Electrical Machine Torque Calibration Using Injected Test Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for calibrating electrical machines for a specifiable torque value are complex, slow, and costly, particularly due to the need for experimental determination on a test bench, which neglects machine-specific dependencies and tolerances.
Innovation Solution
A method involving the specification of a current vector with a test signal superimposed on it to capture and evaluate a response signal, allowing for the determination of a calibrated current vector to operate the electrical machine efficiently for the desired torque value, enabling self-calibration independent of a test bench and external sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If experimental determination of MTPC locus curve is performed on a test bench using a golden sample machine, then the calibration data can be obtained, but the process becomes complex, slow, and costly
Solution Approach 1:
The electrical machine performs self-calibration by using its own control unit to generate test signals, measure response signals through integrated sensors, and automatically determine calibrated current vectors without requiring external test bench equipment or manual intervention. This eliminates the complex and costly golden sample machine approach while maintaining calibration accuracy.
Solution Approach 2:
The patent replaces the mechanical test bench setup with an electronic/self-contained calibration system. Instead of using physical test equipment to measure torque and current characteristics, the system uses electronic signal injection and measurement with mathematical evaluation to determine calibration parameters, significantly simplifying the process.
2Measurement precision
If experimental determination of MTPC locus curve is performed on a test bench, then calibration data can be obtained, but the calibration process becomes slow
Solution Approach 1:
The electrical machine performs self-calibration by using its own control unit to generate test signals, measure response signals through integrated sensors, and automatically determine calibrated current vectors without requiring external test bench equipment or manual intervention. This eliminates the complex and costly golden sample machine approach while maintaining calibration accuracy.
Solution Approach 2:
The calibration process is performed preliminarily during manufacturing or initial setup, and the calibrated data is stored for immediate use. This preliminary calibration action eliminates the need for time-consuming recalibration during operation, allowing the machine to be ready for production use immediately.
3Measurement precision
If experimental determination of MTPC locus curve is performed on a test bench, then calibration data can be obtained, but the cost increases
Solution Approach 1:
The electrical machine performs self-calibration by using its own control unit to generate test signals, measure response signals through integrated sensors, and automatically determine calibrated current vectors without requiring external test bench equipment or manual intervention. This eliminates the complex and costly golden sample machine approach while maintaining calibration accuracy.
Solution Approach 2:
The patent uses simple, inexpensive sensors already integrated into the electrical machine (such as current sensors and position sensors) for calibration measurements, replacing the need for expensive external test bench equipment. This disposable-like approach uses existing resources rather than requiring costly specialized measurement systems.
4Ease of operation
If standard field-oriented control is used without calibration, then the control can operate the electrical machine, but it cannot account for machine-specific dependencies, spreads, and changes over time
Solution Approach 1:
The calibration process provides feedback about the actual machine characteristics by measuring response signals and comparing them with expected values. This feedback is used to adjust the control parameters and store calibrated data that compensates for machine-specific variations, ensuring reliable torque generation throughout the machine's operational life.
Solution Approach 2:
The calibration process determines and stores specific parameter values (calibrated current vectors) that are tailored to the individual machine's characteristics. These parameter changes allow the control system to adapt to machine-specific dependencies, material spreads, and aging effects, maintaining reliable torque generation despite variations from ideal conditions.
Data Source
AI summary
The invention relates to a method (400) for calibrating the control of an electrical machine (120) for a specifiable torque value (T_Des), the electrical machine (120) being operated by means of field-oriented control. The method comprises the steps of: a.) specifying a current vector (Ix_V) (410) for producing the specifiable torque value (T_Des) by means of a connectable electrical machine (120), b.) specifying a test signal (Sx_Test) (420) and superimposing the test signal (Sx_Test) on the current vector (Ix_V), c.) capturing (430), by means of a sensor (130), a response signal (Sx_Antw) resulting from the superimposing, e.) determining (450) a calibrated current vector (I_Vk) according to the evaluation of the response signal (Sx_Antw).