Renewable power is transforming energy networks around the world, and ABB’s work in the Northern Territory shows how synchronous condensers can provide system strength and contribute to the energy transition.
Life in the Northern Territory isn’t like that in the southern states. It’s blazing hot, brilliantly sunny and sparsely populated – factors that affect people, but less obviously also shape power generation.
That low density means the Territory’s power networks are isolated around population centres such as Darwin and Alice Springs, and its remoteness means those networks are not linked to the rest of Australia.
Meanwhile, all that sun provides immense amounts of solar energy – sometimes even more than the networks can handle.
“During the peak dry season, they were generating more power than they needed, and the demand for their traditional generators was reduced to the point where it wasn’t feasible to keep them operating,” said Rory Paltridge, Head of Motion at ABB Australia.
“Because of the big increase in solar power, they wanted to start shutting the generators off during peak periods, but a conventional generator needs to have a certain amount of output just to prevent mechanical damage.”
Solar farms use an inverter-based resource (IBR) technology to connect to the grid. However, IBRs cannot provide the physical inertia that a conventional turbine can. Once they’ve been incorporated, turning off the network’s generators would make the grid vulnerable to potential network frequency fluctuations. In that situation, the best solution for improving grid strength and stability is a synchronous condenser.
Synchronous condensers are electrical machines consisting of a rotating mass that is not driven by an engine or turbine. The synchronous condenser helps to resist changes to the network and adjust fluctuating conditions in the electrical grid.
“During periods of excess generation or light load conditions, synchronous condensers dynamically absorb or supply reactive power to regulate system voltage, while also contributing short-circuit current and rotational inertia to support the overall grid stability,” said ABB application engineer Deepa Sasikumar.
When the grid voltage is too low, the SynCon operates in an over-excited mode to supply reactive power and thus boost the voltage. Conversely, when the grid voltage is too high, the SynCon operates in an under-excited mode to absorb reactive power from the grid and reduce the voltage rise.
It’s a solution that applies to a range of sustainable energy types, such as wind, solar and more, Sasikumar said. And as the world increases its demand for renewable energy, so too will the demand for synchronous condensers go up.
“As developers install more renewables into the system and traditional coal power stations are being de-commissioned, synchronous condensers will be required to protect the grid,” she said.
“The world is needing more and more renewables, and because solar and wind are inverter-based resources, integrating a synchronous condenser into the system provides grid stability and strength.”
Proof of work
The Northern Territory is a unique environment, and ABB’s experts speak from the experience of having seen and solved similar situations before. Synchronous condensers are a long-established method of integrating renewable energy into electrical networks.
“Overseas, we’ve been supplying synchronous condensers since the 1960s,” Paltridge said. “We’ve been supplying them into the Australian market since 2010, but we’ve also got a long track record of supplying generators and other large machines here. It’s a purpose-built product and a very proven solution.”
But because the Northern Territory’s grid is smaller and more isolated than the rest of Australia’s power networks, ABB’s solution there needed to be locally sustainable.
“The Northern Territory doesn’t have the network transmission infrastructure to draw strength from the South West Interconnected System or the eastern coast’s networks,” Paltridge said.
“In the east-coast energy market, they can shift strength to a certain extent. They can’t do it as much as they need to – Queensland can’t draw from South Australia, for example – but the Northern Territory has to have an entirely localised solution.”
The ABB offering is what it calls a “complete electrical balance of plant”: the synchronous condenser, along with associated equipment that helps to get the maximum output from the solution.
This includes cooling and lubrication systems, as well as a long-term service agreement to maintain the equipment over a 12-year cycle. The synchronous condenser itself is expected to last more than 25 years, and some installed by ABB in the 1960s are still operating today.
Ready to go
While the typical lead time for a solution like this would be three years, ABB is able to deliver its modular solution and have it running within two years of receiving an order. That speed made ABB particularly attractive to the Northern Territory project requirements, which needed a rapid solution for its energy network issues.
“That lead time is one of our strengths,” said Paltridge. “Most of our competitors make very bespoke synchronous condensers that typically require a long lead time, whereas we have a much more productised solution, giving us market-leading delivery schedules.”
ABB also offers local support and aftersales service via a local service team, and its shorter lead time adds to its competitive advantage and provides value to its customers.
The company’s Motion Large Machines factory is located in Sweden and has been operating since 1890 – evidence of the rich experience that ABB has with this technology. Being made in Sweden ensures that ABB’s synchronous condensers are not only a premium quality product that is customised to the particular needs of each project; they are also an environmentally sustainable one.
“The factory in Sweden is 100 per cent powered by renewable energy and has zero waste-to-landfill,” Paltridge said. “And these synchronous condensers are more than 95 per cent recyclable.”
Visit the ABB website to learn more about why ABB’s synchronous condensers are the best solution for grid strength and stability.
Motor generators are good for smoothing load changes and supplying instant response to demand. However, if the grid suffers a cascade failure than you see the difference from spinning reserve in a base load generator. You will need to make other arrangements to restart the grid and reconnect services. It is better to consider them just for large load change smoothing.
John