Electric Motor Control Device Abnormality Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electric motor control systems require presetting permissible values for friction torque and friction force, and pre-storing vibration waveforms to detect abnormalities, which is operationally cumbersome and inefficient.
Innovation Solution
An electric motor control device with a command generation unit, operation detection unit, drive control unit, current control unit, mechanical characteristic estimation unit, integration unit, and abnormality detection unit that automatically derives mechanical characteristic permissible thresholds and detects abnormalities based on estimation values and integrated drive time or drive amount, eliminating the need for manual presetting and waveform storage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If permissible values for friction torque and friction force are preset to perform failure diagnosis, then abnormality detection capability is improved, but operational complexity increases due to required presetting operations
Solution Approach 1:
The system automatically determines permissible values by performing move and stop operations multiple times and calculating statistical parameters (mean and standard deviation) from the measured friction torque and friction force values. This self-service mechanism eliminates the need for manual presetting while maintaining reliable abnormality detection capability.
Solution Approach 2:
The system performs preliminary move and stop operations to collect data and calculate permissible values before actual failure diagnosis begins. This preliminary action establishes the baseline criteria automatically, so that subsequent abnormality detection can proceed without manual intervention.
2Measurement precision
If vibration waveform is pre-stored in database to calculate criterion for abnormality determination, then detection accuracy is improved, but operational complexity increases due to waveform storage requirements
Solution Approach 1:
The system automatically extracts feature frequencies from vibration waveforms during operation and calculates statistical criteria (mean and standard deviation) without requiring pre-stored reference waveforms. This self-service approach maintains detection accuracy while eliminating manual waveform storage operations.
Solution Approach 2:
The system extracts only the necessary feature frequency components from the vibration waveform using FFT analysis, rather than storing entire waveform datasets. This extraction approach reduces operational complexity while preserving the essential information needed for accurate abnormality detection.
3Reliability
If manual presetting of permissible values and waveform storage are required, then diagnostic criteria can be established, but time consumption increases
Solution Approach 1:
The system performs preliminary operations to automatically collect data and establish diagnostic criteria during initial operation phases. By automating the criteria establishment process through predefined move and stop sequences, the system eliminates time-consuming manual presetting while ensuring reliable diagnostic criteria are formed.
Solution Approach 2:
The system uses feedback from multiple measured operations to automatically calculate and refine permissible values and criteria. This feedback mechanism enables automatic establishment of diagnostic criteria without manual intervention, significantly reducing the time required compared to conventional manual presetting methods.
Data Source
AI summary
A motor-control device includes: a command generation unit; an operation detection unit; a drive control unit outputting a drive control signal, a speed signal, and a drive force signal; a current control unit outputting a drive current and the drive current detection value; a mechanical characteristic estimation unit outputting a mechanical characteristic estimation value; an integration unit outputting an integrated drive time or drive amount integrated value of a drive unit; a set period determination unit outputting a signal indicating a set period for a mechanical characteristic permissible threshold output unit; a mechanical characteristic permissible threshold output unit outputting a mechanical characteristic permissible threshold; and a mechanical characteristic abnormality detection unit detecting a mechanical characteristic abnormality.