SU756567A1 - Static dc converter - Google Patents

Description

Union of Soviet

Socialist).

Republics (11)

State Nomenclature of the Council of Ministers of the USSR for Inventions and Discoveries

DESCRIPTION

Inventions

TO AUTHOR'S CERTIFICATE (61) Additional to author. certificate (22) Announced 08.09.78 (21) 2666139 / 24-07 with application no. (23) Priority (43) Published! 5.08.80 Bulletin No. 30 (45) Date of publication of the description (51) M. Kl. ^{k 0211} 3/135 // И.02М 7/515 (53) UDC 621.314.57 / 088.8 / (72) Authors G. M. Burov, A. K. Mamedov, V. V. Markin, V. A. Kostryukov , A.P. Prolygin, inventions V. A. Skibinsky, V. A. Chistyakov and 10. I. Feldman (71) Applicant / 54 / STATIC DC-CONVERTER

The proposal relates to the field of electrical engineering, in particular pre-construction g-technology, and can be used as an auxiliary power supply for metro cars, trams, and trolley buses powered by a direct current contact network.

Known static converters for converting DC voltage of one level to DC voltage of another level, consisting of a primary unregulated or adjustable inverter, a controlled rectifier and a secondary inverter 1-3.

Significant disadvantages of such converters is that each of them consists of two converters - the primary one, which converts the constant voltage of the contact network into constant voltage to power the DC loads and recharges the battery and the secondary, which converts the received constant voltage into alternating voltage for supplying fluorescent lighting. In this case, the starting 'currents of liu; minescent lamps are more than 2 times higher than the nominal values, and therefore the switching elements of the secondary converter are calculated at the maximum value of the starting currents, which leads to an increase in 10 dimensions, switching losses and a decrease in the efficiency of the converter.

The purpose of this proposal is to increase the efficiency and reducing the weight and dimensions of the power supply by simultaneously converting a direct current of one voltage to direct and alternating current of another voltage, that is, combining the functions of two converters in 20 one static converter, with a non-curable inverter, connected to the secondary winding of the output transformer of which controlled rectifier, inductive-capacitance25. filter and additional output transformer, the primary winding of which is connected to the cathodes of the thyristors emogo otdeleu rectifier and on from the output filter inductance-capacitance decoupling diodes. In addition, to ensure continuous supply of AC load when there is a short-term absence of a 'voltage-on-line' circuit, the TpreduamoFren peak-inverter, the elements of which are combined with the output elements of the converter, which 'will allow; increase reliability and reduce the number of elements used.

A schematic diagram of the converter is shown in the drawing.

The converter consists of a power unregulated inverter 1. to the output of which, through the transformer 2 ', a controlled rectifier is connected, consisting of thyristors 3 and 4, to the cathodes of which the primary winding \ additional output transformer 5 is connected, to the secondary winding of which load 6 is connected. Through decoupling diodes 7 and 8 and an output filter consisting of. inductor 9 and capacitor 10 receives power from load 11 and recharges the battery; battery 12. The circuit provides additional thyristors 13 and 14 and capacitor 15, which together with elements 7 and 8, 5, 9, 10 form an additional peak inverter.

The converter operates as follows.

If there is voltage in the contact network, transformer 5 with load 6 and DC loads 11 and 12 are supplied with power from a controlled rectifier consisting of thyristors 3 and 4, with the help of which stabilization is ensured, the output voltage when the load is changed. current and input voltage. Through decoupling dybds 7 and 8 N; the output filter, consisting of a choke 9 and a capacitor 10, receive power. current 1 1 r produced g subdischarge of the battery 12.

To power the load 6 / for example, fluorescent} lamps /, ί to the cathodes | thyristors 3 and 4 ^are connected ^{- the} primary winding of the transformer 5, the middle point of which | 'is connected to the middle point of the secondary winding of the transformer 2. Thus, in each half-cycle of the operating frequency, the corresponding' ι halves of the primary winding of the transformer ~ transformer 5 'are attached, Stabilized stress In the secondary winding of the transformer 5, an alternating voltage is induced, which supplies the fluorescent) lamps.

To the thyristor 14, the control pulses are phased with the control pulses of the thyristor 3, and to the thyristor 13 are the control pulses phased with those supplied to the thyristor 4. The control pulses of the thyristors 3, 4,

13, 14 are supplied continuously regardless of the presence of voltage in the contact network. When the voltage in the contact network is present, the thyristors 13 and 14 are closed, since the reverse voltage is applied to them at the moment of supplying the control pulses, and when the voltage disappears in the contact network, the potential of the anodes of the thyristors 13 and 14 relative to the midpoint of the transformer 5 becomes positive, and the peak inverter starts to work, receiving power from the battery 12, while the thyristors 13 and 14 are power thyristors, the transformer 5 is a power transformer, the decoupling diodes 7 and 8 are reverse diodes, and the filter choke 9 is com mutating inductance, and capacitor 15 - switching capacity of the peak inverter. Thus, the peak inverter, which is a parallel inverter with reverse diodes 7 and 8, continues to power the already switched on lamps when the voltage in the contact network disappears.

The economic efficiency of this converter is mainly expressed in an increase in efficiency, reliability and a decrease in weight and dimensions, since it does not have secondary energy conversion by inversion to obtain an alternating current source, the fluorescent lamps are launched from a more powerful source power supply, and the pick-up elements are designed for short-term operation of the power supply of already switched on lamps at the time of passage of the rolling stock of neutral inserts.

Claims (2)

Claim 1. A static DC-DC converter, for example, to supply the rolling stock's own needs, containing an unregulated autonomous inverter with an output transformer, the secondary winding of which has a midpoint, and is connected at its ends to the anodes of the thyristors of the controlled rectifier, whose cathodes are through decoupling diodes and a filter connected to the DC output of the Converter, characterized in that, in order to increase the efficiency and reducing the overall dimensions during the simultaneous conversion of direct current of one voltage to direct current and alternating current of another voltage, the primary windings of an additional transformer are connected to the cathodes of the thyristors of the rectifier, the middle point of the primary winding of which is connected with the midpoint of the aforementioned first transformer. 2. The static converter according to π. 1, characterized in that, in order to ensure continuous supply of AC load, to the output terminals of the DC converter, the thyristors of the additional inverter are connected through the filter, and the switching capacitor is connected to the terminals of the primary winding of the additional output transformer.