A three bus system having a regulating transformer(RT) in the line 1-2 near bus 1 is shown in figure,the complex ratio of RT IS ‘a’.The per unit(PU) in the line admittances are indicated in the figure.The lines resistance and shunt admittances are negligible.Determine the Y bus matrix for ‘a’ =1.05<-2°, and changes in real power flow p12 and reactive power flow Q12 when ‘changes from 1.0<0° to 1.0<-3° 1. Compare and contrast between Newton-Raphson,decoupled load flow and fast decoupled load flow method of load flow analysis. 2. Describe the algorithm for solving aload flow problem using the Newton-Raphson method