Handbook of Electrical Engineering

428 HANDBOOK OF ELECTRICAL ENGINEERING

Figure 15.12 Instantaneous voltages and currents in an induction motor supplied from a voltage source inverter.

Table 15.5. Peak values of har-

monic current components

Harmonic

number

Peak value and sign

of the component

current

1 +554.74

5 −110.95

7 −79.25

11 +50.43

13 +42.67

17 −32.63

19 −29.20

From the Worked Example 15.4.3.1 the combined impedance of the rotor and magnetising
branches isZm 2 = 0. 00348 +j 0 .5362 ohms. Adding the stator impedance gives,

Z 1 m 2 = 0. 00878 +j 0 .7711 ohms

All the harmonics of the supply current have either zero or 180◦phase shift as seen in Table 15.5.
The fifth harmonic supply currentI 15 is− 110. 95 /

√

2 amps (rms). Inject this current into the circuit.