RU1798868C - Method of phase shift of rectangular voltage for control over rectifier converter - Google Patents

Abstract

The invention relates to electrical engineering, in particular to converter technology, and can be used in the development of pulse-phase control systems, for example, rectifiers, inverters, converters with an increased frequency link. An object of the invention is to expand the scope of use by allowing for smooth adjustment of the phase shift of the output voltage. The method of phase shift of the output voltage is that the reference and output rectangular voltages are divided in frequency, the phases of the received signals are compared and a rectangular voltage of doubled frequency is generated, the duty cycle of which is inversely proportional to the phase difference of the mentioned voltages. The frequency of the output voltage is set in direct proportion to the constant component of the rectangular voltage at twice the frequency. Unlike the known method, the frequency of the reference and output voltages is divided by the same amount, and the constant component of the rectangular voltage of twice the frequency is controlled in magnitude. The method allows a phase shift of up to 180 e. grad., which allows its use in SIFU converters of various types. 2 ill. ate with

Description

The proposed technical solution relates to the field of pulse technology and can be used in the construction of pulse-phase control systems for rectifiers, inverters, discrete voltage shapers, converters with summing of output voltages with a high frequency link and other devices ..

The aim of the invention is to expand the scope of the known method by providing

the possibility of smooth adjustment over a wide range of phase shift, between rectangular reference and output voltages.

In FIG. 1 shows a block diagram of a device that implements the method: in FIG. 2 - diagrams of signals explaining its operation, where:

a) reference voltage;

b) a reference voltage with a frequency divided by 8;

c) output voltage with a frequency divided by 8:

vj

H) 00 WITH

about

00

d) output voltage;

e), g), h) the signals at the output of the phase detector and their constants in the process of adjusting the phase shift.

A device that implements the proposed method contains a series-connected source of rectangular voltage (IPN) 1, a first frequency divider by 8 (PM) 2, a phase detector (PD) 3, a low-pass filter (LPF) 4, a voltage regulator (PH) 5, voltage controlled oscillator, (VCO) 6. The output of the latter is the output of the device, and is connected via a second frequency divider by 8 PM7 to the second input of the phase detector.

During operation of the device, which is a phase locked loop (PLL), synchronization of rectangular voltages at the inputs of the PDZ is ensured so that the voltage at the second input of the PDZ is behind the voltage at its first input by an angle of / 4 (Fig. , 2.6, c). In this case, the phases of the reference (Fig. 2, a) and the output voltages (Fig. 2, d) coincide, the voltage at the output of the DCF has a double frequency with respect to the input and the duty cycle equal to 0.5 (Fig. 2, d) , the constant voltage before the output of the low-pass filter is equal to half the voltage of the power source (Fig. 2e), and the transfer coefficient of the pH 5 is unity. If, with the help of the PH, one tries to increase the voltage coming from the low-pass filter 4, for example, by half, the situation in the PLL will change as follows; since the PLL system does not go beyond the frequency confinement range, the frequency of the rectangular output voltage of the VCO will not change, i.e., the constant voltage at the input of the VCO 6 will not change, which means a halving of the voltage at the input of the pH 5 or the same decrease in the duty cycle of the signals at the output of the PD 3 (Fig. 2, e), and, consequently, a decrease in the phase shift between the voltages at the input of the PD 3 by an angle of / 4 (Fig. 2, c - to the left arrow). The phase shift of the voltage ia the output of the second PM, 7 in the direction of advance by the angle l: / 4 {Fig. 2c) corresponds to a shift of the output voltage relative to the reference voltage by an angle of 2 (Fig. 2, d. If you try to reduce the voltage coming from the low-pass filter 4 using PH 5, the PLL system, maintaining the frequency often unchanged in the circuit, will respond accordingly a shift in the direction of lagging in phase voltage at the second input of PD 3

(Fig. 2, B - to the right arrow) so as to increase the duty cycle of the signal at the output of the photodynamic protective device (Fig. 2, g), i.e. constant voltage at the output of the low-pass filter 4, and keep unchanged

VCO input voltage 6. As shown in FIG. 2, with a full phase shift of the voltage at the input of the PDD by an angle of / 2, the output voltage is shifted relative to the reference by an angle of 4. Therefore cheating

the transmission coefficient of the voltage regulator and selecting the appropriate frequency dividers, it is possible to ensure a smooth change in the phase shift between the reference and output rectangular voltages within the required limits.

The proposed method allows to create a simple and reliable phase-shifting device that provides a phase shift of up to 180 el. hail, without the risk of disruption of generation, which can be widely used in SIFU for various power converters. In addition, the possibility of obtaining large phase shifts by the proposed method allows the design of simple and reliable devices for various delay circuits, frequency converters, etc. Therefore, the scope of the known prototype method is significantly expanded. : ..:.:; :.;,;. .- Formula A of the invention A method for shifting a phase voltage of a rectangular voltage for controlling valve converters, the method comprising:

that the reference and output rectangular voltages are divided in frequency, the phases of the received signals are compared, a doubled frequency voltage is formed, the duty cycle of which is inversely proportional to the phase difference of the mentioned voltages, and a constant component of the doubled frequency rectangular voltage is extracted, moreover, the frequency of the output rectangular NEP

directly proportional to the constant component of the rectangular voltage doubled frequency, characterized in that, in order to expand the scope of use by providing the possibility of smooth regulation within a wide phase shift between the reference and output voltages, the frequency of the reference and output voltage divisions t by the same amount, and the constant component

The double voltage rectangular voltage is adjusted in magnitude.

Figure 1

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FIG. 2

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