PoDL Circuit Breakers for Wire Fault Protection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Power over Data Lines (PoDL) systems in automobiles face issues with temporary shorts to ground or battery voltage, which can disrupt Ethernet communications and potentially damage components without adequate protection.

Innovation Solution

The implementation of high-side and low-side circuit breakers in the Power Sourcing Equipment (PSE) that automatically uncouple the voltage source from the wire pair during faults and perform a retry operation once the fault is removed, using controllers to monitor voltage levels and manage the breakers to prevent damage and resume normal operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If PoDL transmits power over a single wire pair with differential data signals, then flexibility and ease of installation are improved, but vulnerability to wire faults (shorts to ground, battery voltage, or between wires) increases

Engineering Contradiction:

ImproveflexibilityVSAvoidvulnerability to wire faults

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The system performs preliminary fault detection by monitoring voltage levels on the wire pair before power transmission continues. When a fault condition is detected (voltage outside expected range), the circuit breakers open to isolate the fault before it can cause damage. This preliminary detection and isolation action prevents the vulnerability from escalating into component destruction.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

High-side and low-side circuit breakers are introduced as intermediary protective elements between the power source and the wire pair. These breakers act as mediators that can quickly disconnect the power transmission path when faults are detected, protecting the system from harmful electrical conditions while allowing normal power transmission to proceed when conditions are safe.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If circuit breakers are implemented to protect against faults, then system reliability and protection from damage are improved, but device complexity increases

Engineering Contradiction:

Improveprotection from damageVSAvoidcircuit breaker implementation

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The high-side and low-side circuit breakers serve multiple functions: they provide overcurrent protection, fault isolation, and automatic retry capability. By consolidating these protective functions into a single multi-functional circuit breaker assembly, the design reduces overall system complexity compared to implementing separate protection mechanisms for each function.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The circuit breakers are designed with automatic operation capability - they self-activate when fault conditions are detected through voltage monitoring, and they automatically attempt to close again after a predetermined time interval. This self-service behavior eliminates the need for complex manual intervention systems or additional control circuitry, simplifying the overall protection mechanism.

Inventive Principle:

Principle #25Self-service

3Productivity

If the system automatically retries after fault isolation, then productivity and quick resumption of operation are improved, but risk of repeated fault exposure increases

Engineering Contradiction:

Improvequick resumption of operationVSAvoidrisk of repeated fault exposure

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The circuit breakers implement periodic retry action by automatically attempting to close after a predetermined time interval following fault isolation. This periodic retry mechanism balances productivity (quick resumption when faults are temporary) with reliability (allowing sufficient time for transient faults to clear). The predetermined interval is calibrated to be short enough for quick recovery but long enough to ensure transient faults have cleared.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS10090666B2Circuit architectures for protecting against PoDL wire faults

Publication Date: 2018.10.02 ANALOG DEVICES INT UNLTD CO

AI summary

In one embodiment, a PoDL system includes a PSE that uses high side and low side circuit breakers that uncouple the PSE voltage source from the wire pair in the event that a fault is detected. Faults may include a temporary short to ground, or to a battery voltage, or between the wires. The breakers perform an automatic retry operation in the event the fault has been removed. The voltages on the wires in the wire pair may be monitored to determine whether the voltages are within a normal range or indicative of a fault condition. Other embodiments are disclosed.