SU964940A1 - Device for relay control of traction electric motor - Google Patents

Description

(54) DEVICE FOR RELAY CONTROL OF THE TRACTOR ELECTRIC MOTOR

The invention relates to electrical engineering, in particular to the automatic control of permanent electric drives. current to is intended to regulate the current limiting of the traction 9 elec- trodes & amps of electro-mobile installations. A relay motor regulator, containing a thyristor breaker, serially connected differentiating links and amplifiers, a frequency sensor in the motor core circuit, connected to the first input of the serially connected trigger trigger and connected to a comparator, the output of which is connected to the second input trigger, is known. and to the differentiating link in the connection circuit of the thyristor pre-switch, the inverse gate of the coincidence circuit is connected to the differentiating link in the turn-off thyristor circuit breaker device does not provide ZOdnako off key tiristrrnogo Failure signal. feedback. This leads to a sharp increase in current, a wide range of operating conditions of the power equipment and the appearance of a high level of interference in the supply network. The closest in technical terms to the invention is a device for relay current of an electric motor, containing a generator of driving pulses, connected via interlocking blocking and delayed pulses to the inputs of the crossing unit, {the fugia inputs of which are connected respectively to the outputs of the structure changing unit, unit comparison of current and predetermined values of the current of the core, electric motor, inversion unit, connected to each other and with a pulse transformer of the current of the core of the electric motor, output The switches of the switching unit are connected via a trigger to the block of structure change, inverse, the output of trigger & is connected to the amplifier of impulses from opening the thyristor key, and the other & The disadvantage of this device with the disappearance of the feedback signal or the impairment of the functional performance of the pulse current converter is the stepwise increase of the controlled current to a value flax exceeding the permissible value, as well as the level of interference in the power supply network, and as a result, the occurrence of emergency operation modes of electrically mobile installations. The purpose of the invention is to increase reliability. The goal is achieved by the fact that the device is connected in series with a rectifier and an additional comparison unit, a matching circuit, serially connected to a pulse shaper, and an amplifier, opening pulses of a thyristor switch, contain a serially connected one-oscillator, a matching circuit, a pulse amplifier, and an amplifier pulses closed - series-connected one-shot, addition circuit, pulse amplifier, moreover, pulse current transducer By connecting the input of the rectifier, and the output of which further comparator block output connected respectively to the input unit and coincidence circuit, you move pulse shaper connected to the input adder circuit, and the block SWITCH Cheney .gpodklyuchen to the input of matching circuit .On FIG. 1 shows a diagram of the device; in fig. 2 shows timing diagrams for the operation of the device when the new feedback signal has disappeared. The device contains (Fig. 1) a generator 1 of driving pulses connected via drivers 2 and 3 of blocking and delayed pulses to the inputs of switching unit 4, the other inputs of which are connected to structure measuring unit 5, comparison block 6, inversion unit 7 interconnected and with a pulsed current transformer 8 connected to the core of the electric motor 9, the outputs of block 4 are connected h & cut trigger 10 to block 5, the inverse output of trigger 10 is connected to the amplitude 11 of the opening thyristor switch 12, another trigger output Operator 04 9 is connected to the Amplifier 13 of the akryvanyi thyristor key 12, and Shaper 3 is connected to the input of the unit 5. The sender 14 and the additional comparison unit 5 are connected in series. Hema 16 coincidence is connected in series with pulse shaper 17, and amplifier 11 contains successively connected one-shot 18, hem 19 of match, pulsed amplifier & 20. Amplifier 13 contains successively connected one-shot 21, add-on circuit 22, pulsed usi the input of the rectifier 14, the output of which and the output of the additional block 15 are connected respectively to the inputs of the circuit 16 and 19, the output of the generator 17 is connected to the input of the circuit 21, and the block 4 to the input of the circuit 19. The block 6 of the comparison It comprises a series-connected generator 24, a sawtooth voltage and a comparator 25, the input driver 24 connected to the output pulse current converter 8 and the output of comparator 25 to a second input of the flip-flop 26 and the inversion unit 7 with one of the inputs of the switching unit 4. The inversion unit 7 comprises a series-connected trigger 26 and a coincidence circuit 27, the first inputs of which are connected to a pulse current converter. Switching unit 4 is implemented on a matching logic circuit and performs the function of a control Ivshyls distributor. .,. The measuring unit 5 of the structure 5 is made using integrators to determine the average relative duration of inclusion. The device works as follows. In the absence of a current l of the electric motor 9 (Fig. 2), the pulse current converter 8 generates an alternating voltage of a rectangular form with an initial frequency fo. The result of the comparison by the comparator 25 of the voltage Ug, corresponding to the value of the current setting 1 h; and the sawtooth voltage from the shaper 24, is fed to the inputs of the switching unit 4 and the trichter 26 of the inversion unit 7. The voltage pulses from the outputs of the comparator unit 6 and the pulse current converter 8 switch the trigger 24 to opposite steady-state conditions. The output voltage of the logic circuit is the same as 27 will correspond to I. Therefore, the presence of voltage impulses at the output of block 6 compare the NIN eliminates their appearance at the output of block 7 of inversion.

When the motor 9 is started from a stationary state, the voltage pulses of a constant frequency from a formative 3 delayed pulses arrive through the switching unit 4 to the first input of the 1O flip-flop, setting it in one stable state, and through a skim 19 coincidence, the pulse amplifier 20 amplifier 11 - to open thyristor 12 (pulse of sprouting O c (Fig. 2). The current core ij and the switching frequency of the pulse converter 8 increase,. When the value of T reaches 1, the comparison block b stops the formation of voltage pulses and

the output pulses of the voltage of the inversion unit 7 through the switching unit 4 are fed to the second input of the flip-flop 1O, setting it in the opposite steady state. The negative voltage front 0-j (Fig. 2) from the direct BBIXO of the flip-flop 1O triggers the one-shot 21 of the amplifier 13, and the voltage pulse goes through the addition circuit 2.2., The amplifier 23 closes the thyristor switch 12 (voltage pulse 11). The core current of the electric motor 9 and the frequency of the pulse current converter 8 are reduced. The voltage pulses of a constant frequency from the former 3 delayed pulses, arriving at the input of the trigger 10, set it to an initial steady state. By the negative voltage front Ug, the one-shot 18 of the amplifier 11 is started, and the voltage pulse Ug is fed through the coincidence logic 19, the pulse amplifier 2O to open the thyristor switch 12. Then the process is repeated.

Consequently, with the relative duration of switching-on O, 5 (the first control structure), the opening of the thyristor switch 12 is carried out by the voltage pulses of a constant frequency, and closing by the relay method (when the current reaches the value of the setting current T.).

Increasing the value of the thyristor switch 12, the block 5, the change of the structure 3 fixes the average value, 5 and after passing the pulse of a constant frequency from the formers 3 of the switch 3, it switches the logical 8L0 and 1entov of the switching unit 4. In this case, the passage of voltage pulses of the inversion unit 7 to the second input of the flip-flop 4 through the block 4 is prohibited. Trash 10 is in the same STRUCTURE state, the TT-driver key 12 is open, and the core current of the electric motor 9 is increased.

When a constant frequency arrives from the generator 3 through the switching unit 4 to the second trigger input, the steady state of the latter changes to the opposite one. The negative front voltage bjg triggers the synchronizer 21 amplifier J53, and the voltage pulse is fed through the logic circuit 22, the pulse amplifier 23 to close the thyristor switch 12.

 When the current l decreases to the magnitude of the current, the settings to the first input of the trigger 10, through the block 5, a voltage pulse is output from the output of the comparator block 6, which sets it to its original steady state. The negative voltage front U triggers the one-shot 18 of the amplifier 11, and the voltage pulse Ug comes through the matching logic 19, the pulse amplifier 20 to open the thyristor switch 12. The current increases until the voltage pulse from the constant frequency from the second input to the second input of the trigger 1O Next, the process is repeated.

Thus, at-Jf 7 0.5 (the second control structure), the opening of the ti of the radar switch 12 is carried out by the relay method (when the current decreases 51kor to the value of the current setting & ki 1), and the closing is done by pulses of constant voltage this frequency.

Consequently, the switching of the control structure of the thyristor switch under; the constant frequency of current control core i is maintained during commutation (A. The device operates when the feedback signal disappears as follows.

Claims (2)

The voltage pulses (4vg. 2) from the output of the pulse current converter 8 (fdg. 1) are fed to the rectifier 14. The voltage U from the output of the rectifier 14, corresponding to the value 1, goes to the input of the additional comparator unit 1.5. The magnitude of the voltage Ug-ii reaching the other input unit 15, in this case, the voltage across the unit, and the output voltage of the unit 15 is higher than the voltage Ui. The voltage Ud in CHI entering the inputs of the logic circuit will coincide 19 amplifier C psh will return the passage of pulses of a constant frequency from the output of block 4 from the driver 3 or pulse voltage Ug from the output of the one-shot 18 to the opening of the thyristor switch 12, Except for that, eg Uii and U are stationed; they are connected to the inputs of the additional circuit. Matching 1b. The output voltage Ts of the circuit 16, corresponding to the value of the value O, goes to the input of the imaging device 17. The voltage (J, in this case, is equal to O and allows the passage of voltage pulses from the one-cycle 21 to the closing of the thyristor switch 12. When the signal U disappears from the output Converter 8, after opening the thyristor key 12, the voltage U / j from the output of rectifier 14, corresponding to the value O, prohibits the passage of pulses Ug to open the thyristor key 12. At the same time, the voltage U equal to value I, starts the generator 17 imp through the duration of the recharge; switching capacitor of the thyristor key 12. The voltage pulses UK are fed through the coupling circuit 22, the pulse amplifier 23 to the closing of the thyristor key 12 (voltage pulses and). In addition to an open circuit signal U. and the failure of the converter 8, an abnormal mode of its operation is possible, with KOTioiioM, the pulse voltage is asymmetric both in terms of the level and duration of the different pulses. The voltage U, at STOt, corresponds to the value 1, but its value is greater than the voltage Uj /. The voltage U, corresponding to the value O, prohibits the passage of control pulses (Jg to open the thyristor key 12. A voltage U, equal to the value, triggers the driver 17 after a time equal to t. Voltage impulses 0, through the addition circuit 22, a pulse amplifier 23 arrive at the closing of the thyristor key 12 (voltage pulses U). Similarly, the passage of voltage pulses of a constant frequency from the driver 3 to the opening of the key 12 and 4 "5R is applied to the voltage pulses of the voltage received at the closing of the thyriogorny Key 12 is in the initial state of the proposed device. Thus, the prohibition of the passage of opening pulses and the formation of the closing pulses of the thyristor key is carried out in case of a break in the signal path from the pulse current converter, as well as its failure, thereby preventing the switching of the key . In this case, the reliability of the entire device and the movement of electric rolling stock is ensured. The invention is a device for relay control of a traction electric motor, comprising a generator of driving pulses, supplied through blocking and delayed pulse drivers to the inputs of the switching unit, the other inputs of which are connected respectively to the outputs of the structure changing unit, the comparison unit, the inversion unit interconnected and with a pulse current converter of the motor core, the outputs of the switching unit are connected via a trigger to the modifying unit, the inverse output is a trigger connected to the amplifier of the opening pulses of the thyristor switch, another output to the amplifier of the closing pulses, a driver of delayed pulses is connected to the input of the structure changing unit, characterized in that, in order to increase the reliability, a sequentially connected rectifier was inserted into it, and an additional comparison unit, a coincidence circuit connected in series with a pulse shaper, and a thyristor switch opening pulse amplifier contains a one-pulse connected in series, another scheme No, pulse amplifier, closing pulse amplifier - series-connected one-vibrator, addition circuit of a pulse amplifier, the pulse current converter of the electric motor being connected to the rectifier input, the output of which and the output of the additional comparator unit are connected respectively to the inputs of the first and second matching / output circuits the pulse driver is connected to the input of the addition circuit, and the switching unit is connected to the input of the second coincidence circuit. Sources of information taken into account in the examination 1. USSR author's certificate for application N9 2757637 / 24-07, cl. H 02 R. 2. USSR author's certificate number 481476, cl. H 02 P 5/16, 1976.