Drainage Pump Frequency Control for Reliable Washing Appliances
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current washing machine and dishwasher drainage pump control methods are inefficient and prone to premature failure due to fixed frequency operation, leading to increased energy consumption and maintenance challenges, as they do not optimize drainage processes based on varying water levels or flow requirements.
Innovation Solution
A control method that adjusts the frequency of the motor supply voltage for the drainage pump unit, using a stator voltage as a reference to regulate the frequency between preset values, optimizing current consumption and reducing the risk of suboptimal operation due to motor construction variations, thereby ensuring efficient and reliable drainage processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the drainage pump unit operates at a fixed determined frequency for a preset time period, then the drainage process can be completed, but the pump unit experiences premature faults and reduced reliability due to inefficient operation
Solution Approach 1:
The patent applies dynamics by transitioning from fixed frequency operation to variable frequency operation. The control means regulate the supply frequency of the synchronous motor during the drainage process, allowing the pump unit to adapt its operating characteristics dynamically. This enables the pump to operate more efficiently by adjusting speed according to actual drainage needs, reducing premature faults and extending operational lifespan.
Solution Approach 2:
The patent implements parameter changes by modifying the supply frequency parameter of the motor during operation. The control means adjust the frequency from a fixed determined frequency to variable frequencies selected from a plurality of preset frequencies. This parameter variation optimizes the drainage process efficiency and reduces stress on the pump unit, thereby improving reliability.
2Reliability
If the drainage pump unit is made bigger to overcome premature faults, then reliability may improve, but the cost increases excessively
Solution Approach 1:
Instead of increasing the physical size of the pump unit, the patent changes the operational parameters by implementing variable frequency control. The control means select from multiple preset frequencies to optimize motor operation during drainage. This approach maintains the original pump unit size while improving reliability through smarter control, avoiding excessive manufacturing costs.
Solution Approach 2:
The patent uses dynamic frequency adjustment to improve pump unit reliability without increasing its size. By allowing the motor to operate at different frequencies selected from preset values, the system optimizes performance and reduces stress on components, achieving enhanced reliability through control strategy rather than hardware scaling.
3Productivity
If the drainage pump unit operates at determined frequency for preset time, then the drainage process can be completed, but energy efficiency is suboptimal and current consumption is excessive
Solution Approach 1:
The patent optimizes energy efficiency by changing the frequency parameter during the drainage process. The control means select from a plurality of preset frequencies based on the drainage requirements at different stages. This dynamic parameter adjustment reduces motor current consumption while ensuring the drainage process is completed efficiently, avoiding both excessive energy use and incomplete drainage.
Solution Approach 2:
The patent implements periodic action by using different frequency settings at different stages of the drainage process. The control means switch between preset frequencies periodically or based on water level conditions, optimizing energy consumption during each phase of drainage while maintaining productivity.
4Device complexity
If fixed frequency operation is used, then the control system is simple, but the drainage process is inefficient and pump reliability is reduced
Solution Approach 1:
The patent introduces dynamic frequency control to improve pump reliability while maintaining reasonable control system complexity. The control means are adapted to select from preset frequencies, providing a balance between sophistication and simplicity. This dynamic approach optimizes drainage efficiency and extends pump life without requiring overly complex control architecture.
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 approach allows for more efficient and reliable drainage operations by minimizing current consumption and extending the lifespan of the drainage pump unit, while maintaining optimal performance across different motor constructions and varying drainage conditions.
Implementation Method 1
a permanent-magnet synchronous motor for rotating the impeller at a determined speed of rotation
Data Source
AI summary
Control method for a washing household appliance comprising a drainage pump unit with an impeller and a motor supplied with an alternating supply voltage of a determined frequency from among a plurality of possible preset frequencies. According to one implementation the method involves an adjustment stage in which the frequency of the motor supply voltage is regulated between the preset frequencies. The method also includes an application stage in which a stator voltage is applied to the motor, the frequency of the motor supply voltage being regulated between the preset frequencies in accordance with the stator voltage applied.