PMSM Control Device Sensor Failure Transition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Permanent magnet synchronous machines (PMSMs) face challenges in sensorless control due to the lack of direct measurement of rotor position and speed, leading to inefficiencies in vector control and potential system failures, particularly in critical applications like aircraft on-board systems.
Innovation Solution
A control device that includes a sensor for measuring the rotor position, estimation means for determining the rotor position in a Park estimation frame, a failure detector, and a switch to transition from sensor-based to sensorless control in case of sensor failure, ensuring continuous operation and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If sensorless control is used to eliminate the position sensor, then device complexity is reduced, but measurement precision and control accuracy deteriorate due to lack of direct rotor position measurement
Solution Approach 1:
The patent introduces an intermediary estimation mechanism that uses measurable electrical quantities (voltages and currents) as mediators to indirectly determine the rotor position. The observer estimates the rotor position by processing these electrical measurements through mathematical models, serving as a bridge between measurable electrical parameters and the unmeasurable mechanical position parameter.
Solution Approach 2:
The patent replaces the mechanical position sensor system with an electrical estimation system. Instead of using a physical sensor to directly measure rotor position, the system substitutes this with mathematical observers that estimate position based on electrical measurements and machine models, eliminating the need for mechanical sensing components.
2Measurement precision
If a position sensor is used to achieve accurate rotor position measurement, then measurement precision is improved, but reliability deteriorates due to potential sensor failures in critical applications
Solution Approach 1:
The system uses its own electrical measurements (voltages and currents) and internal mathematical models to self-determine the rotor position without external sensors. The estimation observer processes the machine's inherent electrical signals to generate position information, making the system self-sufficient and eliminating dependency on external sensing components that could fail.
Solution Approach 2:
The patent extracts and removes the position sensor component from the control system entirely. By eliminating this potentially failure-prone element and replacing it with a software-based estimation approach, the system removes the single point of failure while maintaining the necessary measurement functionality through alternative means.
3Reliability
If sensorless control is implemented to improve reliability by removing sensors, then reliability is improved, but control accuracy deteriorates due to estimation errors
Solution Approach 1:
The estimation observer implements continuous feedback by constantly comparing estimated position with actual electrical measurements and adjusting the position estimate accordingly. This closed-loop estimation process corrects accumulated errors and maintains accuracy over time by using real-time electrical feedback from the machine operation.
Solution Approach 2:
The system performs preliminary estimation of rotor position using mathematical models and electrical measurements before actual control actions are taken. This advance estimation allows the control system to prepare appropriate control signals based on predicted position, improving overall control precision while maintaining reliability.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a device for controlling a permanent-magnet synchronous machine "PMSM" comprising: a sensor for sampling a value ? m of the rotor position, monitoring means for monitoring an operating point of the PMSM according to the rotor position and the set parameters, estimation means for determining an estimate ?^ of the rotor position in a Park estimation reference frame d-? connected to the rotor, said estimation means (23) comprising adjustment means (61) for tracking said estimated rotor position ?^ with respect to said measured rotor position ? m , a failure detector for detecting a failure of said sensor, and a switch designed to connect the monitoring means to the sensor such that the monitoring means receive the measured rotor position ? m so long as the failure detector does not report any failure of said sensor, and otherwise to connect the monitoring means to the estimation means such that the monitoring means receive the estimated rotor position ?^ when the failure detector reports a failure of said sensor.