Solar Power System with Partial Current Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional photovoltaic (PV) systems face inefficiencies due to the inability to operate individual PV panels at their maximum power point (MPP), leading to reduced power production, especially under shading or environmental compromises, as all generated power must be processed through multiple DC-DC and DC-AC converters, resulting in excessive power losses.
Innovation Solution
A solar power system with n series-connected solar power units and n−1 DC-DC converting units, where a controlling unit monitors and equalizes currents, allowing each unit to operate at a target current, and operates DC-DC converting units as current bypass units if any unit generates less than a predetermined threshold, minimizing power processing and losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If conventional PV systems use a single large inverter to process power from the entire PV series string, then system complexity is reduced, but power production is reduced when panels are shaded or environmentally compromised
Solution Approach 1:
The patent segments the PV system into multiple independent power processing units, each handling a subset of PV panels. This allows individual units to operate independently, so that shading or environmental issues affecting one unit do not impact the entire system's power production, while maintaining manageable system complexity through modular architecture.
Solution Approach 2:
The patent implements local power processing units that can independently optimize power extraction from specific groups of PV panels based on their local conditions. Each unit adjusts its operation according to the environmental conditions of its associated panels, enabling local adaptation to shading or environmental compromises without affecting the entire system.
2Productivity
If DC-DC converters are used to provide local power processing on a per PV panel basis, then power production is improved by operating panels at MPP, but efficiency is sacrificed due to double power processing
Solution Approach 1:
The patent extracts the DC-DC conversion function from being applied to all power and applies it only to the differential current portion. By taking out only the necessary power processing (the difference between panel current and string current) rather than processing all power, the system achieves MPP tracking while minimizing energy losses from conversion.
Solution Approach 2:
The patent applies partial power processing by using DC-DC converters only for the portion of power that requires current equalization. Instead of processing 100% of the power through multiple conversion stages, only the necessary differential portion is converted, reducing energy losses while still enabling MPP operation.
3Productivity
If all generated power is processed through multiple DC-DC and DC-AC converters, then local power optimization is achieved, but excessive power losses occur
Solution Approach 1:
The patent extracts only the differential current portion for DC-DC conversion rather than processing all generated power. The bulk current flows directly to the inverter with minimal processing, while only the difference current undergoes DC-DC conversion. This selective extraction approach achieves power optimization while minimizing conversion losses.
Solution Approach 2:
The patent merges the bulk current path (which requires minimal processing) with the differential current path (which requires DC-DC conversion). By combining these paths at the inverter input, the system achieves both local power optimization through selective conversion and reduced overall power losses by minimizing the portion of power subjected to conversion.
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 maximizes overall power output by ensuring each PV panel operates at or near its MPP, reducing power losses by processing power only once through DC-AC inverters and minimizing the need for large, costly DC-DC converting units, thereby enhancing efficiency and reducing costs.
Implementation Method 1
A photovoltaic (PV) array is a linked collection of solar panels
Implementation Method 2
each of the n−1 DC-DC converting units is configured to control the correspondingly connected solar power units to operate at a target current generation
Data Source
AI summary
A solar power system is provided for maximizing solar power conversion. The solar power system includes n power units connected in series and n−1 DC-DC converting units, and each of the n−1 DC-DC converting units is coupled to at least one of n solar power units. Each of the n−1 DC-DC converting units is configured to control the correspondingly connected solar power units to operate at a target current generation. The solar power system further includes a controlling unit coupled to the n−1 DC-DC converting units. The controlling unit monitors and compares the n currents generated by the n solar power units. Based on the current comparison, the controlling unit determines a series current and controls the n solar power units so that each of the generated photovoltaic currents is substantially equal to the determined series current.