SU809445A1 - Power-diode reactive power compensator - Google Patents

Description

(54) VALVE COMPENSATOR RELATIVE POWER

one

The invention relates to electrical engineering and can be used in the development of static compensators with increased speed.

Known valve static compensator circuits contain a capacitor bank connected in parallel with a kodgor reactor (reactor transformer) connected in series with thyristor valves connected antiparallel and equipped with a phase control system.

The drawbacks of this circuit when it is used to increase the throughput and stability of ultrahigh voltage power transmissions are the need to increase the installed capacity of the capacitor battery to provide static transfer stability by not using the overload capacity of the capacitors and the installed power of the reactor (transformer) to compensate for the excess capacitor battery .

It is also known a device for compensation of power regs, containing a peaKTOV-1 transformer with two secondary windings, one of which has thyristor valves connected, and the other is a capacitor battery. The transformer in this circuit uses a relative capacitor bank as a voltage divider, the magnitude of which varies with the angle of regulation of the thyristor valves, which

0 allows you to smoothly adjust the power of a capacitor battery using its overload capacity to provide a margin of static transmission stability L2J.

five

The disadvantage of this circuit is the occurrence of a transient process in an oscillatory circuit L-C, formed in parallel by a capacitor battery and reactor 0 (reactor-transformer), when switching thyristor valves. The duration of the transient is determined by the quality factor of the equipment of the valve compensator.

To achieve a minimum of power and energy losses, it is necessary to ensure the highest quality factor of the compensator equipment. At the same time, to strictly maintain voltage 0 on the power line

With the help of a valve but an ID of the compensator it is necessary to have low Q-factors of the elements of its equipment.

The purpose of the invention is to increase the efficiency of the valve compensator.

The goal is achieved that in a valve compensator of active power containing an capacitor battery, a reactor (reactor transformer) connected in series with an oppositely connected thyristor is connected in parallel to the reactor, and the thyristor control system is connected to the controller output connected to the valve compensator connection point, in the oscillating circuit formed by a capacitor bank and a reactor (reactor-transformer), an active resistance, shunt, is introduced, for example, a thyristor switch, the control system of which is connected to the auxiliary output of the controller. In the proposed compensator, an additional resistance is added, a switch made, for example, on antiparallel thyristor valves, an additional control system, the resistance being connected in series with a capacitor battery or reactor (reactor-transformer) and connected with a switch, the additional control system of which connected to an additional controller output.

FIG. 1 shows a functional electrical circuit of a valve compensator with an active resistance in the circuit of a condenser battery; FIG. 2 - the same in the thyristor key; in fig. 3 - the same, with switching of the active resistance through the transformer in FIG. 4, the same, with two reactors.

The compensator contains a transformer transformer 1 primary winding of which is connected to the power line 2. One of the secondary windings of the reactor-transformer 1 is connected in series with the thyristors connected in parallel, as well as with the thyristor key 3, and the other secondary winding - with a capacitor battery 4, the control of the thyristor key 3 is performed by the controller 5 through the control system b, the control driver pulses). In series with the capacitor battery 4 (FIG. 1), active resistance 7 is switched on, which is shunted by a thyristor switch 8, which can be constructed with built-in resistance, i.e. Both elements can be made in one block. A thyristor switch control system 9 is also connected to the output of the controller 5, the input of which is connected to the point of connection of the valve compensator.

Active resistance 7 and the thyristor switch 8 (FIG. 2) are connected in series with the thyristor key 3. With this switch on, the thyristor switch. The switch can be replaced by any other high-speed switch, for example, a vacuum one.

The capacitor battery 4 and the active resistance 7 (Fig. 3) are at the potential, and the active resistance 7 is bridged by the thyristor switch 8 by means of an intermediate transformer 10.

A conventional transformer 11 is connected to power line 2 (FIG. 4), to the secondary winding of which two reactors are connected in series

0 12 and 13. A capacitor bank 4 is connected to the common point of reactors 12 and 13.

The device works as follows.

5 The appearance in the L-C oscillatory circuit of a valve compensator of a noticeable transient process, which could lead to fluctuations and voltage distortions at the point of connection of the compensator, is due to

a significant change in the turn-on angle of the thyristor key 3. The latter is a consequence of the sudden change in voltage on the electric power supply line 2, to which the regulator 5 reacts, as a derivative voltage. Normally, the thyristor switch 8 is on and shunts the active resistance 7, while the losses in the thyristor switch 8 are negligible

versus losses in thyristor

key 3. When a derivative of a certain voltage appears, the controller sends pulses to the control system 9, which block

supplying the trigger pulses to the thyristor switch 8. Thus, active resistance 7 is introduced into the oscillating circuit L-C leading to a rapid decay of the transient process. When the normal voltage mode is restored on the power line 2, the regulator 5 releases the lock from the control system 9, which again turns on the thyristor switch 8, shunt

active resistance 7.

The main goal of the proposed technical solution is to ensure the rigidity of maintaining the voltage at the point where the valve compensator is connected with large recoveries in the power system. In addition, the rapid decay of the transient in the L-C circuit improves the reliability of the system 6 control thyristor key ;. i,

in which at this time (nlchiilyut

additional follow-up pulses are produced, and their limited number is allowed. Finally, the introduction of active resistance into the power transmission circuit improves its dynamic stability.

The effect of the proposed device is determined by the possibility of reducing the power transmission stability reserves due to more stringent maintenance of urobular voltage at intermediate power transmission points, as well as improving the reliability of the valve compensator.

Claims (2)

1.ReichertK. and others. Controllable Reactor Compensator for Extensive Utilization of High .Voltage Transmission Systems, CIGRE, 0 Paper 31/04, 197. 2. USSR author's certificate No. 558350, cl. H 02 4 3/18, 1975. / Yy -I -Ich M4-) m f well UIH b