Multi-Phase Power Converter Current Balancing With Filtered Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power converter systems face challenges in balancing current flow among parallel power stages, leading to inefficiencies and potential over-current damage.
Innovation Solution
The implementation of a current sensing circuit that senses the output current of a power converter, filters the signal to produce low-frequency and high-frequency components, and uses these components to control the output current in multiple parallel power converters, enabling reconfigurability of output control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multiple power converters are coupled in parallel to supply high current, then the current supply capability is improved, but the current flow balancing among parallel power stages deteriorates
Solution Approach 1:
The patent implements a feedback mechanism where the output current of each power converter is sensed and fed back to the control circuitry. The control circuitry adjusts the duty cycle of each power stage based on the sensed current to achieve current balancing. This is evident in the control method described in claims 1-6 where current sensing circuits monitor output current and the control circuitry modifies switching duty cycles accordingly.
Solution Approach 2:
The patent introduces an intermediary current sensing circuit and control circuitry between the parallel power stages and the load. This intermediary layer processes current information from multiple power stages and coordinates their operation to achieve balanced current distribution, preventing direct interference between parallel stages while maintaining current balance.
2Power
If multiple power converters are coupled in parallel to supply high current, then the current supply capability is improved, but the efficiency deteriorates due to unbalanced current flow
Solution Approach 1:
The feedback mechanism continuously monitors output current and adjusts duty cycles to optimize power distribution. By maintaining balanced current flow among parallel stages, the system minimizes resistive losses and improves overall efficiency while preserving the high current supply capability that motivated the parallel configuration.
3Reliability
If current sensing and control circuitry is added to balance current flow, then the current balancing is improved, but the device complexity increases
Solution Approach 1:
The control circuitry is designed to perform multiple functions: it senses output current, processes current balance information, generates control signals for duty cycle adjustment, and provides over-current protection. This multi-functional design reduces the need for separate dedicated circuits for each function, thereby limiting the increase in device complexity while achieving improved current balancing.
Solution Approach 2:
The patent merges the current sensing, control signal generation, and protection functions into an integrated control system. By combining these functions into a unified control architecture, the patent reduces the number of discrete components and interconnections required, thereby mitigating the increase in device complexity that would result from adding current balancing capabilities.
4Reliability
If fixed current control is implemented in parallel power converters, then the current balancing is improved, but the adaptability to different power requirements deteriorates
Solution Approach 1:
The control system dynamically adjusts the duty cycle of each power stage based on real-time current sensing feedback rather than using fixed control parameters. This dynamic adaptation allows the system to maintain current balancing while responding to varying power requirements, load conditions, and operational scenarios, thereby preserving adaptability while achieving reliable current balance.
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 solution effectively balances current flow among parallel power stages, improving overall efficiency and preventing over-current damage, while also allowing for reconfigurability to meet different power requirements.
Implementation Method 1
a current sensing circuit configured to sense an output current of the power converter, convert the sensed output current to a first voltage, and output a low-frequency filtered second voltage based on the first voltage and a high-frequency filtered third voltage based on the first voltage
Data Source
AI summary
Circuits and methods for sensing output current of a power converter, controlling output current in multiple parallel power converters, and enabling reconfigurability of output control for multiple parallel power converters. One embodiment includes a current sensing circuit configured to be coupled to a power converter, the current sensing circuit configured to receive a first voltage representative of an output current of the power converter and output a low-frequency filtered second voltage based on the first voltage and a high-frequency filtered third voltage based on the first voltage. In some embodiments, the first voltage is generated by sensing an output current of the power converter and converting the sensed output current to the first voltage. Other embodiments include a plurality of power stages and corresponding current sensing circuits, wherein the outputs of the low-frequency filters of the current sensing circuits are coupled in common.