Wednesday, 2 October 2013

Day 7 - 2/10/2013

Today we finally completed our vertical wind turbine. All we have left to do is mount it onto the pole and complete our PowerPoint presentation. We made the bottom and top supports for the rotor and hub. Once again it involved a lot of machining. Due to freestyling most of our design, we had to do a lot of moving and screwing/unscrewing to get things perfect. Once everything was in place and welded we carried it out to be mounted but it was late in the day and we decided to just wrap it up and return next Monday 7th October.

Final stages of the wind turbine

Bottom support of the turbine.

Bottom support: Plate that connects support to the frame.

Cleaning the stator which was covered in metal shavings.

Daryl tidied up the magnets on the hub which also were covered in shavings.

Damon removing the lip from the stator so it fitted snugly onto the plate.

Kieran and Gary working together to fasten the plate to the frame.

Bolting the start on.

Close up view.

Peter (tutor) machining down the top support for us.

Peter is a great guy.

Kieran grinding some box steel into shape to be the middle arm/support to fit onto the pipe nicely.

Hub on the stator and starting to take shape.

Cutting the middle arm/support to size.

Final welds on the turbine before we are finished.

Tuesday, 1 October 2013

Day 6 - 1/10/2013

Today we started making the arms and plate for the segments of barrel to be connected to the rotor. This involved quite a lot of machining and time. We used 3 pieces of square steel, steel plate and right angled brackets as teeth to grip on to the hub.

Joining the wind turbine together

Gary grinding down some jaws to be connected to the hub.

The 3 arms ready to be welded.

Marking out 120° for each segment/arm

Arm bolted to the vane ready to be welded to the plate.

Monday, 30 September 2013

Day 5 - 30/09/2013

With today being the first day of the holidays we got a lovely extra hour sleep in. We began by dividing the 40 gallon drum into 3 segments. This was a challenging task as we were mainly guessing where the center was based on the 3 even points we marked out. We drew a triangle between all 3 points and then measured the length of the lines. They ended up being 500mm. So we marked 250mm on each line and drew a line from each corner of the triangle to the opposing middle mark. After all of the sides were marked we each cut a segment with a cutting disc as only Gary, Darryl and I were present today. After that we smoothed off the cuts with a finishing disc. Then we faced the problem of how we would hold the barrels together. Damon suggested we bolt them close together so we went with that design only to face the problem of mounting the stator onto the barrels. So we grinded off the welds and will start rewelding the segments onto arms that will connect to the casing. 

Building the turbine

Gary using the finishing disc. 

Preparing the segments for welding.

Darryl grinding off the welds. 

Monday, 23 September 2013

Day 4 - 24/09/2013

We started the day by finishing off soldering the cables to the stator and setting up the photovoltaics to charge the batteries. We then came to the hypothesis that by having all of the class' projects connected onto the bus, the bolts/terminals would not be big enough to be permit all of the cables, so Kieran and Gary went to see Bernie (Mechanical Fitter tutor) about modifying bus bars for us. In the end he just gave made new brass connectors for us and they fitted perfectly. We then decided to put a rope in the pulley on the post so that when the time was needed we could erect the vertical shaft turbine. Once that was done Gary rigged together a few diode boards and attempted to build a 3 phase rectifier. For some reason he decided to plug it into the work benches at 400V and blew up 3 of the 8A diodes. After revising his mistake he has successfully created the 3 phase rectifier. When the batteries were fully charged we managed to run the G.T.I. for 8 minutes and 14 seconds which was impressive as we were just using the photovoltaics and today was a very overcast day. After the batteries were discharged, we hooked them back up to the photovoltaics and got the batteries charged and ran the G.T.I. for a second time. This time we lasted 8 minutes and 30 seconds. For the rest of the day we were brain storming on which design to use for our wind turbine.

Finishing of rewiring the stator

Darryl soldering the final wire on.

Beautifully soldered cables.

 Completed rewired stator.

Modified Bus
 Modified, more efficient 24V Bus.

Putting up the rope

 Kieran putting up the rope whilst Gary spots.

3 Phase Rectifier

 Circuit diagram of what was done.

Day 3 - 23/09/2013

Today we began by crimping the ends of the photovoltaic cell leads with female crimps and then 2.5mm² TPS with male crimps so that they could easily be connected and disconnected as stripping the cables continuously would not be ideal as we'd eventually run out of cable length. Due to the solar charge controller being still in repair, we had to connect the solar panels straight on to the batteries. The only problem with this was that when the batteries were fully charged they would continue to be charged until disconnected and this could result badly so we had to monitor the amount of voltage the batteries had. We also connected an ammeter between the TPS and the batteries to measure how much amps the cells were producing. The process of charging the batteries with just the photovoltaics was a lengthy one so we headed off to an early lunch. Before leaving we gave feeding the class a test run with the batteries on about 25V but there just wasn't enough charge in the batteries. When we returned, the batteries were sitting just over 26.5V so we had a bit more waiting to do. When they finally reached full charge (28V) we turned on the Inverter, Battery Bank and G.T.I. and we successfully fed the classroom but only for about 2-3 minutes. Due to slack team members, Tutor Andrew Massie prescribed us another grueling task: A vertical wind turbine. The equipment for this from previous years are broken and it's just less time consuming for us to start from scratch. So far we are in the process of rewiring the stator as it is currently rated for 230V and we need to get it to 24VDC.

Revised project plan

Photovoltaics test run

Crimped photovoltaic leads.

Insulation taped female to male crimps for added safety (what Chenergy is all about).

Tutor Andrew Massie going for a stroll and our photovoltaics at work.

DC Voltmeter on 30V range. Measuring battery voltages.

DC Ammeter on 25A Range. Measuring input current.

Successfully feeding the classroom/grid.

Starting on the Wind Turbine

Gary sanding off the enamel from the copper.

 Darryl preparing the copper for rewiring/soldering.

Soldering the copper. 

Close up shot. 

Monday, 16 September 2013

Day 2 - 17/09/2013

We started the day by fixing up the hinges on the photovoltaic cell containers as the wood split on it whilst we were putting away the panels yesterday. This was quite time consuming because we were limited on working space as the wooden framing was in the way. During the time we were doing that, Darryl was drilling a hole through to the classroom and fitting some conduit for us to run the cables from the solar panels (outside) to the 24V Bus (inside). To begin we were using 1.5mm² 2C TPS as the solar panels are only 240W at 24V so they would draw no more than 11V (P=VI) and 1.5mm² is rated to 17Amps. However, we didn't put into considering the volt drop and switched it over to 2.5mm² 2C+E TPS. EMF were unable to handle their work load and gave us permission to set up the 2KW inverter and 24VDC Bus. We test run the Grid Tied Inverter from the 24V bus but the batteries were too discharged to show us any positive results so we must wait till we get back the broken Solar Charge Controller so we are able to charge the batteries.
Replacing hinges

Unscrewing the hinges to be moved to.

Repaired enclosed photovoltaic cells. 

Photovoltaic Cells conduit


Neatly mounted conduit for photovoltaic cells running from outside to inside.

The connection between the conduit and classroom.

Kieran pulling TPS through the conduit out into the terminal block. 

Conduit coming from outside into classroom.

Neat and tiny conduit going from photovoltaics to the 24V Bus.

Final part of conduit going to the 24V Bus.

Doing EMF's dirty work

Reworked 24V bus and used a 16mm² Single core link between the batteries as the 1.5mm² link was not handling the current well and the cable got very warm.

We wall mounted the 2KW inverter as it was the aesthetically pleasing option. 

Test running the G.T.I. on 24V Batteries

The agonising minute wait for the G.T.I. to start.