DC-DC Converter Control Without Current Sensors in Fast Charging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing direct current fast charging (DCFC) systems rely on current sensors to improve dynamic performance, which can be cumbersome and less efficient, especially under varying load and battery conditions.
Innovation Solution
A controller module for the DC-DC converter that estimates output current without using current sensors, generating control signals based on input and output voltages to regulate charging output, enabling efficient power conversion and dynamic response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If current sensors are used to improve dynamic performance, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent removes current sensors from the system entirely, extracting the measurement function from physical sensing hardware and implementing it through computational estimation using voltage measurements and system parameters, thereby reducing device complexity while maintaining measurement capability
Solution Approach 2:
The patent replaces the physical current sensing mechanism with an electrical/virtual sensing approach, using voltage measurements combined with system modeling to estimate current, substituting mechanical/electrical sensor hardware with computational methodology
2Reliability
If current sensors are used to improve dynamic performance, then reliability is improved, but ease of manufacture worsens
Solution Approach 1:
By removing current sensors from the system, the patent simplifies the manufacturing process, reducing the number of components that need to be sourced, assembled, and calibrated, while maintaining reliability through alternative computational measurement methods
3Device complexity
If voltage-based control is used to reduce system complexity, then device complexity is reduced, but measurement precision may worsen
Solution Approach 1:
The patent implements feedback control using voltage measurements, where the controller continuously monitors output voltage and adjusts control signals based on the difference between actual and reference voltage values, improving the precision of current estimation through closed-loop control
Solution Approach 2:
The patent changes the measurement parameter from direct current sensing to voltage sensing combined with computational estimation, transforming the measurement approach to use more readily available voltage signals and system parameters to derive current information
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 solution enhances the dynamic performance and efficiency of DCFC systems by eliminating the need for current sensors, improving adaptability to varying load conditions and reducing system complexity.
Implementation Method 1
an AC-DC converter configured to generate an input DC voltage Vin in response to a received grid AC voltage
Implementation Method 2
a DC-DC converter configured to generate an output DC voltage Vo in response to the input voltage Vin
Data Source
AI summary
Various disclosed embodiments include illustrative controller modules, direct current (DC) fast charging devices, and methods. In an illustrative embodiment, a controller module for a DC-DC converter includes a controller and computer-readable media configured to store computer-executable instructions configured to cause the controller to receive an input voltage Vin to the DC-DC converter, receive an output DC voltage Vo from the DC-DC converter, generate control signals configured to control a charging output of the DC-DC converter responsive to the received input voltage Vin and output voltage Vo, and output the generated control signals to the DC-DC converter.