A battery DC power source for a small oscilloscope was designed and constructed. Its output voltage is ca. 300 V and its output power is about 60 W. A series-resonant DC/DC converter with a pulse transformer is the core of this device. The source is supplied from a Li-ion battery with nominal voltage of ca 3.6 V (several cells connected in parallel). It is often necessary in power electronics measurements to have a galvanically separated supplying of the oscilloscope. A mains power supply with low parasitic capacitance is sometimes used but for some special measurements even this small capacitance (e.g., 50 pF) is too high. The battery supplied power source can achieve a lower capacitance. Certainly the possibility to use the oscilloscope without available mains power is advantageous.

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This paper discusses two loss minimization algorithms for induction motor drives. Firstly, equivalent models in the form of Gamma and inverse Gamma are shown, from which the loss models were obtained. Then, the procedure for determining the two algorithms is presented. The results show that it is easier to determine the loss minimization algorithm for rotor flux. In terms of accuracy, both algorithms are similarly accurate.

The paper deals with design of independent battery powered drive for wheelbarrow and gives basic overview and comparison of various conceptions of battery powered wheelbarrow drive.

This paper discusses a simulation of a loss minimization algorithm for induction motor drive. This algorithm, which is based on motor parameters, varies the flux linkage to obtain the lowest possible losses. Verification of the algorithm's functionality was performed by simulations in MATLAB/SIMULINK environment. First, an induction machine model was built with the parameters of a real motor, taking into account magnetic saturation, Joule losses in both windings, iron losses, and mechanical losses. Then, simulations with indirect field-oriented control were performed. The simulations showed that there is an increase in efficiency in the low torque region.