Redundant EPB Motor Drive for H-Bridge Failure Tolerance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The electronic parking brake system is vulnerable to failure if one of the transistors in the H-bridge circuit fails, leading to a complete system malfunction.
Innovation Solution
A motor driving redundancy device is implemented, which includes two motor-driving modules with their respective driver modules, monitoring modules, and processors. This setup allows for redundant current supply to the motor, ensuring continued functionality even if one module fails.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single H-bridge circuit is used to drive the motor, then the device complexity is reduced, but the reliability deteriorates because a single transistor failure causes complete system malfunction
Solution Approach 1:
The single H-bridge circuit is divided into two separate H-bridge circuits (first and second motor-driving modules), each capable of independently driving the motor. This segmentation allows the system to tolerate failures in one module while the other continues to operate, thereby improving reliability without requiring a complete system redesign
Solution Approach 2:
The patent implements a redundant motor-driving architecture where a second motor-driving module is prepared in advance as a backup. The monitoring module continuously checks the status of transistors in both modules, and upon detecting a failure in the first module, the system automatically switches to the second module. This beforehand cushioning ensures continuous operation and prevents complete system failure
2Reliability
If redundancy is implemented with two motor-driving modules, then the reliability is improved, but the device complexity increases
Solution Approach 1:
Both the first and second motor-driving modules are designed with identical functionality, each capable of independently driving the motor. This universality allows either module to take over in case of failure, simplifying the control logic as the system always expects the same interface and behavior from whichever module is active
Solution Approach 2:
The patent creates a duplicate copy of the motor-driving functionality through the second motor-driving module, which mirrors the structure and capabilities of the first module. This copying approach simplifies the redundancy implementation as the backup module is essentially an identical replica, making the switching mechanism straightforward and the overall system easier to manage despite the increased component count
Data Source
AI summary
A motor driving redundancy device for an electronic parking brake includes a first motor-driving module configured to supply current to a motor, a first driver module configured to control the first motor-driving module, a second motor-driving module configured to drive the motor, a second driver module configured to control the second motor-driving module, a monitoring module configured to monitor a status of the first motor-driving module and the second motor-driving module, and a processor configured to, when a failure is detected in either the first motor-driving module or the second motor-driving module by the monitoring module, control at least one of the first motor-driving module or the second motor-driving module to drive the motor.