Vehicle Converter Control for Resonance Damping on External Power Links
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing control systems for vehicles receiving power from external sources, such as catenary lines, face link oscillations and instability due to inductive-capacity input filtering and transients, which can lead to breaker tripping and require protective circuits, and existing active dampening strategies are insufficient for unknown or varying component and controller conditions.
Innovation Solution
A method and system that determines the resonant frequency of a vehicle system coupled with an external power source, forming stabilizing voltage and current components using filters, and generates a control input to change the resonant frequency by communicating these components with a converter device, thereby stabilizing the link between the vehicle and the external power source.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If inductive-capacitive filter is used to dampen transient effects, then connection stability is improved, but link oscillations occur when natural frequency is excited
Solution Approach 1:
The system dynamically changes the resonant frequency parameter of the power link by adjusting converter control inputs based on detected oscillation characteristics. When oscillations are detected, the controller modifies operating parameters (such as switching frequency or pulse width modulation duty cycle) to shift the resonant frequency away from the excitation frequency, thereby eliminating the oscillation condition while maintaining connection stability.
Solution Approach 2:
The system implements a feedback mechanism where voltage and current sensors continuously monitor the power link for oscillations. The controller processes this feedback information, detects resonant conditions, and automatically adjusts converter control inputs to change the resonant frequency. This closed-loop feedback ensures that connection stability is maintained while dynamically responding to and eliminating link oscillations.
2Stability of the object's composition
If existing active dampening control strategies are used, then known resonant frequencies are suppressed, but adaptability to unknown or varying conditions is insufficient
Solution Approach 1:
The system employs self-service by automatically detecting its own resonant frequency characteristics through voltage and current monitoring. Rather than relying on pre-programmed frequency values, the controller performs real-time analysis of the power link's electrical characteristics to identify actual resonant conditions. This self-detection capability enables the system to adapt to unknown or varying component conditions without external intervention, suppressing resonant frequencies while maintaining adaptability to changing operating conditions.
3Stability of the object's composition
If converter control inputs are adjusted to change resonant frequency, then link oscillations are reduced, but additional control complexity is introduced
Solution Approach 1:
The controller performs multiple functions using a unified approach: it monitors voltage and current for oscillation detection, analyzes frequency characteristics to identify resonant conditions, and adjusts converter control inputs to eliminate oscillations. By combining these functions into a single multi-functional control algorithm, the system reduces overall control complexity compared to having separate dedicated circuits for each function, while still achieving effective oscillation reduction through resonant frequency modification.
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 approach effectively dampens resonant frequencies, reducing oscillations and instability, and can adapt to unknown or varying conditions, enhancing the stability of the vehicle system's power connection.
Implementation Method 1
A first filter extracts one or more of a phase or a frequency component from the voltage provided by the external power source to generate the stabilizing voltage component
Implementation Method 2
A second filter extracts one or more of a phase or a frequency component from the current provided by the external power source to generate the stabilizing current component
Implementation Method 3
The stabilizing voltage component, the stabilizing current component, and the control input change the resonant frequency of the vehicle system
Implementation Method 4
This approach effectively dampens resonant frequencies, reducing oscillations and instability
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A method and system include determining a resonant frequency of a vehicle system operably coupled with an external power source that provides voltage and current to the vehicle system. A first filter extracts a phase or a frequency component from the voltage provided by the external power source to generate a stabilizing voltage component. A second filter extracts a phase or a frequency component from the current provided by the external power source to generate a stabilizing current component. The stabilizing voltage component is out of phase with the stabilizing current component. A control input of a converter device of the vehicle system is determined based on the stabilizing voltage component, the stabilizing current component, and the resonant frequency. The stabilizing voltage component, the stabilizing current component, and the control input are communicated with the converter device to change the resonant frequency of the vehicle system.