RU1818668C - Ac-to-dc voltage converter - Google Patents

Abstract

Usage: AC to DC conversion for secondary power systems and automation A. The inventive capacitive filter at the output of the network rectifier 1 is made on six capacitors 2, 4, 7, 8, 9, 10. For a certain period of time in the middle of the half-cycle, the load is powered directly from the network, and the capacitors are charged in a three-volt series connection. two chains, namely 2-8-4 and 9-7-10. In the remaining intervals of the half-cycle, when the input voltage of the network decreases, the diodes of the rectifier 1 are closed and the capacitors in the parallel connection are discharged to the load. 1 s P. f-ly, 2 ill.

Description

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The invention relates to the field of electrical engineering and can be used as a source of secondary power for electronic devices.

The aim of the invention is to reduce the weight and dimensions when working on a single load and increase the manufacturability.

In FIG. 1.2 is a diagram of the device and diagrams of currents and voltages of the invention, where:

1 - input single-phase bridge rectifier;

2 - the first capacitor;

3 - the first diode; . 4 - second capacitor;

5-6 - respectively, the first and second chains;

7,8,9,10 - respectively the third, fourth, fifth, sixth capacitors;

ui, And - respectively, the mains voltage and mains current;

ic is the capacitor current;

uC2, uC4, Uc7, uC8, uC9, Ucio - respectively, the HO voltage at the first, second, .. ,, sixth capacitors;

UAB - voltage at the device output;

t is the current time coordinate.

To carry out the described invention, an AC / DC converter is provided, consisting of: an input single-phase bridge rectifier 1, six capacitors 2, 4, 7, 8, 9, 10, diode 3 and two circuits 5 and 6, each of which contains two diodes in series.

The mains voltage Ui is rectified in the input single-phase bridge rectifier 1 and supplied to the capacitors in two circuits: the first circuit: - point A, the first capacitor 2, the fourth capacitor 8, the second circuit 6, the second capacitor 4 and point B; the second circuit is point A, the fifth capacitor 9, the first chain 5, the third and sixth capacitors 7 and 10 connected in series, respectively, point B. All capacitors are made of the same type (of the same type), so each capacitor is charged the same to the voltage Uim / З where Uim is the amplitude value of the mains voltage (when charging, three capacitors in the circuit are connected in series, as it were).

The capacitors are discharged in three circuits: the first circuit is point B, the second capacitor 4, the first diode 3, the first capacitor 2, point A; the second circuit is point B, the second chain 6, the fourth capacitor 8, the fifth capacitor 9, point A; the third circuit is point B, the sixth capacitor 10, the third capacitor 7, the first chain 5, point A. When discharging, two capacitors in each discharge circuit are connected as if in series. Therefore, the discharge voltage of the equivalent capacity of the device is

Up 2Ulm / 3.

In the time interval, the load connected to the output of the inverter

At a constant voltage, the capacitors are charged from the mains to Uim / 3, and in the time interval ti-ts the current stops from the mains as the capacitors begin to discharge to the load. Moment 5 ti and t. 4 are determined by the formulas:

12 1 2 ti arcslibj; (n-arcsing).

As can be seen from the diagram (Fig. 2d), the interval of the current flowing through the network increases, its peak value decreases, the effective value of the mains current decreases, which causes an increase in the power factor of the device.

Capacitor Discharge Time

5 is reduced in comparison with known circuits, which makes it possible to reduce the capacitance of capacitors. The equivalent capacitance of the converter is C 3C0 / 2, where Co is the capacitance of one capacitor, Em0, the bone Co is selected depending on the load.

The advantage of the proposed technical solution is the ability to operate the circuit on a single load, which

5 is achieved in the known device due to significant complications of the circuit. Therefore, the proposed device allows to reduce the mass and dimensions of the Converter when working on one load.

0 in order to increase the technological production of the converter by reducing the range of elements used (unification), capacitors of the same type were selected,

Claims (2)

5 in another embodiment. It is possible to select both the fourth and second capacitors each with a capacitance, replace the first and fifth capacitors with one equivalent to the capacitance, and replace the serial connection of the third and sixth capacitors with an equivalent one. SUMMARY OF THE INVENTION 1. A dc-to-dc converter comprising an input 5-phase bridge rectifier connected by an output to the output terminals of the converter, the first of which is connected to the first terminal of the first capacitor, the second terminal of which is connected to the first terminal through the first diode a second capacitor connected by a second terminal to a second output terminal of the converter, the first diode being connected in the direction of conductivity that is opposite to the polarity of the output voltage of the converter, characterized in that, in order to reduce weight and dimensions when operating on a single load, introduced the third and fourth capacitors and two identical circuits, each of which consists of two diodes in series, the first circuit connected in parallel with the first capacitor, and the second pa Allelic second capacitor with the direction of conduction diodes chains, consonant with the direction of conduction of the first diode, the average sharpening № Ts U-tt Mi Urp ce cgVUcjo 6 3 Compiled by A. Gomisoni i $ 112.2 Editor A. Kolda Tehred M. Morgenthal Corrector Ю.USCO, Order 1940 VNIIIPI of the State Committee for Inventions and Discoveries under the USSR SCST 113035, Moscow. Zh-35, Rauska embankment. 4/5 the first chain through the third capacitor circuit is connected to the second input terminal of the converter, and the midpoint of the second chain through the fourth capacitor is connected to the second terminal of the first capacitor. 2. The converter according to claim 1, characterized in that, in order to increase the manufacturability by reducing the range of elements used, the fifth and sixth capacitors are introduced and all capacitors are made of the same type, with the fifth capacitor connected in parallel with the first capacitor and the sixth capacitor turned on sequentially in the circuit of the third capacitor. T