Power generation system and method of controlling same

A power generation system comprising:

• a continuously variable transmission including a transmission mechanism configured to steplessly change a speed change ratio, the continuously variable transmission being configured to transmit a rotational speed of an input shaft to an output shaft at the speed change ratio changed by the transmission mechanism;
• a power generator driven by rotation of the output shaft to generate three-phase AC power;
• a transmission driving device configured to drive the transmission mechanism such that the speed change ratio of the continuously variable transmission is changed to a commanded gear change value corresponding to an input gear change command;
• an output-side speed detector configured to detect an output-side rotational speed that is a rotational speed of the output shaft;
• an electric power load calculation device configured to calculate electric power load of the power generator;
• and
• a controller configured to output the gear change command corresponding to a detection result of the output-side speed detector and the electric power load calculated by the electric power load calculation device, control the speed change ratio of the continuously variable transmission, and make the power generator generate the three-phase AC power of a predetermined set frequency, wherein:
• the electric power load calculation device includes a current detector, a voltage detector, and a calculator;
• the current detector detects current values of respective phases of a three-phase alternating current generated by the power generator;
• the voltage detector detects voltage values of the respective phases of the three-phase alternating current generated by the power generator;
• the calculator calculates the electric power load of the power generator based on the current values detected by the current detector and the voltage values detected by the voltage detector, and executes filtering work of attenuating a higher harmonic of the set frequency when calculating the electric power load of the power generator;
• the controller includes a feedback control portion and a feedforward compensation portion;
• the feedback control portion executes feedback control of calculating the gear change command and outputting the obtained gear change command to the transmission driving device such that the output-side rotational speed detected by the output-side speed detector becomes equal to an output-side target rotational speed corresponding to the set frequency;
• and
• the feedforward compensation portion executes feedforward compensation of correcting the gear change command, calculated by the feedback control portion, based on the electric power load of the power generator, the electric power load being calculated by the calculator.