Fuel Cell Vehicle Serial Parallel Switching Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fuel cell vehicles face inefficiencies in power management due to the inability to dynamically adjust the connection mode of fuel cells and power storage devices in response to varying motor loads, leading to suboptimal energy utilization and potential degradation of drivability.
Innovation Solution
A fuel cell vehicle system that includes a serial/parallel switcher and a converter, controlled by a unit that switches between serial and parallel modes based on motor load thresholds, allowing the fuel cell and power storage device to be connected in series or parallel, and the converter to be turned on or off to boost voltage as needed, optimizing energy use and maintaining battery state of charge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the converter is always on to boost voltage, then power supply capability is improved, but system efficiency deteriorates due to unnecessary voltage conversion in low load states
Solution Approach 1:
The system dynamically switches between parallel mode (converter off) and serial mode (converter on) based on motor load conditions. The control unit monitors motor load and automatically changes the connection mode of the fuel cell and power storage device, making the system adaptable to varying power demands while minimizing unnecessary voltage conversion losses.
Solution Approach 2:
The system changes the electrical connection parameter (parallel or serial) of the fuel cell and power storage device based on load conditions. In parallel mode, the converter is turned off to avoid energy loss; in serial mode, the converter is turned on to provide sufficient power. This parameter switching resolves the contradiction between power supply capability and system efficiency.
2Loss of energy
If the converter is turned off in low load states, then system efficiency is improved, but power supply capability deteriorates during high load conditions
Solution Approach 1:
The system transitions from static converter operation to dynamic operation based on real-time motor load detection. The control unit switches the converter between on and off states, and changes the connection mode between parallel and serial, ensuring adequate power supply during high load while maintaining efficiency during low load.
Solution Approach 2:
The power source system is designed to perform multiple functions through two operational modes: in parallel mode, it operates in high-efficiency state with converter off; in serial mode, it provides high power output with converter on. This multi-functionality allows the system to satisfy both efficiency and power supply requirements under different operating conditions.
3Power
If the fuel cell and power storage device are always connected in series, then power output is increased, but device complexity increases due to continuous converter operation
Solution Approach 1:
The system employs dynamic switching between parallel and serial connection modes based on motor load requirements. The control unit monitors load conditions and automatically reconfigures the connection mode, avoiding the need for continuous converter operation and reducing overall system complexity while maintaining high power output capability when needed.
4Adaptability or versatility
If the converter operates continuously, then voltage conversion capability is maintained, but energy loss increases due to unnecessary boosting in low load states
Solution Approach 1:
The system dynamically controls the converter operation based on real-time motor load conditions. The control unit turns the converter off in parallel mode during low load states to eliminate unnecessary energy loss, and turns it on in serial mode during high load states when voltage conversion capability is actually needed. This dynamic control maintains adaptability while minimizing energy waste.
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 improves system efficiency by minimizing unnecessary voltage conversion in low load states and ensuring sufficient power during high load conditions, thereby enhancing drivability and reducing battery degradation.
Implementation Method 1
a converter to be turned off when either the serial mode or the parallel mode is selected, or to be caused to boost a fuel cell voltage when the serial mode is selected and to apply the boosted voltage to the motor load
Data Source
AI summary
A switch is to switch a connection mode between a serial mode and a parallel mode. In the serial mode, a fuel cell and a power storage device are connected in series and connected to a travelling apparatus in parallel. In the parallel mode, the fuel cell is connected to the travelling apparatus in parallel. A converter is to be turned on to boost a voltage generated by the fuel cell to be applied to the travelling apparatus and to be turned off when the parallel mode is selected. A controller is to control the switch to switch a connection mode to the parallel mode when power to be consumed by the travelling apparatus is lower than a first power threshold, and to switch the connection mode to the serial mode when the power to be consumed by the travelling apparatus is higher than the first power threshold.