US Patent No. 9,444,379

WIND POWER EXCITATION SYNCHRONOUS GENERATION SYSTEM HAVING MAXIMUM POWER DETERMINING UNIT AND CONTROL METHOD THEREOF


Patent No. 9,444,379
Issue Date September 13, 2016
Title Wind Power Excitation Synchronous Generation System Having Maximum Power Determining Unit And Control Method Thereof
Inventorship Tzuen-Lih Chern, Kaohsiung (TW)
Der-Min Tsay, Kaohsiung (TW)
Jao-Hwa Kuang, Kaohsiung (TW)
Guan-Shyong Hwang, Kaohsiung (TW)
Li-Hsiang Liu, Kaohsiung (TW)
Wei-Ting Chen, Kaohsiung (TW)
Ping-Lung Pan, Kaohsiung (TW)
Tsung-Mou Huang, Kaohsiung (TW)
Assignee NATIONAL SUN YAT-SEN UNIVERSITY, Kaohsiung (TW)

Claim of US Patent No. 9,444,379

1. A control method of a wind power excitation synchronous generation system, wherein the control method comprises the following
steps of:
detecting an output voltage, an output current and an output power of an excitation synchronous generator by using a power
detector, so that a real-time output power information is obtained;

using a motor to control a driving of a transmission mechanism, wherein the transmission mechanism is connected between a
wind turbine rotor and the excitation synchronous generator to drive the excitation synchronous generator;

using an encoder to transmits a position information of the excitation synchronous generator to a digital signal processing
controller;

using a phase detector to obtain and transmit a phase information of a utility grid to the digital signal processing controller;
transferring the phase information of the utility grid into a present position command;
comparing the present position command with the position information of the excitation synchronous generator to determine
a duty cycle width of a pulse width modulation controlling unit, and to output a power switch timing to a power driving inverter
for driving the motor;

performing a position servo control of the motor according to the position information of the excitation synchronous generator,
so as to allow the transmission mechanism to drive the excitation synchronous generator at a predetermined speed, thereby
generating the output power;

transmitting the output power to the utility grid in parallel;
using a maximum power determining unit to generate a power command according to a sum of a reference wind power and a fine-tuning
power, wherein the reference wind power is defined by a pitch angle of the wind turbine rotor and a reference wind speed,
and the fine-tuning power is defined as a function of a motor input power;

tracking a predetermined power of the power generation system by the power command;
wherein the real-time output power information is fed back to a power controller to compare with the power command, and the
power controller is used for generating an excitation current command to an excitation controlling unit, and the excitation
controlling unit is used for generating an excitation current for controlling an excitation field of the excitation synchronous
generator.