SU624345A1 - Single-phase inverter - Google Patents

Description

The invention relates to the field of converter technology and can be used in electro-automatic and electric drive systems for converting direct voltage to alternating single-phase voltage with a two-stage curve.

Single-phase inverters with a two-step output voltage curve are known, containing two power amplifiers, two master oscillators, and a phase-shifting unit that provides a phase shift between the generator voltages of 45 al-degrees. i. The disadvantages of such inverters are the complexity of the power circuit and the need for complex circuit design of the phase-shifting unit to ensure a stable phase shift.

A single-phase inverter with a two-step output voltage waveform is also known, which contains a power amplifier with an output transformer having leads from intermediate points of the primary winding, and a digital type control circuit consisting of frequency dividers per meter and four matching logic circuits, and so on. n. r2j.

The aim of the invention is to simplify the circuits of the inverter. This is achieved by hem that in the proposed inverter containing a power amplifier with an output transformer, the primary winding of which has intermediate taps, and power transistors connecting the extreme leads and intermediate taps of the primary winding of the output transformer to the output supply terminals, the direct and inverse outputs of the master oscillator are connected with the inputs of the frequency dividers by two and four, the frequency divider by two is connected to the first input of the coincidence circuit, the output of the four dividers to the second input to it coincidence with the control circuit of power transistors connected to the extreme terminals of the output transformer primary winding, and the outputs of the coincidence circuits -soedineny with power control circuit transistors podklyuchen362 GOVERNMENTAL omotki is primary taps to the output transformer, Fig. 1 is given the structural scheme of the described inverter; in fig. 2, a – z - anagrams of stresses on the main ones: circuit sections. The inverter contains master oscillator 1, divider 2 frequencies into two (flip-flop), divider 3 frequencies into four (two series-connected flip-flops 2) logic circuits 4 coincidence, power transistors 5-8 connecting the extreme leads (via diodes 9 and 10) and taps primary winding of the output transformer 11 -K INPUT; to shtyam: to conclusions of the Ch - and - the inverter. The inverter works as follows. With the output of the master oscillator 1, which generates pulses with a duty cycle of two (see Fig. 2, a), the signals arrive at trigger 2 and divider 3 parts. The voltage diagrams in FIG. 2, bd illustrate the operation of the trigger frequency divider, and the voltage in FIG. 2, d the voltage at the output of the trigger 2. The impulses from the trigger divider 3 frequencies (see Fig. 2, c, d) and the trigger 2 (see 4ig. 2, a) are fed to the inputs of the coincidence circuit 4, at the outputs the pulses driving the transistors 6 and 7 shown in fig. 2, hedgehog The pulses from the output of the 3 frequency divider control the power transistors 5 and 8. With the transistor 5 or 8 open, the transformation ratio of the transformer 11 is determined by the ratio. When transistor 6 or 7 is opened, the transformation ratio jumps to W2 / W. As a result, a step voltage is formed in the secondary winding of the transformer (see Fig. 2, g). The height of the mortar is determined by the ratio of turns.

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Claims (2)

Jn 5 the primary winding of the transformer W J and its part W. As. -Q, 4f, the content of the 3rd and 5th harmonics is minimized, while the width of the step 45 is maintained automatically and equal to the half-period of the oscillator frequency. Formula of the br | 1eteny Single-phase inverter with a two-step output voltage curve containing (interconnected power amplifier with output transformer; torus, the primary winding of which has intermediate taps, and power transistors connecting the extreme terminals and intermediate taps of the primary winding an output transformer with output supply terminals, a master oscillator, a frequency divider by two, a frequency divider by four, and a matching logic circuit, characterized in that, in order to simplify direct j, the inverse outputs of the master oscillator are connected to the input of a frequency divider by two and a frequency divider by four, respectively, the output of the frequency divider by two is connected to the first input of the coincidence circuit, the output of the frequency divider by four is connected to the second input of the coincidence circuit and the control circuit of the power transistors connected to the extreme terminals of the primary winding of the output transformer, and the outputs of the circuits of coincidence with the control circuit of the power transformers connected to the taps of the primary winding of the output transformer. Sources of information taken into account in the examination: 1.Certificate of certificate №139722, cl. H O2 M 5/22,1960. 2. US patent number 3241038, cl. 321-44, 1966.