While running a motor backwards isn’t usually the first idea that comes to mind, it could be an efficient way to power a pumped hydro site.
Generally, running any mechanical equipment backwards isn’t recommended. In most cases the process is unproductive and inefficient – if not completely dangerous.
But when undertaken in the correct manner it can deliver productive results. This is exactly what Toshiba engineers are doing on a current pumped hydro project.
For projects like this one, motors drive pumps that push water where it needs to go. But when the situation is reversed, and the pumps are instead used to drive the motors, something extraordinary happens – the motors run in the opposite direction and become generators that produce electricity.
Typically, pumped hydro power plants have long generator maintenance periods that span several months, and the plant’s large equipment remains idle throughout that period.
It’s not an ideal situation, and the economics of keeping these large-value assets idle for long periods is always a concern for the plant’s management team.
Rather than let the equipment sit idle, the dam water’s gravity could be used to turn the pumps and make them the prime movers for the connected motors. These motors now become generators, producing electricity to power the site.
However, it’s not as easy as simply reversing the motors. This type of arrangement requires precise speed control to operate motors at the optimum point and ensure exact synchronisation of voltage, current and frequency.
This is where Toshiba’s engineers have an advantage: the Toshiba regenerative MV drive is equipped with features that allows it to do exactly that.
Toshiba MV drives have been controlling motors in Australia and elsewhere in the world for decades. These drives are available up to 120MVA up to 7kV with smaller capacities at 11kV rating, and include features like extensive motor protection, that allow for more precise utilisation. They’re designed to work in tandem with Toshiba HV motors, but their flexibility and adaptability means they can be used with almost any motor brand.
Utilising the backwards drive of a HV motor isn’t an idea that immediately comes to mind when looking for solutions to power a site. But comprehensive solutions are what Toshiba is known for.
Toshiba’s highly qualified team of engineers and technicians undertake complex engineering designs and simulations, and test and commission the entire system to ensure that it meets customer’s specifications and produces desired result. It’s this complete service package – from the feasibility studies through to the commissioning of the project – that is highly valued by customers.
Toshiba has developed a reputation for delivering solutions to complex HV motor and drive problems – and sometimes that solution is as simple as looking at a piece of equipment and seeing if it can be driven differently.
For more information, visit tic.toshiba.com.au
Featured image: Toshiba.
