Fuzzy logic integrated electrical control to improve variable speed wind turbine efficiency and performance

Claim 2

An efficient wind turbine driven electric power generator fuzzy logic based control system to improve power efficiency of the generator comprising: an induction operated generator including an air gap with magnetic flux; a pulse width modulated control to vary an operating speed of said generator to maintain a substantially constant power frequency output from said generator; fuzzy logic based controls to modify the operation of said pulse width modulated control to maximize the power output of said generator under variations of a wind driving said power generator; the modification of said operation of said pulse width modulated control to maximize said power output including means to vary said airgap magnetic flux of said generator; said generator being a squirrel cage induction generator; and said pulse width modulated control including solid state insulated gate bipolar transistor power electronic rectifier-inverter combination enabling power to flow in either direction to enable said generator to operate as a motor to provide start-up torque for said wind turbine generator.

Claim 3

The wind driven fuzzy logic based control system of claim 1 wherein said fuzzy logic control system further includes a fuzzy logic adaptive controller to adjust the speed of a variable speed generator for maximization of power output; said adaptive controller operating on feedback signals derived from the electric power output of said electric power generator without the need for any wind velocity data.

Claim 4

The improved wind driven fuzzy logic based control system of claim 2 wherein said fuzzy logic control system includes at least one fuzzy logic controller which controls a flux component of current of said generator to control said air gap magnetic flux to reduce a power losses of said generator to further maximize the power output of said generator.

Claim 5

An efficient wind driven turbine driven electric power generator fuzzy logic based control system to improve power efficiency of the generator comprising: an induction operated generator including an air gap with magnetic flux; a pulse width modulated control operating to vary a speed of said generator to maintain a substantially constant power frequency output from said generator; fuzzy logic based controls to modify the operation of said pulse width modulated control to maximize a power output of said generator under variations of a wind driving said power generator; the modification of said operation of said pulse width modulated control to maximize said power output including means to vary said airgap magnetic flux of said generator; wherein said control system further includes at least one solid state converter to control the speed of said generator to maintain said substantially constant power frequency; said fuzzy logic control system further includes a fuzzy logic adaptive controller to adjust the speed of said variable speed generator for maximization of power output; said fuzzy logic control system includes at least one fuzzy logic controller which controls a flux component of current of said generator to further maximize the power output of said generator; said at least one solid converter includes a pulse width modulator and said fuzzy logic control system provides an input to said pulse width modulator; and wherein said fuzzy logic controller utilizes a fuzzy logic role base which is substantially: ______________________________________ ΔP.sub.o \LΔ N P ______________________________________ PB NB PB PM NM PM PS NS PS ZE ZE ZE NS PS NS NM PM NM NB PB NB ______________________________________ wherein: P o =power output of generator L.sub.Δ =last change S=small B=big N=negative P=positive Z=zero.

Claim 6

An efficient wind driven turbine driven electric power generator fuzzy logic based control system to improve power efficiency of the generator comprising: an induction operated generator including an air gap with magnetic flux; a pulse width modulated control operating to vary a speed of said generator to maintain a substantially constant power frequency output from said generator; fuzzy logic based controls to modify the operation of said pulse width modulated control to maximize a power output of said generator under variations of a wind driving said power generator; the modification of said operation of said pulse width modulated control to maximize said power output including means to vary said airgap magnetic flux of said generator; wherein said control system further includes at least one solid state converter to control the speed of said generator to maintain said substantially constant power frequency; said fuzzy logic control system further includes a fuzzy logic adaptive controller to adjust the speed of said variable speed generator for maximization of power output; said fuzzy logic control system includes at least one fuzzy logic controller which controls a flux component of current of said generator to further maximize the power output of said generator; said at least one solid converter includes a pulse width modulator and said fuzzy logic control system provides an input to said pulse width modulator; and wherein said fuzzy logic controller utilizes a fuzzy logic role base which is substantially: ______________________________________ ΔP.sub.o \LΔ N P ______________________________________ PB NB PB PM NM PM PS NS PS ZE ZE ZE NS PS NS NM PM NM NB PB NB ______________________________________ wherein: P o =power output of generator L.sub.Δ =last change S=small B=big N=negative P=positive Z=zero.

Claim 7

The wind driven fuzzy logic control system of claim 4 wherein said generator is an induction generator which also operates as an induction motor when supplied with input power to provide starting torque to initiate rotation of said wind turbine.

Claim 8

An efficient integrated intelligent adaptive controller for a variable speed electric power generator including an air gap with magnetic flux driven by a variable power source comprising: said generator being a squirrel cage induction motor; power detection means to detect an electrical output power of said electrical power generator; means including fuzzy logic control means to maintain a required speed of said electrical power generator for substantially constant power frequency output substantially independent of wind turbulence effects; means to determine an optimum operation of said electrical power generator which will provide improved efficiency; and said fuzzy logic control means to vary said airgap magnetic flux of said electrical power generator in increments to modify said speed of said generator to further improve said efficiency; said fuzzy logic control including a plurality of intelligent fuzzy logic controllers operating in response to signals derived from the power output of said electric power generator; said fuzzy logic controllers providing a plurality of control signals; one of said control signals varying a rotor speed of said generator to optimize a turbine aerodynamic efficiency for maximum power output; and another of said control signals reducing a magnetizing component of a stator current of said generator to optimize said generator air gap magnetic flux to minimize power losses of said generator.

Claim 9

An efficient integrated intelligent adaptive controller for a variable speed electric power generator including an air gap with magnetic flux driven by a variable power source comprising: said generator being a squirrel cage induction motor; power detection means to detect an electrical output power of said electrical power generator; means including fuzzy logic control means to maintain a required speed of said electrical power generator for substantially constant power frequency output substantially independent of wind turbulence effects; means to determine an optimum operation of said electrical power generator which will provide improved efficiency; and said fuzzy logic control means to vary said airgap magnetic flux of said electrical power generator in increments to modify said speed of said generator to further improve said efficiency; said fuzzy logic control including a plurality of intelligent fuzzy logic controllers operating in response to signals derived from the power output of said electric power generator; said fuzzy logic controllers providing a plurality of control signals; one of said control signals varying a rotor speed of said generator to optimize a turbine aerodynamic efficiency for maximum power output; and another of said control signals reducing a magnetizing component of a stator current of said generator to optimize said generator air gap magnetic flux to minimize power losses of said generator.

Claim 10

The improved integrated fuzzy logic control of claim 6 wherein said variable power Source is wind and a wind turbine is provided to rotate said generator in response to said wind.

Claim 11

The integrated fuzzy logic control of claim 7 wherein said at least one fuzzy logic controller utilizes a rule base which is substantially: ______________________________________ ΔP.sub.o \LΔ N P ______________________________________ PB NB PB PM NM PM PS NS PS ZE ZE ZE NS PS NS NM PM NM NB PB NB ______________________________________ Wherein: P 0 =power output of generator LΔ=last change S=small M=medium B=big N=negative P=positive Z=zero.

Claim 12

The integrated fuzzy logic control of claim 8 wherein said generator is an induction generator which can also operate as an induction motor when supplied with input power to provide starting torque to initiate rotation of said round turbine.

Claim 13

The integrated fuzzy logic control of claim 9 wherein the output of said generator is connected to a power grid, and said input power is provided by said power grid when said induction generator operates as an induction motor.

Claim 14

An efficient integrated intelligent controller for a variable speed generator including an air gap with magnetic flux driven by a variable power source comprising; power detection means to detect a electrical output of said electrical power generator; means to maintain a required speed of said electrical power generator substantially independent of wind turbulence effects; means including fuzzy logic control means to determine the optimum operation of said electrical power generator which will provide improved efficiency; and said fuzzy logic control means responsive to said power detection means to vary said airgap magnetic flux of said electrical power generator in increments to modify said speed of said generator to further improve said efficiency; wherein said variable power source is wind and wind turbine is provided to rotate said generator in response to said wind; said fuzzy logic control includes means to vary said airgap magnetic flux of said generator and at least one fuzzy logic controller to generate a flux control signal to vary said airgap flux; said means to maintain the speed of said electrical power generator include solid state electronic converters; and said fuzzy logic control further includes a second fuzzy logic controller to provide a signal for adjusting said variable speed generator for maximum power.

Claim 15

An efficient integrated intelligent controller for a variable speed generator including an air gap with magnetic flux driven by a variable power source comprising; power detection means to detect a electrical output of said electrical power generator; means to maintain a required speed of said electrical power generator substantially independent of wind turbulence effects; means including fuzzy logic control means to determine the optimum operation of said electrical power generator which will provide improved efficiency; and said fuzzy logic control means responsive to said power detection means to vary said airgap magnetic flux of said electrical power generator in increments to modify said speed of said generator to further improve said efficiency; wherein said variable power source is wind and wind turbine is provided to rotate said generator in response to said wind; said fuzzy logic control includes means to vary said airgap magnetic flux of said generator and at least one fuzzy logic controller to generate a flux control signal to vary said airgap flux; said means to maintain the speed of said electrical power generator include solid state electronic converters; and said fuzzy logic control further includes a second fuzzy logic controller to provide a signal for adjusting said variable speed generator for maximum power.

Claim 16

The improved integrated fuzzy logic control of claim 11 wherein said fuzzy logic control further includes a third fuzzy logic controller to provide a fuzzy logic based adaptive speed loop controller to substantially eliminate wind turbulence effects and maintain substantially constant frequency of the output electric power provided by said generator.

Claim 17

The integrated fuzzy logic control of claim 12 wherein said solid state converters include at least one pulse width modulated inverter and at least one pulse width modulated rectifier.

Claim 18

The integrated fuzzy logic control of claim 13 wherein said solid state converters include at least one insulated gate bipolar transistor connected in parallel with a rectifier and forming a converter element.

Claim 19

The integrated fuzzy logic control of claim 14 wherein a plurality of said converter elements are connected in parallel to handle increased electric power.

Claim 20

The integrated fuzzy logic control of claim 15 wherein said inverter and said rectifier are connected by a DC link including at least on filter capacitor.

Claim 21

The integrated fuzzy logic control of claim 13 wherein a first pulse width modulated controller is provided to control the operation of said pulse width modulated inverter, and a second pulse width modulated controller is provided to control the operation of said pulse width modulated rectifier.

Claim 22

The integrated fuzzy logic control of claim 17 wherein each of the pulse width modulated controllers receives control signals provided by the fuzzy logic flux controller and from said fuzzy logic adaptive speed loop controller.

Claim 23

The integrated fuzzy logic control of claim 18 wherein said first pulse width modulated controller receives a control signed provided by the fuzzy logic power output controller.

Claim 24

The integrated fuzzy logic control of claim 11 wherein said at least one fuzzy logic controller utilizes a rule base which is substantially: ______________________________________ ΔPo\LΔW.sub.r P ZE N ______________________________________ PVB PVB PVB NVB PB PB PVB NB PM PM PB NM PS PS PM NS ZE ZE ZE ZE NS NS NM PS NM NM NB PM NB NB NVB PB NVB NVB NVB PVB ______________________________________ wherein: N is negative P is positive PVB is positive very big PB is positive big PM is positive medium PS is positive small ZE is zero NS is negative small NM is negative medium NB is negative big NVB is negative very big.

Claim 25

The improved integrated fuzzy logic control of claim 12 wherein said at least one fuzzy logic controller utilizes a rule base which is substantially: ______________________________________ E\CE NVL NL NM NS ZE PS PM PL PVL ______________________________________ NVL NVB NB NM NS ZE NL NB NM NS ZE PS NM NB NM NS ZE PS PM NS NB NM NS ZE PS PM PB ZE NB NM NS ZE PS PM PB PS NB NM NS ZE PS PM PB PM NM NB ZE PS PM PB PL NS ZE PM PM PB PVL ZE PS PM PB PVB ______________________________________ wherein: N is negative P is positive PVB is positive very big PB is positive big PM is positive medium PS is positive small ZE is zero NS is negative small NM is negative medium NB is negative big NVB is negative very big.