Electric Energy Conversion System Voltage Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electric energy conversion systems face challenges in achieving optimal energy density from capacitive energy storage devices while maintaining transparency to transient power line disturbances and low pass filtering, often requiring complex converter architectures that lead to inefficiencies and overdimensioning of converters.
Innovation Solution
An electric energy conversion system with a main converter and a bidirectional charger, where the main converter operates to slave the storage voltage on a set value, and the bidirectional charger, with a synchronous rectifier, controls the output voltage, ensuring efficient energy transfer and filtering without overdimensioning, and includes galvanic insulation for improved performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the voltage of the intermediate network is set to 100 volts to optimize energy density of capacitive energy storage devices, then the energy density is improved, but the final converters become overdimensioned and yield deteriorates
Solution Approach 1:
The patent divides the energy storage function into two separate networks: an intermediate network operating at optimized voltage for energy storage (100V for aluminium electrolytic capacitors) and an output network operating at voltage optimized for final converters (e.g., 28V). This segmentation allows each network to operate at its optimal voltage level without compromising the other, resolving the contradiction between energy density and converter efficiency.
2Productivity
If the voltage of the intermediate network is reduced to 35 volts to improve yield of final low voltage converters, then the converter yield is improved, but the energy density of the capacitive energy storage device deteriorates
Solution Approach 1:
The patent creates separate operational domains for energy storage and power conversion by implementing an intermediate network at higher voltage (optimized for energy density) and an output network at lower voltage (optimized for final converter yield). The bidirectional charger acts as a bridge between these segmented networks, allowing each to operate independently at its optimal voltage level.
3Quantity of substance
If a bidirectional charger is added to enable energy storage at optimal voltage, then the energy density is improved, but the device complexity increases
Solution Approach 1:
The bidirectional charger is designed to perform multiple functions: it charges the energy storage network during normal operation, discharges to the output network during transient disturbances, and provides galvanic isolation. This multi-functionality reduces the need for separate dedicated components for each function, thereby limiting the increase in overall system complexity despite the addition of the charger.
4Power
If the primary converter is overdimensioned to provide constant power output over the whole range of output voltages, then the power delivery capability is improved, but the device complexity and cost increase
Solution Approach 1:
The patent segments the power conversion function between the main converter and the bidirectional charger. The main converter operates at constant power mode during normal operation, while the bidirectional charger handles transient power delivery during disturbances. This segmentation allows each converter to be optimally dimensioned for its specific function, avoiding the need for one oversized converter to handle all scenarios.
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 allows for optimal use of capacitive energy storage devices, efficient filtering of high-frequency current requests, and reduced complexity in the energy conversion chain, maintaining system stability and efficiency across varying voltage ranges.
Implementation Method 1
a bidirectional charger (46) connected to said output network (42) on the one hand and to capacitive means for storing electric energy (48) on the other hand
Implementation Method 2
the voltage of which varies within a range between a first voltage value corresponding to a full charging state of the means for storing electric energy (47) and a second voltage value corresponding to an empty charging state of the means for storing electric energy (47)
Implementation Method 3
The bidirectional charger includes a synchronous rectifier controlled in a peak current mode
Data Source
AI summary
This electric energy conversion system of the type including a main converter (40) connected at the input to at least one input network (41) operating under an input voltage and at the output to an output network (42) operating under an output voltage and associated with an electric energy storage device, operating under a storage voltage, including a bidirectional charger (46) connected to the output network (42) on the one hand and to capacitive electric energy storage means (48) on the other hand, the operation of the bidirectional charger (46) being driven by control means (49) for slaving the output voltage on a first set value (Vref2), is characterized in that the operation of the main converter (40) is driven by control means (50) for slaving the storage voltage on a second set value (Vref1).