Power supply control method and power supply device for electron beam generating system of electron beam bombardment furnace

Abstract

The present invention is a control method and a power supply device for the power supply of the electron beam generation system of the electron beam bombardment furnace. This method controls the open-loop control of the acceleration power supply, and the acceleration voltage and electron beam current sampling signals are used as control signals for the bombardment power supply, filament power supply and electron beam power. The coordinated work of the three power sources makes the power of the electron beam easy to adjust and stable. Small harmonics have little impact on the power grid, high power factor and efficiency of equipment, and reliable operation. The primary side of the main transformer of the accelerating power supply of the power supply device is connected to the three-phase power, and the output terminal is connected to the accelerating voltage divider circuit and the electron beam current sampling resistor to output the sampling signal. The accelerating power supply is also connected with a thyristor device, a trigger circuit, a soft start control circuit, a fault detection protection control circuit, and the like. The bombardment power supply includes PWM, bombardment inverter, bombardment transformer, bombardment power regulator, etc. Filament power supply and beam power control circuit includes PWM, filament inverter, filament transformer, beam power setting potentiometer, multiplier, beam power regulator and filament power regulator, etc.

Description

(1) Technical field [0001] The invention relates to electron beam electric heating equipment, in particular to a power supply control method and a power supply device for an electron beam generating system of an electron beam bombardment furnace. (2) Background technology [0002] The electron beam bombardment furnace is an electrothermal equipment that uses the heat energy generated when high-speed electrons bombard the charge for melting and heating. Compared with other vacuum melting furnaces, it has high power density and can be used for smelting and refining precious, rare and refractory metals. The vacuum degree in the furnace is high, and it is easy to prepare various high-purity materials or Special alloys and used for smelting high-quality special steel and titanium waste recycling, etc. In addition, it also has the advantage of no refractory material pollution to the charge. The development direction of the electron beam bombardment furnace is high power and multi...

AI Technical Summary

Problems solved by technology

[0009] 1) The harmonic amplitude of the input current on the AC side is large, causing serious pollution to the power grid and forming a "public nuisance" of electricity;

[0010] 2) Phase-shift voltage regulation increases the current lag phase angle, and the power factor becomes lower;

[0011] 3) In order to ensure the adjustment volume requirements, the main transformer capacity design has a large margin, the utilization rate is low, the loss of the main transformer is large, and the operating efficiency is not high;

[0012] 4) The input voltage waveform of the main transformer is a non-sinusoidal wave, and the high-order harmonic voltage and current increase the iron consumption and further reduce the operating efficiency;

[0013] 5) The non-sinusoidal voltage supply of the main transformer makes the rectified output voltage ripple larger, which increases the difficulty of filtering, and the final output acceleration voltage still has a high ripple coefficient;

[0014] 6) The large output voltage ripple is not conducive to the focus of the electron beam, reduces the flow rate of the electron beam in the electron gun, causes the operating temperature of the electron gun to be too high, and the operating efficiency decreases

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