Modular Ring-Topo Controller for MMC Communication

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing power electronic converters are expensive and complex to assemble, modify, and repair due to the use of optical fibers for control signal and status information transmission, requiring time-consuming rewiring for modifications and repairs.

Innovation Solution

A power electronic converter with a control system that combines a ring network topology for the master controller and slave devices with a star network topology for local controllers, enabling wireless communication and modular design for easier modification and repair, replacing the need for optical fibers with wireless communication like Free Space Optical (FSO) or wired communication using Ethernet protocols.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If optical fibers are used for transmitting control signals and status information, then reliable communication and high voltage insulation are provided, but the converter becomes expensive and complex to assemble, modify, and repair

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidassembly complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The control system is segmented into a master controller and multiple independent slave devices. Each slave device can be independently connected to or disconnected from the ring network, allowing modular assembly and repair without affecting the entire system. This segmentation reduces assembly complexity while maintaining communication reliability through the redundant ring topology.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Slave devices act as intermediary nodes between the master controller and the power electronic switches. These intermediate nodes simplify the control architecture by distributing control functions, reducing the complexity of direct master-controller-to-switch connections while ensuring reliable signal transmission through the ring network structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If optical fibers are used for transmitting control signals and status information, then reliable communication is provided, but modification and repair require time-consuming rewiring

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidrepair ease
Core Design Contradiction:
ReliabilityVSEase of repair

Solution Approach 1:

The system is divided into modular slave devices that can be independently replaced. When repair is needed, individual slave devices can be swapped out without disturbing other parts of the system, eliminating the need for time-consuming optical fiber rewiring while maintaining communication reliability through the ring topology's inherent redundancy.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The ring network topology provides dynamic reconfiguration capability. When a slave device is removed or added, the ring automatically adapts by rerouting signals through the alternative path, enabling hot-swapping of components without system shutdown or complex rewiring, thus improving ease of repair while maintaining reliability.

Inventive Principle:
Principle #15Dynamics

3Object-affected harmful factors

If optical fibers are used for transmitting control signals and status information, then electric isolation is provided, but the converter is difficult to modify for new functions

Engineering Contradiction:
Improveelectric isolationVSAvoidfunction adaptability
Core Design Contradiction:
Object-affected harmful factorsVSAdaptability or versatility

Solution Approach 1:

The control system is segmented into independent slave devices that can be selectively added or removed based on functional requirements. This modular approach allows the converter to be easily adapted for new functions by simply connecting or disconnecting specific slave devices, maintaining electric isolation through the optical interface while significantly improving adaptability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The slave devices are designed as universal modular units that can perform different control functions depending on their configuration and connection to the ring network. This multi-functionality allows the same hardware platform to support various converter configurations and new functions without requiring physical rewiring, while electric isolation is maintained through the optical communication interface.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP2897268B1Master/slave controller system in ring topology for modular multilevel converters
Publication Date: 2022.01.05 ABB (SCHWEIZ) AG
  • EP2897268B1 patent drawingFigure 1a~1b
  • EP2897268B1 patent drawingFigure 2
  • EP2897268B1 patent drawingFigure 3

AI summary

A power electronic converter (1) for converting electric energy and a method for controlling a power electronic converter. The converter comprises a plurality of PE switches (10), and a control system (12) adapted to transmit control information to the PE switches. The control system comprises a master controller (14) and a plurality of local controllers (18) controlling the PE switches. The control system further comprises one or more slave devices (16) controlled by the master controller. The control system (12) is configured so that the master controller (14) and the one or more slave devices are connected in a ring network topology. Each slave device and one or more of the local controllers are connected in a star network topology.