Controller for Free Piston Generator

A controller for a free piston generator that generates power by causing a piston with a magnet embedded therein to reciprocate in a cylinder provided with a coil, the cylinder having a combustion chamber therein, the controller being configured to:

• set a first velocity command value for an expansion stroke in which the piston is moved away from the combustion chamber and a second velocity command value for a compression stroke in which the piston is moved toward the combustion chamber;
• and
• control an amount of power generation to cause a velocity of the piston to reach the first and second velocity command values by electric braking during power generation, or control an amount of power supply to cause the velocity of the piston to reach the first and second velocity command values by exciting the coil during motoring,
• wherein setting the first and second velocity command values comprises setting first and second velocity command values for a certain round-trip period based on a top dead center position, at which the piston is located closest to the combustion chamber, and a bottom dead center position, at which the piston is located most far away from the combustion chamber, for the previous round-trip period.