Impacto do controle de potência reativa e tensão na detecção de ilhamento em gerações distribuídas

Abstract

The growing use of distributed generation create challenges to overcome in distribution networks. Among these problems are unintentional islanding and voltage profile change by the insertion of distributed generators. Islanding poses risks to the maintenance worker’s integrity, can cause damage to distribution network equipment, and decreases the quality of electrical energy supplied. On the other hand, changing the voltage profile can lead to the extrapolation of adequate voltage limits and violation of voltage level compliance indicators. Among the strategies used to avoid problems with voltage limit violation, we highlight the reactive power control methods. The use of reactive power control by distributed generators avoids re-conducting in the distribution network and the transformer TAPs in the system. In this sense, the work aims to analyze the performance of islanding detection methods in generators that control the voltage at their terminals. It seeks to evaluate the change in the control mode of distributed generations impacts the islanding’s detection. For this, it simulated island situations, short circuits, capacitor bank coupling, and load opening. In the simulations, two plants were modeled: one with a photovoltaic inverter and another with a synchronous generator. The simulations were carried out in MATLAB/Simulink, using the IEEE 33 buses. The effects of power imbalance, frequency resonance, and the quality factor. The anti-islanding methods used were: Harmonics Analysis, Vector Surge, Under/ Overfrequency and Voltage, Rate of Change Frequency, Rate of Change of Output Power, Rate of Change of Voltage, Active Drift Frequency, and Slip Mode Frequency Shift. With the results obtained in the simulations, it was possible to analyze that controls have the bus voltage as a reference for photovoltaic generation reduce non-detection zone. However, increase the occurrence of undue actions. For synchronous generation, the use of terminal voltage control increases non-detection zones.