Load flow calculation with voltage regulators bidirectional mode and distributed generation

This letter presents a problem of calculating load flow in distribution feeders via the conventional three-phase backward/forward sweep method when voltage regulators in the bidirectional mode are experiencing reverse flow due to power injection from distributed generation downstream the regulators. It also presents a simple but effectively modification in the algorithm of that method to overcome the problem. A modified version of the IEEE 34 buses distribution test feeder will be used to demonstrate the problem and the proposed algorithm solution.