DC-DC Converter Phase Balancing via Capacitor Internal Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-power DC/DC converters with multiple phases face asymmetry issues due to component tolerances and electrical oscillations, leading to increased complexity, power loss, and reduced efficiency, which complicates current measurement and load distribution.
Innovation Solution
A method using a capacitor with internal resistance to balance phases by evaluating voltage ripples across the series connection, allowing for indirect current measurement and load distribution optimization, reducing the complexity and cost of components and installation space.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a current measurement module is installed in each phase to detect asymmetry, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent merges the current measurement function into the existing capacitor component by utilizing its internal resistance. Instead of adding separate measurement modules to each phase, the solution combines measurement capabilities with the capacitor that already exists in the circuit, thereby reducing device complexity while maintaining measurement precision through voltage ripple evaluation across the capacitor's internal resistance.
Solution Approach 2:
The capacitor is given multiple functions: it serves both as a filtering component and as a measurement element. By evaluating the voltage ripple across the capacitor's internal resistance, the same component performs both its traditional electrical function and the additional function of current measurement, eliminating the need for dedicated measurement hardware in each phase.
2Measurement precision
If a current measurement module is installed in each phase, then measurement precision is improved, but power loss increases
Solution Approach 1:
The measurement function is merged into the existing capacitor structure, eliminating the need for additional active measurement components in each phase. This reduces the total power consumption of the system while maintaining the ability to accurately detect current asymmetry through voltage ripple evaluation across the capacitor's internal resistance.
Solution Approach 2:
The capacitor's internal resistance, which is an inherent property of the component, is utilized for measurement purposes. The system uses the capacitor's own characteristics (its internal resistance) to perform current measurement, eliminating the need for external measurement devices that would consume additional power.
3Measurement precision
If a current measurement module is installed in each phase, then measurement precision is improved, but manufacturing cost increases
Solution Approach 1:
The solution merges measurement functionality into the existing capacitor component, eliminating the need to manufacture and assemble separate measurement modules for each phase. This reduces manufacturing complexity and cost while maintaining measurement precision through the evaluation of voltage ripple across the capacitor's internal resistance.
Solution Approach 2:
The capacitor serves multiple functions including filtering and current measurement. This multi-functionality reduces the total component count and simplifies the manufacturing process, as the same component performs both traditional electrical functions and measurement tasks, thereby reducing overall manufacturing cost.
4Device complexity
If phase asymmetry is not addressed, then device complexity is reduced, but reliability deteriorates
Solution Approach 1:
The system implements feedback by continuously evaluating the voltage ripple across the capacitor's internal resistance to detect phase asymmetry. This feedback mechanism allows the system to monitor phase balance and take corrective actions, thereby maintaining reliability without adding complex measurement modules to each phase.
Solution Approach 2:
The capacitor's internal resistance serves as an intermediary element that enables phase asymmetry detection. By measuring the voltage ripple across this internal resistance, the system can indirectly detect current asymmetry and phase imbalance, maintaining reliability through a simple and integrated measurement approach.
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 reduces the complexity and cost of components, minimizes power loss, and enhances efficiency by achieving symmetrization of phases through software-controlled duty cycle adjustments, resulting in improved load distribution and reduced resource expenditure.
Implementation Method 1
a capacitor (28) with an internal resistance (30), wherein the capacitor (28) and the internal resistance (30) form a series circuit
Implementation Method 2
a voltage drop occurs at the series connection of the capacitor (28) and the internal resistance (30), which results from the superimposition of the individual currents of the individual converters (20, 22)
Data Source
Figure 1a
Figure 1b
Figure 2
AI summary
The invention relates to a method for adjusting a polyphase DC-DC converter (18) comprising at least two single converters (20, 22) and, at an interface, a capacitor (28) having an internal resistor (30), the capacitor and the resistor being connected in series. According to said method, in accordance with a sequence one of the single converters (20, 22) provides a current which flows through the capacitor (28) and the resistor (30) and a voltage drops at the series connection, said drop resulting from the superposition of the individual currents of the single converters (20, 22) and being measured.