Power Combining in PoE Systems Without Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Power Over Ethernet (PoE) standards limit the power that can be supplied to a Powered Device (PD), requiring multiple Power Sourcing Equipment (PSE) channels to be synchronized, which increases complexity and restricts the types of Power Supply (PS) components that can be used.
Innovation Solution
A method where multiple isolated Power Supplies (PS) connected to separate PSE channels can combine their power without synchronization by setting input power or current limits, allowing each PS to contribute power independently based on its rating, preventing any one PS from dominating the load and ensuring compliance with IEEE standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multiple PDPS's are synchronized to supply equal power, then power distribution is balanced, but device complexity increases and adaptability decreases
Solution Approach 1:
Each PDPS unit independently monitors the total load current and automatically adjusts its own output current contribution without requiring communication or synchronization with other PDPS units. The system achieves balanced power distribution through self-regulation based on local measurements.
Solution Approach 2:
A feedback mechanism measures the total current supplied to the load and feeds this information back to control the current reference for each PDPS. This closed-loop feedback ensures that each PDPS contributes an equal share of the total load current while maintaining simple independent operation.
2Power
If multiple PSE channels are combined to increase power, then power delivery capability increases, but system complexity increases due to synchronization requirements
Solution Approach 1:
The system divides the power delivery function into independent modular PDPS units, each handling a separate PSE channel. These modular segments operate autonomously and combine their outputs without requiring complex inter-segment synchronization, simplifying the overall system architecture.
Solution Approach 2:
Multiple independent PDPS outputs are combined in parallel to supply a single load. The merging is achieved through simple parallel connection with current-sharing control, avoiding the need for complex synchronization protocols while achieving the desired power aggregation.
3Device complexity
If PDPS's operate independently without synchronization, then device complexity is reduced and adaptability increases, but power distribution balance may be compromised
Solution Approach 1:
Each independent PDPS receives feedback about the total load current and uses this information to automatically adjust its current contribution. This feedback mechanism ensures balanced power distribution while maintaining independent operation and avoiding synchronization complexity.
Solution Approach 2:
Each PDPS unit autonomously determines its current contribution based on local measurements and control logic, without requiring coordination with other units. The self-service approach maintains power balance through independent decision-making based on system-wide feedback.
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
Enables the delivery of higher power to a PD load while reducing complexity and cost by eliminating the need for synchronization between PS components and interconnections, allowing the use of non-synchronizing components and maintaining compliance with IEEE standards.
Implementation Method 1
the voltage from each PSE channel is DC-DC converted by separate isolated power supplies (the PDPS's) to the desired voltage needed by the single PD load
Implementation Method 2
If the PDPS's secondary winding output is synchronously rectified (using a synchronous switch), the PDPS outputs are connected in parallel through diodes or ideal diode rectifiers to prevent one PDPS from supplying current to other PDPS's
Data Source
AI summary
A technique for combining power to a single load from multiple power supplies using power over Ethernet (PoE) is disclosed. Each power supply is coupled to associated power sourcing equipment (PSE) providing PoE, and each PSE has a current limit. The power supplies supply approximately the same voltage, but the output voltages are typically not exactly equal. All the power supplies are connected via diodes to a common load terminal. The power supply outputting the highest voltage first supplies power to the load terminal, since only its diode is forward biased, until a PoE current limit is reached. Then its duty cycle is limited. The load terminal voltage is then inherently lowered to cause the diode of the power supply with the next highest output voltage to connect it to the load to supply additional power to the load as the first power supply continues to supply its limited current.