EV Charging Inlet Terminal Temperature Correction for Overheat Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for monitoring the temperature of electric vehicle charging inlet terminals fail to account for thermal sensor transient response and offset, leading to potential thermal runaway events due to differences between measured and actual terminal temperatures, especially in faulty charge couplers or high resistance connections.
Innovation Solution
A method using an electronic controller to calculate the inlet terminal temperature by applying a temperature sensor normalization factor and a terminal normalization factor, derived from experimental measurements, to accurately regulate electrical power and prevent overheating, employing a formula such as Tterminal(t)=Tsensor(t0)+(Tsensor(t)-Tsensor(t0))*NFsensor(t))*NFterminal(t) to ensure the temperature remains below a predetermined threshold.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If thermal sensors are used to monitor inlet terminal temperature with fixed threshold, then temperature monitoring is simple and cost-effective, but measurement precision deteriorates due to transient response and offset delays
Solution Approach 1:
The system performs preliminary calibration to determine normalization factors before actual temperature monitoring. The controller stores these factors and applies them during charging to compensate for sensor transient response and offset, improving measurement precision without increasing hardware complexity
Solution Approach 2:
The patent changes the parameter approach by introducing time-varying normalization factors that account for transient thermal response. Instead of using a fixed threshold, the system dynamically adjusts temperature readings based on calibration data, resolving the contradiction between simple monitoring and precise measurement
2Device complexity
If thermal sensors directly monitor terminal temperature, then the monitoring system is simple, but reliability deteriorates due to inability to detect thermal runaway events
Solution Approach 1:
The patent introduces normalization factors as an intermediary between the thermal sensor and the temperature threshold comparison. These factors mediate the raw sensor readings to account for transient response and offset, enabling reliable thermal runaway detection while keeping the sensor hardware simple
Solution Approach 2:
The system replaces direct mechanical/physical sensor contact measurement with a computational approach. By using normalization factors derived from calibration, the system substitutes pure measurement with measurement plus correction, improving reliability without adding complex sensor hardware
3Ease of operation
If fixed temperature threshold is used for charging control, then control logic is simple, but productivity deteriorates due to premature charging shutdown
Solution Approach 1:
The patent transforms the static fixed threshold into a dynamic adaptive threshold by applying normalization factors to sensor readings. The control logic remains simple (comparing normalized temperature to threshold), but the effective threshold adapts to transient conditions, preventing premature shutdown and improving charging productivity
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 effectively prevents thermal runaway events by accurately determining the inlet terminal temperature, accounting for sensor delays and offsets, thereby ensuring safe and efficient charging operations.
Implementation Method 1
The thermal sensors are positioned in proximity to the inlet terminals that are being monitored
Implementation Method 2
regulating the application of electrical power to the inlet terminal using the electronic controller to maintain the inlet terminal temperature below a predetermined threshold
Data Source
AI summary
An electric vehicle charging system includes a temperature sensor for measuring the temperature of an inlet terminal of an electric vehicle charging inlet and an electronic controller configured to obtain an initial temperature value of the temperature sensor, obtain a current temperature value of the temperature sensor, calculate the inlet terminal temperature based on the initial temperature value, the current temperature value, a predetermined temperature sensor normalization factor, and a predetermined terminal normalization factor for the time after application of electrical power to the inlet terminal, and regulate the application of electrical power to the inlet terminal to maintain the inlet terminal temperature below a predetermined temperature threshold based on the calculated inlet terminal temperature. A method and a computer readable medium containing program instructions for determining an inlet terminal temperature of an electric vehicle charging inlet are also disclosed.