Rudnicki, Tomasz, Andrzej Sikora, Robert Czerwinski, and Dariusz Polok. 2016. “Impact of PWM Control Frequency onto Efficiency of a 1 KW Permanent Magnet Synchronous Motor”. Elektronika Ir Elektrotechnika 22 (6):10 - 16. https://doi.org/10.5755/j01.eie.22.6.17216.