Variable speed distributed drive train wind turbine system

A fluid-flow turbine comprising:

• a blade for converting fluid-flow power into mechanical power;
• one or more sensors, an output thereof being sensor information;
• a plurality of synchronous generators selected from the group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators, said synchronous generators being operatively connected to said blade for converting said mechanical power into fixed-frequency utility-connected AC electrical power;
• a plurality of rectifiers electrically connected to each of said synchronous generators for converting said AC electrical power of each synchronous aenerator into DC electrical power;
• a plurality of active inverters electrically connected to each of said plurality of rectifiers to convert said DC electrical power of each of said plurality of rectifiers into AC electrical power, each active inverter capable of regulating DC electrical current;
• and,
• a control unit connected to said one or more sensors and to said active inverters, said control unit capable of causing each of said active inverters to regulate said DC current of said active inverters in accordance with said sensor information.

A fluid-flow farm comprising:

• a plurality of fluid-flow turbines each of which includes a synchronous generator coupled to a rectifier and an inverter, an output of said inverter being connected to a transformer, wherein reactive power control is fixed at said output of said inverter so that power factor is unity or set to provide a leading power factor that compensates for VAR of said transformer;
• an electrical collection system electrically connected to each of said fluid-flow turbines, said electrical collection system having an output, which is an aggregate output of said fluid-flow farm, said output being connected to a substations wherein said electrical collection system is sized for operation of said fluid-flow turbines at unity power factor;
• and,
• a dynamically adjustable power factor controller at said substation for adjusting the power factor of said aggregate output of said fluid-flow farm.

A fluid-flow farm comprising:

• a plurality of fluid-flow turbines each of which includes one or more synchronous generators, each coupled to a rectifier and an inverter, an output of said inverter being connected to a transformer, wherein VAR control is fixed at said output of said inverter such that a VAR load is set between and a leading power factor to compensate for the VAR of said external transformer and unity power factor, inclusive;
• each one of said fluid-flow turbines comprising a blade which converts fluid-flow power into mechanical power, said one or more synchronous generators being selected from a group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators, said synchronous generators being operatively connected to said blade;
• an electrical collection system electrically connected to each of said fluid-flow turbines and to a substation, wherein said electrical collection system is sized for operation of said fluid-flow turbines at unity power factor;
• and,
• a dynamically adjustable power factor controller at said substation for adjusting the power factor of the aggregate output of said fluid-flow farm.

An apparatus for generating electric power comprising:

• first means for converting fluid-flow power into rotational mechanical power;
• sensor means for providing sensor information;
• a plurality of synchronous generators selected from a group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators, said synchronous generator being connected to said first means for converting said mechanical power into AC electrical power;
• rectifying means connected to said plurality of generators for rectifying outputs of said generators to thereby convert said AC electrical power of said generators into DC electrical power;
• inverting means connected to said rectifying means for inverting said DC electrical power to thereby convert said DC electrical power to AC electrical power said inverting means being capable of regulating DC electrical current;
• and,
• control means connected to said sensing means and to said inverting means, for causing said inverting means to regulate said DC electrical current in accordance with variations in said sensor information.

An apparatus for generating electric power comprising:

• a transformer:
• a plurality of fluid-flow turbines, each of which includes a synchronous generator coupled to a rectifier and an inverter, an output of said inverter being connected to said transformer, wherein reactive power control is fixed at said output of said inverter so that power factor is unity or set to provide a leading power factor that compensates for VAR of said transformer;
• a substation;
• an electrical collection system electrically connecting each of said fluid-flow turbines to said substation;
• said electrical collection system being sized for operation of said fluid-flow turbines at unity power factor;
• and
• means at said substation for dynamically adjusting the power factor of the aggregate output of said plurality of fluid-flow turbines.

A apparatus for generating electric power comprising:

• a plurality of fluid-flow turbines, each of which utilizing a blade to drive synchronous generators selected from a group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators, said synchronous generators converting fluid-flow power into AC electrical power at unity power factor;
• converting means associated with each turbine for converting said AC electrical power of said synchronous generators into DC electrical power;
• means for inverting said DC electrical power of each said synchronous generators of a turbine to thereby convert said DC electrical power to AC electrical power;
• an electrical collection system for electrically connecting each of said fluid-flow turbines to a substation wherein said electrical collection system is sized for operation of said fluid-flow turbines at unity power factor;
• and,
• means for dynamically adjusting the power factor of the aggregate output of said plurality of fluid-flow turbines at said substation.

A method of generating electric power comprising steps of:

• A. converting fluid-flow power into mechanical power;
• B. providing sensor information;
• C. utilizing a plurality of generators selected from a group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators to convert said mechanical power into AC electrical power;
• D. rectifying outputs of said generators to thereby convert said AC electrical power of said generators into DC electrical power;
• E. inverting said DC electrical power at an inverter to thereby convert said DC electrical power to AC electrical power;
• and,
• F. regulating DC electrical current at said inverter in accordance with variations in said sensor information.

A method of generating electric power comprising steps of:

• A. providing a plurality of fluid-flow turbines that include synchronous generators selected from a group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators, said generators converting fluid-flow power into AC electrical power at a power factor fixed between a leading power factor to compensate for the VAR of an external transformer and a unity power factor, inclusive;
• B. electrically connecting each of said fluid-flow turbines via an electrical collection system to a substation wherein said electrical collection system is sized for operation of said fluid-flow turbines at unity power factor;
• and
• C. dynamically adjusting the power factor of the aggregate output of said plurality of fluid-flow turbines at said substation.

A method of generating electric power comprising steps of:

• A. providing a plurality of fluid-flow turbines, each of which utilizing a blade to drive synchronous generators selected from a group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators, said generators converting fluid-flow power into AC electrical power at unity power factor;
• B. rectifying outputs of each said synchronous generators of a turbine to thereby convert said AC electrical power of said synchronous generators into DC electrical power;
• C. inverting said DC electrical power of each said synchronous generators of a turbine to thereby convert said DC electrical power to AC electrical power;
• D. electrically connecting each of said fluid-flow turbines via an electrical collection system to a substation wherein said electrical collection system is sized for operation of said fluid-flow turbines at unity power factor;
• and,
• E. dynamically adjusting the power factor of the aggregate output of said plurality of fluid-flow turbines at said substation.

A variable speed wind turbine comprising:

• a turbine rotor including at least one blade mounted on a rotatable shaft;
• a synchronous generator selected from the group consisting of wound field synchronous generators wherein an exciter field is excited with a constant current and permanent magnet synchronous generators,
• said synchronous generator being coupled to said turbine shaft for rotation therewith;
• a sensor, an output of which is sensor information;
• a power converter including an active inverter having switches that can be activated in response to inverter current commands in such a way as to vary DC current for phases of said generator;
• and,
• a controller coupled to said sensor and to said inverter, an output of said controller being an inverter current command related to required generator torque.