Fuel Cell Power Control to Prevent Battery Overvoltage Windup
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fuel cell electric vehicle (FCEV) control systems experience windup due to saturation, leading to overcharging and potential damage to the high voltage battery system, as well as torque fluctuations.
Innovation Solution
Implementing an overvoltage management system with a power sensor to measure and adjust the integrator of the feedback controller, setting the gain to zero or recalculating the integral term to prevent windup and overvoltage malfunctions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the integral action of a feedback controller continuously accumulates error during fuel cell saturation, then the controller attempts to compensate for the power deficit, but this causes windup resulting in overcharging and potential damage to the high voltage battery system
Solution Approach 1:
The patent implements a feedback mechanism that continuously monitors the actual power output of the fuel cell system and compares it with the commanded power. When saturation is detected (actual power differs from commanded power), the system adjusts the integral term accumulation rate based on this feedback, preventing unnecessary windup while maintaining reliable battery protection.
Solution Approach 2:
The patent dynamically adjusts the integral term calculation based on real-time operating conditions. The integrator's accumulation rate is modulated according to the difference between commanded and actual power, allowing the system to adapt its control behavior to prevent windup during saturation while maintaining effectiveness during normal operation.
2Productivity
If the feedback controller uses integral action to compensate for fuel cell power saturation, then the controller aims to maintain power balance, but this continuous accumulation causes large power commands that lead to overvoltage malfunctions
Solution Approach 1:
The patent applies partial integral action by accumulating error only when necessary (during saturation conditions). The integrator updates the integral term at a reduced rate or pauses accumulation when the fuel cell is saturated, applying just enough corrective action to maintain power balance without excessive accumulation that would cause overvoltage malfunctions.
3Power
If the integrator continuously accumulates error during fuel cell saturation, then the feedback controller generates larger corrective signals, but this results in torque fluctuations in the electric traction motors
Solution Approach 1:
The patent dynamically modulates the integrator's behavior based on saturation detection. By adjusting the integral term update rate according to real-time power balance conditions, the system generates smooth corrective signals that maintain necessary power compensation without causing abrupt torque fluctuations in the traction motors.
Data Source
AI summary
An overvoltage management system for a fuel cell electric vehicle (FCEV) includes a power sensor configured to measure a power output by a fuel cell system of the FCEV, wherein the fuel cell system is configured to generate electric current for recharging a high voltage battery system of the FCEV and a control system to determine a power command for the fuel cell system, receive the measured power output by the fuel cell system, calculate a difference between the measured power output and the power command, and based on the calculated difference, control an integrator of a feedback controller for the fuel cell system to prevent windup of the feedback controller and an overvoltage malfunction of the high voltage battery system.