SU783931A1 - High-frequency series inverter - Google Patents

Description

one

The invention relates to the field of electrical engineering and can be used in high-frequency electrothermal installations.

Known inverters containing counter-parallel thyristor diode pairs and oscillatory chains of V3 capacitors and chokes

. Their disadvantage is the low frequency of the ventilation.

The prototype of the invention is an inverter, which contains counter-parallel pairs of direct and reverse controlled valves, oscillatory circuits, ka, of which contains a capacitor and a choke, as well as a filter choke.

The disadvantage of the prototype is the need for an additional device, ensuring that the check valves are unlocked. In addition, an increase in the inversion frequency causes an increase in the steepness of the current front in both forward and reverse fans, which occurs due to a decrease in the inductance of the chokes of the oscillatory circuits. The purpose of the invention is to increase the inversion frequency, as well as to simplify the inverters.

 The goal is achieved by the fact that in a well-known inverter, the counter-parallel pair of direct and reverse controlled

5 valves, oscillatory circuits, each of which contains a capacitor and a choke, as well as active-capacitive dividers, each of which is connected in parallel to its pair of valves,

0 in series with each pair of valves is turned on and the throttle is. and the middle point of the active-capacitive divider, through a threshold element and a diode is connected to a control w with an electrode controlled by a reverse controlled valve.

Each active-capacitive divider shunting one of the counter-parallel valve pairs provides.

20 limiting the steepness of the front of the voltage rise on both the forward and reverse valves of this pair.

The divider, the threshold element, and the tensioning choke form a pick-up shaper for the non-return valve. The time delay of these pulses relative to the start of the voltage recovery at the non-return valve is determined by the values of active resistance and capacitance.

divider capacity, the voltage of the breakdown of the threshold element and the initial inductance of the saturation of the throttles. - During the delay, a negative restoring voltage defined by the voltage is applied to the forward valve; on the oscillator circuit capacitor. The saturable choke also serves to create an interval of insignificant steepness of current buildup through the forward and backward valves when they are unlocked, equal to the remagnetization time.

hearth, as well as to reduce the steepness of the front of the rise of the direct load. on each of them. The residual inductance of the throttle may be: 5 5b in the quality of the inductance of the throttle of the oscillatory circuit.

Figure 1 is an electrical inverter circuit (option); in fig. The Diagrams, which show the operation of the circuit in FIG.

{the inverter contains a parallel-parallel pair of direct 1 and reverse 2 thyristors, an oscillatory circuit containing a capacitor 3, a choke 4, and a load 5. Consistently with the valve pair is connected a saturable choke b. A pair of shunt divider from tank 7 and active

, resistance 8. The middle point of the split-tree is connected via an oppositely-connected diode 9 and a phase diode 10. The inverter is powered from the source of the single voltage through the filter choke 11.

The scheme works as follows. Suppose that at the moment of supplying the control pulse to the thyristor 1, the condenser ator 3 is charged with the polarity shown in Fig. 1. When the thyristor is unlocked along the circuit, the elementary 3, 6, 1, 5, 4 oscillating current of the capacitor 3 flows, and Thanks to the presence of a saturated drosse l, it is formed at the initial moment. does it mean that to Nyrga is a current camp whose duration is

 in: reshore nipwarHiiWHeaHHH heart of the heart of the drossel. At the moment of termination of the first half-wave of the discharging current, the thyristor 1 goes out, and the voltage on the capacitor 3 is full; , reverse shown in figure 1. This voltage causes the setting of the reverse for the thyristor 1 and the voltage for the tlristor 2 voltage: The CKSptfcTb valve pair of increase; this voltage (limited by the active-capacitive RSLtey1) L and the throttle 6. In this process, a capacitor is charged along the contour of the elements 3, 4, 5 ,, 8, 7, b. When the voltage on the capacitor 7 is equal to the voltage of the breakdown avalanche diode 10, the latter breaks through, which is accompanied by an impulse of TOK on the control electrode of the thyristor 2, which, when unlocked, discharges the capacitor 7

783531

along the contour of the elements 7, 8, 2. At the same time, the reverse half-wave of the oscillating current begins to flow through the thyristor 2, which, like the first, has an interval of a slight increase in current, which is also formed due to the presence of throttles b. At the end of the flow of the reverse-wave, the thyristor 2 is closed, after which the charging of the capacitor 3 with the input current along the circuit of 11,3,4,5 begins. When the next control pulse is applied to the thyristor 1, all processes are repeated.

Figure 2 shows the timing diagrams of the control pulses.

thyristor 1, current i thyristor 1, current,; thyristor 2, as well as the voltage on the valve pair.

The application of the invention will simplify and make cheaper high-frequency power source.

due to the exclusion of an additional control device, on the other hand, the invention makes it possible to increase the frequency inverted by 20% JO. In addition, the invention permits the use of less deficient ones. . Ventilators with a long (30–40%) recovery time and a lower (30–40%) allowable rate of increase in time.

invention formula

High frequency sequential

an inverter containing counter-parallel pairs of direct and reverse controlled valves, oscillatory circuits, each of which contains a capacitor and a choke, as well as active-capacitive dividers, or each

of which are connected in parallel to their own pair of gates, so that in order to increase the frequency, to invert and simplify, a saturated throttle is connected in series with each pair of gates, and the middle point of the active capacitor divider through the threshold the element and the diode are connected to the control electrode of the reverse controlled power.

Sources of information taken into account in the examination

1. Thyristorzh. - Technical reference. Ed. V. A. Labuntsova and others. M., Energie, 1971, p. 175,224227.

2. Gitgarts D. A., Ioffe Yu. S. New sources and power supply and automation of induction installations for heating and melting. M., Energie, 1972, p. 69-71. . -,

3. Akodis MM, Dr. V. V. Powerful thyristor transducer of ultrasonic frequency. - Abstracts of the report-,

Dov Scientific and Technical Conference

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Development and production of frequency b in mechanical engineering. M., the semiconductor converter transducer, 1977, p. 40

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Claims (1)

Claim A high-frequency serial inverter containing counter-parallel pairs of direct and reverse controlled valves, oscillating circuits, each of which contains a capacitor and inductor, as well as active-capacitive dividers, each of which is connected in parallel to its own pair of valves. in order to increase the frequency of inversion and simplification, a saturable inductor is connected in series with each pair of valves, and the midpoint of the active-capacitor divider is connected to the control via a threshold element and a diode yayuschim electrode reverse manageable »$ q th gate.