Microcontroller Circuit Breaker Thermal Memory
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional circuit breakers using RC circuits or timers for thermal modeling after a trip event lack precision and flexibility, failing to accurately account for cooling fluctuations and environmental factors, which can compromise insulation integrity and lead to delayed recognition of thermal faults.
Innovation Solution
A microcontroller-based circuit breaker that continuously models the temperature of a conductor by measuring current and using an energy storage device to maintain power during and after a trip event, allowing for precise and flexible thermal modeling of both heating and cooling phases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a microcontroller is powered by primary current to thermally model a conductor, then thermal modeling precision is improved, but the microcontroller loses power and cannot continue modeling after the circuit breaker trips
Solution Approach 1:
An energy storage device (capacitor) is introduced as an intermediary between the primary current and the microcontroller. The capacitor stores electrical energy during normal operation and releases it when the circuit breaker trips, maintaining continuous power to the microcontroller so it can uninterrupted thermal modeling of the conductor during both heating and cooling phases
Solution Approach 2:
The energy storage device is charged in advance during normal circuit operation before a trip event occurs. This preliminary energy accumulation ensures that when the circuit breaker trips and primary current stops, the microcontroller immediately has sufficient power stored to continue thermal modeling without interruption
2Duration of action of stationary object
If an RC circuit is used to hold voltage proportional to temperature, then thermal modeling is maintained after tripping, but measurement precision and flexibility are reduced
Solution Approach 1:
The patent replaces the passive RC circuit approach with an active microcontroller-based thermal modeling system. The microcontroller executes sophisticated thermal models that account for environmental factors and cooling rates, providing significantly higher measurement precision and flexibility compared to simple RC voltage decay methods
Solution Approach 2:
The thermal model implemented by the microcontroller can dynamically adjust parameters such as cooling rates, ambient temperature compensation, and conductor characteristics. This allows the system to adapt to different operating conditions and protected loads, providing flexibility that fixed RC circuits cannot achieve
3Reliability
If the circuit breaker trips and primary current stops, then thermal protection is activated, but the microcontroller cannot continue monitoring conductor cooling
Solution Approach 1:
The energy storage device serves as a mediator that bridges the gap between primary current interruption and microcontroller operation. It maintains the information flow about conductor temperature by keeping the microcontroller powered, allowing continuous monitoring of the cooling process and preservation of thermal history data
Solution Approach 2:
The system ensures continuity of useful action by maintaining uninterrupted thermal modeling through the energy storage device. The microcontroller continuously updates the thermal model during both heating and cooling phases, ensuring no gap in monitoring and preserving complete thermal history information
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 approach provides significantly more accurate thermal modeling and enhanced protection against thermal faults by maintaining uninterrupted thermal monitoring, allowing for user-modifiable models and improved recognition of residual heat, thus ensuring better insulation integrity and safety.
Implementation Method 1
the controller continues to model the temperature of the conductor uninterrupted as the conductor cools by receiving power from an energy storage device
Implementation Method 2
As current is passing through the conductor, heat is generated. The microcontroller is programmed to estimate the temperature of the conductor using a thermal model based on a measurement of the current passing through the conductor
Data Source
AI summary
A circuit breaker system for providing thermal protection to a conductor conducting current from a power source to a load. While the power source is connected to the load, a microcontroller is powered by the current passing through the conductor to thermally model the temperature of the conductor. If the microcontroller determines that the temperature of the conductor has risen to an undesirable or unsafe level, the circuit breaker disconnects the power source from the load and the current no longer passes through the conductor. With no current passing through the conductor, the microcontroller no longer receives power from the conductor. Instead, the microcontroller continues to model the temperature of the conductor as the conductor cools to an ambient temperature by receiving power from an energy storage device. Accordingly, the microcontroller continuously models the temperature of the conductor until the temperature of the conductor cools to the ambient temperature.