Synchronous condenser

Parallel connected synchronous condensers are mainly used for providing short-circuit power and inertia. They also help to stabilize the network through voltage recovery during faults. This becomes increasingly important with the rising share of renewable power generation that leads to a lack of short-circuit power and inertia.

Due to the fact that conventional power plants are shut down, synchronous condenser solutions use a conventional generator to provide the necessary inertia and short-circuit contribution by means of its rotating mass while also providing or absorbing reactive power. 

A synchronous condenser provides short-circuit power, inertia, and reactive power for dynamic loads. Siemens Energy supplies a broad range of generators up to 1,300 MVA at full speed.

Our synchronous condenser solutions utilize a generator to provide the necessary inertia with its rotating mass while also offering or absorbing reactive power. The generator is connected to the transmission network via a transformer and is started by either an electric motor or a static frequency converter. Once operating speed is achieved, the generator synchronizes with the network, functioning like a synchronous motor with no load, thereby supplying reactive power and short-circuit power to the transmission network.

See the synchronous condenser diagram below, which illustrates the key components and operational principles of our solutions. It highlights how the generator, connected to the transmission network, provides essential inertia and reactive power. The diagram also emphasizes the role of the electric motor or static frequency converter in starting the system and the synchronization process with the network. This visual representation enhances the understanding of how synchronous condensers improve grid stability and facilitate the integration of renewable energy sources.

To provide maximum inertia, Siemens Energy has extended the established synchronous condensers solution with additional rotating mass from a flywheel. This extension is a very effective method to maintain the required level of inertia and thus the RoCoF (Rate of change of frequency) of the system. Rotating mass provides an inherent synchronous inertia response (SIR), what is counteracting grid frequency fluctuations with active power injection or absorption during sudden load unbalance events.

One of our current projects - Rassau: turnkey solution synchronous condenser with Flywheel

• Short-circuit power guarantees a reliable system operation and system strength
• 1100 MWs kinetic energy with the operating range of ±60 Mvar at 132 kV
• Inertia reduces oscillation on grid frequency and prevents system blackouts

Synchronous condensers help to drive the decarbonization journey for power assets. With the rising adoption of renewable energy, traditional power generation methods are utilized less, and generators are being shut down. A Brownfield rotating grid stabilizer conversion not only enables a rising share of renewable infeed on the grid but also provides a significantly reduced carbon footprint compared to a new build.

As a leading manufacturer of synchronous condensers, we are committed to delivering innovative solutions that enhance grid stability and efficiency. Our expertise in advanced engineering and technology allows us to design and produce high-quality synchronous condensers tailored to meet the specific needs of power systems worldwide. With a focus on reliability and performance, we support the transition to renewable energy by providing essential reactive power and inertia, ensuring a robust and resilient electrical grid for the future.