Fluid power generator

• US 6,864,594 B2
• Filed: 11/08/2002
• Issued: 03/08/2005
• Est. Priority Date: 11/08/2001
• Status: Expired due to Fees

• Current Assignee: Kazuichi Seki
• Original Assignee: Tokai University Educational System
• Inventors: Seki, Kazuichi
• Primary Examiner(s): Ponomarenko, Nicholas
• Assistant Examiner(s): PHAM, LEDA T
• Application Number:
  US10/451,130
• Publication Number:
  US 20040041405A1
• Time in Patent Office: 851 Days
• Field of Search: 290/44, 290/55, 290/4.R, 290/4.C, 290/43, 290/54, 318/147
• US Class Current: 290/44
• CPC Class Codes: F03D 7/0272 by measures acting on the electrical generator
• CPC Class Codes: F03D 7/06 the wind motors having rotation axis substantially perpendicular to the air flow entering the rotor
• CPC Class Codes: F03D 9/007 the wind motor being combined with means for converting solar radiation into useful energy
• CPC Class Codes: F03D 9/11 storing electrical energy
• CPC Class Codes: F03D 9/25 the apparatus being an electrical generator F03D9/22 takes precedence
• CPC Class Codes: F05B 2270/32 Wind speeds
• CPC Class Codes: H02S 10/12 Hybrid wind-PV energy systems
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y02E 10/74 Wind turbines with rotation axis perpendicular to the wind direction
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin

Abstract

In a fluid power generator system using operative fluid energy, a measured tip speed ratio and a reference tip speed ratio are compared with each other. If the measured tip speed ratio is smaller than the reference tip speed ratio, a generator is placed in a no-load state, thereby restoring the number of rotations of the wing axial shaft to the number of rotations corresponding to the reference tip speed ratio. Further, the operation of the generator is controlled on the basis of the tip speed ratio calculated from the flow rate of the fluid, thereby providing a maximum output for each flow rate. In this way, a change in the flow rate and number of rotations can be appropriately dealt with and the maximum output for each flow rate of the operative fluid can be dealt with, thereby increasing a quantity of generated power.

Claims

1. A fluid power generator system including a generator coupled with a wing axial shaft which is rotated by operative fluid energy as a driving source and a load device including a battery connected to the generator, the fluid power generator system comprises:

a comparing means for comparing an measured tip speed ratio, said measured tip speed ratio being calculated by a flow-rate signal based on a flow-rate of the operative fluid and a number of rotations based on the number of rotations of said wing axial shaft, and said reference tip speed ratio providing a maximum conversion efficiency of the operative fluid energy in said fluid power generator system; and

a load control means for on/off controlling said load device so that if said measured tip speed ratio is smaller than said reference tip speed ratio as a result of comparison by said comparing means, said generator is placed in a no-load state, thereby restoring the number of rotations of said wing axial shaft to the number or rotations corresponding to said reference tip speed ratio said load control means being independent means for controlling a load which is applied to the generator; and

a braking including a revolving number detecting unit for detecting the number of revolutions of said wing axial shaft and a brake unit for braking the rotation of the wing, said braking means operating the brake when the flow-rate of the operative fluid exceeds a designated maximum value or when a detected signal form the revolving number detecting unit is abnormal.

2. A fluid power generator system according to claim 1, wherein said load control means places said generator in the no-load state if said measured tip speed ratio is smaller than said reference tip speed ratio as a result of comparison by said comparing means and continues the no-load state until said number of rotations is restored to the number of rotations corresponding to said reference tip speed ratio, thereby dealing with a change in the number of rotations of said wing axial shaft.

3. A fluid power generator system according to claim 1, wherein when the battery of said load device is fully charged, power supply to said battery is stopped by an output form an excessive voltage detecting unit and a dummy load is connected to said generator.

6. A fluid power generator system according to claim 1, wherein when the battery of said load device is fully charged, power supply to said battery is stopped by an output form an excessive voltage detecting unit and a dummy load is connected to said generator.

4. A fluid power generator system having a generator coupled with a wing axial shaft which is rotated by operative fluid energy as a driving source, said fluid power generator comprising a control means for controlling the operation of said generator on the basis of a measured tip speed which is calculated by a measured flow-rate of the operative fluid and a measured number of rotations of said wind axial shaft, thereby providing a maximum output for each flow-rate of the operative fluid;

and

a braking means including a revolving number detecting unit for detecting the number of rotations of said wing axial shaft and a brake for braking the rotation of the wing, the braking means controlling the rotational speed of the wiring axial shaft.

5. A fluid power generator system according to claim 4, wherein said control means constantly controls the operation of said generator on the basis of a measured tips speed ratio which is calculated from a measured flow rat of the operative fluid and higher number of rotations exceeding an output peak value at the measured number of rotations of the axial shaft, so that a maximum output for each flow rate of the fluid is obtained by a load given to said wing axial shaft.