Ripple-Eliminating Power Converter With Two-Stage Voltage Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power converters using high-capacity electrolytic capacitors to eliminate ripples in DC voltage suffer from reduced reliability, high cost, and decreased power conversion efficiency, especially when dealing with unstable renewable energy sources.
Innovation Solution
A ripple-eliminating power converter design that employs two stages of voltage converters connected in a cascade form, with a small-capacity capacitor between them to absorb AC components, eliminating the need for high-capacity electrolytic capacitors and enhancing power conversion efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a high-capacity electrolytic capacitor is used to eliminate ripples, then the ripple elimination effect is improved, but the lifespan is reduced and reliability deteriorates
Solution Approach 1:
The patent introduces an intermediary circuit between the first and second voltage converters that processes the ripple-containing DC voltage. This intermediary circuit uses a ripple elimination capacitor with significantly smaller capacity than conventional electrolytic capacitors, acting as a mediator to remove AC components without requiring the large capacitance of traditional solutions, thereby improving reliability while maintaining ripple elimination effectiveness
Solution Approach 2:
The patent segments the voltage conversion process into two distinct stages: a first voltage converter that generates DC voltage with ripple components, and a second voltage converter that receives the processed voltage. By dividing the system and inserting a ripple elimination stage between them, the patent avoids the need for a single large-capacity electrolytic capacitor, thus improving lifespan and reliability while maintaining effective ripple elimination
2Object-generated harmful factors
If a high-capacity electrolytic capacitor is used to eliminate ripples, then the ripple elimination effect is improved, but the cost increases
Solution Approach 1:
The patent introduces an intermediary circuit between the first and second voltage converters that processes the ripple-containing DC voltage. This intermediary circuit uses a ripple elimination capacitor with significantly smaller capacity than conventional electrolytic capacitors, acting as a mediator to remove AC components without requiring the large capacitance of traditional solutions, thereby improving reliability while maintaining ripple elimination effectiveness
Solution Approach 2:
The patent replaces expensive, short-lifespan high-capacity electrolytic capacitors with smaller-capacity capacitors that are more cost-effective and have longer operational lives. The ripple elimination capacitor has a capacity of 200 µF or less, significantly reducing component cost while maintaining effective ripple elimination through the two-stage voltage converter architecture
3Object-generated harmful factors
If a high-capacity electrolytic capacitor is used to eliminate ripples, then the ripple elimination effect is improved, but the power conversion efficiency decreases
Solution Approach 1:
The patent introduces an intermediary circuit between the first and second voltage converters that processes the ripple-containing DC voltage. This intermediary circuit uses a ripple elimination capacitor with significantly smaller capacity than conventional electrolytic capacitors, acting as a mediator to remove AC components without requiring the large capacitance of traditional solutions, thereby improving reliability while maintaining ripple elimination effectiveness
Solution Approach 2:
The patent segments the voltage conversion process into two distinct stages: a first voltage converter that generates DC voltage with ripple components, and a second voltage converter that receives the processed voltage. By dividing the system and inserting a ripple elimination stage between them, the patent avoids the need for a single large-capacity electrolytic capacitor, thus improving reliability while maintaining effective ripple elimination
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 effectively reduces AC current ripples without high-capacity electrolytic capacitors, increasing the lifespan of the converter and improving power conversion efficiency by using a two-stage voltage converter structure with step-up/step-up or step-down/step-down configurations.
Implementation Method 1
a ripple-eliminating capacitor disposed between the first voltage converter and the second voltage converter to transfer a DC component of the first voltage to the second voltage converter by eliminating an AC component included in the first voltage
Data Source
AI summary
A ripple-eliminating power converter includes a first voltage converter configured to output a first voltage by stepping up or down a DC voltage supplied from a battery cell; a second voltage converter configured to receive the first voltage outputted from the first voltage converter and output a second voltage by stepping up or down the first voltage; and a ripple-eliminating capacitor disposed between the first voltage converter and the second voltage converter to transfer a DC component of the first voltage to the second voltage converter by eliminating an AC component included in the first voltage.