Four-Wheel Drive Electric Vehicle Brake System with Motor Redundancy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional brake systems for four-wheel drive electric vehicles face challenges in ensuring reliable braking performance, particularly at high speeds or during sudden maneuvers, due to the potential failure of hydraulic brake systems, which can lead to unimaginable consequences.
Innovation Solution
A brake system for four-wheel drive electric vehicles that incorporates a battery pack, four motors, a brake actuator, wheel speed sensors, resolver sensors, and a vehicle controller to manage regenerative and reverse braking, allowing the motors to take over braking duties when the hydraulic system fails, ensuring equivalent braking torque and reducing crash risks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional hydraulic brake system is used, then the braking function is simple and reliable under normal conditions, but the system becomes unsafe and unreliable when brake failure occurs during high-speed driving or sudden maneuvers
Solution Approach 1:
The patent combines the hydraulic brake system with an electric motor-driven brake system into a unified brake system. The motor can provide braking torque independently or in conjunction with the hydraulic system, ensuring that braking functionality is maintained even when the hydraulic system fails. This merging of two different braking mechanisms resolves the contradiction by providing redundancy without completely abandoning the simplicity of the conventional system.
Solution Approach 2:
The patent implements a monitoring mechanism that detects the working status of the hydraulic brake system in advance. When a failure or abnormal condition is detected, the system automatically switches to or activates the motor-driven braking mechanism as a backup. This beforehand cushioning approach ensures that braking reliability is maintained by preparing a fallback solution before actual failure occurs, without requiring the complex system to be fully active during normal operation.
2Reliability
If the hydraulic brake system is made more complex with additional safety mechanisms, then braking reliability improves, but the device complexity increases significantly
Solution Approach 1:
The patent employs a monitoring mechanism that automatically detects the working status of the hydraulic brake system and triggers a switch to the motor-driven braking mechanism when failure is detected. This self-service approach allows the system to monitor and respond to failures autonomously without requiring complex manual intervention systems or additional safety mechanisms, thereby improving reliability while controlling complexity.
Solution Approach 2:
The control unit serves as an intermediary between the hydraulic brake system and the motor-driven brake system. It receives status information from the hydraulic system, determines whether failure has occurred, and coordinates the switching between the two braking mechanisms. This intermediary approach simplifies the overall system architecture compared to having direct, complex interconnections between multiple safety mechanisms.
3Reliability
If electric motors are used to provide backup braking, then braking reliability during failure improves, but the use of energy increases due to motor operation
Solution Approach 1:
The patent implements a monitoring mechanism that continuously assesses the hydraulic brake system's status. The motor-driven braking mechanism is activated only partially or fully when the monitoring mechanism detects a failure or abnormal condition, rather than operating continuously. This partial action approach ensures that energy is consumed only when necessary for backup braking, maintaining reliability while minimizing unnecessary energy consumption during normal hydraulic system 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
The system effectively allocates brake torque across four wheels, ensuring the vehicle can maintain braking performance even if the hydraulic brake actuator fails, thereby reducing the risk of crashes by leveraging the fast response time of electric motors.
Implementation Method 1
a motor configured to drive the wheel
Implementation Method 2
the motor to be used as a generator to perform regenerative braking on the wheel
Implementation Method 3
a brake actuator configured to frictionally brake the wheel
Data Source
Figure 1
Figure 2
AI summary
A brake system (100) and a brake method for a four-wheel drive electric vehicle and a four-wheel drive electric vehicle,in the system, according to a brake mode of the electric vehicle, a state of charge of a battery pack (4) and a vehicle speed, a first brake control unit controls a motor (6) to brake a wheel (9) through a motor controller (2) and a second brake control unit controls a brake actuator (12) to brake the wheels (9). The first brake control unit further determines whether a brake torque of the brake actuator (12) on the wheels (9) fails. If yes, the first brake control unit controls the motor (6) to brake the corresponding wheel (9) through the motor controller (2).