Designing an automated control system for changing NPU energy release compensating for arising internal disturbing factors based on their approximation model

Abstract

The necessity of keeping in working condition the sources of traditional electricity generation for dispatching the supply of electricity from the capacities of "green" electricity generation has been realized. Potentially, one of these sources may be nuclear power plants. An obstacle to their use as a participant in dispatching is the impossibility of maneuvering with power in a wide range. One of the reasons for limiting the range is the complexity of automatic compensation for the reactivity of the xenon oscillation reactor. Existing physical and mathematical models for calculating the parameters of processes in the reactor due to changes in its power because of its complexity cannot be used in operational automatic control systems. The task of constructing an approximation linear model of processes in the reactor in the form of a transfer function is set. To build an approximation model, the inverse problem is solved. The desired model is based on the condition of coincidence at some time interval of the results of solving it with the results of a detailed physical-mathematical model. To this end, a number of sequential actions are performed, including approximation of the results of the expanded physical-mathematical model using a series, the application of the Laplace transformation to this series, as well as Pade approximation obtained in the space of the images of the series. The method of control was proposed and an automatic control system (ACS) for energy production of nuclear power plant has been synthesized. To this end, the management system was integrated with the approximation model of the active zone, which provided the possibility for adjusting the quantitative degree of stability of the active zone. ACS consists of three control circuits. Such a structure has made it possible to compensate for the xenon oscillations that occur. Additionally, ACS reduces the movement of adjusting rods in the active zone, which reduces local power surges in nuclear fuel and leads to an increase in its durability

A method for searching the best static program for nuclear power unit control in the event of perturbations of different nature

“…With the help of these automatic control systems, three static control programs were studied for the same objecta nuclear power unit with a pressurized water reactor [21]. To study transient processes during the transition from one control program to another, a switch of these programs was added to the existing model of an automatic control system [22,23].…”

Structure of a Multi-Zone Model of a Pressurized Water Reactor

“…Figure 1 shows a simplified diagram of the structure of the distributed model of the reactor core. Each zone structurally includes a point model of reactor kinetics that relates the neutron flux density to reactivity, a model of energy release in the fissile material that determines the amount of energy released as a result of fuel fission reactions depending on the neutron flux density, a coolant heating model, a model of heat transfer inside fuel rods that relates fuel temperature with the amount of energy released, a model of the reactivity effect from xenon poisoning, a model of the temperature effect of reactivity, a model of the power effect of reactivity , a model of the reactivity effect of the control group of reactor control and protection system, and a model of the reactivity effect of boron regulation [3,4]. The multi-zone structure of the reactor model divides the reactor core in order to reduce the modeling error resulting from the linearization of a nonlinear object and enable implementation in a simulation environment [5].…”

Automated Control of the Heat Supply System With a Variable Structure According to the Value of the Objective Function of the Optimization Problem

“…У сучасному суспільстві, з підвищенням якості життя зростає рівень вимог до функціональних характеристик різних комп'ютерно-інтегрованих систем керування (КІСК). Від сучасних КІСК потрібна надійна адаптація до зміни середовища їх використання з відсутністю або мінімізацією втручання оператора під час функціонування [1]. Сучасний рівень розвитку теорії оптимального керування (ОК), теорії адаптивних систем і також рівень досконалості КІСК дозволяють розв'язати нове завдання керування, технічними структурами не тільки за параметрами, а й за структурною множиною одиниць взаємозамінного обладнання, що відрізняється за своєю надійністю, ефективністю і вартістю.…”