Motor Position Sensor Dual Supply Selection Circuit
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Solution Overview
Problem
In safety-critical BLDC motor applications, existing technologies fail to ensure reliable operation of motor position sensor devices during disruptions in supply voltage, which can lead to improper functioning of the electric motor.
Innovation Solution
The implementation of a motor position sensor device with dual supply terminals and a selection circuit that switches between a primary and secondary supply voltage, with the secondary voltage serving as a backup, generated from the electric motor's supply lines using a coupling device that inductively, capacitively, or galvanically couples alternating current voltages, ensuring continuous operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single supply voltage is used for the motor position sensor device, then the device complexity is reduced, but the reliability deteriorates during supply voltage disruptions
Solution Approach 1:
The patent applies preliminary action by generating the second supply voltage from the AC supply lines before any disruption occurs. The voltage generation circuit continuously converts AC voltage to a DC backup supply, ensuring immediate availability when the primary supply fails, rather than waiting for a disruption to occur.
Solution Approach 2:
The patent uses an intermediary approach by introducing a voltage generation circuit that converts AC supply line voltage into a usable DC supply voltage for the motor position sensor. This intermediary conversion process enables the system to bridge between the AC motor supply and the DC sensor requirements.
2Reliability
If dual supply terminals with selection circuit are implemented, then the reliability during disruptions is improved, but the device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the supply voltage system into two independent terminals: a first supply terminal for normal operation and a second supply terminal for backup operation. The selection circuit selectively connects one terminal to the motor position detection unit based on supply voltage status, allowing the system to maintain simplicity in the sensor device while achieving redundancy.
3Duration of action of moving object
If backup power supply is provided, then the duration of operation during disruptions is extended, but the loss of energy increases
Solution Approach 1:
The patent implements self-service by using the motor's own AC supply lines to generate the backup DC supply voltage through the voltage generation circuit. This eliminates the need for external backup power sources or energy storage devices, as the system serves itself by converting its existing AC supply into a redundant DC supply for the motor position sensor.
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
This solution ensures the motor position sensor device can detect the rotor position reliably even during disruptions, maintaining the electric motor's proper function by providing a backup power supply, thus preventing interruptions in rotational movement.
Implementation Method 1
a coupling device that inductively, capacitively, or galvanically couples alternating current voltages
Implementation Method 2
a coupling device that inductively, capacitively, or galvanically couples alternating current voltages
Data Source
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AI summary
A motor position sensor device (1000) comprises a motor position detection unit (1010) being configured to detect a position of a rotor (1110) of an electric motor (1100). The motor positon sensor device (1000) comprises a selection circuit (1020) being configured to couple a first supply terminal (V1000a) to provide a supply voltage (VDD) to the motor position detection unit (1010), if a level of the supply voltage (VDD) is above the threshold level, and to couple a second supply terminal (V1000b) to provide an auxiliary supply voltage (VDDN) to the motor position detection unit (1010), if the level of the supply voltage (VDD) is below the threshold level and the level of the auxiliary supply voltage (VDDN) is above the threshold level.