DC/DC Converter Control Device for Sensor Failure Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional DC/DC converters face malfunctions and failures when high-voltage-side voltage sensors fail, leading to unsafe operation and voltage imbalances, causing circuit breakdowns or insufficient motor control voltage.
Innovation Solution
The DC/DC converter control device employs two high-voltage-side voltage sensors and a failure detection mechanism, allowing continuous operation by using low-voltage-side and high-voltage-side detection voltages to monitor and switch semiconductor devices, preventing malfunctions even if one sensor fails.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single high-voltage-side voltage sensor is used for monitoring, then the device complexity is reduced, but the reliability deteriorates when the sensor fails
Solution Approach 1:
The patent implements preliminary failure detection by continuously monitoring the relationship between high-voltage-side and low-voltage-side voltages. When a sensor failure is detected before it causes system malfunction, the control device switches to a safe operation mode, preventing catastrophic failures. This proactive approach maintains reliability without requiring redundant sensors.
Solution Approach 2:
The system uses its existing voltage measurement capabilities to self-diagnose sensor failures. By comparing the detected high-voltage-side voltage with the low-voltage-side voltage through the known conversion ratio, the system can detect sensor anomalies using its own operational data, eliminating the need for additional monitoring sensors.
2Reliability
If the second switching device is fixed in turn-on state when sensor failure occurs, then the circuit is protected from breakdown, but the productivity deteriorates due to loss of voltage transformation capability
Solution Approach 1:
The patent implements dynamic control of the second switching device based on real-time sensor status. Instead of fixing the switching device in a static state, the system dynamically adjusts its operation mode: normal mode when sensors are functional, and safe operation mode when sensor failure is detected. This dynamic approach maintains circuit safety while preserving voltage transformation capability when possible.
Solution Approach 2:
The system changes operational parameters (switching device states) based on detected sensor conditions. When sensor failure is detected, the control device changes the parameter of the second switching device from dynamic control to fixed turn-on state, adapting the system's behavior to the degraded sensor condition while maintaining safe operation.
3Reliability
If voltage sensor failure is not detected, then the ease of operation is maintained, but the reliability deteriorates due to undetected malfunctions
Solution Approach 1:
The patent implements feedback-based failure detection by continuously comparing the detected voltage values against expected relationships. The control device monitors whether the high-voltage-side voltage detection value divided by the low-voltage-side voltage detection value matches the expected conversion ratio, providing continuous feedback on sensor health without requiring complex diagnostic systems.
Data Source
AI summary
With respect to a failure in voltage sensors each for detecting a high-voltage-side voltage in a DC/DC converter, it is so arranged that a circuit failure of the DC/DC converter is prevented, and that the DC/DC converter is continuingly controlled. Two voltage sensors are included therein each for detecting a high-voltage-side voltage, so that, even when a first voltage sensor for detecting a high-voltage-side voltage on one side fails to work properly, a control device turns on a second switching device, and detects a voltage by a second voltage sensor for detecting the high-voltage-side voltage on the other side, whereby a failure of the voltage sensor for detecting the high-voltage-side voltage is detected.