SU1628127A1 - Voltage converter - Google Patents

Abstract

The invention relates to electrical engineering and can be used to power communication devices. The purpose of the invention is to increase reliability and enhance functionality by preventing false tripping of protection during transients in the network. The converter contains a key inverter 1 with a transformer and a rectifier 2 at the output and a current sensor 17 into a power circuit and a control circuit 14, a connection

Description

The invention relates to electrical engineering and can be used to power communication devices.

The purpose of the invention is to increase the reliability and expansion of functional capabilities, eliminating false triggering of protection during transients in the network.

Figure 1 shows the functional diagram of the invention, figure 2 shows the time diagrams of its operation.

The device contains an inverter 1,., Connected to the rectifier and filter., Load 3, resistor 4, transistor 5, the emitter of which is connected to the midpoint of the divider on the reporter 6, 7, transistor 8, transistor :), divider by resistors 10, 11, transistor 13. Collector 12

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the transistor 13 is connected to the blocking input of the control circuit 14, to the other inputs of which are connected the outputs of the master oscillator 15 and the comparator 16 and the reference source, a current sensor 17, a resistor 18.

The device works as follows.

The master oscillator 15 synchronizes the operation of the control circuit 14, which produces a modulated in duration control signals of the inverter 1. The voltage on the load is applied to the base of transistor 5. If there is an input voltage in the tolerance, the voltage on the base of transistor 5 is greater than on its emitter, the transistor is closed, while the transistor 8 is open and the emitter of transistor 5 contains a reference voltage removed from the divider on resistors 6, 7. The voltage pulses in normal operation on the current sensor 17 do not envelop Whether on state of the comparator 16 and consequently the control circuit 14 (Lig.2a).

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If the input voltage is normal and a fault has occurred in load 3 (short-circuit or overload on current is stable), the voltage on current sensor 17 increases and the comparator 16 every clock of the master oscillator 15 turns off the control circuit 14 until the output voltage The load in the load did not decrease to the threshold value set by the divider on the resistors 6, 7. At the same time, the transistor 5 opens and after charging the capacitor 12 through the resistor 6 (to increase noise immunity), the transistor 13 opens, blocking the control circuit 14 (FIG. ).

Claims (1)

If the input voltage is below normal, the voltage at the base of the transistor 9 becomes less than the reference voltage, the transistor 9 opens, the transistor 8 closes and the emitter voltage of the transistor 5 is absent, making it impossible for the transistor 13 to trip due to a decrease in the output voltage. When the input voltage is restored, the transistor 9 closes, the transistor 8 opens, and the device is ready for operation (Fig. 2b). Invention Formula A voltage converter containing a key inverter with a transformer and a rectifier at the output, a current sensor in the power circuit of the converter is connected, the output of which is connected to the comparator input, a control circuit with a blocking input, with a master oscillator connected to the first input and an output connected to the control input the inverter and the reference voltage source, which is based on the fact that, in order to increase reliability and enhance functionality by eliminating false triggering of protection during transient otsessah network, four tranzis51 introduced into it torus, two resistors and two resistive voltage dividers and a capacitor, the converter output being connected through the first resistor to the base of the first transistor, the emitter of which is connected to the output of the first splitter connected between the common bus and the collector of the second transistor connected to the emitter - the reference point, the base of the second transistor, and the collector of the third transistor are connected to the common bus through the second resistor, 76 the emitter of the third transistor is connected to the source of the reference voltage, and its base is connected to the output of the second voltage divider connected between the input voltage source and the common bus, the collector of the first transistor is connected to the base of the fourth transistor and simultaneously via a capacitor connected to the common bus, with which the blocking input of the control circuit is also connected via the power junction of the fourth transistor. B / but AT FIG. 2