Regenerative Braking Control via Kinematic Loss Evaluation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for supporting drivers in braking motor vehicles, particularly electric and hybrid vehicles, often result in inefficient energy recovery due to kinematic losses in the drive train, leading to wasted mechanical energy and ineffective electrical braking.
Innovation Solution
A method that evaluates kinematic and electrical losses to optimize the actuation of both electric and mechanical brakes, recommending their use alone or in combination to maximize energy recovery, by coupling the electric machine with the drive train and considering various state variables and environmental factors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If regenerative braking is activated without proper evaluation, then electrical braking power can be increased, but mechanical energy is wasted due to kinematic losses in the drivetrain
Solution Approach 1:
The control unit continuously monitors vehicle state parameters (speed, acceleration, battery charge level, drivetrain load) and energy flow (kinetic energy, electrical power generation, drivetrain losses) to provide real-time feedback on the effectiveness of regenerative braking. This feedback loop allows the system to adjust or deactivate regenerative braking when it becomes counterproductive, preventing mechanical energy waste while maintaining optimal electrical braking power
Solution Approach 2:
The system transitions from static regenerative braking activation to dynamic control where the coupling state of the electric motor, the distribution between regenerative and mechanical braking, and the charge acceptance rate are continuously adjusted based on real-time vehicle conditions. This dynamic approach ensures electrical braking power is optimized without causing net energy loss
2Use of energy by moving object
If the electric motor operates as a generator during braking, then kinetic energy is converted to electrical energy, but thermal energy losses occur in the drivetrain
Solution Approach 1:
The system changes the operational parameters of the electric motor (torque, speed, coupling state) and the braking system (force distribution, duration) to optimize the conversion of kinetic energy to electrical energy while minimizing thermal losses in the drivetrain. By adjusting these parameters based on real-time conditions, the system maximizes useful energy recovery and minimizes wasteful thermal conversion
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 ensures effective charging of the electrical storage device by identifying optimal braking strategies that minimize mechanical losses and maximize electrical recuperation, even when kinematic losses are high, thereby enhancing the vehicle's braking performance and energy efficiency.
Implementation Method 1
the electric motor (the electric machine) as a generator. The braking effect is achieved by harnessing this mechanical kinetic energy.
Implementation Method 2
Mechanical brakes utilize frictional resistance. Through the effect of friction, the mechanical kinetic energy is converted into heat energy, thus producing the braking effect.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Method for assisting a driver in the operation, in particular in braking, of a motor vehicle (100) with an electric motor (10) for charging an electrical storage device (11), wherein the electric motor (10) can be coupled to a drive train (20) of the motor vehicle (100) in order to charge the electrical storage device (11), comprising the following steps: - evaluating the effective charging of an electrical storage device (11) by the electric motor when braking the motor vehicle (100), - providing information to the driver for the optimal actuation of a brake, in particular a mechanical and electric brake, depending on the evaluation, wherein the evaluation takes into account energy losses, in particular kinematic losses, which arise from coupling the electric motor (10) to the drive train (20), in particular from dragging along at least one component (21, 22) of the drive train (20).