Converter Controller Grid Fault Ride-Through

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional power conditioners and converters struggle to effectively ride through grid fault events, often resulting in shutdowns and restarts due to overvoltage conditions, which can cause damage to components and reduce their lifespan.

Innovation Solution

A power module with a controller that detects grid fault events by monitoring voltage and disabling the converter to prevent overvoltage conditions, allowing the system to ride through faults while minimizing shutdowns and extending component lifespan.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If braking resistors are used to absorb excessive energy during grid fault events, then overvoltage conditions are reduced, but device complexity and energy loss increase

Engineering Contradiction:
Improveprotection from overvoltage conditionsVSAvoidinclusion of braking resistors
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent removes the braking resistor component from the system entirely. Instead of using passive energy dissipation through resistors, the invention uses active control of the converter switching devices to manage energy flow during grid faults, thereby achieving overvoltage protection without the added complexity and energy loss associated with braking resistors

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the operational parameters of the converter by dynamically adjusting the switching devices' operation modes during grid fault events. By transitioning between different switching states and controlling the energy flow parameters, the system can ride through faults without requiring additional protective components like braking resistors

Inventive Principle:
Principle #35Parameter changes

2Reliability

If switching devices are instantaneously turned OFF during grid fault events, then overvoltage conditions are prevented, but productivity decreases due to shutdown and restart

Engineering Contradiction:
Improveprevention of overvoltage conditionsVSAvoidcontinuous power generation
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent implements dynamic control of the converter during grid fault events rather than instantaneous shutdown. The switching devices are controlled to transition smoothly between operating states, allowing the system to adapt its behavior in real-time based on fault conditions while maintaining continuous operation and avoiding complete shutdowns

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent enables the converter to continue performing its power conversion function during grid fault events by maintaining controlled operation of the switching devices. This continuous operation allows the independent source to remain connected and potentially provide support during faults, eliminating the need for shutdown and restart cycles

Inventive Principle:
Principle #20Continuity of useful action

3Productivity

If converter remains operational during grid fault events, then productivity is maintained, but overvoltage conditions may damage components

Engineering Contradiction:
Improvecontinuous power generationVSAvoidovervoltage damage to components
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent employs feedback control mechanisms that continuously monitor grid conditions and converter operation during fault events. Based on this feedback, the control system dynamically adjusts the switching devices to maintain safe operating voltages while continuing power generation, thereby preventing overvoltage damage without requiring shutdown

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP2771957B1Systems and methods for using in recovering converter after grid fault event
Publication Date: 2018.06.20 GENERAL ELECTRIC CO
  • EP2771957B1 patent drawingFigure 1
  • EP2771957B1 patent drawingFigure 2
  • EP2771957B1 patent drawingFigure 3

AI summary

Systems, power modules (108), and methods (200) for using in controlling a converter (110) coupled between a power generator (104) and an electric grid (102) are provided. One of the power modules (108) includes the converter (110) configured to supply an output from the power generator (104) to the electric grid (102), and a controller (112) coupled to the converter (110). The controller (112) includes a phase-lock-loop (PLL) module (123) and at least one regulator (128, 130). The at least one regulator (128, 130) is configured to at least partially control the converter (110) as a function of at least one parameter. The controller (112) is configured to disable the converter (110) in response to a grid fault event, to maintain coupling between the power generator (104) and the converter (110) during the grid fault event, to determine whether the PLL module (123) is locked onto a voltage associated with the electric grid, to adjust the at least one parameter after the grid fault event, and to re-enable the converter to supply the output from the power generator (104) to the electric grid (102).