**6. Description of the OCP by frequency components**

According to the SI-method, all available information about the OCP is monitored. First of all, the OCP is replaced by oscillatory circuits with the corresponding frequency components (FC), that is, from the HFC to the super-LFC (**Figure 7**). Low-quality contours, in which only one half-wave of oscillation develops, are also vibrational. It is known that in RPA and SCADA devices, input information is sampled by time in the ADC block. The sampling frequency of the ADC is selected based on the presence of the highest-frequency component in the OCP. So, the ADC block will fix in the input signal all the components with a lower natural frequency (i.e. all the LFCs). So with the well-known operator description of the OCP, *y(t) = W(D)\*x(t).* Constants in *W* with indices n and m describe the highest frequencies with which movements in the OCP are possible. We assume further that for the ADC, these constants *aN*, *bM* will be the initial *a0*, *b0*. Then all other frequencies in the new *W* will be slower; therefore *aN*, *bM* will be the slowest s-LFCs. This

**Figure 7.** *Equivalent structural scheme of GESOCP with division of movements by frequencies.*

allows us to provide a description of the OCP transfer function *W* for the highestfrequency component, which can be recorded by the ADC. You can control all the slow oscillatory circuits of the OCP. Very low-frequency motions may be present in the OCP. The lowest-frequency components and movements in the OCP can be considered informational (**Figure 7**).

This record allows you to highlight the presence of super-LFC in the OCP using the signals of emergency files of RPA devices. Such frequency components are generated in the OCP (**Figure 7**) by input shock effects of overvoltage, short circuit, OPG, operational switching, etc. Motions in super-LFC circuits of the OCP can be in different time ranges—second, monthly, annual and so on, for example, envelope industrial frequency response (e-LFC). e-LFC mathematically summarises signal circuits in OCP. s-LFC is only an information loop.

The OCP structure is represented by the GESOCP scheme in the common field of TS information sensors that recognise *SN* situations. Each *SN* is divided into elementary components—nonterminal components of NTS. Information components are controlled by a logical change in TS outputs. For example, the amplitude parameters of the signals of the OCP loops are monitored and represented by the corresponding TS. Each OCP oscillation circuit is controlled by RPA devices. Devices at a morphological hierarchical level will be further represented by a GESTS scheme with a *GTS* grammar (**Figure 9**).

Extending the discussion about the presence of information loops to the features of higher-frequency loops, we can separate the signal description of processes in the OCP from the information description of the essence of the processes. This implies the task of searching for vibrational components in the ranges of the LFCs of super-LFCs by means of analysis in CAD of the frequency components of the alarm file signals. Solving the problem of separating parametric and information loops will help fill the lack of information when recognising *SN* situations in OCP.

#### **7. Description of OCP equipment by information components**

It is proposed to implement the stable working of recognition devices based on an algorithm for the selective search (SP) for a sufficient amount of information to perform RPA functions. The amount of information is accumulated based on the control of a number of information components, for example, the type of damage, the steadiness of the development of damage, the location of the damage, the presence of selective and blocking signs for damaged and undamaged areas, the absence of extraneous semantic situations, etc.

Further, attention is paid to the formation of OCP grammar for the tasks of improving the algorithms of RPA devices. It is necessary to develop consistent structural trees of OCP and RPA with respect to the semantic signal *S(t)* as well as a method for the end-to-end mathematical description of transients in the 'network equipment-RPA devices' hierarchical chain in the automatic control system (**Figure 4**). This is part of the developed SI method.

The SI method is based on the application of sequential graphic transformations from a circuit diagram based on electrical parameters and the transition to a circuit based on information components. The structural-operator method is involved for the formal description of the OCP by parametric components [7]. Then the transition to the description of the SI method is carried out only by information components. The transition is performed by introducing terminal symbol sensors at the control points of the OCP scheme (**Figure 9**). In the internal OCP scheme, these can be imaginary points, since most of the structure of the OCP is not divided into control parts.

*Automatic Control of the Structure of Dynamic Objects in High-Voltage Power Smart-Grid DOI: http://dx.doi.org/10.5772/intechopen.91664*

For example, **Figure 8** shows the SO description in the form of electrical parameters of one of the elements of the OCP—transformer. Information flows are generated by inertial fields and are described by the operators *D = d/dt*, *1/D = S*. The input to the circuit is the coordinate of the perturbation signal *SN(t)* for OCP. According to the SI method, at each control point of the circuit, the output of the elementary transfer function must be monitored by the TS sensor with the corresponding weight coefficient. TS consists of a GESTS scheme. It includes a filter and a threshold element ρN. The TS acts as an observer for the operation of the structural-operator diagram of the OCP. Naturally, this is an imaginary and often unrealisable scheme in connection practice. But the implementation of such a solution is performed in CAD. This makes it possible to implement a theoretical description of the OCP scheme. In OCP, all TSs are combined into a more general S-filter, which generates the signal *SOCP(t)* and is controlled by the threshold ρN. Thus, a rigorous mathematical description of the OCP is feasible.

This allows you to build a mathematical model of OCP in CAD for the selective search algorithm SP to reach the maximum amount of information. Functional modelling in CAD will provide an additional amount. The passage of the informational components of the *SN* semantic situation through the structural-informational models of electrically connected equipment (**Figure 8**) of the OCP using the signals of real emergency files supplied by modern devices is simulated. If theoretically and practically received amount of information from real OCP is sufficient for recognition, then the problem is solved by practically recognisable algorithms. OCP is observed and controlled by recognition algorithms. If the theoretical amount of information is not sufficient for distinguishing *SN* and making decisions in particular cases or in the general case, then indirect methods of detecting errors in management are necessary.

#### **8. Representation of OCP by semantic components**

**GESOCP scheme description.** The structural tree of *SN*→TS formation for the OCP uses the internal coordinates and OCP contours not observed by the GESRPA device circuits (**Figure 9**). The construction of the GESOCP scheme proceeds from three foundations:


The OCP model is built on the basis of a bundle relative to the internal adder. In the IIR filter scheme, each rule *P* is assigned a weight coefficient *KN* or *KM* (**Figure 10**). In the structure of digital filters, the inertia is set discretely by the SyntA structural automaton, and the dynamic behaviour of the filters (their own transient process)

**Figure 9.**

*Structural schemes of ownership, prompted by the operator method.*

**Figure 10.**

*GESOCP scheme for dividing* SN *situations into elementary components of NTS.*

#### *Automatic Control of the Structure of Dynamic Objects in High-Voltage Power Smart-Grid DOI: http://dx.doi.org/10.5772/intechopen.91664*

depends on the information received from the input and from the output of the OCP circuit. The GOCP grammar differs from GRPA in (2, 3) in that its elements have an oscillatory, harmonic output, while GRPA elements have a threshold output.

**Separation of movements by frequencies:** The OCP representation is introduced as a description of the GOCP grammar, including a list of *SN* situations (root *S* characters). *SNs* are interconnected by the semantic rules of *PN* (**Figure 11**) and characterise the work of OCP. In turn, the *SNs* themselves are represented by semantic information components (terminal and nonterminal symbols) and the *PN* rules of their relationship. Thus, the lists of the grammar *G* and the GES schemes form the semantic model of OCP, composed of semantic components. The start and end vertex is the *SN* 'NM' situation.

By dividing the movements according to frequencies, we mean to clarify the number and parameters of the oscillatory circuits in the OCP (**Figure 7**). Based on the descriptions obtained by the structural-operator method [7], it is possible to represent the structure of the OCP definition tree in the form of the relationship of a number of oscillatory or inertial circuits (**Figures 7** and **9**). The method of dividing movements by frequencies from the point of view of the SI method is as follows.

According to the SI method, when frequency motions are divided, all the frequency circuits of the OCP are controlled [9–11]. If the selective GESRPA part (synchronous detector) controls one circuit (**Figure 7**), then the blocking part of the GESRPA monitors the other circuits. For information to appear in the slowest OCP loop, a series of events in the transition process must occur, and a sufficiently large amount of information should have accumulated. But the goal of the RPA is to minimise the development of events in the OCP. As a result of this, movement in super-slow circuits rarely occurs; the appearance of transient information in the OCP can be interrupted. This leads to the indicated conflicts 'a' to 'c'.

For the OCP scheme: (A) The number and parameters of the oscillatory circuits in the OCP are determined from the mathematical descriptions and signals of the emergency files (**Figures 7** and **8**). (B) An OCP is drawn up in the form of an IIR filter (**Figure 9**). (C) The GESOCP scheme is compiled in the form of an FIR filter as the inverse of the GESRPA scheme according to GOCP ≈ ΣGRPA relative to *ΔSN* (**Figure 10**). (D) The elements MorphA, SyntA and SemA stand

**Figure 11.** *Scheme of the 'GESOCP by the* SN *situation'. Shaping* SN *and signal situations* S(t)*.*

#### **Figure 12.**

*Tree scripting* SN *in dynamics by signal* S(t)*.*

out in GOCP and are implemented in separate computing parts. (E) *W*TABL is filled out to represent the OCP. Training and supervising samples of *SN* situations are formed.

Such a volume of simultaneously solved problems leads to a limited capability to divide movements by frequencies for modelling in the OCP and solving smart grid problems.

**Separation of movements by meaning:** Further solution of the problems leads to using the method of separation of movements by meaning [9–11]. We will understand the separation of the dynamic flow of information into hierarchically subordinate structural elementary parts and the operation of these parts (**Figures 10**–**12**). Additionally, the division into alternative information flows 'For-Against' is performed.

**The relationship of the methods of separation of movements:** The separation of motions in frequencies determines the structure of oscillatory motions in the OCP (**Figure 7**), but the meaning of these motions is determined by the division in meaning (**Figure 10**). To clarify the relationship of the methods, an analogy can be introduced. The method for separating movements by frequencies describes the relationship of all the available circuit elements. This description is located within a single plane. At the same time, the LFC processes take up the resources of the computing system while the HFC processes are being calculated. The method of separation of movements by meaning represents the relationship of the elements in the circuit, not in the plane but in space [11–13].

Within the framework of the SI method, we can talk about the method of separating movements by frequencies as an additional preliminary hierarchical level of the method of separating movements by meaning. The application of the above methods can be as follows—structural-operator, identification, separation of movements by frequencies to describe the OCP and then the SI method with structural-morphological, structural-syntactic and structural-semantic steps.

### **9. Structuring OCP semantic** *SN* **situations**

The parameters of the electrical signals are only the *SN* carriers. The characteristic features of the input coordinates of the RPA are the natural spatio-temporal sequence of consideration of the information components. The SI method is applied to the description of the OCP. All *SN* components are located in a certain way relative to each other and relative to the general synchronising time axis [10, 11]. The

#### *Automatic Control of the Structure of Dynamic Objects in High-Voltage Power Smart-Grid DOI: http://dx.doi.org/10.5772/intechopen.91664*

semantic information about the state of the OCP can be represented in the form of separate elementary *SN* situations. Each *SN* characterises the corresponding known (classical) state of the OCP. The problem arises of separation of the information set of states and recognition of the *SN*. In the limit, *SOCP(t)* can be specified by a single *SN*. This becomes the minimum information for building an OCP model, which reduces the time required for a single calculation in CAD.

The OCP scheme can be in dynamic consideration in one of the semantic situations of *SN*. Suppose that *S1* 'NM' corresponds to the steady-state values of the OCP internal parameters (operator outputs, NTS symbols, *P* rules). Thus, the concept of semantic situation *SN* means the appearance of the reaction Δ*UOUT* of the OCP structural scheme in response to a change in Δ in any OCP coordinate. We also understand the structural, logical relationship of the individual TS control points in the structuraloperator model of the OCP or equipment that form the transient signals (**Figure 9**). And also *SN* means a part of the OCP formation tree with activated root symbols *PS*, *PB*, then NTS and TS. The steady state of the OCP parameters can be distinguished and named *SN*. By the *SN* situation template is meant the sequence of characters *PS*, *PB*, TS, NTS of the OCP tree established for this *SN*, which is formally described by the GOCP grammar. Thus, it is necessary to systematise all *SN* situations. These *SN* definitions are based on the OCP. The definition of *SN* relative to RPA devices is introduced as an analogy—each *SN* corresponds to a stencil with the corresponding sequence of 'selectivity windows'. Compilation of the OCP generation tree can be planned using the table transfer function *WTABL* = TSN/*SN* [9, 11]. *WTABL* is populated based on emergency files as well as by calculating OCP models and GESRPA schemes in CAD.

The *SN* tree consists of a series of *SN*, replacing one another in time logically sequentially as the transition process develops (**Figure 12**). A scenario of *SN* development is formed.

A special role in the operation of the OCP is the situation of *SN* 'NM'. Although this *SN* does not apply to single-phase insulation faults to ground (OPG), it is from this that it begins, and it ends with its analysis of the transient into semantic and structural-informational components (**Figure 13**). The normal *SN* mode includes: (a) *SN* 'NM' itself; (b) *SN* 'processes not related to OPG'; and (c) *SN* 'neutral displacement', caused by the exceeding the normalised levels of emergency situations and resulting from the operation of the technological equipment of the distribution network.

Characteristic *SN* situations can be highlighted (**Figure 12**). The initial OPG breakdown (the first damage to the network insulation until a pronounced neutral reaction of the network), then the network reaction to the initial breakdown, subsequent OPG breakdowns and the restoration of *SN* 'NM' after OPG elimination are different stages of the transition process, of which OPG is a particular case. Of these named elementary *SNs*, the 'GESOCP by *SN* situation' formation tree is composed. Recognition algorithm in RPA devices restores exactly such *SNs*, *SN* scripts and *SN*

**Figure 13.** *Structural schemes of GESSN semantic situation* SN *in OCP by signal* S(t)*.*

script tree. Therefore, the description of the OCP obtained by the SI method should return all possible relationships in *SN* in the *SN* tree.

In the dynamics, a sequential change of the elementary *SN* occurs. As a result, a scenario for the development of the *SN* appears. The OCP can be in one *SN* state for a long time (e.g. *SN* 'NM', *SN* 'metallic OPG', *SN* 'skew'), for a short time (*SN* 'metallic') or very briefly (*SN* 'first half-wave OPG'). Scenarios of *SN* development can also be sequentially described by the logical change of certain elementary *SNs*. Such scenarios are typical for OCP and should have their own names (e.g. *SN* 'intermittent arc', *SN* 'self-eliminating multiple breakdowns'). In RPA algorithms, such *SN* scenarios are restored at a semantic level of recognition. It is possible to create an *SN* transition tree (**Figure 12**). Both mutually inverse formation and recognition trees make up the 'GESOCP scheme for the *SN* situation'. We can distinguish 'GESOCP along oscillatory circuits' schemes for considering the separation of movement and a 'GESOCP scheme for *SN* semantic situations', which shows movement in the meaning of *SN* situations.

Thus, the recognition algorithm determines not only the *SN* situation but also the essence of the transition process in the OCP. At this recognition level, a significant part of the non-selective operation of RPA devices occurs due to the limited or lack of appropriate *PN* rules in RPA algorithms.

The task associated with RPA and OCP management has the peculiarity of intersecting *SN* semantic situations. Generally speaking, in order to increase the stability of the operation of RPA algorithms for each area of overlapping situations *SN*, it is desirable to define its own information sensor TS. The more it is necessary to determine the current *SN*, the greater the number of TS that should be laid in the structure of the algorithms. Reducing this intersection is the ultimate goal of a theoretical description of the OCP. For this, according to the theory of information, it is necessary to supply an excessive amount of information for rechecking, determining errors and recovering information from errors for a recognition system. In practice, the implementation of this important property does not occur. This leads to recognition errors.

In a real OCP, there are third-party processes unrelated to typical *SN* situations and *SN* scenarios. These may be present for a long time and be registered by some TS in the RPA. They need to be discovered and their named list compiled. Formation can be in CAD based on mathematical functional modelling, with real emergency files. In the presence of a generated mathematical model of the OCP or individual equipment, it is possible to introduce situational changes from the signal source at a certain moment during the transition process, which interfere with *SN* 'NM', for example, by shortcircuiting or shunting a single element, or a series of elements in the structural-operator model of OCP, or equipment (**Figure 8**). This leads to observable transients. Similarly, it is possible to repair the cause of damage through transient signals in real emergency files.
