Inductive Element for Multi-Phase Power Supply Ripple Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multi-phase, interleaved power supplies face issues with varying magnetizing inductances and sub-harmonic oscillations due to non-adjacent winding cross-coupling, leading to increased output current ripple and efficiency losses.
Innovation Solution
The use of a magnetic core with distinct portions of high and low magnetic reluctance, where phase windings are arranged around low reluctance areas adjacent to high reluctance areas, and loop windings are serially coupled in a closed loop to achieve phase-independent coupling, reducing ripple and oscillations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If small value inductors are used to handle high rate of current change, then transient response is improved, but output current ripple increases and conversion efficiency decreases
Solution Approach 1:
The power supply is divided into multiple phases with separate inductors for each phase. By distributing the total inductance across multiple smaller inductors operating in parallel, each inductor can use a smaller value to achieve fast transient response while the combined effect maintains lower output ripple through phase interleaving.
Solution Approach 2:
Multiple phases are operated with periodic time shifts (interleaved switching). Each phase switches at a different time within the overall switching cycle, causing their ripple currents to partially cancel each other out when combined, thereby reducing total output ripple while maintaining fast transient response.
2Area of stationary object
If multiple smaller inductance devices are used instead of a single larger device, then space availability is improved, but output current ripple increases
Solution Approach 1:
The single large inductor is segmented into multiple smaller inductors, each handling a portion of the total current. This segmentation reduces the space required for each individual component while the phased operation of these segments produces ripple cancellation effects that reduce overall output current ripple.
Solution Approach 2:
Multiple smaller inductors are combined in parallel with phase interleaved operation. The magnetic fields and current ripples from each inductor are merged in such a way that the ripples cancel each other out, producing a smoother combined output current while utilizing less total space than a single large inductor.
3Adaptability or versatility
If windings are cross-coupled between non-adjacent positions on magnetic core, then phase-independent coupling is achieved, but varying magnetizing inductances cause sub-harmonic oscillation
Solution Approach 1:
Each winding is positioned at a specific location on the magnetic core with locally optimized coupling characteristics. The magnetic core structure provides different local magnetic paths for each phase, ensuring that each phase experiences consistent magnetizing inductance while maintaining phase-independent coupling through the distributed winding arrangement.
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 results in reduced output current ripple, improved transient response, and minimized winding losses, providing a more stable and efficient multi-phase power supply.
Implementation Method 1
The inductive element includes a magnetic core that has one or more distinct portions of relatively-high magnetic reluctance. The distinct portion(s) of relatively-high magnetic reluctance is/are, further, completely surrounded by portions of relatively-low magnetic reluctance.
Implementation Method 2
As current is driven through the windings 14 and 16, magnetic flux is produced. The magnetic flux travels outside and around the magnetic core 15, inducing current to flow through the magnetic core 15.
Data Source
AI summary
An inductive element for transforming and/or regulating voltage input from a multi-phase, interleaved power supply system into an output voltage to a load is disclosed. The multi-phase, interleaved power supply system includes a plurality of pulsed power sources, each of which is adapted to provide voltage at a discrete phase. The inductive element includes a magnetic core having, for each power supply, a distinct area of relatively-high magnetic reluctance, which is surrounded by areas of relatively-low magnetic reluctance, and a pair of windings. Each of the pair of windings includes a first, phase winding that is electrically coupled to an output of one of the pulsed power source and to the load, and a second, loop winding that is operatively coupled and proximate to the first, phase winding. Each of the second, loop windings is disposed serially on a closed loop.