Multi-rotor turbine arranged for coordinated rotational speeds

A method of controlling a wind turbine system comprising a plurality of wind turbine modules mounted to a support structure including a tower, each of the plurality of wind turbine modules including a rotor, wherein, in use, each rotor has an associated rotating unbalance that defines an unbalance vector;

• the method comprising:
• coordinating the rotational speeds of the plurality of rotors to attenuate oscillations of the support structure caused by the rotating unbalance of the rotors.

A controller for a wind turbine system comprising a plurality of wind turbine modules mounted to a support structure including a tower, each of the plurality of wind turbine modules including a rotor, wherein, in use, each rotor has an associated rotating unbalance that defines an unbalance vector, wherein the controller comprises a processor, a memory module, and an input/output system, and wherein the memory includes a set of program code instructions which when executed by the processor, perform an operation comprising:

• coordinating the rotational speeds of each of the rotors to attenuate oscillations of the respective support structure caused by the rotating unbalance of the rotors.

A computer program product downloadable from a communication network and/or stored on a machine readable medium, comprising program code instructions which, when executed by one or more processors, perform an operation for controlling a plurality of rotors mounted to a support structure including a tower, each rotor having an associated rotating unbalance that defines an unbalance vector, the operation comprising:

• coordinating the rotational speeds of each of the rotors to attenuate oscillations of the respective support structure caused by the rotating unbalance of the rotors.