Developing revolutionary technology that could defend the UK's National Power Grid against blackouts
A revolutionary HVDC technology developed at the University of Birmingham could defend the UK's National Power Grid against system blackouts.
First he had the ‘lightbulb moment’; then he showed how it could stay switched on. Now Professor Xiao-Ping Zhang has demonstrated the technology is available to create a ‘power and energy internet’ (PEI) to transform the world’s energy use and management by the exchange of power sources across regions, countries and even continents.
In fact, this electrical power superhighway is already starting to happen: the UK now has high-voltage, direct-current (HVDC) transmission links with several neighbouring countries, including France, Ireland, Holland and Norway, with more in the pipeline. ‘These are either in operation already or being constructed,’ says Xiao-Ping, Professor of Electrical Power Systems and Smart Grid Director of the Birmingham Energy Institute.
This is the result of a European Commission strategy – based on a concept proposed four years ago by Xiao-Ping and his research group – to establish a European Energy Union.
The establishment of a worldwide PEI would mean power grids across the globe would be linked, leading to a shared focus in meeting energy challenges, which in turn would almost certainly lead to cheaper electricity, renewable energy becoming the main power sources and a significant drop in CO2 emissions.
Even more remarkably, Birmingham and the West Midlands would be at the centre of this global energy revolution. ‘If you look at the future of PEI, the UK is going to be the global as well as the European hub, because we have a lot of renewable energy resources here – tidal, wave and wind – and the West Midlands is the energy hub of the UK already,’ says Xiao-Ping.
This will be the message at an event hosted by the University on February 15 to promote ‘Energy Capital’, which aims to unite all major stakeholders in energy technologies and systems in the region, and to put the West Midlands as the UK’s focal point for future energy innovation and investment.
The event, to be attended by leaders from industry, politics and academia, will include a Distinguished Lecture by Professor Sir David King, the Foreign Secretary’s Special Representative for Climate Change.
Another clear indicator that Xiao-Ping’s vision is on the verge of becoming a plugged-in reality is his most recently published paper, which demonstrates the technology is in place to prevent global power outage.
Entitled ‘Elimination of Communication Failures of LCC (line-commuted convertor) HVDC system with Controllable Capacitors’, the article won the College’s Paper of the Month award (the second such Xiao-Ping has won the award). Co-written with Birmingham colleagues Ying Xue and Conghuan Yang, it was published by IEEE Transactions on Power Systems. Such is the interest in PEI that the article was one of the online publication’s most-downloaded papers. ‘People are recognising the importance of it, which puts us in a leading position,’ says Xiao-Ping.
‘The big challenge we have is that this system is vulnerable to faults. Imagine we had a fault in the UK with the DC links. It would mean neighbouring DC links would be affected, and if that happened it could trigger a system-wide blackout. The DC system would be shut down.’
The paper outlines an innovative solution – a ‘push’ and ‘pull’ method using dynamic capacitor insertion – to what would otherwise be a serious stumbling block to PEI.
‘Our solution is not only innovative; it ensures that the system is always operational. In other words, it would never have to be shut down.’
Existing solutions, he explains, can reduce the impact on the system, but not eliminate it. ‘It works in some situations, but not in others. Our approach is fundamentally different and solves the problem completely. It works whatever the situation, keeping the HVDCs operational and bringing the system back to normal very quickly, and will always avoid having to shut down the system.’
The method proposed in the paper involves converting DC power into AC (alternating current) power, which ‘increases the effective commutation voltage and enables successful commutation even in the absence of AC commutation voltage during the fault conditions, i.e. zero impedance three-phase grounding fault’.
Naturally modest, Xiao-Ping is quietly excited that his vision is now much more than a pioneering idea.
‘This is not only a high-level vision; we have now proved with this paper that we have the technology to make it happen and make it work,’ he explains. ‘What is more, we have the confidence. What we need to do now is to tell people what we have done so far – and what can be done in the future. That is why the Energy Capital event is so important.’