Sensorless Motor Commutation Using Induced Current Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional motor controllers rely on Hall effect sensors to determine the current position of a rotor, which increases manufacturing costs due to the high cost and time required for sensor production.
Innovation Solution
A motor control detector and method that uses a controller, switch circuit, and current measurement circuit to drive a stator coil and generate an induced current, allowing for phase commutation control of the stator coil without the need for a Hall effect sensor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a Hall effect sensor is used to determine the current position of the rotor, then the motor control accuracy is improved, but the manufacturing cost and time cost increase significantly
Solution Approach 1:
The patent extracts the position detection function from the Hall effect sensor and implements it through software algorithms using alternative signals (back-EMF, current, or voltage signals) already present in the motor control system. This eliminates the need for the expensive Hall effect sensor while maintaining position detection capability through signal processing and computational methods.
Solution Approach 2:
The patent replaces the mechanical/electrical Hall effect sensor system with a software-based detection system that uses mathematical algorithms to calculate rotor position from electrical signals. This substitution eliminates the physical sensor component and its associated manufacturing costs while achieving the same functional objective through computational processing.
2Reliability
If a Hall effect sensor is used for rotor position detection, then the control reliability is improved, but the device complexity increases
Solution Approach 1:
The patent merges the position detection function with the existing motor control circuitry by using the same signals (back-EMF, current, or voltage) that are already being processed for motor control. This integration eliminates the need for separate sensor circuits and reduces overall system complexity while maintaining control reliability through unified signal processing.
Solution Approach 2:
The patent makes the existing motor control signals serve multiple functions: they are used both for motor control and for rotor position detection. This multi-functionality approach eliminates the need for dedicated sensor systems, reducing device complexity while maintaining the reliability needed for both control and detection functions.
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 reduces the structural manufacturing cost of motors by eliminating the need for Hall effect sensors and effectively controls the rotor through induced current monitoring.
Implementation Method 1
transmit a current of a power supply to the stator coil so as to generate an induced current according to a change of a magnetic field of the stator coil
Data Source
AI summary
A motor control detector is configured to drive a stator coil of a motor. Stator coil includes a first terminal and a second terminal. Motor control detector includes a controller, a switch circuit, and a current measurement circuit. Controller is configured to generate a plurality of driving signals. Switch circuit is coupled to controller, first terminal and second terminal of stator coil, and is configured to be conducted according to drive signals to transmit a current of a power supply to stator coil so as to generate an induced current according to a change of a magnetic field of stator coil. Current measurement circuit is coupled to control circuit and switch circuit, and is configured to receive induced current. Controller is configured to adjust driving signals according to induced current so as to control switch circuit according to driving signals to form circuit loops to drive stator coil.