Electrotechnical Systems

222 Electrotechnical Systems

(Br3isgetting open). At t = 1.4 s the gate pulses are sent to the inverter switches, and

at t = 2 s the speed reference is switched on that is equal to 0.95 of the rated value. IM

is speeding up with the rated load torque of 0.5. At t = 7 s the load torque rises to the

rated value. In Figure 5.56 the IM speed, its torque, and the current are shown, and in

Figure 5.57 and Figure 5.58 the capacitor voltages and the IM stator voltage and the

0

0

0.5

1

1234

Speed

56

78

0

0.5

1

Torque

01234567 8

0

–2

2

I

motor

t (s)

01234567 8

FIGURE 5.56 Processes in the electrical drive with the «ying» capacitors.

0

2000

–2000

01234

t (s)

U

load

(V)

56

78

01 ...