Fast multilayer perceptron neural network-based control algorithm for shunt compensator in distribution systems

In this study, a fast learning method of back-propagation (BP) multilayer perceptron neural network-based control algorithm for shunt compensator in three-phase distribution systems is presented. The proposed method comprises of quadratic linear and non-linear errors to determine optimisation criterion error function to train the BP algorithm while the existing methods have used only linear quadratic error term. The newly developed optimisation criterion error function accelerates the convergence efficiency of BP algorithm for performance improvement of shunt compensator at point of common coupling under non-linear loading conditions. With the help of the proposed algorithm, the weighted amplitude of fundamental active and reactive current components of the load current are extracted from which the reference source currents are estimated. The performance analysis of the proposed algorithm has been evaluated using two case studies for zero-voltage regulation and power factor correction. The total harmonic distortions are improved in comparison with standard BP algorithm which has been validated in above-mentioned two case studies. This is the quite important advantage of the proposed control algorithm to improve the power quality over existing control algorithms for shunt compensator

A discrete derivative control technique for DC link voltage in shunt compensator

This paper presents a discrete derivative control technique for dc-link voltage in shunt compensator. It is desired to maintain the dc-link voltage at reference level value for current compensation using Distribution Static Compensator (DSTATCOM) to improve the power quality of distribution systems. The proposed control strategy improves the dynamic performance of DC control loop by taking the values of the error of the reference and feedback quantity with its discrete derivative value. Multiplied these values with the proportional factors in such a way that they maintained these values at the same scale level. The errors with their absolute values are taken in account to keep the calculation amount close to that of PI (Proportional Integral) controller. The performance was studied by MATLAB software simulation using Power System toolbox, result shows reduction in the occurrence of transient occurred on DC-Link voltage at the initial stage, also it reaches the reference level so fast. The control technique has been implemented with the Anti-Hebbian control algorithm developed for the extraction of fundamental reference source currents required for power devices switching. The control technique has been verified for power factor correction to improve the power quality of a three phase distribution system using DSTATCOM. MATLAB Simulink platform is used to study the performance of the proposed control technique under dynamic conditions of nonlinear load