Distribution Static Synchronous Compensator Research Articles

Optimizing the hybrid PVDG and DSTATCOM integration in electrical distribution systems based on a modified homonuclear molecules optimization algorithm

AbstractThe increasing use of non‐linear loads in electrical distribution systems (EDS) led to a greater need for reactive power compensation, losses minimization, improved voltage and stability. This paper proposes the optimal integration of hybrid photovoltaic distributed generation (PVDG) and distribution static synchronous compensator (DSTATCOM) into IEEE 33 and 69‐bus EDS. A modified version of homonuclear molecules optimization (mHMO) is developed to determine the optimal allocation of the devices, while minimizing a multi‐objective function (MOF) based on total active power losses (TAPL), total voltage deviation (TVD), and investment cost of integrated devices (ICPVDGand ICDSTATCOM). The primary objective of the mHMO is to enhance the equilibrium between exploration and exploitation in the original HMO by implementing a fresh exploration stage. The effectiveness of mHMO was assessed using CEC17 benchmark functions. The findings demonstrate that mHMO achieved excellent results, including high‐quality solution and a favourable convergence rate. Additionally, results demonstrate that mHMO outperforms its basic version in reducing TAPL by 94.27% and 97.87% for the two EDS, while improving voltage profiles and reducing the cost of integrated devices. This study shows the potential of hybrid PVDG‐DSTATCOM in improving the performance of EDS and highlights the effectiveness of mHMO in optimizing their integration.

Simultaneous allocation of renewable energy sources and custom power quality devices in electrical distribution networks using artificial rabbits optimization

Abstract This study suggests an optimal renewable energy source (RES) allocation and distribution-static synchronous compensator (D-STATCOM) and passive power filters (PPFs) for an electrical distribution network (EDN) to improve its performance and power quality (PQ). First, the latest metaheuristic artificial rabbits optimization (ARO) is used to locate and size solar photovoltaic (PV), wind turbine (WT) and D-STATCOM units. In the second stage, ratings of single-tuned PPFs and D-STATCOMs at the RESs are determined, considering non-linear loads in the network. The multi-objective function reduces power loss, improves the voltage stability index (VSI) and limits total harmonic distortion. Simulations using the IEEE 33-bus EDN compared the ARO results with those of previous studies. In the first scenario, ideally integrated D-STATCOMs, PVs and WTs reduced losses by 34.79%, 64.74% and 94.15%, respectively. VSI increases from 0.6965 to 0.7749, 0.8804 and 0.967. The optimal WT integration of the first scenario outperformed the PVs and D-STATCOMs. The second step optimizes the WTs and PQ devices for non-linear loads. WTs and D-STATCOMs reduce the maximum total harmonic distortion of the voltage waveform by 5.21% with non-linear loads to 3.23%, while WTs and PPFs reduce it to 4.39%. These scenarios demonstrate how WTs and D-STATCOMs can improve network performance and PQ. The computational efficiency of ARO is compared to that of the pathfinder algorithm, future search algorithm, butterfly optimization algorithm and coyote optimization algorithm. ARO speeds up convergence and improves solution quality and comprehension.

POWER QUALITY AND RELIABILITY ENHANCEMENT BY DSTATCOM

Over the recent period of time, power quality problems have been marked as a buzzing issue with regards to promote delicate or miniature power electronic devices where Voltage sag problem is the most frequently occurring as well as detrimental power quality problems. Thus, the purpose of this study is to assuage voltage sag problem using proposed Distribution Static Synchronous Compensator (D-STATCOM). Utility distribution networks, sensitive industrial loads and critical commercial operations suffer from various types of outages and service interruptions which can cost significant financial losses. In developing countries such as India, where the power frequency and many such other determinants of power quality are themselves a serious question. The DSTATCOM is a most effective device which is based on the VSC principle. In this paper DSTATCOM, under different faults is analyzed. The modeling and simulation of the proposed shunt compensator was implemented in MATLAB Simulink environment. Simulation results showed that the proposed shunt compensator was efficient in mitigating voltage sags power system. Keywords: Power Quality, Distribution Static Synchronous Compensator (DSTATCOM), Voltage Source Converter (VSC), MATLAB.

A Distribution Static Synchronous Compensator Application to Mitigate Voltage Variation for Distribution Feeders

With the growing penetration of distributed energy resources (DER), the accompanying challenges have led utilities to limit the hosting capacities of DER installations on distribution feeders. A distribution static synchronous compensator (DSTATCOM) is a power electronic device to provide dynamic injections and absorption of reactive power into the distribution grid with more flexible and reliable voltage control and power quality improvement. A distributed energy resources management system (DERMS) is developed to provide more effective control of a DSTATCOM that can help substantially increase hosting capacity and mitigate overvoltage problems with the existing feeder. A Taiwan power company’s (Taipower) feeder is selected for computer simulation, and the DSTATCOM is employed in the test feeder to demonstrate the effectiveness of the DSTATCOM in improving the overvoltage problems. The voltage/reactive power (Volt/VAR) control of the DSTATCOM helps reduce overvoltage/voltage fluctuations as the DER output increases.

Improvement of Power Quality in Primary Distribution Systems Based on Static-Var Compensators

A flexible AC Transmission Systems (FACTS) is a new technology offers a fast and reliable control over the transmission and distribution parameters like voltage and phase angle between the sending end voltage and receiving end voltage. Distribution static synchronous compensator (DSTATCOM) is a second generation member of the (FACTS) controllers. Reactive power compensation is an important aspect in the control of distribution systems. Reactive current in addition to increasing the distribution system losses, introduces voltage drop at lead point and finally it causes poor power quality in power systems. Primary radial distribution feeders have high resistance to reactance ratio, which causes voltage drop and high power loss in radial distribution systems. providing high demanding power to entire load while maintaining voltage magnitude at acceptable range is one of the major system constraints, using of capacitor banks to improve the reactive power have not quite enough at high reactive power feeder, because it have more slow in step by step response and have not capable to generate continuously variable reactive power. In some primary distribution feeders at the state of Khartoum, it is observed that there are some appropriate drops in voltage and quality service at high reactive power loads although some individual capacitor banks have been connected at these feeders, from here we researched for a new technology to overcome this problem. A steady-state model of (DSTATCOM) is proposed and developed to compensate the reactive power by using a Voltage Source Converter (VSC) with Pulse Width Modulation (PWM) and cascade control of four direct proportional integral controllers (PI) in synchronous reference frame. The detailed modeling and control design of (DSTATCOM) with specific typical radial primary distribution feeders (industrial, commercial, residential) are presented and implemented along necessary mathematical model equations in the Matlab software. Simulation schemes of (DSTATCOM) are done with help of control block diagrams and stability analysis. Load flow is an important method for analysis, operation and planning studies of any power system in a steady-state condition. In this research backward forward sweeps load flow method (Kirchhoff’s Laws) has been proposed rather than Newton-Raphson and Fast decoupled methods because the distribution feeders have a high R/X ratio which make the systems are ill-conditioned iterations analysis. (DSTATCOM) was installed on specific typical radial feeders at the (DSTATCOM) which using for distribution lines and load compensation has been the subject of considerable interest beside it is a new technology for a good power quality solution. Keywords: Power System, Flexible AC Transmission Systems (FACTS) Devices, STATCOM, PI Controller DOI: 10.7176/ISDE/13-1-05 Publication date: May 31 st 2023

An intelligent mitigation of disturbances in electrical power system using distribution static synchronous compensator

The power quality of an electrical system is critical for industrial, commercial, and housing applications, and with the increasing use of sensitive loads, customers and utilities are beginning to pay more attention to it. A distribution static synchronous compensator (D-STATCOM) represents one of the best custom power devices (CPDs) for improving the power quality of a distribution system. The performance of this device relies upon the algorithm and strategy used for its control. Artificial intelligence was utilized to overcome these shortcomings, while a response optimizer tool was used for the tuning process. An adaptive controller design was also proposed, based on the integration of fuzzy logic with traditional proportional-integral (PI) controller. The fuzzy logic controller system was designed using the adaptive neuro fuzzy interference system (ANFIS) editor. In this work, a D-STATCOM controller was used to mitigate sag and swell problems, while the ANFIS together with the optimization method was used to improve the system response. This study was carried out using MATLAB/Simulink, and the results showed a superior and adaptive performance in mitigating voltage sag and swell problems at different loading conditions compared to the traditional PI.

Multi-objective control strategy for multilevel converter based battery D-STATCOM with power quality improvement

Differences in battery state-of-charge (SOC) in a cascaded H-bridge multilevel converter (CHB-MLC) based distribution static synchronous compensator (D-STATCOM) in battery storage system (BSS) applications could result in undesirable efficiency and performance reductions, and even system failure. Moreover, faults occurring on batteries and/or H-bridges (modules) of CHB-MLC severely increase the risk of failure. Power quality at the output of CHB-MLC is reduced as results of those faults. Therefore, active power differences that are introduced by SOC balancing among modules and bypassing the faulty modules yield to undesired harmonics at the output of CHB-MLC. This paper proposes a multi-objective control strategy for CHB-MLC based BSS D-STATCOM. The proposed control strategy includes a bidirectional power flow controller with unity power factor operation (UPF) feature, a fault-tolerant (FT) controller, a SOC balancing scheme that is designed to work on fault conditions, and a harmonic minimization strategy to enhance the power quality at the output of the CHB-MLC. Performance of the proposed method is validated through different operating conditions including faults, unbalanced SOCs and dynamic load changes. Results indicate that charging and discharging of the batteries with 5 kW rated power are held successfully along with maintaining UPF operation under both normal and fault conditions. Moreover, grid currents are balanced with the help of the FT controller and SOC balancing is properly operated even in fault conditions. Negative impacts of faults and unbalanced operating conditions on the power quality are also mitigated with the help of the harmonic reduction controller with significant decreases on total harmonic distortion reaching up to 47% and 69% during normal operation and faulty operations, respectively.

Optimal Placement and Sizing of D-STATCOMs in Electrical Distribution Networks Using a Stochastic Mixed-Integer Convex Model

This paper addresses the problem regarding the optimal placement and sizing of distribution static synchronous compensators (D-STATCOMs) in electrical distribution networks via a stochastic mixed-integer convex (SMIC) model in the complex domain. The proposed model employs a convexification technique based on the relaxation of hyperbolic constraints, transforming the nonlinear mixed-integer programming model into a convex one. The stochastic nature of renewable energy and demand is taken into account in multiple scenarios with three different levels of generation and demand. The proposed SMIC model adds the power transfer losses of the D-STATOMs in order to size them adequately. Two objectives are contemplated in the model with the aim of minimizing the annual installation and operating costs, which makes it multi-objective. Three simulation cases demonstrate the effectiveness of the stochastic convex model compared to three solvers in the General Algebraic Modeling System. The results show that the proposed model achieves a global optimum, reducing the annual operating costs by 29.25, 60.89, and 52.54% for the modified IEEE 33-, 69-, and 85-bus test systems, respectively.

English

Introducing a new concept for improving power quality in the distributed power generation sectors based on an inverter technology using Distribution STATCOM (DSTATCOM) power quality conditioner using the fuzzy logic controller. A five-level inverter is designed with Space Vector Modulation (SVM) and a fuzzy-based controller for the improvement of the power factor. It enhances the stability of the power system. Also, this concept describes various mitigation methodologies for improving power quality. Simulation results and laboratory-validated results are shown to compare the performances.

Strategic incorporation of DSTATCOM and distributed generations in balanced and unbalanced radial power distribution networks considering time varying loads

The article focuses on the optimal planning of distribution static synchronous compensator (DSTATCOM) and distributed generation (DG) to minimize power losses, and simultaneously enhance the voltage profile, and voltage stability at various nodes of the Radial Power Distribution Networks (RPDN). The study involves combinational choices in the use of the DSTATCOM and DG and it relies on heuristic algorithms namely the Enhanced artificial bee colony algorithm (EABC) which has been formulated based on a modification in the searching strategy of the traditional artificial bee colony algorithm (ABC) by integrating the particle swarm optimization (PSO). The proposed optimization model considers the multiobjective function, including the power loss reduction, branch current capacity limit violation, and node voltage deviation. In the proposed approach, the optimal rating of DG and DSTATCOM is estimated under various load steps by using the EABC algorithm. Two different test cases namely base case, and combined installation of DG and DSTATCOM units were considered to analyze the distribution network performance at different load factors. The power loss minimization, voltage profile, and voltage stability improvement of the network before and after the allocation of DG unit and DSTATCOM is depicted. The study examines the effectiveness of the proposed method through a simulation run on 33-node balanced and IEEE 13-node unbalanced RPDN under time varying load demand. Simulation results reveal that the combined installation of DG unit along with DSTATCOM at a suitable location in 33-node and 13-node distribution networks can minimize the power loss by 62% and 43% respectively under the time varying load demand considered along with significant improvement in voltage profile and voltage stability of the network.

A Review on D-STATCOM for Power Quality Enhancement

Power quality problems in electric systems are one of the important topics that occupy a wide area of ​​interest to researchers and engineers. The increased use of power electronics circuits has led to improve efficiency and performance of the equipment; on the other hand, they withdraw a non-sinusoidal current and increase the harmonics which causes a decrease in the power quality. Also, these electronic devices are sensitive to power quality problems. However, advanced electronics can be employed to mitigate these problems. The Distribution static synchronous compensator (D-STATCOM) is one of the Custom Power Devices (CPDs) used for this purpose. D-STATCOM can be designed with different topologies, algorithms, and techniques of control to mitigate various power quality problems that face the power system. Selecting the D-STATCOM design depends on the power quality problem that needs to be mitigated. This paper presents a literature review of D-STATCOM from its beginnings to the present day.

Dynamic Voltage Equalization Control of D-STATCOM Under Unbalanced Grid Faults in a Low-Voltage Network

Unbalanced grid faults are very harmful to the network operation. Distributed static synchronous compensator (D-STATCOM) can help to support the grid voltage by injecting the reactive power into the inductive power grid. However, this approach turns to be ineffective for a low-voltage grid, where the network impedance is mainly resistive. In this article, a dynamic voltage equalization control (DVEC) scheme is proposed to suppress the negative sequence voltage, and therefore, reduce the voltage unbalance during the faults in the resistive network. This effect is achieved through transferring proper active power from the negative sequence channel to the positive sequence channel. And the dual-sequence active currents are controlled by DVEC without exchanging extra active power with the grid except the little circuit loss compensation. By flexibly adjusting the control parameter of DVEC, current peak and active power oscillation can be limited within a preset range, respectively, during the process of maximizing the voltage control. As a result, the DVEC scheme can ensure the safe operation of D-STATCOM and the stability of the power grid. Moreover, experimental results are reported to validate the correctness and effectiveness of the proposed scheme.

Power quality improvement using Distribution Static Synchronous Compensator

A Power quality problem is an occurrence manifested as a nonstandard voltage, current or frequency that results in a failure or a mis-operation of end user equipments. Hence, the optimal advancement of power quality is concentrated by this proposed model with Deep Belief Nets (DBN) and Convolutional Neural Networks (CNN) utilizing Distribution Static Synchronous Compensator (DSTATCOM). Here, the major objective is that for the mitigation of current distortion, voltage enhancement, along with minimization of harmonics, the reactive power control in DSTATCOM is focused more by utilizing DBN with CNN. Utilizing the proposed Simulink design model of DSTATCOM, which is employed for enhancing the power quality in a distributed system, the aforementioned objective could be obtained. The simulations were performed using MATLAB SIMULINK. From the simulation result it is observed that the proposed framework have successfully accomplished harmonic substance and voltage profile enhancement.

A Novel Hybrid Optimization Controlled DSTATCOM Model for Power Quality Enhancement

Power quality issues, high voltage drop, and power loss possess a greater impact on the efficiency of electrical systems. Incorporating compensators within the distribution network can significantly reduce these problems. The proposed technique involves installing a Distribution Static Synchronous Compensator (DSTATCOM) in the distribution system, which can compensate for reactive power and eliminates harmonics. Moreover, the paper suggests a technique for obtaining an optimal dc-link voltage depending upon the grid’s need for load compensation under balanced and unbalanced loads. An innovative Squirrel Sooty Tern Optimization Algorithm (SqSTOA) is used to regulate the switching signals of the voltage source converter, which improves the power quality. Using Matlab/Simulink, the suggested system’s performance is examined, and the findings demonstrate SqSTOA's proficiency in enhancing power quality. Additionally, it delivers high dc-link output, reduced settling time, and enhances the steady-state response. By contrasting the optimized DSTATCOM controller with standard optimization techniques like WdCH, FFA, SSA, and STOA as well as without optimization, its applicability is determined.The suggested system’s outputs with the proposed algorithm have higher levels of accuracy when compared to those of traditional algorithms, like FFA, SSA, and STOA.

Modeling and Simulation of DVR and D-STATCOM in Presence of Wind Energy System

The present study suggests that series voltage injection is more effective than parallel current injection to improve voltage quality on the load side. The line voltage can be accurately symmetrized at the connection point by creating and controlling a series voltage component in each phase. This is more reliable and effective than parallel current injection. A dynamic voltage restorer (DVR) and a distribution static synchronous compensator (DSTATCOM) were utilized to provide the required power. The DVR is an effective and modern device utilized in parallel within the grid and can protect sensitive loads from voltage problems in the grid by injecting voltage. The DVR and D-STATCOM were used to improve voltage stability in faults. A standard 13-bus system was studied in the presence of a wind farm. The simulation results demonstrated that single and three-phase overloads dramatically altered the voltage of the system, making it necessary to use compensators to improve voltage stability. The DVR and D-STATCOM showed similar performance under normal conditions and somewhat improved grid voltage unbalance. However, the DVR outperformed D-STATCOM under asymmetric faults conditions and led to lower voltage variations.

Digital Control of DSTATCOM using TI-C2000 Processor and MATLAB/ Simulink for Sustainable Power System Network

This paper describes the detailed digital control of a Distribution Static Synchronous shunt Compensator (DSTATCOM) using a MATLAB embedded coder for compensation to be in command of Voltage Source Converter (VSC) input voltage, reactive power compensation and the power factor improvement of a secondary radial distribution system with a voltage rating of 11kV/415V and with a capacity of 750 kW. The model has been simulated and tested in MATLAB/Simulink using the Simscape tool block set version of MATLAB R2019a. The same is achieved using a 32-bit DSP TMS320F2812 controller programmed with CCS V 6.1 software and tested with MATLAB embedded coder generation using Texas Instrument C2000 processors. Using this embedded code is developed and dumped into the CCS V 6.1. Real and Reactive power control (PQ) and Back Propagation Control Algorithm (BPCA) are the control methods. BPCA controller is based on the elementary extracted biased value of Reactive Power (Q) and Active Power (P) components of load currents. These current values are necessary for the reference source's current estimation. The reference source currents are estimated from the available source currents to generate firing pulses for the PQ and BPCA controllers. The real and reactive power controller is based on the transformation of synchronously rotating load currents in alpha and beta frames. The BPCA-based DSTATCOM is simulated for linear and non-linear load circumstances and that helps in restoring the power system networks sustainability.

Impact of D-STATCOM and OLTC with Integrated Volt/var Control in Distribution System for Power Loss Minimization and Voltage Control

ABSTRACT Voltage control and power loss minimization are some of the crucial issues in distribution system energy management. Finding the best strategy for Voltage control and power loss reduction is a critical task for the distribution network operator (DNO). The main contributions of the proposed work are (i) determination of size and location of the Distribution Static Synchronous Compensator (DSTATCOM) with (OLTC). (ii) to minimize the power loss and Voltage deviation with the Volt/var control strategy. (iii) To obtain the impact of single and multiple D-STATCOM units with and without OLTC. The proposed method is tested on two test systems: (i) IEEE-69 RDS and (ii) IEEE-25 bus three-phase unbalanced system. The benefits of the proposed results are addressed in the reduction of power loss, enhancement of the Voltage profile, and the annual cost of saving for the DNO. The results are tabulated, verified, and compared with other methods. The power loss is reduced to 39.25%, 38.04% for 69 bus and 25 bus test systems. The minimum Voltage profile is enhanced from 0.90918 pu to 0.9619 pu for 69 bus RDS and from 0.922559 pu to 0.9747 pu for 25 bus three-phase system.

A Comprehensive Modeling for Wind Turbine Generator and DSTATCOM into Backward/Forward Load Flow Algorithm

Backward/forward load flow algorithm is commonly used in the power system, particularly in radial distribution networks. However, the rapid development in the power electronics technologies makes power systems more flexible with the integration of Renewable Energy Resources (RESs) and compensation devices. Consequently, this paper presents simple models for wind turbine generators based on Squirrel Cage Induction Generator (SCIG) and Distribution Static Synchronous Compensator (DSTATCOM) into a backward/forward load flow algorithm. In the wind generator model, the mechanical powers are collected from the manufactures data where the electrical power is calculated through the SCIG equivalent circuit and injected as negative loads at the connected buses. The second model in this paper is the DSTATCOM devices which are utilized to recover the SCIG reactive power. In the proposed model, the connected DSTATCOM bus is converted to a voltage-controlled bus (PV-bus type) with zero active power. Moreover, the reactive power of the DSTATCOM is updated during the iterative process until the load flow convergence. The simplified models for both wind generators and DSTATCOM are validated based on standard IEEE 33-bus and 85-bus radial distribution systems. The obtained results show the feasibility and effectiveness of the proposed models.

Coordinated Volt/Var Control of PV and EV Interfaced Active Distribution Networks Based on Dual-Stage Model Predictive Control

This article presents a dual-stage coordinated control approach for voltage regulation and congestion management of active distribution networks (ADN) in the presence of photovoltaic (PV) generators and electric vehicle stations (EVS). The proposed scheme operates on rule-based model predictive control (RBMPC) to optimally manage the settings of the regulating devices, i.e., on-load tap changer (OLTC), distribution static synchronous compensator (DSTATCOM), PV generators, and EV inverters that possess different temporal characteristics. The first (hourly time-scale) and the second (one-minute time-scale) stages of the dual-stage coordinated control mechanism are designed to correct the long-term and short-term voltage fluctuations, respectively. The objectives of the proposed approach are to minimize the number of OLTC operations (first stage) and changes in set-points of PV and EV inverters, and DSTATCOM (second stage) in addition to minimization of slack variables, energy loss, and voltage error at EV stations. In both the stages, predefined rules are set for MPC to optimize different objectives on the basis of the magnitudes of bus voltages. Simulations are performed on 33-bus and 38-bus distribution networks to test the efficacy of the control approach. It is observed that the proposed approach could mitigate the voltage variations as well as line congestion for different scenarios.

Minimization of the distribution operating costs with D-STATCOMS: A mixed-integer conic model

This paper addresses the problem of determining the optimal location and operation of distribution static synchronous compensators (D-STATCOMs) in power distribution networks. Metaheuristic algorithms have been conventionally used to solve this mixed-integer nonlinear programming problem. In contrast, we propose a mixed-integer second-order cone programming (MI-SOCP) model that guarantees global optimum and fast convergence of the algorithms in optimization solvers. The model seeks to minimize the annual installation cost and the operating cost, subject to active and reactive power balance constraints, voltage regulation bounds, devices capabilities, and the number of D-STATCOMs available to be connected. The multiobjective nature of the problem is also analyzed and solved using the proposed MI-SOCP model. An extensive set of simulations on the IEEE-33 nodes test system demonstrate the advantages of this approach compared to conventional heuristic algorithms and with solutions given by algebraic modeling software.