RU2467372C1 - Device for switching channels of triplex control system - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: invention relates to automated process control systems, particularly ground tests of space rocket equipment. The device for switching channels of a triplex control system has in each standby control system channel a unit for analysing information exchange, connected to neighbouring units by inputs/outputs and which forms therein and in AND circuits and inverters which form an automatic logic machine a malfunction symptom of one of them, which is detected during analysis of real-time exchanged information. Output signals of the automatic machine, which realises a truth diagram, in accordance with which peripheral device control buses are switched by driver buses, are connected to the right of the faulty channel of the control signal. In an operating state of the system, said buses are connected to input/output interfaces of like channels.

EFFECT: high reliability of a triplex control system.

1 dwg

Description

The invention relates to automated control systems for technological processes, in particular ground tests of liquid rocket engines, propulsion systems of spacecraft and blocks of launch vehicles.

Stands for testing complex and expensive rocket and space technology (RKT) products are equipped with highly reliable redundant three-channel control systems for fire and explosive technological processes for the preparation and conduct of their testing. The choice of this backup method is largely related to its use also in standard control systems of launch vehicles and spacecraft, with devices of which the stand-by control system must be interfaced. At the same time, tripling in control systems ensures the maximum speed of the control system by switching channels with combinational logic circuits. High performance is one of the main requirements for the testing system for RCT products.

During the normal failure-free operation of the triple control system, the programmable logic controller of each channel during one repeating cycle of operation sequentially polls the discrete inputs, aligns their values by majorizing with the values of the inputs of the same name in the other two channels, arriving on the information exchange buses between the channels, processing information on given algorithms with the formation of output values, aligning the values of the last and intermediate variables with using the same operation described above and outputting the pin values via the input-output interface to the output devices, which, through majorization schemes 2 of 3, generate signals to the electric drives and electric fuses of the actuating elements.

At the same time, in control systems of the described type, the problem arises of parrying the failures of the most complex and unique system elements, programmable logic controllers, with minimal loss of reliability.

The closest known technical solution to this problem by purpose is a channel switching scheme in an automated redundant control system for refueling a cryogenic booster unit (see Russian Federation Patent No. 2084011, IPC G05B 9/03, 1995), containing three system channels in programmable logic controllers control, respectively, the first, second and third blocks of analysis of exchange information, the first and second inputs and outputs of the first of which are connected respectively with the second input-output of the third and ervym input-output of the second one, the second input-output of which is connected to the first input-output of the third block of information exchange analysis.

In this system, in good condition, information from the controllers is transmitted to the next level via the local area network of the first channel, in case of a malfunction of the first channel, via the local network of the second channel, etc.

The disadvantage of this technical solution is the complicated logic of the peripheral devices connected to the output local area networks of the channels, since each of them must provide the circuitry for switching to a working channel. The final result of the complexity of the schemes is certainly a decrease in the overall reliability of the control system.

The technical problem solved by the invention is to increase the reliability of the redundant control system of the test bench for rocket and space technology.

This is achieved by the fact that in the known device for switching channels of a triple control system, containing in the programmable logic controllers of the three channels of the control system, respectively, the first, second and third blocks of analysis of exchange information, the first and second inputs and outputs of the first of which are connected respectively to the second input-output the third and first input-output of the second of them, the second input-output of which is connected to the first input-output of the third unit of analysis of exchange information, according to the invention in о the first, second, third, fourth, fifth and sixth “I” circuits were introduced, the first three of which have inverse outputs, the first, second and third inverters, as well as the first, second, third, fourth, fifth and sixth bus drivers, the third , the fourth, fifth and sixth outputs of the first exchange information analysis unit are connected respectively to the third input of the third exchange information analysis unit, the fourth input of the second exchange information analysis unit, the first input of the third AND circuit and the second input of the first AND circuit, the third, fourth , P the fourth and sixth outputs of the second exchange information analysis unit are connected respectively to the third input of the first exchange information analysis unit, the fourth input of the third exchange information analysis unit, the first input of the first “I” circuit and the second input of the second “I” circuit, the third, fourth, fifth and the sixth outputs of the third exchange information analysis unit are connected respectively to the third input of the second exchange information analysis unit, the fourth input of the first exchange information analysis unit, the first input of the second “I” circuit and the second by the third input of the third circuit “And”, the output of the first circuit “And” is connected to the third input of the second circuit “And”, with the second input of the fourth circuit “And” and the first input of the fifth circuit “And”, the output of the second circuit “And” is connected to the third input of the third circuit “And”, with the second input of the fifth circuit “And” and the first input of the sixth circuit “And”, the output of the third circuit “And” is connected to the third input of the first circuit “And”, with the second input of the sixth circuit “And” and with the first input of the fourth AND circuit, the output of which is connected to the control input of the fourth bus driver and the input of the second invert RA, the output of which is connected to the control input of the second bus driver, the information input of which is connected to the I / O interface of the programmable logic controller of the second channel of the control system, and the information output is connected to the information input of the fifth bus driver, the information output of the fourth bus driver and to the bus of the second a communication channel with peripheral devices, the output of the fifth AND circuit is connected to the control input of the fifth bus driver and the input of the third inverter, you the path of which is connected to the control input of the third bus driver, the information input of which is connected to the input / output interface of the programmable logic controller of the third channel of the control system, and the information output is connected to the information input of the sixth bus driver, the information output of the fifth bus driver and the third channel of communication with peripheral devices, the output of the sixth circuit “AND” is connected to the control input of the sixth bus driver and the input of the first inverter, the output to which is connected to the control input of the first bus driver, the information input of which is connected to the I / O interface bus of the programmable logic controller of the first channel of the control system, and the information output is connected to the information input of the fourth bus driver, the information output of the sixth bus driver and to the bus of the first communication channel with peripheral devices.

The drawing shows a diagram of a device for switching channels of a triple control system.

The device contains, as part of programmable logic controllers, the three channels of the control system, respectively, the first 1-1, second 1-2 and third 1-3 blocks of analysis of exchange information. The first and second inputs and outputs of the first block of analysis of exchange information 1-1 are connected respectively with the second input-output of the third 1-3 and with the first input-output of the second 1-2 of them, the second input-output of which is connected to the first input-output of the third 1-3 signal blocks of the exchange information.

The third, fourth, fifth and sixth outputs of the first 1-2 units of analysis of exchange information are connected respectively with the third input of the third 1-3 units of analysis of exchange information, the fourth input of the second 1-2 units of analysis of exchange information, the first input of the third 2-3 of the circuit “And "And the second input of the first 2-1 circuit" AND ".

The third fourth, fifth and sixth outputs of the second 1-2 units of analysis of exchange information are connected respectively to the third input of the first 1-1 unit of analysis of exchange information, the fourth input of the third 1-3 unit of analysis of exchange information, the first input of the first 2-1 of the “And” circuit and the second input of the second 2-2 circuit "AND".

The third, fourth, fifth and sixth outputs of the third 1-3 units of analysis of exchange information are connected respectively with the third input of the second 1-2 units of analysis of exchange information, the fourth input of the first 1-1 unit of analysis of exchange information, the first input of the second 2-2 of the circuit “And "And the second input of the third 2-3 circuit" AND ".

The output of the first 2-1 circuit “AND” is connected to the third input of the second 2-2 circuit “AND”, the second input of the fourth 2-4 circuit “AND” and the first input of the fifth 2-5 circuit “AND”. The output of the second 2-2 circuit “AND” is connected to the third input of the third 2-3 circuit “AND”, the second input of the fifth 2-5 circuit “AND” and the first input of the sixth 2-6 circuit “AND”. The output of the third 2-3 circuit “And” is connected to the third input of the first 2-1 circuit “And”, the second input of the sixth 2-6 circuit “And” and the first input of the fourth 2-4 circuit “And”.

The output of the fourth 2-4 circuit "And" is connected to the control input of the fourth 4-4 bus driver and the input of the second 3-2 inverter, the output of which is connected to the control input of the second 4-2 bus driver.

The output of the fifth 2-5 circuit “AND” is connected to the control input of the fifth 4-5 bus driver and the input of the third 3-3 inverter, the output of which is connected to the control input of the third 4-3 bus driver.

The output of the sixth 2-6 circuit “And” is connected to the control input of the sixth 4-6 bus driver and the input of the first 3-1 inverter, the output of which is connected to the control input of the first 4-1 bus driver.

The information inputs of the first 4-1, second 4-2 and third 4-3 bus drivers are connected respectively to the input / output interface buses of the programmable logic controllers of the first, second and third channels of the control system.

The information output of the first bus driver 4-1 is connected to the bus of the first communication channel with peripheral devices of the control system, the information input of the fourth bus driver 4-4 and the information output of the sixth bus driver 4-6. The information output of the second bus driver 4-2 is connected to the bus of the second communication channel with peripheral devices, the information input of the fifth bus driver 4-5 and the information output of the fourth bus driver 4-4. The information output of the third bus driver 4-3 is connected to the bus of the third communication channel with peripheral devices, the information input of the sixth bus driver 4-6 and the information output of the fifth bus driver 4-5.

The device operates as follows.

When all three programmable logic controllers are operational, the fifth and sixth outputs of the analysis blocks of the exchange information 1-2, 1-2, and 1-3 generate signals of the zero logic level, respectively, on the inverse outputs of the I circuits 2-1, 2- used in the device 2 and 2-3 and the direct outputs of the “I” circuits 2-4, 2-5 and 2-6 are signals of a single logical level, which, respectively, through inverters 3-1, 3-2 and 3-3, provide connection with logic signals of zero level supplied to the control inputs of the bus drivers 4-1, 4-2 and 4-3, respectively n input-output of programmable logic controllers for the same bus of communication with peripheral devices from the outputs of bus drivers 4-1, 4-2 and 4-3. At the same time, the outputs of the And circuits 2-4, 2-5, and 2-6 set the signals that disable their outputs at the control inputs of the bus drivers 4-4, 4-5, and 4-6.

Fending off the consequences of a failure of one of the programmable logic controllers in this device consists in switching to work from one of the remaining two operational ones. This is due to the fact that the reliability of simultaneously operating controllers with peripherals organized by majority logic is two times lower than that of a single controller. Switching to another procedure for synchronizing and switching channels when testing rocketry simply does not have the necessary reserve of time.

The device diagram is symmetrical with respect to the channels, so it is enough to consider the operation of the device in case of failure of one of the programmable logic controllers. The fact of failure is detected during the implementation of the above procedure for synchronizing the operation of the channels of the control system by aligning changing information in the memory of programmable logic controllers in each cycle when it is exchanged between the latter through the first and second inputs and outputs of the exchange information analysis blocks 1-1, 1-2 and 1-3. A sign of normal operation of neighboring programmable logic controllers can be, for example, a comparison of the length of the received file with a given value.

In the event of a failure of the programmable logic controller, for example, in the third channel of the control system, the exchange information analysis unit 1-1 generates a signal at its third output informing the exchange information analysis unit 1-2 through the third input about the decision made on the failure of the third channel of the control system. Similarly, the functioning unit for analyzing the exchange information 1-2 generates a signal about the failure of the third channel at the fourth output, which is transmitted to the third input of the analysis unit for exchange information 1-1. As a result, at the sixth output of the exchange information analysis unit 1-1 and at the fifth output of the exchange information analysis unit 1-2, single logical signals are generated.

Zero signal levels at the fifth output of the first 1-1 and at the sixth output of the second 1-2 units of analysis of exchange information determine unit values at the outputs (inverse) of the second 2-2 and third 2-3 “I” circuits. In turn, the single outputs of the last “And” circuit of the sixth output of the first 1-1 exchange analysis unit and the fifth output of the second 1-2 exchange information analysis unit determine the zero signal level at the output (inverse) of the first 2-1 “And” circuit.

The indicated values of the outputs of the circuits "And" 2-1, 2-2 and 2-3 determine in turn at the outputs of the circuits "And" 2-4, 2-5 and 2-6 the logical signals "zero", "zero" and " unit ", respectively.

A single signal at the output of the And circuit 2-6 through the inverter 3-1 determines the zero signal at the control input of the bus driver 4-1, through which the signals from the I / O interface bus of the programmable logic controller of the first channel of the control system are transmitted to the bus of the first communication channel with peripheral devices and to the input of the bus driver 4-4, which is also turned on, since a zero signal from the output of the And circuit 2-4 is supplied to its control input. Through the open bus driver 4-4, the signals of the I / O interface bus of the programmable logic controller of the first channel also go to the bus of the second communication channel with peripheral devices and to the input of the bus driver 4-5, which is also open by a zero signal at its control input coming from the output “I” circuits 2-5, which also ensures the transmission of I / O signals of the programmable logic controller of the first channel to the bus of the third communication channel with peripheral devices. The single signals at the output of the And circuit 2-6 provide the closed state of the bus driver 4-6, and the single values of the signals at the outputs of the inverters 3-2 and 3-3 provide the closed state of the bus drivers 4-2 and 4-3, which thus do not interfere with the operation of the device in the described case of a malfunction in the control system.

If the second channel fails, the device connects the signals of the third channel to the outputs, and if the first channel fails, the signals of the second channel.

Improving the reliability of the triple control system is provided by the described technical solution due to the fact that in the circuitry of peripheral devices it is not necessary to take into account the described failure options of the control system, which simplifies and accordingly increases their reliability. The peripheral devices together constitute the largest part of the electronics of the redundant control system for the test bench for rocket and space technology, so the reliability gain will be substantial.

Claims (1)

A device for switching channels of a triple control system, comprising, in programmable logic controllers of the three channels of the control system, respectively, the first, second and third blocks of analysis of exchange information, the first and second inputs and outputs of the first of which are connected respectively to the second input-output of the third and first input-output of the second of which, the second input-output of which is connected to the first input-output of the third unit of analysis of exchange information, characterized in that the first, second, third, even the fourth, fifth and sixth “I” circuits, the first three of which have inverted outputs, the first, second and third inverters, as well as the first, second, third, fourth, fifth and sixth bus drivers, the third, fourth, fifth and sixth outputs of the first the exchange information analysis unit are connected respectively to the third input of the third exchange information analysis unit, the fourth input of the second exchange information analysis unit, the first input of the third AND circuit and the second input of the first AND circuit, the third, fourth, fifth and sixth outputs of the second unit a exchange information analysis are connected respectively to the third input of the first exchange information analysis unit, the fourth input of the third exchange information analysis unit, the first input of the first “I” circuit and the second input of the second “I” circuit, the third, fourth, fifth and sixth outputs of the third exchange analysis unit information are connected respectively to the third input of the second exchange information analysis unit, the fourth input of the first exchange information analysis unit, the first input of the second AND circuit and the second input of the third AND circuit, output of the first circuit “And” is connected to the third input of the second circuit “And”, with the second input of the fourth circuit “And” and the first input of the fifth circuit “And”, the output of the second circuit “And” is connected to the third input of the third circuit “And”, with the second input of the fifth circuit “And” and with the first input of the sixth circuit “And”, the output of the third circuit “And” is connected to the third input of the first circuit “And”, with the second input of the sixth circuit “And” and with the first input of the fourth circuit “And” the output of which is connected to the control input of the fourth bus driver and the input of the second inverter, the output of which is connected to the control the measuring input of the second bus driver, the information input of which is connected to the input / output interface of the programmable logic controller of the second channel of the control system, and the information output is connected to the information input of the fifth bus driver, the information output of the fourth bus driver and to the bus of the second communication channel with peripheral devices, the output of the fifth AND circuit is connected to the control input of the fifth bus driver and the input of the third inverter, the output of which is connected to the control at the input of the third bus driver, the information input of which is connected to the input-output interface of the programmable logic controller of the third channel of the control system, and the information output is to the information input of the sixth bus driver, the information output of the fifth bus driver and the bus of the third communication channel with peripheral devices, output of the sixth circuit “AND” is connected to the control input of the sixth bus driver and the input of the first inverter, the output of which is connected to the control input of the first bus driver, information input is connected to the interface bus input-output programmable logic controller control system first channel and information output - to the data input of the fourth bus driver, the sixth data output bus driver and the first channel communication bus with peripherals.