What are the forms of power supply for plasma spraying? What are the characteristics of each?

       (1) Magnetic amplifier type silicon rectifier power supply. Magnetic amplifier silicon rectifier power supply, simple in structure, reliable in use and convenient in current regulation, is a power supply widely used in the domestic plasma spraying industry. Table 6-7 gives the main technical parameters of several plasma spraying power sources.



    (2) Thyristor rectifier power supply. The steep drop characteristic of the thyristor rectifier power supply is realized by the current negative feedback regulation system. This kind of power supply has the characteristics of stable arc starting, stable output current and low power consumption. Compared with the magnetic amplifier type silicon rectifier power supply, the magnetic saturable reactor is omitted, and a lot of silicon steel sheets and steel materials are saved, so that the whole power supply has the advantages of small size, light weight, high efficiency and low cost.

    (3) Rectified inverter power supply. The rectifier inverter power supply is to invert the rectified pulsating DC power supply through the inverter into an AC square wave, and then rectify it into a non-pulsating DC power. The rectifier inverter power supply can meet the requirements of high power, high current, high working voltage, large inrush current, long continuous working time and strong high frequency interference required by supersonic plasma spraying. Therefore, this kind of power supply is an important development direction of the power supply of plasma spraying equipment. The main parameters of the power supply are: the accuracy of constant current is better than 1%; the accuracy of constant power is better than 5%; the maximum output current is 600A; the maximum working voltage is 220V; the maximum power is 80kW.