Modelling of distributed generation for radial power flow algorithm

The models for distributed generations which can be used in radial load flow program is proposed in this paper. In most cases, distributed generations like photovoltaic systems, fuel cells, low capacity wind turbines and diesel gensets etc. have their terminal voltage not equal to the slack bus voltage. This paper addresses such distributed generations. In this method, an improved backward forward sweep algorithm is employed where the line flows are used to form a quadratic expression which can be solved directly. For handling voltage controlled buses, the Q injection required for maintaining the specified voltage is calculated using the solution of quadratic equation. Though this method uses the backward forward strategy, the overall convergence is achieved similar to Newton´s method. The algorithm proposed in this paper has been implemented on two radial systems and its results are compared with Newton´s method.