SU58153A1 - Device for limiting the current of a synchronous compensator during automatic voltage regulation - Google Patents

Description

In the process of automatic adjustment of the voltage of the synchronous compensator, such an overload of the adjustable machine may occur, which in some cases may lead to the switching off of Mamniibi with maximum protection to even damaged; 1e of the machine.

At the same time, in order to preserve the stability of parallel operation, the facilities: you need in emergency cases to briefly give the maximum excitement to the machine, and to slosh and overload it. .

The subject of this copyright certificate. is a device for limiting the current of the synchronous compensator (in short, the limiter), rzb.) as follows. As soon as the regulator current: the machine G1 starts r (it changes the nominal (ilk-lba, other long-term allowable setpoint 31, 1), so MhoiseHKo turns off) the speed of the accelerator of the regulator in the direction of the voltage increase; B1: L: The permanent part of the regulator remains at the same time on; if the load to the specified value occurred in the normal mode npsr hole (the voltage was set to the voltage, then the speed; the regulator's other contactors did not work, and even turned on; if it didn’t go off or after the switch off): , for example, a short circuit, then the open speed of the fast controller contactor is triggered, the iiaKopoTKO closure is all adjustable corspor; -: in the excitation circuit of the exciter; after some exposure. due to the requirements of sustainability of parallel operation, and also Bci3Mo; -KHOCTH ui regulating controller; 1 machine; the speed contactor is turned off (but only if there is a problem; overload the machine); where there is a maxim,. h.support-time1 and oipanichig-L | I agree with B; de; Zhkai. from the top of the line. Maximally sewn CHHxpoiUi-.jro kumpe; {sator.

At a time when sapr. T. vleng-e B tse;: ;; excitement excite::, closes on the corpus aly. Normally pj3o i: - i: yТ1.; M by the STROD STVu10Sh.IM KOHTCKTOp-jM

Serzomotor starts to traverse

rheostat (if there is an overload of the machine to the stop limiter) in the direction of increasing the sop::) tBlei before the momeite off is very expensive without a contactor. Therefore, after the contactor is turned off, the current in individual cases may be more than that before the contactor is triggered. This is necessary, in particular, to return the relay. Maximum protection. The circuit can be returned to the initial position either by hand or by u.it automatically after reducing the current to the value corresponding to the return current of the limiter overcurrent relay.

Both at the first and at the second stage of operation of the limiter, a signal can be set, after which the duty officer can interfere with the operation of the regulator; for example, after switching off the motor part, it is possible to change the adjustment of the regulator by means of the installation resistors and re-enable the motor part when the voltage is changed, etc.

Essence; 3) arbiennes; on a single use of the max maxi; al; relays for controlling the regulator in the described manner in a simpler manner, as shown in the drawing, in FIG. I and 2 of which depict the electrical diagrams of two BapsiaHTOB proposed devices, and in FIG. 3 - diagram; 1 replaced; adjustable voltage 3 azero and post-accident period, due to the removal of the device in operation.

The reacting part of the limiter consists of two overcurrent relays, on 1 jen: {s; x corresponding to two phases adjustable machine; 1 l (Fig. 1). setting the relay overload / closing its contacts and switching on from the intermediate relay 2. which opens the contactor of the contactor, turning on the servo motor of the voltage regulator in the direction of voltage over voltage. Thereby increasing the load. In addition, relay 1 at its actuation.and: a) connect a regulator contact, including a normally open short-time quick disconnect controller, with relay time 3 and 3 via normal. IBHo closed contact of the intermediate relay - /, and b) applies voltage ( p.ios) to normally open

relay contact 4, which allows the latter to self-block when cpciOuTbisafrriri.

If the voltage jolt is so great that the contact of the regulator closes, Blykoyayunin normally opens the 1-speed high-speed contactor, then simultaneously with the latter, time relay 3 and intermediate relay 5 are turned on.

Time relay 3 has two contacts: one acting instantaneously for self-blocking and the second with a time delay for switching on intermediate relay 4.

Intermediate relay 5 provides a voltage to the contactor that turns on the servo motor in the direction of increasing resistance in the excitation circuit of the driver.

When an intermediate relay is triggered ;; t the following: a) the winding circuit of the normally open high-speed contactor opens; b) the 4th self-blocking role 4 through the relay 2, c) the time relay 3 and the intermediate relay 5 open.

If the time delay of relay 3 is high for the operation of relay 5 (i.e. ec: i; t, relay 5 reduces the stator current so much that it returns to its initial position the relay contacts /, the controller automatically switches on again when the voltage is very low.) to overload the stator, the limiting pitch is working again, etc.), then you need to use a three-contact time relay with independent time delays to close two contacts with a slip contact to switch on relay 5, with self-locking of the latter and disconnecting its normal. 1 short-circuit : m contact relay 4 (Fig. 2). In this case, the irreducibility of the relay 5 should be chosen from such a calculation that when restoring the pre-voltage value of the voltage, the limiter comes to (th position and vice versa, if the controller remains lowered after the accident, the regulator remains off.

The author indicates that the latter scheme was tested in the laboratory. To increase the reliability of the limiter was necessary

re-configure one group of contacts of a relaying relay 4 in such a way that the opening of a normally closed relay contact, through which .b: i time relay 3 is turned off (and intermediate relay 5) occurs no earlier than the closing moment of the normal U contact opening, through which the -f relay is self blocking.

Consider the features of emergency and post-accident mode at an electrical substation and the operation of the controller and limiter during this period.

At the moment of short-circuiting near substation-1k, there is a sharp decrease in voltage on the substation buses; after that, the damaged area and the cap are disconnected: e also rises sharply. Since, with a sharp decrease in voltage, many motors turn off at consumers, then s is the first time after from .-: switch ;; the damaged area, the voltage iw, the tires of the substation, rises to the extent exceeding the emergency condition; after that, the consumer motors are gradually switched on and the voltage on the substation tires decreases (Fig. 3).

Under these conditions, the operation of a voltage regulator is extremely important in order to increase the stability of the parallel operation of the system — dynamic Koff during a short-circuit and static during an impedance condition; Yn low HIH tension. Under these conditions, the current limiter should not prevent the operation of the controller. And dejstz:; tel: o, the proposed limit.: At the moment of short circuit, 1in disables only the servomotor of the regulator in the direction of increasing voltage (the servomotor operation due to the slowness of the action does not give anything for dynamic stability), leaving 3 quickly works2: o ts1 (to increase dnnamicheskoy stability. After the expiration of the BjWMeHir.

By considerations of safety of the machine, the speed of the machine is shut off. LY KOFiTaKTOp. short-circuited all adjustable resistance in the excitation circuit of the exciter. Only a part of the regulator remains on, working in the direction of decreasing voltage. This part naturally comes into effect when the pressure is higher than the voltage and is loaded by the compensator; at the same time, the limiter comes to its initial position and turns on the regulator upward. At the same time, a reactive power reserve is formed at the synchronous compensator. When a post-accident reduction occurs, the regulator maintains voltage due to the resulting reserve of power and thereby increases the static stability of the system.

The subject matter of the invention.

Instrument for limiting the current synchronous compensated; And with automatic voltage regulation with the help of a fast-acting rheostat type regulator operating according to the combined smooth and impact change of the first one, characterized in that, in order to increase the dynamic stability during short circuits and current limiting during overloads, two maximum current relays are applied /, /. designed through an intermediate relay to open the servo contactor circuit; parts of the regulator in the direction of increasing the voltage and turn on the high-speed part of the regulator for some short time through the relay with an exposure of time so that during the post-fault voltage increase only the part of the regulator working on the side of the voltage reduction remains.

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