Motor Inverter Wire Temperature Sensing for Connection Fault Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing abnormality determination devices for motor devices with three-phase alternating current motors fail to accurately detect abnormalities in the connection portions between inverters and wires due to the difficulty in accurately calculating the sum of phase currents, especially with alternating current detection.
Innovation Solution
Employing temperature sensors at reduced influence points on the connection portions between inverters and wires to detect temperature variations, calculating temperature deviations, and correcting for ambient temperatures to determine abnormalities based on these variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the sum of phase currents is used to determine abnormalities, then the abnormality determination can be performed, but the measurement precision deteriorates because it is difficult to accurately detect instantaneous current values of alternating current
Solution Approach 1:
The patent replaces the electrical measurement system (current sensors detecting alternating current) with a thermal measurement system (temperature sensors detecting wire temperature). By measuring the temperature of the wires instead of directly measuring the alternating current, the system achieves accurate abnormality determination without the precision problems of instantaneous current detection. The temperature sensors provide stable, accurate measurements that reflect the actual current flow through the wires.
2Reliability
If temperature sensors are placed near connection portions to detect temperature variations, then the abnormality detection sensitivity is improved, but the measurement precision deteriorates due to the influence of connection portion temperature on detection values
Solution Approach 1:
The patent extracts the temperature sensor from the connection portion area and places it on the wire at a location away from the inverter connection. This separation removes the interfering thermal influence from the connection portion while preserving the sensor's ability to detect temperature variations caused by abnormal current flow. The sensor remains sensitive to wire temperature changes but is no longer contaminated by the heat from the connection interface.
Solution Approach 2:
The wire itself acts as an intermediary between the connection portion and the temperature sensor. The sensor measures the temperature of the wire, which serves as a mediator that transmits thermal information from the connection portion without being directly exposed to the high-temperature connection interface. This indirect measurement approach preserves accuracy while maintaining sensitivity to connection abnormalities.
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
Accurately determines abnormalities in the connection portions by reducing the influence of ambient temperatures and enhancing the precision of abnormality detection.
Implementation Method 1
a plurality of temperature sensors provided for each of the wires, the temperature sensors each being configured to detect a temperature
Data Source
AI summary
A multi-phase alternating current motor, an inverter for driving a multi-phase alternating current motor, a plurality of wires connecting the coil and the inverter of each phase of the motor, an abnormality determination device for determining an abnormality of the connection between the inverter and the plurality of wires, provided for each wire, a plurality of temperature sensors for detecting the temperature at a position where the influence of the temperature of the connection portion of the wiring to the inverter is reduced, the abnormality of the motor device based on the variation in temperature detected by the plurality of temperature sensors.