SU1418677A1 - Protected power supply system - Google Patents

Abstract

The invention relates to electrical engineering and is intended for powering electronic equipment. The purpose of the invention is to increase reliability by extending the functionality of the protection. Current sensor 4, phase control sensor 5, driver 6, voltage sensor 7 with driver

Description

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Pulses, block 8 comparison of the time of the voltage deviation from the set limits, block 9 of the setting of the time of switching-off when overcurrent, the counter of 10 operations, the driver

11 output levels, key

12 control of the power relay, node 13 lock the key, driver U of the general signal Failure, source 15 of the reference voltage, relay 16 li of the output for connecting the auxiliary

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 . The invention relates to electrical engineering and is intended to be used in: - electrical powering of electronic equipment.

The purpose of the invention is to increase reliability by expanding the functionality of the search (increasing the sensitivity of the sensor, simplifying and providing four types of information on failure).

FIG. 1 shows a block diagram of the device; in fig. 2 - current sensor; in fig. 3 - shaper output levels.

The power supply system with protection contains a power transformer. 1, a protection unit 2 and an indicator unit 3, the protection unit 2 comprising current sensors 4, phase control sensors 5, a driver 6, a voltage sensor 7 with a pulse driver, a unit

8 Comparison of time of voltage deviation from the specified limits, block

9Tasks overload current overload, counter 10 operations, driver 11 levels of output signals, relay control key 12, key lock node 13, common failure signal generator 14, reference voltage source 15, relay 16 and terminals for connecting an auxiliary source The relay 16 is connected by its contacts between the terminals for connecting the three-phase input voltage and the primary windings of the power transformer 1, the other terminals of which are connected through the sensor 4 currents and connected to the sensor input ka 5 phase control output

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source. If the fault disappears within a specified time, the protection unit 2 automatically restores the operating mode. It is not possible to connect the power without switching on the protection unit 2. The latter generates signals from disconnecting the output voltage from the specified limits, about the absence of one of the phases of the supply voltage, about current overload, 2 hp f-lg, 3 ill.

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which is connected to the input of the imaging unit 6 and the input of the imaging unit 14 of the common failure signal, the output of the imaging unit 6 is connected to the first input of the imaging unit 11 of the output signals, the output of the current sensor 4 is connected to the first input of the overload trip unit 9, the first and second outputs of which are connected respectively To the input of the counter 10 operations and the first input of the node of locking the key 13, the first output of the counter 10 operations is connected to the second input of the Former-1 level 11 levels of output signals, and the second input of the node is locked the key 13 is connected to the second input of the failure signal generator 14, the output windings of the power transformer 1 are connected to the output terminals and the first input of the voltage sensor 7 with the pulse driver, the output of which is connected to the first input of the block 8 comparing the voltage deviation from the set limits, the first output of which is connected to the corresponding input of the generator 11 of the output signals, and the other to the corresponding inputs of the node lock key 13 and the generator 14 of the common failure signal, the output of the latter is connected to tvetstvuyuschim input of the 11 levels of the output signals, the output key locking unit 13 is connected to the control input of the relay switch 12, the output of which through the relay coil 16 is connected to vodom for connecting the plus water vg- auxiliary power supply, which is also connected to the input

the source 15 of the reference voltage, the outputs of which are connected to the corresponding inputs of the current sensor 4, the sensor

7, voltage with a pulse shaper on the load has deviated from the bolt, a deviation time comparison unit 8, a voltage from a predetermined level, a trip time setting unit 9 for overcurrent and formed limits for a time exceeding the specified one. When the power supply system is disconnected due to the load voltage output from the specified protection limits of 11 output signal levels, the KPO-JQ unit 2 receives a common signal to this, the current sensor 4 contains a current transformer 17, the primary windings of which are connected to the input 4 of the sensor and output - with the input of the rectifier 18, the output of which (5 times higher than the set value, Protect- is connected to the first voltage separator 19, the output of which is connected to the non-inverting input of the comparator 20, in parallel with which is a shortcut and a signal that disable si The power system occurs due to the voltage on the load deviating from the preset limits. During the –warmer -2 block also monitors the current of the primary windings of the power transformer 1, disconnecting the supply voltage from the power supply system.

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The sensor 21, the inverting input of the com- puter, is a predetermined time if the current of the parator 20 is connected to the output of the voltage divider 22, the input of which is connected to the corresponding input of the current sensor 4 connected to the output of the voltage source, and the first resistor 23 is connected to the output of a comparator, which is connected through a series-connected diode 24 and the second resistor 25 is connected to a non-inverter input of the comparator 20, in addition, the driver 11 levels of output signals is made on four transistors 26-29 and four limiters Yelnia resistors 30-33, wherein the bases and collectors of transistors connected to respective inputs and output of the output levels, and limiting resistors connected to the terminal for connecting a reference source direction and the collector of the corresponding transistor.

The device works as follows.

The system is turned on when an auxiliary source is connected. At the same time, the relay control key 12 supplies power to the relay 26, which connects with its contacts a three-phase voltage to the primary windings of transformer 1, which are connected to the star via current transformer 17 of current sensor 4. In normal operation, the protection unit 2 and the relay 16 do not affect the operation of the system.

The protection unit 2 provides control of the voltage on the load with the output signal of the declination of the voltage of the primary windings of the power transformer 1 exceeds the set value, the automatic test switch-on after the set time of the supply voltage after it is turned off, caused by an excess current of the primary windings of the transformer of the set value, test power supply voltage after overcurrent, complete disconnection of the power supply from the power system after a specified number of test power-ups and in Failure schachu common signal, and that signal that the power system shutdown occurred due to an overcurrent primary obmo-. transformer current 1,

In addition, unit 2 monitors the presence of the voltage of all dd of the three phases of the supply voltage, the total signal of the Failure and the signal that one of the phases of the supply voltage is absent when the voltage drops in any phase.

The voltage from the load arrives. a voltage sensor 7 with a pulse former. In this unit, the load voltage is compared with the voltage of the source 15 of the reference voltage. In the event of a voltage deviation at a load from the given limits, a signal is generated, which arrives at block 8, which compares the time of voltage deviation from the specified limits. If the duration of the deviation of the voltage on the load from the preset Limits exceeds the predetermined duration of the reference impulse of the block 8, from its output the signal through the key lock node 13 will

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setting the load within the specified limits; disconnecting the supply voltage from the power supply system in the event that the data of these limits is exceeded by a specified time. When the power supply system is disconnected due to the output voltage on the load from the preset protection limits exceeding the preset

kaz and a signal that the power supply system is disconnected due to the deviation of the voltage on the load from the preset limits for a period of time exceeding the preset

unit -2 also monitors the current of the primary windings of the power transformer 1, disconnecting the supply voltage from the power supply system

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0 set time in case the current is about

the primary windings of the power transformer 1 exceeds the set value, automatic test switching on after a given time of the supply voltage after turning it off, caused by an increase in current, the primary windings of the transformer of the set value, counting the test switching on of the supply voltage after current overloads, complete switching off of the supply voltage power supply system after a specified number of test inclusions and the overall signal failure, as well as the signal that the power system was disconnected due to e overcurrent primary obmo-. transformer current 1,

In addition, unit 2 monitors the presence of voltage of all g of the three phases of the supply voltage, the total signal of the Failure and the signal that one of the phases of the supply voltage is absent when the voltage drops in any phase.

The voltage from the load arrives. a voltage sensor 7 with a pulse former. In this unit, the load voltage is compared with the voltage of the source 15 of the reference voltage. In the event of a voltage deviation at a load from the given limits, a signal is generated, which arrives at block 8, which compares the time of voltage deviation from the specified limits. If the duration of the deviation of the voltage on the load from the preset Limits exceeds the predetermined duration of the reference impulse of the block 8, from its output the signal through the key lock node 13 will

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steps onto the control key of the power relay 12, the key 13 is closed, and the relay 16 disconnects the supply voltage from the power system. If the duration of the voltage deviation at the load from the specified limits is less than the duration of the reference impulse of the block 8, a signal does not appear at its output and the system does not turn off. The output signal of the block 8 is fed to the former 11 levels of output signals directly and through the driver 14 of the common failure signal.

The current of the primary windings of the power transformer 1 in the current sensor 4 is compared with the reference value, and if it is exceeded at the current output 4, a signal is generated that arrives at the shutdown time setting unit 9 during a current overload, in which a reference pulse of a given duration is generated.

The trigger signal of unit 9 goes to counter 10 and triggers to the key lock node 13, thereby locking the control key of power relay 12, and relay 16 turns off the power supply systems for a time equal to the duration of the fixed block pulse 9. At the end of this pulse, an automatic switching on the power supply system, since the control key of power relay 12 is opened and the contacts of relay 16 are closed, turning on the power supply system. If a current overload occurs again in the turn-on field, the system shuts down by a time equal to the duration of the reference pulse of block 9, and the next test switch-on, etc. After a predetermined number of test switches, equal to the capacity of the counter 10, the power supply system is completely turned off by the output signal of the counter 10 trigger unit. From the output of the latter through the key lock unit 13 and the relay 12, a signal arrives to turn off the relay 16, and the system turns off. In this case, the signal from the output of the counter 10 is fed to the common failure signal generator 14 and to the driver 11 output signal levels, the output of which generates a common signal Failure and a signal that the power supply was disconnected due to the current overload of the primary windings of the transformer 1.

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The sensor 5 K01GTROL phase input is connected to the point of connection of the primary windings of the current transformer 17, i.e.

g to the point where, in the presence of three phases of the supply voltage and the absence of asymmetry of the load on the phases of transformer 1, there is practically no alternating voltage. In case of loss of any

About three phases of the supply voltage at the input of the sensor 5, a signal appears that through the formula 6 and the driver 14 of the common failure signal enters the generator 11 levels of the output signal, the output of which generates the Failure signal and the signal about the loss of one of the phases supply voltage. Turn on the power system after turning it on

0 5l.okom 2 can only by turning off and

reconnecting the auxiliary voltage of the protective unit Z.

The sensor works as follows. The primary windings of the power transformer 1 flow through the primary windings of the transformer 17 of the current. The voltage of the secondary windings of the current transformer 17 is proportional to the current flowing through the primary windings,

0 is fed to the rectifier 18, to the output of which a divider 19 is connected. The comparator 20 compares the voltage de: voltage 19 to the voltage of the divider 22 which is the reference.

35 If the primary windings exceed a given value, the voltage of the divider 19 is higher than the voltage of the divider 22; a high voltage level appears at the output of the comparator. Resistor 25 and diode 24 are designed to create a hysteresis in the characteristic of the comparator, which is necessary for accurate operation of devices connected to the output of the remote control of the comparator 20. Condenser 21 is designed to eliminate false positives of current sensor 4 when the power supply is turned on and to protect from impulse noise.

0 Shaper 11 levels of output signals as follows. In the case of normal operation of the power supply system, all four transistors 26-29 are open and a health signal in the form of a logic voltage is generated at the output terminals for55. In the case of the operation of the protective unit 2 for any reason, the corresponding transistor of the output level generator

the signals are closed, which ensures the formation of a signal. Voltage failure. Log.1. The signals of the protection unit are fed to the output level generator, so that when any of the transistors 27-29 is locked, the transistor 26 is locked. Thus, the integrated signal Failure and the Tolerance, Phase, Overload signals are generated. Such a construction of the protection unit 2 of the output signal level generator allows to increase the reliability of the control of the power supply system and makes it possible to determine if there is a break in the connecting line for transmitting the output signals of the output level signal generator to the recording device, which also increases the operational reliability of the object in which the system is used power supply with protection.

The positive e) effect consists in expanding the functional capabilities of protection, namely in providing protection against overcurrent or short latching, from loss

three-phase supply voltage phases, 30 at overload, the first and second output voltage deviations above the specified limits. In this case, the device makes a predetermined number of such inclusions, before turning off the power source, and turns off the power only after a predetermined time. If the malfunction disappears within a specified time, the protection system automatically restores the operating mode. The positive effect is also the inability to turn on the power supply system without turning on the protection unit. The signals generated by the protective unit about the deviation of the output voltage from the set limits, the absence of one of the three phases-supply voltage, and overcurrent significantly increase the operational reliability of the power supply system.

Claims (3)

1. The power supply system with protection, containing a power transformer, a protective unit and an indicator unit, is so that, in order to increase reliability by expanding the functionality of, five boards, a current sensor, a phase control sensor, a driver, a voltage sensor with a pulse driver, a unit for comparison of the time of voltage deviation from the specified limits, a block for overcurrent shutdown time, a trip meter, an output level driver signals, a power relay control key, a key lock unit, a common failure signal generator, a reference voltage source, a relay and outputs for connecting an auxiliary source, the relay including its contacts between water for connecting three-phase voltage and the conclusions of the primary windings of the power transformer, other outputs of which are connected through the current sensor and connected to the input of the phase control sensor, the output of which is connected to the input of the former and the first input of the common failure signal, is connected to the first input of the former. output levels, the current sensor output is connected to the first input of the trip time setting unit from 0 five 0 five the moves of which are connected respectively to the first input of the key lock node and the response counter, the first output of which is connected to the second input of the output signal level generator, and the second input to the second input of the key lock node and the second input of the common failure signal generator, the output windings of the power transformer are connected with the output terminals and the first input of the voltage sensor with the pulse shaper, the output of which is connected to the first input of the unit comparing the time of the voltage deviation from the specified limits The first output of which is connected to the third input of the output level generator, and the second output to the third input of the key lock node and the common failure signal generator, the output of which is connected to the fourth input of the output signal level generator, the output of the key lock node is connected to the control key input the relay, the output of which through the relay coil is connected to the positive output; w the connection of the auxiliary source and the power input of the voltage source, the first output of which is connected to Current input of the current sensor, second input of the voltage sensor 1C pulse generator, block Comparison of the time of voltage deviation from the specified limits and the block of the trip time overload current, the second output of the iOnopHoro voltage source is connected to the fifth input of the level driver output - | signals. i 2. The system according to claim 1, distinguishes between the fact that, in order to increase sensitivity, the current sensor of the primary winding of the transformer is high on the current transformer, the world is two, two dividers connection, a pair of two resistor: x, a condenser | a diode, and the primary winding-20 shaper of output current transformer sig1KI levels are connected to the primary windings of the power transformer and the other to the inputs sensor control There are four transistors and four limiting resistors, with the bases of the transistors connected to the corresponding inputs of the | phases, the secondary winding of the transformer-25 world level of output signals, | az, the current is connected to the input of the terminal, the output of which is connected to the first voltage divider, the output of which is jporo connected to the non-inverting input of the comparator and through a capacitor 30 The emitters are connected to the common power output, and the collectors are connected to the power supply and to the corresponding outputs of the driver through appropriate limiting resistors. with a common power supply terminal, the inverter input of the comparator is connected to the output of a second divider connected to the terminals for connecting a reference voltage source, the output of the comparator is connected via a first resistor to the input of a second voltage divider and a serially connected second resistor and a noninverting diode. 3. The system according to claim 1, characterized in that, in order to simplify and provide four types of information in the form of a predetermined level of output signals about the failure, the tolerance of the parameters, the presence of the phases of the supply voltage and the overload current There are four transistors and four limiting resistors, with the bases of the transistors connected to the corresponding inputs of the The emitters are connected to the common power output, and the collectors are connected to the power supply and to the corresponding outputs of the driver through appropriate limiting resistors. f f QmKQ.3 -O Tolerance -ABOUT Phase H) Overload. Fi.Z