Definition of Fact and Place of Losses in Low Voltage Electric Networks

The paper presents a complete research of nontechnical losses detection methods and gives a method to define the fact, place and volume of energy losses in low and medium voltage electric networks. The method based on the capabilities of modern counting electricity devices in conjunction with the automatic system for commercial accounting of power consumption. In addition, the article describes a device, which can be used for same things in networks that are not equipped with modern counting devices. The fact of unaccounted consumption can be determined using information about the current's balance in network. If unaccounted consumption is confirmed, the method gives a way to calculate a volume of unaccounted consumption and its place in network. The method is based in general on the Ohm's law: in the electrical circuit all currents cause a voltage drop on a load, and on a resistance of power wires too. Therefore, the voltage drop that should be on a fragment of the network under review can be counted using data from electricity counting devices. If the calculated volt drop does not match to the actual one, the conclusion about unaccounted consumption on this fragment of the network is made. Using information about physical parameters of power wires; calculated current's imbalance and difference between actual and estimated value of voltage drop, places of unaccounted consumption in network can be found as well as values of currents, flowing through them. The obtained errors of received values are comparable to errors of counting devices used in the network. So, the values obtained using this method can be considered quite reliable.