Fuel Cell Converter Protection Under Battery Voltage Difference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Large vehicles equipped with fuel cells and electric batteries face challenges in stabilizing voltage differences during voltage conversion, leading to potential damage to converters due to reverse currents, which can disrupt power supply and stability during operation.
Innovation Solution
A moving object configuration with a first battery (fuel cell) and a second battery (electric battery) of higher voltage, along with a converter and a protector system, where a processor controls the voltage difference by determining the required output of the first battery based on a target voltage difference and operational requests, using a disturbance observer for power control to prevent converter damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If voltage conversion is performed from first battery to second battery through converter, then power supply to high-voltage devices is enabled, but voltage difference instability causes reverse current that damages converter
Solution Approach 1:
The control unit performs preliminary assessment of voltage differences between first and second batteries before enabling voltage conversion. When voltage difference exceeds threshold, the control unit preemptively adjusts output voltage of first battery or limits charging current to second battery, preventing reverse current damage before it occurs
Solution Approach 2:
The system continuously monitors voltage differences between first and second batteries in real-time. Based on feedback from voltage sensors, the control unit dynamically adjusts converter operation parameters, output voltage of first battery, or charging current to second battery, ensuring voltage stability and preventing converter damage
2Reliability
If converter is disabled to protect from reverse current damage, then converter reliability is improved, but power demand response capability deteriorates
Solution Approach 1:
Instead of disabling the converter, the system changes operational parameters such as output voltage of first battery, charging current to second battery, or converter duty cycle based on real-time voltage difference measurements. This maintains converter operation within safe parameters while preserving power response capability
Solution Approach 2:
The system implements dynamic control where converter operation mode changes continuously based on operating conditions. When voltage difference is within safe range, converter operates normally for rapid power response. When voltage difference exceeds threshold, control parameters are dynamically adjusted to prevent damage, enabling flexible adaptation without complete converter shutdown
3Reliability
If output voltage of first battery is increased to maintain voltage difference, then converter protection is improved, but power availability to moving object deteriorates
Solution Approach 1:
The control unit implements multi-functionality by simultaneously managing voltage stabilization and power delivery. It coordinates control of first battery output voltage, second battery charging current, and converter parameters to achieve both voltage difference stability and adequate power availability to moving object based on real-time power demand assessment
Solution Approach 2:
When voltage difference becomes unstable, the system applies partial action by adjusting only the necessary parameters (output voltage of first battery or charging current to second battery) rather than completely limiting power. This maintains voltage stability while preserving sufficient power availability for moving object operation
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 enables stable management of voltage differences and rapid response to power demands, preventing converter failure and ensuring stable operation by controlling the output of the first battery and maintaining a safe voltage difference, thus enhancing the reliability of the moving object.
Implementation Method 1
a converter electrically connected to the first battery and the second battery and configured to convert the voltage from the first battery and to provide the converted voltage to the second battery
Data Source
AI summary
A moving object capable of protecting a converter and a method therefor, includes a first battery outputting a voltage lower than a predetermined voltage and a second battery outputting a voltage higher than the predetermined voltage; a converter electrically connected to the first battery and the second battery and configured to convert the voltage from the first battery and to provide the converted voltage to the second battery; a protector configured to control the voltage of the first battery, which is provided to the converter, in response to a voltage difference between the first battery and the second battery reaching a protection condition; and a processor electrically connected to the protector and configured to determine, in response to the protection condition being reached, a required first battery output according to a target voltage difference between the first battery and the second battery and a request control of the moving object and to control an output of the first battery.