Rail Vehicle Battery Charging via Network Frequency Modulation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Charging stations for battery-hybrid rail vehicles on non-electrified tracks often face limitations due to insufficient power supply from local grids, necessitating the active limitation of charging power, especially when multiple vehicles charge simultaneously, which can lead to network overload.

Innovation Solution

A method involving frequency analysis of the charging network to dynamically determine charging power levels, allowing for situation-dependent and individual power allocation based on the presence and status of other vehicles, combined with modulated charging power to communicate and distribute power efficiently.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If multiple rail vehicles charge simultaneously at the charging station, then the charging capacity utilization is improved, but the network overload risk increases

Engineering Contradiction:

Improvecharging capacity utilizationVSAvoidnetwork overload risk

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The charging power is made dynamic through frequency modulation. Each rail vehicle modulates its charging current at a unique frequency, allowing the charging station to dynamically identify and manage power distribution to multiple vehicles simultaneously based on network capacity, preventing overload while maximizing utilization.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the parameter of charging current by modulating it at different frequencies for different rail vehicles. This frequency-based parameter change enables the charging station to distinguish between multiple vehicles and allocate power appropriately, resolving the contradiction between simultaneous charging and network overload prevention.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the charging power is actively limited to prevent network overload, then the network stability is improved, but the charging efficiency decreases

Engineering Contradiction:

Improvenetwork stabilityVSAvoidcharging efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The charging station continuously monitors the charging network for frequency modulations from multiple rail vehicles. This feedback mechanism allows the station to identify connected vehicles and their charging status, enabling dynamic power allocation that maintains network stability while optimizing charging efficiency by avoiding unnecessary power limitations.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

Each rail vehicle independently modulates its charging current at its own unique frequency, effectively identifying itself to the charging station. This self-service approach allows vehicles to actively participate in power management, enabling the station to allocate power efficiently without excessive limiting while maintaining network stability.

Inventive Principle:

Principle #25Self-service

3Measurement precision

If frequency analysis is performed to identify other rail vehicles, then the power distribution accuracy is improved, but the system complexity increases

Engineering Contradiction:

Improvepower distribution accuracyVSAvoidsystem complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex communication infrastructure with electrical frequency analysis. Instead of using separate communication channels to identify and manage multiple rail vehicles, the system uses the existing charging current as a communication medium by modulating it at unique frequencies, simplifying the overall system while improving power distribution accuracy.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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

Enables flexible and overload-free charging by accounting for network load, ensuring optimal power distribution and communication between vehicles, enhancing charging efficiency and stability.

Implementation Method 1

a frequency analysis is performed in the charging network of the charging station, in particular on the charging current or the network voltage

Methodology Applied

Scientific EffectFrequency analysis:

Implementation Method 2

The frequency analysis can be performed, for example, by means of a Fourier analysis of the charging power or the network voltage

Methodology Applied

Scientific EffectFourier analysis:

Implementation Method 3

a charging power that is essentially at the determined charging power level is modulated with at least one predetermined frequency

Methodology Applied

Scientific EffectPower modulation:

Data Source

PatentEP4711186A1Power modulation-based charging of a battery of a rail vehicle

Publication Date: 2026.03.18 SIEMENS MOBILITY GMBH

Figure 1
Figure 2
Figure 3

AI summary

The present invention relates to a method (100; 200) for charging at least one battery (22) of a rail vehicle (20; 40) at a charging station (10), as well as to a rail vehicle (20; 40) and a system (50). In the method (100), the rail vehicle (20) is electrically connected (S1) to a charging network (12) of the charging station (10). Furthermore, a frequency analysis is performed in the charging network (12) (S2), and a charging power level (P_L) is determined based on the frequency analysis (S3). Finally, the battery (22) is charged with a charging power (P_N) (S4) that is essentially at the determined charging power level (P_L).