| Patent application number | Description | Published |
|---|
| 20080277938 | Wind Power Generation System and Operating Method Thereof - A wind power generation system wherein procedure for controlling the blade pitch is changed in accordance with the rate of decrease in the amplitude of the grid voltage, and when over current occurs in the grid-side power converter, the grid-side power converter is brought into the gate-blocked condition whereas the generator-side power converter continues its operation. | 11-13-2008 |
| 20080296898 | Wind Power Generation System and Method of Controlling Power Converter - A wind power generation system temporarily stops a power converter when a system disturbance occurs, and reactivates the power converter after detecting a solution of the problem of an influence (overcurrent of a stator, direct current component of a stator, overcurrent of a rotor, etc.) of a fault occurring in a doubly-fed generator during a system fault. During a system fault, a reactive current can be safely output from a doubly-fed generator to an electric power system without destroying equipment of the wind power generation system. | 12-04-2008 |
| 20080304188 | Wind Power Generation System and Control Method Thereof - In a wind power generation system, an energy consuming unit is connected to a DC part of a generator-side converter. A shunt circuit is connected between the generator-side converter and a rotor of an AC-excited power generator. In the event of system failure, the switching operation of the converter is stopped, the shunt circuit is put into operation, and the energy consuming unit is put into operation so that DC voltage (voltage of the DC part) is maintained within a prescribed range. | 12-11-2008 |
| 20090066297 | Power Generation Apparatus Using AC Energization Synchronous Generator And Method Of Controlling The Same - A power generation apparatus and method includes an AC energization synchronous generator, a switching device which connects to a network disposed on a stator side of the AC energization synchronous generator, an energizing device which applies a variable frequency AC to a secondary winding of the AC energization synchronous generator, and a first voltage detection unit which detects a voltage of the switching device on the stator side. A rotational frequency of the AC energization synchronous generator is estimated or calculated based on a frequency of a stator side voltage of the switching device, while the switching device is open. | 03-12-2009 |
| 20090168474 | POWER CONVERTING DEVICE AND METHOD FOR CONTROLLING THE SAME - In a system to which a fluctuating load is connected, compensating for fluctuation in voltage harmonics at the load connecting point and fluctuation in system current harmonics has been difficult for a power converting device connected in parallel with the load. To resolve the problem, a power converting device connected in parallel with a fluctuating load includes: a Fourier series expansion unit which executes Fourier series expansion to load current by use of a reference sine wave in sync with a system and thereby outputs Fourier coefficients; and a fundamental component calculating unit which calculates a positive phase active fundamental component of the load current from the Fourier coefficients. A current instruction of the power converting device is generated by subtracting the fundamental current from the load current. With the current instruction, the fluctuations in system current harmonics and in voltage harmonics at the connecting point can be compensated for. | 07-02-2009 |
| 20090200803 | WIND POWER GENERATION SYSTEM - In a wind power generation system, an AC input of a unit for coping with system faults is connected to an excitation converter and a DC port of the unit for coping with system faults is connected to a DC port of a converter through resistors. A plurality of energy consumptive circuits each constructed of a resistor and switching units are provided for the DC port of the unit for coping with system faults. | 08-13-2009 |
| 20090261589 | Wind Power Generation System And Operation Method Thereof - A wind power generation system wherein procedure for controlling the blade pitch is changed in accordance with the rate of decrease in the amplitude of the grid voltage, and when over current occurs in the grid-side power converter, the grid-side power converter is brought into the gate-blocked condition whereas the generator-side power converter continues its operation. | 10-22-2009 |
| 20090278354 | Wind turbine generator system - In a wind turbine generator system including an AC exciting converter a grid side converter, and a controller configured to control the AC-exciting converter and the grid side converter, the controller operates a short-circuiting circuit when decrease in the grid voltage and increase in the DC voltage are detected. | 11-12-2009 |
| 20100038908 | WIND TURBINE GENERATOR SYSTEM - A wind turbine generator system can regulate the rotational velocity of the wind turbine within an operation range even when the wind velocity suddenly changes and can perform continuous operation of the wind turbine. The wind turbine generator system includes a generator connected to the shaft of the wind turbine and a converter connected to the generator. When the rotational velocity of the wind turbine is within a predetermined range, power outputted from the generator is controlled so as to follow the instruction concerning the generator output given from the wind turbine to the converter. When the rotational velocity of the wind turbine is out of the predetermined range, the power outputted from the generator is controlled without following the instruction concerning generator output given from the wind turbine to the converter. | 02-18-2010 |
| 20100102560 | Wind Power Generation Apparatus, Wind Power Generation System And Power System Control Apparatus - A power system control apparatus which controls a power system electrically connected to a wind power generation apparatus having a wind turbine which receives wind and rotates, a generator which generates electric power by the rotating wind turbine, and a power converter which converts the electric power generated by the generator. The power system control apparatus includes a voltage detector for detecting a voltage of the power system, a reactive power command value generation unit for generating a reactive power command value from a voltage detection value of the voltage detector, and a transmission unit for transmitting the reactive power command value to the wind power generation apparatus. Output fluctuation of the generator is suppressed, and reactive power according to the reactive power command value is transmitted from the wind power generation apparatus to the power system. | 04-29-2010 |
| 20100117606 | DISTRIBUTED GENERATION SYSTEM AND POWER SYSTEM STABILIZING METHOD - A distributed generation system that can suppress a voltage fluctuation caused by a distributed generation by an apparatus of a small power capacity in the distributed generation itself and stabilize the power system voltage without inserting interharmonic voltage or current into the power system and without interference among a plurality of distributed generations. Parameter α(t) varying with time is estimated based on fluctuating component ΔP of the active power P generated by the distributed generation and the voltage fluctuating component ΔV attributable to the distributed generation developed at the point of connection between the distributed generation and power system. The distributed generation produces reactive power Q=−αP or Q=−αΔP, to thereby suppresses only the voltage fluctuation of the power system attributable to the distributed generation. | 05-13-2010 |
| 20100201330 | WIND POWER GENERATION SYSTEM - A wind power generation system includes an excessive current consumption device, an AC input of which is connected between a generator rotor and an excitation converter on a system failure to detect a DC voltage ascent of the excitation converter and operate a shunt circuit on the system failure. | 08-12-2010 |
