Start up takes power switching technology out of university lab

Technology does make it out of the lab, but sometimes it takes a while. A case in point is the work undertaken by Cambridge University researcher Dr Patrick Palmer. He's been looking at igbts for the last 15 years and his principal research interest is the design, characterisation and use of power semiconductor devices, including the use of high voltage igbts connected in series, the characterisation of igbts and the computer simulation and optimisation of igbts and diodes. He had been talking with companies over the years, but couldn't commercialise the work. But a conversation with Pete Magowan – one of ARM's earliest employees – changed that. Magowan saw wider application for Dr Palmer's research and started exploring the technical issues. The research is now being commercialised by a start up called Amantys – Magowan is the company's chairman – which has recently received $7million in Series A funding from Moonray Investors. Amantys' technical director, Mark Snook, said that, while Dr Palmer's work was generating interest, it was taking too long to develop. "Because the Amantys founders haven't come from a power engineering background, we spent some time thinking about where the opportunities would be for the technology. We applied the 'so what?' test; you might have great technology, but it's no good if you can't do anything with it." Richard Ord, marketing director, expanded. "Amantys is a small team with a mix of skills. Alongside people with digital and SoC design experience, we have power, analogue and mechanical engineers. This mix of different skills and perspectives is unusual for a Cambridge based start up." Amantys was established at the end of 2009 and received some seed funding. But, as chief executive Bryn Parry recalled, the financial crisis was in full flow. "There wasn't a lot of early stage money out there, but our advantage was that what we were doing wasn't dependent on silicon." Snook said the management team had a lot of calls with potential backers. "We had interesting discussions," he noted, "but they couldn't make the link between our technology and a product. It was clear to us that Moonray had done its 'due diligence'. It had asked itself questions like 'is the market big enough?', 'what is Amantys doing which is different?' and 'has it got the right people?'." Amantys is looking to improve the efficiency and reliability of power switching. And it's a big market to address. According to a market researcher, the global market for igbt based power modules in 2010 was $3billion and this is expected to grow to $5.4bn by 2015. Conversion efficiency is one of the major drivers for the sector. But the company says this needs a new approach, with tight control at the core of the system and the ability to provide remote control and monitoring. Its architecture integrates these elements into an intelligent power switch, with applications in such sectors as renewable energy generation, data centre power supplies and hybrid and electric vehicles. Parry explained the approach. "There are a range of challenges, including reducing losses, better reliability and cost reduction. In order to address these, we believed it was time for a new approach and that the way in which power electronics are designed needed to be redefined." Ord said: "Switching is on or off and if you can control that switching so you don't get voltage overshoot, you don't need to overspecify the igbt and you don't get ringing. We've looked at how our technology impacts a system and we believe we can reduce switching losses by up to 50%." Developing technology is one thing; getting a positive market reception is another. Parry said that while people 'got it', they were sceptical about something which could switch so quickly. Snook gave more insight: "Every customer said 'very interesting', but our problem was how to engage with them; they all asked whether we had something they could buy." Ord encapsulated the challenge: "If you can't explain your technology to a customer, you haven't understood it and what you're trying to achieve." Power electronics technology is in demand from companies like ABB. Parry said: "These are all large companies which are not used to dealing with start ups." While that was a challenge, it also provided opportunities, as Snook recalled. "Being a power electronics start up was useful in getting meetings with these companies, but the problem was meeting with the right people." The reason, Parry said, was due to the power electronics industry being conservative industry with few start ups. "This threw up barriers and made deals quite difficult," he said. A solution was the 'flight case' demonstrator. "This allowed us to show our technology in front of companies' technical people," said Snook. "But it was still seen as university work, so we developed the Amantys PCB, which brought new functionality." Even this was a challenge. "We're looking to switch 1kV at 100A," said Snook. "How do you make a demo of that technology without making it possible for someone to kill themselves. And even if you can, what could they do with it?" Having got through the initial phase, Amantys is now building for the future. "We've spent more time developing the tram alongside the technology," said Snook. "We now have an operations manager to create a supply chain and we're getting access to the right consultants. But our biggest challenge is knowing how many other people we have to add to the team." Amantys' first product is the Power Drive, a high isolation gate drive for medium and high voltage applications. The single channel gate drive incorporates system enhancements, which the company says deliver better reliability and improved performance over existing solutions. Parry continued: "It's intelligent power switching, with the intelligence integrated into a standard digital interface. It's also programmable – users can control dV/dt and dI/dt – so the switching characteristics can be changed on the fly. And, as it's independent of material technology, it could be integrated in a SiC mosfet, for example." The design sits within the footprint of a power module, creating a smaller, more robust product. The 3.3kV Amantys Power Drive, available in 1200A and 1500A ratings, works with igbt modules from different manufacturers without gate resistor changes. Suitable for use with two, three and multilevel converters in a variety of applications, the device can switch modules from Dynex, Infineon, Mitsubishi and Toshiba. The ability to program the Power Drive may free designers to be more creative, at least in Snook's opinion. "Power engineers are currently doing discrete designs, so they do a lot of repetitive work. Power Drive may well allow them to do things which differentiate their products," he concluded.