Multilevel Power Converter Module Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current high voltage direct current (HVDC) transmission systems require a large number of modules in modular stacked power converters, leading to complexity and high costs due to the use of two-level and three-level voltage source converters, which complicates AC-DC power conversion.
Innovation Solution
A power converter module with a voltage source current controlled configuration providing unidirectional current and (2n+1) output voltage levels, featuring parallel conductive paths with diodes and switches, and energy storage elements to reduce module count and complexity, including diode clamped, actively clamped, and floating capacitor configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If two-level and three-level voltage source modular power converters are used, then AC-DC power conversion capability is achieved, but the number of modules increases leading to complexity and high costs
Solution Approach 1:
The power converter is divided into multiple modular units, each containing switches, diodes, and energy storage elements. These modules are stacked in series to achieve the desired voltage levels and power conversion capability while maintaining modularity for ease of manufacture and assembly.
Solution Approach 2:
Multiple conductive paths with switches and diodes are merged into a single modular structure that provides both rectification and inversion functions. The energy storage elements are shared across parallel paths, reducing the total component count while maintaining the required AC-DC power conversion capability.
2Power
If a high number of modules are coupled together to form modular stacked power converter, then desired AC-DC power conversion capability is achieved, but system complexity and costs increase
Solution Approach 1:
Each modular unit is designed to perform multiple functions including voltage conversion, current control, and energy storage. The universal module design allows the same structure to be used across different voltage levels and power ratings, reducing overall system complexity while achieving the desired power conversion capability.
Solution Approach 2:
The patent transitions from traditional two-level and three-level converters to a multilevel modular architecture where voltage levels are achieved by stacking modules in series. This dimensional change from planar to vertical stacking reduces the number of components required within each level while maintaining the required voltage and power conversion capabilities.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A power converter module including a voltage source current controlled power converter for providing unidirectional current having at least four output voltage levels is provided. The voltage source current controlled power converter includes an input terminal and an output terminal, and a first conductive path and a second conductive path is coupled in parallel to each other between the input terminal and the output terminal. Each of the conductive paths comprises at least one diode and at least one switch coupled in series to the respective conductive path. The at least one diode in the first conductive path are coupled closer to the input terminal and the at least one diode in the second conductive path are coupled closer to the output terminal. The voltage source current controlled power converter further includes at least two energy storage elements coupled between the first conductive path and the second conductive path.