4. Starting and speed control at constant frequency and voltage

4.1 Reduced voltage starting

Figure 14 a shows the usual admittance diagram for a motor of the industrial type: the center C and very close to the reactive power axis, the points P ₁ and P _× are very close both to each other and to this axis. The point P _n , corresponding to the nominal slip g _n , is located in the left-hand part of the circle so that O P _n...