In essence, a Dumarey Flybrid system allows us to reduce the size of the generator (and therefore fuel) whilst powering a tower crane. Dynamic duty cycles, similar to what you see on a tower crane, waste a great deal of energy because they require a lot of power for short periods of time. As a result, this type of application has traditionally required oversized power trains purely to cope with the peak demand. However, what if a power source, such as a generator or mains supply, could draw on an external power source, to deliver that peak dynamic load, injecting only when the large power demand is required e.g. when a crane lifts a heavy load at maximum speed. A short surge of power from an outside source when needed would allow the size of the generator powering the tower crane to be matched to the average load, and therefore reduced – when slewing or lifting lighter loads – thus saving fuel and reducing emissions. This is exactly what the Dumarey Flybrid does.
The Dumarey Flybrid system uses flywheel energy storage system, essentially a highly engineered flywheel which can spin at high speeds, connected to a combined electric motor/generator which powers the flywheel during periods of lower demand and then converts to a generator driven by the flywheel when the crane needs more power. This running gear is then enclosed in a protected ventilated, skid mounted generator like case measuring 1.2m x 1.6m x 1.5m and weighing approximately 500kgs. This is then plugged into a power source (a diesel generator for example), and then to the tower crane.
Inside the Flybrid the energy is stored as kinetic energy in the spinning flywheel, and this is transferred by the motor/generator to the crane when it needs a short burst of power. When the tower crane is about to lift a load and spike the power requirement, the Flybrid system reacts to the frequency and voltage changes between the power source and application and uses the energy stored in the flywheel to generate the extra power to cover the crane’s surge requirement, eliminating the additional demand on the generator. This allows the generator to run at almost constant load, rather than forever changing to cope with the differing power requirements of a tower crane.
