Digital Twin Aggregated into a High-Efficiency Charge-Discharge Device of the Power Supply System of a Spacecraft

The power supply system (PSS) of a spacecraft (SC) is one of its most critical systems. The generation of electrical energy in modern SC PSS is typically carried out by solar panels (SP). In the absence of energy generation from the SP or during periods of low energy output, the necessary electrical energy is supplied to the load from battery packs (BP) through a charge-discharge device (CDD). Usually, the CDD is connected in parallel to the output buses of the PSS and, in battery discharge mode, provides stable voltage to the load. The replenishment of energy in the BP — its charging — occurs during time inter-vals when the energy generated by the SP exceeds the energy consumed by the load. Additionally, the CDD can provide voltage stabilization at the load. The article presents the power circuit of a pulse converter capable of reversing the flow of energy and operating in a buck-boost mode with high efficiency. It is shown that using the power circuit of this pulse converter in the CDD of SC power supply systems can improve several of their characteristics, namely, energy-mass and reliability metrics, enhance efficiency, and improve the quality of the output voltage of the PSS while reducing the level of generated electromagnetic interference. The article includes research results on the CDD, with the power section designed according to a prom-ising scheme obtained using a simulation model and a physical prototype. It is demonstrated that the synthesized control law allows for maintaining the astatism of the output voltage and a short duration of tran-sient processes. However, it was found that the simulation model of the CDD provides a shorter duration of transient processes compared to the physical prototype. This is explained by the fact that due to the short time interval during which the controlling microcontroller must perform calculations for switching mo-ments of the power transistors, the mathematical expressions used for calculations had to be simplified. The aim of the work is to find a technical solution for generating control signals that allows for the elimination of complex mathematical calculations of the switching moments of the power transistors in realtime. To achieve this, it is proposed to precalculate the switching moments of the power transistors for the entire range of power transmitted through the CDD and for the entire range of possible voltages on the BP. The obtained values of the switching moments of the power transistors in the form of tables should be recorded in the memory of the microcontroller controlling the power circuit of the CDD and used for control purposes. The article discusses the methodology for obtaining tables of switching moments for the power transis-tors of the CDD, which essentially serve as a digital twin of the CDD, and provides an example of such tables.