BLDC Motor Torque-Current Adaptation for Washing Drum Reversing Cycles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing control methods for BLDC motors in laundry care appliances consume excessive energy and subject the motor to unnecessary strain due to the use of maximum torque-forming currents during startup, even when lower load torques are present.
Innovation Solution
A control device that detects the maximum torque-forming current during a first reversing cycle and sets a reference value for the second reversing cycle, allowing for efficient determination and adjustment of the torque-forming current to optimize energy consumption and motor strain, with options to add an offset value or use predefined minimum and maximum values to ensure robust startup.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If maximum torque-forming current is used during control phase to ensure motor startup, then motor startup reliability is improved, but energy consumption increases and motor strain increases
Solution Approach 1:
The patent applies dynamics by making the torque-forming current adaptive rather than static. The control device dynamically adjusts the torque-forming current based on actual motor conditions and startup progress, transitioning from a fixed maximum current approach to a variable current approach that matches actual load requirements, thereby reducing energy consumption while maintaining startup reliability.
Solution Approach 2:
The patent implements feedback by using position and speed sensors to continuously monitor motor state during the control phase. This feedback information is used to adjust the torque-forming current in real-time, allowing the system to reduce current when actual load is lower than maximum expected load, thus reducing energy consumption while ensuring reliable startup.
2Reliability
If maximum torque-forming current is used during control phase to ensure motor startup, then motor startup reliability is improved, but motor service life decreases due to increased strain
Solution Approach 1:
The patent reduces motor strain by dynamically adjusting the torque-forming current to match actual load conditions. By avoiding the application of maximum current when it is not needed, the motor experiences reduced mechanical and thermal stress during startup, which extends motor service life while maintaining startup reliability through sensor-based feedback control.
Solution Approach 2:
The feedback mechanism allows the control device to monitor actual motor performance and adjust current accordingly. This prevents excessive current application that would cause unnecessary motor strain, thereby extending motor service life while ensuring reliable startup through continuous monitoring and adaptive control.
3Use of energy by moving object
If average torque-forming current from previous cycles is used as reference, then energy consumption is reduced, but adaptability to changing load conditions decreases
Solution Approach 1:
The patent enhances adaptability by making the torque-forming current reference dynamic rather than static. Instead of using a fixed reference from previous cycles, the system continuously updates the reference based on actual measured values from position and speed sensors during each startup, allowing it to adapt to changing load conditions while maintaining energy efficiency.
Solution Approach 2:
The feedback from position and speed sensors enables the system to adapt to changing load conditions by continuously monitoring actual motor performance. This feedback mechanism allows the control device to adjust the torque-forming current reference in real-time, maintaining both energy efficiency and adaptability to varying operational requirements.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A control device (100) for operating a drive motor (120), in particular a BLDC drive motor, based on a torque-generating current Iq, to rotate a rotatably mounted washing drum of a laundry care appliance according to a laundry care program running during operation, wherein the laundry care program comprises at least a first reversing cycle and a second reversing cycle, each comprising a control phase (OL) and a regulation phase (CL) of the rotation of the washing drum. The control device (100) is configured to detect a maximum value of the torque-generating current Iq during the regulation phase (CL) of the first reversing cycle and to set a reference value for the torque-generating current Iq during the control phase (OL) of the second reversing cycle, which is based on the detected maximum value.