This work summarizes efficiency measurement results of a full bridge, 3 phase inverter composed of state-of-the-art Si IGBT transistors and Si or SiC diodes. Different (symmetrical and discontinuous) space vector modulation strategies were chosen in order to examine their influence (together with modulation frequency) on inverter losses. Induction machine was used as load, different load points were examined. Results clearly show, that proper modulation strategy, minimizing the switching losses of semiconductor switches, can increase the overall output efficiency at about 1% in case of both silicon and hybrid constructions. The drawback of DPWM approach is connected with the decreased quality of inverter output current. Hybrid technology can also improve the output efficiency at about 1% when compared to traditional constructions, but only in case of elevated switching frequencies. At low frequencies (below 10 kHz) modern semiconductor offer comparable results at much lower device costs.
The paper presents the results of research work on the development of a rapidprototyping test stand for testing: servo control algorithms, trajectory generation, algorithms for increasing overall quality of the feed-drive modules within two axis (X-Y) table of the milling machine. Open architecture interface of the prepared control system lets the potential user test functionality of integration of diagnostic tools within the motion controller - directly, without taking into account communication with top-level CNC system.
The paper presents selected simulation and experimental results of a hybrid ECPMS-machine (Electric Controlled Permanent Magnet Synchronous Machine). This permanent magnets (PMs) excited machine offers an extended magnetic field control capability which makes it suitable for battery electric vehicle (BEV) drives. Rotor, stator and the additional direct current control coil of the machine are analyzed in detail. The control system and strategy, the diagram of power supply system and an equivalent circuit model of the ECPMS-machine are presented. Influence of the additional excitation on the performance parameters of the machine, such as: torque, efficiency, speed limits and back-EMF have also been discussed.