Voltage Balancing Scheme in MMC – A New Approach
-
Sreedhar Madichetty
,
Abhijit Dasgupta
Abstract
This article proposes an online voltage balancing scheme using a new comparative reference wave modulation technique applied to modified modular multilevel converter (MMMC). Recent applications of modular multilevel converter (MMC) in high-voltage DC systems experience many problems with unbalancing of upper and lower arms, due to which circulating currents are rotating in the legs of MMC. These circulating currents pass through the arm inductors and create power loss across the inductor which consequently affects the efficiency of system. In order to overcome the unbalancing and to reduce the power losses, it proposes a new topology for existing MMC called as MMMC. Its main idea is to the balance the system voltage according to the difference between upper and lower arm currents. The upper and lower arm capacitors voltages can be well balanced by proposed technique. Compared to conventional PWM methods, this method can be realized easily. Particularly, this method has not used any kind of sorting technique, which makes it suitable for MMC with a large number of sub-modules. With experiments, the proposed method has been verified successfully.
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©2014 by De Gruyter
Articles in the same Issue
- Frontmatter
- Research Articles
- A Comparative Study of Mathematical Modeling of Photovoltaic Array
- A New Advanced Topology of Stacked Multicell Inverter
- Augmented State Approach in Quasi-Sliding-Mode Controlled PEBB-Based Power Converters
- Evaluation of Gas Insulated Disconnector Switch for Bus Charging and Bus Transfer Currents
- Grid Stabilization with Decentralized Controllable Loads using Fuzzy Control and Droop Characteristics
- Novel Scheme to Improve Power Factor of Slip Energy Recovery Drive by Selective Harmonic Elimination
- Single-Phase Power Generation Using Three-Phase Self-Excited Synchronous Reluctance Generator
- Voltage Balancing Scheme in MMC – A New Approach
- Modelling and Analysis of a Three-Phase to Five-Phase Transformer
- Novel Cell Flying Capacitor Converter Topology with Significant Reduction in Number of Components
Articles in the same Issue
- Frontmatter
- Research Articles
- A Comparative Study of Mathematical Modeling of Photovoltaic Array
- A New Advanced Topology of Stacked Multicell Inverter
- Augmented State Approach in Quasi-Sliding-Mode Controlled PEBB-Based Power Converters
- Evaluation of Gas Insulated Disconnector Switch for Bus Charging and Bus Transfer Currents
- Grid Stabilization with Decentralized Controllable Loads using Fuzzy Control and Droop Characteristics
- Novel Scheme to Improve Power Factor of Slip Energy Recovery Drive by Selective Harmonic Elimination
- Single-Phase Power Generation Using Three-Phase Self-Excited Synchronous Reluctance Generator
- Voltage Balancing Scheme in MMC – A New Approach
- Modelling and Analysis of a Three-Phase to Five-Phase Transformer
- Novel Cell Flying Capacitor Converter Topology with Significant Reduction in Number of Components
