**2. Separation of dynamic objects with variable structure into a separate class**

Dynamic OCP management and control objects are those in which their internal information state develops sequentially in time, a new state replacing the previous one. We will call the elementary state the semantic situation *SN*, for example, *S1* 'normal operation' or 'NM'. One *SN* gives rise to another or many possible known developments. Such transitions to a fixed *SN* are similar to the operation of automaton models. A sequential change in time of the parameters, structure, dynamic properties and individual elements of the OCP is possible. The removal of sections from the OCP structure for various reasons or combining them into a common structure during the operation of automatic control devices is typical.

The OCP is characterised primarily by a change in time of the internal structure. Parametric changes are the result of such a change. For example, the task of adjusting the coordinate parameter *L* to changing the coordinate parameter *C* is successfully solved (**Figure 3**). Changes in parameter *C* result in changes of different types—(A) a change in the structure of the OCP by disconnecting the *QN* switches of the separated sections of the OCP; (B) there is a test change of the parameter *L* during operational work in the 'NM' mode, while the structure of the OCP does not change; and (C) the damaged section is disconnected by the *QN* switch by selective relay protection. In some modes of structural change, when damage occurs, blocking changes in the parametric coordinate *L*.

An analysis is made of the methods for describing well-known typical schemes of RPA systems to justify the possibility of operating with such a concept. So, on well-known typical schemes, a single-line OCP scheme, EU executive bodies,

**Figure 3.** *Structural scheme OCP (LZSC) with a Petersen's coil* L*.*

measuring transformers and the measuring part of the relay are indicated (**Figure 3**). The relay output was initially replaced with a multiple control result from immediate shutdown to alarm.

In RPA tasks, the perturbation control principle is common. It is known that this principle is characterised by the presence of fatal errors and is relevant in the event of catastrophic failures in the OCP equipment. But most of the insulation damage to the network (75–98%), according to well-known statistics, can self-destruct. To do this, RPA algorithms must steadily determine such a transition process. Case studies have found that, in such *SN* situations, robustness of the RPA systems was not achieved.
