| 摘要 |
A circuit for controlling a medium frequency x-ray diagnostics generator, the generator having a power rectifier connected to a main power source having an unknown internal resistance. A low-voltage filter stage, and inverter, a high-voltage transformer, and a high-voltage rectifier are connected in sequence between the power rectifier and an x-ray tube. A control unit for the x-ray tube is provided which controls the x-ray tube input current dependent upon the input voltage to the inverter, so that the x-ray tube voltage is maintained constant independently of the internal network resistance of the main. The generator can thus be connected to different mains having different internal resistances without affecting operation of the x-ray tube, making the generator suitable for use as a portable generator. A capacitance connected in the generator preceding the inverter, such as in the low-voltage filter stage, insures that the inverter input voltage will change more slowly than a rate at which the x-ray tube current can be changed.
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