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The high performance characteristics of Peltier thermoelectric modules (TEM) in comparison with compressor cooling systems are determined by the convenience of their use for both cooling and heating, technological advantages due to the absence of moving parts, etc. To effectively regulate the temperature conditions of TEM, it is necessary to develop automatic control systems with specified characteristics. Modeling and design of such systems is complicated by the essentially nonlinear properties of the constituent units, as well as the control object - the Peltier module. To analyze the nonlinear stability of a trigenerative climate control system based on TEM, a mathematical model of the system in the form of transfer characteristics based on approximation by piecewise linear functions has been developed. The relations defining the conditions of absolute stability of the model in the nonlinear mode according to the Popov criterion are obtained. As a result of the simulation, the stability areas of the system are calculated with varying parameters of the component links. The directions for the further use of the proposed methodology for the subsequent optimization and synthesis of TEM control systems are determined. [ABSTRACT FROM AUTHOR]

Modern unmanned aerial vehicles (UAVs) are used to perform a wide range of flight tasks (military and civil), implemented both in autonomous flight mode and by remote control. One of the advanced technologies for their use is the organization of flying sensor networks (FSN). The quality of information exchange in FSN, widely used for monitoring of various natural and technical objects, depends significantly on the conditions of signal propagation and the level of external interference. A promising method for improving FSN performance is to adapt the transmission mode depending on the signal-to-noise ratio at the input of UAV receivers, namely, changing the encoding speed and modulation method. To adapt the physical level of the flying sensor network, it is proposed to use a hybrid method of network management based on artificial neural networks (ANN) and fuzzy logic. For practical implementation of the proposed approach, a functional scheme of a closed automatic control system with negative feedback for the receiving and transmitting module of UAV radio transmitters is proposed. The scheme is based on a fuzzy controller with an auto-tuning unit based on an artificial neural network with a single hidden layer. This functional scheme of the automatic control system of the physical layer of the OSI network model for the receiving and transmitting module of UAV radio transmitters can be built on the basis of all possible known variants of controllers (proportional P, integral I, proportionalintegral PI, differential D, PID, etc.). The fuzzy controller is synthesized using the Takagi-Sugeno fuzzy inference algorithm. [ABSTRACT FROM AUTHOR]