SU247391A1 - HIGH FREQUENCY ALL-UNIT CONVERTER4 - Google Patents

Description

The described invention is an improved version of the increased frequency converter according to the basic author. St. No. 99555.

The difference between the proposed converter is that the end of the choke is connected to one of the electrodes of the controlled valve through an auxiliary diode connected to one of the capacitor plates, which is connected to the other end of the choke switches through the serial line of the resistor and the other plate of the capacitor through the other resistor connected to another electrode of a controlled valve. As a result, the reliability and efficiency of the converter is increased when executing with co-integrated gates, including anti-parallel-controlled gates, and its energy performance is improved.

FIG. 1 is a circuit diagram of a high frequency converter; in fig. 2 is a variant of the circuit design of the same device.

The device contains filter capacitors I, 2, oscillating circuit capacitor 3, inductance of oscillating circuit 4, load 5, chokes 6, 7, controllable working valves 8, 9, uncontrolled reverse diodes (gates) W, 11, shunt capacitors 12, 13 , charging resistors 14, 15 are shunted, circuits to it, discharge resistors 16, 17 are shuntted, circuits to it, diodes (gates) in charge circuit 18, 19, diodes (gates) in discharge circuit 20, 21.

In converters with counter-parallel switching of valves 8 10 (9 to 11), the throttles 5 and 7, the gates 18, 19 (bypass circuit) prevent excessive growth rate, which limits the initial amplitude of the reverse voltage on the valve. x countercurrent is direct for controlled direct current valves. In this case, the capacitor 12 (13) of the shunt circuit is charged to a voltage equal to the amplitude of the direct voltage on the controlled valve.

In order for the capacitor to sufficiently effectively protect against excessive voltage buildup and overvoltages on the valves with acceptable saturation, his throttle, in series with the capacitor, only a small resistance can be switched on. In this case, when the converter is executed on semiconductor valves (thyristors), the capacitor must be connected through a low-power diode 18 (19) so that at the moment of switching on the next controlled valve it does not create a significant initial amplitude of the discharge current dangerous for the valve. Connecting a capacitor shunt the main valves through a diode

requires the creation of an additional circuit to discharge the capacitor during the passage of current by the main valves. At significant output frequencies, in order to discharge the capacitor shunt valves before the next charge of its current after current interruption in the oncoming diode, it is necessary to ensure discharge through a relatively low resistance. For this purpose, a low-power diode 20 (21 ). As a result, capacitors directly bypass the main valves only when voltage is restored to them. The reverse discharge of the capacitor is not transmitted directly to the valves, which excludes the occurrence of significant initial currents s valves. In this case, the magnitude of the charging resistor 14 (15) is selected from the condition of optimal damping of oscillations of the voltage that is restored on the valves to limit the overvoltage on them and the rate of its rise.

The magnitude of the discharge resistance 16 (17) is selected to be optimal for the discharge of the capacitor 12 (13) of the shunt circuit during the operation of the controlled direct and uncontrolled check valves 8, 10 (9, 11) of the circuit.

Subject invention

Converter high frequency main auth. St. No. 99555, different

the fact that, in order to increase reliability and efficiency of the converter when it is performed with counter-valves, which are turned on by anti-parallel-controlled valves, the end of the choke is connected to one of the electrodes

controlled valve through an auxiliary diode connected to one of the capacitor plates, which through a series of resistor and diode connected to the other end of the throttle, and the other capacitor plate through another resistor connected to the other electrode of the controlled valve.

4-; ya