Parallel Path DC-DC Converter for Automotive Drive Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
DC-DC converters in automotive systems experience significant conduction losses when operating to increase or decrease input voltage, affecting the drive range and fuel economy of vehicles.
Innovation Solution
Incorporating parallel current paths with an inductor and switches, where the first switch is connected between the inductor and a second switch, allowing current to bypass the inductor and reduce conduction losses by using parallel paths between the traction battery and inverter.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If DC-DC converter uses conventional series configuration with inductor and switches, then voltage conversion function is achieved, but conduction losses increase significantly
Solution Approach 1:
The DC-DC converter is segmented into multiple parallel current paths, each containing switches and inductors. This segmentation allows the converter to distribute current flow across multiple paths, reducing conduction losses in any single path while maintaining the overall voltage conversion function.
Solution Approach 2:
The converter topology transitions from a single-series path to a multi-dimensional parallel structure. By adding the dimension of parallel current paths, the system achieves lower conduction losses while preserving the essential buck-boost voltage conversion capability through coordinated switch operation.
2Adaptability or versatility
If DC-DC converter operates to increase or decrease input voltage, then voltage flexibility is improved, but conduction losses worsen
Solution Approach 1:
The converter employs dynamic switch control to adaptively select and configure active current paths based on operating conditions. During voltage increase mode, certain parallel paths are activated while others remain inactive, optimizing conduction loss performance for each specific operating point while maintaining full voltage conversion flexibility.
Solution Approach 2:
The system changes operational parameters by selectively activating different parallel paths depending on whether voltage increase or decrease is required. This parameter change strategy allows the converter to maintain adaptability across different voltage conversion modes while minimizing conduction losses through optimal path selection.
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 configuration minimizes conduction losses through the DC-DC converter, improving the drive range and fuel economy of vehicles by approximately 0.2% to 1% compared to conventional systems.
Implementation Method 1
The storage may be in either magnetic field storage components (inductors, transformers) or electric field storage components (capacitors)
Implementation Method 2
The efficiency of some DC-DC converters has increased in recent decades due to the use of power field effect transistors, which are able to switch at high frequencies and more efficiently than power bipolar transistors
Data Source
AI summary
An automotive electric drive system may include an electric power source, an electric machine, and a DC-DC power converter electrically connected between the electric power source and the electric machine. The DC-DC power converter may include an inductor and a first switch each disposed in a different current path connecting the electric power source and the electric machine. The currents paths may be electrically in parallel.