SU1762391A1 - Pulse generator - Google Patents

Abstract

The invention relates to a pulse technique and can be used in the non-destructive testing of the mechanical properties of ferromagnetic products. The pulse generator contains a transformer (1), three capacitors (2, 14, 15), a resistive divider (3), a rectifier (4), a choke (5), two controllable valves (6. 7), a comparison circuit (9) , delay unit (10), master oscillator, two pulse drivers (12, 13). Switching the capacitor 14 parallel to the output of the rectifier 4, and the capacitor 15 between the output winding of the transformer 1 and the input of the rectifier 4, when choosing the ratio of capacitors 14 and 15 of at least two to one, allows for a more uniform load on the transformer 1. 1 .

Description

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The invention relates to a pulsed i technology and can be used for non-destructive testing of the mechanical properties of ferromagnetic products.

The purpose of the invention is to increase the efficiency and reduce the level of interference by providing a more uniform over the loading period of the power transformer.

The invention is illustrated in the drawing, which shows the electrical circuit of the device.

The pulse generator contains a power transformer 1, the first capacitor 2, in parallel with which is connected a resistive divider 3, a series-connected rectifier 4, a choke B, the first controlled valve 6. the second controlled valve 7 and the load 8, the E comparison circuit, one input which is connected to the source of the reference voltage, and the output is connected to the input of the delay unit 10 and the blocking input of the master oscillator 11. The first driver 12 pulses, the input of which is connected to the output of the master oscillator 11, and the output It is connected to the input of the controlled valve 6, the second pulse shaper 13, whose input is connected to the output of the delay unit 10, and the output is connected to the input of the controlled valve 7, the second capacitor 14 connected in parallel to the output of the rectifier 4, the third capacitor 15 connected between the secondary the winding of the transformer 1 and the rectifier 4, and the capacitances of the capacitors 14 and 15 are not less than two to one.

The device works as follows.

With a positive half-wave at the output of transformer 1, rectifier 4 starts charging capacitors 15 and 14, the distribution of voltages between them occurs in inverse proportion to their capacitances. When the voltage on capacitor 14 reaches a value sufficient to open and hold valve 6, capacitor 14 the pulse of the former 12 is discharged through the valve of the capacitor 2, the choke limits the current through the valve 6. The charge of the capacitor 2 is also due to the charge of the capacitor 15. When the charging current decreases below the current holding valve 6, the charge process is stopped. The process repeats as soon as the voltage on the capacitor 14 exceeds the voltage on the capacitor 2 plus the voltage required to open the valve 6 until the charge on the capacitor 15 has finished. At the end of the charge

the capacitor 15 is the total voltage on it and the capacitor 14 is equal to the amplitude voltage of the secondary winding of the transformer 1, and the voltage on the capacitor 14 is approximately equal (slightly higher) to the voltage on the capacitor 2. When the voltage on the secondary winding of the transformer 1 decreases ) to the level when it

0 in sum with the residual voltage on the capacitor 14 is less than the absolute value of the voltage on the capacitor 15, the charging of the capacitor 14 starts. When the voltage on it exceeds the voltage of the capacitor 2 plus the voltage required to open the valve 6, and in the presence of a pulse from the driver 12, another discharging of the capacitor 2 occurs.

0The process is repeated until reboot.

the capacitor 15 to the negative half-wave voltage on the secondary winding of the transformer 1.

Further, the process is repeated until

5 when the voltage across the capacitor 2 reaches the voltage at which the comparison circuit 9 operates, which blocks the master oscillator 11. The shaper 12 is also blocked, control pulses

0 cease to flow to valve 6 and it is in the closed state (when the current drops below the holding current). The signal from the comparison circuit 9 through the delay unit 10 starts the second driver 13 and 5 pulses. The delay occurs for the time required to close the valve 6. When the output pulses of the driver 13 are received, the valve 7 opens and the capacitor 2 is discharged to the load 8.

At the end of the discharge, the pulse shaper 13 (for example, the blocking oscillator) is again blocked, and the master oscillator 11 and the pulse shaper 12 are unlocked and the process starts again.

5 For stable operation of the device, it is necessary that the ratio of the capacitors of the capacitors 14 and 15 is not less than two to one. Otherwise, the transformer efficiency decreases and

0 surge current.

Claims (1)

Claims An impulse generator comprising a power transformer, a rectifier, to the output of which a series-connected choke is connected, the first controlled valve and the first capacitor, the second controlled valve connected to the load circuit of the first capacitor, sets the generator, whose exit through the first pulse driver is connected to the input of the first controlled valve; pulses, distinguished0 And in order to increase the efficiency and reduce the level of generated interference, a third capacitor is inserted, which is connected between the output winding of the power transformer and the rectifier input, the second capacitor is connected parallel to the rectifier output, the resistive divider is connected parallel to the first capacitor, and the capacitances of the second and third capacitors are related to at least two to one.