SU72378A1 - Transformer substation - Google Patents

Description

Trackless transport with contactless power supply to crews with high frequency current can be applied to roads for several tens or even hundreds of kilometers. In this case, there may be cases when the sources of primary energy (thermal or hydroCEC) are located only in one or two points of the high-frequency highway route and there are no transmission lines passing close to this highway.

An example is the Georgian Military Road, which can be energized only from its two ends - from the cities of Tbilisi and Ordzhonikidze.

It is possible to install powerful high-frequency substations at both ends of such a road and run along the road a high-frequency, high-frequency current transmission line. However, it is known that the higher the frequency of the current (within certain limits), the more expensive the transmission line is.

Applying high-voltage direct current to a single-wire or two-wire transmission line could significantly reduce the cost of powering high-frequency transport roads. In this case, along the road, at a distance of 10–20 kilometers one from the other, substations are located that convert the direct current of high voltage to high frequency current, which already enters the traction networks located under or above the roadway.

The problem of powering substations is complicated by the fact that the converters have a number of auxiliary circuits (heat circuit, control circuit) that require high frequency current or low voltage direct current. Having local sources of energy at high-frequency substations (internal combustion engines or bulky batteries) is not always desirable.

This task can be solved by applying such a power supply method in which all types of electrical energy necessary for the operation of high-frequency converter stations are transmitted via one or two wires from the central station.

Ns 72378

The subject matter of this invention is a converter nodal station, powered by a variable flux current, filtered from the fixed component and used for auxiliary purposes. According to the invention, the variable component feeds the glow and control circuits of the ionic direct current inverters into the high frequency alternating current supplying the traction line, and the constant component provides the anodic values of these inverters.

Such a power feed is applicable to all types of converter devices, for example, with conventional electronic generator lamps. However, the simplest, most concise and economical design of this principle is obtained in the case of the use of magnetrons, converted by the cathode field, for the conversion.

The foregoing summary is explained in the accompanying drawing, which shows a diagram of a central substation and one of the track converting substations.

Here / is the primary winding of the power transformer, 2 and 3 are the secondary windings supplying the gas turbines 4-15. Through the inductors 16 and 17 of the circuit breaker 18, the direct current is supplied to the two-wire line 30. Both wires are under the same voltage with respect to ground, since the middle point of the rectifier installation is grounded

This same two-wire line 30 supplies a high frequency voltage. Using a coupling capacitor 19 and 20, a high-frequency transformer 21 is connected to the line. The capacitor 22 compensates for the scattering inductance of the transformer 21.

A separating capacitor 23 receives high-frequency pulses from the magnetron 24 to the transformer 21. The cathode of this magnetron is heated from the transformer 25, which receives power from the master oscillator 26. The choke with a ferromagnetic core is designated 28. The anodic voltage is applied to the terminals 29; 27 - stop choke.

At each track high-frequency substation, separation of direct and high-frequency currents takes place: high-frequency current, right, is fed to the heat circuit, direct current is directed to the anode circuit.

Numbers 31-32 indicate separation capacitors at a high-frequency substation. 55 - a high-frequency auxiliary transformer. From it, through the rectifier 34 and the choke 35, the battery 36 is charged, from which the auxiliary mechanisms of the substations are actuated, such as: pumps for circulating water, cooling the magnetrons, lighting, relay service, etc.

37-transformer of the first magnetron; 38, 39, 40-capacitance and inductance, shifting the phase of the voltage on the second transformer 41 by 45 ° relative to the transformer 37.

42 and 43-secondary (filament) windings of high-frequency transformers, 44 and 45-ferromagnetic chokes. 46 and 47 magnetrons, 48 and 49 high-frequency chokes through which voltage is applied to the anodes of the magnetrons, 50 and 51-split capacitors, 52 and 53-capacitors of the anode oscillating circuits of the magnetrons, 54 and 55 high-frequency transformers, feeding feeder compensated lines 56-59. To prevent the formation of standing current waves and voltages in these lines, capacitors 60 are connected in series and parallel between inductors 61 in them. Automatic devices 62-65 turn on and off portions of the traction network, depending on the appearance of the load in them. The drawing shows a four-wire network, each section of which consists of two loops

66, 67.68, 59, etc. The number 78 denotes the crew of high-frequency transport.

Traction network sites, for example, 66 and 67, are made in the order of several hundred meters each. Capacitors 70-77 are included in the network. The shorter each section of the traction network, the less time these capacitors are loaded, the less the total nominal kilovoltampers can be. However, with the shortening of the plot, the number of automatic switching on and off switches increases (62, 63, 64 ...). The economic optimum of the length of the section depends on the density of the movement and on the price ratio of contactors and capacitors.

The proposed power supply system for high-frequency roads provides simple control of all converter stations from one central point.

To start up the entire system, the high frequency of the converter 24 is switched on first in line 30, and the cathodes of all the magnetrons of the converter track substations are heated. At the same time, recharging of batteries at substations begins (if necessary), then a high-voltage direct current is turned on at the central station, the magnetrons receive anode power and begin to generate a high-frequency current.

The drawing does not show the system of blocking prices for cooling and magnetron heating pumps.

The power consumed in the circuits of the cathodes of the magnetrons (they are at the same time the control circuits) does not exceed 2-3% of the converted power transmitted by direct current. Therefore, the voltage of the high-frequency current and its strength are several times smaller compared to the direct current, and therefore the presence of a variable high-frequency component has little effect on the calculation of the power transmission line from the central station to the converter track substations.

The characteristic impedance of a two-wire overhead line is about 600 2. There will be no high-frequency current waves and high-frequency voltage in the line if the resistance of the load connected to the line at all its points also has this value. The loads (converter stations) are scattered along the entire line, but during operation the magnitude of the high-frequency power consumed by them does not change. Therefore, a transition transformer can be installed at each substation, which would lead to the resistance of the load to the characteristic impedance of the transmission line. With such a system, when a load is transferred from one portion of the transmission line to another, both the current and its voltage change simultaneously, and the resistance Z of the load remains unchanged.

Due to the fact that the transmitted AC power is small, there is no need to accurately coordinate the resistance of the transmission line and the resistance of the load. The presence of a certain number of standing waves of a current and a high frequency voltage in a line will not noticeably affect its efficiency.

Subject invention

A converting substation powered by a direct current with a variable component, filtered from the constant component and used for auxiliary purposes, characterized in that the variable component feeds the current and control circuits of the ion converters of direct current to high frequency alternating current. the power supply line, and the constant component - the anode circuit of these converters.

- 3 - № 72378