WAMS-based Hierarchical Active Power Differential Signal Algorithm for Backup Protection of a FACTS Compensated Transmission Network

This paper proposes a hierarchical active power differential signal-based generalized backup protection algorithm using Wide Area Mea- surement System (WAMS) data for Flexible AC Transmission System (FACTS)-compensated trans- mission networks. The proposed algorithm can be used for backup protection of transmission systems with any shunt and series-type FACTS devices. The increased number of FACT compensators affects the reliable operation of primary and backup protection of the transmission lines. Both shunt and series com- pensated lines cause malfunctioning of existing backup protection schemes. The proposed algorithm utilizes the sequence components of bus voltages and active power differential signals of lines to identify the faulty line. The algorithm is validated on a modified 9-bus system under MATLAB/SIMULINK platform. It is observed that the algorithm is suitable for identifying a faulty line in transmission systems containing both uncompensated and compensated lines with series or shunt-type FACTS controllers. This algorithm has the advantage that it uses a generalized backup protection logic and can be used for the accurate identification of a faulty line irrespective of the type of compensation devices

Variable fractional power‐least mean square based control algorithm with optimized PI gains for the operation of dynamic voltage restorer

Abstract The operation of Dynamic Voltage Restorer has been studied for the mitigation of supply voltage disturbances like sag, swell, distortions, and unbalances. A Dynamic Voltage Restorer with three single‐phase Voltage Source Converters has been implemented for this purpose. Dynamic Voltage Restorer's compensation capability has been evaluated while introducing the above‐said voltage related disturbances in the supply by different means. A control algorithm named Variable Fractional Power‐Least Mean Square has been proposed for generating the load reference voltage for Dynamic Voltage Restorer. Variable Fractional Power‐Least Mean Square extracts the fundamental active and reactive component out of non‐ideal supply voltage and is thus, used in generating reference load voltage. This algorithm is more robust with respect to disturbance due to variable step size and is computationally less expensive. In addition, an optimization‐based approach has been proposed to estimate the approximate values of PI control gains. For this reason, a population‐based optimization method known as Sine Cosine Optimization has been used. The added feature of the optimization method is the reduction of computational time as compared to conventional PI controller tuning. A model of Dynamic Voltage Restorer using Variable Fractional Power‐Least Mean Square control algorithm with Sine Cosine Optimization tuned PI gains has been built in MATLAB Simulink as well as a reduced scale experimental prototype and their results have been presented with discussion

Solar supplied two-output DC–DC converters in the application of low power

In this paper, solar fed single-input two-output Converter is discussed in the application of low power. The single-diode model is chosen for the solar panel modelling. The performance of this model is better in case of varying solar irradiation. It is operated with Maximum Power Point Tracking (MPPT) algorithm to achieve better efficiency. This paper also discusses the comparative study of two important MPPT algorithms such as Advanced Perturb and Observation (APO) and Incremental Conductance (IC) methods. The characteristics curves between power and voltage as well as between current and voltage are obtained from simulation work and these curves are compared with the actual characteristics curve. The solar-fed Zeta-Buck Boost and SEPIC-Cuk converters are analysed as a two output converter. Moreover, the converter has a DC bipolar output voltage with the ground connected power switch. The ground connected switch reduces the sparks on the switch. The system is simulated and modelled using MATLAB software and its performance is tested using real-time simulator using OP-5142

Performance of DSTATCOM using leaky LMS control algorithm

This paper describes a leaky least mean square-based control algorithm for a three-phase distribution static compensator (DSTATCOM) to mitigate multiple power quality problems such as reactive power, current harmonics, load unbalancing, and so on with self-supporting dc bus voltage of voltage source converter used as a DSTATCOM. The proposed control algorithm is implemented for the extraction of tuned weighted values of fundamental active and reactive power components of distorted load currents which are major components in reference supply currents. Developed DSTATCOM is operated under various operating conditions and its performance is found satisfactory

Adaptive theory-based improved linear sinusoidal tracer control algorithm for DSTATCOM

This paper presents a hardware implementation of three-phase distribution static compensator (DSTATCOM) using an adaptive theory-based improved linear sinusoidal tracer (ILST) control algorithm for different functions of DSTATCOM such as reactive power compensation for power factor correction, harmonics elimination, load balancing, and zero-voltage regulation under linear/nonlinear loads. An ILST-based control algorithm is used for the extraction of fundamental load currents and their active and reactive power components. These components are used for the estimation of reference source currents. A prototype of DSTATCOM is developed and its real-time performance is studied using a digital signal processor. The performance of DSTATCOM is found satisfactory with the proposed control algorithm under various types of loads

Neural network based conductance estimation control algorithm for shunt compensation

For mitigation of power quality problems in a distribution system, it is important to estimate effecting factors which are responsible for their origin. Main objectives of neural network application in Distribution Static Compensator (DSTATCOM) are to enhance the efficiency, robustness, tracking capability according to requirements. A control algorithm based on load conductance estimation using the neural network is implemented for DSTATCOM in a four wire distribution system. The proposed control algorithm is used for extraction of load fundamental conductance and susceptance components of distorted load currents. It is implementated for mitigation of power quality problems such as reactive power compensation, harmonics elimination, load balancing and reduction of neutral current under linear/nonlinear loads. Test results on a developed DSTATCOM have shown the acceptable level of performance under balanced and unbalanced loads

Admittance based control algorithm for DSTATCOM in three phase four wire system

This presents a hardware implementation of a distribution static compensator (DSTATCOM) in three-phase four wire distribution system using admittance based control algorithm. It is used for reactive power compensation, load balancing, harmonic elimination, neutral current compensation and voltage regulation under linear/nonlinear loads. Admittance based control algorithm is employed for estimation of load admittance where an active power of the load is used to estimate the conductance (GL) and reactive power of the load estimate the susceptance (BL). These components are used for estimation of reference active and reactive source currents respectively. A zig zag transformer is used for the neutral current compensation. A voltage source converter based DSTATCOM is developed as an active shunt compensator using a digital signal processor. The performance of developed DSTATCOM is found satisfactory with the proposed control algorithm for various types of loads

Composite observer-based control algorithm for distribution static compensator in four-wire supply system

This study presents an implementation of composite observer-based control algorithm in three-leg voltage source inverter (VSI)-based distribution static compensator (DSTATCOM) in four-wire power distribution network. This control algorithm is used for extraction of load fundamental current components of polluted load currents. These components of load currents are used for estimation of reference source currents to generate the gating pulses of insulated gate bipolar transistors used in VSI of DSTATCOM. This control algorithm is implemented for mitigation of power quality problems such as reactive power compensation, harmonic elimination and load balancing under linear/non-linear loads. The performance of DSTATCOM is found quite satisfactory for these unbalanced loads

Implementation of kernel incremental metalearning algorithm in distribution static compensator

This paper presents implementation of distribution static compensator (DSTATCOM) using kernel incremental metalearning algorithm (KIMEL) control algorithm. It demonstrates the functions of DSTATCOM such as reactive power compensation, harmonics elimination, and load balancing under linear and nonlinear loads with its self-supporting dc-bus voltage. The proposed control algorithm based on KIMEL is applied for extraction of fundamental active and reactive power components of load currents that are required for estimation of reference supply currents. These reference supply currents are used for gating pulses generation using indirect current control principle. A DSTATCOM with features of self-supporting dc bus (capacitor) is developed using DSP (dSPACE-1104), and the response of proposed control algorithm is studied under various operating conditions and found satisfactory