Control of DSTATCOM in 3-Phase 3-Wire Distribution System using Modified IcosØ Algorithm

In this paper, a 3-leg VSC (voltage source converter) based DSTATCOM (Distribution Static Compensator) is used for load compensation in 3-phase 3-wire distribution system. The control algorithm is based on IcosØ algorithm. This modified IcosØ algorithm is used for extracting the reference source currents for Power Factor Correction, Load Balancing and Voltage Regulation at PCC (point of common coupling). For various load conditions such as a reactive linear load, an unbalanced load and a non-linear load, Simulations are performed for Power Factor Correction (PFC) mode and Zero Voltage Regulation (ZVR) mode in MATLAB environment using SIMULINK and SimPowerSystem toolbox. Steady state and dynamic results on a developed hardware prototype of DSTATCOM are also presented to validate the control algorithm for DSTATCOM. Keywords-DSTATCOM, Control algorithm, Power quality, Nonlinear load, Load balancing, Harmonics compensation, Voltage regulation

Dynamic Weighted Round Robin Approach in Software-Defined Networks Using Pox Controller

Load balancing is important in solving over-load traffic problems in the network. Therefore, it has been among the first appealing applications in Software Defined Networking (SDN) networks. Numerous SDN-based load-balancing approaches have been recommended to enhance the performance of SDN networks. However, network control could be more manageable in large networks with hundreds of switches and routers. The SDN is a unique way of building, controlling, and developing networks to modify this unpleasant situation. The major concept of SDN contains logically centralizing network management in an SDN controller, which manages and observes the behaviour of the network. Numerous load-balancing approaches are known, such as Round Robin (RR), random policy, Weighted randomized policy (WRP), etc. Every load-balancing policy approach has some benefits and detriments. This paper developed an advanced load-balancing algorithm, a dynamic weighted round-robin (DWRR), and ran it on the top of the SDN controller. Then we calculate the result of our proposed load-balancing approach by comparing it with the current round-robin (RR) and weighted round-robin (WRR) approaches. Mininet tool is utilized for the investigation, and the controller utilized as the control plane is named the POX controller

Load balancing of communication channels with the use of routing protocols

In the article the authors propose a method for load-balancing of network resources forthe case which uses a routing protocols. In the first part of the article the authors present currentlyused algorithms for load balancing and possibilities of their modification. Through the introductionof additional hardware components for each node: the agent and the probe; it is possible to monitorand control the current system performance. The whole analyzed network is treated as a complexsystem. This allows to eliminate overloading of route nodes (through ongoing analysis of the optimaloperating point for a given node). Load balancing can be achieved using a modified mechanism ofECMP. The proposed approach allows for dynamic adjustment of load to network resources and thuseffectively to balance network traffic

Analysis of Scalable Algorithms for Dynamic Load Balancing and Mapping with Application to Photo-realistic Rendering

This thesis presents and analyzes scalable algorithms for dynamic load balancing and mapping in distributed computer systems. The algorithms are distributed and concurrent, have no central thread of control, and require no centralized communication. They are derived using spectral properties of graphs: graphs of physical network links among computers in the load balancing problem, and graphs of logical communication channels among processes in the mapping problem. A distinguishing characteristic of these algorithms is that they are scalable: the expected cost of execution does not increase with problem scale. This is proven in a scalability theorem which shows that, for several simple disturbance models, the rate of convergence to a solution is independent of scale. This property is extended through simulated examples and informal argument to general and random disturbances. A worst case disturbance is presented and shown to occur with vanishing probability as the problem scale increases. To verify these conclusions the load balancing algorithm is deployed in support of a photo-realistic rendering application on a parallel computer system based on Monte Carlo path tracing. The performance and scaling of this application, and of the dynamic load balancing algorithm, are measured on different numbers of computers. The results are consistent with the predictions of scalability, and the cost of load balancing is seen to be non-increasing for increasing numbers of computers. The quality of load balancing is evaluated and compared with the quality of solutions produced by competing approaches for up to 1,024 computers. This comparison shows that the algorithm presented here is as good as or better than the most popular competing approaches for this application. The thesis then presents the dynamic mapping algorithm, with simulations of a model problem, and suggests that the pair of algorithms presented here may be an ideal complement to more expensive algorithms such as the well-known recursive spectral bisection

Modelling load balance type static var compensator control system response

As power system interconnection becomes more prevalent, there has been an increase in use of thyristor controlled shunt connected compensation devices for dynamic power system compensation and power transmission capacity increase. A Static Var Compensator (SVC) functions as a variable reactance capable of operating in both the inductive and capacitive region as required on a cycle by cycle basis to provide compensation at the point of connection to the power system. Voltage regulation is the operational objective of most SVCs. Therefore, transient response of SVC control systems impacts overall power system performance and inappropriate settings may lead to voltage instability. SVCs are also commonly used to convert single phase load into balanced three phase load, thereby reducing negative phase sequence voltages and currents within the power transmission system. As most load balancing SVCs are consistently operated to their capacity, removal from service to apply and test control system setting changes impacts system regulation and stability. Therefore, model development of a load balancing type SVC control system to predict response to setting changes may provide an alternative to lengthy outages of SVC plant. This paper examines the theoretical basis of thyristor controlled shunt compensation, establishing conditions for voltage support and unbalanced load compensation. Load balancing type SVC control system model development and validation is documented

Load Balancing in SDN-Enabled WSNs Toward 6G IoE: Partial Cluster Migration Approach

The vision for the sixth-generation (6G) network involves the integration of communication and sensing capabilities in internet of everything (IoE), towards enabling broader interconnection in the devices of distributed wireless sensor networks (WSN). Moreover, the merging of SDN policies in 6G IoE-based WSNs i.e. SDN-enable WSN improves the network’s reliability and scalability via integration of sensing and communication (ISAC). It consists of multiple controllers to deploy the control services closer to the data plane for a speedy response through control messages. However, controller placement and load balancing are the major challenges in SDN-enabled WSNs due to the dynamic nature of data plane devices. To address the controller placement problem, an optimal number of controllers is identified using the articulation point method. Furthermore, a nature-inspired cheetah optimization algorithm is proposed for the efficient placement of controllers by considering the latency and synchronization overhead. Moreover, a load-sharing based control node migration (LS-CNM) method is proposed to address the challenges of controller load balancing dynamically. The LS-CNM identifies the overloaded controller and corresponding assistant controller with low utilization. Then, a suitable control node is chosen for partial migration in accordance with the load of the assistant controller. Subsequently, LS-CNM ensures dynamic load balancing by considering threshold loads, intelligent assistant controller selection, and real-time monitoring for effective partial load migration. The proposed LS-CNM scheme is executed on the open network operating system (ONOS) controller and the whole network is simulated in ns-3 simulator. The simulation results of the proposed LS-CNM outperform the state of the art in terms of frequency of controller overload, load variation of each controller, round trip time, and average delay