Phase-Shifted Full-Bridge Converter MPPT for Varying Input Current
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photovoltaic power generation systems face instability and inefficiency in maximum power point tracking due to the constant cycling of switch transistors in DCDC converters, which fail to adapt to rapid variations in sunlight, leading to prolonged stabilization times.
Innovation Solution
A phase-shifted full-bridge converter and control method that dynamically adjusts the operation mode of switch transistors based on current input, using a correspondence between input currents and operation modes to determine phase angles and switching frequencies for optimal power tracking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If constant cycle control is used for switch transistors, then control simplicity is maintained, but adaptability to varying current deteriorates
Solution Approach 1:
The patent implements dynamic control by dividing the switching cycle into multiple variable sub-cycles. The duty cycle of each sub-cycle is adjusted according to the instantaneous current value, allowing the system to adapt to varying current conditions while maintaining a structured control framework. This resolves the contradiction by making the control system dynamic rather than static.
Solution Approach 2:
The patent changes the duty cycle parameter of switch transistors based on the detected current value. By dynamically adjusting this key parameter, the system can adapt to different operating conditions without changing the overall control structure, thus maintaining simplicity while improving adaptability.
2Stability of the object's composition
If constant switching cycle is used, then system stability is maintained, but response speed to current variations deteriorates
Solution Approach 1:
The patent segments the constant switching cycle into multiple variable sub-cycles. Each sub-cycle can be independently adjusted in duration and duty cycle based on current conditions. This segmentation allows the system to maintain the overall stable framework of fixed switching frequency while enabling rapid adjustments within sub-cycles, thus improving response speed without sacrificing stability.
3Productivity
If maximum power point tracking is implemented, then power extraction efficiency is improved, but system complexity increases
Solution Approach 1:
The patent implements maximum power point tracking through feedback control. The controller continuously monitors the current value and adjusts the duty cycle of switch transistors accordingly to maintain optimal operating conditions. This feedback mechanism enables efficient power extraction while keeping the control logic relatively simple by using direct current-based adjustment rather than complex algorithms.
Data Source
AI summary
A phase-shifted full-bridge converter, and a method and a device for controlling the phase-shifted full-bridge converter are provided. The method includes: acquiring a current currently inputted to the phase-shifted full-bridge converter; determining, based on a correspondence between inputted currents and operation modes, an operation mode corresponding to the current currently inputted to the phase-shifted full-bridge converter; and acquiring, from maximum power point tracking in the determined operation mode, a phase angle for the phase-shifted full-bridge converter and a switching frequency of a switch transistor in the phase-shifted full-bridge converter, to control the switch transistor to operate based on the phase angle and the switching frequency.