SU1628132A2 - Device for automatic synchronization with constant angle of lead - Google Patents

Abstract

The invention relates to electrical engineering and can be used to synchronize synchronous generators, such as ship, using the method of precise synchronization. The aim of the invention is to increase the reliability of B sets with asymmetric load, and by introducing shaper 33, 34 difference modulus, relay elements 35 and 36, and OR-HE element 37, it allows control of voltage moduli W ex. Switching on the generator for parallel operation occurs when it is permissible modulo the values of the voltage difference of all phases of the network and generator. 7 il. A t: i (L O) No. 00 00 to 14)

Description

The invention relates to electrical engineering and can be used when synchronizing synchronous generators, for example, shipboard methods of accurate synchronization.

The purpose of the invention is to increase work in networks with asymmetrical loads.

FIG. a block diagram of the device for automatic synchronization with a constant angle of advance is presented; Fig. 2 is a schematic diagram of a three-cycle standby multivibrator; fig.Z - schematic diagram of the time relay; 4 is a schematic diagram of a one-shot; FIG. 3 is a block diagram of the protection of the synchronizer against unacceptable module deviations in phases b and from the renerrator and the station, as well as the vector and time diagrams of its operation; Fig. 1 shows the vector and time diagrams of the operation of the synchronizer protection against unacceptable phase shifts in phases B and from the generator and the station; figure 7 - timing diagrams of the synchronizer during the adjustment of the frequency in phase a of the station and the generator.

The device (Fig. 1) contains signal conditioners 1, 2, 3, 4, 5, 6, the inputs of which are connected to the same phases a, b, respectively, from the station and generator 7 connected to the station buses with load 8 via a locking linear contactor 9. The output of the signal conditioner 1 is connected to the input of the three-cycle standby multivibrator 10, the first output of which is connected to the second input of the first element 11, the second output to the second input of the second element 12, and the third output to the first input of the third element i 13. The output of the signal conditioner 2 is connected to the first inputs of the elements 11 and 12 and through the inverter 14 with the second input of the element i 13. The outputs of the elements 11 and 12 are connected respectively to the S inputs of the flip-flops 15 and lh, and the output of the element i 13 to the R-inputs of the flip-flops 15, 16, 17. The second inputs of the And 18, 19, 20 elements are connected to the forward output of the trigger 15, and the first inputs of the And 21, 22 elements are connected to the inverter. The forward output of the trigger 16 is connected to the third inputs of the elements

Q 5

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Commodity And 19, 20, 22 and the second input element And 21, and inverse - with the first input element And 18. The outputs of elements And 21 and 18 are connected respectively to the R- and S-inputs of the trigger 23, the direct output of which is connected to the first input of the element And 20, and the inverse output with the first input element And 19 and the second input element And 22, the output of which through time relay 24 is connected to the S-input of the trigger 17. The inverse output of the trigger 17 is connected to the fourth input of the element 14, Outputs of the signal conditioners 3 and 4, 5 and 6, respectively, are connected to the inputs of the EXCLUSIVE circuit OR 25 and 26. Outputs circuits 25 and 26, respectively, are connected to the inputs of one-vibrator-switches 27 and 28. The outputs of the EXCLUSIVE OR circuits 25 and 26 are connected via inverters 29 and 30 to the synchronous inputs C of the flip-flops 31 and 32.

The device also contains drivers of modules of difference 33, 34, the inputs of which are connected to the voltages of the phases b and c, respectively, the station and the generator, and the outputs are connected respectively via relay elements 35, 36 to the inputs of the OR-NOT element 37. Direct outputs D- Triggers 31 and 32, the output of the element OR-HE 37, and also the direct output of trigger 17 are connected to the inputs of the AND 38 element. The outputs of the AND elements 38, 20, 19 are the first, second, and third outputs of the device, respectively.

A three-stroke standby multivibrator (FIG. 2) consists of three series-connected pulse amplifiers and contains resistors 39-44, electrolytic capacitors 45-47, and transection pores 48-50. The duration of the output pulses of the multivibrator 10 is determined by the capacitance value of the electrolytic capacitors 45-47.

The time relay (Lig.Z) consists of resistors 51, 52, electrolytic capacitor 53 and inverter 54. When melting at the time relay input 24 logic units (+5 V), a capacitor is charged through the circuit + TJ | ,, resistor 51 , capacitor 53, After a time equal to ST, where T is a time constant, the inverter 54 is triggered. With a logic zero, the input of time relay 24 does not charge the capacitor 53.

516

As a trigger 15, 16, 17, 23, a trigger with separate RCSs was adopted.

One-shot 27 and 28 are made. According to the unified scheme shown in FIG. 4, which includes a single-channel waiting multivibrator 55, a capacitor 56 and a variable resistor 57.

A single vibrator is triggered by input pulses and generates calibrated pulses of the estimated duration. The shaper of the module voltage difference 33 (FIG. 3a) contains a transformer 58 with primary windings 59 and 60 oppositely connected to a voltage 4C3 b, respectively, of the station and generator 7. The secondary winding of the transformer 58 is connected to the input of the Grantz circuit of the rectifier 61. The output of the rectifier is connected to the input of the filter G-scheme 62.

The relay element 35 (Fig. 5a) implements a relay characteristic with an adjustable deadband and can be performed, for example, on operational amplifiers with nonlinear feedback.

The device works as follows.

The outputs of the signal conditioners 1, 2 are followed by rectangular pulses with a duration equal to half the period of the voltages of the phase a of the station and the generator (Fig. 7). When rectangular pulses come in from the output of the signal conditioner 1 to the input of the three-stroke standby multivibrator 10, pulses are generated at its outputs: first on the first, then on the second, and on the third. The pulse duration at the first output of the multivibrator sets the advance angle. The pulse duration at the second output of the multivibrator 10 and the time delay of the relay 24 determine the permissible switching frequency difference. The adjustment of the device frequency begins when the frequency difference (5 ± 1) Hz between the station and the connected generator 7 is allowed. Let the frequency of the generator be less than the frequency of the station's network (FIG. 6). At the time of formation of the signal at the third output of the multivibrator 10 and the absence of a pulse from the driver 2 using elements 14 and 13, a signal is set that triggers 16, 17 to the zero state (,)

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There comes a moment when the pulse at the output of the imaging unit 2 appears simultaneously with the pulse at the first output of the multivibrator 10. At the same time, from element I sets the trigger 15 to the one state (,), and the trigger 16 remains in the zero state for the time being. The signals from the direct output of the trigger 15 and from the inverse output of the trigger 16 form a signal in the input element of the element 18, which sets the trigger 23 in one. the state before that he could be in any state). There comes a moment when the pulses at the output of the imaging device 2 appear simultaneously with their output on the second output of the multivibrator 10, and an signal is generated at E gcood of the element 0 AND 1 2 setting f f from the vHHn state.

Thus (.:, The stack moment triggers 15, IS, 23 C are charged in one state –1, z trigger 17 is in the zero state, and a signal (ARR 2) is generated at the output of the AND element 20 for the effect of the subdivider - gslsratora in the direction of increasing CRGT-P :,

Frequency generator frequency set station. It will intimidate the moment when the scarecrow at the exit of the shaper 2 is emissing simultaneously with the momentum is. multivibrator 10 second. Vrv chiHciri r output element And 12 gstg J-r r. c is the trigger 16 in the circuit, and the trigger 15 of the bale ostke1c is in the nilgrome state. The link 1 from the direct switch trigger J6 and the inverse code of the trigger 15 are forged at the output of the g21 signal, which sets the gritsr 23 to the zero state. There comes a moment when the impulse at the output of the Former 2 appears ol-impulsively with a pulse at the first output of the multivibrator 10. Then, on the state of the K 1 1 element, a signal is generated that sets the trigger-5 to one state. B -, v npi; between the setup of flip-flops and the single state of the output of element I22, whose inputs are connected to the direct output of flip-flop 16 and inverse outputs of flip-flops 15 and 23, a signal is generated, triggered, time relay 24. If the frequency difference between the synchronization and the station

0

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0

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exceeds the permissible value for switching on, then the trigger 15 is set to one state before the time relay 24 is triggered. In this case, the signal at the output of the element 22 is removed, the time relay 24 stops and the trigger 17 does not have time to switch. At the output of the element 19 and 19 (output 3), the inputs of which are connected to the direct outputs of the flip-flops 15 and 16 and the inverse outputs of the flip-flops 17 and 23, a signal is generated to affect the servo motor of the speed governor of the drive motor of the generator 7 in the direction of decreasing frequency. If the difference between the frequencies of the generator 7 and the network of the station is less than the permissible difference of the switching frequency, then the relay at the D-flip-flop 32 is logical zero (fig. Bb), which prohibits the operation of the line contactor 9.

Let at the moment of time t-, before directly passing the command to operate the linear contactor 9, the state of the phase voltage stars of the generator and the station is determined by the vector diagram (Fig. 5b). Since the phase shifts in phases b and from the station and the generator are zero, a logical unit is generated at the output of the D-flip-flops 31 and 32, which is not

5 prohibits the passage of a command from the output of the trigger 17.

However, the differences in magnitudes of the voltages in phases b and c above the permissible limits (Fig. 5b), which cause

Meni 24 is triggered earlier than the appearance at output OR-NOT 37

thirty

35

Ger 15 is set to one state, and sets trigger 17 to one state, the inverse output of which blocks AND 19. From the forward output of trigger 17, it supplies 25 seconds to one of the inputs of AND 38, the other two to logical one from the outputs of D-flip-flops 31 and 32, if the asymmetry in phases b and from the station is within acceptable limits. In this case, at the output of the element 38 (output I), a logical unit is formed, which gives the command to turn on the line contactor 9 of the generator 7 and connect it to the station.

Let at the moment of time t, before the command to actuate the linear contactor 9 is directly transmitted, the state of the phase voltage generator and station stars is determined by the vector diagram (Fig. B). The signal conditioners of 3, 4, 5, 6 form rectangular pulses equal to half the period of phase stresses Ggr, Urc, l ce,, Ucc (Fig. 66). At the outputs of the EXCLUSIVE OR circuits 25 and 26, rectangular pulses are formed, the duration fuwn., Which is compared with the allowable t additional; on D-flip-pax t

respectively 31 and 32. If t.rtr ,; then the output imp. idop In the first P-chrigger, a logical unit is formed and, conversely, if tyiMii is AOP ,; This forms a logical., cue zero. At time t, for the case corresponding to the vector diagram at the output of D-flip-flop 31, a unit is formed, and for an arbitrary zero that prohibits the triggering of the linear contactor 9. Thus, the proposed protection of the synchronizer’s sync (with prediction) of emergency situations associated with the distortion of the system of linear and phase voltages on the station tires due to asymmetry and non-sinusoidal behavior on the load side, makes it possible to exclude erroneous inclusions of the generator to the tires and protect the station from additional current shocks that would be possible without this protection.

Taking into account the asymmetry in phases b and from the station by the synchronizer when determining the time of connecting the synchronized generator to the station will allow more reliably controlling the process of generating electric energy by the station and contributes to its survivability.

Claims (1)

Invention Formula Device for automatic synchronization with a constant angle of desc. No. 1527687, characterized in that, in order to increase the reliability of operation with asymmetrical loads, two formers of a module of a phase voltage difference module, two relay elements, a two-input element OR NONE, and the inputs of the first and second modulators of the difference module are connected respectively to the terminals for connection to logical zero, prohibiting the operation of the linear contactor 9. Thus, the proposed protection of the synchronizer, endowed, unlike other protection, the properties of the assessment (prediction) of emergency situations. associated with the distortion of the system of linear and phase voltages on the station buses due to asymmetry and non-sinusoidality on the load side, eliminates erroneous switching on of the generator to the station buses and protect the station from additional current jolts that would be possible without this protection. Taking into account the asymmetry in phases b and from the station by the synchronizer when determining the moment of connecting the synchronized generator to the station will allow to more reliably control the process of generating electric energy by the station and contributes to increasing its survivability. Invention Formula A device for automatic synchronization with a constant angle of advance on the auth.St. No. 1527687, characterized in that, in order to increase the reliability of operation in networks with unbalanced load, two formers of a module of a difference of phase voltages, two relay elements, a two-input element OR NOT, and the inputs of the first and second formers of a module are introduced into it. the differences are connected respectively to the terminals for connection to the voltages of the other two phases of the hetero- nial elements to the inputs of the OR-NOT element, the generator, the outputs of the formers, the output of the OR-KE element are connected to the difference modules and connected via the first and second relays of the device. P-CD- 154} 0 output   5J bv-d -; FIG. 2 -0 EXIT with l i U-5G.-.- JTV -0 p  ffJO) p GG 1C TO but chs g 00 + : C18291 ") P V- f- : j t7 29 31 0 five eight : 6 ; b 3 (1 "I Js G f Ctu ( Urc U cc U t ЈL. n (n t Jxo Aon HI Jiu Jd t eleven B: i ion HZ  five 3) Fig 7