Centralized normalization of voltage harmonics in the network with distributed nonlinear load by the third-order filters

The paper studies the problems on centralized normalization of harmonic voltages in the network with distributed nonlinear loads by the passive third-order filters. The nonlinear loads are connected to the extended HV network at practically equal distances. Each nonlinear load is of sufficiently high power and causes sizable distortions in the supply network. The harmonic voltage values at the nodes of nonlinear loads connection to the supply network exceed the limits established by the standard. The paper addresses the problems of choosing the passive third-order filters: choice of the node for filter installation, calculation of filter parameters, evaluation of the efficiency of chosen filters for centralized normalization of harmonic voltages at the network nodes. An example of choosing filters for the real 220 kV network supplying power to traction loads is given.