Compound Power Converter Segmentation for PFC Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power converters with Power Factor Correction (PFC) face challenges in achieving high efficiency and simplicity, particularly for lower-power devices, due to complexities and inefficiencies in existing topologies that require multiple stages and additional components, leading to increased size, cost, and energy losses.
Innovation Solution
A compound power converter design that integrates a main switched-mode converter with a supplemental converter and energy storage element, allowing energy from the storage device to power the output and facilitate PFC, reducing the need for multiple stages and minimizing energy losses by using a single flyback stage for most energy transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a second cascaded regulator is added to improve regulation, then regulation performance is improved, but power losses double
Solution Approach 1:
The power conversion function is segmented between a main flyback converter handling the majority of power and a supplemental regulator handling only the regulation portion, reducing total losses while maintaining performance
Solution Approach 2:
The supplemental regulator operates partially, activating only when needed to provide regulation during specific conditions (lighter loads, transient events), rather than continuously processing all power
2Loss of energy
If an active bridge with high-frequency switching is used to remove diodes, then efficiency is improved, but device complexity increases
Solution Approach 1:
The patent combines the flyback converter and active bridge into a single integrated stage, allowing the flyback transformer to perform both isolation and high-frequency power conversion functions, thereby maintaining efficiency while reducing complexity
Solution Approach 2:
The flyback transformer serves multiple functions simultaneously: electrical isolation, voltage transformation, and energy storage, eliminating the need for separate high-frequency inductors and reducing overall circuit complexity
3Loss of energy
If a bridgeless inductive resonant approach is used for PFC, then diode losses are eliminated, but large inductors are required making the converter difficult to implement
Solution Approach 1:
The patent changes the operating frequency parameter to high-frequency switching, which allows the use of smaller inductors while maintaining PFC functionality and eliminating diode losses through synchronous rectification
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
The compound converter achieves high efficiency and reduced complexity, enabling PFC in lower-power devices while minimizing size and cost, with most energy passing through a single flyback stage, thereby improving power factor correction and reducing overall energy losses.
Implementation Method 1
a switched-mode power converter that passes the majority of the power and a subordinate converter that provides supplementary power, when needed. The source of supplemental energy is a second output voltage. The second voltage is held in a storage capacitor
Implementation Method 2
most energy passing through a single flyback stage
Data Source
AI summary
In certain embodiments, a compound power converter passes the majority of power from input to output through only a single stage of power conversion. At least one embodiment includes a main converter with an auxiliary output. The auxiliary output energizes an energy storage element that provides input power for a supplemental converter capable of supplying the main output. The supplemental converter improves regulation and can provide holdover power for Power Factor Correction (PFC) or Uninterruptible Power Supply (UPS) operation. In certain embodiments, the power converter has at least one multi-functional inductor that supports both main regulation and supplemental regulation in a time-multiplexed manner such that, during main regulation, input energy is transferred from the input node to the output node via the multi-functional inductor, and, during supplemental regulation, the stored energy is transferred from the at least one energy storage element to the output node via the multi-functional inductor.