Efficiency determination of converter-fed induction motors: Waiting for the IEC 60034–2–3 standard

European standard concerning the determination of the rated efficiency of converter-fed induction motors is not yet available if not as a draft version. Waiting for the approved standard IEC 60034-2-3, in the paper the draft version is analyzed, together the possibility to use IEC 600034-2-1 Standard, valid for sinusoidal supply, with PWM inverter supply too. At this purpose, the authors carefully defined the concept of additional harmonic losses introduced by the inverter voltage waveform and tested four Total Enclosed Fan Cooled (TEFC) induction motors. The obtained results have put in evidence the potential applicability of IEC 600034-2-1 for the determination of the efficiency of inverter fed induction motors. The reported results and discussions could be useful for the Standard Commission members working on the definition of tests and procedures to solve this problem.