Mathematical modeling of the regular-mode electric power supply and electric power consumption processes of the organization

The article deals with the problem of simulation modeling of rectifiers control system for the modular uninterruptible DC power supply unit in order to increase energy efficiency of its operation. This paper proposes a control logic algorithm to manage the process of switching the power modules of the UPS in the adaptive correction mode of the system nominal power. The main idea of the method is to implement the process of turning on/off the rectifiers to achieve the optimal value of their load factor and maintain its level in a certain set optimal range. Control system block diagram of the modular uninterruptible power supply is provided. Besides the central control module rectifiers, control units are introduced. They are responsible for realization of their on/off switching process and carries out control of their condition. In order to study the effectiveness of the developed algorithm, a computer model is created to describe the control logic of rectifiers management. To implement the simulation model, the software environment for visual modeling Simulink Matlab and the mathematical apparatus of the Stateflow component library are used. The developed simulation model has been tested and the simulation results are given in the research. The application of the developed algorithm allowed to increase the efficiency of the uninterruptible power supply by adjusting the load factor of the UPS in real time within a predetermined optimal range of values. The simulation results demonstrate the effectiveness of the developed simulation model of the control system in different operating modes.

Control system simulation by modular uninterruptible power supply unit with adaptive regulation function

Palamar¹

2020

Development of resource-saving and environmentally safe beryllium bronze soldering technology

Berezhnyy¹,

Капустян²,

Kulykovskyi³

et al. 2020

The composition of the solder, which provides the necessary technological properties of the product, namely, electrical conductivity and mechanical strength of the junction was selected. The possibility of brazing beryllium bronze with a silver contact plate by furnace brazing using fluxes based on NaCl: CaCl2: CaF2 salts, respectively (24: 61: 15% mass) in the atmosphere was established. The possibility of brazing BrB2 beryllium bronze in the atmosphere using a research flux based on the eutectic of the NaCl – CaCl2 system (28…72% wt.) adding 15% CaF2 over a copper layer is shown. The technology for brazing beryllium bronze BrB2 with silver contact plates with silver solder PSr68 has been developed. The brazing process is combined with the hardening operation, which allows avoiding additional thermal operations; flux residues are removed during hardening and do not actually need additional cleaning operations; applied solder, flux components and technologies for applying a layer of copper are not scarce and relatively cheap, which can significantly reduce the cost of the product, subject to the requirements of the technical specifications. A technological process that makes it possible to refuse of using vacuum systems and toxic fluxes has been developed.

Determination of the characteristic function of discrete-time conditional linear random process and its application

Fryz¹,

Mlynko²

2023

The discrete-time conditional linear random process is defined, and its properties in the context of application for mathematical modelling of information signals in energy and medicine are analyzed. The relation to the continuous-time counterpart is considered on the basis of time sampling and aggregation. One-dimensional and multidimensional characteristic functions of discrete-time conditional linear random process are obtained using conditional characteristic function approach. The conditions for the investigated model to be strict sense stationary are justified.