Fast decoupled load flow(FDLF)algorithm has been widely used in the domestic and international power dispatch and control center and planning department. The FDLF algorithm usually has very high computational efficiency. But for the transmission networks and distribution networks with high resistance-to-reactance ratios

the mathematical basis of the FDLF algorithm is no longer satisfied

and its convergence and computational efficiency are poor. So the FDLF algorithm cannot be applied to the transmission networks and distribution networks with high resistance-to-reactance ratios. The above problem is addressed by transforming active/reactive power at buses so that they can be classified as quasi active/reactive power at buses

which have better decoupling characteristics. And this decoupling property is independent of the value of resistance-to-reactance ratio. On this basis

a generalized fast decoupled load flow(GFDLF)algorithm is proposed. The GFDLF algorithm is based on only one assumption

rather than three assumptions used in the conventional FDLF algorithm. As a result

the GFDLF algorithm has good adaptability to both power transmission network and distribution network(including the network with high resistance-to-reactance ratio). Simulation results show the effectiveness and efficiency of the proposed method.