SCC: Project successfully completed
VEM transresch: New subsynchronous converter cascade (SCC) installed at Berlin water works
A project to install a new SCC has come to a successful conclusion with acceptance testing for VEM transresch. The clean-water pump 7 upgrade at Tiefwerder water works plays a part in ensuring an unrestricted supply of drinking water.
VEM transresch took part in a public tender competing against competitors and alternative engineering solutions for the subsynchronous converter cascade (SCC) project. The project was completed during running operation at the Berliner Wasserbetriebe water supply company’s Tiefwerder water works.
The water company commissioned the IfE Grothe GmbH engineering firm for planning and construction management. “The SCC gave us the best solution in terms of engineering and economics as we could continue to use the existing drive motor and minimise the energy losses from the system as a whole,” said IfE CEO Karsten Borchowitz, describing the benefits of the transresch solution. “Apart from that, the SCC has been designed for the expected speed setting range for the clean-water pump, so it didn’t need to be dimensioned for the full rated pump output. And not least, the SCC supports slip power recovery back into the grid – a power and cost-saving solution.”
The Tiefwerder water works has been playing a part in supplying six Berlin districts with drinking water since 1914.
What is an SCC?
A subsynchronous converter cascade is a cascaded connection of uncontrolled and controlled power converters inside the rotor circuit of a multiphase asynchronous slip-ring motor, and feeds slip power back into the grid. This system can be used in any industrial discipline, and is especially used where the existing multiphase asynchronous slip-ring motor needs to be preserved or a DC motor is not an option due to commutator maintenance, and a limited speed setting range is sufficient as is the case in applications such as centrifugal compressor, blower, and rotary pump drives.