SU705903A1 - Power-level emergency protection arrangement of nuclear reactor - Google Patents

Abstract

ALARM DEVICE FOR PROTECTION OF NUCLEAR REACTOR power level comprising electrometric amplifier unit with negative feedback at the input and komparato-'rom emergency protection at the output za- mopschosti level sensor coupled to the second input of the comparator aaschity emergency, emergency trigger za- 'panels connected to the contractor, and the indicator of measurement limits, characterized in that, in order to increase the reliability of the emergency protection and simplify maintenance, it is equipped with upper and lower level comparators, inputs to the outputs are connected to the output of the electrometric amplifier, and the outputs to the control unit, the output of which is connected to a switching unit consisting of a series-connected reversing shift register, a measuring limit encoder and an actuating relay unit, as well as a protective signal forming unit consisting of a waiting multivibrator, the input of which is connected to the output of the upper level comparator, the logic circuit I, the first input of which is connected to the output of the emergency protection comparator, the second input - with the output of the waiting multivi Rathore, and a third input through a logical OR gate connected to bl01 & lt outputs; and logical c ^ whom And, each first input of the logical AND circuits connected to the corresponding contact switch tsrede- 'la settings, and each second input - to the output of the encoder measurement limits. ''. (L • ^ o elso ooo

Description

The invention relates to a nuclear device and can be used in a control and protection system of nuclear missile power control and emergency protection according to the power level,

| :. , - -. A device is known for emergency protection of a nuclear reactor consisting of an electrometric amplifier. the negative feedback unit at the output and the threshold device at the step, the setpoint adjuster connected to the second input of the threshold device of the emergency protection trigger AND connected to the executive relay of the emergency protection and the indicator.

The current from the ionization chamber is transformed in the electrometric force-1 body into voltage cables, which are compared in the threshold device with the level of the reference voltage at which the threshold device should operate. When the threshold device is triggered, the safety trigger triggers causing the safety relay to trip.

However, since this device is single-limiting, it cannot be used to measure an input field when measuring it within seven to eight decades,. The closest to the invention according to T | echnical essence is the nuclear emergency protection device. peaiKTopa by power level, containing an electrometric amplifier with a negative feedback unit at the input and an emergency protection comparator at the output, a power level specifier connected to the second INPUT of the emergency protection companion, an emergency protection trigger connected to the executive relay, and a measurement limit indicator.

The output voltage of the electrometric amplifier at each measurement limit varies from zero to a constant value, so it is possible that the alarm trigger comparator will trigger at each measurement limit, provided that the output voltage of the electrometric amplifier raises the set value of the setting,

However, when entering the reactor to a predetermined power level, it is necessary to manually switch the measurement limits and, at the same time, the operator must continuously monitor the input signal and have time to switch the measurement limit before the input signal approaches the loosened value of the setpoint;

if it does not correspond to the actual value of the emergency protection power,.

The aim of the invention is to improve the reliability of emergency protection and

simplified maintenance of the device.

I,

This is achieved by the fact that the device is equipped with a comparator of the upper and the lower level, the inputs of which are under-

connected to the output of an electrometric amplifier, and outputs to a control unit whose output is connected to a switching unit consisting of a series-connected reversing shift register, a measuring limit encoder and an executive relay unit, and an emergency protection signal generating unit, consisting of standby multivibrator, input

which is connected to the output of the upper level comparator, logic AND, the first output of which is connected to the output of the emergency protection comparator, the second input - to the output of the waiting

multivibrator, and the third input through the logic circuit OR is connected to the outputs of the logic block AND, each first input of the logic circuit AND connected to the corresponding contact of the limit switch settings, and every second input to the output of the encoder of the measurement limits. The drawing shows the block diagram of the device ,

The device contains an electrometric amplifier J, the comparators of the upper 2 and lower 3 levels, the inputs of which are connected to the output of the amplifier, the control unit 4, the implementation

logical connection between the comparators and the switching unit 5, consisting of the series-connected reverse shift register -6, the encoder: 7 measurement limits, and the IC7 block 8

additional relays, which serve to connect the necessary 1x resistors, in block 9 of negative feedback in accordance with the selected measurement limit, block 10 for shaping cnPa a: in ariic protection, which consists of standby multivibrator 11, the output of which is connected to the upper comparator bypass The level, the limit switch of the settings 12, the logic 3770 of the circuit of circuit 13 and 13, one input of which is connected to the output of the emergency protection comparator 14 connected to the output of the usnpitel, the second input to the output of the waiting multivibrator, and the third input through the logic circuit OR 15 is connected to the outputs of the logic block AND 16, each first input of the logic circuits AND is connected to the corresponding contact of the limit switch of the settings, and each second input to the output of the encoder of the measurement limits, the power level generator 17 connected to the second alarm comparator input protection, emergency trigger 18, connected between the executive relay of emergency protection 19 and logic AND, as well as the indicator 20 of the measurement limits, connected to the output of the encoder. The device works as follows. From the ionization chamber placed in the nuclear reactor (not shown in the drawing), the current is applied to the input of the electric. A power amplifier 1, where it is converted into voltage signals. The current may vary by p then DKb from IU A to. The measurement limit in the device corresponds to one order of current measurement at the input of amplifier 1 (ni, 2, ... 8). The signal from the output of the electrometric amplifier I is fed to the input of the comparators of the upper and lower levels. The signal from the comparator 2 of the upper level, or the signal from the comparator 3 of the lower level, the control unit 4 generates a signal to ifep the switching of the reversing register, KOttiy through the encoder 7 and the unit 8, the executive relays make the switch. we select the measurement limit in block 9 of the negative feedback. Information on the selected measurement limit from the chipframer 7 is fed to the indicator 20 of the measurement limits. The signal from the top level comparator 2 on the need to switch to a more coarse measurement limit triggers the multivibrator, the output pulses of which close one g of the inputs of the logic circuit 13 and the time required for the duration of the liep process of the electrometric amplifier 1.. .: This ensures that false alarms are not allowed during transients occurring in the device when measuring the input signal and thus are prevented (emergency protection is triggered. The output voltage from the electrometric amplifier 1 is also fed to the Comparator of the emergency protection, the trigger level is set by the power level adjuster. When the output voltage exceeds the set value, the logic signal 1 is sent to the inputs of the AND 13 logic circuit. The limit switch setpoint sets the limit on which the safety protection comparator should operate.Let the setpoint be set by the setpoint limit switch at the n-limit of measurement, then the input of one logic circuit AND logic block will receive a logical signal 1. As the input signal rises from O to the value corresponding to the level at which the alarm safety comparator should operate, the input signal is continuously monitored until a predetermined value is reached, i.e. automatic selection of the measurement limit, and when the input current reaches the measurement n-limit, at which it is set. the setpoint is sent to the second input of the logic circuit AND a signal of logic 1 is received from the output of the encoder, and through the logic circuit OR it passes to the third input of the logic circuit AND 13 After the transient process in the electrometric amplifier is completed and the measurement limit is selected from the output of the waiting the multivibrator receives an enable signal to the second input of the logic circuit AND, then the emergency protection trigger overturns, causing the actuating relay of the emergency protection to trip, and an alarm signal is sent to the external circuits to reset the alarm Protection of nuclear reactor,. Thus, a nuclear reactor emergency protection device is more convenient and easy to maintain and provides automatic activation of the emergency signal to external circuits when an external signal is reached for the signal; 705903, 6 of this level, freeing the operation of the operator and control over the work of the prira from the need for continuous dialing.

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Claims (1)

POWER LEVEL EMERGENCY DEVICE DEVICE, containing an electrometric amplifier with a negative feedback block at the input and an emergency protection comparator, a power level adjuster connected to the second input of the emergency protection comparator, an emergency protection trigger connected to the executive relay indicator of measurement limits, it is noteworthy that, in order to increase the reliability of emergency protection and simplify maintenance, it is equipped with comparators of the upper and lower levels, input which are connected to the output of the electrometric amplifier, and the outputs to the control unit, the output of which is connected to a switching unit, consisting of a reversed shift register, a range encoder and an executive relay unit, as well as a protection signal generating unit, consisting of a standby multivibrator, input which is connected to the output of the upper level comparator, AND gate, a first input coupled to an output of the comparator emergency protection, the second input - to the output of _β zhdusche- mull ivibratora and third input via a logic OR circuit connected to outputs of logic block syem And, each first input of the logical AND circuits connected to the corresponding limit setting switch terminal, and each second input to the output of the encoder limits measuring. '' .1 ί 1 705903 2