SU1103240A1 - Majority-reserved device having controllable structure - Google Patents

Description

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4: The invention relates to the field of digital automation and computer technology and can be used in automatic process control devices of increased reliability. A known redundant device with a controlled structure that contains three redundant logic blocks and three controlled major elements, whose information inputs are connected to redundant logic blocks, and the control inputs are with a common control bus of the device i. The disadvantage of this device is low testability: the operability of controlled major elements cannot be tested when monitoring a device both when it is used autonomously and when for increased reliability A number of redundant devices with a managed structure include a cascade, thereby forming a network voting scheme. This is due to the fact that when the device is operating in the voting mode, the same-named signals are received from all logical inputs of controlled majority elements from logical blocks. Due to this, a number of defects of controlled major elements, for example, the repetition of the signal of one of the logical blocks is not detected. A known redundant device with a controlled structure, containing three redundant logic blocks, three AND elements and three controlled major elements, the inputs of the backup logical blocks connected to the device inputs, and their outputs connected to the AND elements with the information inputs of the controlled majority elements, the control inputs of which are connected to the control bus of the device, and the outputs of the controlled majority elements connected to the outputs of the device, the second inputs, elements They are connected to the device blocking bus 2. This device, when used offline, i.e. In the case when it is possible to supply test signals directly to the device inputs, it ensures the operability of the first elements to be controlled by the majority. However, the number of cycles of control of the known device is excessively large, which makes the verification procedure longer. In addition, in the case when the number of major-redundant devices with a controlled structure is cascaded, the device's testability is impaired: the operability of controlled major elements in the voting mode in all stages except the first one cannot be verified. This is explained by the fact that the inputs of each of the cascade-connected devices / devices are connected to the outputs of the device of the previous stage and the test signals for it are the output signals of the device of the previous stage. When a serviceable device operates in control cycles, in which two of the three elements of And have a blocking signal O, the output signal is absent on all outputs of the device, thereby not providing a subsequent cascade of test signals and thus excluding the possibility of checking all stages in these cycles, except first. As a result, a number of major element defects in all recovery stages except the first, for example, repetition of the signal from one of the reserved blocks, is not detected. The aim of the invention is to improve the testability of the device when cascading several major-redundant devices with a controlled structure. This goal is achieved by the fact that a major-redundant device with a controlled structure contains three redundant blocks; the inputs are connected to the corresponding inputs of the device, the first three I elements, the first inputs of which are connected to the outputs of the reserved blocks, the second inputs to the device lock bus, and three controllable majority elements whose control inputs are connected to the device control bus, and the outputs with the device outputs, contains the element NOT, the three second elements AND, and the three elements OR, the first inputs of which are connected respectively to the outputs of the first elements AND the outputs, to the information inputs of the controlled majority lementov, the second input - to the outputs of the second AND gate, first inputs of which are connected to the device enumeration tires second inputs - with the output of NOT circuit whose input is connected to the locking device bus. Diagram of the device shown in the drawing. The device contains inputs 1-3, blocking bus 4, brute-force buses 5-7, control bus 8, redundant blocks 9-11, element NOT 12, first .13-15 and second 16-18 elements AND, elements OR 19-21 , controlled majority elements 22-24 and outputs 25-27. The inputs of the reserved blocks 9-11 connected to the inputs of the device 1-3, and their outputs with the first inputs of the first. output elements and 13-15. The second inputs of the And 13-15 elements are connected to the blocking bus 4. The outputs of the first And 13-15 elements are connected to the first inputs of the OR 19-21 elements, the second inputs of which are connected to the outputs of the second And 16-18 elements, and the outputs to the information inputs controlled material grades 22-24. The first inputs of the second elements AND 16-18 are connected to the inputs of the search 5-7, and their second inputs through the HE 12 are connected to the blocking bus 4. The control inputs of the controllable major elements are connected to the control bus 8 of the device. The proposed device allows operation in the following three modes: normal operation; linear verification of redundant blocks; checks of majoritarian elements. In the first mode, the i- signal on lock 4 block allows the passage of signals from redundant 911 blocks through AND 13-15 elements. The output signals of the latter through the elements OR 19-21 arrive at the information inputs of the controlled majority elements 22-24. Simultaneously, the signal inverted by the element NOT 12 prohibits the passage of the brute force signals from the tires 5–7 through the second elements AND 16–18. Thus, the presence of elements And 13-15, the second elements And 16-18 and elements OR 19-21 does not affect in any way the passage of signals from redundant blocks to the information inputs of the controlled majority elements. On the control bus 8 of the device, there is a signal corresponding to the operation of the controlled majority elements in the heading mode. In the linear check mode of the blocks being repaired, the operation of the listed nodes does not differ from their operation in the first mode. The difference between these modes is that on the control bus 8 a signal O is set, which corresponds to the operation of the controlled majority elements in the linear mode, i.e. in the repeater mode: controlled major element 22 repeats the output signal of logic block 9, passed AND 13 and OR 19 elements; the controlled majoritarian element 23 repeats the signal of the logical unit 10., passed through the elements of AND 14 and OR 20; controlled major element 24 repeats the signal of logic block 11, passed elements AND 15 and OR 21. Thus, in the second mode, the signals at the outputs of the device repeat the output signals of the corresponding redundant block, thereby ensuring the conditions of the performance check of the latter by applying to the inputs 1-3 test signals and comparison with the reference signals at the outputs 25-27. In the third mode of operation, the lock 4 bus sends a signal O. This signal prevents the output signals of logic blocks 9-11 from passing through the first AND 13-15 elements. At the same time, the signal i from the output of the element NOT 12 permits the passage of the enumeration signals from the buses 5-7 through the second elements AND 16-18 and the elements OR 19-21 to the information inputs of the controlled majority elements 22-24, applying to the buses 5-7 Various sets of brute-force signals and control at outputs 25-27 of the response to these signals — controllable majority elements 22–24; you can fully test the performance of the latter in the majority mode and in the Repeater mode. The values of the control signals at inputs 4–8 and the response of the monitored device to them are listed in the table. When operating a number of proposed devices in a system with multiple majority restoration of a tire, 4 to 8 of all cascades are combined. In this case, in the first mode, the operation of the device corresponds to that described above; in the second mode, the logical blocks of all cascades are connected to three independent, independently tested channels / in the third mode, the controlled majority elements of all cascades are checked simultaneously and independently from each other, which is ensured by parallel input of their sets of brute-force signals to their inputs output signals. The proposed device has wider functionality, since it provides the possibility of a complete check of both redundant logic blocks and controlled majority elements, regardless of whether the device is autonomous or included as one of the cascades in a redundant system with multiple majority restoration.

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Claims (1)

the inputs of which are connected to the control bus of the device, and the outputs are the outputs of the device, characterized in that, in order to increase the control suitability of the device when cascading several major redundant devices with a controlled structure, it contains an element NOT, three second AND elements, and three OR elements, the first inputs of which are connected respectively with the outputs of the first AND elements, the outputs with the information inputs of controlled majority elements, the second inputs with the outputs of the second AND elements, the first inputs of which s connected to shina- _Λ E sorting device, second vho- § yes - to output of NOT circuit whose input is connected to the bus lock apparatus f *