Abstract: Granules collected from a solution of a polycarbonate, an integrated structure of independent fine particles constituting the granules being formed at least on the surfaces of the granules; and a process for preparing the granules of the polycarbonate which comprises the steps of adding a poor solvent to the polycarbonate solution, and then agitation-granulating fine particles of the polycarbonate into the granules, while stirring involving a shear force-imparting function is carried out under heating. According to the present invention, the polycarbonate or the like can be collected from its organic solvent solution as the granules having good drying properties.

Abstract: A power converter having a thyristor converter connected to an AC power source to rectify its AC output, a DC intermediate circuit including a smoothing capacitor and receiving a rectified output from the thyristor rectifier and a voltage type inverter for converting a DC voltage applied from the DC intermediate circuit into an AC output voltage of a variable voltage and a variable frequency. The DC intermediate circuit has two series circuits, each having a diode and a transistor switch, connected in parallel with each other and to the both terminals of the thyristor converter. The junctions, each between the diode and the resistor, are connected to the both terminals of the smoothing capacitor. The two series circuits function to switch the connection polarities of the thyristor converter and the smoothing capacitor and to regulate the voltage across the capacitor with a limited current by a voltage step-up or step-down operation by the transistor switch.