No Break Power Transfer for Variable Frequency Generators

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In variable frequency power generating systems, transferring power between generators operating at different frequencies often results in momentary interruptions, leading to high inrush currents when loads are re-energized, which can damage generators and require larger equipment to handle the surge.

Innovation Solution

A power transfer device with a voltage matching/synchronization control module that synchronizes power output to match the voltage and frequency of either bus, allowing for a controlled no-break power transfer by closing a tie switch between the buses, thereby reducing or eliminating inrush currents.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If break power transfer is used to transfer power between generators operating at different frequencies, then generator damage is prevented, but momentary power interruption occurs causing high inrush currents

Engineering Contradiction:

Improvegenerator protectionVSAvoidinrush current

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

A power transfer device is introduced as an intermediary between the first and second buses. This device includes synchronization control modules that match the voltage and frequency of the source bus to the target bus before closing the tie switch, enabling seamless power transfer without interruption or inrush currents while protecting the generators

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The synchronization control modules perform preliminary voltage and frequency matching before the actual power transfer occurs. The system pre-adjusts the power output of the power transfer device to match the target bus parameters, and only after synchronization is achieved does it close the tie switch, preventing harmful inrush currents

Inventive Principle:

Principle #10Preliminary action

2Power

If larger generators and contactors are used to handle inrush current, then power transfer capability is improved, but system complexity and cost increase

Engineering Contradiction:

Improveinrush current handling capabilityVSAvoidsystem equipment size

Core Design Contradiction:

PowerVSDevice complexity

Solution Approach 1:

The power transfer device acts as a mediator that eliminates the need for oversized generators and contactors by preventing inrush currents through synchronization and sequential switching, allowing standard-sized equipment to handle power transfers smoothly

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If de-energizing the bus is performed to transfer power between different frequency generators, then generator damage is prevented, but power continuity is interrupted

Engineering Contradiction:

Improvegenerator protectionVSAvoidpower interruption duration

Core Design Contradiction:

ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The power transfer device maintains continuous power supply to the load by using multiple input sources and sequential switching. While one generator is transferring power through synchronization, the other generator continues to supply power, ensuring no interruption in the useful action of powering the load

Inventive Principle:

Principle #20Continuity of useful action

Solution Approach 2:

The power transfer device serves as an intermediary that enables seamless power transfer by synchronizing voltage and frequency before closing the tie switch, eliminating the need to de-energize the bus and maintaining continuous power delivery

Inventive Principle:

Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution enables a controlled no-break power transfer, reducing or eliminating inrush currents and preventing damage to generators and loads, while maintaining power continuity during the transfer process.

Implementation Method 1

a rectifier/filter module connected to the input switch

Methodology Applied

Scientific EffectRectification: Diode

Implementation Method 2

a rectifier/filter module connected to the input switch

Methodology Applied

Scientific EffectFiltering: Filter (electronic)

Implementation Method 3

an inverter connected to the rectifier/filter module, the inverter being controlled by the voltage matching/synchronization control module

Methodology Applied

Scientific EffectInversion:

Data Source

PatentUS8928179B2No break power transfer for power generating system

Publication Date: 2015.01.06 HAMILTON SUNDSTRAND CORP

AI summary

A method for no break power transfer in a variable frequency power generating system, the power generating system comprising a first bus connected to a first generator and a second bus connected to a second generator includes configuring a power transfer device to output power that is synchronized to match a voltage and a frequency of the second bus to the second bus; reconfiguring the power transfer device to output power that is synchronized to match a voltage and a frequency of the first bus to the second bus; and closing a tie switch located between the first bus and the second bus.