Regen Drive turns laundry green
19 December 2007
High performance torque measurement is helping to improve the energy efficiency of domestic washing machines, enabling consumers to make greener purchase decisions.
The Eco Rating stickers that provide potential buyers with a clear assessment of white goods' environmental performance now play a major role in retail sales. Manufacturers want to achieve the best classification possible, so are redesigning their machines to reduce power consumption.
Technical Solution of Stoke-on-Trent began looking at the issue and came up with several initiatives that addressed different aspects of the situation. One idea involved technology transfer from other fields of engineering. Technical Director Andrew Stephen explains: "Washing machines energy is delivered through their main drive motor and we reckoned that there may be some savings using sophisticated motor control." "Front loaders are – of course – horizontal axis, so the load, i.e. the wet laundry, is being lifted on one side of the axis and falling on the other side. We wondered if this offered possibilities for regenerative energy recovery, a technique we have used in many industrial projects." Stephen knew that considerable research would be required, so built a test rig with which he could subject washing machine system to extensive tests using an industry standard inverter to simulate the various washing cycles etc.
A critical element of the programme was the ability to make continuous accurate torque measurements, and for this he used TorqSense transducer from Sensor Technology in Bicester. The initial attraction to TorqSense was that it is easy to install and use because it does not use fiddly slip rings to contact the motor shaft, but rather a non-contact radio frequency link. "We have to glue a couple of tiny piezoelectric combs onto each test shaft, but that takes a matter of seconds.
The time saving over a big project is measurable and significant, but far more importantly is the avoidance of frustration. With slip rings test engineers can end up tearing their hair out." But more importantly, TorqSense's non-contact operation did not add an extra drag load to the results, nor affect the dynamic changes in torque as the load went over 'top dead centre'. The former is a constant error, which Stephens could have calculated out, but the latter could have made it impossible to collect the highly accurate, highly time-resolved torque data necessary for success.
By measuring the torque change he could define the exact moment when to switch the drive from power to regeneration and make the most of the potential energy released by the falling load. Given that the motor could be rotating at up to 1500rpm, this called for very accurate data collection and equally responsive control programmes.
For here he could select the best flux curve for each motor and each washing cycle tested. "Our findings were that this technique is definitely worth building into next generation washing machines, and many of the leading manufacturers will be doing this," says Stephen. "As you would expect savings varied between the different motors and cycles. With a half load of lightweight nylon items, the saving is negligible, but with a full load of heavy cottons plus a drum load of water it's a different matter, with 15 percent energy reduction. This would actually take a few quid of the average household electricity bill, and help manufacturers achieve Class 1 Eco rating." "But far more importantly multiplying it up through the whole population and the annual carbon reductions are very meaningful."
Other Press Releases By This Company
- 11/03/2019 - Sensor Technology keeps hydraulic projects on course
- 14/01/2019 - Mass market electric vehicles getting revved up for launch
- 15/11/2018 - Measuring torque without slip rings
- 16/07/2018 - Pay as you sense
- 08/06/2018 - Long service motors tested after re-engineering
- 05/04/2018 - Optical rotary torque sensors suitable for low torque and high band width measurements
- 20/02/2018 - Pump and valve innovator finds a test rig technology that talks the torque
- 20/02/2018 - Electric vehicle pioneer favours wireless test rigs
- 05/02/2018 - Pump and valve innovator finds a test rig technology that talks the torque
- 14/12/2017 - Chemical engineers talk sense about mixer efficiencies
- 14/11/2017 - Sensor Technology keeps hydraulic projects on course
- 14/09/2017 - Electric vehicle pioneer favours wireless test rigs
- 21/06/2017 - Torque test ensures reliability of steerable drills
- 10/06/2013 - Torque Sensor guarntees Tip Top-Taps!
- 30/08/2012 - Automotive Innovations Torque Up Manufacturing Revival
- 31/07/2012 - Torque of a Motor Revolution
- 12/06/2012 - Torque test ensures reliability of steerable drills
- 30/04/2012 - Engineers Torque Technology To Medics
- 29/03/2012 - Long Service Motors Tested after Re-Engineering
- 01/02/2012 - Back Manufacturing, But That Is Only Half The Story
- 23/12/2011 - Pay as you Sense
- 02/11/2011 - New wave and tidal turbine concept promises clean, affordable energy
- 05/10/2011 - Ground Crews talk sense on Generator Maintenance
- 08/09/2011 - TorqSense transducers help to guarantee valve actuator performance
- 08/08/2011 - Company Profile
- 11/05/2011 - Sensing growth opportunities
- 25/03/2011 - Drama as Helicopter sensor flies into Theatre role
- 07/02/2011 - Technology transfer tests tree safety
- 18/01/2011 - Sensor Technology helps to keep sheep shorn
- 02/12/2010 - Smart Load Sensor
- 13/10/2010 - Novel sensors aid tidal turbine development
- 01/09/2010 - Torque Sensor helps reduce engine friction
- 12/08/2010 - Tidal Turbine to light the Thames
- 22/06/2010 - Sensor Technology Provides the Key to Learning
- 05/05/2010 - Talking Sense About Technology Transfer
- 16/04/2010 - ULTRASOUND HELPS OPTIMISE DRIVE DESIGNS
- 08/03/2010 - Ensuring accurate feel to Power Steering
- 12/01/2010 - Iron Bird with lightest touch
- 16/10/2009 - Sensor hones in on sharp operators
- 03/09/2009 - Testing time for business Jet
- 10/08/2009 - Non-contact torque sensor now mounts in moments
- 09/06/2009 - SAWs: A Cutting edge technology from Sensor Technology
- 23/01/2009 - Torque improvement for handling accuracy
- 03/11/2008 - Servo research points the way to improved dynamics
- 29/08/2008 - Sensor Technologys' TorqSense shows it's safer to belt up than previously thought
- 30/07/2008 - Nuclear engineers avoid contact with Sensor Technology
- 27/05/2008 - The Future of Green Cars lies in Sophisticated Testing
- 11/03/2008 - When two is better than one
- 19/10/2007 - BIG PUSH TO RECYCLE PLASTIC
- 12/09/2007 - Intelligent Extruder plans its' own growth
- 10/08/2007 - UAV takes fast track to altitude