Electrical Power Quality Enhancement by Flexible SVC Controller

Abstract

Electrical distribution systems suffer from widespread loads, insufficient reactive power correction, and poor control. D-STATCOMs are connected in shunt with the distribution network to get the desired performance, but they are more expensive than static VAr compensators (SVC). Existing SVCs are affordable replacements for DSTACOMs. However, their TCR injects harmonics into source side currents due to erroneous firing angles for thyristors. The problem with existing SVCs was investigated in detail. After analyzing SVC switching strategies, the improved SVC at 3-phase, 50 Hz, 11 kV/400 volts, and the Dyn-11, 200 kVA distribution transformer was designed and implemented in MATLAB Simulink. The improved SVC has four thyristor-switched capacitor banks organized in binary sequence and a single-step thyristor-controlled reactor. The SVC controller was developed in MATLAB Simulink, utilizing fuzzy logic and artificial neural network approaches individually. Also, the investigation effort involved SVC switching at 3-phase, 50 Hz, 440 V/440 V, Dyn-11, and a 5 kVA prototype distribution transformer. Changes in system parameters like load voltages, frequency, and reactive power are inputs to these controllers; therefore, they must precisely set TBSC size and TCR firing angle. This improved SVC has shown significant and desired improvements in all system parameters by injecting minimum harmonics in source currents. newlineHence, after confirming desired results in simulation, the hardware system of improved SVC was implanted in a 5 kVA prototype distribution transformer by training the microcontroller like fuzzy and ANN controllers in Simulink. This improved SVC hardware has also delivered excellent results by injecting low harmonics in source currents. These results showed that these SVC controllers are feasible and scalable. newline