
27-16 Power Electronics and Motor Drives
consists of two inertial elements from which only one can be directly controlled. e remaining element
is usually stable if all controlled variables are stabilized and do not require additional control or correction.
One controller is sucient for this structure as presented in Figure 27.4.
e control variables acting in the subsystems have to be limited because of limited power of the
supplying inverters. ere are two ways of limiting the control variables. e simple way is the limi-
tation of controller outputs on constant levels resulting from inverter voltages in steady states and
margin resulting ...