The National Wind Technology Center features dynamometer research facilities that can validate power-take-off systems for wave and water power devices over a range of capacity ratings—from 1 kW to 5 MW.
Dynamometers can validate wave and water power-take-off (PTO) systems by replacing the power of the water with a controllable, electric motor. NREL's dynamometer research facilities can evaluate new PTO designs and assess a variety of components and subsystems—including generators, gearboxes, mechanical or electro-dynamic brakes, power electronics, control systems, and software. Manufacturers and design engineers can use our facilities to study PTO system performance and the integration of generators and power electronics with the electric grid, to perform accelerated lifetime certification, and to develop software.
Overall capabilities include the ability to:
- Perform steady-state evaluation to determine a PTO's power curve
- Conduct highly accelerated assessments in which the PTO is intentionally overloaded to determine its useful operating lifetime
- Operate in normal rotational or linear motion by using hydraulic actuators
- Operate in reciprocating (bidirectional) motion and provide or absorb power in either direction
- Apply secondary forces and moments other than the primary, driving torque or force
- Use "model-in-the-loop" techniques to emulate various system parameters with computer simulations that are operating in real time
- Connect to the controllable grid interface so that researchers can better understand how PTOs react to grid disturbances.
When evaluating PTOs, one size does not fit all. NREL has three dynamometers of varying sizes to offer flexibility to its partners.
The 225-kW dynamometer employs a 300-hp AC induction motore with a variable-frequency drive and AC grid connections of 120 V, 240 V, and 480 V.
The 2.5-MW dynamometer features a 3,351-hp, AC induction motor with a variable-frequency drive and 480 V, 690 V, and 13,200 V AC grid connections.
The 5-MW dynamometer features an 8,000-hp AC induction motor with variable-frequency drive and 480 V, 690 V, and 13,200 V AC grid connections.
See the National Wind Technology Center's dynamometer fact sheet for more details about each dynamometer.