Stability analysis of multicell converters

The multicell converter topology possesses a natural voltage balancing property. This paper uses models obtained previously to perform a stability analysis of multicell converters for the general case of p-cells. It uses a generic model in steady-state- and time constant analyses to determine the stability of multicell converters. In this paper stability refers to balanced cell capacitor voltages, whereas instability refers to unbalanced cell capacitor voltages. The stability analysis is performed for both sinusoidal modulation as well as fixed duty-cycle modulation. The model used in the stability analyses in this paper is valid for any modulation method. The conditions that lead to stability of the cell capacitor voltages as well as that leading to instability are presented. Theoretical results are included to verify the presented stability analyses and properties.Conference Pape

Natural balance of multicell converters

The multicell converter topology is said to possess a natural voltage balancing property. This paper models multicell converters for the general case of p-cells. It describes the relationship between the models for different numbers of cells in a generic model for a p-cell multicell converter. The switching functions used in switching these converters are mathematically analyzed. Equivalent circuits are derived and presented. The switching and balancing properties of these converters are mathematically analyzed. Multicell converters were modeled previously for both sinusoidal and fixed duty-cycle references. The model discussed in this paper is valid for any modulation method. The conditions for balanced cell capacitor voltages are presented from the aforementioned mathematical synthesis. The balancing property of these converters is also proved mathematically from the presented properties and conditions for natural balancing are discussed. The balancing properties and conditions are formulated and presented as a "Natural Balance Theory for Multicell Converters". Simulation and experimental results are included to verify the presented balance theory and properties. Conclusions presented include conditions for the theory to be valid as well as possible extensions to the theory and practical implications on converter design.Conference Pape

Stability analysis of multicell converters using Gerschgorin circles

The multicell converter topology possesses a natural voltage balancing property. This paper uses models obtained previously to perform a stability analysis of multicell converters. It uses a generic model in steady-state- and time constant analyses to determine the stability of multicell converters. In this paper stability refers to balanced cell capacitor voltages, whereas instability refers to unbalanced cell capacitor voltages. The stability analysis is performed for both sinusoidal modulation as well as fixed duty-cycle modulation. The model used in the stability analyses in this paper is valid for any modulation method. The conditions that lead to stability of the cell capacitor voltages as well as that leading to instability are presented. Theoretical results are included to verify the presented stability analyses and properties. Copyright © 2004 IEEE.Articl

Voltage unbalance in the multicell converter topology

The muticell converter topology is said to possess a natural voltage balancing property. This paper models a 2-cell multicell converter. The switching and balancing properties of this converter is mathematically analyzed and presented. The balancing property of this converter is also proven mathematically from the presented properties and conditions for natural balancing are discussed.Conference Pape