Train Air Conditioner Temperature Control for Regeneration Loss Reduction

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Solution Overview

Problem

Conventional train-information management systems fail to effectively utilize regenerated power generated during regenerative braking due to the lack of a controlled destination for the electric power, leading to regeneration loss when no other trains are nearby to consume it.

Innovation Solution

A train-information management device that includes a position detection unit, a regenerating-condition detection unit, a train-line information holding unit, and a target-temperature control unit, which adjusts the air conditioner's temperature set value based on the train's position and regenerative braking conditions to increase power consumption and reduce regeneration loss.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If the train uses a regenerative brake to generate electric power, then the braking efficiency is improved, but the regenerated power cannot be effectively used when no other trains are nearby to consume it, causing regeneration loss

Engineering Contradiction:
Improveregeneration lossVSAvoidpower consumption adaptability
Core Design Contradiction:
Loss of energyVSAdaptability or versatility

Solution Approach 1:

The system performs preliminary action by detecting the train's position and predicting future braking needs before they occur. The position detection unit identifies when the train is approaching a section where braking is likely required, and the control unit pre-adjusts the air conditioner's target temperature to create a power consumption opportunity that will be ready when regenerative braking occurs.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements feedback by continuously monitoring the train's position, braking conditions, and power generation status. The regenerative brake detection unit provides feedback on whether the train is currently regenerative braking, and this information feeds back to the control unit to dynamically adjust the air conditioner's target temperature in real-time, ensuring optimal power utilization.

Inventive Principle:
Principle #23Feedback

2Use of energy by moving object

If the air conditioner target temperature is constantly adjusted to maximize power consumption, then regenerated power utilization is improved, but the passenger comfort and temperature stability deteriorate

Engineering Contradiction:
Improvepower consumptionVSAvoidtemperature stability
Core Design Contradiction:
Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The system applies partial action by making small, controlled adjustments to the air conditioner's target temperature rather than drastic changes. The control unit adds or subtracts a predetermined value from the set temperature, creating just enough power consumption demand to utilize regenerative power without excessively deviating from the comfortable temperature range for passengers.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The system uses periodic action by adjusting the target temperature in discrete steps based on detected regenerative braking conditions. Rather than continuous adjustment, the control unit periodically modifies the target temperature when specific conditions are met (when regenerative braking is detected or predicted), allowing the system to respond to power generation opportunities while maintaining overall temperature stability.

Inventive Principle:
Principle #19Periodic action

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 system effectively uses the regenerated power by increasing electric power consumption during regenerative braking, reducing the likelihood of regeneration loss and enabling more efficient use of the generated power, even when other trains require only a small amount of electric power.

Implementation Method 1

a power conversion device 6 that converts electric power supplied from an overhead wire 100 and then supplies the converted power to the motor 7 and to an auxiliary device 9

Methodology Applied
Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Implementation Method 2

the motor 7 and then returns the electric power generated during the braking back to the overhead wire 100

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP2886386B1Train-information management device and device control method
Publication Date: 2017.09.27 MITSUBISHI ELECTRIC CORP
  • EP2886386B1 patent drawingFigure 1
  • EP2886386B1 patent drawingFigure 2~3
  • EP2886386B1 patent drawingFigure 4

AI summary

The present invention includes a position detection unit 11; a regenerating-condition detection unit 13 that detects a condition in which the regenerative-brake is used; a train-line information holding unit 14 that holds therein information on a section in which a train is more likely to use a brake; an air-conditioning set-value holding unit 15 that holds therein a temperature set value of an air conditioner; and a target-temperature control unit 12 that decides a target temperature that is designated to the air conditioner. In a regeneration-preparation condition in which a train is running through a position at which the distance between the position and a section in which a train is more likely to use a brake is equal to or less than a given value and in which the train does not use a regenerative brake, the target-temperature control unit 12 decides a value, generated by adding a predetermined value to the temperature set value, as the target temperature. In a regenerating condition in which the train uses a regenerative brake, the target-temperature control unit 12 decides a value, generated by subtracting a predetermined value from the temperature set value, as the target temperature. In a normal condition that is neither the regeneration-preparation condition nor the regenerating condition, the target-temperature control unit 12 decides the temperature set value as the target temperature.