RU2541857C1 - Method of finding faults in continuous dynamic system based on input of sample deviations - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: method comprises detecting the response of a non-faulty system on an interval at control points and determining and recording integral estimates of output signals of the system; determining and recording integral estimates of output signals of a model for each of the control points and each of the sample deviations; determining deformation of the integral estimates of output signals of the model; determining normalised deformation values of the integral estimates of output signals of the model; replacing the system with nominal characteristics with the inspected system, transmitting an analogue input signal to the input of the system, determining integral estimates of output signals of the inspected system; determining deviations of the integral estimates of output signals of the inspected system for control points from nominal values; determining normalised deviation values of the integral estimates of output signals of the inspected system; determining diagnostic features; determining a topological defect from the minimum value of the diagnostic feature.

EFFECT: broader functional capabilities of the method owing to search for topological defects.

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Description

The invention relates to the field of monitoring and diagnosing automatic control systems and their elements.

A known method for troubleshooting a dynamic unit in a continuous system (Method for troubleshooting a dynamic unit in a continuous system: RF patent 2429518: IPC ⁷ G05B 23/02 (2006.01) / Shalobanov SS - No. 201028421/08; claimed 08.07.2010; published on September 20, 2011, Bull. No. 26).

The disadvantage of this method is that it allows you to find only malfunctions in the form of deviations of the parameters of the transfer function of the system.

The closest technical solution (prototype) is a method for finding a faulty block in a dynamic system (Method for finding a faulty block in a dynamic system: RF patent 2435189: IPC ⁷ G05B 23/02 (2006.01) / Shalobanov S.V., Shalobanov S.S. - No. 2009123999/08; claimed 23.06.2009; published on 11.27.2011, bull. No. 33).

The disadvantage of this method is that it allows you to find only malfunctions in the form of changes in the transfer functions of individual blocks (subsystems) of the entire system.

The technical problem to which this invention is directed is to expand the functionality of the method associated with the search for topological defects, that is, defects that lead to a break or the appearance of new inter-unit connections.

путем подачи на первые входы k блоков перемножения сигналов системы управления, на вторые входы блоков перемножения подают экспоненциальный сигнал ℮^-αt, выходные сигналы k блоков перемножения подают на входы k блоков интегрирования, интегрирование завершают в момент времени Т_К, полученные в результате интегрирования оценки выходных сигналов F_jном(α), j=1, …, k регистрируют, определяют интегральные оценки выходных сигналов модели для каждой из k контрольных точек, полученные в результате введения пробных отклонений топологических состояний каждой из m возможных связей (удаляется существующая межблочная связь или вводится новая межблочная связь), для чего поочередно для каждой возможной топологической связи динамических блоков системы вводят пробное отклонение состояния топологической связи и находят интегральные оценки выходных сигналов системы для параметра α и входного сигнала x(t), полученные в результате интегрирования оценки выходных сигналов для каждой из k контрольных точек и каждого из m пробных отклонений P_ji(α), j=1, …, k; i=1, …, m регистрируют, определяют деформации интегральных оценок выходных сигналов модели, полученные в результате пробных отклонений состояний соответствующих топологических связей блоков динамической системы ΔP_ji(α)=P_ji(α)-F_jном(α), j=1, …, k; i=1, …, m, определяют нормированные значения деформаций интегральных оценок выходных сигналов модели, полученные в результате пробных отклонений состояний соответствующих топологических связей из соотношения $$\Delta {\widehat{P}}_{ji}\left(\alpha \right)=\frac{\Delta P_{ji}\left(\alpha \right)}{\sqrt{{\displaystyle \sum _{n=1}^k\Delta P_{ni}^2\left(\alpha \right)}}}$$

, замещают систему с номинальными характеристиками контролируемой, на вход системы подают аналогичный входной сигнал x(t), определяют интегральные оценки выходных сигналов контролируемой системы для k контрольных точек F_j(α), j=1, …, k для параметра α, определяют отклонения интегральных оценок выходных сигналов контролируемой системы для k контрольных точек от номинальных значений ΔF_j(α)=F_j(α)-F_jном(α), j=1, …, k, определяют нормированные значения отклонений интегральных оценок выходных сигналов контролируемой системы из соотношения $$\Delta {\widehat{F}}_j\left(\alpha \right)=\frac{\Delta F_j\left(\alpha \right)}{\sqrt{{\displaystyle \sum _{n=1}^k\Delta F_n^2\left(\alpha \right)}}}$$

, определяют диагностические признаки из соотношения $$J_i=1-{\left[{\displaystyle \sum _{j-1}^k\Delta {\widehat{P}}_{ji}\left(\alpha \right)\cdot \Delta {\widehat{F}}_j\left(\alpha \right)}\right]}^2$$

i=1, …, m, по минимуму диагностического признака определяют топологический дефект.The problem is achieved by registering the reaction of a known-good system f _jn (t), j = 1, ..., k on the interval t∈ [0, T _K ] at k control points and determine the integral estimates of the output signals F _jn (α), j = 1, ..., k of the system, for which, at the time of input of the input signal to the input of the system with nominal characteristics, the integration of the control system signals at each of k control points with weights ℮ ^-αt starts ^{at the} same ^time , where $$\alpha =\frac{5}{T_{\mathrm{TO}}}$$

by applying the control system signals to the first inputs k of the multiplication blocks, the exponential signal ℮ ^{-αt is} supplied to the second inputs of the multiplying blocks, the output signals of the multiplying blocks are fed to the inputs of the integration blocks k, the integration is completed at time T _K , obtained by integrating the output estimates _jnom signals F (α), j = 1, ..., k register define integral estimates signals output pattern for each of the control points k resulting from administration of test deviations topological comprising each of the m possible links (the existing interblock connection is deleted or a new interblock connection is introduced), for which, for each possible topological connection of the dynamic blocks of the system, a test deviation of the topological connection state is introduced and integral estimates of the system output signals for parameter α and input signal x are found ( t) obtained by integrating the estimates of the output signals for each of k control points and each of m test deviations P _ji (α), j = 1, ..., k; i = 1, ..., m register, determine the deformation of the integral estimates of the model output signals obtained as a result of test deviations of the states of the corresponding topological connections of the blocks of the dynamic system ΔP _ji (α) = P _ji (α) -F _jnom (α), j = 1 , ..., k; i = 1, ..., m, determine the normalized strain values of the integral estimates of the model output signals obtained as a result of trial deviations of the states of the corresponding topological relationships from the relation $$\Delta {\widehat{P}}_{ji}\left(\alpha \right)=\frac{\Delta P_{ji}\left(\alpha \right)}{\sqrt{{\displaystyle \sum _{n=\mathrm{one}}^k\Delta P_{ni}^2\left(\alpha \right)}}}$$

, replace the system with the nominal characteristics of the controlled one, apply the same input signal x (t) to the input of the system, determine the integrated estimates of the output signals of the controlled system for k control points F _j (α), j = 1, ..., k for the parameter α, determine the deviations integral estimates of the output signals of the controlled system for k control points from the nominal values ΔF _j (α) = F _j (α) -F _jn (α), j = 1, ..., k, determine the normalized values of the deviations of the integrated estimates of the output signals of the controlled system from the ratio $$\Delta {\widehat{F}}_j\left(\alpha \right)=\frac{\Delta F_j\left(\alpha \right)}{\sqrt{{\displaystyle \sum _{n=\mathrm{one}}^k\Delta F_n^2\left(\alpha \right)}}}$$

, determine the diagnostic signs from the ratio $$J_i=\mathrm{one}-{\left[{\displaystyle \sum _{j-\mathrm{one}}^k\Delta {\widehat{P}}_{ji}\left(\alpha \right)\cdot \Delta {\widehat{F}}_j\left(\alpha \right)}\right]}^2$$

i = 1, ..., m, the topological defect is determined by the minimum of a diagnostic feature.

Thus, the proposed method for finding a faulty topological connection of blocks is reduced to performing the following operations:

1. As a dynamic system, consider a system consisting of randomly connected dynamic blocks, with the number of considered changes in the topological connections of blocks m.

2. Pre-determine the control time T _to ≥T _PP , where

T _PP - the transition process of the system. The transient time is estimated for the nominal values of the parameters of the dynamic system.

.3. Determine the parameter of the integral signal conversion from the ratio $$\alpha =\frac{5}{T_{\mathrm{TO}}}$$

.

4. Fix the number of control points k.

деформаций интегральных оценок выходных сигналов модели, полученные в результате пробных отклонений состояний топологических связей блоков каждой из m топологических связей блоков для номинальных состояний топологических связей блоков и определенного выше параметра α, для чего выполняют пункты 6-10.5. Predefined normalized vectors $$\Delta {\widehat{P}}_i\left(\alpha \right)$$

deformations of the integral estimates of the model output signals obtained as a result of trial deviations of the states of the topological links of the blocks of each of the m topological links of the blocks for the nominal states of the topological links of the blocks and the parameter α defined above, for which points 6–10 are fulfilled.

6. The input signal x (t) (unit step, linearly increasing, rectangular pulse, etc.) is fed to the input of a control system with nominal characteristics. The proposed method does not provide fundamental restrictions on the type of input test exposure.

, для чего сигналы системы управления подают на первые входы k блоков перемножения, на вторые входы блоков перемножения подают экспоненциальный сигнал ℮^-αt, выходные сигналы k блоков перемножения подают на входы к блоков интегрирования, интегрирование завершают в момент времени Т_К, полученные в результате интегрирования оценки выходных сигналов F_jном(α), j=1, …, k регистрируют.7. The reaction of the system f _jnom (t), j = 1, ..., k on the interval t∈ [0, T _K ] at k control points is _recorded and the integral estimates of the output signals F _jnom (α), j = 1, ..., are determined k system. For this, at the moment of supplying the test signal to the input of the control system with nominal characteristics, the integration of the control system signals at each of k control points with weights ℮ ^-αt starts ^{simultaneously} $$\alpha =\frac{5}{T_{\mathrm{TO}}}$$

why the control system signals are fed to the first inputs of the multiplication units, the exponential signal ℮ ^{-αt is} supplied to the second inputs of the multiplication units, the output signals of the multiplication units are fed to the inputs of the integration units, the integration is completed at time T _K , obtained by integration estimates of the output signals F _jnom (α), j = 1, ..., k are recorded.

8. The integral estimates of the model output signals for each of the k control points are determined, obtained as a result of each of the m test deviations of the states of topological connections, for which the state of each topological connection of the blocks of the dynamic system is alternately changed (for example, from the “there is a connection” state to the “no” state communication ”or vice versa) and perform steps 6 and 7 for the same input signal x (t). The estimates of the output signals obtained as a result of integration for each of k control points and each of m test deviations P _ji (α), j = 1, ..., k are recorded.

9. The deformations of the integral estimates of the model output signals obtained as a result of trial deviations of the states of the topological connections of the blocks of the dynamic system ΔP _ji (α) = P _ji (α) -F _jnom (α), j = 1, ..., k; i = 1, ..., m.

.10. The normalized strain values of the integral estimates of the model output signals obtained as a result of test deviations of the states of the corresponding topological links of the blocks are determined by the formula $$\Delta {\widehat{P}}_{ji}\left(\alpha \right)=\frac{\Delta P_{ji}\left(\alpha \right)}{\sqrt{{\displaystyle \sum _{n=\mathrm{one}}^k\Delta P_{ni}^2\left(\alpha \right)}}}$$

.

11. Replace the system with the rated characteristics controlled. A similar test signal x (t) is supplied to the system input.

12. Determine the integral estimates of the output signals of the controlled system for k control points F _j (α), j = 1, ..., k, performing the operations described in paragraphs 6 and 7 with respect to the controlled system.

13. The deviations of the integrated estimates of the output signals of the controlled system for k control points from the nominal values ΔF _j (α) = F _j (α) -F _jnom (α), j = 1, ..., k are _determined .

.14. The normalized values of the deviations of the integrated estimates of the output signals of the controlled system are calculated by the formula $$\Delta {\widehat{F}}_j\left(\alpha \right)=\frac{\Delta F_j\left(\alpha \right)}{\sqrt{{\displaystyle \sum _{n=\mathrm{one}}^k\Delta F_n^2\left(\alpha \right)}}}$$

.

, i=1, …, m.15. Calculate the diagnostic signs of a faulty unit by the formula $$J_i=\mathrm{one}-{\left[{\displaystyle \sum _{j-\mathrm{one}}^k\Delta {\widehat{P}}_{ji}\left(\alpha \right)\cdot \Delta {\widehat{F}}_j\left(\alpha \right)}\right]}^2$$

, i = 1, ..., m.

16. At a minimum, the values of a diagnostic feature determine a topological defect.

Consider the implementation of the proposed method for searching for a topological defect for a system whose structural diagram is shown in the figure (see. Fig. The structural diagram of the diagnostic object).

Transfer functions of blocks:

; $$W_2=\frac{k_2}{T_{2}p+1}$$

; $$W_3=\frac{k_3}{T_{3}p+1}$$

, $$W_{\mathrm{one}}=\frac{k_{\mathrm{one}}\left(T_{\mathrm{one}}p+\mathrm{one}\right)}{p}$$

; $$W_2=\frac{k_2}{T_{2}p+\mathrm{one}}$$

; $$W_3=\frac{k_3}{T_{3}p+\mathrm{one}}$$

,

nominal values of parameters: T ₁ = 5 s; k ₁ = 1; k ₂ = 1; T ₂ = 1 s; k ₃ = 1; T ₃ = 5 s. When searching for a topological defect in the form of a break in the connection between the first and second links (defect No. 1) by applying a step test input signal of unit amplitude and integral signal conversion for parameter α = 0.5 and T _k = 10 s, the values of diagnostic signs are obtained based on trial deviations of states topological connection using three control points located at the outputs of the blocks: J ₁ = 0; J ₂ = 0.7499 (disconnection between the second and third block); J ₃ = 0.7847 (disconnection between the third and first block). The minimum value of the sign J ₁ unambiguously indicates the presence of a topological connection between the first and second blocks.

Modeling of the processes of searching for topological defects of the links between the second and third, as well as the third and first blocks for a given diagnostic object with the same integration parameter α and with a single step input signal gives the following values of diagnostic signs:

In the presence of a defect in the form of a break in the topological connection between the second and third blocks: J ₁ = 0.7499; J ₂ = 0; J ₃ = 0.0704.

In the presence of a defect in the form of a break in the topological connection between the third and first blocks: J ₁ = 0.7847; J ₂ = 0.0704; J ₃ = 0.

The minimum value of a diagnostic sign in all cases correctly indicates the presence of a topological defect.

Claims (1)

A method for troubleshooting in a continuous dynamic system based on the introduction of test deviations, based on the fact that the number of possible malfunctions is fixed m, the monitoring time T _K ≥T _{PP is} determined, where T _PP is the transient time of the system, the integral signal conversion parameter is determined from the relation

, use the test signal in the interval t∈ [0, T _K ], use the integral signal estimates obtained for real values of the integral transformation parameter α as the dynamic characteristics of the system, fix the number k of control points of the system, record the reaction of the diagnostic object f _j (t) , j = 1, ..., k and the reaction of a known good system f _jnom (t), j = 1, ..., k on the interval t∈ [0, T _K ] at k control points, determine the integral estimates of the output signals f _jnom (α ), j = 1, ..., k of a working system, for which, at the time of the test signal input systems with nominal characteristics simultaneously begin integration control system signals in each of the control points k with weights

where

by applying the control system signals to the first inputs of k multiplying blocks, an exponential signal is supplied to the second inputs of the multiplying blocks

, the output signals k of the multiplication units are fed to the inputs of the integration blocks k, the integration is completed at time T _K , obtained by integrating the estimates of the output signals F _jn (α), j = 1, ..., k are recorded, replace the system with the nominal characteristics of the controlled, at the system input is fed the same test signal x (t), define the integral evaluation system controlled signals to control points k F _j (α), _j = 1, ..., k to the parameter α, is determined deflection of integral controlled system signals to ratings for k ntrolnyh points ΔF _j from the rated value _{(α) = F j (α} ) -F _jnom (α), j = 1, ..., k, determine the normalized integral value of deviations of the signal ratio controlled system estimates

characterized in that the integral estimates of the output signals of the model for each of the k control points are determined, obtained as a result of each of the m test deviations of the states of topological links, for which the state of each topological connection of the blocks of the dynamic system is alternately changed and the integral estimates of the system output signals are found for the parameter α and the input signal x (t) obtained by integrating the estimates of the output signals for each of the k control points and each of the m test deviations of the topological state ogicheskoy communication P _ji (α), j = 1, ..., k; i = 1, ..., m register, determine the deformation of the integral estimates of the model output signals obtained as a result of test deviations of the states of the corresponding topological connections of the dynamic blocks of the system ΔP _ji (α) = P _ji (α) -F _jnom (α), j = 1 , ..., k; i = 1, ..., m, determine the normalized strain values of the integral estimates of the model output signals obtained as a result of trial deviations of the states of the corresponding topological links of the blocks from

, determine the diagnostic signs from the ratio

, at the minimum of a diagnostic sign, a topological defect is determined.

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