SU122200A1 - Device for periodically changing the polarity of a dc generator - Google Patents

Description

The present invention relates to devices for periodically changing the polarity of a direct current generator supplying a galvanic bath by changing the direction of the excitation current of the generator driver.

The proposed device differs from the known ones in that it is made according to the scheme of an asymmetric multivibrator containing two controlled thyratrons, between the anodes of which the excitation winding of the generator exciter is turned on.

Such an embodiment of the device allows the frequency and voltage ratio to be smoothly controlled.

The drawing shows prnniiia.m on the scheme of the proposed device.

The device consists of a multivibrator on IT and 2T tiratrons, between the anodes of which the excitation winding of the OVV exciter B is turned on. The latter supplies power to the excitation winding of the AVG.

The power of the anode circuits of the thyratrons is carried out from a direct current source (selenium rectifier). The heating circuit is powered by a separate transformer, not shown in the drawing.

The proposed device works as follows.

After heating of the cathodes of the thyratrons, voltage is applied to the anodic pep; In this case, the 2T thyratron burns, since a silent potential is applied to its grid when charging the 1C capacitor. After closing the switch VK. the 2T thyratron is extinguished, and the IT piratron is ignited, as a result of which a current begins to flow to the excitation winding of the OVV exciter.

As the capacitance 1C is discharged, the negative potential on the 2T thyratron mesh decreases. When the value of this potential reaches the ignition potential, the 2T thyratron is unlocked and with the help of the switching capacitance С If suppresses the IT thyratron. In this case, the current through the winding GBB begins to flow in the opposite direction.

Subsequently, after the discharge of the capacitance 2C, the IT thyratron is unlocked, and the Chiratron 2T goes out, which leads to a new change in the direction of the current in the winding of the OVV.

The duration of the cathode and anodic periods, as well as the frequency of the multivibrator, are determined by the time constants of the discharge circuits of the capacitors 1C and 2C. By changing the parameters of these circuits, it is possible to carry out independent regulation of the cathode and anode periods.

The subject is invented and

A device for periodically changing the iolarity of a dc generator feeding a galvanic bath, changing the direction of the excitation current of the generator exciter, characterized in that, in order to smoothly adjust the frequency and voltage ratio, it is made according to the scheme of an asymmetrical multivibrator containing two controlled thyratron, each of the anodal and the excitation winding of the exciter included.