DC-DC converters are widely used in hybrid power supply systems. A buffer source of electrical energy (most often a battery bank) and its charging and discharging devices are integral parts of such systems. In systems where the battery bank voltage is less than the DC-bus voltage and galvanic isolation is not required, the Weinberg converter is widely used as a discharge device, for example, in spacecraft power supply systems. The current trend in the development of hybrid power supply systems is to increase the power density of the system. Increasing the operating frequency is the simplest and most effective way to increase the power density of converter. A differential characteristic of this converter is the zero-current switching (ZCS) of transistors, which occurs due to the influence of the leakage inductance of coupled-inductors and the leakage inductance of the transformer. The paper presents an analysis of the influence of leakage inductances on the operation of the converter and a method of determining a level of turn on switching losses of transistors, which allows to ensure the necessary level of efficiency of the converter. The results of simulation modeling of the converter confirm the effectiveness of this method.