2 research outputs found
STEROWANIE ORAZ SYNCHRONIZACJA DWUPOZIOMOWEGO FALOWNIKA NAPI臉CIA W WARUNKACH PRZEJ艢CIOWEJ ASYMETRII NAPI臉膯 SIECI
This paper presents the operation of grid tied, two level voltage source inverter (VSI) during network voltage unbalance. The control system was implemented in synchronous rotating reference frame dq0 (SRF). Two types of control structures were investigated herein. First utilizes the Double Decoupled SRF Phase-locked loop (DDSRF-PLL) synchronisation with positive and negative sequence currents control. Second one is simplified system that does not provide symmetrical components decomposition and decoupling for synchronisation. Simulation results exhibited a superior performance of the DDSRF-PLL control system under grid voltage unbalance.Niniejszy artyku艂 przedstawia prac臋 dwupoziomowego falownika napi臋cia wsp贸艂pracuj膮cego z sieci膮, podczas przej艣ciowej asymetrii napi臋膰. System sterowania zosta艂 zaimplementowany w wiruj膮cym uk艂adzie synchronicznym dq0. Przeanalizowano dwa typy sterowania. W pierwszym zastosowano metod臋 synchronizacji z odprz臋ganiem DDSRF-PLL wraz z mo偶liwo艣ci膮 kontroli pr膮d贸w sk艂adowej zgodnej i przeciwnej. Drugi natomiast w swoje uproszczeni formie nie pozwala艂a na sterowanie obu sk艂adowych symetrycznych, zabrak艂o r贸wnie偶 odprz臋gania podczas synchronizacji z sieci膮. Wyniki symulacji pokaza艂y o wiele lepsze dzia艂anie pierwszej metody sterowania
Influence of Renewable Energy based Microgrid on Low Frequency Oscillation of Power Systems
Increase proliferation of microgrid (MG) technologies
with extended use of renewable energy sources (RES) can affect
the system stability performance since dynamic characteristics of
this kind of MG are different from conventional generation.
Sharing certain portion of or entire generated power from
synchronous generator with MG results in decrease of total
system inertia. On the other hand, connecting RES based MG
near a central load eventually enhance system performance due
to improvement in reliability, reduction of power loss and
congestion on transmission line. This paper investigates the
impact of RES based MG on local and inter-area oscillatory
modes of power systems. This study focuses on low oscillatory
eigenvalues in the frequency range of 0.1-2 Hz. Eigenvalues
analysis is performed to observe damping ratios and stability
margins of the system due to MG integration. Furthermore, time
domain simulation is then carried out to validate the result from
eigenvalues analysis