TG E. Multilevel Inverters. Topologies,. Modulation Techniques and. Practical
Problems. Electronic Engineering Department. University of Seville. Camino de
los ...
• Inverter Topologies Ø Diode Clamped Ø Flying Capacitor Ø Cascade Inverters • Modulation techniques Ø PWM Ø Space Vector • Applications Ø Motor drives Ø Active filters Ø… • Practical problems Ø Voltage balancing Ø Control complexity Ø…
Multilevel Inverters. Topologies, Modulation Techniques and Practical Problems Multilevel Inverter Topologies:
Diode Clamped Converter
VDC1
VDC2 Cascade Converter
Prof. Leopoldo G. Franquelo
[email protected]
Flying Capacitor Converter Electronic Engineering Department. University of Seville Camino de los Descubrimientos s/n 41092 Seville, SPAIN
G GT TEE
Multilevel Inverters. Topologies, Modulation Techniques and Practical Problems Modulation Techniques: Complex problem!
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Simple algorithms Very low computational cost High efficiency
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• Inverter Topologies Ø Diode Clamped Ø Flying Capacitor Ø Cascade Inverters • Modulation techniques Ø PWM Ø Space Vector • Applications Ø Motor drives Ø Active filters Ø… • Practical problems Ø Voltage balancing Ø Control complexity Ø…
3-phase unbalanced system
3-phase unbalanced system
with the third armonic
with zero sequence
Van
2D Modulation results
Even for unbalanced topologies using 3D modulation algorithms!
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Extremely simple and generalized modulation algorithms based on geometrical considerations
3D Modulation results
G GT TEE
• Inverter Topologies Ø Diode Clamped Ø Flying Capacitor Ø Cascade Inverters • Modulation techniques Ø PWM Ø Space Vector • Applications Ø Motor drives Ø Active filters Ø… • Practical problems Ø Voltage balancing Ø Control complexity Ø…
Multilevel Inverters. Topologies, Modulation Techniques and Practical Problems β
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2D and 3D modulation algorithms for multilevel converters are based on the reduction of the N-level problem to an 2-level problem using normalizations and geometrical considerations b
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100 a
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• Inverter Topologies Ø Diode Clamped Ø Flying Capacitor Ø Cascade Inverters • Modulation techniques Ø PWM Ø Space Vector • Applications Ø Motor drives Ø Active filters Ø… • Practical problems Ø Voltage balancing Ø Control complexity Ø…
Multilevel Inverters. Topologies, Modulation Techniques and Practical Problems Applications:
Filter current: Reference Actual
Power Grid AC/DC DC/AC Converter Converter
Motor control
Active Filters: • Topologies • Control algorithms
Practical problems: One of the most important problems in multilevel converters is the voltage balancing
Generalized algorithms for several multilevel topologies and for any number of levels Very low computational cost High efficiency
MATHEMATICAL MODELS
SIMULATION MODELS MatLab/Simulink® & PSCAD ®
EXPERIMENTAL RESULTS
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