Switched-Mode Power Supply Feedback Capacitor Adaptation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Switched-mode power supplies face malfunctions due to inaccurate voltage feedback caused by fixed capacitors, leading to shutdowns when load changes rapidly or noise is introduced, as the capacitor's response time does not adapt to varying load sizes.
Innovation Solution
Incorporating a switching unit with multiple capacitors connected in parallel, where a first capacitor is always connected and a second capacitor is selectively connected based on load size, allowing the switching unit to control the feedback signal to the switching controller, ensuring stable operation by varying the response time according to load conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a fixed-value capacitor is connected to the feedback terminal, then the circuit structure is simple, but the response time cannot adapt to varying load sizes causing voltage feedback inaccuracy
Solution Approach 1:
The patent applies the dynamics principle by making the capacitor value dynamically adjustable based on load conditions. A switching unit selectively connects different capacitors (first capacitor for high load, second capacitor for low load) to the feedback terminal, allowing the circuit to adapt its response characteristics to varying load sizes, thereby resolving the contradiction between fixed structure and adaptive performance
Solution Approach 2:
The patent changes the capacitance parameter based on load conditions. When load size exceeds a reference value, the first capacitor is connected; when load size is below the reference value, the second capacitor is connected. This parameter change allows the feedback circuit to maintain accuracy across different operating conditions while managing complexity through controlled variability
2Speed
If a small capacitor is used, then the response time is fast, but the voltage feedback becomes inaccurate under high load conditions causing malfunctions
Solution Approach 1:
The switching unit dynamically selects between two capacitors based on load size. For high loads, the first capacitor provides appropriate filtering; for low loads, the second capacitor ensures accurate voltage feedback. This dynamic selection resolves the contradiction by matching capacitor characteristics to operational requirements rather than using a fixed value
Solution Approach 2:
The patent segments the capacitor function into two distinct capacitors, each optimized for specific load conditions. The first capacitor handles high-load scenarios, while the second capacitor handles low-load scenarios. This segmentation allows each capacitor to be optimized for its specific operating range, resolving the trade-off between response time and accuracy
3Stability of the object's composition
If a large capacitor is used, then the voltage feedback is stable, but the response time becomes slow causing shutdowns during rapid load changes
Solution Approach 1:
The system dynamically adjusts capacitance based on load size. During rapid load changes (high load condition), the first capacitor is selected to provide appropriate stability without excessive delay. During steady low-load operation, the second capacitor provides stable feedback. This dynamic adjustment resolves the contradiction between stability and response speed
Solution Approach 2:
The capacitance parameter is changed based on load conditions to optimize both stability and response time. The switching unit monitors load size and selects the appropriate capacitor, ensuring that the feedback circuit has the right time constant for each operating condition, thereby resolving the stability-speed trade-off
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 stabilizes the power supply operation by providing a fast response for low loads and a slow response for high loads, reducing fluctuations and preventing malfunctions, thus ensuring reliable power delivery.
Implementation Method 1
a light emitting unit to emit light indicative of the voltage of the output power when the voltage of the output power is equal to or greater than a predetermined threshold voltage
Implementation Method 2
a light receiving unit to receive the light emitted from the light emitting unit and output a signal indicative of the voltage of the output power
Data Source
AI summary
A switched-mode power supply includes a converter to convert input power into output power having a predetermined voltage level by performing a switching operation; a switching controller to control the switching operation of the converter based on an indication of a voltage of the output power; and an output power voltage indicating unit to provide the indication of the voltage of the output power to the switching controller according to a characteristic of the output power voltage indicating unit that varies according to the size of a load receiving the output power converted by the converter.