Detection Circuit for Electric Vehicle Relay Drive Fault Diagnosis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fault detection solutions for the drive circuit of relays in electric vehicles are inadequate, posing safety risks due to the aging of mechanical relays and lack of effective diagnostic methods.
Innovation Solution
An electrical control device detection circuit is developed, comprising detection modules and a control module that differentiate between normal and faulty states by analyzing electrical signals, allowing for precise fault detection and identification in the drive circuit, including the use of detection power modules, switch modules, and current-limiting submodules to determine shorted-to-ground and shorted-to-power-supply faults.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a mechanical relay is used to control high-voltage loops, then the controller can indirectly control high voltage, but the relay faces aging problems and may fail after long-time operation
Solution Approach 1:
The patent implements preliminary fault detection by adding a detection circuit that continuously monitors the relay drive circuit before actual failure occurs. The detection module checks for shorted-to-ground and shorted-to-power-supply faults in advance, allowing the system to identify and respond to potential relay failures before they compromise vehicle safety.
Solution Approach 2:
The patent introduces an intermediary detection circuit between the controller and the relay. This detection circuit includes detection modules that monitor the drive circuit's electrical characteristics, acting as a mediator to identify relay faults without directly interfering with the relay's primary switching function.
2Reliability
If no fault detection solution is implemented, then the device complexity remains low, but safety risks increase due to undetected relay failures
Solution Approach 1:
The patent segments the detection function into distinct modules: a detection power module that provides test signals, detection modules that monitor specific circuit conditions, and a control module that processes fault information. This segmentation allows the detection system to be added without completely redesigning the existing relay control architecture.
Solution Approach 2:
The detection circuit is designed with multi-functionality to monitor both shorted-to-ground and shorted-to-power-supply faults using a unified detection architecture. The detection modules can identify multiple fault types through a single integrated system, reducing the need for separate detection circuits for each fault condition.
3Ease of operation
If simple relay control is used, then the control system remains simple, but diagnostic capabilities are insufficient for identifying fault types
Solution Approach 1:
The patent implements feedback mechanisms where detection modules continuously monitor the relay drive circuit and provide fault information back to the control module. The control module receives electrical signal levels from detection modules and uses this feedback to determine fault types, enabling intelligent diagnostic capabilities through continuous monitoring and response.
Solution Approach 2:
The patent utilizes parameter changes in electrical signal levels to identify different fault conditions. By monitoring changes in voltage levels and electrical characteristics during detection, the system can distinguish between shorted-to-ground faults and shorted-to-power-supply faults based on the specific electrical parameter variations each fault produces.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Embodiments of this application relate to the technical field of electronics, and disclose an electrical control device detection circuit, a detection method, and an electric vehicle. In some embodiments of this application, the detection circuit is configured to detect a drive circuit of the electrical control device. The drive circuit includes a high-side switch unit. The detection circuit includes a first detection module and a control module. A first end of the first detection module is connected to a first end of the electrical control device. A second end of the first detection module is connected to a second end of the electrical control device. A third end of the first detection module is connected to the control module. The control module is configured to obtain a first electrical signal at the third end of the first detection module; and determine, based on the first electrical signal at the third end of the first detection module, whether a fault occurs in the drive circuit of the electrical control device. In this implementation, fault diagnosis can be performed on the drive circuit of the electrical control device.