Interleaved DC-DC Boost Converter with Coupled Inductors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional DC-DC converters face challenges in managing high voltages and currents while maintaining power density and efficiency, particularly in applications like photovoltaic systems and energy storage, where they often result in increased circulating currents and larger inductor sizes.
Innovation Solution
The proposed DC-DC power converter employs a configuration with interleaved phase legs, including a filter portion with inductors at the low-voltage input, a DC-DC converter portion with sets of switches, a DC-link portion with capacitors, and a coupled inductor portion at the high-voltage output, featuring coupled inductors in series with the initial inductors to reduce circulating currents and ripple, thereby enhancing efficiency and power density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If conventional DC-DC converters are used to handle high voltages and currents, then power conversion capability is improved, but circulating currents increase and inductor sizes become larger
Solution Approach 1:
The converter is divided into multiple interleaved phases (first and second sets of switches with associated inductors), where each phase handles a portion of the total power. This segmentation distributes the current burden across multiple smaller inductors rather than requiring one large inductor, thereby reducing the size of individual inductors while maintaining the overall power conversion capability.
2Power
If conventional DC-DC converters are used to handle high voltages and currents, then power conversion capability is improved, but circulating currents increase
Solution Approach 1:
The interleaved phases operate with periodic switching patterns, where the first and second sets of switches are activated in alternating sequences. This periodic action causes the ripple currents from different phases to cancel each other out, significantly reducing the circulating currents and associated energy losses while maintaining high power conversion capability.
3Power
If larger inductors are used to handle high currents, then power conversion capability is improved, but device complexity and cost increase
Solution Approach 1:
Instead of using fewer large inductors, the design segments the inductance requirement into multiple smaller inductors arranged in interleaved phases. This segmentation simplifies the individual component specifications and reduces overall device complexity while achieving the same power handling capability through distributed architecture.
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 reduces circulating currents and ripple, allowing for smaller, less costly inductors and improved power converter efficiency, achieving higher power density and reduced size compared to conventional systems.
Implementation Method 1
a coupled inductor portion coupled to the DC-link portion at a high voltage output of the DC-DC power converter, comprising a second set of coupled inductors, each coupled inductor of the second set of coupled inductors electrically in series with a respective inductor of the first set of inductors
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An interleaved DC-DC boost converter (291) is disclosed. The DC-DC converter (291) includes a filter portion (292) comprising first set of inductors (221) at a low voltage input (211) of the DC-DC power converter (291), a DC-DC converter portion (200) having a first and a second set of switches (251, 252) coupled to the filter portion (292), and a DC-link portion (293) coupled to the DC-DC converter portion (200), comprising a first and a second set of capacitors (231, 232). The DC-DC boost converter (291) further includes a coupled inductor portion (220) coupled to the DC-link portion (293) at a high voltage output (212) of said power converter (291), comprising a second set of coupled inductors (222, 223), each coupled inductor (222a, 222b) of the second set of coupled inductors (222) electrically in series with a respective inductor (221a, 221b)of the first set of inductors (221).