Successful Endeavours - Electronics Designs That Work!

Green Electronics


Powering Telemetry

A big issue in the world of the Internet of Things, or IoT as it is abbreviated, is how to get power to remote devices. And this splits up into 2 separate but definitely related problems:

  • the power source
  • the power consumption

Obviously, if the power consumption is high, the power source has to be capable of providing a lot more power. We looked at this in our IoT – Remote Telemetry Case Study. So let’s tackle that one first.

And the focus for this article is remote devices using Solar Charging. Before we look at that specifically, let’s understand the problem.

Power Consumption

There are multiple ways to reduce power consumption. These were covered already in Reducing Power Consumption and Reduce Power While Awake with examples given in Sleep Saves Energy.

Low Power Sleep Mode

Low Power Sleep Mode

The short version of this is that you have to do 2 things at the same time:

  • reduce the average power that is consumed all the time
  • reduce the energy required to process an event

The first of these is also known as Quiescent Power Consumption. This is the power consumed just running the system when it is doing nothing, or close to it. At a minimum, the Power Supply has to deliver this amount of power just to make sure that we could react to an event, should it occur. And I can hear you thinking that it is hard to get this low enough and still have a responsive system.

Correct! But you have to have at least this amount of power or Game Over!

Which is where the second part comes in. You also need some power to respond to events. These can be something you need to log, or reports you need to post. If you are uploading to a web service using cellular communications, the peak power consumption can be very high. So you have to minimise this time.

We would normally model both of these and work out a power budget based on the worst case scenario model. Excel is a suitable tool for doing simple modelling of this as well as scenario modelling.

But I can hear you thinking “why worst case“? Answer: “Because you want it to always work, not just work on average“!

Telemetry

Telemetry means measurement at a distance or remote measurement. So you are measuring something at location A, and want to know the value of the measurement at location B. This implies the 2 locations are not close enough together that this is a trivial problem to solve.

In our world, Telemetry can mean anywhere on earth, though our customers are usually in Australia. In NASA’s world, (maybe world is the wrong term for them) it can be anywhere in the solar system. Voyager 1 is currently more than 18 billion Kilometers away and has been active for 40 years.

Artist's concept of Voyager in flight

Artist’s concept of Voyager in flight

The challenge for low power consumption, is how to get the measurement from location A back to location B?

Solar Charging

The NASA solution is simple. Near sun facilities are Solar Powered, and the rest use some form of nuclear power. Since no-one will ever let us nuclear power any Telemetry device, and I’m Okay with that, and we are near enough to see some sun, we will follow that option instead. And besides which, we can do it in our office and not a heavily shielded facility.

So lets recap on what we know about solar charging:

  • ignoring the energy cost of making a solar panel, the energy cost is free after that
  • there is a maintenance cost which includes cleaning panels
  • provided the construction is robust, they are a long life product
  • you have to do Maximum Power Point Tracking (MPPT) to harvest the most energy or minimise the panel size

And to get more power from a solar panel, you have to:

  • have more sun
  • have a better angle to the sun (cosine reduction)
  • have a better MPPT
  • handle lower voltages
  • use the right silicon

Not all Solar Panels are equal. If you want you panel to work in a mostly shady place then you might also want to use mono-crystalline Silicon solar cells because they are efficient and can continue to convert even low levels of light. In recent developments the efficiency of conversion had passed 25% as reported in Efficiency of Silicon Solar Cells Climbs and some of the stacked cell technologies are past 40% efficiency.

compact solar cell

compact solar cell

And then you have to harvest that energy. Which is where new devices like the SPV1050 come in. Experiments in our office showed that we can charge a Lithium Polymer battery from the internal lighting. And it is a buck boost converter meaning that it can charge the battery in full sunlight (reducing voltage) and also moonlight (increasing voltage) and the device costs less that $2 in 1K pieces.

I only have on criticism. The super low quiescent current LDOs would have been more useful if they were fully independent because this would have taken another item off the Bill of Materials.

Primary Cells

The other option for Telemetry is using Primary Cells. These are not rechargeable and so must last the life of the product. We currently deploy Cellular based Telemetry modules that can run for up to 10 years from a Lithium Primary Cell or 5 years from Alkaline Primary Cells. This is ideal for Smart City style projects where the devices might be moved as they fulfill their current purpose. A good example of this is people metering or pedestrian counting where a council may want to know how much use an area is getting. Once that is understood, the Telemetry module can be redeployed and since it isn’t connected to mains power you don’t need an electrician to do that. Or they could be used to understand the level of demand of public transport services in real time so you can adjust capacity on the fly.

So there are options and as technologies like NB-IoT and CAT-M1 come online the power budget for cellular communications continues to fall. We covered this in Cellular IoT Communications. And as of last month, Telstra turned on CAT-M1 across the 4GX network.

Quectel BG96 CAT-M1 Module

Quectel BG96 CAT-M1 Module

Successful Endeavours specialise in Electronics Design and Embedded Software Development, focusing on products that are intended to be Made In Australia. Ray Keefe has developed market leading electronics products in Australia for more than 30 years. This post is Copyright © 2017 Successful Endeavours Pty Ltd.

Putting Light to Work

Light is a really interesting thing. It has so many different aspects. And it took us a long time to work out exactly how it functioned. And in many ways that is still an ongoing process. So this post is a brief survey of some recent advances in our understanding of light, how to use it, and how to generate it.

Extracting Energy from Light

Recent advances in Quantum Dots have taken us one step closer to improving our extracting of energy from light and Solar Cells continue to improve.

Quantum Dot Solar Energy Conversion from Windows

New record for Solar Cell efficiency

Interactive chart of Solar Cell technologies and inefficiencies

The chart below is from the link above and shows that the fastest improving Solar Cell technologies (the 2 steepest red lines) are Perovskite Solar Cells and Quantum Dot Solar Cells. Click to get a larger version. Or go to the interactive link where you can get more detail for each dot.

Solar Cell Efficiencies - By Time And Technology

Solar Cell Efficiencies – By Time And Technology

And for a good summary of PV (PhotoVoltaic) technologies the link below provides a useful guide.

What makes a good PV Technology

So apart from turning the light in electricity, what else can we do with light?

Light for Communication

Light is also useful as a communications tool. And recent advances in Quatum Dot management of light means it could hold the key to higher levels of computing power in the future, as well as more secure communications.

Quantum Dots set speed record for switching

Phototonic Hypercrystals improve light control

Photonic Hypercrystals

Photonic Hypercrystals

Saucer Shaped Quantum Dots improve LASER brightness

2 steps closer to a Quantum Internet

The last link is particularly interesting because it involved entangling photons at a distance. And the first experiments have already been successful.

Quatum Entangled Photon Communications

Quantum Entangled Photon Communications

But is there more?

Other uses of light

As it happens, yes there is.

Nanoscale structure purifies water using light

Artificial Photosynthesis extracts CO2

So this remains a very busy space.

Successful Endeavours specialise in Electronics Design and Embedded Software Development, focusing on products that are intended to be Made In Australia. Ray Keefe has developed market leading electronics products in Australia for more than 30 years. This post is Copyright © 2017 Successful Endeavours Pty Ltd.

LED Street Lighting

With concern for rising global emissions and the majority of the worlds power still generated by burning fuels of one kind of another, the replacement of older street lighting technologies with higher efficiency and longer life LED Street Lighting would appear to make sense. And on the up side, everyone agrees that the longer life of the LEDs compared to other lighting technologies is a huge plus.

However, it turns out to be not as simple as that. In LED Streetlights Are Giving Neighborhoods the Blues the author, Jeff Hecht, points out a few other issues to consider. The picture below graphically demonstrates one of them.

Modern Street Lighting - Aerial View

Modern Street Lighting – Aerial View

Colour Temperature, or how warm or cold a light appears to our eyes, has a significant impact on how we perceive the lights. Above we see very white looking LED lighting alongside more traditional High Pressure Sodium lamps. The much bluer LED Street Lights cause several serious issues including:

  • actually reducing our ability to see clearly at night
  • disturbing noctural creatures more (eg. hatching turtles)
  • affecting sleep patterns
  • affecting biorythms
  • decreasing our ability to see stars at night

So the energy savings are real, but the environmental side affects are too.

Managing Colour Temperature

Unfortunately LEDs are not as easy to control for Colour Temperature. Unlike an incandescent light, they emit a very narrow band of wavelengths of light. And most White LEDs emit blue and use a phosphor to down convert some of the Blue to Yellow so they look whiter rather than Bluer. The earliest White LEDs were very blue and so early adopters of LED Street Lighting have ended up with the worst outcome. And the more we warm up the colour the lower the efficiency because we lose some energy in the down conversion.

The are some breakthrough underway and Cree have recently discovered that it is more efficient to add some red LEDs to the mix to drop the perceived colour temperature. And this is helping. But even the newest devices are at a colour temperature of 3000K and the High Pressure Sodium Lamps are at around 2100K. So still quite a bit different.

The only solution for the millions of already installed LED Street Lighting is unfortunately to swap them out for more recent LED arrays that are at a better colour temperature.

Successful Endeavours specialise in Electronics Design and Embedded Software Development, focusing on products that are intended to be Made In Australia. Ray Keefe has developed market leading electronics products in Australia for more than 30 years. This post is Copyright © 2016 Successful Endeavours Pty Ltd.

Batteries Today

There are 4 separate drivers for current battery technology:

  • Cost
  • Size and Weight
  • Capacity
  • Recharge rates and cycles

An example of an emerging industry for batteries is electric vehicles. These require high recharge rates, high capacity, high recharge cycles and acceptable weight, size and cost. So the current front runner in commercial batteries, the Lithium Ion battery, has some challenges meeting these requirements. But it is also the best we have right now.

Adding Super Capacitors

One approach to improving battery performance in peak demand situations is to add a Super Capacitor in parallel with a conventional lead acid battery. The Super Capacitor smooths the energy demand by delivering the high current needed for peak demand and the lead acid battery provides the bulk energy storage.

CSIRO UltraBattery Inventor - Dr Lan Lam

CSIRO UltraBattery Inventor – Dr Lan Lam

The CSIRO developed UltraBattery is a good example of Australian Technology Innovation in next generation batteries. It is one example of their work in Energy Storage. And also good example of their partnerships with industry to bring next generation technologies to commercial reality.

New Battery Technologies

The front runner for the next generation of battery technologies is the Lithium Air Battery. This promises double the energy density per unit volume of Lithium Ion Batteries but at 20% of the weight. So ideal for Electric Vehicles where weight is one of the critical elements.

Lithium Air Battery Chemistry

Lithium Air Battery Chemistry

The reason this is such a promising technology is because it has:

  • high recharge efficiency (90%+)
  • high recharge cycles (>2000 versus 300 for some Lithium Ion batteries)
  • high energy density
  • low weight

So what is the catch?

Researchers believe commercial versions of this battery technology are only 10 years away. That isn’t that long for a new battery technology. The hurdles they still need to face are primarily in protecting the pollution from corroding the metal electrode and preventing dendrite growth which is an existing problem with Lithium Ion Batteries. The electrode wants pure oxygen and is corroded by moisture, carbon dioxide and nitrogen. So some challenges remain.

Using Existing Batteries Better

The other approach is the one we usually take. Use Existing Batteries Better.  This involves better power management, better battery management and rethinking the whole solution to a problem. We showed an example in a recent Remote Telemetry Case Study we did in the Internet of Things space where we took an installation that would have required a 200W solar panel and instead deployed a system that runs from 4xAA batteries for 2 years. The next step is to add an energy harvesting component with a suitable rechargeable technology to take the battery maintenance interval from 2 years to 5 years. Even with the best and most durable rechargeable battery technology around today for regular commercial applications, a 5 year maintenance interval is still needed.

So multiple approaches. I’m looking forward to the next set of breakthroughs in this area. Including marrying the CSIRO Super Capacitors with a Lithium Air Battery.

Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2015 Successful Endeavours Pty Ltd.

Local versus global electrical power

Up until recently, AC Power Distribution was the most efficient way to move electrical energy about. But right back at the beginning of electricity, it wasn’t obviously the case. Thomas Edison had favoured DC voltage and current distribution but was defeated commercially by almost all other comers because the technology to do AC Voltage Transformation, the transformer, was just easier top make than a DC version based on the technology of the day.

Thomas Edison

Thomas Edison

You can read more about this era in the War of Currents. This was the 1880’s of course. Probably the highest fundamental invention decade so far. But that is for another post.

Modern DC Power Distribution

Wind forward more than 100 years and the technology to transform DC voltage and current, at high efficiency, is mainstream. Of course the incumbent AC infrastructure is wide spread and not easily displaced. But DC is winning ground in new installations.

In Australia, Basslink is connecting Tasmanian power generators to the Victorian electricity grid using HV/DC or High Voltage DC Technology. It is now the technically superior offering.

World Power Grid

And so the new opportunities open up for sharing power across the globe. The current plans are just for grid connect. But if you consider renewable energy as a major contributor, if we have a globally connected grid then the solar power generators sun side can be supplying the night side communities and 12 hours later the other way around. If solar goes global and the grid goes global, then the fluctuating and time of day dependent power generation can be balanced out globally. What we can’t make economic in a single region, can suddenly become overwhelmingly compelling across the globe.

That will require quite a lot of collaboration and market trading beyond what has traditionally been possible, but the pay off would prove worth it. I am going ahead of what we can currently do, but I also believe this is where we have to get to.

Global Power Grid

Global Power Grid

For more information on the current state of play, check out the IEEE article on Let’s Build a Global Power Grid.

And you can be sure we will be doing all we can to support the push.

Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2015 Successful Endeavours Pty Ltd.

Internet of Things

The Internet of Things, or IoT as it is abbreviated to, is still an emerging trend. But it is driving some substantial changes in some industry areas. This includes the 4th Industrial Revolution, also known as Industry 4.0.

If you are deploying to a factory or industrial complex, then generally the networking and power is already dealt with and you can piggy back off the existing infrastructure. But what about deploying Remote Telemetry? If you wanted to measure water tank levels or water usage in a rural location you might have to use a solar powered or primary battery powered system and 3G or 4G communications to get the data back to a website or server. That can have its own challenges. The typical industrial computer used for these monitoring tasks and posting reports or transactions requires a lot of power to run and is expensive. So can you do it if the budget for the hardware is $600, you don’t want to use solar cells and also don’t want to change the batteries every month?

The answer is YES. Check out this short video to find out how.

The awards referred to are covered in our recent posts on the National Manufacturing Week Endeavour Awards and the Process Automation and Control Electronics PACE Zenith Awards. The applicable categories are:

  • Water and Wastewater – IoT Monitoring Platform
  • Best Fieldbus Implementation – IoT Monitoring Platform
  • Power and Energy Management – IoT Monitoring Platform
  • Australian Industrial Product of the Year – IoT Monitoring Platform
  • IT Application of the Year – Telemetry Host IoT web platform
Endeavour Awards 2015 Finalists

Endeavour Awards 2015 Finalists

Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2015 Successful Endeavours Pty Ltd.

Victorian iAwards 2015

Last year at the Victorian iAwards 2014 , our client Rectifier Technologies Pacific took out 2 categories for Victoria. This year we are pleased to have 2 clients as finalists and at the iAwards ceremony this evening they both took out merit awards for their category. A merit award means they were judged to be within 5% of the category winners and so also qualify for inclusion in the National iAwards.

iAwards VIC Merit

iAwards VIC Merit

Sustainability

Rectifier Technologies Pacific received a Merit Award in the Sustainability category for the RT18 425V High Efficiency EV Charger Rectifier. This is an important technology breakthrough in high efficiency electric vehicle charging and we were pleased to see them received recognition for that. Software we developed for them is part of the product.

New Product

And Skynanny.net received a Merit Award in the New Product category. 

Skynanny.net iAward merit certificate

Skynanny.net iAward merit certificate – New Product

We are very pleased for Jason and Lynne who have had to persevere through a lot to get to this point. The combination of Bluetooth Smart, Qi Wireless Charging, 3G communications and GPS tracking in a device the surface area of a business card was a big technical challenge and deserved to be recognised.

Skynanny.net celebrate with Successful Endeavours and Zain Digital

Skynanny.net celebrate with Successful Endeavours and Zain Digital

Our congratulations also go to Zain Digital for their work in development of the App and Web Services that supports the product.

The list of winners and merit award recipients can be found at Victorian iAwards Winners 2015.

Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2015 Successful Endeavours Pty Ltd.

iAwards

The iAwards are an annual celebration of Innovation in driving economic growth in Victoria. This year we were pleased to see one of our clients, Rectifier Technologies Pacific, nominate for an award. They were encouraged to do so and I was pleased that they followed through on that encouragement.

iAwards

iAwards

iAwards Winners 2014

The iAwards 2014 Winners for Victoria have been announced and Rectifier Technologies Pacific are winners in 2 categories:

  • Research and Development
  • Sustainability

This was for their RT15 240V 100A HRE Rectifier. This is a high power level and high efficiency AC to DC Power Converter.

Rectifier Technologies Pacific

Rectifier Technologies Pacific

One of the reasons we are familiar with the product is that we did some of the core Embedded Software Development and know just how good the hardware design in the power stage is. You can get more information from Rectifier Technologies Pacific AC/DC Product Range.

So congratulations again to Rectifier Technologies Pacific and to all the rest of the winners at this year’s iAwards.

Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2014 Successful Endeavours Pty Ltd

What if we could start again

In the days when DC converters didn’t exist, it made sense to base our electrical distribution system on transformers and AC voltage level shifting. It still makes sense to distribute at high voltage where resistive losses in the wires are a smaller issue than they are at lower voltages. But if we were starting again, what would that look like?

The Grid From The Ground Up

A new approach to electricity distribution

A new formula for electrical distribution

IEEE Spectrum have published the results of discussion on just this topic and it caught my eye. We develop products for high voltage distribution including switch gear and power factor correction controllers so I also have personal knowledge of what goes into those. The full article is at The Grid From The Ground Up – What If We Could Do It Again?

A summary of the core issues we could resolve are covered below.

High Voltage Direct Current Transmission

Use High Voltage Direct Current, or HVDC, as the transmission standard. This is now possible whereas 100 years ago it was not. As much as anything this is a legacy issue. The electricity link between Tasmania and Victoria that runs under Bass Straight uses this technology for instance.

High Voltage Direct Current Distribution

HVDC Distribution

Renewables at any level

And we would design it to cope with any level of Renewable Energy sources. This is one of the inhibiting factors for the use of fluctuating energy sources and traditionally it was considered that 8% was the maximum you could have. Germany recently showed this wasn’t the case with a German Renewable Power Contribution of 59%. There is still plenty of work to do but this is an example that some of the old paradigms are not absolute limits after all.

Sources of Renewable Energy

Renewable Energy Sources

Resilience

Another issue is the robustness or Resilience of the grid. This refers to the ability of the grid to recover from transients and faults. The Northeast Blackout of 2003 showed that a lack of Resilience is a major weakness. If you aren’t familiar with the incident then check out the following short video on what happened and wider implications for not having Resilience.

 Regardless of the source of the issue, we have to be able to quickly isolate faults and not lose complete grid control. A Resilient grid is a must.

Communication

This is one of the things needed for Resilience. All generation and transmission facilities should be able to communicate so that the system can be coordinated. This is sometimes referred to as the Smart Grid and a lot of work has been done to create robust, widespread and secure communications to measure and control the operation of the Electricity Grid. One example is DNP3 which is widely used by Power Factor Correction Controllers, Reclosers, Sectionalisers, RTUs and control systems to monitor and manage the Electricity Grid. 

An example of a DNP3 enabled device is the ABB CQ900R Power Factor Correction Controller which for which we received the Industrial Electronics Future Award in 2011. 

ABB CQ900R Smart Controller

ABB CQ900R Smart Controller with DNP3

Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2014 Successful Endeavours Pty Ltd.

Solar Cells

The primary Solar Cell material is silicon. It converts photons into electricity and the more efficient panels have a multi-layered construction.

Silicon Solar Cell Construction

Silicon Solar Cell Construction

But it isn’t only the construction that affects the efficiency. There are other factors such as:

  • Angle of Incidence of the incoming light
  • Photon Density in the silicon
  • reflections
  • shading

These can make a significant difference to the outcome. In 2012 we received the Electronics News Future Award for The Environment. This was for our work in developing the control systems and sensors for a Tracking Solar Array. This has greater efficiency because it addressed all 4 of the above factors at the same time. Here is how it did that.

Angle of Incidence

The Angle of Incidence is also referred to as the Cosine Effect. As the light comes into the panel from a more acute angle, the effective area of the panel reduces and so the energy to be converted also reduces. So this means that Solar Cells produce more electricity when the sun is immediately overhead and the production falls of before and after that. So if the panel follows the sun during the day keeping the sun overhead or normal to the panel, then the amount of energy converted and electricity produced increases. But how much?

Solar Tracking Efficiency Improvement

Solar Tracking Efficiency Improvement

The graph above shows the improvement in Solar Photo-Voltaic Electricity Production due to tracking the sun for either the entire day, from 45 degrees either side of midday or from 30 degrees either side of midday. Even just tracking 30 degrees either side of midday gives you 40% more electricity whereas tracking 45 degrees either side of midday produces nearly 60% more electricity. This on its own is more that the current trends in materials and panel construction are predicted to be able to achieve.

It wasn’t that long ago that a panel would not produce, in its lifetime, enough energy to recover the manufacturing energy it took to make the panel.  The past 20 years have seen advances that now reverse this and a properly manufactured and installed Solar Panel is a net energy producer.

So where do the other efficiency improvements come from?

Photon Density

The Technique Solar Module used Fresnel lenses to concentrate the sunlight into strips of 1/4 cut Solar Cells. There were 10 such strips. As a result, the Photon Density went up by a factor of 3. This not only allow less silicon to be used for the same amount of light, but it also increases the energy conversion efficiency. So the Solar Cells were getting a conversion efficiency above 40%. This is double the normal efficiency of higher grade Solar Panels.

The reduction in shading comes from having a smaller structure which can be positioned to maximise access to open sky.

Reflections off the inside of the individual strips were actually used to direct sunlight back onto the Solar Cells. And the cells were high grade with the best anti-reflection surface layers.

And the array was split into 2 sections using a Micro-Inverter on each section. Micro-Inverters are a topic for another day but they will have a big role to play in the overall move toward renewable energy at the residential and commercial level.

Concentrated Solar Panel Array

Concentrated Solar Panel Array

The array above is a linear solar array. There is a Sun Position Sensor at the center of the linear array and the array it rotates about the central axis. This is a different approach to the work we did for Solar Systems (now part of Silex)which was a Concentrated Dish Array that did 2D tracking as shown below.

Solar Systems Dish On Sun At Fosterville

Solar Systems Dish on sun at Fosterville

What is clear is that Solar Cells and Solar Photo-Voltaic energy conversion are here to stay and will continue to grow in importance for creating energy with reduces pollution in the future. Regardless of the individual views on Global Warming and Climate Change, reducing pollution is always going to be in all of our long term interests.

Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2013 Successful Endeavours Pty Ltd.

Next Page »