Fuel Cell Anode Pressure Control Valve Warm-Up Strategy
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Solution Overview
Problem
Existing fuel cell systems face challenges in maintaining consistent anode gas pressure control due to temperature changes, leading to potential overshooting and damage to the fuel cell components, particularly at initial activation, and existing solutions complicate the system with additional sensors and risk overcurrent issues.
Innovation Solution
A fuel cell system configuration that includes an anode gas supply passage with an anode pressure control valve and a valve control unit, which controls the anode pressure control valve and anode gas valve to maintain a first pipe pressure below a predetermined level before stopping, and warms up the anode pressure control valve by applying a current at activation to ensure consistent gas boost speed and reduce overshooting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a normally closed solenoid valve is used for anode pressure control, then the valve can be operated with a simple duty ratio control, but the valve opening degree varies with temperature changes causing pressure overshooting at initial activation
Solution Approach 1:
The patent applies preliminary action by warming up the solenoid valve before initial operation. The control device performs a warm-up operation by supplying a drive signal to the solenoid valve before the fuel cell system starts operating, which stabilizes the plunger sliding resistance and prevents pressure overshooting when the valve is first activated.
Solution Approach 2:
The patent implements feedback by measuring the anode gas pressure and using this information to control the solenoid valve duty ratio. The control device includes a pressure sensor that detects anode gas pressure and feeds this information back to the control unit, which adjusts the valve opening to maintain stable pressure despite temperature variations.
2Reliability
If auxiliary devices such as resistance measuring devices or temperature sensors are added to measure electrical resistance or temperature, then the solenoid coil temperature can be estimated and duty ratio corrected, but the system becomes complicated and production cost increases
Solution Approach 1:
The patent applies self-service by using the fuel cell system's own operational parameters to determine solenoid valve control. Instead of adding external temperature sensors or resistance measuring devices, the control device uses the anode gas pressure feedback and operational state information already available in the system to adjust the duty ratio appropriately.
Solution Approach 2:
The patent changes the control parameter from direct temperature or resistance measurement to duty ratio adjustment based on pressure feedback. The control device modifies the duty ratio of the drive signal according to the measured anode gas pressure and operational conditions, achieving accurate control without needing to directly measure temperature or resistance.
3Reliability
If the anode pressure control valve is opened at initial activation to warm up the solenoid valve, then consistent gas boost speed is achieved, but anode gas pressure may overshoot and damage fuel cell components
Solution Approach 1:
The patent uses feedback control to prevent pressure overshooting during warm-up. The pressure sensor continuously monitors anode gas pressure and feeds this information back to the control unit, which adjusts the solenoid valve duty ratio in real-time to maintain pressure within safe limits while still achieving adequate warm-up.
Solution Approach 2:
The patent applies dynamics by making the duty ratio adjustable based on operational conditions. The control device dynamically changes the duty ratio according to the fuel cell's operational state and temperature conditions, allowing aggressive warm-up when safe and conservative operation when pressure limits are approached.
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 configuration effectively prevents damage to fuel cell components by maintaining a safe pressure and ensuring consistent anode gas boost speed, reducing the risk of overshooting and system degradation, while simplifying the system and avoiding overcurrent issues.
Implementation Method 1
the anode pressure control valve is an ON/OFF type valve internally including a solenoid coil
Implementation Method 2
a sliding resistance of a plunger as a movable iron core
Data Source
AI summary
A fuel cell system that supplies an anode gas and a cathode gas to a fuel cell to cause the fuel cell to generate an electricity. The fuel cell system includes a high pressure tank, an anode gas supply passage configured to supply the anode gas to the fuel cell from the high pressure tank, an anode pressure control valve disposed on the anode gas supply passage, the anode pressure control valve adjusting an anode gas pressure of the fuel cell, an anode gas valve disposed between the high pressure tank and the anode pressure control valve, the anode gas valve adjusting a source pressure of the anode pressure control valve, and a valve control unit configured to control to open and close the anode pressure control valve and the anode gas valve on the basis of an operating state of the fuel cell system. The valve control unit controls the anode pressure control valve and then closes the anode pressure control valve after the valve control unit closes the anode gas valve such that a first pipe pressure becomes less than a predetermined pressure before the fuel cell system is stopped, the first pipe pressure being a pressure inside a first pipe between the anode gas valve and the anode pressure control valve in the anode gas supply passage. The valve control unit opens the anode pressure control valve at an activation of the fuel cell system. The predetermined pressure is smaller than a pressure that degrades a durability of the fuel cell at the activation of the fuel cell system.