Construction engineering organization of Golestan province ,Iran
Filtering the harmonics produced by nonlinear loads in power systems is an important issue for the engineers to follow. In most cases, to this end, active filters have been used. In this paper, however, it is shown that this task can be accomplished using a Multi-Criteria algorithm and distributed generations (DGs) resources. In the proposed algorithm, when the DGs are connected to the main network, compensations of active and reactive powers as well as harmonic components are possible. To do so, first, the dynamical model of the systems will be shown in details in the static three-phase system, and then, they are transferred to a rotating orthogonal set using the necessary conversion equations. Therefore, the transferred variables are used to control the voltage source converters in order to achieve improvements in DGs’ behavior when they are connected to the network. In this control method, the active and reactive powers transmitted to the load as well as the current harmonics are compensated using samples of voltages and currents taken at the connection points; thus capabilities for sinusoidal current and maximum active power transmissions are provided. Besides, the control proposed method has a fast dynamical response in active and reactive power compensations. Therefore, using this control approach, the transmitted power of DGs to the network are maximized, the power coefficient factor is improved and current harmonics of the load are decreased significantly.