3.5 Shunt Elements

A shunt connected element such as a capacitor or inductor is modeled as a fixed impedance to ground at a bus. The admittance of the shunt element at bus i  is given as

yish = gish + jbish

and Y  =  G   + jB
 sh    sh      sh  denotes the n  × 1
 b  vector of shunt admittances at all buses. The parameters  i
gsh  and  i
bsh  are specified in columns GS (5) and BS (6), respectively, of row i  of the bus matrix as equivalent MW (consumed) and MVAr (injected) at a nominal voltage magnitude of 1.0 p.u and angle of zero.

A shunt element can also be used to model a constant impedance load and, though correctly, Matpower does not currently report these quantities as “load”.