SU1275705A1 - A.c.voltage-to-d.c.voltage converter - Google Patents

Abstract

The invention relates to the field of electrical engineering and can be used as a powerful transformerless power source of constant voltage. The purpose of the invention is to increase the reliability of the converter. The device contains controllable valves 5 and 6 of the cathode group and uncontrollable valves 7 and 8 of the anode group, connected to the output terminals 3 and 4, filter capacitor 9, additional power supply 10, parametric voltage regulator 11, control pulse driver 14, diode 29, as well as additionally introduced current generator 21, transistor g tor 28 and diodes 30 and 31, Generator then (L ka 21 introduced into the control circuit 1 h e cd o cd

Description

charging current, and its input is connected to one plate of a capacitor 26, the other plate of which is connected to the output of a parametric voltage regulator 11 and the cathode of diode 29. The diode 29 anode is connected to the collector of transistor 28 and one plate of a capacitor 27. Another plate of the capacitor 27 is connected to the emitter of the transistor 28 and the anode of the diode 31, the cathode connected to the positive output port 4. The collector of the transistor 28 is connected to the cathode of the diode 30, the anode connected to the input of the current generator 21. The base of the transistor 28 is connected and the output terminal 4. The introduction of these elements and their connection to other elements of the device providing smooth start device, wherein the emergency modes are completely absent in the starting current circuit. This achieves the supplied chain. ; 2 Il.

The invention relates to electrical engineering, in particular, to converter technology, and can be used as a powerful transformerless DC power source. The purpose of the invention is to increase reliability by ensuring a smooth start. Figure 1 shows the principle of the converter circuit; Fig. 2 shows time and voltage charts. The device contains input pins 1 and 2, output pins 3 and 4, controlled valves 5 and 6 of the cathode group and uncontrolled valves 7 and 8 of the anode group connected to negative output terminal 3, a filter capacitor 9, an additional power supply 10, parametric voltage regulator 11, which is connected with resistor I2 and zener diode 13, driver control driver 14, consisting of a single junction transistor 15, capacitor 16 and four limiting resistors 17-20, current generator 21 consisting of transistor 22 and three body resistors 23-25, capacitors 26 and 27, transistor 28 and diodes 29-31. The input of the additional power supply 10 is connected to the input pins, the output of the source 10 is connected to the input of the parametric voltage regulator 11, the output of the shaper 14 is connected to (With bushing electrodes of the valves 5 and 6. The input of the current generator 21 is connected to the capacitor 26 and the anode of the diode 30. The free plate of the capacitor 26 is connected to the cathode of the diode 29; the anode of the diode 29, the cathode of the diode 30 and the capacitor 27 are connected to the collector of the transistor 28, the free plate of the capacitor 27 is connected to the emitter of the transistor 28 and the anode of the diode 31. The base of the transistor 2 8 and the cathode of the diode 31 are connected to the positive output terminal 4. The device operates as follows: A single junction transistor 15 is used as a relay element in this converter. The voltage from the Zener diode 13 of the parametric stabilizer 11 is the supply voltage for the transistors 15, 22 and 28. When a single-phase mains voltage is applied to an additional power supply 10, the indirect voltage from its output goes to the input of the stabilizer 11. At the output of the parametric stabilizer 11, a voltage is generated rapetseidalnoy form CSD ,,, (Figure 2). This voltage is applied to the base of the transistor 15 through a resistor 18. The unijunction transistor (OPT) 15 opens when the voltage on its emitter reaches a switching threshold -. The emitter of the transistor 15 is supplied from the voltage of the capacitor 16. When the "voltage" is reached, the transistor 15 produces the formation of controlling them 3

pulson I ,, p, I enter, respectively, on the control of the electrodes of the valves (thyristors) 5 and 6.

Consider next the process of forming the voltage on the capacitor 1 6Uci6. The capacitor 16 begins to charge from the voltage from the output of the parametric stabilizer 1 1 - U, through the transistor 22 of the generator 21 t along the circuit: id, - capacitor 16 - resistor 24 - transistor 22 resistor 25 -. The constant charge time of the capacitor 16 varies depending on the current of the generator 21, which, in turn, is controlled by the voltage on the capacitor 26 - Uc-ij ,. At the initial moment, when the voltage on the Zener diode 13 - U ,, appears, the capacitor 26 and the capacitor 27 are charged by the front Udch. The constant component of the capacitors does not allow the capacitors to be absorbed. Since the value of capacitor 26 is much larger than the value of capacitor 27, the charge time constant of capacitor 26 is much larger than the charge time constant of capacitor 27. Therefore, while the voltage is on the capacitor 27 U (. for the half-period of the mains voltage increases to its maximum value, the voltage on the capacitor 26 - Ucjg increases only by a small amount. The charge of the capacitors 26 and 27 occurs along the circuit: VA. capacitor 26 - diode 30 - capacitor 27 - diode 31 Id, g. Next, when the Id decays, in the moment when the voltage Uc becomes greater than Ud, the positive potential from the capacitor 27 goes to the base of the transistor 28, it opens, and the capacitor 27 is discharged through the transistor 28. The capacitor 26 is discharged only by an insignificant value, smaller than the initial voltage value, to which the capacitor 26 charges, as the charge and discharge contours are not the same. Thus, by the beginning of the second half period, Uc26 has a certain value j, which determines the flow of current through the transistor 22.

Upon receipt of the negative half-wave of the mains voltage, it is flush with an additional power supply 10, and the rectified voltage is fed to the input of the stabilizer

7054

11, The process is repeated with the difference that the greater the Uc, the greater the base current of the transistor 22, the longer the capacitor 16 charges with a longer time, the faster Ucie reaches the id of the transistor 15, and a control pulse is generated lynp, therefore, the opening of the valve 5 or 6, With each half-period, the capacitor 26 is recharged by a small amount, applying to the base of transistor 22 an increasing current, the current of the transistor 22 smoothly changes, the charge current of the capacitor 16 smoothly changes, the control pulses smoothly shift smoothly shaped a voltage at the output DC converter vshr - Ug ,, x, hence, is carried smooth starting device.

Emergency modes in the starting current circuit of the rectifier are not possible.

Claims (1)

Invention Formula A variable-to-constant voltage converter containing a single-phase bridge rectifier, the cathode group of which, forming a positive output terminal, is filled to controlled valves, and the anodic group, forming a negative output terminal, on uncontrolled valves, a filter capacitor connected to the output terminals, an additional power source, an input connected to the input leads, formed by the diagonal of the alternating current of the bridge meter, and an output to a parametric voltage regulator input, a control pulse driver connected to the control circuit of the charging current by the input, and an output to the control electrodes of the controlled valves, the main diode and cond nsator, characterized In order to increase reliability by providing a smooth start, a current generator was introduced into the charging current control circuit, the input of which is connected to one plate of a circuit capacitor, the other plate of which is connected to the output of a parametric voltage regulator and the cathode of the main diode, an anode connected to a collector of an additionally inserted transistor and one lining of the main capacitor, the other lining of which is connected with the emitter of the same transistor and the anode of the first additionally inserted diode, the cathode connected to the positive output terminal, the collector of the transistor is also connected to 12757055 the cathode of the second additionally inserted diode, the anode of which is connected to the input of the current generator, and the base of the BXOnV PPUG-n-iTii-sT-, rr ,, transistor of the transistor is connected to a positive 5 OUTPUT pin.