SU492980A2 - Rectangular current pulse generator - Google Patents

Description

one

I Known generator of rectangular current pulses lo av.st. No. 428533, in which variable resistors are used for stepless frequency control. Such resistors lead to a significant reduction in the reliability of the control system and necessitate the introduction of amplifiers with a relatively large output power and output and voltage into the system.

The purpose of the invention is to create a non-contact control of the frequency or phase of the control current pulses and to reduce the value, power pattern and control voltage.

The proposed device is equipped with a current transformer, the porphyry winding of which is connected to a long line circuit, and the secondary winding bounded by a choke with a smooth change of inductance is connected via a diode to the capacitor of the time of the relaxer on the dynistor to the capacitor.

In addition, the device can be equipped with additional time

| a chain with a time constant greater than the main chain connected to the OG main chain through the diode in the conducting direction.

The current transformers connected to the capacitors of the time of the driving chains can be equipped with additional windings, which are connected in series with each other.

Figure 1 shows a schematic diagram of the generator, a general view; 2 shows the voltage and current patterns; FIG. 3 is a schematic diagram of the connection of the current transformer windings to each other and to the sources of the control signal and the power supply pulses with automatic control.

The current pulse generator contains dinistor 1, capacitors 2 and 3, counter-diode 4, limiting resistor 5, low-resolution resistor 6. Capacitor 2 and resistor 6 form the main time of the drive chain. Power relaxer. carried out from the output of the pulse former 1 through the current transformer 7

.-.-

I and the charging diode S. For an additional time, the driving circuit contains a capacitor 9 and a resistor 10. The capacitor 9 is charged with the same current impedance from the driver through a pulse transformer 11 and a diode 12.

The secondary winding of the pulse transformer 11 is shunted by the reactor 13 with a smoothly controlled inductive network.

Both times of the driver circuits are interconnected by a diode 14 connected in such a way that when capacitor 2 is discharged to a level less than voltage | on capacitor 9, both chains are connected in parallel and the voltage drop rate on the capacitors decreases significantly. The current pulses generated by the master oscillator are fed through a transformer 15 to its output.

In the initial state, the capacitors 2 3 and 9, as well as the capacitors of the artificial long line, are charged to voltages with a positive sign. The drive generator is driven by current pulses generated by the output stage through transformers 7 and 11.

When the contacts of the starting toggle switch 16 are closed at the moment of time, the capacitor 2 begins to discharge through resistors 6 and 1O. Since the time constant of the discharge of capacitor 9 is longer than the time of discharge of capacitor 2, and the voltage on both capacitors before starting was the same, diode 14 provides a parallel connection of both capacitors, their discharge will occur at the minimum speed and the voltage on the capacitor 2 will slowly decrease .2). At the moment of time, the voltage difference across capacitors 2 and 3 will become equal to the switching voltage of dynistor 1, which will activate it and generate a current pulse at the output of the control current driver.

The flow of current pulses through the primary windings of transformers 7 and 11 ensures a fast charge of capacitors 2 and the time of the driving circuits of the master oscillator. When charging the capacitor 2 to a voltage equal to the voltage on the capacitor 3, the dynistor 1 is switched off and the current pulse at the generator output drops.

The fall of the current pulse at the output of the form world j jets to zero causes a repeated expansion

a row of capacitor 2 through a resistor 6 with a constant time determined by the capacitance of the capacitor 2 and the resistance of the resistor 6. At the time point of the voltage "5, the capacitor 2 will become equal to the voltage on the capacitor 9 and the current in the diode circuit 12 A sharp decrease in the rate of voltage drop across capacitor 2 will increase. From now on, the discharge time constant will be determined by the resulting capacitance of capacitors 2 and 9 connected in parallel, and the resistance of resistors 6 and 10. The decrease in voltage on condensation 5 iTOpe 2 causes an increase in the voltage on dynistor 1 and its repeated activation. The processes are repeated. Adjusting the pulse repetition rate in the proposed driver is implemented by changing the inductance of the reactor 13, which shunt the pulse transformer 11.

Reducing the inductance of the reactor 13, for example, by increasing the core gap,

5 leads to a decrease in the constant component of the current in the diode circuit of 12 n voltage on the capacitor 9. At the same time, the voltage on the capacitor 2 decreases rapidly to a lower level, J4TO reduces the period of pulsing of the pulses generated by the master oscillator, and consequently, y: increasing the pulse repetition rate at the output of the proposed pulse former

5 current.

When using the proposed device in automatic control systems, the control signal is removed from the shunt used to measure current,

 and is supplied to the auxiliary control winding circuit on the pulse transformer 11. The flow of direct current in the control winding provides, depending on the voltage, either the magnetization of the transformer core or its demagnetization, causing, respectively, a decrease capacitor 9,; its increase and the corresponding change in the repetition rate of current pulses at the output of the driver.

The proposed device allows to increase the sensitivity to the automatic control signal. In this case, the pulse transformers 7 and 11 are supplied with additional control windings. Since the control windings are connected consistently, and the primary windings are

pulse transformers are counter-sequential, then with increasing current in the control windings, additional core magnetisation of transformer 11 occurs in demagnetization of transformer core 7, which causes a decrease in the maximum voltage on the capacitor 9 and an increase in the voltage on the capacitor 2 current pulses at the output of the pulse former. The inclusion of the windings of pulse transformers eliminates the possibility of current pulses in the circuit of the control windings and the source of the control signal (see Fig. 3).

Claims (2)

1. The generator of rectangular current pulses 20 ave, aut., No. 428533, characterized in that, for the purpose of non-contact frequency control, it is equipped a current transformer, primary washing, which is connected to a long line circuit, and the secondary winding, shunted by a choke with a smooth inductance change, is connected to a capacitor through the diode to the time of the reference circuit of the relaxator on the dynistor. 2. The generator according to claim 1, in respect of the fact that, in order to increase the frequency variation limits, it is equipped with an additional time < Descale & with a constant time, a larger, main chain connected to the main chain through a diode in the conducting direction. 3, The generator according to claim 1, in order to increase the sensitivity and reduce the control power, the current transformers connected to the capacitors of the time of the driving chains are provided with additional windings Kami, which are connected according to in-series. W 1 R p / i i / e. one 2fj t is t-o f-o / fPt8.2 .-Tl. 7 J fj Ly n L