Module-Shared Flexible Loop Controller Topology for Lower Power Loss

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing flexible closed-loop controllers for power distribution networks face inefficiencies and high costs due to complex control systems, large volumes, and reduced safety, especially with the use of many high-frequency transformers, which complicates power flow management and reliability.

Innovation Solution

A power network flexible controller topology shared by modules, utilizing a cascaded H-bridge structure with non-shared and shared modules, including full-bridge rectifiers and high-frequency isolation units, reduces power loss and equipment volume by optimizing the number of full bridges and transformers, and allows for efficient power flow control between distribution network nodes with small voltage and phase angle differences.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If MMC-based flexible controller is used, then modularity and easy expansion are improved, but device complexity and cost increase

Engineering Contradiction:

ImprovemodularityVSAvoidcontrol complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The flexible controller is divided into multiple identical modular units, each comprising a full-bridge converter and associated components. These modules are connected in series to form the complete controller, enabling independent control of each module and simplifying the overall control architecture while maintaining modularity and expandability

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Each modular unit in the series-connected architecture performs multiple functions including voltage regulation, power flow control, and harmonic filtering. The standardized module design allows the same circuit topology to handle both AC-AC conversion and AC-DC conversion tasks, reducing control complexity

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If MMC-based flexible controller is used, then modularity is improved, but device volume and cost increase

Engineering Contradiction:

ImprovemodularityVSAvoiddevice volume

Core Design Contradiction:

Adaptability or versatilityVSVolume of stationary object

Solution Approach 1:

Multiple full-bridge converter modules are connected in series within a unified controller structure, sharing common DC capacitors and control circuits. This merging approach reduces redundant components and minimizes overall device volume while preserving modular architecture benefits

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The series-connected modular design allows each module to serve multiple functional purposes, reducing the total number of components needed. The shared DC side infrastructure and common control architecture eliminate duplicate elements, thereby reducing device volume

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If CHB-based flexible controller with many high-frequency transformers is used, then modularity is improved, but device volume increases and power transmission efficiency decreases

Engineering Contradiction:

ImprovemodularityVSAvoidpower transmission loss

Core Design Contradiction:

Adaptability or versatilityVSLoss of energy

Solution Approach 1:

The invention extracts and eliminates the high-frequency transformer component from each CHB module, replacing it with a direct series-connected full-bridge converter architecture. This removal of unnecessary isolation transformers reduces power loss while maintaining the modular structure through series connection of converter modules

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the magnetic isolation mechanism (high-frequency transformers) with an electrical isolation approach using series-connected voltage sources. The full-bridge converters provide galvanic isolation through their switching operation and capacitor coupling, eliminating the need for physical transformer components and reducing associated power losses

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS11929624B2Module-shared flexible loop closing controller topology for power grid

Publication Date: 2024.03.12 SOUTHEAST UNIV

AI summary

The invention discloses a power network flexible controller topology shared by modules. Each single-phase topology comprises an AC/AC converter including N1 CHB modules, and an AC/DC module including N−N1 full-bridge rectifiers; the AC input terminals of N1 CHB modules are connected in series to form an AC port on one side of the AC/AC converter, the AC output terminals of N1 CHB modules are connected in series to form the AC port on the other side of the AC/AC converter, the AC input terminals of N−N1 full-bridge rectifiers are connected in series to form the AC port of the AC/DC module, the AC port on one side of the AC/AC converter is connected in series with the AC side port of the AC/DC module and then connected to a first AC network nd the AC port on the other side of the AC/AC converter is connected in series with the DC side port of the AC/DC module.