Three years gone, Six months to go… (almost anyway)

I remember being told by my Mum that the road to hell is paved with good intentions. And all my good intentions at the time last year to blog bi-weekly definitely have made my path to the hot place a little bit more easy. So, in penance and to try blogging again here we go.

A lot has happened since September last year, and I'm not quite sure how best to do this, so I've decided to give a bit of photo diary of the last 12 months to give a taste of what's been going on both in PhD-world and my own.

In October/November I was working on the stability analysis of parallel inverters, using small signal stability analysis, the results of the analysis match the simulations relatively well, hopefully these will also match the experimental work as well. Below is the pole-zero plot for the parallel inverters.

Pole-zero plot for parallel inverters

I met one of the founders of Learning Planet, Justin Wickham, in London to discuss the pico hydro scheme they are looking at. You can see more of the area Learning Planet are in here or have a look on their website www.learningplanet.org.uk.

 

The School in Dhawa renovated by Learning Planet

My cousin Helen got married at the end of October, so we headed over to Ireland to celebrate.

Helen and me at her wedding

I helped on the sound desk again with Horfield Theatre Company for their October pantomime, Franky Panky and had a lot of fun - with innuendo and a lot of childish humour. I'm getting a little bit better on the sound, although every so often the wrong person's mic would be turned up… A fun fun week nonetheless!

Franky Panky's Poster

I had a "cruise" to Bruges with my little sister, which was fun - especially all the chocolate!

Me and a bear in Bruges

During November and December I wrote a paper on the experimental turbine work I'd been doing, and submitted it to the Journal of Applied Energy at the beginning of January. It was finally accepted in June, and published here in July! The paper that I presented at WREC was also published in Renewable Energy Journal in July this year as well, here.

A figure from the Applied Energy journal, the slug of water that's ingested by the turbine in one rotation

In the last weekend of November, Hannah and I went to Salisbury to celebrate two years. We had a fun couple of days and saw Stonehenge, the Cathedral, Avebury and the Uffington White Horse.

The Stone Circle at Avebury

I spent Christmas with my parents and sisters, which was great.

With my family at Mount Edgecombe

Back in the lab, I started working on an improved control system to try and reduce any current spikes when the two inverters connected together so that switches won't go bang when the inverters are connected to a grid. This improved control did what it was supposed to in the simulation.

Reduced current spikes on paralleling inverters

I had another family wedding in Ireland, my cousin Gillian got married in early February and Hannah and I headed over for the weekend. Unfortunately snow made our journey back delayed… (I blame Gillian's sister, Jenny, who flew back with us!)

Gillian and Alex's wedding

I found an IEEE conference in Kathmandu that would take place in late September, known as ICSET. I wrote two papers for this conference, one on the turbine testing and the other on a simulation of a off-grid pico hydro network, submitting them by the end of March, which were approved. I'm off to Nepal on the 17th September, which is going to be amazing.

A simple model of an off-grid pico hydro network

I also attended and presented at the EWB research conference at UCL at the end of March, adding to the stress at the time, but really enjoyed it and was interested to hear some of the other projects going on in the EWB universe.

AC grid with distributed generators connected with inverter front ends

After submitting the papers, Hannah and I went off to India for two weeks, and had the most fantastic time. We spent a week in Kerala and a week in Bangalore, and had some amazing experiences, spending a night on a houseboat, riding on an elephant, and visiting some beautiful parts of the countryside.

On a houseboat in Alleppey, Kerala

On returning from India, I started to build some electronics, starting with a simple inverter, four switches and an inductor-capacitor filter. I built a simple control circuit in analogue components to control the output current to a reference sine wave from a signal generator. The circuit managed to produce a relatively good output.

Inverter Mk1 and Output

At the end of April, Hannah and I went to see one of my favourite bands, Feeder, in Cardiff. They were absolutely amazing. Enough said.

At the Feeder gig

By the beginning of May, it was time to do 'Living Below the Line' again (see last years version here). We raised money for MRDF and this time, there were a good 10 of us that did it.

Pasta Dinner during Live Below The Line

Once the original inverter worked, I built a second checking it worked with the basic controller, and then used a real time controller called dSPACE which can use MATLAB models to control things, allowing quick changes to be made to the model and be able to see the result of it. Both inverters worked controlled by the dSPACE which was great.

Parallel Inverters with dSPACE

The Olympic Torch came to Bristol in May, and we went down to the Harbourside to see it. The city was buzzing, and we had a fantastic time watching it arrive.

Olympic Torch arriving in Bristol

I ran a quick tour of the Hydrolab for the University of Bristol's Open Day in June, and showed some of the potential new students around and demonstrated the turbine rig. By the end of the day, my voice was hoarse, but had talked to many hundreds of people.

Turbine rig running

Obviously with London holding the Olympics, I wasn't going to miss going to see some events. We went to see the Beach Volleyball on Horseguards Parade and some Hockey in the Olympic Park, just a most fantastic experience.

Beach Volleyball at Horseguards Parade

Once each of the inverters worked individually, I connected them together, to see how they would work in parallel. They synchronised without blowing up, which was always good, and now in my work I'm trying to improve the performance of the system.

Parallel inverters

Every year Bristol holds an International Balloon Fiesta in Ashton Court, on the outskirts of Bristol. We went to the Nightglow, where the balloons light up to music, and saw a mass take off with Tim, who had come over from New Zealand.

Balloons at the Nightglow

We had a few days in Cornwall, camping. It rained, well it was Cornwall after all, but had a few nice and sunny days, especially down on the Lizard and ate some rather tasty ice-cream too…

Lizard Lighthouse in the sunshine!

A couple of weeks later we returned to Cornwall for a school friend's wedding. Again it rained, and it didn't really let up this time. Argh. Still, we enjoyed an ice-cream in the rain.

Hannah eating an Ice-cream in the rain at Lanhydrock

As well as the Olympics, we also got some tickets for the Paralympics, this time for the swimming, athletics and also saw some judo and table tennis. If anything, we enjoyed this more than the Olympics, the atmosphere was just incredible.

The long jump in the Olympic Stadium

And straight from the Paralympics we headed to the Small is Festival 2012. I had been asked to do a little workshop on pico hydro, and so designed a workshop to build a little crossflow turbine and test it, the workshop went really well and I had a very inspirational weekend. And it didn't rain!

The workshop at Small is Festival

So, hopefully now you're all about caught up with me and my life. I'm really sorry it's taken so long to do this, but I hope I'll be a bit more regular. Not long to go with the PhD now either. Times are scary and fun!

SAM

Two years on

I can't believe it's almost October again. Another academic year has started and this means not only another new intake of fresh meat for the university, but one year less of my PhD. Time doesn't half fly. According to my plan I made at the end of last year, I'd have built a system and be testing it now, and then after Christmas being saving the world. I have a feeling that might not happen now though.

As not much photo-worthy has happened over the last few weeks, I've included some of my favourite photos from the last year here, ones that I've not put in any blog posts before.

An advert for Tena Men I saw in a service station toilet, it made me chuckle a little...

I have to say the work I've been doing over the last few weeks hasn't been the most exciting in the world. I've been writing a paper on the Turgo testing I had done over the June and July. The paper's been quite difficult to get on with, as there have been several gaps I've needed to fill in. Well, not gaps as such, just bits that make the paper read better. At the moment it sounds a bit like a bad GCSE science report - I did this, then I did this, then I did this. A little bit disheartening, but with a bit more work I will hopefully getting it reading a lot better.

The inside of L'Arc de Triomphe, as seen during our trip to Paris last November.

Apart from writing a paper, I've spent a lot of time reading papers. In fact I'm in the process of sorting through over 60 papers that have different methods of droop control, that can be used to help connected inverters into parallel. The problem I've found is that there are a few different methods, with several people publishing papers on each different method. Some of them have slight tweaks which makes the method different, an extra term in the equation here or there, a slightly different mathematical relationship. But I'm not really sure how many different adaptions there are to each one. So the aim of the exercise is to identify as  many different techniques as possible and record the salient points from each and then chose which ones to take forward into a model. This is going to take me a few more weeks, but I'm hoping it will be a worthwhile exercise. Fingers crossed!

Looking out to sea during our stay at the Lighthouse near Lynmouth with my church friends in January.

A birthday cake for Hannah's friend Lydia - I was quite proud of this one, as it was modelled on Lydia's cat Patch.

This month we also had our Harvest Messy Church. These are every quarter, and pretty much every time I cook, principally because it means I'm well away from kids then (slightly loose tongue + children = problem). I also actually really enjoy cooking, and rarely get a chance to cook for a large number of people. We normally cook for about 80 people, and this time we made a soup, packed full of British harvest vegetables. It was good fun, and I was surprised how many of the children actually enjoyed it. Some even came back for more. Who says children don't like good healthy food?

A white rhino we saw in Longleat Safari Park, during the joint birthday trip in March.

Today, I was invited back to Atkins, where I worked before starting my PhD. My friend there, Marie Adeyemi, was going to launch a program called Atkins Aerospace CARES, a corporate social responsibility initiative. Marie has done a fantastic job in convincing the management at Aerospace to allow this to go ahead, and even give the project a budget. They hope it will get Atkins people linking up with charities and NGOs, doing pro bono work and consultancy for them and encouraging a better team spirit in the company. Part of it is to encourage people to take sabbatical's, rather like me. I felt a bit awkward as I had left once I returned from my sabbatical year. However, it was great to see everyone there again. There were some faces I knew and some I didn't. It's strange how it sometimes feels you haven't left at all. Especially when the receptionist asked me if I had just forgotten my pass again (a rather usual occurrence for me!).

My eye, the wrinkles are really starting to show now…

Looking back, this year has been busy, and I've achieved a lot. I've presented at a conference, winning best paper in topic, I've built a small turbine and tested it, getting an amazing efficiency, I've travelled many thousands of miles including two trips to Nepal. However, time doesn't stop. I've got so much more to do in the next year, and if I don't get it done, then i'll be in real trouble. So, here's to the next year being productive, fun and memorable!

SAM

Back to work…

After the excitement of being in Sweden, the last couple of weeks have been fairly boring. Work has been mainly consisted of testing, I've been doing a more accurate test regime, looking at the extremes of all my variables to see which are most important and which may affect the efficiency of the turbine most. To do this, I've had to modify the rig slightly, so I can more accurately measure and move angles and positions. I've a series of 12 tests to do now, which will map out the combination of variables that is most important. This should be finished in the next week hopefully…

I've also been getting further frustrated by the analytical modelling. I still seem to unable to model it using the different physical effects that are quantifiable. I've tried another method over the last couple of weeks, using the cup as the stationary coordinate system and sweeping a stream of water particles in and out, but that still brings up inconsistencies which I really can't get my head around. I think the only option I really have open to me now is use experimentally derived constants to match the theory with the experiments. Definitely not ideal and not really what I wanted to do, but I will do this so that I can have a model to progress on to the next stage and then try again later to derive the whole thing from geometry and fluid mechanic equations.

I've also been looking at the electrical side of the project a little more. At WREC I met someone who presented a paper on parallel connected inverters and he gave me some pointers about how to model these types of systems, so I've done a lot of reading on these and the concept of virtual impedance control schemes for inverters.

On the more fun side of things, I've been getting ready for another musical, this time Sweet Charity with Bristol Musical Comedy Club (BMCC). This is the first time for a long time I've worked with a new company, which is fun, although getting to know how different people do things is quite hard at first. BMCC don't have a parish hall that they're based in, so perform in professional theatres, this time it's the Redgrave Theatre. This is going to be another new experience for me, setting up and working in a proper professional theatre. I've spent the last few weeks visiting the rehearsals and building some of the set, which has been good fun - I enjoy getting my hands dirty, it makes sitting at a computer for the rest of the day more bearable.

I went down to Cornwall for a few days for my Mum's birthday, which was great. I really haven't visited home as much as I should have over the last few months, so it was fantastic for all my family to be in one place again.

Mum and her birthday cake (don't count the candles!)

The next few weeks are going to be fairly hectic I think. Alongside all the work I'm doing at uni, I'm off to Paris for my friend's 'this-isn't-a stag-party-it's-more-of-a-pre-wedding-bash', then there's the performance of Sweet Charity in the first week of June, straight after coming back from Paris, then after a week's rest and relaxation, I'm off to Nepal for a short visit to go to Rachhu's wedding before returning for three weeks and then back to Nepal for my annual month-long trip. I've got to try and wrap up all the turbine work before I head away as they're going to be doing some modifications in the Hydrolab, which is annoying. Finger's crossed it all goes well!

SAM

Frustration

I went to Longleat Safari Park and Adventure Park at the end of March to celebrate my birthday. So to break up the endless monotony of my writing, I've included some photos in from that.

Longleat house

It's been a tough few weeks in the PhD front. I've done a few runs of the turbine in a couple of positions and got some good torque and power outputs from the turbine. However, when they're compared with the model I've got, they are around 20% out. There are several explanations for this, as discussed last time - see here. However, I've still not been able to rectify these problems over the last couple of weeks and it's been really starting to get on my nerves. It's so frustrating, working on a possible solution for 2 or 3 days then ending up at the same point that I started with. I am determined not to let this get the better of me. So I'm going to try some different methods for modelling and also look at changing my rig a little to see whether there are some things that are causing the model to be very different from the actual results.

Feeding the deer - they were smelly, dirty and very greedy

A warning sign…

I attended a lecture at Bristol University run by Water Aid for World Water Day. There were two speakers, the first from Aquatest, a research group supported by the Bill and Melinda Gates Foundation. They are developing a water testing device that can simplify the detection of pathogens in water. The second speaker was from a new charity called Wellboring, looking at boring wells in Kenya. I have to say I was a little more sceptical about this charity, their intentions were perfect, but their delivery was to just give a community water, there didn't seem to be the sustainability there - it seemed an almost imposed solution - however, I'm sure that they will be successful and they will help many many people and I'll be forced to eat my sceptical words!

A resting lion

The seals jumping for food

I've also had a bit of busy few weeks at church. I produced another talent show in the middle of March in the church under the guidance of several people. We had a very good evening, with some fantastic singers such as Alice Lovell and for once the Scouts provided entertainment rather than just embarrassed laughing. I even did a short poem recital (Roald Dahl's The Pig) as I wanted to get up on stage - my vanity appearing again. We raised a fantastic £170 for the church, and now are going to get ready for the pantomime… We also had the Easter Messy Church, which we had 86 people at. At our messy church, my job is to do the cooking along with Hannah and Becky - I'm not really trusted around children due to my slight potty mouth - and we cooked 15 pizzas in a small oven. We had a panic when all the pizzas stuck to their pans and we couldn't get them out without making most of them disintegrate. So, for an hour we slowly pulled pizza away from pans, and after a stirling effort we finally managed to serve up all the pizza to the hungry punters with very respectable looking food. This was also the first time that we've manage to have all the food eaten - must have a been good!

The hedge maze (we managed to get through it in under 30 mins!)

For those who don't know me, I love to make cakes. For my birthday this year, Hannah made me three most amazing cakes. I spent the days after my birthday feeling sick from cake but somehow not being able to stop myself from eating them. So, for Hannah's birthday the week after mine, I had to try and match hers. I spent an evening baking cakes, and the next day I carved and iced her cake. I had made a Lego-man. I don't think it was as good as last year's effort - the hungry caterpillar cake - but it went down well.

My fantastic birthday cakes!

Legoman cake

Last year's effort - The Hungry Caterpillar

After all that cake, I'm rather more round and weighing a few more kilos than I probably should be. So the next month I'm going to be going on a bit of a healthy eating kick, in an effort to lose some of the cake weight and try and save a bit of money as well - this year's trip to Nepal is not too far away now!

For now

SAM