Patent ID: 7614240

Claim:
A method of controlling a pulse tube cryocooler to maintain a refrigeration load at a set point temperature or to move a refrigeration load towards the set point temperature, said method comprising: sensing a temperature referable to refrigeration load temperature of the refrigeration load; controlling power input to an acoustic source of the pulse tube cryocooler by increasing the power input when the temperature rises above the set point temperature and reducing the power input when the temperature falls below the set point temperature; and adjusting impedance of an inertance network of the pulse tube cryocooler in response to the temperature referable to the refrigeration load temperature and the power input to the cryocooler such that a maximum cooling power to the refrigeration load is obtained from the pulse tube cryocooler at the temperature referable to the refrigeration load temperature and at the power input to the acoustic source.