SU39257A1 - Device for automatic regulation of alternator voltage - Google Patents

Description

It is widely known in devices for automatically regulating the voltage of an alternator to use cathode lamps (rectifiers) connected to the generator excitation winding circuit in order to automatically vary the excitation of the latter when the voltage on its terminals is changed and to maintain the voltage constant.

In the proposed device, thyratrons are used as such rectifiers, and according to the invention, a potentiometer is used to create a potential difference between the grid and the anode of each of the thyratrons, the working part of which is included in the grid circuit and which is fed through an intermediate transformer with a load current of an auxiliary synchronous motor, connected in parallel with an adjustable generator, with the intention that the changes in the motor current phase occurring when the generator voltage fluctuates The flax generator voltage caused a change in the moment of ignition of the thyratron and, thus, the duration of the rectified current flow during the working half-wave of the current.

The proposed device is shown in the drawing, where FIG. 1 shows a circuit diagram of a device; FIG. 2 - theoretical oscillogram of operation of one phase of the device in the normal mode; FIG. 3, 4 is the same, with increasing load of the generator and 5, 6, too, with decreasing load.

The excitation circuit of the regulated oscillator / is fed from the generator bus J via transformer 2 and thyratrons 3. Thus, transformer 2 feeds the anode circuits of the thyratrons. The effect of voltage variations on the generator busbars / on the excitation current of the generator is measured through a small (on the order of hundreds of watts) auxiliary synchronous motor 4, the excitation of which is taken from an independent DC source. Engine 4 is loaded with a damper disk 5, such as brake discs, widely used in engineering (in meters, relays, etc.).

In the auxiliary motor circuit 4 there are intermediate current transformers 6, supplying and ohmic resistances connected in a star. Each of the resistances 7 is connected according to the potentiometer circuit to the grid circuit of one of the thyratrons. The circuit of the nets of thyratrons 3, in series with the working part of potentiometers 7u, includes the working part of potentiometer 8, the resistance of which is connected in parallel with the excitation winding of the generator /. The chains of individual thyratrons are connected in series with the working parts of the potentiometers 7 and the working parts of the compensating potentiometers 9 fed by the load current of the generator 7. In parallel with the excitation winding, the resistance JO is included. Operation of the device is easily discerned from consideration of FIG. 2 - 4. The following is indicated on them: // - generator voltage curve, 72 Ignition voltage of the thyratron, 75 - line voltage drop on the working part of potentiometer 8, 74 - voltage drop curve on the working part of potentiometer 7, oriented relative to lines 75; Thus, potentiometer 8 serves to create a constant voltage component in the grid circuit, in order to lift the curve M above the abscissa axis (time line or center line of the curve 77); if potentiometer 8 was not, then curve 74 would have an average line common to curve 77. Curve 74 in the normal mode is shifted relative to curve 77 by 120 °; To do this, the grid of each of the thyratrons 5 is connected to one of the potentiometers 7, so that the voltage on the grid is shifted by 120 in the direction of lag relative to the anode voltage. At the point 75 of the suppression of curves 72 and 74, the thyratron is ignited, after which it works until the curve 77 passes through zero; this produces a rectified current curve 76, shown in FIG. 2 - 4 bold lines. In normal operation, the motor current 4 is in phase with the voltage. The voltage drop in the resistance 7 after the action of the voltage compensator 9, taking into account the influence of the power factor, acts on the thyratron networks; at the same time, to achieve static control, as already mentioned, a voltage drop in resistance 8 is applied to the voltage drop in the ohmic resistance 7, proportional to the generator excitation current 7. When the generator load increases and the bus voltage decreases, the auxiliary engine 4 will be overexcited with respect to the network; therefore, its current will be lagging behind, as a result of which the ignition of thyratrons will be earlier (Figures 3 - 4). This causes an increase in excitation current and voltage leveling. After the transitional regime (Fig. 3), when the regulator (auxiliary engine) will be inactive, the increased excitation current will be supported by an increased voltage drop in the resistance 8, i.e. the raising of the ignition phase (see Fig. 4 for steady state). mode with increased load). Exactly in the same order, the adjustment will be carried out with decreasing load and increasing voltage on the tires; but now the ignition phase will shift in the direction of lag, i.e. the thyratrons will be ignited later (Fig. 5). This will reduce the excitation current, which at steady state (Fig. 6) is represented by a line having a smaller ordinate than during a transition mode (Fig. 5). In the proposed device, the voltage of the generator 7 all the time takes the value corresponding to the electromotive force of the auxiliary engine 4; thus, in order to change the magnitude of the voltage setting, it is necessary to act on the regulator 77. According to the author, the speed of voltage rise in the proposed control system can be very large (on the order of several thousand hours per second); it is due solely to the time constant of the transformer's dissipation field. The subject matter of the invention. 1. An apparatus for automatically controlling the voltage of an alternator using lamp rectifiers connected to the field of an excitation winding of a generator and provided with grids whose potential depends on the mode of operation of the generator, characterized in that to create a potential difference between the grid and anode of each of the thyratrons 5, applied as rectifiers, a potentiometer 7 is applied, the working part of which is connected to the grid circuit and which is fed through the intermediate transformer with current of heating narrow auxiliary synchronous motor

4, connected in parallel with an adjustable oscillator, with the intention that the fluctuations of the current phase of the engine 4 relative to the generator voltage caused by the oscillator voltage to cause the trigger moment of the thyratron and, therefore, the duration of the rectified current to flow during the operating half-wave current.

2. The form of the device according to claim 1, characterized in that, in series with the working part of the potentiometer 7, the working circuit of the grid includes the working part of the potentiometer 5 connected in parallel with the excitation winding of the generator.

3. The form of the device according to paragraphs. 1 and 2, characterized in that the working circuit of the potentiometer 9 supplied by the generator current is included in the grid circuit.

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