modulation of Multilevel Inverters in Medium-Voltage High-Power AC Drives, ―IEEE Trans.Ind.Appl., vol. 50, no. 1,PP.549-557, January/February 2014
Bin Wu,IEEE Press,Wiley Interscience, ―High-power converters and AC drives, ― 2006
