SU1150714A1 - Device for controlling a.c. voltage-to-d.c. voltage converter - Google Patents

Abstract

A DEVICE FOR CONTROLLING A VOLTAGE VOLTAGE VOLTAGE CONVERTER with an intermediate link of the frequency in the form of a single-phase polzzhestvoi thyristor inverter, containing a set of fixtures, and a set of fixtures. the output of the converter, the reader, the output is connected to the control input of the pulse generator, the output of the generator is connected to the counting input t the trigger, the outputs of the trigger are connected to the inputs of the control pulse formers, the outputs of which are intended to be connected to the control electrodes of the inverter thyristors, characterized in that, in order to increase the reliability and improve the mass and dimensional parameters, it is equipped with an amplifier-limiter, a voltage stabilizer with a current latch input and a differentiating RC circuit, connected to each other by the output of the stabilizer and the input of its current latch, moreover (L, the output of the stabilizer is connected to the power supply circuit of the pulse generator, and the amplifier-limiter is connected between the output of the pulse generator and the counting input of the trigger. ". /

Description

11 The invention relates to electrical engineering and can be used to control alternating voltage converters in a constant with an intermediate level increased frequency. A device for controlling an alternating voltage converter into a constant with an intermediate Hbw link of the frequency frequency in the form of an inverter is known, comprising a series-connected threshold element, a controlled oscillator, a trigger with a counting input, and control pulse shapers. The feedback signal from the output of the converter is fed to the input of the threshold element, which ensures frequency stabilization of the output voltage of the converter lj. The disadvantage of the device is the possibility of inverting the inverter during start. The closest to the invention is a device for controlling an alternating voltage transducer into a constant with an intermediate link of increased frequency. In the form of a single-phase half-bridge thyristor inverter containing a series-connected threshold element, a variable-frequency pulse generator with a control input, a trigger with a counting input and control pulse shapers, and the generator is equipped with an additional capacitor 1 connected to the main time by a master capacitor via contacts p barely, and its winding is turned on to the rectifier output iz. In such a device, when turned on, the generator operates at a low frequency, resulting in a stable start of the inverter. When the output voltage reaches the threshold value, the relay disconnects the additional capacitor and the control unit operates at the nominal frequency ensuring the nominal power of the rectifier. The disadvantage of the device is low reliability due to the presence of a contact device. The discrete change in frequency leads to the fact that as a result of the transition process, the pause between inverter pulses is reduced and, in order to prevent the inverter from tipping over, the pause is needed2 to be increased by 20-30%, and this leads to an increase in the mass and volume of the rectifier elements. invention - improving the reliability and improving the mass and size indicators of the rectifier. This goal is achieved by the fact that a device for controlling an alternating voltage into constant-frequency converter with an intermediate link of increased frequency in the form of a single-phase half-bridge thyristor inverter, containing a threshold element, a variable-frequency pulse generator with control input, a trigger with a counting input, and a control pulse generator, the input of the threshold element is intended for connection to the output of the converter, the output is connected to the control input of the pulse generator, the output is generator It is connected to the counting trigger input, the trigger outputs are connected to the control pulse shaper inputs, the outputs of which are intended to be connected to the control electrodes of the inverter thyristors, equipped with a limiting amplifier, a voltage stabilizer with a current latch input and a differentiating KS circuit included between the output of the stabilizer and the input of its current latch, with the output of the stabilizer connected to the power supply circuit of the pulse generator, and the amplifier-limiter is connected between the output of the pulse generator and the circuit trigger input. Figure 1 presents the scheme of the device; Fig. 2 shows voltage plots on device elements. A rectifier control unit with a transformerless input includes an input terminal 1, a thyristor serial inverter 2, an output rectifier 3, a threshold element 4, whose input is connected to the rectifier 3, and an output to a pulse generator 5. To the output of the generator 5 through a limiting amplifier & and the trigger 7 is connected to the control pulse formers 8 and 9, the thyristors of the inverter 2. Between the output of the auxiliary source 10 and the generator input. 5, a stabilizer 11 is turned on. The generator 5 consists of a transistor 12 used as a variable resistance, the time of setting the capacitor 13 and

311507

resistance 14, operational amplifier 15, assembled on a 140UD 1A microcircuit. A stabilizer 11 is assembled on a chip 142EN2B (16). A differentiating chain consisting of a capacitor 17 and a resistance 18 is connected between the output of the stabilizer 11 and the input s of the current latch.

The device works as follows.10

When the rectifier is turned on, the voltage at the output of the stabilizer 11 begins to increase smoothly (Fig. 2a), and the growth rate is determined by the time constant of the RC chain 15 17 and 18. With a smooth increase in voltage at the input of the generator 5, its frequency smoothly increases ( figb).

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Amplifier-limiter 6. Amplifies and limits (Fig. 2c) the generator 5 pulses, varying in wide limits in amplitude, which ensures reliable switching of the trigger 7 (Fig. 2d). A smooth change in the frequency of the control thyristor pulses (Fig. 2 d, e) ensures a reliable start of a series inverter loaded on a rectifier.

The application of the proposed device makes it possible to calculate the steady-state operating modes of a series inverter with a minimum pause between pulses, which improves the mass and size characteristics of the rectifier, and the exclusion of contact elements increases its reliability.

Claims (1)

DEVICE FOR CONTROLLING A VARIABLE VOLTAGE CONVERTER TO A CONSTANT with an intermediate link of increased frequency in the form of a single-phase half-bridge thyristor inverter containing a threshold element, an adjustable frequency pulse generator with a control input, a trigger with a counting input and a pulse pulse shaper for connecting the element to the control pulse output, moreover converter, the output is connected to the control input of the pulse generator, the output of the generator is connected to the counting input of the trigger, in the trigger outputs are connected to the inputs of the control pulse shapers, the outputs of which are designed to connect to the control electrodes of the inverter thyristors, characterized in that, in order to increase reliability and improve overall dimensions, it is equipped with an amplifier-limiter, a voltage regulator with an input of the current latch and a differentiating RC- flails, _Λ included chennoy mrzhdu stabilizer 3 output and the input of its Tokovaya latch, wherein the stabilizer is included in the output of the pulse generator power supply circuit, a power-Res nichitel connected between the output of the generator impulsov.i counting input of the flip-flop. SU. ,,,> 1150714 ♦ 1150714