SU1065960A1 - Starting device for automatic putting backup user supply into operation - Google Patents

Abstract

1. STARTING DEVICE FOR AUTOMATIC RESERVE INPUT. . CONSUMER POWER SUPPLY, containing the comparison circuit of the voltage phases of the main and backup sources and end circuits AND, the outputs of which are connected to the executive bodies of switching off the breakers of the operating inputs and turning on the section switch, characterized in that, in order to improve the speed and reliability of operation, it has been entered a current blocking body consisting of two current pulse formers and one AND logic, a summation block containing two AND – NOT schemes and one AND circuit, the control block; valid phase shift, an over-phase shift block containing seven AND-NOT logic circuits and two flip-flops, an output pulse shaping unit consisting of the AND-NOT logic circuit, a load element per pulse, an element with a given output pulse duration, an output inverter pulse, and the current formers of the current blocking current inputs are connected to current transformers in each of the monitored sections, and the outputs are connected to the input of the current block I.organi, the output of which is connected to one of the inputs : the first AND-NOT scheme and the second AND-NOT scheme of the summation unit, the outputs of which are connected via the ANDA circuitry circuit to the input of the permissible phase shift adjustment unit, the output of which is connected to the inputs of the first and second AND-NOT circuit of the overshoot unit two second inputs connected to the outputs of pulse shapers of monitored voltages, and outputs to the inputs of the third and fourth AND-NOT circuits, as well as to one of the inputs of the fifth and sixth circuits of the AND-NOT unit for the phase shift exceeding, the outputs of the third and fourth AND circuits -NOT § block pr Phase shift elevations are connected to the second inputs of the fifth and sixth AND-NI circuits, as well as to the inputs of the seventh AND-NI circuit of this unit, the output of the fifth NI-NI circuit is connected to the forward input of the first trigger and to the reverse input of the second flip-flop: phase shift, the output of the sixth circuit IS-NOT is connected to the reverse input of the first trigger and the CD input of the second trigger of the block after phase shift, the outputs of the first trigger of the phase shift offset switch are connected to one of the inputs Ot) of the final AND circuits, and the output of the second trigger of this block oedinen to one input of AND-NOT output pulse generating unit. the second input of which is connected to the output of the summation unit, and the output through a switch is connected to the input of a delay element by one pulse connected by an output through a switch to the input of an element with a given output pulse duration, the output of which is connected to one of the inputs of the final circuits AND, as well as an inverter with the third inputs of the first and second circuits of the IS-NOT block for the phase shift exceeding.

Description

2. The device according to claim 1, 1 and 2, in that the pulse shapers with a duration up to half-period are used as pulse shapers, and the triacs are used as the executive bodies for switching off input switches.

The invention relates to power supply schemes of industrial enterprises and can be used as a high-speed start-up organ for automatic switching on the reserve (ATS) of various consumers who do not suffer from interruptions in power supply. Breaks in electrical supply violate the stability of some loaded engines. Violation of the dynamic stability of synchronous motors, for example, type STD, STM, using-. as drives for copressors at chemical plants, oil refineries and other industries, leads to disruption of technological processes. To ensure the sustainability of consumers, it is necessary to shorten the interruption of power supply in case of various power failures.

A device is known for automatically switching on a backup power supply containing synchronous motors by determining the direction of the active power of the main power source, as well as the angle between the voltage vectors of the main and backup sources. ,

The device consists of a first phase-sensitive unit connected to the voltage of the main and backup power sources via voltage transformers, a second phase-sensitive unit reacted to the direction of the active power of the main source and connected to the voltage transformer and the current transformer of the main power source, the comparison unit the outputs of which are connected to the outputs of two phase-sensitive units, an automatic switch-on unit, connected to the output of the comparison unit 1.

The disadvantage of this device is that when the main source is disconnected, in a number of cases the direction of active power is maintained due to its flow when running from electric motors with large inertia constants to α-motors with lower inertia constants, this leads to a delay

automatic activation of backup power supplies.

The closest technical. The essence of the invention is a trigger device for automatic input of a backup power supply to consumers, consisting of two frequency comparison units and an executive unit connected to the outputs of frequency comparison units, one input of which is intended to be connected to the main power source and the other to the backup power source nutrition These frequency comparison units with the second outputs are connected respectively to the backup and main power sources, each of them contains a phase-shifting element, a driver for controlling pulses, a thyristor, and a reacting organ. The executive unit consists of a thyristor and a relay t 2.

The known device is characterized by the insufficient speed required to reduce the switching current of the sectional switch due to the presence of a phase-shifting device and a relay. The presence of a relay reduces the reliability of the device. In addition, in case of any short circuit on the section, synchronous motors will run out, as a result, the AVR device will operate and give a signal to turn on the section switch, which will create a short circuit on a healthy tire system. The device has insufficient noise immunity to strong external electromagnetic pulses,

The purpose of the invention is to increase the speed to reliability of the device.

The goal is achieved by the fact that the starting device for automatic input of backup power supply of consumers, containing a scheme for comparing the phases of voltages of the main and backup sources and final circuits AND, the outputs of which cce are connected to the executive bodies of disconnecting switches of operating inputs and switching on the sectional switch on / off blocking current, consisting of two current pulse drivers and one logic circuit AND, a summation block, two I-NOT schemes and one circuit containing an adjustment circuit is permissible Phase shift, phase overshoot block, containing seven logic circuits, NAND and two flip-flops, output pulse shaping unit, consisting of NAND logic, one delay element, pulse, element with a given output pulse duration output pulse inverter, the current forcing blockers of the current blocking device by the inputs are connected to the current transformer in each of the monitored sections, and the outputs to the input of the circuit AND the blocking device for current whose output is connected to one of the inputs of the first AND – NOT circuit and wto a swarm of the AND block of the summation, the outputs of which are connected through the circuit AND of the summation block to the input of the control unit of the permissible phase shift, the output to which is connected to the first inputs of the first and second schemes of the AND-NOT block of the phase shift control, two second inputs connected to the outputs of the forms of the monitored voltage pulses and the outputs to the inputs of the third and fourth NAND circuits, as well as to one of the inputs of the fifth and sixth circuits of the AND-NOT block for the phase shift exceeding, the outputs of the third and fourth circuits of the IS-NOT extension unit shear phase ha is connected to the second inputs of the fifth and sixth AND-NOT circuits, as well as with the inputs of the seventh AND-NOT circuit of this unit, the output of the fifth AND-NOT circuit is connected to the forward input of the first trigger and to the reverse input of the Second trigger of the phase shift exceeding unit, the output of the sixth AND-NOT circuit is connected to the reverse input of the first trigger and the reverse input of the second trigger of the phase shift exceeding unit, the outputs of the first trigger of the phase shift exceeding unit are connected to one of the inputs of the final AND circuits, and the output of the second trigger of this block is connected to one of the inputs NAND block schemes the output pulse, the second input of which is connected to the output of the summation unit, and the output through the switch is connected to the input of a delay element by one pulse connected by the output through the switch to the input of the element with a given output pulse duration, the output of which is connected to one of the inputs of the final circuits And, as well as through the inverter with the third inputs of the first and second circuits of the IS-NOT of the Phase shift excess unit. In addition, pulse shapers with a duration up to half a period were used as pulse shapers, and triacs were used as switching actuators for switching off introductory devices: silencers. Ma FIG. 1 depot structural diagram of the proposed device; in fig. 2 is a device wiring diagram; source; 1cam. The device contains 1 n 2 pulse shapers with a duration of up to half a cycle, the inputs of which are connected via transformers 3 and 4 voltages to the line voltage of the input of the main and backup power, and the outputs to the inputs of the circuit 5 comparing the phases of the voltage of the backup and redundant sources. One of the inputs of the phase comparison circuit 5 are the inputs of the summing block b, which contains the logical AND-HE 7 and 3 and AND 9. The current blocking body 10 includes two current pulse formers 11 and 12, which are threshold the device, the circuit AND 13, the output of which is connected to the inputs of the circuits AND-NOT 7 and 8. The inputs of the drivers 11 and 12 current pulses are connected to the current transformers 14 and 15 of the respective inputs. The output of the circuit And 9 is connected to the input of the block 16 of the adjustment of the allowable phase shift and to one of the inputs of the block 17 is formed. no output pulse. The output of the permissible phase shift adjustment unit 16 is connected to the inputs of the circuit 18 of the phase-shift exceeding unit 18, which contains the AND-NE logic circuits 19-25 and the flip-flops 26 and 27. The flip-flop 26 is connected to the output circuits 28 and 29 by its outputs, and the flip-flop 27 with one of the inputs of the output pulse shaping unit 17, which includes the AND-NOT 30 logic circuit, the output of which is connected via a switch in 31 to the delay unit 32 for one pulse, connected to. output via switch S 33 to the input of element 34 with a given output pulse duration, the output of which is connected to end circuits 28 and 29, as well as through inverter 35 to AND-NE circuits 19 and 20. Switches s 31 and S 3,3 serve to turn off the element delays by one pulse. The outputs of the final circuits AND 2B and 29 are connected to the executive bodies of opening the switches of the corresponding input 36, 37 and turning on the sectional switch 38. The device operates as follows. In the normal mode of operation, the consumer busbar section, which has synchronous motors, is connected by input switches 39 and 40 to the power sources and is operated separately, sectional switch 38 is disconnected. Voltages and and and equal or close

out of phase, but the phase difference does not exceed the allowable value, the difference is due to load fluctuations due to changing process conditions. The current flowing in the sections does not exceed the trigger threshold of the formers 11 and 12 current pulses connected to the current transformers 14 and 15. respectively, and on them (during the course there is a signal from the level of the logical unit. At the output of circuit 13 there is also a signal from the level of the logical unit, respectively, of the IS 7 and 8 circuits, which play the role of valves, permits the passage of pulses from the forger 1 and 2 pulses connected to the voltage transformers 3 and 4. Signals passing through the I-: NOT 7 and 8 are inverted. Heads 9 are pulses, the leading edge of which corresponds to the leading edge of the leading pulse, and the falling edge is the leading edge of the lagging. These pulses come to the input of the permissible phase shift adjustment block 16, which is a multivibrator operating in the standby mode. using, it is possible to set the permissible phase shift between section voltages based on the motor load mode). At the output of block 16, pulses are generated corresponding to the permissible phase shift. The AND-HE circuits 19 and 20 form pulses, which the passage of the AND-HE circuit 21 and 22 g are inverted, at the output of the AND-NE circuit 23 pulses are formed with intervals equal to the phase shift of the voltages U ,, and the AND-24 circuit - a signal with the level of the logical unit, the output of the circuit IS-NOT 25 - pulses with intervals equal to the difference between the permissible phase shift and present on the working inputs. The trigger 26 determines which of the sections a phase change occurs (in this case, the voltage Uj lags a little behind the voltage 0 in phase) and sends a signal with a level. Logic unit is constant for one of the final circuits And 28 or 29, and circuit AND 29. Trigger 27 determines the presence of a phase shift more than acceptable. In this case, it produces pulses equal to the phase shift of the voltages Uv, II, and II. The circuit 30 performs a logical AND operation with the pulse. themselves from the trigger 27 and the circuit AND 9, and at its output a signal is formed with a level of a constant logical unit. As a result, the element 32 delays by one pulse and the element 34 with the specified output pulse duration do not work, since they are:

transition of a signal from the level of a logical unit to the level of logical zero, i.e. from impulses. At the output of element 34, there is a signal with a constant logic level of zero, which prohibits the passage of a signal to the circuit 29, the output of which is a signal with a logic level, and the execution authorities 36 and 37 do not operate. 35 to the elements AND-NOT 19 and 20 receives a signal with a level of logical units, allowing the passage of pulses.

In the event of damage, the engines of this section run out, and immediately the phase difference between and occurs. | and EMF 2 d valid value. There are pulses at the output of the NAND 23 circuit, and at the output of the NAND 24 circuit there is a signal with a level of logical one. The flip-flop 26 switches or remains in its previous position based on the previous mode and sends a logical one signal to the final AND 28 circuit or a logical zero signal. At the output of the NAND circuit 25, a logical unit signal is generated. The trigger 27 switches to the steady state, and a logic unit signal appears at the output, which enters the AND-H.E.S circuit, permits the passage of pulses from the AND 9 circuit, and the pulses are inverted. Element 32 is triggered by one pulse, then the second. Pulse triggers element 34 with a given duration of the output signal, which produces a pulse of 0.50, 6 s, which is enough to turn off the input switch and. switch on sectioning switch. This impulse arrives at the final circuits AND 28 and 29, which forms the output of the circuit of AND 29 and a pulse of the same duration, which is fed to the executive bodies 37 and 38. An inverted impulse of the same duration arrives at the inverter 35 for the IC 19 and 20 and prohibits the passage of pulses, i.e. blocking occurs from the operation of switching off the intact input when the angle between the EMF and and vectors increases, is greater than 90 °. When switching the switches S 31 and S 33, a single-pulse delay element .32 is turned off, and the pulses from the output of the NANDI circuit 30 are fed directly to the input of the element 34 with a given output pulse duration, which is triggered by the first pulse, which reduces the noise immunity of the device but speed increases.

When a short circuit on the section, 5 for example at the point K-1, the current sharply

increases to a value much greater than the magnitude of the maximum current to short circuit, i.e. there will be more rfopora triggered shapers of 11 and 12 current pulses. Shaper 12 current pulses imposes a signal with a logic level of zero. At the output of the AND 13 circuit, a signal appears at a logic zero level, which gives the cipher for the passage of pulses through the IS – NE 7 and 8 circuits, thereby blocking the entire device from tripping. The section switch remains off. The device returns to its original state after the restoration of the normal power supply to the section and the end of the output pulse. In the absence of both voltages, the starting device does not work. The device does not respond to system-wide frequency reduction.

The invention makes it possible to increase the speed and reliability of automatic input of a reserve of consumers containing synchronous motors. The response time of a device with a delayed pulse of one pulse per unit pulse is 0.001 s and is determined by the duration of a single voltage pulse. When a delay unit was introduced for one pulse, the response time increased accordingly for one period and would be equal to 0.021 s. Improving the reliability of the device is due to the fact that it does not work when there is a short circuit on one of the sections, and when the shift of the monitored voltage fa is less than acceptable. In addition, the device when put into operation the delay unit per pulse has a high noise immunity to the effects of strong electromagnetic pulses. The device is made on logic chips, has small dimensions.

Claims (2)

1. START-UP DEVICE FOR AUTOMATIC BACKUP INPUT. CONSUMERS'S FOOD, containing a circuit for comparing the phases of the voltage of the main and backup sources and final circuits AND, the outputs of which are connected to the executive bodies. turning off the switches of the working inputs and turning on the sectional switch, characterized in that, in order to increase the speed and reliability of operation, a current blocking element is introduced into it, consisting of two current pulse shapers and one logical circuit And, a summing unit containing two circuits And NOT and one AND circuit, an allowable phase shift adjustment block, an excess phase shift block containing seven AND-NOT logic circuits and two triggers, an output pulse generating unit consisting of an AND-NOT logic circuit, a delay element per pulse, of an element with a given duration of the output pulse, the inverter of the output pulse, and the current pulse shapers of the current blocking device with inputs connected to the current transformers in each of the controlled sections, and the outputs to the input of the circuit block And the current blocking device, the output of which connected to one of the inputs; of the first AND-NOT circuit and the second AND-NOT circuit of the summing unit, the outputs of which are connected to through the AND circuit of the summing unit! the input of the unit for adjusting the permissible phase shift, the output of which is connected to the inputs of the first and second circuits of the AND block of the excess. phase shift, two second inputs connected to the outputs of the pulse shapers of controlled voltages, and outputs to the inputs of the third and fourth AND-NOT circuits, as well as to one of the inputs of the fifth and sixth circuits AND-NOT of the phase exceeding block, the outputs of the third and fourth I-NOT circuits of the phase-exceeding tree are connected to the second inputs of the fifth and sixth AND-NOT circuits, as well as to the inputs of the seventh AND-NOT circuit of this unit, the output of the fifth AND-NOT circuit is connected to the direct input of the first trigger and to the reverse input of the second trigger phase shift excess block One of the sixth AND-NOT circuit is connected to the reverse input of the first trigger and the reverse input of the second trigger of the phase exceeding block, the outputs of the first trigger of the phase exceeding block are connected to one of the inputs of the final AND circuits, and the output of the second trigger of this block is connected to one of the inputs of the circuit AND-NOT the output pulse generating unit, the second input of which is connected to the output of the summing unit, and the output through the switch is connected to the input of the delay element for one pulse connected by the output through the switch to the input element and with a given duration of the output pulse, the output of which is connected to one of the inputs of the final And circuits, as well as through an inverter with the third inputs of the first and second circuits of the AND-NOT block of excess phase shift. SU ,, „1065960 2. The device according to π. 1, the result of which is that, as pulse shapers pulse shapers lasting up to half a period are used, and as executive bodies, they are used to turn off the input switches. And turn on the section switch, triacs are used.