SURFACE POWER LOSSES IN THE CORE OF INDUCTION MOTORS SUPPLIED BY A PWM VOLTAGE INVERTER

The calculation of additional power loss components in an induction motor supplied from a PWM inverter has been carried out with the assumption of constant load torque, the frequency of fundamental harmonic being adjusted in the range of 20 to 70Hz. The tests presented refer to a squirrel‐cage induction motor Sf 132 M4: PN = 7.5kW, UN = 380V (&Dgr),ƒN = 50Hz, 2p = 4.