Reactor Temperature Testing via Segmented Current Simulation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional temperature increase testing methods for reactors either result in large-scale testing circuits or fail to accurately simulate the frequency-dependent copper and iron losses when harmonic currents are superimposed on fundamental wave currents.

Innovation Solution

A temperature increase testing method that calculates target copper and iron losses based on measurements during energization of fundamental and harmonic currents, and then adjusts the test frequency and current value to simulate these losses in a reactor, allowing for a simpler testing circuit.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional test X superimposes fifth harmonic current onto rated current to simulate actual usage conditions, then the test corresponds to actual usage conditions, but currents mix into fundamental wave power supply and harmonic power supply making the testing circuit complex and large in scale

Engineering Contradiction:
Improvetest accuracyVSAvoidtesting circuit complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts the harmonic current component from the mixed power supply system and applies it separately to the reactor under test. By using a test circuit that supplies fundamental wave current and harmonic current through separate paths, the method eliminates current mixing between power supplies while maintaining accurate simulation of actual usage conditions where harmonic currents are present

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The testing method segments the current supply into separate fundamental wave current supply and harmonic current supply components. This segmentation allows independent control and measurement of each current component, preventing mixing issues while accurately reproducing the superimposed current conditions that occur in actual reactor operation

Inventive Principle:
Principle #1Segmentation

2Device complexity

If conventional test Y supplies total loss with fundamental wave current only, then the testing circuit is simpler, but the copper loss and iron loss in the state where fundamental wave and harmonic are superimposed are not accurately simulated

Engineering Contradiction:
Improvetesting circuit complexityVSAvoidloss simulation accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The invention changes the frequency parameter of the test current to match the harmonic frequency present in actual operation. By energizing the reactor with harmonic current at the appropriate frequency (e.g., 5th harmonic at 5 times the fundamental frequency), the method accurately simulates the frequency-dependent copper loss and iron loss that occur when harmonic currents are superimposed on the fundamental wave in actual usage conditions

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The testing method dynamically adjusts the test conditions to reflect actual operating scenarios. Instead of using fixed fundamental wave current, the method applies variable frequency current that matches the harmonic content of actual operation, allowing accurate simulation of how copper loss and iron loss change with frequency when harmonics are present

Inventive Principle:
Principle #15Dynamics

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

This method enables a more accurate simulation of actual usage conditions for reactors, reducing the complexity of the testing circuit and ensuring that the test conditions reflect the true losses experienced during operation.

Implementation Method 1

copper loss during energization of a fundamental wave current... and respective copper losses during energization of respective harmonic currents

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 2

iron loss during energization of the fundamental wave current and iron losses during energization of the respective harmonic currents

Methodology Applied
Scientific EffectIron loss: Hysteresis

Data Source

PatentEP4266067B1Temperature increase testing method for reactors
Publication Date: 2025.05.14 NISSIN ELECTRIC CO LTD
  • EP4266067B1 patent drawingFigure 1
  • EP4266067B1 patent drawingFigure 2
  • EP4266067B1 patent drawingFigure 3~4

AI summary

This temperature increase testing method for reactors comprises a step for supplying, to a reactor, a test current having a test frequency and a test current value which apply a target copper loss (Wcut) that is based on copper loss (Wcu21) when a fundamental wave current is supplied and copper loss (Wcu22) when a harmonic wave current is supplied, and a target iron loss (Wfet) that is based on iron loss (Wfe21) when a fundamental wave current is supplied and iron loss (Wfe22) when a harmonic wave current is supplied.