SU1626362A2 - Linear pulse modulator - Google Patents

Abstract

The invention relates to a pulse shaping technique and can be used primarily in microwave transmitters. The purpose of the invention is to reduce power consumption. The goal is achieved by introducing the third winding 21 on the first transformer 2, the second rectifier 22, the charging resistor 23, the capacitor 25, the third key transistor 24, the second transformer 26, the decoupling diode 27, the third coincidence element 29 and Inverter 28. The device also contains a DC power supply 1, first and second key transistors 3 and 4. First rectifier 5, charge choke 7, charge diode 8, charge choke 6, formation line 9, load 10, sensors a charging current 11. The switch 12, synchronizer 13, a trigger 14, unit 15 generating control pulses, a counter-valve 16, even 18 and odd 17 of matching elements, the first OR gate 19, a second OR gate 20. The 2-yl. cl

Description

The invention relates to a technique of forming pulses, can be used primarily in microwave transmitters, as well as to power modulator microwave generators and is an improvement of the invention according to the author. St. No. 1437985.

The purpose of the invention is to reduce power consumption.

FIG. 1 shows the electrical circuit diagram of the modulator; in fig. 2 shows the voltage and current plots of the modulator at m 4.

The linear pulse modulator contains a direct current power supply 1, the first transformer 2, the primary winding of which contains two half windings connected according to, their common point connected to the positive pole of the power source 1, the first and second key transistors 3 and 4 , the collectors of which are connected to the primary half windings, the first rectifier 5, the input connected to the second winding 6 of the first transformer 2, the charge throttle 7. the input connected to the positive pole of the rectifier 5, the charge diode 8, the anode connected to the output of the charge throttle 6, the line 9 of formation, the input connected to the cathode of the charging diode 8, the load 10, the sensor 11 of the charging current connected to the load circuit 10, the switch 12, the anode connected to the cathode of the charge diode 8, the synchronizer 13 the output of which is connected to the control input of the switch 12, the trigger 14, the counting input of which is connected to the output of the synchronizer 13, the control pulse shaping unit 15, the input of which is connected to the forward output of the trigger 14, the distributor 16 t + 1 pulses, where m is even h layer, the counting input of which is connected to the output of the control pulse generation unit 15, and the installation input to zero with the inverse output of the trigger 14, m coincidence elements, divided into odd 17 and even 18, the first inputs of which are connected to the output of the unit 15 forming the control pulses, and the second inputs are connected to odd and even outputs of the counter-distributor 16, respectively, the first element AND PI 19, the inputs of which are connected to the outputs of the matching element 18, and the output to the base of the key transistor 3, the second element OR 20, in ode which are connected to outputs 18 of matching elements, with the third input of the mth element 18 connected to the output of the sensor 11, the charging current, and an output of OR 20 is connected

with the base of the second key transistor 4, the third winding 21 on the first transformer 2, the second rectifier 22, a variable input connected to the terminals of the third winding 21, the charging resistor 23. the first output connected to the positive terminal of the second rectifier 22. the third key transistor 24, the capacitor 25, the first output connected to the second output of the charging resistor 23 and the collector of the third key transistor 24, the second transformer 26. the end of the primary winding of which is connected to the second output of the capacitor 25, and its beginning - with emit The third key transistor 24 and the negative output of the second rectifier 22, the decoupling diode 27, the cathode connected to the connection point of the positive output of the first rectifier 5 and charge throttle 7, and the anode to the beginning of the secondary winding of the second transformer 26, the end of which is connected to a common bus, an inverter 28, an input connected to the output of the control pulse shaping unit 15, a coincidence element 29, the first input of which is connected to the direct output of the trigger 14, the second to the output of the inverter 28, the third to the output of the sensor 11 ar-stand current and output - with a base of the third transistor 24.

The modulator operates as follows.

When applying a short-term positive triggering pulse from the output of the synchronizer 13 to the counting input C of the trigger 14 (Fig. 2a), the latter changes its state, while the logical 1 from the direct output of the trigger 14 (Fig. 26) enters the input of the control generation unit 15 pulses and to the first input of the element 29 coincidence, and logical 0 from the inverse output of the trigger 14 to the input of setting the zero of the distribution counter 16, preparing it for the counting mode. At the output of the control pulse shaping unit 15, pulses are generated, the form of which is shown in FIG. 2c, while the frequency of their repetition is equal to

Fn 2fnp, where fnp is the switching frequency of the transistors

Zi4

and the duration of the pause between them is chosen based on the condition of excluding the occurrence of the through current through the key transistors 3 and 4 at the moments of their switching. The generated pulses arrive at the counting input C of the counter-distributor 16, to the input of the inverter 28 and the first inputs m of the elements 17 and 18 of coincidence, to the second inputs of which pulses are fed from the outputs of the counter-distributor 16 (Fig. 2 g, e, g) . At the same time, the odd pulses from the outputs of the odd elements 17 match through the first element OR 19 arrive at the base of the first key transistor 3 (Fig. 2h), and the even pulses from the outputs of the even elements 18 match through the second element OR 20 to the base of the second key transistor 4 ( Fig. 2i). These transistors commute the primary half windings of the first transformer 2, as a result of which the secondary windings 6 and 21 form alternating voltages, which are rectified by rectifiers 5 and 22, respectively (Fig. 2k). When the first pulse arrives, the line 9 starts charging through the charging choke 7, the charging diode 8, the load 10 and the charging current sensor 11 (Fig. 2n), and the logical 1 is formed at the output of the last (Fig. 2p), which enters on the third inputs of elements 19 and 29, coincidence. At the same time, the pulse at the output of the rectifier 22 through the charging resistor 23 is fed to a capacitor 25, which is charged through the primary winding of the second transformer 26 to the amplitude of the pulse (Fig. 2m). After the termination of the first pulse at the moment when a pause appears at the output of the control pulse forming side 15, the logical 1 is formed at the output of the inverter 28 (FIG. 2L), which arrives at the second input of the coincidence element 29, while due to the presence of logical 1 at the other inputs An output voltage pulse is generated, the duration of which is equal to the duration of the pause. It is applied to the base of the third key transistor 24, which is opened. The capacitor 25 is discharged to the primary winding of the second transformer 26, on the secondary winding of which a positive polarity voltage pulse is generated (Fig. 2n), which through the decoupling diode 27 enters the modulator charging circuit. As a result, during a pause in the operation of the key transistors 3 and 4, the energy for charging line 9 comes from the second transformer 26. When the next pulse arrives from the control pulse shaping unit 15, a logical O is formed at the second input of the coincidence element 29, which causes the third to close. key transistor 24. The next charge of the capacitor 25 occurs. The process of forming the charging voltage is repeated. As a result, the charging voltage of the line 9 is formed at the input of the charging circuit of the modulator (Fig. 2). After a full charge of the line 9 at the output of the charge current sensor 11, a logical O is generated, which is fed to the third input of the coincidence element 29, thereby preventing the opening of the third key transistor 24 after charging the line 9. In

In this case, the discharge of the capacitor 25 occurs through the leakage resistance of the circuit.

Thus, in the modulator, by introducing an additional source of pulsed voltage synchronized with the operation of the main source of charging voltage, continuous formation of the line of formation line is achieved, which is equivalent to an increase in the quality factor of the charging circuit. This makes it possible to reduce the amplitude of the charge pulses, which leads to a decrease in the switching power of the transistor's key transistors.

Claims (1)

Invention Formula Linear pulse modulator auth. St. ISfe 1437985, characterized in that, in order to reduce power consumption, a third winding is additionally introduced on the first transformer, the second rectifier, the charging resistor, the capacitor, the third key transistor, the second transformer, the decoupling diode, the third coincidence element, and the inverter; the terminals of the third winding are connected to the variable input of the second rectifier, the positive output of which is connected through the charging resistor with the collector of the third key transistor and the first terminal of the capacitor, the second terminal of which is connected to the end of the primary winding of the second transformer, and the beginning of the winding is connected to the negative output of the second rectifier and the emitter of the third key transistor, the base of which is connected to the output of the third element of coincidence, the input of the inverter is connected to the output of the control pulse shaping unit, and the output to the second input of the third element of coincidence, the first input of which is connected to the forward output of the trigger of the charge current sensor; in this case, the beginning of the secondary winding of the second transformer is connected through the isolating diode to the point the connections of the charge throttle and the first rectifier, and the end to the common bus.