SU634434A1 - Self-sustained series inverter - Google Patents

Description

one

The invention relates to DC-to-AC converters and can be applied to high-frequency power supplies for induction installations.

In circuits of known autonomous serial inverters containing two groups separated by filter droplets, pairwise and serially connected via switching throttles of valve bridges, two filter capacitors, between the extreme terminals of which the load is turned on, the voltage on the circuit elements is limited to the sum of the supply voltage voltage and load.

The aim of the invention is to increase the effectiveness of voltage limiting on the inverter elements.

This is achieved by the fact that, in the proposed Inverter, other power electrodes of the reverse diodes of other antiphase branches of the valve bridges are connected to opposite output terminals and to the plates of filter capacitors associated with the negative terminal for the power supply.

The drawing shows the scheme of the proposed inverter.

It contains controllable valves 1-32, commanding capacitors 33-40, switching inductors 41-44, reverse diodes 45-52, filter capacitors 53-56, filter inductors 57-60, load 61.

The inverter works as follows.

In the first cycle, the groups of valves 1–4 and 9–12 are turned on and the current pulse, which is close to sinusoidal in shape, flows along the following circuits: 61–53–1–33– 2–41–3–34–4–56–61 and 61-53-9-35-10-42-11-36-12-56-61, creating at the load 6 a voltage drop of the polarity indicated on the drawing. When the voltages on the inductances 41 and 42 take the polarity indicated in the drawing, and the magnitude of each of them is greater, the sum of the half voltage of the power supply and the load voltage,. Diodes 45, 46 and 47, 48 are turned on, and the energy return current flows through the following circuits: 61-47-42-48-54-61 and 61-55-45-41-46-61, creating a voltage drop across the load polarity, thu and current bridges. At the same time, the current through the mos. Quickly ceases, and the voltage

the switching elements are limited by 1/1 in magnitude. The energy stored in the throttles x 41 and 42, is consumed in the load, and also goes to the charging of capacitors 54 and (55.

In the second cycle, valves 17–20 and 25–28 turn on and currents flow along the chains: 61-54-17-37-18-43-19-38-20-55-61 and 61-54-25-39-26 -44-27-40-28-55-61.

The currents return energy chokes 43 and 44 flow through the chains 61-49-43- -50-53-61 and 61-56-51-44-52-61. The currents of bridges and the currents of energy return create a voltage drop on the load, the polarity of which is opposite to the polarity of the voltage in the first cycle

In the third cycle, valves 5–8 and 13–16 turn on and currents flow along the chains: 61-53-5-33-6-41-7-34-861-53-- 3-35- 14--42-15 -36-56-61

and

-16-56-61; Energy is returned to the load and to the filter capacitors by the same circuits as in the first cycle.

In the fourth cycle, valves 21-24 and 29-32 are turned on and current flows through the circuits: 61--54-21-37-22-43-23-38-24-55-61 and 61-54-29-39- 30-44-31-40-32-55-61. The circuits of energy return currents are the same as in the second cycle.

Thus, HMiiyjibCbi of alternating polarity current, which is close to the sinusoidal form, flows through the load.

The circuit can work in the eight-stroke mode. For this, the first tact includes 1-1 or 1–4, in the second - 25–2, in the third 9–12, in the fourth - 17–20, in the fifth 5–8, in the sixth - 29–32, 13-16, in the eighth - 21-24. In this case, the 7deg1 5 current flows are preserved. Eight-bit mode allows you to increase the output frequency of the circuit.

Limiting the voltage at the switching inductance at the level of half the supply voltage reduces the voltage on all the elements of the circuit and makes them low dependent on the voltage on the load, which allows the use of lower-grade thyristors and i:.: -: whole

Claims (1)

Invention Formula A sequential autonomous Inzertor containing two antiphase valve converters, each of the x and tornh consists of two parallel Ee wei formed by two series connected valve assemblies through two electrolytic chokes, two groups consisting of two series-connected condensate filters ::. connected to the terminals for power supply through the filter chokes, the output terminals of which are connected by the serial points of the series connection of the filter capacitor OE, and the common point of the serial connection of the valve bridges and the 1-p:; from az-; left electrodes of the reverse diodes, other power electrodes of the reverse diol :.:- :: two antiphase branches of ventilg, kzh ;; bridges connected; to the output of the filter, which is connected with a positive output for the power source, o. j: this is because, in order to increase the efficiency of the voltage limiting voltage on the elements of the inverter, others The power electrodes of the reverse diodes of the other antiphase branches of the valve bridges are connected to the OPPOSITE output terminal and to the plates of the filter capacitors connected to the negative terminal for the power supply.