Persons

During development of the secondary power supplies the most important components are increased efficiency and reduced weight and size parameters. In the paper the power transistor switching algorithms intended for use in the power supplies, equipped with a digital control system, has been proposed. The work of the algorithms is based on the determination of time points in the process of energy conversion, at which the transistor occurs with the minimal energy loss. Unlike the existing algorithms, being considered, several such algorithms have been determined, and further work of the proposed algorithms consists in forming a sequence of control pulses. It has been shown that this sequence permits to switch the transistor at defined moments with different time intervals, is quasi-resonant in nature. The presented algorithms carry out the correction of the output parameters of the power source through the use of PFM and correction of the generated sequence of control pulses. The application of the presented algorithms permits to reduce the controller load level by the operations of communication with the analog-to-digital converter up to 40% and not less than 2 times to reduce the level of electromagnetic interferences compared to the existing algorithms. Their most important advantage is modernized quasi-resonance approach in determining the switching moments of the power switches, which allows maintaining the minimal level of energy lost on switching, increasing the efficiency of the power source and reducing the size of the heat removal system.

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In development of energy converter for feeding the phase rotators and modulators in the system of active phased antenna lattice special requirements to sizes with the specified nominal and peak power of the converter have been presented. In the paper, the concept of manufacturing DC/DC energy converter with reduced weight and size parameters has been presented. It has been proposed to use the switching boards based on aluminitride ceramic with a thermal conductivity of 180-200 W / (m·K). To further reduce the energy losses due to overheating of the components, a digital control system for switching the power switches has been used. A significant reduction in height corresponds to the replacement of a coil transformer with a planar one. The following results can be achieved: an increase of specific power from 2.18 to 3.23 kW / dm; an increase of peak specific power from 5.66 to 8.4 kW / dm; a reduction of the height of the experimental sample from 32 to 13 mm; a decrease of volume from 0.115 to 0.0773; an increase of efficiency from 85 to 88.6%.

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