Real-time implementation of three-level inverter-based D-STATCOM using neuro-fuzzy controller

Abstract

A distribution static compensator (D-STATCOM) is a custom power device connected in parallel to a power system to address electric power quality problems caused by reactive power and harmonics. To obtain high performance from a D-STATCOM, the D-STATCOM's dq-axis currents must be controlled in an internal control loop. However, control of the D-STATCOM's currents is difficult because of its nonlinear structure, cross-coupling effect between the dand q-axis, undefined dynamics, and fast changing load. Therefore, the controller to be preferred for a D-STATCOM should have a nonlinear and robust structure. In this study, a neuro-fuzzy controller (NFC), which is a robust and nonlinear controller, is proposed for dq-axis current control of a D-STATCOM. A DSP-based experimental setup is built for real-time control. The basic building block of the experimental setup is a three-level cascaded inverter. This inverter is constructed by using three IPM intelligent modules. A DS1103 controller card is used for real-time control of the D-STATCOM's experimental setup. The control algorithm is prepared in MATLAB/Simulink software and loaded to the DS1103 controller card. The performance of the NFC current-controlled D-STATCOM is tested for different load conditions: no load to full inductive, no load to full capacitive, full inductive to full capacitive, and full capacitive to full inductive. For this aim, the reactive current setpoint is changed as a step. The experimental results are presented to show the efficiency of the proposed controller under different load conditions.

Enhancing the performance of cascaded three-level VSC STATCOM by ANN controller with SVPWM integegration

“…Cascaded VSC topology is based on the series connection of H-bridges with separate dc voltage sources. In this VSC structure, the number of output voltage levels can be easily increased by adding or decreased by removing the H-bridges [6,17]. Nowadays, cascaded H-bridge VSC can be connected to distribution systems without using step-down transformers because of commercially available IGBTs with high voltage and current ratings.…”

“…With the advancement of microprocessor and semiconductor technology, cascaded multilevel VSC-based custom power devices have been introduced in distribution systems. STATCOM is a VSC-based custom power device and meets the load current compensation requirements such as reactive power compensation [4][5][6].…”

“…Furthermore, it provides fast dynamic response while maintaining the stability of the converter system over a wide operating range. Currently, various researchers have introduced in literature the improvement of STATCOM performance using ANN techniques [6,8,[13][14][15]. These studies are depending on sinusoidal-PWM (SPWM) technique for controlling switching gates of VSC, where SPWM is considered a conventional technology, which has been extensively used because it improves the voltage harmonic components to higher frequencies.…”

A New Controller for Voltage and Stability Improvement of Multi Machine Power System Tuned by Wind Turbine

“…Recently, to satisfy the necessity of the control system and escape the rising difficulty encountered by the conventional regulators scheme, Artificial Intelligence controllers have been widely developed [19]. A Neural Network observer of doubly fed induction generator (DFIGs) was established to increase the oscillatory stability of the power system including wind turbine [20].…”

Simulation and Design of Three-Level Cascaded Inverter Based on Soft Computing Method

“…Although many different multilevel inverter topologies have been proposed in literature, there are three well known topologies. These are; Cascaded H-Bridge ML Inverter [12], [17][18][19], Diode Clamped (Neutral Point Clamped NPC) ML Inverter [12], [20,21] and Flying-Capacitor (FC) ML Inverter [12], [22,23]. Each topology has its own advantages and disadvantages.…”