SU1171920A1 - Control unit of voltage converter - Google Patents

Abstract

1. A CONTROLLER UNIT OF A VOLTAGE TRANSMITTER containing a paraphase switch, with which a current limiting element is connected in series, and a sawtooth driver, controlled by short pulses, characterized in that, in order to increase efficiency, the control input of the former is connected through a resistor to a thermograder. . 2. The unit according to claim I, characterized in that a choke is used as a current limiting element. 3. The unit according to claim 1, characterized in that a resistive current sensor is used as a current-limiting element.

Description

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The invention relates to electrical engineering and can be used in secondary power supply systems.

The purpose of the invention is to increase efficiency.

FIG. 1 is a schematic diagram of a device with a push-pull transistor switch, FIG. 2 - the same, with a single-ended transistor switch; in fig. 3 - device with push-pull transistor switch, option; in fig. 4 - the same, with a single-ended transistor switch (option).

The control unit (Fig. 1) contains an input voltage switching node 1, whose transistors 2 and 3 and current limiting element 4 form a series circuit connected to the power supply circuit. The terminals of the current-limiting element are connected through a resistor 5 to the control input of the sawtooth voltage former 6.

In low-power devices, it is preferable to use a resistor as a current-limiting element (Fig. 4), and in those cases when an electrical isolation of the input and output is required, a two-winding choke (Fig. 3) is required.

The device works as follows.

During the operation of the device, each time the key element 2 is turned on, the second key element 3, which is turned on at this moment, does not turn off instantly.

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and with some delay in time, due to its inertia.

Since, at the same time, the resistance of simultaneously connected key elements 2 and 3 is small, the entire voltage of the power source is applied to the element 4, which limits the amount of the overlap current ("through current).

The delay time for switching off transistors and diodes is a few microseconds and determines the duration of the pulse formed on the terminals of the limiting element 4. Its duration and amplitude are sufficient to control, for example, a sawtooth generator, synchronized by the generator.

A resistor 5 is turned on to reduce the shunt effect of the driver input. To provide galvanic isolation of the input and output and reduce losses

0, the power restrictive choke can be made double-winding (with an additional winding 7 shown in FIG. 3). In comparison with the known, in which for the formation of narrow pulses, synchronous with the operation of the device, are used

two differentiating chains with a full-wave rectifier, the proposed device does not require an additional driver and, therefore, has a higher efficiency.

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Claims (3)

1. CONTROL UNIT OF A VOLTAGE CONVERTER containing a paraphase switch, a current limiting element is connected in series, and a sawtooth voltage shaper controlled by short pulses, characterized in that, in order to increase the efficiency, the shaper control input is connected through the resistor to the terminals of the current limiting element. 2. Block by π. 1, characterized in that a choke is used as a current-limiting element. 3. Block by π. 1, characterized in that a resistive current sensor is used as a current-limiting element. > FIG. 1